Left Ventricular Function Assessment of Patients with Postoperative Ventricular Septal Defect Closure by Longitudinal Strain on Two-Dimensional Echocardiography 1 Year after Surgery

Abstract

Background: Patients with large perimembranous ventricular septal defects (pm-VSDs) undergo surgical repair with prosthetic material during infancy. However, the effect of the presence of akinetic patch in the ventricular septum on the left ventricular (LV) mechanical synchrony and ventricular function has not been studied. In our study, we assessed LV function in postoperative pm-VSD closure patients on two-dimensional (2D) echocardiography (echo) after 1 year of surgery using biplane Simspon's method, fractional shortening (FS), and global longitudinal strain (GLS) to assess the regional strain pattern. Methods: This was a a single-institution observational study. Patients following up 1 year after surgical ventricular septal defect closure at our institute were enrolled. On follow-up, detailed 2D echo was done with special emphasis on left atrial size, LV size (by M-mode), and presence of any residual shunt. LV function was assessed using biplane Simpson's method and longitudinal strain on 2D echo. GLS was measured in three standard apical views. Results: Of the 121 patients enrolled, 101 patients fulfilling the inclusion and exclusion criteria were analyzed. Of these 101 patients, 75.2% were males. The median age at follow-up after surgery was 3.67 ± 2.7 years. About 92.1% of patients did not have residual VSD lesion. No patient had pulmonary arterial hypertension. All except one patient had normal ventricular function. Patients with ventricular dysfunction had LV ejection fraction (LVEF) of 47%, GLS –17.4%, and FS −20.5%. The mean values of FS, LVEF, and GLS were 32.0 ± 5.28%, 62.2% ± 4.2%, and −26.53 ± 2.93%, respectively, in pm-VSD closure patients. Regional strain pattern analysis showed significantly lower strain values in basal anteroseptal segment with a mean of −21.4 ± 2.7%. FS and GLS were noted to have significant correlation with each other (P = 0.01) and LVEF by biplane Simpson's method and GLS had significant correlation with each other (P = 0.0001). Conclusions: GLS has strong correlation with LVEF by Simson's method and FS. Basal anteroseptal segment in pm-VSD patients had significantly lower strain values compared to other segments. There is no significant correlation between age at surgery and GLS in pm-VSD closure patients who were operated within 1 year of age. The type of VSD closure does not have significant influence on GLS.