PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-12 (12)
 

Clipboard (0)
None

Select a Filter Below

Journals
Year of Publication
Document Types
1.  Resolution of ischemia with β-blocker in a patient with anomalous right coronary artery 
BMJ Case Reports  2011;2011:bcr0420114164.
Anomalous origin of right coronary artery (RCA) has been associated with angina, myocardial infarction and sudden death. Often these patients are referred for surgery. However, long-term β-blocker therapy instead of surgery has been used in some cases with success. The authors report a case of anomalous RCA where resolution of ischemia with β-blocker was objectively demonstrated on serial stress testing.
doi:10.1136/bcr.04.2011.4164
PMCID: PMC3207731  PMID: 22675030
2.  The Age-Dependent Contribution of Aortic Incident and Reflected Pressure Waves to Central Blood Pressure in African-Americans 
Aging is associated with increased central aortic systolic pressure (CSP) and pulse pressure which are predictive of cardiovascular events. Mechanisms implicated for higher central pressures include a higher forward incident pressure wave (P1), higher augmented pressure (AP), and shorter reflected wave round trip travel time (Tr). African-Americans (AA) have more frequent and deleterious blood pressure elevation. Using applanation tonometry, we studied the association of age and CSP with P1 and AP in 900 AA subjects. Data showed that in subjects ≤50 years old, CSP was mediated by AP but not P1 or Tr, whereas in those >50, CSP was mediated by both AP and P1 and to a lesser extent by Tr. Predictive models were significant (R2 = 0.97) for both age groups. In conclusion, wave reflection is the primary determinant of CSP in younger AA, while in older subjects, CSP is mediated by both the magnitude and timing of wave reflection as well as aortic impedance.
doi:10.4061/2011/585703
PMCID: PMC3163024  PMID: 21876787
3.  Narrowed Aortoseptal Angle Is Related to Increased Central Blood Pressure and Aortic Pressure Wave Reflection 
Cardiorenal Medicine  2012;2(3):177-183.
The left ventricular (LV) aortoseptal angle (ASA) decreases with age, and is associated with basal septal hypertrophy (septal bulge). Enhanced arterial pressure wave reflection is known to impact LV hypertrophy. We assessed whether ASA is related to central blood pressure (BP) and augmentation index (AI), a measure of the reflected pressure wave. We studied 75 subjects (age 62 ± 16 years; 66% female) who were referred for transthoracic echocardiography and had radial artery applanation tonometry within 24 h. Peripheral systolic BP (P-SBP), peripheral diastolic BP (P-DBP), and peripheral pulse pressure (P-PP) were obtained by sphygmomanometry. Central BPs (C-SBP, C-DBP, C-PP) and AI were derived from applanation tonometry. AI was corrected for heart rate (AI75). The basal septal wall thickness (SWT), mid SWT and ASA were measured using the parasternal long axis echocardiographic view. Mean ASA and AI75 were 117 ± 11° and 22 ± 11%, respectively. ASA correlated with AI75 (r = −0.31, p ≤ 0.01), C-SBP (r = −0.24, p = 0.04), C-PP (r = −0.29, p = 0.01), but only showed a trend towards significance with P-SBP (r = −0.2, p = 0.09) and P-PP (r = −0.21, p = 0.08). Interestingly, C-PP was correlated with basal SWT (r = 0.27, p = 0.02) but not with mid SWT (r = 0.19, p = 0.11). On multivariate linear regression analysis, adjusted for age, gender, weight, and mean arterial pressure, AI75 was an independent predictor of ASA (p = 0.02). Our results suggest that a narrowed ASA is related to increased pressure wave reflection and higher central BP. Further studies are needed to determine whether narrowed LV ASA is a cause or consequence of enhanced wave reflection and whether other factors are involved.
doi:10.1159/000338827
PMCID: PMC3433001  PMID: 22969773
Aortoseptal angle; Central blood pressure; Aortic wave reflection; Augmentation index
4.  Association between human immunodeficiency virus (HIV) infection and stiffness of the common carotid artery 
Background and purpose
Human immunodeficiency virus (HIV)-infected persons taking highly active antiretroviral therapy (HAART) may have an increased risk for cardiovascular-related events, although the underlying mechanism remains unclear. We tested the hypothesis that carotid arterial stiffness was higher among persons taking HAART compared to HAART-naïve and HIV-uninfected persons.
Methods
Between 2004 and 2006, we performed high resolution B-mode ultrasound on 2,789 HIV-infected and HIV-uninfected participants of the Women’s Interagency HIV Study (WIHS; 1865 women) and the Multicenter AIDS Cohort Study (MACS; 924 men) and determined carotid arterial distensibility, a direct measure of carotid arterial stiffness. We used generalized estimating equations to evaluate the association between distensibility and HIV infection, CD4+ cell count, and exposure to HAART adjusted for demographic, behavioral, and clinical characteristics.
Results
In multivariable analysis, distensibility was 4.3% lower (95% confidence interval (CI): -7.4% to -1.1%) among HIV-infected versus uninfected participants. Among HIV-infected participants with fewer than 200 CD4+ cells, distensibility was 10.5% lower (95% CI: -14.5% to -6.2%) than that among HIV-uninfected participants, and this effect did not differ significantly by cohort or race. Concurrent HAART use was independently associated with lower distensibility among MACS participants but not among WIHS participants.
Conclusions
Our finding that advanced HIV-related immunosuppression was associated with increased carotid arterial stiffness independent from the effects of traditional atherosclerosis risk factors suggests that the etiologic mechanism underlying reports of an increased cardiovascular disease risk among HIV-infected individuals might involve HIV-related immunosuppression leading to vascular dysfunction and arterial stiffening.
doi:10.1161/STROKEAHA.110.583856
PMCID: PMC2972735  PMID: 20798374
atherosclerosis; cardiovascular disease; carotid arteries; HIV; epidemiology
5.  Impact of sphingomyelin levels on coronary heart disease and left ventricular systolic function in humans 
Sphingomyelin (SM) is an abundant phospholipid in cell membranes and in lipoproteins. In human plasma, SM is mainly found in atherogenic lipoproteins; therefore, higher levels of SM may promote atherogenesis. We investigated the relations between plasma SM levels and the presence of angiographic coronary heart disease (CHD) and left ventricular systolic dysfunction. We studied 732 patients referred for coronary angiography. Median SM levels were higher among patients with CHD and in those with LV systolic dysfunction (LVEF<50%) than in patients without CHD or LV dysfunction. SM levels were significantly correlated with fibrinogen levels, diabetes, apoB, and triglyceride levels. On multivariate analyses, higher median SM levels were associated with a higher risk of CHD and lower LV ejection fraction. The pro-atherogenic property of plasma SM might be related to 1) CHD; 2) LV systolic dysfunction; and 3) metabolism of apoB-containing or triglyceride-rich lipoproteins.
doi:10.1186/1743-7075-8-25
PMCID: PMC3111338  PMID: 21521522
sphingomyelin; left ventricular ejection fraction; coronary heart disease; lipids
6.  Elevated NT-pro-BNP Levels Are Associated with Comorbidities among HIV-Infected Women 
AIDS Research and Human Retroviruses  2009;25(10):997-1004.
Abstract
HIV infection is associated with left ventricular (LV) dysfunction and accelerated atherosclerosis. These conditions result in elevation of plasma natriuretic peptide (NP) levels. The present study compares N-terminal-pro-BNP (NT-pro-BNP) levels in HIV-infected and -uninfected women and identifies factors influencingNT-pro-BNP levels in HIV-infected women. A total of 454 HIV-infected and 200 HIV-uninfected participants from the Women's Interagency HIV Study (WIHS) had NT-pro-BNP determination. Elevated NT-pro-BNP level was defined using previously determined age stratified cut-off values of >164 ng/liter (age <60 years) and >225 (age ≥ 60 years). HIV-infected women were older (41.6 ± 8.9 vs. 38.9 ± 10.5 years, p < 0.01) and were more likely to have anemia, hepatitis C virus (HCV) antibodies, and kidney dysfunction than HIV-uninfected women. HIV-infected women had significantly higher NT-pro-BNP levels (142.4 ± 524.8 vs. 73.6 ± 115.1 ng/liter, p = 0.01) and a higher prevalence of elevated NT-pro-BNP (12.1% vs. 7.5%; p = 0.08). In univariate analyses, elevated NT-pro-BNP was significantly associated with age, systolic BP, hypertension, anemia, triglyceride levels, kidney disease, and HCV seropositivity, but not HIV infection. In multivariate analysis, elevated NT-pro-BNP levels were significantly associated with anemia and kidney function, and had a borderline association with the presence of HCV antibodies. Among HIV-infected women, NT-pro-BNP levels were not independently associated with measures of severity of infection or with HAART use. Although HIV-infected women have higher NT-pro-BNP levels than HIV-uninfected women, the differences are due to non-HIV factors such as anemia, kidney disease, and HCV coinfection. These findings suggest that natriuretic peptide levels are a global marker of comorbidity in the setting of HIV infection.
doi:10.1089/aid.2009.0038
PMCID: PMC2791362  PMID: 19803714
7.  Arterial Wave Reflection in HIV-Infected and HIV-Uninfected Rwandan Women 
Abstract
To assess differences in arterial wave reflection, a marker of atherosclerosis, in HIV-positive and HIV-negative Rwandan women, applanation tonometry was performed on 276 HIV+ and 67 HIV− participants. Radial artery pressure waveforms were recorded and central aortic waveforms were derived by validated transfer function. Central augmentation index (C-AI), central pulse pressure (C-PP), and peripheral augmentation index (P-AI) were measured. HIV+ participants were younger and had lower diastolic blood pressure (BP) and 41% of the HIV+ women were taking antiretroviral therapy (ART). Mean C-AI and P-AI were significantly lower in HIV-infected than in uninfected participants (20.3 ± 12.0 vs. 25.5 ± 12.1, p = 0.002 and 74.6 ± 18.8 vs. 83.7 ± 20.0, p < 0.001). After age matching, C-AI, C-PP, and P-AI were similar among the groups. On multivariate analysis, age, heart rate, weight, and mean arterial pressure were independently associated with C-AI (R2 = 0.33, p < 0.0001). Among HIV-infected women, current CD4 count did not correlate with C-AI (Rho = −0.01, p = 0.84), C-PP (Rho = 0.09, p = 0.16), or P-AI (Rho = −0.01, p = 0.83). In conclusion, HIV infection was not associated with increased arterial wave reflection in women with little exposure to antiretroviral therapy and without CV risk factors. Whether long-term ART increases measures of arterial stiffness remains unknown.
doi:10.1089/aid.2008.0269
PMCID: PMC2858930  PMID: 19689195
8.  Positive Transcription Elongation Factor b (P-TEFb) Activity in Compensatory Myocardial Hypertrophy is Regulated by Cardiac Lineage Protein-1 
Circulation research  2009;104(12):1347-1354.
Emerging evidence illustrates the importance of the Positive Transcription Elongation Factor b (P-TEFb) in control of global RNA synthesis which constitutes a major feature of the compensatory response to diverse hypertrophic stimuli in cardiomyocytes. P-TEFb complex, composed of cyclin T and cdk9, is critical for elongation of nascent RNA chains via phosphorylation of the carboxyl terminal domain of RNA polymerase II (CTD RNA Pol II). We and others have shown that the activity of P-TEFb is inhibited by its association with CLP-1, the mouse homolog of human HEXIM1, in various physiological and pathological conditions. To investigate the mechanism of CLP-1’s control of the P-TEFb activity in cardiac hypertrophy, we used a transgenic mouse model of hypertrophy caused by over-expression of calcineurin in the heart. We observed that the level of CLP-1 associated with P-TEFb was reduced markedly in hypertrophic hearts. We also generated bigenic mice (MHC-cyclin T1/CLP-1+/−) by crossing MHC-cyclin T1 transgenic mice with CLP-1 heterozygote. The bigenic mice exhibit enhanced susceptibility to hypertrophy which is accompanied with an increase in cdk9 activity via an increase in serine 2 phosphorylation of CTD and an increase in GLUT1/GLUT4 ratio. These mice have compensated systolic function without evidence of fibrosis and reduced life span. These data suggest that the reduced level of CLP-1 introduced in the background of elevated levels of cyclin T1 elevates de-repression of P-TEFb activity and emphasizes the importance of CLP-1’s role in the mechanism governing compensatory hypertrophy in cardiomyocytes.
doi:10.1161/CIRCRESAHA.108.191726
PMCID: PMC2774227  PMID: 19443839
myocardial hypertrophy; transcriptional elongation; CLP-1; HEXIM1
9.  The Association of HIV Infection with Left Ventricular Mass/Hypertrophy 
Left ventricular hypertrophy (LVH) is an independent predictor of major cardiovascular events. Cardiovascular risk is increased among human immunodeficiency virus (HIV)-infected patients. To assess LV mass/hypertrophy in HIV infection, 654 women enrolled in the Women's Interagency HIV Study underwent transthoracic echocardiography. There were 454 HIV-infected and 200 uninfected women, mean age 40.8 ± 9.3 years. LV mass/height2.7 was similar between the HIV-infected and the HIV-uninfected groups (41.4 ± 11.1 vs. 39.9 ± 10.3 g/h2.7; p = 0.37). The prevalence of LVH was similar between the two groups (LVH by LV mass/height2.7 criteria 15.0% vs. 13.0%, p = 0.29). Relative wall thickness (RWT), defined as the ratio of LV wall thickness to cavity diameter, was also similar between the HIV-infected and HIV-uninfected groups (0.36 ± 0.05 vs. 0.37 ± 0.06, p = 0.16). On multiple linear regression analysis adjusting for age, W/H ratio, triceps skinfold thickness, systolic/diastolic BP, diabetes, hypertension and dyslipidemia; HIV status (b = 2.08, p = 0.02, CI 0.27–3.88); weight (b per kg = 0.15, p<0.01, CI 0.08–0.22); and smoking duration (b per one-year increase = 0.08, p = 0.03, CI 0.01–0.16) were independent correlates of LV mass/height2.7 (Model R2 = 0.20, p<0.001). Weight (aOR = 1.04, CI 1.01–1.06) and smoking duration (aOR = 1.03, CI 1.01–1.06) were independent correlates of LVH. Being HIV negative, increased age, increased triceps skinfold thickness, and higher W/H ratio were independent correlates of higher RWT. Among HIV-infected women, higher LV mass was not associated with a history of AIDS-defining illness, nadir CD4+ count <200 cells/μl, or with the duration of highly active antiretroviral therapy (HAART). Women taking NRTIs had higher LV mass. Higher RWT was associated with current CD4+ count. In conclusion, HIV infection is associated with greater LV mass but not with a higher prevalence of LVH. Among HIV-infected women, RWT, but not LV mass, is associated with the degree of immunosuppression.
doi:10.1089/aid.2008.0170
PMCID: PMC2801578  PMID: 19397399
10.  The Association of HIV Infection with Left Ventricular Mass/Hypertrophy 
Abstract
Left ventricular hypertrophy (LVH) is an independent predictor of major cardiovascular events. Cardiovascular risk is increased among human immunodeficiency virus (HIV)-infected patients. To assess LV mass/hypertrophy in HIV infection, 654 women enrolled in the Women's Interagency HIV Study underwent transthoracic echocardiography. There were 454 HIV-infected and 200 uninfected women, mean age 40.8 ± 9.3 years. LV mass/height2.7 was similar between the HIV-infected and the HIV-uninfected groups (41.4 ± 11.1 vs. 39.9 ± 10.3 g/h2.7; p = 0.37). The prevalence of LVH was similar between the two groups (LVH by LV mass/height2.7 criteria 15.0% vs. 13.0%, p = 0.29). Relative wall thickness (RWT), defined as the ratio of LV wall thickness to cavity diameter, was also similar between the HIV-infected and HIV-uninfected groups (0.36 ± 0.05 vs. 0.37 ± 0.06, p = 0.16). On multiple linear regression analysis adjusting for age, W/H ratio, triceps skinfold thickness, systolic/diastolic BP, diabetes, hypertension and dyslipidemia; HIV status (b = 2.08, p = 0.02, CI 0.27–3.88); weight (b per kg = 0.15, p < 0.01, CI 0.08–0.22); and smoking duration (b per one-year increase = 0.08, p = 0.03, CI 0.01–0.16) were independent correlates of LV mass/height2.7 (Model R2 = 0.20, p < 0.001). Weight (aOR = 1.04, CI 1.01–1.06) and smoking duration (aOR = 1.03, CI 1.01–1.06) were independent correlates of LVH. Being HIV negative, increased age, increased triceps skinfold thickness, and higher W/H ratio were independent correlates of higher RWT. Among HIV-infected women, higher LV mass was not associated with a history of AIDS-defining illness, nadir CD4+ count <200 cells/μl, or with the duration of highly active antiretroviral therapy (HAART). Women taking NRTIs had higher LV mass. Higher RWT was associated with current CD4+ count. In conclusion, HIV infection is associated with greater LV mass but not with a higher prevalence of LVH. Among HIV-infected women, RWT, but not LV mass, is associated with the degree of immunosuppression.
doi:10.1089/aid.2008.0170
PMCID: PMC2801578  PMID: 19397399
11.  Elevated NT-pro-BNP Levels Are Associated with Comorbidities among HIV-Infected Women 
AIDS research and human retroviruses  2009;25(10):997-1004.
HIV infection is associated with left ventricular (LV) dysfunction and accelerated atherosclerosis. These conditions result in elevation of plasma natriuretic peptide (NP) levels. The present study compares N-terminal-pro-BNP (NT-pro-BNP) levels in HIV-infected and -uninfected women and identifies factors influencing NT-pro-BNP levels in HIV-infected women. A total of 454 HIV-infected and 200 HIV-uninfected participants from the Women’s Interagency HIV Study (WIHS) had NT-pro-BNP determination. Elevated NT-pro-BNP level was defined using previously determined age stratified cut-off values of >164 ng/liter (age <60 years) and >225 (age ≥60 years). HIV-infected women were older (41.6 ± 8.9 vs. 38.9 ± 10.5 years, p <0.01) and were more likely to have anemia, hepatitis C virus (HCV) antibodies, and kidney dysfunction than HIV-uninfected women. HIV-infected women had significantly higher NT-pro-BNP levels (142.4 ± 524.8 vs. 73.6 ± 115.1 ng/liter, p = 0.01) and a higher prevalence of elevated NT-pro-BNP (12.1% vs. 7.5%; p = 0.08). In univariate analyses, elevated NT-pro-BNP was significantly associated with age, systolic BP, hypertension, anemia, triglyceride levels, kidney disease, and HCV seropositivity, but not HIV infection. In multivariate analysis, elevated NT-pro-BNP levels were significantly associated with anemia and kidney function, and had a borderline association with the presence of HCV antibodies. Among HIV-infected women, NT-pro-BNP levels were not independently associated with measures of severity of infection or with HAART use. Although HIV-infected women have higher NT-pro-BNP levels than HIV-uninfected women, the differences are due to non-HIV factors such as anemia, kidney disease, and HCV coinfection. These findings suggest that natriuretic peptide levels are a global marker of comorbidity in the setting of HIV infection.
doi:10.1089/aid.2009.0038
PMCID: PMC2791362  PMID: 19803714
12.  Plasma PLTP activity is inversely associated with HDL-C levels 
Phospholipid transfer protein (PLTP) is an important modulator of lipoprotein metabolism, including interparticle phospholipid transfer, remodeling of HDL, cholesterol and phospholipid efflux from peripheral tissues, and the production of hepatic VLDL. PLTP also plays an important role in inflammation and oxidative stress. Accordingly, PLTP has been implicated in the development of atherosclerosis. In this study, we evaluated the association between PLTP activity and lipoprotein metabolism in a Chinese patients cohort with or without coronary heart disease (CHD group n = 407, control group n = 215), the PLTP activity was measured and PLTP genotyping was screened for sequence anomalies by PCR. We found that human plasma PLTP activity was negatively associated with plasma HDL and apoA-I levels, and positively associated with plasma TG, apoB and apoE levels. We also found that PLTP rs2294213 polymorphism was tended to be associated with increased plasma PLTP activity.
doi:10.1186/1743-7075-6-49
PMCID: PMC2793253  PMID: 19948027

Results 1-12 (12)