Feasibility and efficacy of delayed pharmacoinvasive therapy for ST-elevation myocardial infarction

Background: ST-elevation myocardial infarction (STEMI) refers to a clinical syndrome that features symptoms of myocardial ischemia with consequent ST-elevation on electrocardiography and an associated rise in cardiac biomarkers. Rapid restoration of brisk flow in the coronary vasculature is critical in reducing mortality and morbidity. In patients with STEMI who could not receive primary percutaneous coronary intervention (PCI) on time, pharmacoinvasive strategy (thrombolysis followed by timely PCI within 3-24 h of its initiation) is an effective option.

Aim: To analyze the role of delayed pharmacoinvasive strategy in the window period of 24-72 h after thrombolysis.

Methods: This was a physician-initiated, single-center prospective registry between January 2017 and July 2017 which enrolled 337 acute STEMI patients with partially occluded coronary arteries. Patients received routine pharmacoinvasive therapy (PCI within 3-24 h of thrombolysis) in one group and delayed pharmacoinvasive therapy (PCI within 24-72 h of thrombolysis) in another group. The primary endpoint was major adverse cardiac and cerebrovascular events (MACCE) within 30 d of the procedure. The secondary endpoints included major bleeding as defined by Bleeding Academic Research Consortium classification, angina, and dyspnea within 30 d.

Results: The mean age in the two groups was comparable (55.1 ± 10.1 years vs 54.2 ± 10.5 years, P = 0.426). Diabetes was present among 20.2% and 22.1% of patients in the routine and delayed groups, respectively. Smoking rate was 54.6% and 55.8% in the routine and delayed groups, respectively. Thrombolysis was initiated within 6 h of onset of symptoms in both groups (P = 0.125). The mean time from thrombolysis to PCI in the routine and delayed groups was 16.9 ± 5.3 h and 44.1 ± 14.7 h, respectively. No significant difference was found for the occurrence of measured clinical outcomes in the two groups within 30 d (8.7% vs 12.9%, P = 0.152). Univariate analysis of demographic characteristics and risk factors for patients who reported MACCE in the two groups did not demonstrate any significant correlation. Secondary endpoints such as angina, dyspnea, and major bleeding were non-significantly different between the two groups.

Conclusion: Delayed PCI pharmacoinvasive strategy in a critical diseased but not completely occluded artery beyond 24 h in patients who have been timely thrombolyzed seems a reasonable strategy.