Myocardial performance after successful intervention for native aortic coarctation

Abstract

Coarctation of the aorta is associated with increased risk for hypertension in adulthood, despite successful repair. The intrinsic mechanisms underscoring hypertension and left ventricular performance in these patients, however, remains to be determined. Our objective was to evaluate left ventricular performance by means of echocardiographic and biochemical parameters at midterm follow-up in normotensive children who have had undergone successful surgical or catheter interventional treatment of coarctation with a residual gradient of less than 20 mmHg at rest. We studied prospectively 14 patients with native aortic coarctation who underwent surgery or balloon angioplasty, the cohort made up of equal numbers of boys and girls, and having a mean age of 8.5 plus or minus 4 years. We also studied 30 age-matched healthy subjects, measuring mitral inflow pulsed wave signals, isovolumic relaxation and contraction times, myocardial performance index parameters, and levels of B-type natriuretic peptide and endothelin-1 in both groups. We found no differences in systolic blood pressure at rest between the patients and their controls. The ventricular septal diastolic dimensions, left ventricular posterior wall dimensions, mitral valve E wave, deceleration time, isovolumic relaxation time, isovolumic contraction time and myocardial performance index were all significantly increased in the patients. Levels of plasma B-type natriuretic peptide and endothelin-1 were also significantly higher in the patients when compared to the control group. We conclude that aortic coarctation is a chronic disease characterized by persistency of myocardial and vascular alterations. The elevated levels of plasma b-type natriuretic peptide and endothelin-1 may be indicative of late onset hypertension after successful treatment of native coarctation in early childhood.