Determinants of left atrioventricular coupling index: The Multi-Ethnic Study of Atherosclerosis (MESA)

Theo Pezel, Bharath Ambale Venkatesh, Henrique Doria De Vasconcellos, Yoko Kato, Wendy S. Post, Colin O. Wu, Susan R. Heckbert, David A. Bluemke, Alain Cohen-Solal, Damien Logeart, Patrick Henry, João A.C. Lima

Recent studies have described a novel left atrioventricular coupling index (LACI), which had a better prognostic value in predicting cardiovascular events than individual left atrial (LA) or left ventricular (LV) variables.

To identify determinants of LACI and its 10-year annual change (LACI), measured by cardiac magnetic resonance (CMR), and to better understand the variables governing this left atrioventricular coupling.

In the Multi-Ethnic Study of Atherosclerosis, 2112 study participants, free from cardiovascular disease at baseline, had LACI assessed by CMR imaging at baseline (LACIBaseline; 2000—2002) and 10 years later (2010—2012). The LACI was defined as the ratio of LA to LV end-diastolic volumes. Linear regression analyses were performed to identify independent determinants of LACIBaseline and LACI.

In the 2112 participants (mean age 58.8 ± 9.1 years; 46.6% male), after adjustment for all covariates, age was independently associated with LACIBaseline (R2 = 0.10, slope = 0.16) and LACI (R2 = 0.15, slope = 0.008; both P < 0.001). African Americans had the highest LACIBaseline value (18.0 ± 7.7%). Although there was no difference in LACIBaseline between women and men (P = 0.19), LACI was higher in women (1.0 ± 1.1 vs 0.8 ± 1.1%/year; P < 0.001). Diabetes and higher body mass index (BMI) were independently associated with LACIBaseline (both P < 0.001). LACIBaseline was independently associated with LV myocardial fibrosis markers (native T1: R2 = 0.11, slope = 0.09 [P = 0.038]; extracellular volume: R2 = 0.08, slope = 0.28 [P = 0.035]) and N-terminal prohormone of B-type natriuretic peptide (NT-proBNP) concentration (R2 = 0.10, slope = —1.11; P < 0.001), but was not associated with interleukin 6 or high-sensitivity C-reactive protein.

Age, sex, ethnicity, diabetes and BMI were independent determinants of LACI. LACI was independently associated with myocardial fibrosis markers and NT-proBNP concentration.