Diagnostic patterns and temporal trends in the evaluation of adult patients hospitalized with syncope.

BACKGROUND: Syncope is a common clinical problem that is often difficult and expensive to diagnose. We examined diagnostic patterns and trends and use of specialty consultations in the evaluation of syncope. METHODS: We retrospectively reviewed the medical records of consecutive adult patients hospitalized with the principal diagnosis of syncope (International Classification of Diseases, Ninth Revision, code 780.2) during 1994 and 1998 at 2 community teaching hospitals. RESULTS: A total of 649 patients (57% female) with a mean (+/-SD) age of 68 +/- 15 years were identified in 1994 (n = 451) and 1998 (n = 198). Three hundred forty-one patients (53%) underwent at least 1 neurologic test, including brain computed tomographic (CT) scan (n = 283), electroencephalography (n = 253), carotid Doppler echocardiography (n = 185), and brain magnetic resonance imaging (n = 10). Only brain CT scan and electroencephalography yielded diagnoses in 5 (2%) and 6 patients (2%), respectively with history consistent with seizures or stroke. Cardiovascular tests providing the highest diagnostic yields (postural blood pressure check in 52 [30%], head-up tilt-table test in 32 [24%], and electrophysiologic study in 5 [16%]) were used in 176 (27%), 132 (20%), and 31 patients (5%), respectively. Differences in the use of some tests were noted at the participating hospitals and over time (1994 vs 1998). The total number of diagnosed cases was similar for patients undergoing evaluation by primary care physicians alone (65/103 [63%]), compared with cardiology (48/85 [56%]), neurology (29/48 [60%]), or both (81/141 [57%]). After a mean (+/-SD) length of stay of 5 +/- 4 days, 320 (49%) of 649 cases remained undiagnosed. CONCLUSIONS: Despite a reduction in the use of some tests (eg, brain CT scan and carotid Doppler) over time, lower-yield neurologic tests were overused and higher-yield cardiovascular tests were likely underused. The untargeted, seemingly random use of specialty evaluations did not seem to contribute to an increase in the overall number of diagnosed cases. Increased use of specific tests directed by history and results of physical examination may improve diagnostic yield and decrease the cost of evaluating syncope.

Sudden death in recipients of transvenous implantable cardioverter defibrillator systems: terminal events, predictors, and potential mechanisms.

INTRODUCTION: Transvenous implantable cardioverter defibrillator (ICD) systems are very effective in preventing sudden death; however, little is known about terminal events and potential causes and mechanisms of sudden death in recipients of these devices. METHODS AND RESULTS: We analyzed 74 cases of sudden death among patients enrolled in several clinical investigations of transvenous ICD systems. Eighty-one percent were men (mean age 68+/-10 years), 86% had coronary artery disease, mean left ventricular ejection fraction was 0.27+/-0.11, and two thirds presented with sustained ventricular tachycardia. The final event was witnessed in 65 patients (81%). Based on reported ICD shocks, documented rhythm, and/or postmortem device data, sudden death was deemed tachyarrhythmic in 49 cases (66%), nontachyarrhythmic in 12 (16%), and indeterminate in the remaining 13 (18%). Multivariate analysis of several clinical and nonclinical factors found advanced age (> 65 years, P = 0.03, odds ratio [OR] 1.75, 95 % confidence interval [CI] 1.05 to 2.92), reduced left ventricular ejection fraction (< 0.35, P < 0.01, OR 3.51, CI 1.66 to 7.40), and having antibradycardia pacing ICDs (P = 0.02, OR 5.26, CI 1.37 to 20.0) to be independent predictors of sudden death. One or more predisposing factors and/or potential causes of sudden death were identified in 21 patients (28%). CONCLUSION: In this select group of transvenous ICD recipients, (1) sudden death was associated with ventricular tachycardia/ventricular fibrillation in at least two thirds of cases, (2) nearly one third of patients had one or more factors, some device related, that could have been associated with sudden death, and (3) death ensued despite appropriate ICD therapies and, in many cases, external resuscitation, suggesting acute adverse events as common terminal factors.