Background: Acute coronary artery disease (CAD) manifests as acute coronary syndrome (ACS) or sudden cardiac death (SCD), yet the risk for these sudden events by culprit artery is unknown. We compared culprits in ACS (STEMI, NSTEMI, UA) from two referral centers to autopsy-defined SCDs over a 37-month period in San Francisco (SF) County.
Methods: We reviewed all cardiac procedures at SF General Hospital and UCSF Medical Center and associated records from 2/1/2011 to 3/1/2014. Culprit arteries were defined as receiving intervention or with most acute lesion on film review: left main (LM), left anterior descending (LAD), left circumflex (LCx), right coronary (RCA). We identified all contemporaneous countywide SCDs via active surveillance of all out of hospital (OOH) deaths reported to the Medical Examiner in the SF POstmortem Systematic InvesTigation of Sudden Cardiac Death (POST SCD) study. We identified culprit arteries for SCDs due to acute CAD after autopsy, toxicology, and histology.
Results: We identified 362 (198 STEMI, 119 NSTEMI, 45 UA) ACS patients and an additional 46 (40 STEMI, 6 NSTEMI) OOH resuscitated cardiac arrests. 26 of 408 (6.4%) died during hospitalization (ACS deaths). 525 of 541 (97%) OOH SCDs were autopsied; we identified 66 (12.6%) due to acute CAD (52 arrhythmic, 12 ventricular rupture, 2 pump failure). Mean ages of SCDs, ACS deaths, and ACS survivors to discharge were 68.5, 62.5, 62.4 years, respectively; 25.9% were women. Whites were most likely to have SCD (p=0.0003) and survive ACS (p=0.02). LAD was the most common culprit in SCD (42.4%) and ACS (44.5%). Compared to reference LCx culprits, RCA had highest risk for STEMI (RR 2.8, 95% CI 1 to 7.8, P=0.05) and LM highest for ACS death (RR 12.6, 95% CI 2.4 to 68.1, P=0.003), adjusted for age, sex, race, HTN, hyperlipidemia, diabetes, and smoking. Risk for OOH SCD was similar for all arteries (p>0.1). 67% of female ACS deaths were due to RCA culprits vs. 6% in men (p=0.0009).
Conclusions: In this countywide investigation of presentations for acute CAD, risk for OOH SCDs was similar for all culprit arteries, but risk for death after ACS was highest for LM lesions. RCA culprits had highest risk for STEMI, and ACS deaths in women. These findings may guide risk assessment for CAD lesions by anatomic location and sex.