September 10, 2007Open Access

Atrial myocardial deformation properties are temporarily reduced after cardioversion for atrial fibrillation and correlate well with left atrial appendage function

Q: What is the clinical evidence from this study?

Study design: Cohort. Population: chronic atrial fibrillation (n=22). Intervention: Cardioversion vs. Before cardioversion. Primary outcome: Correlation between left atrial systolic strain and left atrial appendage emptying velocity (LAAEV) (r = 0.73, p=0.007).

Key Result

After successful cardioversion for atrial fibrillation, left atrial systolic strain correlated well with left atrial appendage emptying velocity (r = 0.73, P = 0.007).

Study Design

Type

Cohort (n=22)

PICO

Population

22 consecutive patients with chronic atrial fibrillation for 3 to 12 months undergoing successful cardioversion, followed for 10 days.

Exposure / Comparator

Cardioversion vs Before cardioversion

Primary Outcome

Correlation between left atrial systolic strain and left atrial appendage emptying velocity (LAAEV) — r = 0.73, p=0.007

Main Result

Effect estimate: r = 0.73

p-value: p=0.007

Abstract

AIM: This study was conducted to evaluate whether left atrial strain and strain rate correlate well with transesophageal parameters of stunning after atrial fibrillation. METHODS AND RESULTS: Twenty-two consecutive patients with chronic atrial fibrillation >/=3 months and <1 year were enrolled in the study. Transthoracic (TTE) and transesophageal (TEE) echocardiography with color Doppler myocardial imaging were performed before, 1 day after and 10 days after successful cardioversion. Left atrial transthoracic strain (S) and strain rate (SR) from lateral, inferior and anterior atrial walls, left atrial appendage tissue velocities, strain and strain rate values were measured with offline analysis. Left atrial appendage emptying (LAAEV) and filling (LAAFV) velocities were obtained from transesophageal echocardiography. Left atrial transthoracic, and left atrial appendage strain and strain rates were significantly lower following 1 day after cardioversion (TTE S/SR, 5.0 +/- 2.8%/2.3 +/- 1.0; TEE (septal) S/SR, 7.6 +/- 3.6%/1.6 +/- 0.7). There was a good correlation between these parameters and LAAEV (LA systolic strain and LAAEV, r = 0.73, P = 0.007). Left atrial and LAA strain and strain rate values improved over time, and correlated well with LAAEV, measured 10 days after cardioversion. CONCLUSIONS: Transthoracic atrial and TEE LAA strain and strain rate, which are quantitative measures of atrial function, are reduced after cardioversion, and recover subsequently. The good correlation between LAA function and TTE strain and strain rate suggests that TTE atrial parameters may help determine duration of anticoagulation.