Myocardial perfusion imaging and coronary angiography in patients with known or suspected stable angina pectoris

Introduction:. The patho-physiological cause of angina pectoris is myocardi al ischaemia,which can be objectified by myocardial perfusion imaging (MPI) Methodology: MPI was undertaken prior to coronary angiography (CAG) in 86 r andomly selected patients with known or suspected stable angina pectoris. Results: Among 78 adequately stressed patients;, MPI was normal in 28 (36%) and showed reversible and irreversible perfusion abnormalities in 30 (38%) and 20 patients (26%), respectively. Coronary angiograms were normal in 28 (36%) and revealed at least one greater than or equal to 50% stenosis in 5 0 patients (64%) (16 with single and 34 with multi vessel disease). Using a ngiography as a reference, the sensitivity and specificity of MFI in detect ing coronary artery disease was 88% and 93%, respectively. Discussion: MPI demonstrates regional hypoperfusion whereas CAG depicts ana tomical stenosis in epicardial arteries. Both modalities are potentially re levant in patients with stable angina pectoris. Tile functional significanc e of coronary artery lesions is, however, variable and MPI can demonstrate normal myocardial perfusion in the presence of moderate lesions. MPI exhibi ted a high sensitivity and specificity regarding significant lesions. More than one third of the subjects had a normal MPI and a normal CAG patients w ith stable angina pectoris and a normal MPI have a very low risk of cardiac events and do usually not require further invasive investigation or therap y. Reversible ischaemia and irreversible ischaemia with demonstration of vi able tissue call for coronary revascularisation.