TRANSRADIAL VS. TRANSFEMORAL ACCESS FOR CARDIAC CATHETERIZATION IN NON-ST ELEVATION ACUTE CORONARY SYNDROME: A META-ANALYSIS

Abstract

BACKGROUND: In 2012, we reported on a novel “physicianless” automated system of pre-hospital ST elevation myocardial infarction (STEMI) diagnosis and cardiac catheterization laboratory (CCL) activation. Our analysis at that time demonstrated consistently short door-to-balloon (D2B) times and an acceptable low rate of inappropriate activations (IA). Nevertheless, a number of targets for protocol improvement were identified and implemented. Herein, we report on the impact of these changes on the performance of the activation algorithm. METHODS: Patient data were collected for all pre-hospital CCL activation from February 2010 to January 2015. ECG’s were performed by first-responders in the field for all patients with a complaint of chest pain or dyspnea. An electrographic diagnosis of STEMI (Zoll Medical Corporation) resulted automatically in CCL activation and direct transfer without physician interpretation of the ECG. Inappropriate activation was defined as any activation resulting from a non-diagnostic ECG (No ST-elevation, judged independently by 2 cardiologist reviewers). Identified inappropriate activations were then analyzed for the reasons for erroneous CCL activation. Human error was defined as an improper application of the referral algorithm. Machine error was defined as an incorrect automated diagnosis of STEMI for a tracing of adequate quality. In March 2013, the protocol was amended to exclude tachycardia >140bpm from automatic CCL activation and an educational campaign was implemented for ambulance technicians in order to ensure proper application of the referral algorithm. RESULTS: Over the study period, we identified 489 prehospital CCL activations for STEMI (155 before protocol amendment). Full results will be presented at congress. The first 253 activations are presented here. Patient characteristics were similar both before and after protocol amendment. 225 patients (89%) presented ST-elevation on the ECG (ECG-appropriate; 213 confirmed STEMI and 12 ST-elevations without coronary occlusion). The remaining 28 activations (11%) were considered inappropriate. Of these, 19 occurred prior to protocol amendment and 9 occurred after. The IA rate therefore decreased from 12% to 9% (25% relative reduction) with our intervention. CONCLUSION: Pre-hospital “physician-less” automated STEMI diagnosis provided durable performance characteristics in terms of both false positive and inappropriate CCL activation. Moreover, simple interventions appear to result in further meaningful reductions in the rate of IA. 040 TRANSRADIAL VS. TRANSFEMORAL ACCESS FOR CARDIAC CATHETERIZATION IN NON-ST ELEVATION ACUTE CORONARY SYNDROME: A META-ANALYSIS