Diagnosis and management of wide complex tachycardia in the emergency department

Introduction While wide complex tachycardia (WCT) is potentially lethal, little is known about its incidence in the ED or about expertise of ED physicians in diagnosing and treating it. We sought to compare WCT ED cases that were primary arrhythmias versus those with rapid heart rate secondary to medical issues, as well as the accuracy of ED diagnosis and appropriateness of treatment. Methods We conducted a health records review at a large academic hospital ED staffed by 95 physicians and included consecutive patients over 28 months (2018-2020) with WCT (heart rate >= 120 bpm and QRS >= 120 ms). Cases were adjudicated for the accuracy of ECG diagnosis versus the cardiology read and for correctness of treatment as per guidelines by two ED physicians and one cardiologist. Results We identified 306 eligible cases (0.2% of all ED visits): mean age 73.9 years, male 66.0%, admitted 53.3%, died in ED 2.3%. Primary arrhythmias and secondary tachycardias were each 50.0% (95% CI 44.4-55.6%). ED physicians correctly interpreted 81.2% of ECGs. The most common presenting arrythmias and % correct were: atrial fibrillation 42.7% (95.0%), atrial flutter 22.2% (63.5%), sinus tachycardia 12.0% (78.6%), and supraventricular tachycardia (SVT) 11.1% (68.0%). Treatments were judged optimal in 84.3% of primary WCT and 86.9% in secondary WCT. Treatments were suboptimal for: inappropriate drug (3.9% for primary versus 1.3% for secondary), failure to reduce heart rate < 100 prior to discharge home (9.1% for primary versus 34.4% for secondary), and not treating the underlying cause in 5.9% of secondary WCT. Conclusions WCT cases were evenly split between primary arrhythmias and secondary cases. ED physicians interpreted the ECG correctly in 81% but over-called atrial flutter and SVT. They implemented appropriate care in most cases but sometimes failed to adequately control heart rate or to treat the underlying condition, suggesting opportunities to improve care of WCT in the ED.