Impact of Door-to-Balloon Time Reduction Depending on the Killip Classification in Patients with ST-Segment Elevation Myocardial Infarction Transported by Emergency Medical Services

Optimal door-to-balloon time for primary percutaneous coronary intervention for ST-elevation myocardial infarction

BACKGROUND

Door-to-balloon time (DTBT) for ST-elevation myocardial infarction (STEMI) is a performance metric by which primary percutaneous coronary intervention (PPCI) services are assessed.

METHODS

Consecutive patients presenting with STEMI undergoing PPCI between January 2007 to December 2019 from the Singapore Myocardial Infarction Registry were included. Patients were stratified based on DTBT (≤60 min, 61-90 min, 91-180 min) and Killip status (I-III vs. IV). Outcomes assessed included all-cause mortality and major adverse cardiovascular events (MACE) at 30-days and 1-year.

RESULTS

In total, 13,823 patients were included, with 82.59% achieving DTBT ≤90 min and 49.77% achieving DTBT ≤60 min. For Killip I-III (n = 11,591,83.85%), the median DTBT was 60[46-78]min. The 30-day all-cause mortality for DTBT of ≤60 min, 61-90 min and 91-180 min was 1.08%, 2.17% and 4.33% respectively (p < 0.001). On multivariate analysis, however, there was no significant difference for 30-day and 1-year outcomes across all DTBT (p > 0.05). For Killip IV, the median DTBT was 68[51-91]min. The 30-day all-cause mortality for DTBT of ≤60 min, 61-90 min and 91-180 min was 11.74%, 20.48% and 35.06% respectively (p < 0.001). On multivariate analysis for 30-day and 1-year outcomes, DTBT 91-180 min was an independent predictor of worse outcomes (p < 0.05), but there was no significant difference between DTBT of ≤60 min and 61-90 min (p > 0.05).

CONCLUSION

In Killip I-III patients, DTBT had no significant impact on outcomes upon adjustment for confounders. Conversely, for Killip IV patients, a DTBT of >90 min was associated with significantly higher adverse outcomes, with no differences between a DTBT of ≤60 min vs. 61-90 min. Outcomes in STEMI involve a complex interplay of factors and recommendations of a lowered DTBT of ≤60 min will require further evaluation.

Impact of chest pain center quality control indicators on mortality risk in ST-segment elevation myocardial infarction patients: a study based on Killip classification

Background

Despite the crucial role of Chest pain centers (CPCs) in acute myocardial infarction (AMI) management, China's mortality rate for ST-segment elevation myocardial infarction (STEMI) has remained stagnant. This study evaluates the influence of CPC quality control indicators on mortality risk in STEMI patients receiving primary percutaneous coronary intervention (PPCI) during the COVID-19 pandemic.

Methods

A cohort of 664 consecutive STEMI patients undergoing PPCI from 2020 to 2022 was analyzed using Cox proportional hazards regression models. The cohort was stratified by Killip classification at admission (Class 1: n = 402, Class ≥2: n = 262).

Results

At a median follow-up of 17 months, 35 deaths were recorded. In Class ≥2, longer door-to-balloon (D-to-B) time, PCI informed consent time, catheterization laboratory activation time, and diagnosis-to-loading dose dual antiplatelet therapy (DAPT) time were associated with increased mortality risk. In Class 1, consultation time (notice to arrival) under 10 min reduced death risk. In Class ≥2, PCI informed consent time under 20 min decreased mortality risk.

Conclusion

CPC quality control metrics affect STEMI mortality based on Killip class. Key factors include time indicators and standardization of CPC management. The study provides guidance for quality care during COVID-19.