Absence of baseline Q waves in STEMI was associated with a lower 30-day composite outcome compared to presence of Q waves (6.7% vs 13.7%; HR 0.68; P=0.001).
Cohort (n=967)
Does a pharmacoinvasive strategy improve reperfusion and clinical outcomes compared to primary PCI in STEMI patients stratified by baseline Q wave status?
In STEMI patients, a pharmacoinvasive strategy was associated with enhanced reperfusion compared to primary PCI irrespective of baseline Q waves, with the best 1-year clinical outcomes seen in patients without Q waves receiving pharmacoinvasive therapy.
Effect estimate: HR 0.68 (95% CI 0.48-0.96)
Absolute Event Rate: 6.7% vs 13.7%
p-value: p=0.001
BACKGROUND: Previous studies indicate the presence of baseline Q waves in ST-elevation myocardial infarction (STEMI) is a stronger predictor of clinical outcomes than duration of symptoms. Whether reperfusion strategy modifies outcomes after accounting for baseline Q waves is unknown. We compared electrocardiogram reperfusion indices and clinical outcomes between a pharmacoinvasive and primary percutaneous coronary intervention (pPCI) strategy according to baseline Q wave status. METHODS: We studied 967 patients from the Alberta STEMI VHR registry (2017-2021), stratified by baseline Q wave and reperfusion strategy. Core-laboratory ST segment resolution (ST-R) was analyzed. The primary composite outcome was all-cause death, congestive heart failure, cardiogenic shock, and recurrent MI. RESULTS: Median symptom onset to first medical contact was 71 minutes; 21.8% of patients had baseline Q waves. Compared to patients with Q waves, those without had greater ST-R (79.0% vs 61.6%, P<0.001, adjusted OR 2.28, 95%CI 1.66-3.14) and lower 30-day composite outcome (6.7% vs 13.7%, P=0.001; adjusted HR 0.68, 95%CI 0.48-0.96). Regardless of baseline Q waves, pharmacoinvasive was associated with better ST-R than pPCI (no Q waves: 85.6% vs 70.3%, P<0.001; adjusted OR 2.76, 95%CI 1.82-4.19; Q waves: 69.5% vs 50.6%, P=0.006; adjusted OR 1.95, 95%CI 1.06-3.59). At 1-year, the primary outcome was lowest among patients without baseline Q waves treated with pharmacoinvasive therapy (log-rank P<0.001). CONCLUSIONS: In STEMI patients receiving timely reperfusion in our registry, baseline Q waves were associated with poorer reperfusion and worse clinical outcomes. A pharmacoinvasive strategy was associated with enhanced reperfusion irrespective of baseline Q waves, with the greatest value appearing to be in patients without Q waves.
Kay et al. (Mon,) conducted a cohort in ST-elevation myocardial infarction (STEMI) (n=967). Absence of baseline Q waves vs. Presence of baseline Q waves was evaluated on Composite of all-cause death, congestive heart failure, cardiogenic shock, and recurrent MI (HR 0.68, 95% CI 0.48-0.96, p=0.001). Absence of baseline Q waves in STEMI was associated with a lower 30-day composite outcome compared to presence of Q waves (6.7% vs 13.7%; HR 0.68; P=0.001).