Prognostic value of stress cardiovascular magnetic resonance in patients with ischaemic heart disease and severely reduced left ventricular ejection fraction.

BACKGROUND

The concept of ischaemia for therapeutic guidance and risk stratification in coronary artery disease has been challenged in recent years. In particular, there is limited understanding of the prognostic value of ischaemia in patients with severely reduced left ventricular ejection fraction (LVEF). The aim of this study was to investigate the prognostic value of stress cardiovascular magnetic resonance (stress CMR) in patients with ischaemic heart disease (IHD) and severely reduced LVEF.

METHODS

This retrospective study included patients with IHD and an LVEF ≤35% who underwent stress CMR between 2009 and 2022. The primary endpoint was the occurrence of a major adverse cardiovascular event (MACE), including cardiac death, non-fatal myocardial infarction (MI), survived sudden cardiac death and implanted cardioverter defibrillator shock for ventricular fibrillation. The secondary combined endpoint included heart failure hospitalisation, percutaneous coronary intervention, arrhythmia and coronary artery bypass grafting (CABG). All-cause death was also documented.

RESULTS

The study population consisted of 362 patients (85.6% men, 70.5 (63.0-78.0) years) with an LVEF of 30.2% (25.2%-33.0%). 245 patients (67.6%) had three vessel disease, 206 patients (57.2%) had a history of MI and 83 patients (22.9%) had a history of CABG. Stress CMR showed ischaemia in 72 (19.9%) patients. Among those, 32 patients (8.8%) underwent early revascularisation. Follow-up was 4.5 (3.0-6.6) years. MACE occurred in 101 patients (27.9%), including 41 cases of cardiac death (11.3%) and 40 cases of MI (11.0%). Ischaemia was not significantly associated with MACE, the combined secondary endpoint, or all-cause death in survival analysis (HR for MACE 1.20, 95% CI 0.74 to 1.95, p=0.4).

CONCLUSION

In a cohort of patients with IHD and severely reduced LVEF, outcome did not differ when stratifying by ischaemia on stress CMR. We found no evidence that ischaemia could identify patients with increased risk for MACE, the combined secondary endpoint or all-cause death.