Abstract 18217: Left Ventricular Systolic Strain would be an Independent Predictor for Developing Atrial Fibrillation in Patients with Non-obstructive Hypertrophic Cardiomyopathy
Background: Hypertrophic cardiomyopathy (HCM) is associated with arrhythmias and cardiovascular death. Atrial fibrillation (AF) is considered a marker for death or/and decompensated heart failure in patients with HCM. Left ventricular (LV) strain derived from tissue Doppler ultrasound has been reported to be correlated with LV diastolic function. We hypothesized that left ventricular (LV) strain would predict development of AF in patients with HCM.
Methods: Retrospective observational studies were conducted with 67 consecutive patients with non-obstructive HCM, who were at sinus rhythm and without any treatment at their initial visit. Conventional echocardiography and TDI, which were obtained at their initial visit, were analyzed retrospectively. Mean values of LV systolic strain and strain rates obtained from 8 LV segments were calculated. In a subset of 42 patients, left and right heart pressures were recorded within a week from the echocardiograms.
Results: Mean observational period was 8.2 ± 3.9 years. Twenty-two patients (32.8%) developed chronic AF or paroxysmal AF lasted more than 24 hours at 5.2 ± 2.5 years from their initial visit, were assigned to group AF. The remaining 45 patients without AF episodes were assigned to group S. The absolute value of LV strain and LV end-systolic internal diameter were reduced, and LV ejection fraction was increased in group AF than those in group S (−20.2 ± 6.1 vs. -24.3 ± 6.9 %, p=0.02, 23.5 ± 2.3 vs. 26.1 ± 4.6 mm, p=0.02, 74.6 ± 7.3 vs. 66.5 ± 12.1 %, p=0.005). Other parameters including left atrial diameter were not significantly different between the groups. In a subgroup analysis of patients with pressure measurements, patients in group AF showed significantly higher LV end-diastolic pressure (LVEDP) than that in group S (19.0 ± 4.2 vs. 15.5 ± 5.3 mmHg, p=0.008,), and LV strain was correlated with LVEDP (r=0.54, p=0.0008). Multivariate analysis of echocardiographic parameters revealed that LV strain was the only factor independently associated with development of AF (odds ratio 0.6, 95% confidence interval 0.23–0.74).
Conclusions: Reduced LV strain at the initial clinical visit is highly associated with future development of AF, a risk factor for cardiovascular death in this population.
- © 2010 by American Heart Association, Inc.