Pharmacoinvasive Strategy Versus Primary Percutaneous Coronary Intervention in ST-Elevation Myocardial Infarction in Clinical Practice: Insights From the Vital Heart Response Registry

Abstract

Background: Recent clinical trial data support a pharmacoinvasive strategy as an alternative to primary percutaneous coronary intervention (pPCI) in ST-segment elevation myocardial infarction. We evaluated whether this is true in a real-world prehospital ST-segment elevation myocardial infarction network using ECG assessment of reperfusion coupled with clinical outcomes within 1 year.

Methods: Of the 5583 ST-segment elevation myocardial infarction patients in the Alberta Vital Heart Response Program (Cohort 1 [2006-2011]: n=3593; Cohort 2 [2013-2016]: n=1990), we studied 3287 patients who received a pharmacoinvasive strategy with tenecteplase (April 2013: half-dose tenecteplase was employed in prehospital patients ≥75 years) or pPCI. ECGs were analyzed within a core laboratory; sum ST-segment deviation resolution ≥50% was defined as successful reperfusion. The primary composite was all-cause death, congestive heart failure, cardiogenic shock, and recurrent myocardial infarction within 1 year.

Results: The pharmacoinvasive approach was administered in 1805 patients (54.9%), (493 [27.3%] underwent rescue/urgent percutaneous coronary intervention and 1312 [72.7%] had scheduled angiography); pPCI was performed in 1482 patients (45.1%). There was greater ST-segment resolution post-catheterization/percutaneous coronary intervention with a pharmacoinvasive strategy versus pPCI (75.8% versus 64.3%, IP-weighted odds ratio, 1.59; 95% CI, 1.33-1.90; P<0.001). The primary composite was significantly lower with a pharmacoinvasive approach (16.3% versus 23.1%, IP-weighted hazard ratio, 0.84; 95% CI, 0.72-0.99; P=0.033). Major bleeding and intracranial hemorrhage were similar between a pharmacoinvasive strategy and pPCI (7.6% versus 7.5%, P=0.867; 0.6% versus 0.6%; P=0.841, respectively). In the 82 patients ≥75 years with a prehospital pharmacoinvasive strategy, similar ST-segment resolution and rescue rates were observed with full-dose versus half-dose tenecteplase (75.8% versus 88.9%, P=0.259; 31.0% versus 29.2%, P=0.867) with no difference in the primary composite (31.0% versus 25.0%, P=0.585).

Conclusions: In this large Canadian ST-segment elevation myocardial infarction registry, a pharmacoinvasive strategy was associated with improved ST-segment resolution and enhanced outcomes within 1 year compared with pPCI. Our findings support the application of a selective pharmacoinvasive reperfusion strategy when delay to pPCI exists.

Keywords: Alberta; fibrinolysis; heart failure; percutaneous coronary intervention; tenecteplase.