Characteristics and Outcomes of Patients With Acute Coronary Syndrome Who Received Percutaneous Coronary Intervention During Snowy Days.

Background: Acute coronary syndrome (ACS) is affected by several weather conditions. Studies from different geographical locations have yielded mixed results regarding the outcomes of patients presenting with ACS during snowy days, and we aim to report the Cleveland Clinic experience.

Methods: Patients who presented with an ACS and underwent percutaneous coronary intervention (PCI) from July 1, 2009 to September 30, 2017 were divided into ST-segment elevation myocardial infarction (STEMI), and non-ST segment elevation ACS (NSTE-ACS). According to snowy day arrival, we compared in-hospital mortality, culprit lesion anatomy, and door-to-balloon (DTB) time (in STEMI patients). Findings were confirmed in propensity-score matched cohorts.

Results: A total of 6878 patients were included: 1608 patients with STEMI (139 snowy-day vs 1469 non-snowy day PCIs) and 5270 NSTE-ACS (419 snowy-day vs 4851 non-snowy day PCIs). Right coronary artery territories accounted for most of the stented culprit lesions in all STEMI and NSTE-ACS snowy-day PCIs. While left anterior descending artery lesions were predominant in NSTE-ACS non-snowy day PCIs. There was no difference in in-hospital mortality between the snowy-day vs non-snowy day groups (4.3% vs 4.5% in the STEMI group [P=.92] and 1.2% vs 1.7% in the NSTE-ACS group [P=41]). In STEMI patients, mean DTB times were similar (43 ± 55.1 minutes vs 46.7 ± 59.6 minutes; P=.61), which remained true after hours, during weekends and holidays. Outcomes were similar in propensity-score matched cohorts.

Conclusion: At our institution, snowy days do not seem to affect in-patient mortality. In STEMI patients, DTB times were similar in those who underwent PCI regardless of the snowfall.