Prognostic Value of Persistent Microvascular Obstruction on Follow-Up Cardiac MRI After Reperfused STEMI

Area of Science:

• Cardiology
• Cardiovascular Imaging
• Interventional Cardiology

Background:

• The prognostic significance of persistent microvascular obstruction (MVO) in ST-segment elevation myocardial infarction (STEMI) patients following percutaneous coronary intervention (PCI) is not well-established.
• Understanding MVO's impact is crucial for risk stratification and management strategies.

Purpose of the Study:

• To evaluate the prognostic value of persistent MVO in patients with reperfused STEMI.
• To determine if persistent MVO predicts adverse cardiovascular outcomes.

Main Methods:

• Retrospective analysis of 504 STEMI patients undergoing primary PCI.
• Follow-up cardiac magnetic resonance (CMR) at ≥60 days post-PCI to assess persistent MVO using late gadolinium enhancement (LGE).
• Composite endpoint of heart failure (HF) events, including HF-related death, transplantation, LVAD implantation, and HF hospitalization, analyzed using competing risk models.

Main Results:

• Persistent MVO was identified in 8.7% of STEMI patients.
• Patients with persistent MVO had significantly lower left ventricular ejection fraction, larger end-diastolic volume index, and greater LGE extent.
• Persistent MVO improved the predictive model for HF events, enhancing discrimination, fit, and risk reclassification (C-index increased from 0.78 to 0.82).

Conclusions:

• Persistent MVO is present in a notable subset of STEMI patients at ≥60 days post-PCI.
• Persistent MVO serves as an independent predictor of HF-related events.
• Incorporating persistent MVO into risk models offers incremental prognostic value for STEMI patients.