Petretta M, Bonaduce D, Cuocolo A, Morgano G, Nicolai E, Pulcino A, Bianchi V, Salvatore M
Institute of Internal Medicine, University of Naples Federico II, Italy.
Coron Artery Dis. 1993 Jul;4(7):637-44. doi: 10.1097/00019501-199307000-00008.
This study evaluates the incremental prognostic value of qualitative thallium-201 imaging and coronary angiography in patients with suspected or known coronary artery disease.
Within 1 month, 150 patients underwent diagnostic symptom-limited ECG stress test, thallium imaging, and coronary angiography. The incremental power of sequentially performed tests was evaluated by the overall likelihood ratio statistic.
At 3-year follow-up, 16 patients had died from a cardiac cause, 12 had suffered a nonfatal myocardial infarction, and 34 had undergone revascularization procedures more than 60 days after testing. Considering hard events, thallium imaging did not improve the prognostic information provided by clinical exercise stress test data, while coronary angiography increased the predictive power of the combined, exercise stress test, and scintigraphic data (P < 0.001). Moreover, when thallium results were added to clinical, exercise, and coronary angiographic data, the predictive power was unchanged. When the analysis was repeated including the occurrence of late revascularization procedures, each test showed additional prognostic information to that obtained by the other combined tests (P < 0.001).
This study demonstrates that in patients with a symptom-limited ECG stress test, coronary angiography adds prognostic information to combined clinical, exercise ECG, and thallium imaging data. The incremental prognostic value of qualitative thallium imaging is demonstrable only when late revascularization procedures are included as events.
