Nuclear ventriculography (MUGA) was performed in 22 patients at rest and during the
stress of right atrial pacing 6 to 8 days after coronary artery bypass surgery. In
7 patients the MUGA-atrial pacing test was positive for ischemia with chest pain,
electrocardiographic ST depression and/or a decrease in global left ventricular ejection
fraction of > 10 %. All 7 patients subsequently developed angina pectoris with a positive
treadmill test (performed at a median time of 14 months after operation) . In 15 patients,
the early postoperative MUGA-atrial pacing test was negative. In this group, 3 patients
subsequently developed angina pectoris with a positive treadmill test in one . The
sensitivity of the ‘one week’ early postoperative MUGA-atrial pacing in the identification
of patients with residual myocardial ischemia was high (88 % for positive GXT, p <
0.0001; 70 % for chest pain, p < 0.005) with 100 % specificity. The early postoperative
MUGA scan was also useful in predicting later shortness of breath on exertion and
there was a significant correlation between the early resting ejection fraction and
the exercise capacity of the patient subsequently. The information obtained from an
early postoperative MUGA-atrial pacing study may have farreaching and important practical
application in selecting patients for early recatheterlzation, possible fibrinolysis
and/or possible cardiac reoperation.
Myocardial revascularization - Angina pectoris - Nuclear angiography - Stress testing
