Associations of Left Atrial Volume Index to Left Ventricular Ejection Fraction Ratio with Clinical Outcomes in Transthyretin Cardiac Amyloidosis.

BACKGROUND

Transthyretin amyloid cardiomyopathy (ATTR-CM) affects all cardiac chambers to cause left ventricular (LV) deformation as well as left atrial (LA) remodeling and functional impairment. We investigated the associations of the LA volume index (LAVI):LV ejection fraction (LVEF) ratio with the increased risk of death, heart transplant, or LV assist device implantation (LVAD) in patients with ATTR-CM.

METHODS

This was a retrospective cohort study involving 69 heart failure (HF) patients with ATTR-CM at an academic medical center between 1 November 2008 and 31 March 2024. ATTR-CM was diagnosed using a technetium-diphosphonate/pyrophosphate scan or an endomyocardial biopsy. The LAVI and LVEF were measured by echocardiography. Cox proportional hazards models were used for the analysis.

RESULTS

The mean (SD) age of the participants was 77.5 (9.3) years. Over a median (IQR) follow-up period of 1.96 (0.67-2.82) years, we observed 24 composite events that included twenty-two deaths, two heart transplants, and two LVAD implantations (who subsequently died). In multivariable-adjusted analyses that accounted for age and the glomerular filtration rate, a one-unit increase in the LAVI:LVEF ratio was associated with a doubling of the risk (HR, 95% CI: 2.06, 1.11-3.82) of experiencing the composite outcome.

CONCLUSIONS

A one-unit increase in the LAVI:LVEF ratio was associated with an increased risk of death, heart transplant, or LVAD implantation in patients with ATTR-CM.