Effects of persisting myocardial sinusoids on left ventricular performance in pulmonary atresia with intact ventricular septum

The effects of persisting right ventricular myocardial sinusoids on left ventricular global and regional function were studied in 13 patients with pulmonary atresia and intact ventricular septum. Persisting myocardial sinusoids allow the inflow of undersaturated blood into the coronary circulation with subsequent myocardial ischaemia. 7 patients had myocardial sinusoids (group 1). 6 patients had normal coronary perfusion (group 2) The measures of global left ventricular function (ejection fraction, left ventricular enddiastolic volume, left ventricular enddiastolic pressure and shape index) showed no differences between the groups. All patients in group 1 showed disturbances of regional wall motion (P less than or equal to 0.005). There was a high degree of coincidence between the disturbances of regional wall motion and the topography of myocardial perfusion from persisting myocardial sinusoids. In group 1 apical hypokinesia was a regular finding, reflected by a significantly reduced shortening of the left ventricular long axis (P less than or equal to 0.01). As all of these patients had communications between the myocardial sinusoids and the left anterior descending coronary artery, this probably resulted from apical left ventricular ischaemia.