Hypoperfused myocardium and systolic function in patients with AMI undergoing complete revascularization

Coronary revascularization is the standard treatment for acute myocardial infarction (AMI), while the restoration of epicardial flow is non-parallel to myocardial reperfusion. This study sought to investigate the dynamic of myocardial perfusion and its association with left ventricular (LV) systolic function in AMI patients undergoing complete revascularization.

AMI patients who underwent complete revascularization were prospectively enrolled, and hybrid positron emission tomography/magnetic resonance (PET/MR) was performed at 2 months and 1 year. Hypoperfused myocardium was defined as myocardium with reduced perfusion and normal metabolism.

Forty-five patients (59.80 ± 10.68 years, 80.0% male) were enrolled, and hypoperfused myocardium (median: 12% of LV) was detected in 21 (46.7%) patients 2 months post-AMI. Patients with hypoperfused myocardium (Group A) had significantly higher hypersensitive C-reactive protein (hs-CRP) (p = 0.016) and lower T2 value (p = 0.010) than those without (Group B). In the follow-up PET/MR at 1 year, significant LV ejection fraction improvement was observed in Group A (56.39 ± 9.76% vs. 54.58 ± 10.39%, p = 0.016) but not in Group B (51.63 ± 13.09% vs. 50.79 ± 16.95%, p = 0.615). Six (31.6%) patients in Group A showed recovery of perfusion, of which there were more females (p = 0.025), fewer diabetics (p = 0.044), or overweight (p = 0.035), with better global longitudinal strain (GLS) (p = 0.005).

Myocardial hypoperfusion is not rare and evolves over time in AMI patients undergoing complete revascularization, of which the reversal is probably associated with improved LV systolic function.

Structured Graphical Abstract