Hospital admissions to exclude myocardial ischemia as one possible cause of unexplained chest pain (CP) are costly and have a low positive diagnostic yield. This prospective study was performed to determine whether a comprehensive emergency department (ED)-based cardiology service provides accurate diagnoses with a significant cost savings. A special cardiology service providing consultations, exercise testing and echocardiography was used to evaluate 97 consecutive emergency department patients (pts) (44 male, 53 female) who presented with CP. The pts had one or more risk factors for coronary artery disease, a suspicious but atypical CP pattern, and no ECG/enzyme evidence of acute myocardial injury. To qualify, each pt had to be considered an appropriate candidate for hospital admission to evaluate CP by the ED physician. Based on negative exercise testing results performed upon clinical evaluation in the ED, all pts were discharged to continued non-cardiac ambulatory work-up. Mean cost of the evaluation was $ 1683 ± $871. A control group of 36 pts with similar symptoms underwent identical diagnostic procedures on an in-patient basis. In all cases, myocardial ischemia origin of the CP was excluded and the pts were discharged to various out-patient services. The mean cost of their hospital stay was $ 6358 ± $1884. We conclude that comprehensive cardiology service within an emergency department is a reliable alternative to hospitalization and results in a 74% cost-reduction for evaluation of a pt with atypical chest pain

Atrioventricular (AV) nodal reentrant tachycardia and atrial flutter are considered 2 distinct supraventricular tachycardias. Recent clinical and experimental data suggest that both these tachycardias include an area in the lower right atrial septum in their reentrant pathways. This study was designed to test the hypothesis that there is an association between the mechanisms of AV nodal reentrant tachycardia and atrial flutter because of a shared pathway of reentry. Consecutive patients referred for evaluation and management of supraventricular tachycardia, thought to be due to AV nodal reentry, underwent electrophysiologic testing protocols designed to induce both AV nodal reentrant tachycardia and atrial flutter, if present. Fifteen of 29 patients (52%) had both AV nodal reentrant tachycardia and atrial flutter induced during electrophysiologic testing. Seven of these 15 patients (47%) underwent transcatheter radiofrequency current application (mean power 34 +/- 4 W) against the tricuspid annulus above the coronary sinus. In each patient, neither '' nodal reentrant tachycardia nor atrial flutter could be induced after the procedure. Repeat study after successful ablation (mean 6 days) showed no inducible supraventricular arrhythmia of either type at baseline study or during isoproterenol infusion.Atrial flutter occurs frequently (15 of 29 patients; 52%) in patients with AV nodal reentrant tachycardia, because of a shared pathway in their reentry circuits. Because of this shared pathway, both arrhythmias can be ablated at the same site. These observations promote new insights into the mechanism and therapeutics of supraventricular tachycardias.