Cancellation of the Cardiac Catheterization Lab After Activation for ST-Segment-Elevation Myocardial Infarction

Area of Science:

• Cardiology
• Emergency Medicine
• Medical Diagnostics

Background:

• Prehospital electrocardiogram (ECG) activation of cardiac catheterization laboratories (CCL) for ST-segment-elevation myocardial infarction (STEMI) aims to reduce door-to-balloon times.
• CCL cancellations (CCL^X) represent a significant challenge in STEMI care pathways.
• Understanding the reasons for CCL^X and their impact on patient outcomes is crucial for quality improvement.

Purpose of the Study:

• To investigate the reasons for CCL^X in STEMI activations.
• To compare the clinical characteristics and outcomes of patients undergoing emergent coronary angiography (EA) versus those with CCL^X.
• To identify factors associated with CCL^X and their impact on mortality.

Main Methods:

• Retrospective review of 1332 consecutive CCL activations from January 2012 to December 2014.
• Data analysis comparing patients who received EA (n=466) versus those with CCL^X (n=866).
• Multivariate logistic regression used to identify predictors of EA versus CCL^X, with a focus on age, peak troponin, and initial ECG findings.

Main Results:

• Common reasons for CCL^X included bundle branch block (21%), poor-quality prehospital ECG (18%), and non-STEMI ST changes (18%).
• CCL^X patients were older, more likely to be women, and had higher rates of prior coronary artery bypass grafting or paced rhythms.
• All-cause mortality did not differ significantly at 1 year or during the study period (15.8% EA vs. 16.2% CCL^X). However, cardiac death was higher in the EA group (11.8% vs. 3.0%).
• After adjustment, CCL^X was associated with an increased risk for all-cause mortality (hazard ratio, 1.82).

Conclusions:

• Prehospital ECGs without overreading or transmission contribute to frequent CCL^X.
• Despite similar short-term mortality, CCL^X patients represent a high-risk population.
• Further research is needed to implement quality improvement initiatives to reduce CCL^X rates and improve clinical outcomes.