Baseline risk, time window, and indications for delayed percutaneous coronary interventions, their significance in treatment of ST-segment elevation myocardial infarction

Abstract

The aim of the study was to estimate the significance of delayed percutaneous coronary interventions (PCIs) in the treatment of ST-segment elevation myocardial infarction (STEMI), to weigh the initial mortality risk (MR) while determining the indications for their use and the time window for the use of mechanical reperfusion in late hospital admission. Total 2226 patients admitted to the Institute with STEMI for the period 2008–2017 were studied. Emergency coronary angiography was performed in 945 admitted patients in the initial 12 hours and in 834 patients after 12–72 hours of STEMI onset; PCI was performed in 784 and 619 patients, respectively. In all patients, MR was scored by TIMI; angiographic success was assessed as TIMI 3 coronary flow and compared to ECG signs of reperfusion. The baseline MR score averaged 5 or 12.5%, being corresponded to score 4.2 or 8% in patients with PCI performed in the initial 12 hours, score 5 or 12.5% in those with PCI performed after 12–72 hours, and score 6 or 16% in patients without PCI; or with respect to the patient age, MR scored 3.7 or 7%, 6 or 16%, and 7.5 or 25%, for those under the age of 65 years, those from 65–75 years, and those over 75 years old, respectively. Mortality in patients with an early and delayed PCI was 5.2% and 4.2%, respectively, and 15.6% in patients without PCI; after patient distribution by age under 65, 65–75, and over 75 years old, the respective mortality rates were 3.8%, 4.9%, and 10.8% after an early PCI; 2.6%, 5.8%, and 8.2% after a delayed PCI; and 8.4%, 19.4%, and 28% among those without PCI. For 10 years, the number of primary PCIs had increased from 39% to 78%. The ratio of early to delayed PCI made 56% to 44%. Of 195 deaths (67 patients with PCI and 128 without PCI), 90% of patients had a three-vessel disease; 83% of patients had the MI area over 30%; and the cause of death in 84% was pulmonary edema. The presented data suggest a high practical significance of delayed PCI in patients with initially high MR, its most weighty components being the age over 75 years and severe manifestations of acute heart failure (AHF). Unlike early PCIs, the delayed PCIs are used less frequently, the initial MR is not taken into account, and they are abstained from in respect to people over 75 years of age. The reduction in mortality, proportional to the baseline MR, suggests their correlation to PCI results and the feasibility of PCI use without age restrictions. The use of primary PCIs in late hospital admissions, by analogy with early ones or selectively in high MR, will help to optimize the treatment tactics and minimize mortality.