Atrial Myocardial Deformation Properties Predict Maintenance of Sinus Rhythm After External Cardioversion of Recent-Onset Lone Atrial Fibrillation

BACKGROUND: Accurate echocardiographic parameters to predict maintenance of sinus rhythm in patients with atrial fibrillation (AF) are poorly defined. This study was conducted to assess the atrial myocardial properties during AF through myocardial velocity, strain rate, and strain and to compare their prognostic value in maintaining sinus rhythm in patients with lone AF with standard transthoracic (TTE) and transesophageal echocardiography (TEE). METHODS AND RESULTS: Sixty-five consecutive patients with lone AF for < or =3 months underwent TTE, TEE, and myocardial velocity and strain and strain rate imaging examinations before successful external cardioversion. Maintenance of sinus rhythm was assessed during a 9-month follow-up. Atrial myocardial velocity, strain, and strain rate values in AF patients were compared with those of age- and sex-matched referents. Moreover, clinical and echocardiographic parameters of patients with maintenance of sinus rhythm (MSR patients) over the 9-month follow-up period (n=25) were compared with those from patients with AF recurrence (AFR patients; n=40). Atrial myocardial properties assessed by myocardial velocity, strain rate, and strain were significantly reduced (P<0.0001) in patients (velocity, 3.2+/-1.4 cm/s; strain, 23.3+/-19%; strain rate, 2+/-0.9 seconds(-1)) compared with referents (velocity, 5.7+/-1.3 cm/s; strain, 92+/-26%; strain rate, 4.2+/-1.8 seconds(-1)). The individual predictors of sinus rhythm maintenance were atrial appendage flow velocity (MSR patients, 39+/-12 cm/s; AFR patients, 32+/-15 cm/s; P<0.01) assessed by TEE and atrial strain (MSR patients, 33+/-27%; AFR patients, 17+/-9%; P=0.0007) and strain rate (MSR patients, 2.7+/-1 seconds(-1); AFR patients, 1.6+/-0.6 seconds(-1); P<0.0001) peak systolic values. Atrial strain (P<0.0001; coefficient, 0.015; SE, 0.003) and strain rate (P<0.0001; coefficient, 0.372; SE, 0.075) parameters alone were confirmed as independent predictors of sinus rhythm maintenance by multivariable analysis. CONCLUSIONS: Patients with higher atrial strain and strain rate appear to have a greater likelihood of staying in sinus rhythm. If the current data are verified in future studies, then additional pharmacological therapy and maintenance of anticoagulants for a longer period may need to be considered in those with lower atrial strain and strain rate measurements.