Scintigraphic prediction of left ventricular functional recovery early after primary coronary angioplasty using single-injection quantitative electrocardiographic gated SPECT

Abstract

The clinical usefulness of characterizing reperfused myocardium by perfusion/thickening assessment using electrocardiographic gated single photon emission computed tomography (SPECT) has not been investigated. We evaluated whether single-injection gated SPECT with 99mTc tetrofosmin early after primary percutaneous coronary intervention (PCI) can predict left ventricular (LV) functional recovery.

Gated SPECT was performed 3 days after primary PCI in 45 patients with acute myocardial infarction and revascularized segments were classified into perfusion/thickening mismatched segments, matched normal and matched abnormal segments. Gated SPECT was repeated 3 months later to evaluate the changes in LV ejection fraction (ΔLVEF).

Among 332 revascularized segments, there were 83 mismatched segments, 163 matched abnormal segments and 86 matched normal segments. In all the patients, LVEF increased significantly from 3 days to 3 months after primary PCI (52±13 to 57±14%, P<0.0001). Patients were divided into two groups according to ΔLVEF: 24 patients with LV functional recovery (ΔLVEF ≥5%) and 21 patients without LV functional recovery. The number of mismatched segments in patients with LV functional recovery was significantly greater than that in patients without (2.7±1.7 vs. 0.8±1.4, P<0.0003) despite no differences in the number of matched abnormal and matched normal segments. There was a significant correlation between ΔLVEF and the number of mismatched segments (r=0.56, P<0.0001) and LVEF at 3 months after primary PCI was related to the number of matched abnormal segments (r=−0.78, P<0.0001).

Single-injection gated SPECT early after primary PCI can predict LV functional recovery.