Impact of myocardial perfusion gated-SPECT on the decision to perform coronary angiography in patients with left ventricular dysfunction of ischemic origin

Objectives

The aim of this study was to analyze how the myocardial perfusion gated-SPECT (Single Photon Emission Computed Tomography) influences the practice of a coronary angiography in patients with ischemic cardiomyopathy (IM).

Patients and methods

A total of 120 consecutive patients (mean age: 64.9 ± 11.5 years, 25 female) with IM (left ventricular ejection fraction ≤40%) and without previous coronary angiography were evaluated by myocardial perfusion gated-SPECT (96 stress-rest and 24 only at rest). The ventricular ejection fraction (EF) was obtained at rest by gated-SPECT in all patients. The ischemic origin of the systolic dysfunction was established by means of coronary angiography in 64 patients and by previous myocardial infarction in the rest. Gated-SPECT results of these 64 patients were compared with those of 56 patients in whom coronary angiography had not been indicated.

Result

Scintigraphic myocardial ischemia (HR: 5.2; CI 95%: 2.68 to 10.35) in patients who were able to perform the stress-rest test) and who had severely impaired EF (<30%) (HR: 0.9; CI 95%: 0.89 to 0.99) were the best independent predictors of coronary angiography. On the contrary, scintigraphic criteria of viability were not a determinant, from the statistical point of view, of coronary angiography in this series.

Conclusions

In patients with IM, demonstration of ischemia and severe reduction of the EF, but not detection of viable myocardium, prompted the performance of coronary angiography.