Quantitative flow ratio vs. angiography- only guided PCI in STEMI patients: a one- year outcomes

Background Coronary physiology-guided PCIs are recommended worldwide. However, invasive coronary physiology methods prolong the procedure, make additional risks for the patients, and prolong the fluoroscopy time for an interventional cardiologist. Otherwise, there is a non-invasive coronary physiology evaluation method QFR, which can be safely used even in STEMI patients. Methods 198 patients admitted with STEMI and at least one intermediate (35–75%) diameter stenosis other than culprit artery between July 2020 and June 2021 have been prospectively included in this single-centre study. All patients were randomized into one of two groups (1 - QFR-guided PCI; 2 - visual-estimation-only guided PCI). A 12-month follow-up with echocardiography, exercise stress test, and quality of life evaluation was performed in all included patients. For the QOF evaluation, the Seattle angina score questionnaire was chosen. Statistical analysis was performed using Kolmogorov-Smirnov, Stjudent T, Mann-Whitney, Pearson Chi-square tests and Kaplan Meier survival analysis. Results 98 (49.5%) patients were randomized to the first group, and 100 (50.5%) patients were included in the second group. Statistically, significantly more patients had a medical history of dyslipidaemia (98 vs 91, p = 0.002) and slightly better left ventricular ejection fraction (42.21 ± 7.88 vs 39.45 ± 9.62, p = 0.045) in the QFR group. Six times fewer patients required non-culprit artery revascularization within 12-month FU in the QFR group (1.02% vs 6%, p = 0.047). Survival analysis proved that patients in the Angio group had more than 6-time greater risk for death within a 12-month period after MI (OR 6.23, 95% CI 2.20-17.87, p = 0.006), with the highest mortality risk within the first two months after initial treatment. Conclusions Using QFR in non-culprit lesions for patients with ST-elevation myocardial infarction reduces mortality rate and revascularization in 12-month follow-up and increases the patient's quality of life. Trial registration The study was approved by the Regional Bioethical Committee and conducted under the principles of the Helsinki Declaration and local laws and regulations.