Format

Send to

Choose Destination
Cardiovasc Revasc Med. 2019 Feb 16. pii: S1553-8389(19)30091-0. doi: 10.1016/j.carrev.2019.01.022. [Epub ahead of print]

Incremental value of coronary microcirculation resistive reserve ratio in predicting the extent of myocardial infarction in patients with STEMI. Insights from the Oxford Acute Myocardial Infarction (OxAMI) study.

Author information

1
Oxford Heart Centre, NIHR Biomedical Research Centre, Oxford University Hospitals, Oxford, UK; Division of Cardiology, Department of Medicine, University of Verona, Verona, Italy.
2
Oxford Heart Centre, NIHR Biomedical Research Centre, Oxford University Hospitals, Oxford, UK.
3
Oxford Heart Centre, NIHR Biomedical Research Centre, Oxford University Hospitals, Oxford, UK; Division of Cardiovascular Medicine, BHF Centre of Research Excellence, University of Oxford, Oxford, UK.
4
Acute Vascular Imaging Centre, Radcliffe Department of Medicine, University of Oxford, Oxford, UK; Division of Cardiovascular Medicine, BHF Centre of Research Excellence, University of Oxford, Oxford, UK.
5
Oxford Heart Centre, NIHR Biomedical Research Centre, Oxford University Hospitals, Oxford, UK; Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK.
6
Division of Cardiology, Department of Medicine, University of Verona, Verona, Italy.
7
Oxford Heart Centre, NIHR Biomedical Research Centre, Oxford University Hospitals, Oxford, UK. Electronic address: adrian.banning@ouh.nhs.uk.

Abstract

BACKGROUND:

Resistive reserve ratio (RRR) is a novel index that expresses the ratio between basal and hyperemic microcirculatory resistance. We sought to compare the performance of RRR, coronary flow reserve (CFR) and index of microcirculatory resistance (IMR) in predicting the extent of infarct size (IS) after ST-elevation myocardial infarction.

METHODS:

Thermodilution parameters were measured after primary percutaneous coronary intervention (PPCI) in 45 patients. In 30 (67%) cases pre-stenting measurements were also performed to assess the effect of PPCI on myocardial reperfusion, defined by CFR. Cardiovascular magnetic resonance (CMR) was performed at 48-h to assess area-at-risk (AAR), microvascular obstruction (MVO) and IS. CMR was repeated at 6 months in 39/45 patients.

RESULTS:

RRR (AUCRRR = 0.85, CI: 0.71-0.99) performed better compared to CFR (AUCCFR = 0.67, CI: 0.48-0.86) and IMR (AUCIMR = 0.70, CI: 0.52-0.88) in predicting IS% at 6-months. Patients with impaired RRR showed larger acute-IS% (27.4 [14.5-42.5] vs 15.4 [8.3-26], p = 0.018), MVO% (3.44 [0-5.97] vs 0 [0-0.89], p = 0.026), AAR% (43 [35-52] vs 34 [25-46], p = 0.03) and 6-months-IS% (22.7 [10.2-35] vs 8.8 [6.9-12.3], p = 0.006), higher rate of adverse remodeling (22.2% vs 0%, p = 0.04) and lower myocardial salvage index (34% [22.8-59.2] vs 53.2% [37.7-71], p = 0.032) compared with other patients. Furthermore, RRR but not IMR or CFR resulted independently associated with 6-months-IS%. CFR (1.48 ± 0.87 vs 1.47 ± 0.61, p = 0.94) did not improve after PPCI in patients with impaired RRR, whereas it improved significantly in other patients (CFR: 1.37 ± 0.43 vs 1.93 ± 0.49, p = 0.018).

CONCLUSIONS:

Patients with post-PPCI impaired RRR were more likely to have suboptimal myocardial reperfusion and larger IS at follow-up. RRR may offer incremental prognostic value compared with other thermodilution-derived indices.

KEYWORDS:

Cardiovascular magnetic resonance; Coronary flow reserve; Index of microvascular resistance; Resistive reserve ratio; ST-elevation myocardial infarction

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center