[Show abstract][Hide abstract] ABSTRACT: New approaches to the definition and treatment of hypertension have increased emphasis on reducing overall cardiovascular risk and on targeting the underlying mechanisms of cardiovascular disease. During the past several decades, renin-angiotensin-aldosterone system (RAAS) activation has emerged as an important factor in the pathophysiology of endothelial dysfunction and cardiovascular disease (CVD). Angiotensin-converting enzyme inhibitors (ACEIs) have well-established efficacy for treating CVD, but their use may be limited by intolerable side effects, such as cough and angioedema. Angiotensin II receptor blockers (ARBs), a different class of RAAS inhibitors, are considered a viable alternative to ACEIs. Clinical trials have further elucidated the role of ARBs in CVD. This article reviews the mechanism of action of ARBs and selected clinical trials of ARBs in CVD.
Preview · Article · May 2012 · Journal of Renin-Angiotensin-Aldosterone System
[Show abstract][Hide abstract] ABSTRACT: We examined the relations of central adiposity with left ventricular (LV) diastolic dysfunction in men and women who participated in the Baltimore Longitudinal Study of Aging, a prospective community-based study of older persons. The sample for this cross-sectional analysis included 399 women and 370 men. Central adiposity was estimated using the waist circumference (WC) and global adiposity using the body mass index (BMI). Using data from a comprehensive echocardiographic study that included tissue Doppler imaging, diastolic function was graded according to 3 parameters (E/A ratio, E/Em ratio, and left atrial volume index). In the logistic regression models adjusted for age, gender, cardiovascular risk factors, and hemodynamic parameters, WC and BMI were both independently associated with LV diastolic dysfunction. However, when both WC and BMI were in the same model, only WC remained significantly associated with LV diastolic dysfunction (odds ratio 1.04, 95% confidence interval 1.01 to 1.08, p = 0.02). In the gender-stratified analyses, WC was significantly associated with LV diastolic dysfunction-independently of BMI-in women (odds ratio 1.08, 95% confidence interval 1.04 to 1.14, p <0.001) but not in men (odds ratio 1.00, 95% confidence interval 0.95 to 1.05, p = 0.91). Additional adjustment for LV mass index failed to modify these relations. In conclusion, the adverse effect of central adiposity on LV diastolic function was independent of general adiposity and more pronounced among women. The effect of visceral adiposity on LV diastolic dysfunction would benefit from confirmation in longitudinal studies.
Full-text · Article · Jan 2012 · The American journal of cardiology
[Show abstract][Hide abstract] ABSTRACT: Extracardiac comorbidities are common in patients with heart failure and a preserved ejection fraction (HFPEF). We sought to evaluate the relationship between comorbidities and ventricular structure and function in patients with HFPEF through evaluation of pressure-volume analysis.
Two hundred twenty Chinese patients with a preserved ejection fraction who were either healthy (n = 75), hypertensive without heart failure (HTN; n = 89), or hypertensive with HFPEF (HFPEF; n = 56) were studied. Using echocardiographic measures, estimated end-systolic and end-diastolic pressure-volume relationships, and the area between them as a function of EDP, the isovolumic pressure-volume areas (PVA(iso)), were calculated. Ventricular capacitance, as measured by V(30), was larger in patients with HFPEF compared with normal control subjects and tended to be larger compared with hypertensive control subjects. The presence of diabetes and renal insufficiency was independently associated with greater ventricular capacitance in patients with HFPEF. The PVA(iso) was increased in patients with HFPEF compared with HTN and normal control subjects, and in particular, it was increased in HFPEF patients with multiple comorbidities.
The presence of comorbid conditions is associated with altered pressure-volume relations and enhanced pump function in subjects with HFPEF, supporting an important role for extracardiac comorbidities in the pathophysiology of patients with this condition.
[Show abstract][Hide abstract] ABSTRACT: In the current era of immunosuppressive medications there is increased observed incidence of graft dysfunction in the absence of known histological criteria of rejection after heart transplantation. A noninvasive molecular expression diagnostic test was developed and validated to rule out histological acute cellular rejection. In this paper we present for the first time, longitudinal pattern of changes in this novel diagnostic test score along with QTc-interval in a patient who was admitted with unexplained graft dysfunction. Patient presented with graft failure with negative findings on all known criteria of rejection including acute cellular rejection, antibody mediated rejection and cardiac allograft vasculopathy. The molecular expression test score showed gradual increase and QTc-interval showed gradual prolongation with the gradual decline in graft function. This paper exemplifies that in patients presenting with unexplained graft dysfunction, GEP test score and QTc-interval correlate with the changes in the graft function.
Full-text · Article · Jun 2010 · Cardiology Research and Practice
[Show abstract][Hide abstract] ABSTRACT: Accurate assessment of left ventricular hypertrophy (LVH) and ventricular geometry is important, especially in patients with heart failure (HF). The aim of this study was to compare the assessment of ventricular size and geometry by 2D and 3D echocardiography in normotensive controls and among HF patients with a normal and a reduced ejection fraction.
One hundred eleven patients, including 42 normotensive patients without cardiac disease, 41 hypertensive patients with HF and a normal ejection fraction (HFNEF), and 28 patients with HF and a low ejection fraction (HFLEF), underwent 2DE and freehand 3DE. The differences between 2DE and 3DE derived LVM were evaluated by use of a Bland-Altman plot. Differences in classification of geometric types among the cohort between 2DE and 3DE were determined.
Two-dimensional echocardiography overestimated ventricular mass compared to 3D echocardiography (3DE) among normal (166 +/- 36 vs. 145 +/- 20 gm, P = 0.002), HFNEF (258 +/- 108 vs. 175 +/- 47gm, P < 0.001), and HFLEF (444 +/- 136 vs. 259 +/- 77 gm, P < 0.001) patients. The overestimation of mass by 2DE increased in patients with larger ventricular size. The use of 3DE to assess ventricular geometry resulted in reclassification of ventricular geometric patterns in 76% of patients with HFNEF and in 21% of patients with HFLEF.
2DE overestimates ventricular mass when compared to 3DE among patients with heart failure with both normal and low ejection fractions and leads to significant misclassification of ventricular geometry in many heart failure patients.
No preview · Article · Mar 2010 · Echocardiography
[Show abstract][Hide abstract] ABSTRACT: Anemia is a significant co-morbidity in patients with heart failure (HF) irrespective of the ejection fraction and is routinely quantified by hemoglobin concentration. Hemodilution as a cause of anemia has been described in systolic HF. The aim of this study was to further investigate the effects of plasma volume in patients with HF by (1) assessing the prevalence of dilutional anemia in patients with anemia and preserved ejection fractions and (2) exploring the relation between hemoglobin and red cell volume in these patients. Forty-six patients with anemia (as determined by standard hemoglobin measurement), 22 with HF and low ejection fractions (HFLEF) and 24 with HF and preserved ejection fractions (HFPEF), all underwent plasma volume measurement with iodine-131-labeled albumin. Hemoglobin values did not differ between subjects with HFLEF and those with HFPEF (10.8 +/- 1.0 vs 11.0 +/- 1.0 g/dl, p = 0.55), but a red cell deficit was found in 88% of patients with HFPEF compared with 59% of those with HFLEF (p = 0.04). This was the result of a higher prevalence of an expansion of plasma volume in patients with HFLEF (100%) compared with those with HFPEF (71%). Among all patients, no correlation was found between hemoglobin and red cell volume (r = 0.09, p = 0.54), but a correlation did exist in patients with normal blood volumes (r = 0.55, p = 0.02). In conclusion, dilutional anemia caused by an expansion in plasma volume without a red cell deficit occurs more commonly in patients with HFLEF than those with HFPEF, and hemoglobin does not correlate with red cell volume in patients with anemia and HF.
Preview · Article · Nov 2008 · The American journal of cardiology