Authors (including presenting author) :
Lee PH
Affiliation :
Division of Cardiology, Department of Medicine, Queen Elizabeth Hospital
Introduction :
Acute ST-elevation myocardial infarction (STEMI) represents a unique patient population carrying high morbidity and mortality. Timely and effective coronary reperfusion is the major determinant of patient outcome. In Hong Kong, thrombolytic therapy remains the mainstay of reperfusion strategy in STEMI patients presenting outside office hours. A pilot cluster-based 24-hour primary percutaneous coronary intervention (PCI) program was launched in October 2018 with Kowloon Central Cluster being the leading cluster in this phased expansion program.
Objectives :
To compare the 30-day mortality and major bleeding event in patients receiving historical thrombolytic therapy and primary PCI as the reperfusion strategy for patients with acute STEMI presenting outside office hours.
Methodology :
A single center retrospective study was conducted in Queen Elizabeth Hospital (Hong Kong) on consecutive patients presenting outside office hours with a diagnosis of acute STEMI, who received urgent thrombolytic therapy as the reperfusion strategy between January 2016 and September 2018 and primary PCI between October 2018 and December 2019. The primary endpoints were 30-day mortality and major bleeding event. Major bleeding event was defined as Bleeding Academic Research Consortium (BARC) type 3 or above. The secondary endpoints were thrombolytic failure rate, unplanned revascularization and hospital length of stay. A subgroup analysis on major primary outcomes was also performed in 2 subsets of population: age ≥ 75 and early presentation ≤ 3 hours.
Result & Outcome :
188 patients in thrombolytic group and 143 patients in primary PCI group were analyzed. 30-day mortality occurred in 11.7% and 4.2% of patients in thrombolytic therapy group and primary PCI group respectively (P = .02). Major bleeding events occurred in 8% and 2.1% in thrombolytic and primary PCI group respectively (P = .02). Among the subset of patients who presented early (≤ 3 hours from symptoms onset), there was a trend towards lower mortality rate (4.9% vs 6.8%) and fewer major bleeding events (3.7% vs 6%) in primary PCI group, though the differences were not statistically significant. Among the subset of elderly population (age ≥ 75), primary PCI group had a significantly lower composite outcome (17.6% vs 41.9%, P = .03) and fewer major bleeding events (8.8% vs 29%, P = .04). Regarding mortality in this subset, primary PCI group had a lower 30-day mortality rate (17.6% vs 38.7%, P = .06), though it did not reach statistical significance. All primary outcome events (30-day mortality and major bleeding event) in primary PCI group occurred in elderly population (age ≥ 75). Thrombolytic failure occurred in 31.4% of patients and unplanned revascularization in 25.5% of patients receiving thrombolytic therapy. The median lengths of stay were not different between the two groups (5 [IQR 4-7] days vs 4 [IQR 3-7] days, P = .29).
