Left Atrial Mechanics and Diastolic Function Among People Living With Human Immunodeficiency Virus (from the Veterans Aging Cohort Study)

Abstract

Human immunodeficiency virus (HIV) infection is associated with subclinical cardiomyopathy, diastolic dysfunction, and increased risk of cardiovascular death. However, the relationship between left atrial (LA) mechanics and left ventricular (LV) diastolic function has not been evaluated in people living with HIV (PLWH) relative to HIV-uninfected (HIV-) controls. This is a multicenter, cross-sectional cohort analysis using the HIV Cardiovascular Disease substudy of the Veterans Aging Cohort Study database, which aimed to examine a cohort of PLWH and HIV- veterans without known cardiovascular disease. A total of 277 subjects (180 PLWH, 97 HIV-) with echocardiograms were identified. LV and LA phasic strain were derived and diastolic function was evaluated. Relationship between LA strain, LV strain, and the degree of diastolic dysfunction were assessed using analysis of variance and ordinal logistic regression with propensity weighting. In the PLWH cohort, 91.7% were on antiretroviral therapy and 86.1% had HIV viral loads <500 copies/ml. The mean (± SD) duration of infection was 9.7 ± 4.9 years. Relative to HIV- veterans, PLWH did not differ in LA mechanics and proportion of diastolic dysfunction (p = 0.31). Using logistic regression with propensity weighting, we found no association between HIV status and degree of diastolic dysfunction. In both cohorts, LA reservoir strain and LA conduit strain were inversely and independently associated with the degree of diastolic dysfunction. Compared with HIV- veterans, PLWH who are primarily virally suppressed and antiretroviral-treated did not differ in LA strain or LV diastolic dysfunction. If confirmed in other cohorts, HIV viral suppression may curtail adverse alterations in cardiac structure and function.

Figure 1.

Representative 2D transthoracic echocardiogram and illustrative left atrial strain curve. The left panel is a transthoracic echocardiographic image in the apical 4-chamber view at ventricular end-systole. The left atrium (LA) is segmented for strain analysis. The right panel is a typical LA strain curve for one cardiac cycle. Reservoir strain is the strain value at LV end systole. Contractile strain is the change in strain between left atrial contraction at late LV diastole and the beginning of LV systole. Reference point is set to the end of LV diastole (R-R gating). LA, left atrium; LV, left ventricle; RA, right atrium; RV, right ventricle.

Figure 2:

Comparison of left atrial (LA) strain and markers of diastolic dysfunction in HIV- and people living with HIV (PWH). Relationship between number of markers of diastolic dysfunction and LA reservoir strain (A) and strain rate (B), LA conduit strain (C) and strain rate (D), LA contractile strain (E) and strain rate (F). Strain and strain rate are stratified by HIV status (HIV- = red, PWH = blue). The upper and lower edges of the box plot reflect the 75^th and 25^th percentiles and the midline reflects the median. The whiskers of the box plot represent the maximum value below the upper limit and minimum value above the lower limit, respectively. The upper limit is defined as 1.5(IQR) above the 75^th percentile. The lower limit is defined as 1.5(IQR) below the 25^th percentile. Outliers that are greater than ± 1.5(IQR) are indicated by markers. P values represent two-sided ANOVA for the PWH cohort. IQR, inter-quartile range