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Published on: June 28, 2019
Prognostic Value of Microvascular Resistance Reserve After Percutaneous Coronary Intervention in Patients With
Rob Eerdekens1, Mohamed El Farissi1, Giovanni Luigi De Maria2
1Department of Cardiology, Catharina Hospital, Eindhoven, the Netherlands.
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 < 0.001) in the low MRR (≤1.25) and high MRR (>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.
Insights
Microvascular resistance reserve (MRR) predicts long-term outcomes in ST-segment elevation myocardial infarction (STEMI) patients. Lower MRR post-procedure indicates a higher risk of mortality or heart failure hospitalization.
Area of Science:
- Cardiology
- Microcirculation Research
- Interventional Cardiology
Background:
- Microvascular resistance reserve (MRR) is a new index for assessing microcirculation's vasodilatory capacity, independent of epicardial disease.
- The prognostic significance of MRR in ST-segment elevation myocardial infarction (STEMI) has not been established.
Purpose of the Study:
- To evaluate the prognostic value of MRR in STEMI patients.
- To compare MRR with cardiovascular magnetic resonance imaging parameters.
Main Methods:
- Pooled analysis of 1,265 STEMI patients who underwent primary percutaneous coronary intervention.
- Subgroup analysis of 446 patients with available MRR and index of microcirculatory resistance (IMR) measurements.
- Primary endpoint: composite of all-cause mortality or heart failure hospitalization.
Main Results:
- An MRR cutoff of 1.25 was optimal for predicting the primary endpoint.
- Patients with low MRR (≤1.25) had a significantly higher risk (HR: 4.16) of mortality or heart failure hospitalization compared to those with high MRR (>1.25).
- Both IMR and MRR independently predicted adverse outcomes.
Conclusions:
- MRR measured immediately after primary percutaneous coronary intervention is an independent predictor of long-term mortality or heart failure hospitalization in STEMI patients.
