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ABSTRACT: OBJECTIVES: The purpose of this study was to investigate the associations of traditional risk factors and longitudinal measures of HIV disease severity with risk of incident atrial fibrillation (AF) in a contemporary cohort of HIV-infected individuals. BACKGROUND: Cardiovascular disease is common in HIV-infected persons; however, the most common cardiac arrhythmia, AF, has not been adequately studied in this population. METHODS: We studied a national sample of 30,533 HIV-infected veterans followed in the Veterans Affairs HIV Clinical Case Registry from 1996-2011. We examined the independent associations of demographic characteristics, time-updated comorbidities, and time-updated clinical measurements including CD4+ cell count and viral load with the outcome of incident AF using proportional-hazards regression for multivariable analysis. RESULTS: Over a median follow-up of 6.8 years, 780 (2.6%) patients developed AF. After multivariable adjustment for traditional risk factors, a lower CD4+ cell count (<200 compared with >350 cells/mm(3); hazard ratio [HR], 1.4; 95% confidence interval [CI], 1.1-1.8; p=0.018) and higher viral load (>100,000 compared with <500 copies/mL; HR, 1.7; 95% CI, 1.2-2.4; p=0.002) were independently associated with increased risk of incident AF. Additional risk factors independently associated with risk of AF included older age, White race, coronary artery disease, congestive heart failure, alcoholism, proteinuria, reduced kidney function and hypothyroidism. CONCLUSIONS: In a large HIV-infected cohort, markers of HIV disease severity represented by low CD4+ cell count and high viral load, assessed by multiple time-updated measures, were independently associated with development of AF.
Journal of the American College of Cardiology 04/2013; · 14.16 Impact Factor
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Hiroyu Hatano,
Rebecca Scherzer,
Yuaner Wu,
Kara Harvill,
Kristinalisa Maka,
Rebecca Hoh,
Elizabeth Sinclair,
Sarah Palmer,
Jeffrey N Martin,
Michael P Busch,
Steven G Deeks, Priscilla Y Hsue
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ABSTRACT: : To determine whether intensification with raltegravir improves endothelial function in antiretroviral-treated HIV-infected individuals.
: Randomized, double-blinded, placebo-controlled study.
: Fifty-six subjects with treatment-mediated viral suppression for at least 1 year were randomized to add 400 mg of raltegravir twice daily or matching placebo for 24 weeks. The primary endpoint was the difference in rate of change in endothelial function [as assessed by flow-mediated vasodilation (FMD) of the brachial artery] from baseline to week 24 between the raltegravir and placebo groups. Linear mixed models were used to evaluate the association of treatment group with changes in FMD, immune activation, and measures of viral persistence.
: At baseline, the median CD4 T-cell count was 498 cells/mm, nadir CD4 T-cell count was 191 cells/mm, duration of HIV infection was 18 years, FMD was 3.3%, and hyperemic velocity (a marker of microvascular function) was 68.3 cm. There were no significant differences between treatment groups in rate of change in FMD (raltegravir group: +0.032% per week, placebo group: +0.023% per week; P = 0.60). There were also no differences between treatment groups in rate of change in hyperemic velocity, immune activation, or viral persistence. In multivariable analysis, older age, longer duration of HIV infection, and current abacavir use were associated with lower FMD. Lower CD4 T-cell count and current abacavir use were associated with lower hyperemic velocity.
: The addition of raltegravir to suppressive antiretroviral therapy did not have a significant impact on cardiovascular risk, as assessed by endothelial function (ClinicalTrials.gov NCT00843713).
JAIDS Journal of Acquired Immune Deficiency Syndromes 08/2012; 61(3):317-25. · 4.43 Impact Factor
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JAMA The Journal of the American Medical Association 07/2012; 308(4):405-6. · 30.03 Impact Factor
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ABSTRACT: Doppler echocardiography is used to screen for HIV-related pulmonary arterial hypertension (HRPAH). We studied patients with HIV infection to determine the accuracy of Doppler echocardiography-estimated pulmonary artery systolic pressure (PASP) compared with PASP measured during right heart catheterization. Doppler echocardiography-estimated PASP was inaccurate in 19.7% of cases. Using Doppler echocardiography-estimated PASP, one in three patients with HRPAH was missed. Doppler echocardiography estimates of PASP are not accurate in patients with HIV.
AIDS (London, England) 07/2012; 26(15):1967-9. · 4.91 Impact Factor
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ABSTRACT: Cardiovascular complications are more common in human immunodeficiency virus-infected individuals than in age-matched uninfected individuals. Antiretroviral therapy reduces the risk of cardiovascular complications, suggesting that viral replication directly or indirectly causes vascular disease. Long-term effective antiretroviral therapy does not fully restore vascular health, and treated adults continue to have higher-than-expected rates of disease progression. Although this excess risk during therapy is likely due to multiple factors, a growing body of evidence suggests that chronic inflammation, which persists during effective antiretroviral therapy, is directly and causally associated with vascular dysfunction and the accelerated development of atherosclerosis.
The Journal of Infectious Diseases 06/2012; 205 Suppl 3:S375-82. · 6.41 Impact Factor
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ABSTRACT: The aim of this study was to investigate whether exposure to a range of relatively low concentrations of aged secondhand smoke (SHS), similar to those encountered commonly in the community, would impair endothelial function in a concentration-dependent manner.
Exposure to SHS impairs endothelial function in humans. The concentration-dependent relationship for aged SHS effects on endothelial function after an exposure of short duration is unknown.
Thirty-three healthy nonsmokers were exposed to 1 of 2 low levels of aged SHS or to conditioned filtered air for 30 min. The primary end point was change in maximal percent brachial artery flow-mediated dilation after exposure.
In a linear regression model for each increase in SHS exposure by 100 μg/m(3) respirable suspended particles, the absolute maximal percent brachial artery flow-mediated dilation was reduced by 0.67%. We did not find evidence of a threshold for the effect of SHS on flow-mediated dilation.
Short-term exposure to real-world levels of aged SHS for 30 min resulted in a concentration-dependent decrease in endothelial function as measured by flow-mediated dilation.
Journal of the American College of Cardiology 05/2012; 59(21):1908-13. · 14.16 Impact Factor
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ABSTRACT: Excess risk of cardiovascular disease occurs in effectively treated individuals with human immunodeficiency virus (HIV) infection. Although elevated plasma D-dimer levels are associated with increased morbidity and mortality, the impact of HIV infection on coagulation in vivo has not been well studied.
We measured D-dimers, antithrombin, endogenous thrombin potential (ETP; a functional measure of thrombin generation in vitro), thrombin/antithrombin complexes (TAT; a measure of thrombin generation in vivo), tissue factor, prothrombin fragment 1 + 2 (F1+2), and normalized APC sensitivity ratio (nAPCsr) in 199 HIV-positive men who were receiving antiretroviral therapy and had an undetectable HIV RNA level, in 79 HIV-positive untreated men, and in 39 uninfected controls.
Median antithrombin levels were higher while the ETP was lower among HIV-infected adults (treated and untreated), compared with controls. There were few differences between coagulation markers in the 2 HIV groups. Compared with controls, the nAPCsr was lower in treated men and the TAT level was lower in untreated individuals. We observed little difference among measured levels of D-dimer, tissue factor, or F1+2 between HIV-infected individuals and controls. Antiretroviral therapy exposure was associated with a lower antithrombin level, a lower nAPCsr, and a lower ETP, while history of opportunistic infection was associated with a higher nAPCsr.
HIV infection is associated with decreased thrombin generation, as measured by the ETP, and an increased antithrombin level. These data suggest that HIV infection may not be associated with increased propensity toward clotting, as has been suggested on the basis of isolated measures of D-dimer levels.
Clinical Infectious Diseases 04/2012; 54(8):1196-203. · 9.15 Impact Factor
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ABSTRACT: Shear stress gradients and inflammation have been causally associated with atherosclerosis development in carotid bifurcation regions. The mechanism underlying higher levels of carotid intima-media thickness observed among HIV-infected individuals remains unknown.
We measured carotid intima-media thickness progression and development of plaque in the common carotid, bifurcation region, and internal carotid artery in 300 HIV-infected persons and 47 controls. The median duration of follow-up was 2.4 years. When all segments were included, the rate of intima-media thickness progression was greater in HIV-infected subjects compared with controls after adjustment for traditional risk factors (0.055 vs. 0.024 mm/year, P=0.016). Rate of progression was also greater in the bifurcation region (0.067 vs. 0.025 mm/year, P=0.042) whereas differences were smaller in the common and internal regions. HIV-infected individuals had a greater incidence of plaque compared with controls in the internal (23% vs. 6.4%, P=0.0037) and bifurcation regions (34% vs. 17%, P=0.014). Among HIV-infected individuals, the rate of progression in the bifurcation region was more rapid compared with the common carotid, internal, or mean intima-media thickness; in contrast, progression rates among controls were similar at all sites. Baseline hsCRP was elevated in HIV-infected persons and was a predictor of progression in the bifurcation region.
Atherosclerosis progresses preferentially in the carotid bifurcation region in HIV-infected individuals. hsCRP, a marker of inflammation, is elevated in HIV and is associated with progression in the bifurcation region. These data are consistent with a model in which the interplay between hemodynamic shear stresses and HIV-associated inflammation contribute to accelerated atherosclerosis. (J Am Heart Assoc. 2012;1:jah3-e000422 doi: 10.1161/JAHA.111.000422.)
URL: http://clinicaltrials.gov. Unique identifier: NCT01519141.
Journal of the American Heart Association. 04/2012; 1(2).
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ABSTRACT: HIV-infected individuals are at high risk of developing cardiovascular disease. Whether earlier initiation of HIV therapy at higher CD4 cell counts has any effect on cardiovascular risk as assessed by endothelial function is unknown.
Cross-sectional study of 74 antiretroviral-treated men with undetectable plasma HIV RNA levels.
Participants underwent noninvasive assessment of endothelial function using brachial artery flow-mediated dilation (FMD). The association of nadir and current CD4 T-cell count with FMD was assessed using multivariable linear regression.
The median age was 47 years [interquartile range (IQR) 42-55], median current CD4 T-cell count was 659 cells/μl (IQR 542-845), and nadir CD4 cell count was 314 cells/μl (IQR 150-490). Twenty-eight percent had hypertension, and 32% hyperlipidemia. Nadir CD4 T-cell count less than 350 cells/μl was associated with lower FMD in age-adjusted and race-adjusted analyses and remained an independent predictor of FMD after adjustment for cardiovascular risk factors (hypertension, diabetes, smoking, hyperlipidemia) and HIV-related characteristics (HIV duration, HAART duration). After multivariable adjustment, individuals with nadir CD4 T-cell count less than 350 cells/μl had a 1.22% lower FMD compared with those with higher T-cell counts [95% confidence interval (CI) -2.20 to -0.19, P=0.02]. Proximal CD4 T-cell count showed little association with FMD.
Among treated HIV-infected individuals, nadir CD4 T-cell count less than 350 cells/μl is independently associated with lower FMD, suggesting that delayed therapy results in sustained harm to endothelial function. Our data support future prospective studies evaluating cardiovascular effects of HAART initiation at higher CD4 cell counts.
AIDS (London, England) 02/2012; 26(9):1115-20. · 4.91 Impact Factor
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ABSTRACT: HIV-infected individuals are at increased risk for myocardial infarction. Given observations that cytomegalovirus (CMV) infection, CMV-specific T cells, and CX3CR1 have each been associated with atherosclerosis, we hypothesized that CMV-induced T-cell immunopathology could contribute to HIV-associated atherosclerosis.
We measured the expression of CX3CR1 on peripheral blood mononuclear cells and its association with carotid artery intima-media thickness (IMT) in 29 HIV-infected individuals and 48 uninfected controls. We analyzed the phenotype and specificity of CX3CR1(+)CD4(+) T cells, the production of CX3CL1 (the ligand of CX3CR1) by CMV-infected endothelial cells in vitro, and the migration of CD4(+) T cells induced by CX3CL1.
The progression of atherosclerosis in HIV-infected individuals, as assessed by longitudinal measurements of carotid IMT, was associated with a high frequency of CD4(+) T cells that express the chemokine receptor CX3CR1. Such CD4(+)CX3CR1(+) T cells were antigen-primed, produced high levels of pro-inflammatory cytokines, and composed the majority of the CMV-specific CD4(+) T cells. CMV-stimulated CD4(+) T cells were also found to induce the production of CX3CL1 (the ligand for CX3CR1) by human arterial endothelial cells, driving the transendothelial migration of pro-inflammatory CD4(+) T cells. Finally, we observed that CD4(+)CX3CR1(+) T cells could be localized to the coronary arterial wall in HIV disease.
HIV-associated atherosclerosis may be driven by a positive feedback pathway in which a high frequency of antigen-stimulated, CMV-specific CD4(+)CX3CR1(+) T cells induce endothelial cells to secrete CX3CL1, which itself drives progressive infiltration of the arterial wall by pro-inflammatory cells.
AIDS (London, England) 02/2012; 26(7):805-14. · 4.91 Impact Factor
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Priscilla Y Hsue,
Karen Ordovas,
Theodore Lee,
Gautham Reddy,
Michael Gotway,
Amanda Schnell,
Jennifer E Ho,
Van Selby,
Erin Madden,
Jeffrey N Martin,
Steven G Deeks,
Peter Ganz,
David D Waters
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ABSTRACT: Subjects infected with human immunodeficiency virus (HIV) have increased risk for atherosclerosis. Carotid artery intima-media thickness (IMT) assessed using ultrasound and coronary artery calcium (CAC) detected using computed tomography predict cardiovascular risk in the general population; however, their usefulness and comparability in patients with HIV are less well defined. The purpose of this study was to compare IMT and CAC in the detection of atherosclerosis in subjects with HIV. CAC and IMT were measured in 253 HIV-infected and 58 uninfected adults. Associations among HIV-related factors, traditional risk factors, and CAC and IMT were evaluated. The distribution of IMT among subjects with and without CAC was compared. Among the patients with HIV, 37% had detectable CAC compared to 28% of controls (p = 0.19); 16% of the patients with HIV had CAC >100 compared to 5% of controls (p = 0.03). With either detectable or undetectable CAC, HIV-infected subjects had higher IMT compared to controls (1.02 ± 0.34 vs 0.78 ± 0.12 mm, p <0.0001), even after adjustment for traditional risk factors. Among those with undetectable CAC, 34% of patients with HIV had markedly increased IMT (≥1 mm) compared to no controls (p <0.0001). HIV-related factors were associated with IMT but not with CAC. In conclusion, patients with HIV and controls had similar rates of detectable CAC, while absolute CAC scores were modestly higher in the HIV group. Conversely, carotid IMT detected advanced subclinical atherosclerosis in patients with HIV even in the absence of CAC. Thus, with HIV, IMT is associated with disease-related factors and may be a more sensitive indicator of subclinical atherosclerosis than CAC.
The American journal of cardiology 12/2011; 109(5):742-7. · 3.58 Impact Factor
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Archives of internal medicine 11/2011; 172(2):193-4. · 11.46 Impact Factor
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Sharilyn Almodovar,
Rob Knight,
Amanda A Allshouse,
Sarah Roemer,
Catherine Lozupone,
Daniel McDonald,
Jeremy Widmann,
Norbert F Voelkel,
Robert J Shelton,
Edu B Suarez,
Kenneth W Hammer,
Cecile Goujard,
Nicola Petrosillo,
Gerald Simonneau, Priscilla Y Hsue,
Marc Humbert,
Sonia C Flores
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ABSTRACT: Severe pulmonary hypertension (PH) associated with vascular remodeling is a long-term complication of HIV infection (HIV-PH) affecting 1/200 infected individuals vs. 1/200,000 frequency in the uninfected population. Factors accounting for increased PH susceptibility in HIV-infected individuals are unknown. Rhesus macaques infected with chimeric SHIVnef virions but not with SIV display PH-like pulmonary vascular remodeling suggesting that HIV-Nef is associated with PH; these monkeys showed changes in nef sequences that correlated with pathogenesis after passage in vivo. We further examined whether HIV-nef alleles in HIV-PH subjects have signature sequences associated with the disease phenotype. We evaluated specimens from participants with and without HIV-PH from European Registries and validated results with samples collected as part of the Lung-HIV Studies in San Francisco. We found that 10 polymorphisms in nef were overrepresented in blood cells or lung tissue specimens from European HIV-PH individuals but significantly less frequent in HIV-infected individuals without PH. These polymorphisms mapped to known functional domains in Nef. In the validation cohort, 7/10 polymorphisms in the HIV-nef gene were confirmed; these polymorphisms arose independently from viral load, CD4(+) T cell counts, length of infection, and antiretroviral therapy status. Two out of 10 polymorphisms were previously reported in macaques with PH-like pulmonary vascular remodeling. Cloned recombinant Nef proteins from clinical samples down-regulated CD4, suggesting that these primary isolates are functional. This study offers new insights into the association between Nef polymorphisms in functional domains and the HIV-PH phenotype. The utility of these polymorphisms as predictors of PH should be examined in a larger population.
AIDS research and human retroviruses 11/2011; 28(6):607-18. · 2.18 Impact Factor
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ABSTRACT: Despite the increased risk of myocardial infarction, aortic dissection, and arrhythmias in patients with hypertension who use cocaine, the hemodynamic and arrhythmogenic effects of cocaine use have not been well characterized in this population. The authors hypothesized that patients with hypertension demonstrate extreme, transient changes in arterial pressures as well as new arrhythmic activity during cocaine use. Ambulatory blood pressures, heart rates, and electrocardiograms (AECGs) were recorded for 48 hours in 10 patients with a history of hypertension who smoke cocaine. Active cocaine use was identified through patient diaries and manual activation of the blood pressure cuff. Of the 10 patients studied (6 men, 7 African Americans, age 49±8 years), 8 were taking antihypertensive medications. The mean blood pressure prior to cocaine use was 126/77 mm Hg and average increase in systolic, diastolic, and mean arterial pressure after use was 74 mm Hg, 30 mm Hg, and 45 mm Hg, respectively (P<.0001 for all). There was no significant change in heart rate. AECGs demonstrated arrhythmic activity during cocaine use, including 6 patients with increased atrial and ventricular ectopy, 2 patients with episodes of nonsustained atrial tachycardia, and 1 patient with 3 episodes of nonsustained monomorphic ventricular tachycardia. Cocaine use resulted in extreme elevations in arterial pressures in patients with hypertension taking medication. Cocaine use was also associated with an increase in arrhythmic activity. These findings may underlie the heightened risk of myocardial infarction, aortic dissection, and potentially lethal arrhythmias in patients with hypertension who use cocaine.
Journal of Clinical Hypertension 10/2011; 13(10):744-9. · 1.83 Impact Factor
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Clinical Infectious Diseases 07/2011; 53(1):96; author reply 96-7. · 9.15 Impact Factor
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ABSTRACT: Infection with HIV increases the risk for lung diseases, including noninfectious pulmonary hypertension (PH). HIV-associated PH (HIV-PH) is an important lung disease in HIV-infected persons who live longer with antiretrovirals. The early stages of HIV-PH may be overlooked by healthcare providers due to nonspecific symptoms, including progressive dyspnea and nonproductive cough. HIV-PH may be detected via chest radiographs, CT scans, or electrocardiograms, but Doppler echocardiography is the most useful screening test to identify candidates for right heart catheterization. HIV-PH has a poor prognosis with high mortality; improved biomarkers to identify earlier stages of PH would benefit clinical care. The HIV-PH mechanism remains unknown, but HIV proteins such as Tat and Nef may play a role. HIV-1 Nef is a broad-spectrum adaptor protein that may affect HIV-infected and uninfected pulmonary vascular cells. Studies in macaques suggest that Nef is important in HIV-PH pathogenesis because monkeys infected with a chimeric simian immunodeficiency virus (SIV) expressing HIV-nef (SHIVnef) alleles, but not monkeys infected with the native SIV, develop pulmonary vascular remodeling. Four consistent amino acid mutations arose spontaneously in Nef passaged in the monkeys. To translate these findings to humans, one research endeavor of the Lung HIV Study focuses on the identification of HIV nef mutations in HIV-infected individuals with PH compared with HIV-infected normotensive patients. We present some of the preliminary evidence. Ongoing longitudinal studies will establish the connection between Nef mutations and the propensity for HIV-PH.
Proceedings of the American Thoracic Society 06/2011; 8(3):308-12.
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ABSTRACT: We observed an independent association between vitamin D insufficiency and higher carotid intima-media thickness in a cross-sectional analysis of 139 HIV-infected persons. If confirmed, these findings support a clinical trial of vitamin D supplementation to reduce cardiovascular events in HIV-infected persons.
Clinical Infectious Diseases 01/2011; 52(7):941-4. · 9.15 Impact Factor
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ABSTRACT: HIV infection is associated with increased rates of cardiovascular disease. We sought to evaluate whether initiation of HIV therapy at higher nadir CD4(+) T-cell counts might reduce cardiovascular risk, as measured by arterial stiffness.
We conducted a cross-sectional study of 80 HIV-infected men who were antiretroviral-treated with undetectable plasma HIV RNA levels.
Participants underwent noninvasive assessment of arterial stiffness by pulse wave analysis (augmentation index normalized for heart rate of 75 bpm) and carotid-femoral pulse wave velocity, both sensitive measures of cardiovascular risk. A generalized linear model was used to determine the relationship between cardiovascular and HIV-related predictors, and arterial stiffness.
In unadjusted analyses, predictors of arterial stiffness included age, blood pressure, antihypertensive medication use, and nadir CD4(+) T-cell count below 350 cells/microl (all P < 0.05). After adjusting for both cardiovascular risk factors (age, blood pressure, antihypertensive medication use, diabetes, hypercholesterolemia, and smoking) and HIV-related covariates, nadir CD4(+) T-cell count below 350 cells/microl was independently associated with a 0.41 m/s increase in pulse wave velocity (95% confidence interval 0.03-0.79, P = 0.03) and a 7.3% increase in augmentation index (augmentation index normalized for heart rate of 75 bpm; 95% confidence interval 2.6-11.9, P = 0.003). Neither duration of antiretroviral therapy nor exposure to protease inhibitors was associated with arterial stiffness.
Among treated HIV-infected individuals, arterial stiffness is independently associated with both traditional cardiovascular risk factors as well as a low nadir CD4(+) T-cell count. Our data suggest that cardiovascular risk among HIV-infected individuals could be reduced through early initiation of antiretroviral therapy, before CD4 T-cell counts are depressed, a concept that should be tested prospectively in future studies.
AIDS (London, England) 07/2010; 24(12):1897-905. · 4.91 Impact Factor
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ABSTRACT: BACKGROUND: Patients with HIV have increased risk for cardiovascular disease, but the underlying mechanisms remain unknown. The purpose of this study was to determine the prevalence of echocardiographic abnormalities among asymptomatic HIV-infected individuals compared with HIV-uninfected individuals. Methods/Results- We performed echocardiography in 196 HIV-infected adults and 52 controls. Left ventricular ejection fraction, left ventricular mass indexed to the body surface area, and diastolic function were assessed according to American Society of Echocardiography standards. Left ventricular mass index was higher in HIV-infected patients (77.2 g/m(2) in patients with HIV versus 66.5 g/m(2) in controls, P<0.0001). Left ventricular ejection fraction was similar in both groups. Eight (4%) of the patients with HIV had evidence of left ventricular systolic dysfunction (defined as an EF <50%) versus none of the controls; 97 (50%) had mild diastolic dysfunction compared with 29% of the HIV-uninfected subjects (P=0.008). After adjustment for hypertension and race, HIV-infected participants had a mean 8 g/m(2) larger left ventricular mass index compared with controls (P=0.001). Higher left ventricular mass index was independently associated with lower nadir CD4 T-cell count, suggesting that immunodeficiency may play a role in this process. After adjustment for age and traditional risk factors, patients with HIV had a 2.4 greater odds of having diastolic dysfunction as compared with controls (P=0.019). CONCLUSIONS: HIV-infected patients had a higher prevalence of diastolic dysfunction and higher left ventricular mass index compared with controls. These differences were not readily explained by differences in traditional risk factors and were independently associated with HIV infection. These results suggest that contemporary asymptomatic patients with HIV manifest mild functional and morphological cardiac abnormalities, which are independently associated with HIV infection.
Circulation Heart Failure 11/2009; 3(1):132-9. · 6.29 Impact Factor
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Circulation 10/2009; 120(16):1555-7. · 14.74 Impact Factor
