Prevalence, Associated Factors, and Echocardiographic Estimation of Left Atrial Hypertension in Patients With Atrial Fibrillation

Background: Elevated left atrial (LA) pressure predisposes individuals to the initiation and persistence of atrial fibrillation (AF), and LA hypertension is associated with AF recurrence after catheter ablation (CA). However, the exact frequency and factors associated with LA hypertension are unknown, and its noninvasive estimation is challenging. This study aimed to investigate the prevalence and determinants of LA hypertension in patients with AF who underwent first CA. Methods and Results: We examined 183 patients with AF who underwent conventional and speckle-tracking echocardiography before CA to assess LA size, reservoir strain, and stiffness. Direct LA pressure was measured at the time of CA, and LA hypertension was defined as mean LA pressure >15mmHg. Thirty-three (18.0%) patients exhibited LA hypertension. Patients with LA hypertension had a significantly larger LA volume index (40.2 [28.4-52.1] versus 34.1 [26.9-42.4] mL/m(2), P=0.025), reduced LA reservoir strain (15.1 [10.4-21.7] versus 22.7 [14.4-32.3] %, P=0.002) and increased LA stiffness (0.69 [0.34-0.99] versus 0.36 [0.24-0.54], P<0.001). Multivariable analyses showed that waist circumference, C-reactive protein level, LA reservoir strain, and LA stiffness were independently associated with LA hypertension (all P<0.05), while LA volume and E/e' ratio were not. Among echocardiographic parameters, receiver operating characteristic curve analysis identified LA stiffness as the best predictor of LA hypertension. Conclusions: Approximately 20% of patients with AF who underwent CA had LA hypertension. Central obesity and inflammation might be involved in the pathophysiological mechanisms of LA hypertension, and echocardiography-derived LA stiffness may have clinical utility for the detection of LA hypertension before CA.