Effect of Septal Ablation on Regional Diastolic Dysfunction and Diastolic Asynchrony in Patients with Hypertrophic Obstructive Cardiomyopathy: A Follow-Up Study Using Speckle Tracking Echocardiography

Background Percutaneous transluminal septal myocardial ablation (PTSMA) is an alternative therapy for patients with hypertrophic obstructive cardiomyopathy (HOCM) that results in sustained improvement in the global diastolic dysfunction. Regional diastolic abnormalities and diastolic asynchrony are very common and closely related to global diastolic dysfunction. The aim of this study was to examine the effect of PTSMA on regional diastolic dysfunction and diastolic asynchrony in HOCM patients using speckle tracking echocardiography. Methods Strain rate curves were obtained for 18 different segments of the left ventricular (LV) myocardium in 30 HOCM patients 24hours before and 1year after PTSMA. The peak strain rate during the isovolumic relaxation period (SRIVR), the peak early diastolic strain rate (SRE), and the time from the onset of the QRS-wave to SRE (TSRE) were measured for each segment. The left atrial volume indexed to the body surface area (LAVI) was measured as a global diastolic index. Results At 1year after PTSMA, there was significant improvement of the global SRIVR (0.14 +/- 0.060.22 +/- 0.07%/sec, P<0.001) and SRE (0.67 +/- 0.240.82 +/- 0.23%/sec, P=0.001). The coefficient of variation in TSRE (CVTSRE) decreased significantly. The changes in the regional myocardial diastolic deformation and CVTSRE correlated well with the reduction in the LAVI. Conclusions Percutaneous transluminal septal myocardial ablation has a favorable effect on regional diastolic abnormalities and diastolic asynchrony, which may partly account for the persistent improvement in global LV diastolic function in HOCM patients after PTSMA. (Echocardiography 2013; 30: 564-571)