Postoperative hemodynamic and electrophysiological evaluation of the Senning procedure

To determine efficacy of the Senning procedure for correction of transposition of the great arteries we performed detailed hemodynamic and electrophysiological studies in 6 consecutive children operated upon at 5-18 months of age. Cardiac catheterizations were performed 10-19 months following surgery. All patients were asymptomatic on no medication. Hemodynamic studies demonstrated no evidence of pulmonary venous obstruction, pulmonary hypertension, or left ventricular outflow tract obstruction. 1 patient had mild upper baffle limb obstruction. Angiography demonstrated tricuspid insufficiency in 2 patients and a small atrial level shunt in 1. Ambulatory electrocardiographic monitoring in 5 of 6 patients revealed multiple premature ventricular contractions in 1. Invasive electrophysiological studies for sinus node function were normal. Corrected sinus node recovery time was 36-348 ms while total sinoatrial conduction time, determined in 4 patients, ranged between 83 and 128 ms. At our institution the Senning procedure has a low incidence of residual hemodynamic or electrophysiological abnormalities. Detailed postoperative evaluation is necessary to determine extent of residual problems.