Left Ventricular Dysfunction Following the Ross-Konno Reconstruction is Independent of the Operation

The Ross-Konno (RK) operation is a well-established surgical treatment for combined left ventricular outflow tract obstruction and aortic valve pathology in children. Prior study has demonstrated that mechanical and electrical dyssynchrony exist post-RK compared to normal controls. The purpose of this study was to evaluate myocardial function pre- and post-RK as defined by echocardiography. Patients undergoing the RK operation (n = 13; median age: 1.3 years; range: 0.5-13.3 years) were evaluated by echocardiography at defined timepoints: pre-RK, post-RK, 1-year post-RK, and 2 years post-RK. Defined parameters of left ventricular performance were analyzed: systolic mechanical dyssynchrony (M-Dys), global left ventricular circumferential strain (GCS), and diastolic relaxation fraction (DRF). Patients with post-operative atrioventricular block (n = 6) were analyzed separately. No pre- versus post-RK differences existed in M-Dys, GCS, or DRF in patients both with and without post-RK atrioventricular block. Further, 1- and 2-year follow-up post-RK demonstrated significant heterogeneity in evaluated parameters of function with no pre- and post-RK differences in M-Dys, GCS, or DRF. Mechanical dyssynchrony exists post-RK reconstruction in both short- and long-term follow-up yet these echocardiographic parameters of ventricular performance are independent of the RK operation. Further study is, therefore, warranted to define causal relationships for observed short- and long-term ventricular dysfunction post-RK as the findings of the present study suggest a deleterious mechanism apart from the technical RK reconstruction.