Impact of Transcatheter Intervention on Myocardial Deformation in Patients with Coarctation of the Aorta.

Myocardial deformation measured by speckle tracking echocardiography can detect subtle abnormalities of left ventricular function before an obvious abnormality in traditional echocardiographic parameters such as ejection fraction is seen. We hypothesized that patients with coarctation of the aorta (CoA) may have impaired myocardial deformation that may persist even after successful transcatheter intervention. This is a retrospective study to assess the myocardial deformation in patients undergoing transcatheter intervention of CoA. The data were compared with age-matched normal controls. Echocardiographic parameters were obtained before, immediately and at median 6 months (range 3-8 months) after transcatheter intervention. Myocardial deformation indices were obtained off-line using Tomtec 2D Cardiac Performance Analysis Software. Repeated measure ANOVA was used to compare the indices between three time points. Independent sample t test or Chi-square test was used to compare data between groups. Twenty-four patients (age 13.5 ± 7.7 years) underwent successful transcatheter CoA intervention (stent 19, balloon angioplasty five) improving CoA peak gradient in the catheterization laboratory from 27.1 ± 11.3 to 4.5 ± 3.0 mmHg (p < 0.001). To compare with normal controls (n = 25, age 14.5 ± 1.9 years), fraction shortening was significantly higher in pre-intervention CoA patients (40.4 ± 7.1 vs. 33.8 ± 2.4 %, p < 0.001). In contrast, CoA patients had significantly abnormal left ventricular longitudinal strain compared to normal controls (-14.9 ± 2.6 vs. -20.5 ± 1.8 %, p < 0.001). In CoA patients, left ventricular longitudinal strain improved immediately and 3-8 months after intervention (-18.0 ± 2.9 and -17.6 ± 2.9 %, p < 0.007) but continued to be abnormal compared to normal controls. Patients with CoA had impaired myocardial deformation compared to normal controls. Myocardial mechanics improved but did not normalize even after successful transcatheter intervention on CoA in the short term.