A case-crossover study of ST-elevation myocardial infarction and organic carbon and source-specific PM2.5 concentrations in Monroe County, New York.

Background: Previous work reported increased rates of cardiovascular hospitalizations associated with increased source-specific PM2.5 concentrations in New York State, despite decreased PM2.5 concentrations. We also found increased rates of ST elevation myocardial infarction (STEMI) associated with short-term increases in concentrations of ultrafine particles and other traffic-related pollutants in the 2014-2016 period, but not during 2017-2019 in Rochester. Changes in PM2.5 composition and sources resulting from air quality policies (e.g., Tier 3 light-duty vehicles) may explain the differences. Thus, this study aimed to estimate whether rates of STEMI were associated with organic carbon and source-specific PM2.5 concentrations. Methods: Using STEMI patients treated at the University of Rochester Medical Center, compositional and source-apportioned PM2.5 concentrations measured in Rochester, a time-stratified case-crossover design, and conditional logistic regression models, we estimated the rate of STEMI associated with increases in mean primary organic carbon (POC), secondary organic carbon (SOC), and source-specific PM2.5 concentrations on lag days 0, 0-3, and 0-6 during 2014-2019. Results: The associations of an increased rate of STEMI with interquartile range (IQR) increases in spark-ignition emissions (GAS) and diesel (DIE) concentrations in the previous few days were not found from 2014 to 2019. However, IQR increases in GAS concentrations were associated with an increased rate of STEMI on the same day in the 2014-2016 period (Rate ratio [RR] = 1.69; 95% CI = 0.98, 2.94; 1.73 µg/m3). In addition, each IQR increase in mean SOC concentration in the previous 6 days was associated with an increased rate of STEMI, despite imprecision (RR = 1.14; 95% CI = 0.89, 1.45; 0.42 µg/m3). Conclusion: Increased SOC concentrations may be associated with increased rates of STEMI, while there seems to be a declining trend in adverse effects of GAS on triggering of STEMI. These changes could be attributed to changes in PM2.5 composition and sources following the Tier 3 vehicle introduction.

Short-term Deaths After Percutaneous Coronary Intervention Discharge: Prevalence, Risk Factors, and Hospital Risk-Adjusted Mortality.

Background: Little is known about patients who die shortly after discharge following any procedures, including percutaneous coronary intervention (PCI). Our aim was to explore the implications of using 30-day deaths after discharge as part of a quality measure for PCI. Methods: New York State's PCI registry was used to find PCI deaths that occurred after discharge within 30 days of the procedure from January 1, 2015, to November 30, 2017. Patient risk factors and hospital risk-adjusted 30-day mortality before and after discharge were also investigated. Results: A total of 2121 (1.55%) patients who underwent PCI died within 30 days of the index procedure, and 730 (34.4%) deaths occurred after discharge, with 30% of deaths after discharge (10% of all deaths) occurring during readmission. Among nonemergency patients, 56% of 30-day deaths occurred after discharge. No risk-adjusted 30-day in-hospital and after-discharge hospital mortality outliers were in common. Only 4 of 10 low outliers and 6 of 10 high outliers for 30-day in-hospital mortality and 30-day total (in-hospital plus after-discharge) mortality were in common. Conclusions: A large percentage of early deaths after PCI occur after discharge, particularly among lower-risk patients. Future efforts should be focused on monitoring these patients. Hospital risk-adjusted mortality assessments are impacted substantially by inclusion of after-discharge deaths, and decisions about their inclusion will affect quality assessment and public reporting initiatives. The pros and cons of including them should be examined carefully.