Adiposity Is Associated with Gender-Specific Reductions in Left Ventricular Myocardial Perfusion during Dobutamine Stress.

BACKGROUND:Obesity and visceral adiposity are increasingly recognized risk factors for cardiovascular disease. Visceral fat may reduce myocardial perfusion by impairing vascular endothelial function. Women experience more anginal symptoms compared to men despite less severe coronary artery stenosis, as assessed by angiography. Women and men have different fat storage patterns which may account for the observed differences in cardiovascular disease. Therefore, our objective was to evaluate the relationship between visceral adipose tissue distributions and myocardial perfusion in men and women. METHODS:Visceral and subcutaneous fat distributions and myocardial perfusion were measured in 69 men and women without coronary artery disease using magnetic resonance imaging techniques. Myocardial perfusion index was quantified after first-pass perfusion with gadolinium contrast at peak dose dobutamine stress. RESULTS:We observed inverse relationships between female gender (r = -0.35, p = 0.003), pericardial fat (r = -0.36, p = 0.03), intraperitoneal fat (r = -0.37, p = 0.001), and retroperitoneal fat (r = -0.36, p = 0.002) and myocardial perfusion index. Visceral fat depots were not associated with reduced myocardial perfusion at peak dose dobutamine in men. However, in women, BMI (r = -0.33, p = 0.04), pericardial fat (r = -0.53, p = 0.02), subcutaneous fat (r = -0.39, p = 0.01) and intraperitoneal fat (r = -0.30, p = 0.05) were associated with reduced myocardial perfusion during dobutamine stress. CONCLUSIONS:Higher visceral fat volumes are associated with reduced left ventricular myocardial perfusion at peak dose dobutamine stress in women but not in men. These findings suggest that visceral fat may contribute to abnormal microcirculatory coronary artery perfusion syndromes, explaining why some women exhibit more anginal symptoms despite typically lower grade epicardial coronary artery stenoses than men

Measurement of myocardial perfusion index.

<p>(A) Segment from representative mid-ventricular slice during first-pass perfusion imaging during peak dose dobutamine stress. Red region of interest defines the middle of the left ventricle (LV) for measuring the slope of blood, and the green circle defines the middle interventricular septal myocardium which was used to measure the slope of myocardial perfusion. (B) The signal intensities (Y-axis) over time (X-axis) were plotted for blood (red) and LV myocardium (green). The upslope of LV blood and upslope of LV myocardium were plotted and used for determination of myocardial perfusion index (MPI).</p

Circulating T-Cell Subsets, Monocytes, and Natural Killer Cells in Peripartum Cardiomyopathy: Results From the Multicenter IPAC Study

•Immune cell subsets were examined in healthy postpartum and peripartum cardiomyopathy (PPCM) women.•In the early postpartum, PPCM women had lower NK and higher CD3+CD4–CD8–CD38+ T cell levels.•Levels largely normalized by 6 months postpartum. The aim of this work was to evaluate the hypothesis that the distribution of circulating immune cell subsets, or their activation state, is significantly different between peripartum cardiomyopathy (PPCM) and healthy postpartum (HP) women. PPCM is a major cause of maternal morbidity and mortality, and an immune-mediated etiology has been hypothesized. Cellular immunity, altered in pregnancy and the peripartum period, has been proposed to play a role in PPCM pathogenesis. The Investigation of Pregnancy-Associated Cardiomyopathy (IPAC) study enrolled 100 women presenting with a left ventricular ejection fraction of <0.45 within 2 months of delivery. Peripheral T-cell subsets, natural killer (NK) cells, and cellular activation markers were assessed by flow cytometry in PPCM women early (<6 wk), 2 months, and 6 months postpartum and compared with those of HP women and women with non–pregnancy-associated recent-onset cardiomyopathy (ROCM). Entry NK cell levels (CD3–CD56+CD16+; reported as % of CD3– cells) were significantly (P < .0003) reduced in PPCM (6.6 ± 4.9% of CD3– cells) compared to HP (11.9 ± 5%). Of T-cell subtypes, CD3+CD4–CD8–CD38+ cells differed significantly (P < .004) between PPCM (24.5 ± 12.5% of CD3+CD4–CD8– cells) and HP (12.5 ± 6.4%). PPCM patients demonstrated a rapid recovery of NK and CD3+CD4–CD8–CD38+ cell levels. However, black women had a delayed recovery of NK cells. A similar reduction of NK cells was observed in women with ROCM. Compared with HP control women, early postpartum PPCM women show significantly reduced NK cells, and higher CD3+CD4–CD8–CD38+ cells, which both normalize over time postpartum. The mechanistic role of NK cells and “double negative” (CD4–CD8–) T regulatory cells in PPCM requires further investigation

Alirocumab and Cardiovascular Outcomes after Acute Coronary Syndrome

BACKGROUN

Alirocumab and cardiovascular outcomes after acute coronary syndrome

BACKGROUN