To evaluate the influence of two techniques of myocardial protection on septal wall motion (SWM) and left ventricular ejection fraction, 21 patients with a normal SWM underwent surgery using either conventional antegrade cardioplegia (group I, n = 9) or combined antegrade/retrograde cardioplegia (group II, n = 12). The patients were assessed pre- and postoperatively by radionuclide ventriculography. A resting thallium-201 study was performed in patients (n = 6) with a postoperatively abnormal SWM: in 2 of 9 (22%) in group I and in 4 of 12 (33%) in group II (p = NS). The left ventricular ejection fraction was similar in both groups before surgery (57 ± 3% in group I vs. 57 ± 8% in group II; p = NS) and did not change significantly after surgery. All 6 patients with an abnormal SWM had a normal septal thallium-201 uptake. Thus, (1) an abnormal SWM after cardiac surgery is common; (2) it is not due to perioperative ischemia or infarction, and (3) neither the incidence of an abnormal SWM not the global left ventricular function is influenced by the addition of retrograde cardioplegia during open heart surgery.