In HCM, LAVI and resting LVOT gradient were each independently associated with incident AF, and neither remained significant when modeled together, suggesting LAVI may serve as a practical echocardiographic marker to refine AF risk assessment.
Left atrial volume index (LAVI) was independently associated with incident atrial fibrillation in hypertrophic cardiomyopathy after adjustment for age, sex, and hypertension.
AF risk increased significantly across LAVI tertiles.
Resting LVOT gradient was independently associated with incident AF after adjustment for age, sex, and hypertension.
In a head-to-head model including both LAVI and resting LVOT gradient simultaneously, neither association remained statistically significant.
Among 777 HCM patients identified by ICD-10 code I42.1, 547 were eligible after excluding those with pre-existing AF or atrial flutter, and 60 developed incident AF during follow-up.
This research examined whether two measurements obtained from heart ultrasound (echocardiography) — the size of the left atrium (measured as left atrial volume index, or LAVI) and the degree of obstruction to blood flow leaving the heart (left ventricular outflow tract gradient, or LVOT gradient) — could predict which patients with hypertrophic cardiomyopathy (HCM) would go on to develop atrial fibrillation (AF), an irregular heart rhythm. The study followed 547 HCM patients without prior AF for a median of about 2.3 years, during which 60 patients developed AF. Both a larger left atrial size and a higher LVOT gradient were each independently linked to greater AF risk when analyzed separately, but when both measurements were considered together in the same statistical model, neither remained a statistically significant predictor on its own. The finding that both markers carry overlapping predictive information suggests they may reflect related aspects of the same underlying disease process in HCM — namely, how much pressure and stress is being placed on the heart's chambers. LAVI, as a measure of left atrial enlargement, is straightforwardly obtained during routine echocardiography and has previously been linked to AF risk in other heart conditions. This study adds evidence that in HCM specifically, larger left atrial size is associated with a 27% increased risk of AF for every 10 mL/m2 increase in LAVI. This research suggests that routinely measuring left atrial size in HCM patients could help clinicians identify those at higher risk of developing AF, potentially allowing for closer monitoring or earlier intervention. Because LAVI is already part of standard echocardiographic assessment, incorporating it into AF risk stratification for HCM patients would not require additional testing. However, the study was retrospective, LAVI data were only available for a subset of patients, and the findings would benefit from validation in larger prospective studies before being widely applied in clinical practice.
Salman O, Pradeep A, Purkayastha S, Parikh V, Stahl E. (2026). Left Atrial Volume Index, Left Ventricular Outflow Tract Gradient, and Incident Atrial Fibrillation in Hypertrophic Cardiomyopathy.. Echocardiography (Mount Kisco, N.Y.). https://doi.org/10.1111/echo.70624