Обзор американских кардиологических журналов за неделю (ссылки)

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Researchers report distinct initial atrial activation patterns in noncoronary aortic sinus-atrial tachycardia
Liu X. J Am Coll Cardiol. 2010;56:796-804.

An almost simultaneous activation of the biatrial paraseptal region and diffuse area of initial activation in each of the atria are included as the distinctive initial activation patterns of noncoronary aortic sinus-atrial tachycardia, researchers have documented in a new study.

The group of researchers from China, France and the United Kingdom utilized 3-D electroanatomic mapping during noncoronary aortic sinus-atrial tachycardia (NCAS-AT) in 13 patients and during pacing sequentially from the noncoronary aortic sinus (NCAS) and the para-Hisian atrial area in 15 reference patients. Researchers also used CT in 25 additional reference patients — and gross and microscopic anatomic examination in 12 human hearts — to analyze the spatial relationship between the NCAS and the contiguous atria.

According to study results, the para-Hisian area of the right atrium and the anteroseptal region of the left atrium were activated almost simultaneously during NCAS-AT. Researchers also reported that the initial activation area was relatively wide (9.3 ± 2.6 cm² on the right atrium map; 8.1 ± 2.1 cm² on the left atrium map).

Additionally, NCAS pacing in reference patients reproduced a biatrial activation pattern of NCAS-AT and resulted in a wider initial activation area than para-Hisian atrial pacing within first 20 ms of right atrium activation.

“These activation patterns have implications in improved diagnosis of NCAS-AT, thereby minimizing the risk of inadvertent ablation in the para-Hisian region,” the researchers commented in the concluding statement of their study. “Moreover, in the absence of myocardial tissue in the NCAS, peri-NCAS-AT may be an appropriate terminology.”
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Intra-atrial reentrant tachycardia found lower than previous studies

Stephenson EA. J Am Coll Cardiol. 2010;56:890-896.

Rates of intra-atrial reentrant tachycardia were lower in a recent cross-sectional, multicenter study than previous studies had reported, which researchers attribute in part to changes in surgical strategy.

The Pediatric Heart Network Fontan Cross-Sectional study was composed of 520 children from seven centers who were aged 6 to 18 years. Each of the children had undergone a Fontan procedure at least 6 months before entering the study. Study data within 3 months of enrollment featured echocardiograms, electrocardiograms, exercise testing results, health status questionnaires and medical history from a review of the medical record.

Supraventricular tachycardias were reported in 9.4% of patients, whereas intra-atrial reentrant tachycardia (IART) was present in 7.3% of the population. Four to 6 years after Fontan, the hazard of IART decreased, but it increased after this time period.

Researchers identified the following independent associations of time to occurrence of IART: lower Child Health Questionnaire physical summary score (P<.001); predominant rhythm (P=.002; highest risk with paced rhythm); and type of Fontan operation (P=.037; highest risk with atriopulmonary connection).

“This contemporary cohort of Fontan survivors represents one of the largest datasets available in this unique population,” the researchers wrote. “Overall prevalence of IART (7.3%) is lower in the current cohort than in previous reports. Independent associated factors of IART development include a paced rhythm, lower functional status, and an atriopulmonary connection Fontan, a previously suspected risk factor for atrial tachycardia.”

In an accompanying editorial, George F. Van Hare, MD, from Washington University/St. Louis Children’s Hospital, St. Louis, commented on the Fontan procedure and its role in clinical practice.

“It is disappointing, but perhaps not altogether surprising, that one observes some atrial arrhythmias in patients with the external conduit Fontan,” he said. “The Fontan is not a legacy operation like the Senning procedure for transposition, and with improved survival for the Norwood/Sano operation, more and more children will be coming to surgery for Fontan completion, and so the management of these arrhythmias will continue to occupy us.”

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Change in Serum Lipids After Acute Coronary Syndromes: Secondary Analysis of SPACE ROCKET Study Data and a Comparative Literature Review
Michael C. Kontos, M.D., F.A.C.C.
October 07, 2010

Barth JH, Jackson BM, Farrin AJ, et al. Change in serum lipids after acute coronary syndromes: secondary analysis of SPACE ROCKET study data and a comparative literature review. Clin Chem 2010;56:1592-8.

Lipid values are commonly thought to decrease rapidly after the onset of MI. However, most studies were performed 20-30 years ago. Using data from the SPACE ROCKET Trial, the authors re-examined this relationship. The SPACE ROCKET trial was an open-label, national, multicenter, randomized, controlled trial comparing the efficacy and tolerability of 40 mg simvastatin versus 10 mg rosuvastatin in patients admitted with an acute coronary event within the preceding two weeks, requiring secondary prevention with a statin.1 Patients were not excluded if they were already taking a statin at time of admission unless it was 80 mg simvastatin or 80 mg atorvastatin per day. Participants were included in this secondary analysis if the participating hospital laboratory used the same analysis methods on the routine day one samples as the central laboratory, as significant bias has been reported between analysis methods.2

Routine hospital admission (day one) blood samples (fasting or nonfasting) were used for analysis, as well as a follow up sample obtained on days two –four. Total cholesterol, HDL cholesterol, and triglycerides were measured, and LDL cholesterol was calculated using the Friedewald equation.

A secondary objective of this report entailed a comprehensive analysis of published studies examining the effect of AMI on lipid concentrations in which the absolute concentration of cholesterol and triglycerides was given at specific time points and no lipid-modifying treatment was given during the study period. The mean changes for total cholesterol and triglycerides were calculated, weighted according to the number of participants in each study.

Of the 1263 participants enrolled into the SPACE ROCKET trial, 128 met the entry criteria for this sub-study. Total cholesterol changed from 205 to 178 mg/dL (absolute difference 27 mg/dL, relative change 8.6%) and LDL from 134 to 117 mg/dL (absolute difference 17 mg/dL, relative change 13%). In contrast, no significant difference was observed in HDL or triglyceride concentrations between day one and days two – four.

A secondary analysis reviewed 26 papers including 2122 participants in studies from 1963 – 2008. These studies reviewed total cholesterol and triglyceride concentrations at identified days post AMI. The median study size was 39 patients (range 12–565). The combined results demonstrated that total cholesterol fell by about 10% in the 14 days after ACS.

The authors concluded that the SPACE ROCKET trial data, along with a comparison of previously published data found that there was a 10% fall in total cholesterol after AMI—a difference that they concluded was of high clinical significance.

Commentary

It has been widely accepted that serum cholesterol (and by association, LDL) falls in the first few days after AMI. Sampling time immediately after AMI is required to obtain an accurate profile. As the authors note, this view was based on studies that were in general very small, ranging in size from 12 to 123 participants, with the average only 39 per trial. When the combined results were reviewed, the results were consistent with the current study, with an approximate 10% reduction in total cholesterol. Although the authors comment that this is a highly significant result, these changes are actually fairly minor and unlikely to change overall treatment plans.

In contrast, the largest study performed thus far by Pitt et.al4 enrolled 507 patients, of which approximately 40% had STEMI, 30%, had non-STEMI, and 30% had unstable angina. The initial sample was taken a median of 26 hours after symptom onset. There was a slight change in lipid values over the next 84 hours, which was not different based on presenting ACS type. Changes in values, although statistically significant, were not clinically significant.

Why the difference in results? First, an important limitation of this study is that the number of patients included is relatively small. Second, the decrease in cholesterol after acute MI is hypothesized to result from the effects of severe stress. It is possible that improvements in care and changes in the diagnostic criteria for MI patients result in only small amounts of myocardial damage, which in turn causes less stress. This may explain the finding that almost all studies reported since 20024-8 have demonstrated only small changes in cholesterol (typically <10% relative change) in contrast to studies performed in the 1960s and 1970s. Unfortunately, this study, as well as many others, failed to report the size and type of MI, making it difficult to determine the effects of MI size.

Another potential but unlikely explanation is that lipid values decrease very acutely, within the first few minutes to hours after MI onset. As most studies have some delay in obtaining the lipid profile, this acute decrease would be missed. Using a calculated LDL could also play a role; if the patient was non-fasting, triglycerides would be increased, artificially lowering the LDL value.

What are the implications of this study? Although it appears that both total cholesterol and LDL do decrease, the change does not appear clinically significant, and therefore unlikely to make a substantial clinical change in overall treatment, given current recommendations to treat all MI patients with a statin. For those who believe that lower is better and that maximal statin therapy is indicated no matter the LDL, then treatment will not change. However, for those who believe in targeting a specific LDL goal, knowing the initial LDL level could allow better targeting of statin dose. This has become more important given the substantial cost differential between generic, low-cost, less potent statins, and more potent but non-generic statins.

The results of this study, in conjunction with their review of prior ones, dispels the myth that lipids obtained after the first 24 hours are not valid. Lipid values, even if obtained two-three days later after admission (with the caveat that it may not apply to patients with very large MIs or those in cardiogenic shock) will be relatively equivalent to the patient’s baseline values.

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One-year lifestyle intervention beneficial for severely obese adults
Goodpaster BH. JAMA. 2010;doi:10.1001/jama.2010.1505.
Ryan DH. JAMA. 2010;doi:10.1001/jama.2010.1531.

Severely obese adults who adhered to an intensive lifestyle intervention using behavior-based diet and physical activity for 1 year experienced significant improvements in weight loss and cardiometabolic risk factors, according to researchers at the University of Pittsburgh School of Medicine.

Bret H. Goodpaster, PhD, and colleagues presented 1-year data on the effects of intensive lifestyle intervention in severely obese adults at the 28th Annual Scientific Meeting of the Obesity Society. The results were simultaneously published in the Journal of the American Medical Association.

The study included 130 adults aged 30 to 55 years with severe obesity who were recruited by local advertisements and mass mailings. The participants were randomly assigned to two groups for a 1-year: diet and physical activity regimen for 1 whole year or diet with a physical activity regimen that began after 6 months. All participants attended group sessions and received individual and telephone contacts.

Both groups lost a significant amount of weight in the first 6 months, but the initial physical activity group lost significantly more weight than the delayed activity group: 10.9 kg vs. 8.2 kg. At 12 months, however, there was no significant difference in the weight loss between the groups: 12.1 kg in the initial physical activity group and 9.9 kg in the delayed activity group.

At 6 months, the initial physical activity group had significantly greater reductions in body fat and waist circumference compared to the delayed activity group, but at 12 months, there was no significant difference in loss between the groups. The initial activity group lost significantly more hepatic fat content. The researchers also noted improvements in blood pressure, serum liver enzyme levels, fasting insulin and insulin resistance in both groups.

“Our data make a strong case that serious consideration should be given by health care systems to incorporating more intensive lifestyle interventions similar to those used in our study,” the researchers concluded. “Additional studies are clearly needed to determine long-term efficacy and cost-effectiveness of such approaches.”

In an accompanying editorial, Donna H. Ryan, MD, of Pennington Biomedical Research Center, Louisiana State University System, and Robert Kushner, MD, MS, of Northwestern University Feinberg School of Medicine, said studies such as this one “are needed to unravel the causes, identify prevention strategies and develop the best treatments for obesity.

“Optimal treatment approaches for class 2 and class 3 obesity are underexplored, while payment approaches for interventions known to work have yet to be adopted,” the editorialists wrote.
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Dyssynchrony indices not predictive of response to CRT
Miyazaki C. Circ Heart Fail. 2010;3:565-573.

New data from Circulation: Heart Failure suggest that dyssynchrony indices should not be used to guide use of cardiac resynchronization therapy in patients with HF.

“Multiple small retrospective studies suggested that various echocardiographic dyssynchrony indices have high sensitivity and specificity for identifying patients with a favorable response to cardiac resynchronization therapy (CRT),” the researchers commented in their study. “However, the multicenter prospective Predictors of Response to CRT (PROSPECT) trial was not able to identify any echocardiographic dyssynchrony parameter that added significant incremental value to the current simple QRS duration and clinical selection criteria for CRT.”

To help further clarify the role of dyssynchrony indices in CRT, the researchers performed a comprehensive, prospective, single-center trial enrolling 184 patients with HF with anticipated CRT from September 2005 to September 2007.

The final study population (n=131) had wide QRS and left ventricular ejection fraction <35%. All patients underwent clinical evaluation, echocardiography, Minnesota Living with Heart Failure Questionnaire, 6-minute walk distance and cardiopulmonary exercise testing for measurement of peak oxygen consumption before implantation and 6 months after implantation. Researchers analyzed 14 dyssynchrony indices by timing intervals (98%), tissue velocity (96%), M-mode (94%), tissue Doppler strain (92%), 2-D speckle strain (65%-86%) and 3-D echocardiography (79%).

At the 6-month follow-up, researchers reported reverse remodeling (end-systolic volume reduction >15%) in 55% of patients and more frequently in those without vs. with ischemic cardiomyopathy (71% vs. 42%; P=.002). Dyssynchrony index did not predict reverse remodeling in nonischemic cardiomyopathy, whereas indices derived using ischemic cardiomyopathy M-mode (area under curve [AUC], 0.67), tissue Doppler strain (AUC, 0.79), and isovolumic time (AUC, 0.76) were predictive of reverse remodeling (P<.05 for all).

Additionally, no indices assessed by Minnesota Living with Heart Failure Questionnaire, 6-minute walk distance or peak oxygen consumption were predictive of clinical response.

Limitations of note included lack of paired data for clinical response variables in some patients, the possibility of differences in data analysis between this and other studies, as well as the possibility that adjustment for LV lead position relative to dyssynchrony and scar may have improved the predictive value of mechanical dyssynchrony for reverse remodeling.

“The current findings, in concert with those of the PROSPECT and Cardiac Resynchronization in Heart Failure studies, indicate that the decision to use CRT should be based on standard guidelines and do not support a routine clinical use of any echocardiographic dyssynchrony indices to select patients for CRT,” the researchers wrote. “Although superior measures of mechanical dyssynchrony may be developed, the consistent findings observed with the large number of parameters assessed in this study do not engender optimism that use of CRT can be further refined by measurement of mechanical dyssynchrony in patients with advanced symptoms, low ejection fraction and conduction delay.”

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CARDIoGRAM study to expand knowledge on the role of genetic variation in CAD
Preuss M. Circ Cardiovasc Genet. 2010;doi:10.1161/CIRCGENETICS.109.899443.

A documented increase in risk for MI of more than 25% in three single nucleotide polymorphisms is leading researchers to conduct CARDIoGRAM, the largest published individual coronary artery disease genome-wide association study, according to a recent proof-of-principal analysis published online by Circulation: Cardiovascular Genetics.

The Coronary Artery Disease Genome-Wide Replication and Meta-Analysis (CARDIoGRAM) study is a genome-wide association meta-analysis of individuals with European ancestry, involving more than 22,000 cases with CAD and/or MI and 60,000 controls. All genotyping was performed on Affymetrix or Illumina platforms followed by imputation of genotypes in most studies.

According to data presented in their analysis, there was a strong association between CAD and the single nucleotide polymorphisms rs1333049 (OR=1.29; 95% CI, 1.22-1.36), rs2383206 (OR=1.28; 95% CI, 1.22-1.35), rs10757278 (OR=1.28; 95% CI, 1.21-1.35), but no association with rs10811661 (OR=1.02; 95% CI, 0.98-1.05).

Collectively, the consortium will enhance the statistical power to association by increasing the sample size by a factor of 10 for cases and 20 for controls, the researchers commented in their analysis.

“These larger samples are likely to substantially enhance the detection of true associations for CAD risk. Furthermore, we have prepared for a substantial replication phase and defined hierarchical levels of evidence a priori to help attach an appropriate level of confidence to our various findings as they emerge,” they added.
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Distinct characteristics of myocytes reported in patients with type 1 long-QT syndrome
Moretti A. N Engl J Med. 2010;363:1397-1409.

Myocytes of patients with type 1 long-QT syndrome exhibit prolongation of the action potential, altered IKs activation and deactivation properties, and an abnormal response to catecholamine stimulation with a protective effect of beta-blockade, study data have shown.

“Even though the incidence of the long-QT syndrome is only one case per 2,500 live births, [type 1 long-QT syndrome] provides a platform for showing the suitability of induced pluripotent stem-cell technology as a means of exploring disease mechanisms in human genetic cardiac disorders,” researchers wrote.

In the study, researchers screened a family affected by type 1 long-QT syndrome, which included an 8-year-old boy and his 42-year-old father, 39-year-old aunt and 70-year-old grandfather. They identified an autosomal dominant missense mutation (R190Q) in the KCNQ1 gene and collected dermal fibroblasts from two family members and two healthy controls. The fibroblasts were then infected with retroviral vectors encoding the human transcription factors OCT3/4, SOX2, KLF4 and c-MYC to generate pluripotent stem cells.

According to researchers, induced pluripotent stem cells maintained the disease genotype of long-QT syndrome type 1 and generated functional myocytes. Expression of cell type-specific markers and recordings of the action potentials in single cells indicated a “ventricular,” “atrial” or “nodal” phenotype of individual cells.

Additional characterization of the role of the R190Q-KCNQ1 mutation in the syndrome’s pathogenesis suggested a dominant negative trafficking defect, which was associated with a 70% to 80% reduction in IKs current and altered channel activation and deactivation properties. Furthermore, myocytes derived from patients with long-QT syndrome type 1 had a heightened susceptibility to catecholamine-induced tachyarrhythmia, which was attenuated by beta-blockade.

“Larger sets of long-QT syndrome cell lines harboring different channel mutations will be needed to further validate the disease phenotype and compare pathogenetic mechanisms in diverse forms of the disease,” the researchers concluded. “Clinically, the severity of manifestations of the long-QT syndrome varies among family members, and incomplete penetrance exists. However, we did not observe any phenotypic differences in the prolongation of the action potential between the myocytes from our two patients, a finding that is probably due to the similarity of the clinical phenotype in these cases.”

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No association between KIF6 Trp719Arg polymorphism and CAD risk

Assimes T. J Am Coll Cardiol. 2010; doi:10.1016/j.jacc.2010.06.022.

Topol E. J Am Coll Cardiol. 2010; doi:10.1016/j.jacc.2010.06.023.

Patients with nonfatal coronary artery disease who had KIF6 Trp719Arg polymorphism genotyped did not have an increased risk for developing clinical coronary artery disease, according to recent findings published in the Journal of American College of Cardiology.

Researchers included participants with nonfatal CAD (cases, n=17,000; controls, n=39,369) of European descent, as well as a modest number from other regions, from 19 international case-control studies. The KIF6 Trp719Arg polymorphism (rs20455), which was found in earlier studies to be associated with CAD development, was genotyped either as part of a genome-wide association study or in a formal attempt to replicate the initial positive reports.

According to study results, carriers of the 719Arg allele vs. noncarriers did not have an increased risk for CAD in any of the 19 studies. The researchers ruled out with high degree of confidence an increase of at least 2% in the risk for CAD among European 719Arg carriers with regression analyses and fixed-effects meta-analyses. Additionally, among a subset of European 719Arg carriers with early onset disease (men, <50 years old; women, <60 years old), there was no reported increased risk for CAD vs. either similarly aged controls or non-European subgroups.

“Our findings question not only the usefulness of the KIF6 test in identifying subjects at increased risk of incident or recurrent CAD but also its usefulness in identifying subjects most likely to benefit from statins,” the researchers wrote. “Although we could not test the latter hypothesis directly, the previously reported interaction between genotype and benefit from statins is largely dependent on the validity of the association among subjects not taking statins, which could not be replicated in this study.”

Eric J. Topol, MD, and Samir B. Damani, MD, PharmD, both of the Scripps Translational Science Institute and the Scripps Research Institute, La Jolla, Calif., in accompanying editorial, said there is meta-analysis for strongly refuting the KIF6 link to CAD.

“Such genetic and pharmacogenetic markers must be accompanied by stringent vetting by investigators in well-designed, hypothesis-free, genome-wide studies before promoting their use in clinical practice,” they concluded. “Going forward, the KIF6 story should serve as a valuable reminder of the potential pitfalls present in prematurely adopting a genomic test without sufficient evidence

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Stress test performed in more than half of patients within 2 years of revascularization
Shah B. J Am Coll Cardiol. 2010;56:1328-1334.

Nearly 60% of all patients in community practice who underwent revascularization had at least one cardiac stress test within 24 months of the procedure, new study data suggested.

“Although the routine use of stress testing within 2 years of revascularization is considered inappropriate by recent American College of Cardiology Foundation appropriate use criteria (ACCF AUC), […] more than 50% of patients of a large national insurance provider had at least one stress test between 90 days and 2 years after coronary revascularization in community practice,” the researchers wrote.

Their study included patients between the ages of 18 and 64 years who underwent revascularization. All patients were taken from UnitedHealthcare’s claims database from July 1, 2004 to June 30, 2007.

Of the total study population (n=28,177), percutaneous coronary intervention was performed in 21,046 cases and CABG in 7,131 cases. Fifty-nine percent had at least one cardiac stress test within 24 months, with 61% in the PCI arm and 51% in the CABG arm.

According to researchers, the incidence of testing was found to increase at both 6 months and 12 months after revascularization, suggesting an association with elective follow-up office visits. There was also notable stress test incidence variability in geographic locations with at least 300 revascularizations, ranging from 52% (Columbus, Ohio) to 71% (Phoenix).

“Our findings provide a perspective on the real-world patterns of stress testing after revascularization and, more importantly, on the geographic variability and yield of post-revascularization stress imaging in community practice,” the researchers concluded. “Further studies are warranted to investigate specific drivers for stress testing and the possible role of ACCF AUC in guiding clinical decision-making.” – by Brian Ellis

This article examines data collected before and soon after appropriate use criteria (AUC) for single-photon emission CT myocardial perfusion imaging were published, indicating that imaging routinely soon after revascularization in asymptomatic patients is inappropriate. This analysis does not include, therefore, data exclusive to the period of decline in procedure growth in nuclear cardiology (ie, 2006 and beyond). Much of this imaging was driven by local community practice standards and fear of liability in this high-risk population. The AUC actually freed up physicians to follow stricter guidelines. Now that SPECT AUC have been promulgated, it would be important to reassess this data to determine if the restriction of stress testing has improved outcomes or caused some patients with ischemia post-revascularization to be undertreated.

Also, it should be noted that the 5% rate of revascularization is somewhat misleading in terms of the value of the noninvasive tests. Many symptomatic patients were very likely spared invasive evaluation, saving vascular risks, contrast material, time off of work and health care dollars by having a negative or low-risk stress nuclear myocardial perfusion scan.
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CMR detected key characteristics after right ventricular ischemic injury
Masci P. Circulation. 2010;122:1405-1412.

Early postinfarction right ventricular injury was common in patients with acute STEMI and characterized by the presence of myocardial edema, late gadolinium enhancement and functional abnormalities, researchers reported in Circulation.

“Experimental data show that the [right ventricle] is more resistant to ischemia than the left ventricle,” the researchers commented in their study. “We have demonstrated that [right ventricular] edema and late gadolinium enhancement, reflecting ischemic myocardial injury, are often present early after reperfusion of STEMI.”

The study included 242 consecutive patients from three European centers between May 2006 and September 2008. Patients had reperfused acute STEMI and were excluded if they had prior MI or revascularization, atrial fibrillation, cardiogenic shock, renal failure, contraindications to CV magnetic resonance (CMR) and any known clinical condition that may affect right ventricular function.

At 1 week and 4 months after MI, patients were studied with CMR. Researchers performed T2-weighted scans to depict myocardial edema and post-contrast CMR to determine late gadolinium enhancement.

Study results showed that after infarction, right ventricular edema was found in more than half the patients (51%) and was regularly associated with late gadolinium enhancement (31% of patients). In anterior LV infarcts, right ventricular edema was found in 33% and late gadolinium enhancement in 12% of the cases. Researchers also recorded an inverse relationship between baseline regional and global right ventricular functions and the presence and extent of right ventricular edema and right ventricular late gadolinium enhancement.

Additionally, at follow-up, researchers observed a decrease in frequency (10.3%) and extent of right ventricular late gadolinium enhancement (P<.001). Multivariable analysis revealed the presence of right ventricular edema as an independent predictor of right ventricular global function improvement during follow-up (beta coefficient=0.221; P=.003).

The researchers said the key findings of their research were: temporary right ventricular dysfunction is frequently present early after infarction and is determined primarily by right ventricular ischemic involvement; although the right ventricle is preferentially involved in inferior LV infarcts, it is not uncommon to find similar, albeit less extensive, abnormalities in anterior LV infarcts as well; a significant reduction in frequency and size of right ventricular late gadolinium enhancement is observed at follow-up; and persistent right ventricular late gadolinium enhancement occurs in a minority of patients, most likely representing postinfarction myocardial fibrosis, and is associated with adverse right ventricular remodeling and worse function at follow-up.

“These findings support previous clinical and animal studies showing that the [right ventricle] is more resistant to ischemia than the LV and that acute postinfarction [right ventricular] dysfunction is likely an expression of viable rather than irreversibly damaged myocardium,” the researchers said. “Moreover, it is important to realize that in patients with anterior LV infarction, ischemia may extend toward the adjacent [right ventricular] free wall and lead to transient [right ventricular] dysfunction.”

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Follow-up SPECT myocardial perfusion imaging scans performed infrequently in patients without prior CAD
Carryer D. Circ Cardiovasc Imaging. 2010;3:520-526.

Routine follow-up of single-photon emission CT myocardial perfusion imaging was performed infrequently in patients without prior coronary artery disease, whereas the rate was twofold higher in patients with previous coronary artery disease, study data suggested.

The study included patients from the Mayo Clinic in Rochester, Minn., who had normal stress SPECT scans in 2002. Patients were excluded if they did not grant research authorization in accordance with Minnesota state law, had any fixed defect greater than what was considered mild and had any reversible defect.

Of the 2,354 patients identified as having no prior CAD, 449 (19%) had follow-up scans, with 309 (13%) having routine follow-up scans. The median time for follow-up was 2.1 years, with only 64 patients (21%) having a follow-up scan after the time to 1% risk for death or MI (ie, warranty period; median, 5.5 years).

In patients with prior CAD (n=656), 39% (n=259) had follow-up scans, with 26% (n=171) having routine scans. The median time for follow-up was 1.6 years, which, conversely to the patients without CAD, was longer than the warranty period (0.9 years).

Regarding the opportunity for improvement that was revealed by this data, the researchers said many of the cardiologists and non-cardiologists ordering SPECT myocardial perfusion imaging may be unaware or unfamiliar with appropriateness criteria or the concept of a warranty period after a normal stress SPECT myocardial perfusion imaging study. “Better physician education may result in more effective use of nuclear imaging resources, improved patient care and decreased costs,” they wrote. “Incorporating the science of a warranty period into appropriateness criteria ratings may strengthen their effectiveness.”
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Incidental findings in routine CT scans can predict CVD
Gondrie M. Radiology. 10.1148/radiol. 10100054.

Subclinical ancillary aortic findings on chest CT scans can be strong predictors of CVD risk, new study data suggest.

“The results of this study show that radiologists can predict CVD fairly well using incidental findings of calcifications of the aortic wall on CT, along with minimal patient information, such as age, gender and the reason for the CT,” said Martijn J. A. Gondrie, MD, of University Medical Center Utretch, The Netherlands, in a press release. “Ultimately, this easily executed extra risk stratification has the potential to reduce future heart attacks or other CV events.”

Researchers for the Prognostic Value of Ancillary Information in Diagnostic Imaging (PROVDI) study examined 817 patients who underwent CT scans for non-CV indications and 347 patients who experienced a CV event during the 17-month follow-up period. Patients were graded for incidental aortal findings, including calcifications, plaques, elongations and irregularities.

Each aortic abnormality was predictive of CV events (c index range, 0.70–0.72; goodness of-fit P value range, 0.45–0.76). A predictive model incorporating the sum score for each type of abnormality was most predictive (c index, 0.72; goodness of-fit P=.47) and was ultimately selected by the researchers as their model of choice.

The researchers validated the sum total model using an external data set and reported good performance (c index, 0.71; goodness-of-fit P=.25; sensitivity, 46%; specificity, 76%).

The study is the first “of its scale and scope that seeks to investigate the potential of incidental findings to predict future disease and thus identify patients at risk,” Gondrie said. “It generates the much-needed insights that allow more effective utilization of the increasing amount of diagnostic information, and it could potentially change the way radiologists contribute to the efficiency of daily patient care.”

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Radiofrequency Catheter Ablation of Atrial Fibrillation: A Cause of Silent Thromboembolism? Magnetic Resonance Imaging Assessment of Cerebral Thromboembolism in Patients Undergoing Ablation of Atrial Fibrillation
Gaita F, Caponi D, Pianelli M, et al.
Circulation 2010;122:1667-1673.
Study Question: What is the risk of cerebral thromboembolism (CTE) during radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF)?

Patterns of Cardiac Stress Testing After Revascularization in Community Practice
Shah BR, Cowper PA, O’Brien SM, et al.
J Am Coll Cardiol 2010;56:1328-1334.
Study Question: What is the incidence of cardiac stress testing (CST) following coronary revascularization with either percutaneous coronary intervention (PCI) or coronary artery bypass surgery (CABG)?

Benefit of Atrial Septal Defect Closure in Adults: Impact of Age
Humenberger M, Rosenhek R, Gabriel, et al.
Eur Heart J 2010;Oct 12:[Epub ahead of print].
Study Question: What is the effect of age on the clinical benefit of atrial septal defect (ASD) closure in adults?

Effect of Home Testing of International Normalized Ratio on Clinical Events
Matchar DB, Jacobson A, Dolor R, et al., on behalf of the THINRS Executive Committee and Site Investigators.
N Engl J Med 2010;363:1608-1620.
Study Question: What is the efficacy of self-testing of international normalized ratio (INR) in reducing the risk of a major event (stroke, major bleeding episode, or death)?

Midregional Pro-Atrial Natriuretic Peptide and Outcome in Patients With Acute Ischemic Stroke
Katan M, Fluri F, Schuetz P, et al.
J Am Coll Cardiol 2010;56:1045-1053.
Study Question: What is the prognostic value of midregional pro-atrial natriuretic peptide (MR-proANP) in patients with acute ischemic stroke?

Biomarkers in Acute Aortic Dissection and Other Aortic Syndromes
Ranasinghe AM, Bonser RS.
J Am Coll Cardiol 2010;56:1535-1541.
Perspective: The following are 10 points to remember about biomarkers in acute aortic dissection (AAD) and other aortic syndromes.

Testosterone Therapy in Women With Chronic Heart Failure: A Pilot Double-Blind, Randomized, Placebo-Controlled Study
Iellamo F, Volterrani MV, Caminiti G, et al.
J Am Coll Cardiol 2010;56:1310-1316.
Study Question: Does testosterone supplementation impact functional capacity and insulin resistance in women with advanced chronic heart failure?

Thrombosis of Second-Generation Drug-Eluting Stents in Real Practice: Results From the Multicenter Spanish Registry ESTROFA-2 (Estudio Espa?ol Sobre Trombosis de Stents Farmacoactivos de Segunda Generacion-2)
de la Torre Hern?ndez JM, Alfonso F, Gimeno F, et al, on behalf of the ESTROFA-2 Study Group.
JACC Cardiovasc Interv 2010;3:911-919.
Study Question: What is the incidence of second-generation drug-eluting stent (DES) thrombosis in clinical practice?

Chronic Kidney Injury in Patients After Cardiac Catheterisation or Percutaneous Coronary Intervention: A Comparison of Radial and Femoral Approaches (From the British Columbia Cardiac and Renal Registries)
Vuurmans T, Byrne J, Fretz E, et al.
Heart 2010;96:1538-1542.
Study Question: What is the incidence of chronic kidney disease (CKD) onset and its association with arterial access in patients after cardiac catheterization or percutaneous coronary intervention (PCI)?

Association of Combinations of Lipid Parameters With Carotid Intima-Media Thickness and Coronary Artery Calcium in the MESA (Multi-Ethnic Study of Atherosclerosis)
Paramsothy P, Knopp RH, Bertoni AG, et al.
J Am Coll Cardiol 2010;56:1034-1041.
Study Question: What is the association of combinations of lipid parameters with subclinical atherosclerosis?

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Title: Biomarkers in Acute Aortic Dissection and Other Aortic Syndromes
Date Posted: October 25, 2010
Authors: Ranasinghe AM, Bonser RS.
Citation: J Am Coll Cardiol 2010;56:1535-1541.

Perspective:
The following are 10 points to remember about biomarkers in acute aortic dissection (AAD) and other aortic syndromes:

1. Acute dissection of the ascending aorta (Stanford type A) is a surgical emergency. Mortality without surgical repair is approximately 1-2% per hour after onset of symptoms, with most patients succumbing within 30 days. Short-term survival increases to 70% with surgery.

2. A major obstacle to successful management of type A dissection is delayed diagnosis, often due to nonclassical presentations. The time between presentation and definitive management is >12 hours in the majority of patients and >24 hours in one-half of the patients in some studies.

3. Unlike the case with acute coronary syndromes where troponin levels and electrocardiograms facilitate risk stratification and emergency treatment, there are no rapidly available diagnostic tools for identifying AAD. Biomarkers for AAD are needed that are fast, easy to use, widely available, and temporally related to the event, with high sensitivity and specificity.

4. Products of aortic medial injury derived from smooth muscle cells (smooth muscle myosin, calponin), and the elastic laminae (soluble elastin fragments) have been studied as potential biomarkers in AAD.

5. A rapid (30-minute) assay for smooth muscle myosin heavy chain (smMHC) was studied in patients with AAD, myocardial infarction (MI), and control healthy volunteers. Using a cutoff level of 2.5 ng/ml, sensitivity was 90% in the first 3 hours, but was reduced to 72% in the next 3 hours, and to 30% subsequently. Specificity was 83% at this cutoff level at the 3-hour time point. Overall, this marker could be useful if measured early after presentation, but is not particularly useful at later time points.

6. Calponin, a troponin counterpart in smooth muscle, has three isoforms (acidic, basic, neutral) that have been studied in the setting of AAD. The acidic form was increased >2x and basic form >3x in all type A AAD within 6 hours of presentation, with acidic form continuing to rise up to 24 hours. No elevation was noted in non-AAD patients. During the first 6 hours, positive and negative predictive values were 56% and 84% for acidic calponin, whereas values for basic calponin were 44% and 86%, respectively.

7. An enzyme-linked immunosorbent assay measuring soluble elastin fragments (sELAF) was shown to have positive and negative predictive values of 94% and 98%, respectively, for AAD using a cutoff level of 3 standard deviations above a healthy population mean. Levels remain elevated >72 hours after presentation with AAD. However, in patients with a thrombosed lumen, the assay was negative, limiting its utility.

8. C-reactive protein levels, an acute phase protein produced primarily by the liver, have been shown to be elevated in patients with AAD and levels correlate with duration of symptoms; however, specificity for AAD is poor.

9. D-dimer is a fibrin degradation product present in the setting of fibrinolysis. Since thrombosis and subsequent fibrinolysis occurs in the setting of AAD, levels of D-dimer have been investigated as potential biomarkers. Levels are higher in the setting of AAD compared to MI, but are similar to those observed in pulmonary embolism. The IRAD-Bio group reported a sensitivity and specificity of 96% and 46% for AAD, respectively, when a cutoff value of 0.5 µg/ml was used within 24 hours of symptom onset.

10. Studies to prospectively test the clinical utility of these and other candidate biomarkers are needed. It may be that a panel of biomarkers will be most useful in the triage of patients toward timely definitive imaging for the diagnosis of AAD.

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Testosterone Therapy in Women With Chronic Heart Failure: A Pilot Double-Blind, Randomized, Placebo-Controlled Study
Iellamo F, Volterrani MV, Caminiti G, et al.
J Am Coll Cardiol 2010;56:1310-1316.
Study Question: Does testosterone supplementation impact functional capacity and insulin resistance in women with advanced chronic heart failure?

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Pneumococcal disease: A red flag in heart disease management
Inflammation via infection cited for causing a coagulation cascade that can lead to MI.

Pneumococcal disease, the leading cause of serious illness in children and adults worldwide, is leaving an irreparable mark on the lives of hundreds of thousands of Americans, as well as millions outside the US every year. Streptococcus pneumoniae, the common bacteria that initiates the disease, is the leading cause for bacterial pneumonia and can also lead to other conditions such as middle ear infection, meningitis and bacteremia.

For such widespread and, in some cases, deadly conditions, just a single dose of the pneumococcal polysaccharide vaccine has been proven to protect against the 23 types of S. pneumoniae bacteria responsible for causing more than 90% of all invasive pneumococcal disease cases in adults.

However, modern medicine is uncovering that vaccination may do more than prevent these infectious diseases, as pneumococcal disease may lead to CHD, the leading cause of death worldwide.

In a 2000 study, Daniel M. Musher, MD, and colleagues brought a possible link between pneumococcal disease and CHD to the medical community’s attention.

“The Centers for Disease Control and Prevention has been specifically targeting people with chronic conditions because we know that in the general population there is significant morbidity and mortality every year due to pneumococcal disease and people with chronic illnesses, like chronic heart disease, are at increased risk of complications caused by pneumococcal disease,” said Susan Rehm, MD, National Foundation for Infectious Diseases (NFID) medical director and vice chair of the department of infectious disease at Cleveland Clinic.

By the end of 20th century, there was little known about the association between pneumococcal pneumonia and CHD because it had received relatively little examination in medical literature. Despite this, the connection between infection and atherosclerosis had already been suggested by researchers for many years, according to Joseph Alpert, MD, department of medicine, University of Arizona, Tucson, and a Cardiology Today Editorial Board member.

“People have long been suggesting infection as an inciting factor in starting atherosclerosis,” Alpert said in an interview. “In fact, atherosclerosis probably starts with some inflammatory process, which could be a virus, an infection or an auto-immune condition. Then you have certain conditions that play into that inflammation, such as high cholesterol, hypertension, diabetes and genetic factors.”

The relationship between pneumococcal disease — one of the inflammation-inciting conditions — and CHD only began to receive attention in 2000 when Daniel M. Musher, MD, and colleagues published a study in Medicine. What had started as reporting on a series of patients with pneumococcal pneumonia turned into some of the first clues linking the two diseases. They found that five of the 100 admitted patients had acute myocardial events that they suspected were triggered by the physical stress of the pneumonia, whereas four patients had acute MI and one had acute onset of atrial fibrillation without documented ischemia.

These findings led Musher and fellow researchers to conduct what many cardiologists cite as the study that firmly established the connection between pneumococcal disease and CHD. This study, published 7 years after his initial findings, reported that of the 130 patients admitted during a 5-year period with pneumococcal pneumonia, 33 (19.4%) had at least one major cardiac event. Specifically, 12 had MI, of whom two also had arrhythmia and five had new-onset or worsening chronic HF; eight had new-onset AF or ventricular tachycardia, with six of these patients also having new chronic HF; and 13 had newly diagnosed or worsening chronic HF.

“It seemed quite clear that severe inflammation of one place in the body was associated with increased inflammation in the coronary arteries, which led to acute MI,” Musher said.

For William Schaffner, MD, president, NFID, and chair, department of preventive medicine at Vanderbilt University, the findings from this study were particularly important in substantiating the connection between the two diseases. “I may be the last infectious disease doctor that has gotten on this train, simply because I hadn’t read all these studies and integrated them in my mind,” he said. “The findings presented in the 2007 study are part of the evidence that goes to validate this concept. It stands to reason, given that this is correct, that if we could prevent pneumococcal disease, we could prevent a stress and insult on the CV system.” Conflicting data, unflinching resolve

In May, Tseng and colleagues published a study in JAMA that on first glance seemed to take the momentum out of the growing body of evidence confirming the link between pneumococcal disease and CHD. Among a cohort of men aged 45 to 69 years, the researchers concluded, receipt of pneumococcal vaccine was not associated with subsequent reduced risk for acute MI and stroke after accounting for baseline differences in participants who received vaccination vs. those who did not.

“This study essentially turned the coin over,” Schaffner told Cardiology Today. “The logic of the study goes not only will the vaccine protect against pneumonia, which could cause stress, but I wonder if the vaccine itself will have a demonstrable role in reducing the occurrence of some pretty hard endpoints — MI and stroke. That’s a big question to ask of the vaccine, which is only supposed to prevent pneumonia. The researchers could not demonstrate an affect [on these diseases] and frankly I’m not surprised. But it doesn’t negate in any way the importance of getting vaccinated to prevent the infectious illness.”

However, on second look, the study is more positive regarding the effect of pneumococcal vaccination than it may appear on initial read, Rehm said. “This large study said that vaccination with pneumococcal vaccine was not associated with MI or stroke. There have been concerns among physicians that giving a vaccination would provoke an inflammatory response that might result in stroke or heart attack,” she said. “This study showed that the vaccine does not stimulate stroke or heart attack.”

Alpert agreed that “the bottom line of this study is that it is perfectly safe to give the pneumococcal vaccination, even if the patient has heart disease,” he said. “In fact, it’s a good idea for patients to get vaccinated because if they develop pneumococcal pneumonia on top of their heart or lung disease, they often have a much more complicated course. Therefore, we’d like to protect them against having a severe bout of pneumococcal pneumonia.”

Even though most cardiologists may not have their practice set up for administering a vaccine, their role in whether their patients are vaccinated should still not be underestimated, Rehm said.

“Because cardiologists see patients at risk, not only with chronic heart disease, but also with peripheral vascular disease, chronic pulmonary diseases and so on, they are excellently situated to identify people who might benefit from pneumococcal vaccination,” she said. “Having the ability to administer vaccines in one’s practice setting varies from place to place, but the education a cardiologist can provide to a patient is extremely important.”

“The cardiologist’s recommendation is especially important because of all the motivators to get people to accept vaccines, the specific doctor’s recommendation directly to the patient is the most compelling and produces the most results,” Schaffner said. “This would stimulate a terrific amount of vaccination.”

To help spot those most in need of a vaccination, the NFID has published a number of specific criteria that physicians should keep in mind when dealing with their patients. They include:
Those 65 years of age and older.
Adults aged 19 to 64 years who have asthma or smoke cigarettes.
Everyone 2 years of age and older with chronic medical conditions such as diabetes; heart, kidney, liver or chronic lung diseases; or alcoholism.
Those whose immune systems have been weakened by such conditions as cancer or HIV infection.
People without a functioning spleen, and those with sickle cell disease.
Residents of chronic care or long-term care facilities.
Children at 2, 4 and 6 months of age, followed by a booster dose at 12 to 15 months.
Children aged 24 to 59 months who are at high risk for pneumococcal infection.

For Alpert, a cardiologist who recommends that all of his patients get vaccinated, pneumococcal vaccination is a necessity similar to vaccinations for the flu. “It is part of a standard primary care series of vaccinations,” he said. “Whatever the preventive measures are, people should definitely take them because, particularly as people get older and if they have heart or lung disease, these infections can be literally life-threatening.”

“It’s clear that pneumococcal disease is a regular hazard, particularly in people who have underlying heart disease. Vaccination against this disease is cheap, effective and a great preventive measure,” Schaffner said. “You can do an awful lot of good for your patients by making a simple and strong recommendation to be vaccinated.” – by Brian Ellis

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Barbershop-based BP monitoring improved hypertension control rate
Victor R. Arch Intern Med. 2010;doi:10.1001/archinternmed.2010.390.

Hypertensive male barbershop patrons whose barbers offered BP screenings and physician referrals at the time of their haircut exhibited better hypertension control rates than male patrons who received only pamphlets, a study found.

Such health outreach programs are becoming common in barbershops across the country, according to the study. They may ultimately reach more blacks than church-based programs, which only certain sections of the population attend regularly. “Black-owned barbershops hold special appeal for community-based intervention trials because they are a cultural institution that draws a large and loyal male clientele and provides an open forum for discussion of numerous topics, including health, with influential peers,” the researchers wrote.

Ronald G. Victor, MD, and colleagues identified 17 black-owned barbershops with 95% black male clientele in Dallas County, Texas. All black male customers were offered baseline BP screenings during a 10-week period. The researchers then randomly assigned the barbershops into an intervention group, in which barbers were trained to continually offer BP screenings and promote physician follow-up with peer-based messaging, or a comparison group, in which patrons received a standard BP pamphlet.

“The intervention’s theoretical underpinning was adapted from the successful AIDS Community Demonstration Projects that mobilized community peers to deliver intervention messages with role model stories and made medical equipment available in the daily environment,” the researchers wrote.

Interventions were performed in nine shops with 75 hypertensive men per shop. The comparison group consisted of eight shops with 77 hypertensive patrons per shop. At the end of 10 months, the hypertension control rate increased in the intervention group vs. the comparison group (absolute group difference, 8.8%; 95% CI, 0.8-16.9). The intervention’s effect on hypertension control was not affected by adjusting for several covariates, including age, baseline BP, college education, marital status or smoking status, and participation at both baseline and follow-up (P=.03). The researchers observed a borderline effect of intervention on systolic BP change (absolute group difference, –2.5 mm Hg; 95% CI, –5.3 to 0.3).

“If the intervention could be implemented in the approximately 18,000 black-owned barbershops in the United States to reduce systolic BP by 2.5 mm Hg in the approximately 50% of hypertensive US black men who patronize these barbershops, we project that about 800 fewer MIs, 550 fewer strokes, and 900 fewer deaths would occur in the first year alone, saving about $98 million in CHD care and $13 million in stroke care,” the researchers wrote.

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Bystander chest compression-only CPR linked with survival benefit for cardiac arrest

Bobrow B. JAMA. 2010;304:1447-1454.
Cone D. JAMA. 2010;304:1493-1495.

The application of chest compression-only CPR by a layperson bystander was associated with increased survival in patients experiencing out-of-hospital cardiac arrest, results from a new analysis suggested.

Researchers observed 5,272 patients with out-of-hospital cardiac arrests during the 5-year follow-up period of the prospective, observational study. All patients were at least 18 years of age and had out-of-hospital cardiac arrests between 2005 and 2009. The relationship between layperson bystander administering CPR and survival to discharge was characterized using multivariable logistic regression analysis. The primary outcome was survival to hospital discharge, which was determined by a review of hospital records.

According to the results, 4,415 out-of-hospital cardiac arrests were reported and 779 were excluded from the analysis because the CPR was administered by a health care professional or were evaluated in a medical facility; this included 666 people who received conventional CPR, 849 who received compression-only CPR and 2,900 who received no bystander CPR.

Rates of survival to hospital discharge were higher in the compression-only group (13.3%; 95% CI, 11.0-15.6) when compared with the group with no bystander intervention (5.2%; 95% CI, 4.4-6.0) and the conventional CPR group (7.8%; 95% CI, 5.8-9.8). The researchers also reported an increase in layperson CPR from 2005 to 2009 (28.2% to 39.9%, P<.001), along with an increase in the proportion of compression-only CPR during the same time period (19.6% to 75.9%, P<.001). In increase in overall survival was also reported from 2005 to 2009 (3.7% to 9.8%, P<.001).

“Implementation of a 5-year, multifaceted, statewide public education campaign that officially endorsed and encouraged chest compression-only CPR was associated with a significant increase in the rate of bystander CPR for adults who experienced out-of-hospital cardiac arrest,” the researchers concluded. “Furthermore, chest compression-only CPR was independently associated with an increased rate of survival compared with no bystander CPR or conventional CPR.”

In an accompanying editorial, David C. Cone, MD, of Yale University School of Medicine in New Haven, Conn., said the findings regarding compression-only CPR were in line with those of previous trials that had suggested a theoretical advantage but did not offer much confirmatory data, adding that the results were encouraging, and no associations with neurologically impaired survival were reported.

“Taken together, these findings, along with the findings of the compression-only CPR trials and the findings reported by Bobrow et al suggesting a survival benefit, should encourage and justify continuing investigations involving compression-only CPR,” Cone wrote.

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Insulin resistance linked with increased risk for stroke in patients without diabetes

Hankey T. Arch Neurol. 2010;67:1177-1178.
Rundek T. Arch Neurol. 2010;67:1195-1200.

Insulin resistance estimated using the homeostasis model assessment was a marker for an increased risk for incident stroke in those without diabetes, according to new study data.

Researchers of this prospective, population-based cohort study analyzed nondiabetic participants (n=1,509) from the Northern Manhattan Study (mean age, 68 ± 11 years; 62.4% women; 58.9% Hispanics). All members from this multi-ethnic urban community were free of stroke at baseline and were followed annually by telephone to determine any change in vital status, detect neurologic and cardiac symptoms and events, and review interval hospitalizations, risk factor status, medications and changes in functional status.

According to study data, the mean homeostasis model assessment (HOMA) of insulin sensitivity was 2.3 ± 2.1. During a mean follow-up of 8.5 years, one or more symptomatic vascular events were reported in 180 participants, 46 of whom had fatal or nonfatal ischemic stroke, 45 had fatal or nonfatal MI and 121 died from vascular causes. HOMA insulin resistance index in the top quartile (Q4) predicted the risk for ischemic stroke (adjusted HR=2.83; 95% CI, 1.34-5.99) when compared with less than Q4; however, this did not hold true with other vascular events.

This study, the researchers wrote, “provides evidence that insulin resistance as measured using HOMA is independently associated with an increased risk of first ischemic stroke. Insulin resistance may be a novel therapeutic target for stroke prevention. … In addition to secondary stroke prevention, future studies are needed to determine whether the treatment of insulin resistance can reduce the risk of incident stroke and CVD.”

In an accompanying editorial, Graeme J. Hankey, MD, with the School of Medicine and Pharmacology, University of Western Australia in Perth, and Tan Ze Feng, MD, from the First Affiliated Hospital of Jinan University, Guangzhou, China, said measuring insulin resistance may help refine prognostic estimates of future risk for stroke obtained by means of traditional risk stratification schemes.

“Although it is premature to widely screen for insulin resistance as a means to prevent stroke, its measurement may have a role in particular cases in which traditional risk stratification schemes suggest that the patient is at intermediate risk of stroke (rather than high or low risk) and in whom an additional finding of insulin resistance may be sufficiently compelling to supplement lifestyle advice with pharmacological interventions to lower stroke risk,” Hankey and Feng said.

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Occupational, leisure-time physical activity reduced risk for HF
Wang Y. J Am Coll Cardiol. 2010;56:1140-1148.

New data from a study featuring more than 55,000 Finnish men and women suggested that moderate and high levels of occupational or leisure-time physical activity may reduce the risk for HF.

The study cohorts included 28,334 men and 29,874 women from Finland, who were free of HF at baseline and between the ages of 25 and 74 years. Researchers utilized baseline measurement of different types of physical activity to predict incident HF and followed patients for a mean of 18.4 years.

During follow-up, HF developed in 1,868 (6.6%) men and 1,640 (5.5%) women. After adjusting for multivariates, including age, smoking, BMI and systolic BP, the HRs for HF were as follows for the three occupational activity levels in men: light, 1.00; moderate, 0.90; and active 0.83 (P=.005 for trend). For women, the HRs for the occupational activity levels were 1.00 for light, 0.80 for moderate and 0.92 for active (P=.007).

Similarly, HRs for HF during leisure time activity also decreased with the progression from low (men, 1.00; women, 1.00) to moderate (men, 0.83; women, 0.84) to high (men, 0.65; women, 0.75) activity levels (P<.001 for both men and women trends).

Study limitations included the self-report of physical activity, and that physical activity was recorded only once at baseline.

This study confirms that moderate or high levels of occupational or leisure-time physical activity have a negative association with the risk of HF among men and women,” the researchers concluded.