Would coronary collaterals to the infarct-related artery serve as a marker of viability in patients with prior myocardial infarction? A study with trimetazidine-(99m)Tc-sestamibi imaging

Abstract

Background: Visualization of collateral circulation to the infarct-related artery on coronary angiography was suggested to predict viability in the infarct zone as demonstrated by dobutamine stress echocardiography.

Methods and materials: We enrolled 30 consecutive patients referred from our catheterization labs with prior Q-wave myocardial infarction at least 6 months before study enrollment. Patients were classified according to the presence of collaterals to the infarct-related artery into two groups: collateral group with Rentrop Grade 1-3 collaterals, and noncollateral group with Rentrop Grade 0 collaterals. Patients underwent resting (99m)Tc-sestamibi imaging study with the administration of trimetazidine, using the standard technique, within 4 days of coronary angiography. Viability in a specific territory was defined when at least 50% of its individual segments were classified as viable.

Results: The visualization of collaterals by coronary angiography was able to predict viability in the territory supplied by the infarct-related artery with a sensitivity of 88.2%; specificity of 53.8%; positive and negative predictive values of 71.4% and 77.8%, respectively; and a diagnostic accuracy of 73.3%. The presence of viability increased progressively, in a statistically significant manner, from Rentrop Grade 0 to Grade 1 and Grade 2 [2 (22.2%), 5 (50%), 10 (91%), respectively, P = .04].

Conclusions: Visualization of coronary collaterals to the infarct-related artery by coronary angiography may predict with a high sensitivity but a low specificity the presence of viability in the territory supplied by that artery.