Abstract 3336: Fractional and Coronary Flow Reserve in Prediction of Functional Recovery of Myocardium in Patients with Previous Myocardial Infarction
Background: Fractional flow reserve (FFR) may provide clinically useful diagnostic information both in patients (pts) with normal left ventricular (LV) function as well as in pts with previous myocardial infarction (MI). However, the question remains to the relation between improvement of FFR and improvement of LV function in pts with previous MI undergoing percutaneous coronary intervention (PCI).
Aim: The aim of the study was to evaluate the relation between FFR and simultaneously evaluated coronary flow reserve by thermodilution (CFRthermo), with functional improvement of LV function in pts with previous MI undergoing PCI.
Methods: Study population consisted of 50 pts (mean age 53±8 years; 40 male) with previous MI and significant coronary stenosis in one-vessel CAD (33 LAD, 4 Cx, 13 RCA) undergoing PCI of infarct-related coronary artery. In all pts we have evaluated by single pressure/thermo wire FFR and CFRthermo before and immediately after PCI. In all pts, we have evaluated LV ejection fraction by echo and wall motion score index (WMSI) before and 3 months after PCI.
Results: Coronary lesions were successfully treated in all pts with decrease of diameter stenosis from 63±7% to 18±9% (p<0.001). FFR increased significantly (p<0.001) from 0.62±0.15 to 0.91±0.06 after PCI, whereas CFRthermo increased significantly (p<0.01) from 1.5±0.3 to 2.5±0.7. LV ejection fraction increased from 49±6% to 55±8% (p<0.0001), and WMSI decreased from 1.44±0.24 to 1.29±0.29 (p<0.0001). LV functional improvement was observed in 33/50 (66%) of pts. In pts with LV functional recovery in comparison to pts with no recovery there was significant difference in FFR before PCI (0.57±0.15 vs. 0.71±0.11, p=0.001), improvement of FFR during PCI (0.34±0.15 vs. 0.21±0.13, p=0.004), improvement of CFRthermo during PCI (1.2±0.6 vs. 0.6±0.5, p=0.001) and CFRthermo after PCI (2.7±0.7 vs. 2.1±0.6, p=0.008), respectively.
Conclusion: Evaluation of FFR and CFRthermo provide significant prognostic information on LV functional recovery in pts with previous MI undergoing PCI. Lower FFR before PCI, higher CFRthermo after PCI, as well as higher improvement of FFR and CFRthermo during PCI are indicative of left ventricular functional improvement in pts with previous MI.