Low microvascular resistance reserve (≤1.25) measured directly after primary PCI significantly increased the risk of all-cause mortality or hospitalization for heart failure compared to high MRR (HR 4.16).
Cohort (n=446)
Yes
Does low microvascular resistance reserve (MRR ≤1.25) predict increased risk of all-cause mortality or hospitalization for heart failure in patients with STEMI after primary PCI?
Microvascular resistance reserve (MRR) measured directly after primary PCI is a strong, independent predictor of long-term mortality and heart failure hospitalization in patients with STEMI.
Effect estimate: HR 4.16 (95% CI 2.31-7.50)
Absolute Event Rate: 27.3% vs 5.9%
p-value: p=<0.001
BACKGROUND The microvascular resistance reserve (MRR) has recently been introduced as a novel index to assess the vasodilatory capacity of the microcirculation, independent of epicardial disease. The prognostic value of MRR in ST-segment elevation myocardial infarction (STEMI) is unknown. OBJECTIVES The aim of this analysis was to investigate the prognostic value of MRR in patients with STEMI and to compare MRR with cardiovascular magnetic resonance imaging parameters. METHODS From a pooled analysis of individual patient data from 6 cohorts that measured the index of microcirculatory resistance (IMR) directly after primary percutaneous coronary intervention in patients with STEMI (n = 1,265), a subgroup analysis was performed in patients in whom both MRR and IMR were available. The primary endpoint was the composite of all-cause mortality or hospitalization for heart failure. RESULTS Both MRR and IMR could be calculated in 446 patients. The optimal cutoff of MRR to predict the primary endpoint in this STEMI population was 1.25. During a median follow-up of 3.1 years (Q1-Q3: 1.5-6.1 years), the composite of all-cause mortality or hospitalization for heart failure occurred in 27.3% and 5.9% of patients (HR: 4.16; 95% CI: 2.31-7.50; P 1.25) groups, respectively. Both IMR and MRR were independent predictors of the composite of all-cause mortality or hospitalization for heart failure. CONCLUSIONS MRR measured directly after primary percutaneous coronary intervention was an independent predictor of the composite of all-cause mortality or hospitalization for heart failure during long-term follow-up.
Eerdekens et al. (Wed,) conducted a cohort in ST-segment elevation myocardial infarction (STEMI) (n=446). Low microvascular resistance reserve (MRR ≤1.25) vs. High microvascular resistance reserve (MRR >1.25) was evaluated on Composite of all-cause mortality or hospitalization for heart failure (HR 4.16, 95% CI 2.31-7.50, p=<0.001). Low microvascular resistance reserve (≤1.25) measured directly after primary PCI significantly increased the risk of all-cause mortality or hospitalization for heart failure compared to high MRR (HR 4.16).