Patients with Right Bundle Branch Block (4)
Sixteen patients underwent coronary angiography within six months of the exercise radionuclide angiogram. Coronary angiography was performed using a standard percutaneous femoral or brachial cut-down approach. Multiple selective contrast injections were performed in the left and right coronary arteries. Caudal and cranial angulation were routinely employed. The degree of coronary artery stenosis was assessed visually in each of 23 different segments by two observers who usually were unaware of the radionuclide results. Significant coronary artery disease was established using the definitions of the Coronary Artery Surgery Study, ie, greater than or equal to 50 percent stenosis of the left main coronary artery and greater than or equal to 70 percent stenosis of the remaining coronary vessels were considered significant. canadian health and care mall
A radionuclide angiogram was considered positive for ischemia if there was (1) a decrease in left ventricular ejection fraction with exercise, or (2) the development of a new wall motion abnormality with exercise. Sensitivity and specificity were defined as follows: sensitivity = number of patients with positive exercise ECGs and positive radionuclide angiograms/total number of patients with positive radionuclide angiograms; specificity = number of patients with negative exercise ECGs and negative radionuclide angiograms/ total number of patients with negative radionuclide angiograms. The sensitivity and specificity were computed individually for the limb leads, \Wa, V4, V3, V, and V„ and for the exercise ECG beginning with leads Vs and V6 and then adding the limb leads, V4, V3, V, and V,. A receiver-operator curve was constructed by plotting sensitivity on the Y axis and 1-specificity on the X axis.