Abstracts

Abstracts in this issue were

prepared by residents in the

Denver General Emergency

Medicine Residency Program.

Samuel M Keim, MD

Co-Editor

Section of Emergency Medicine

University of Arizona College

of Medicine

Tucson, Arizona

Laurie Vande Krol, MD

Co-Editor

Emergency Medical Services

Denver General Hospital

Denver, Colorado

William A Robinson, MD, FACEP

Co-Editor

Department of Emergency

Medicine

University of Missouri-Kansas City

School of Medicine

Kansas City, Missouri

congestive heart failure; enalaprilat

Hemodynamic response to intravenous enalaprilat in patients with severe congestive heart failure and mitral regurgitation Varriale P, David W, Chryssos BE Clin Cardiol 16.235-238 Mar 1993

A prospective study of 20 patients with severe congestive heart failure associated with mitral regurgitation was undertaken to determine if a newly introduced IV angiotensin converting enzyme inhibitor (IV enalaprilat) is effective treatment of congestive heart failure. These patients had severe, chronic conges- tive heart failure (New York Heart Association functional class IV) and were referred for hemodynamic evaluation. Art had symptoms and signs of advanced left ventricular dysfunction and moderate-to-severe mitral regurgitation by color Doppler echocardiography. Patients were classified into two groups based on the magnitude of mitral regurgita- tion. Group 1 patients (13) had severe mitral regurgitation, and group 2 patients (seven) had moder- ate mitrat regurgitation. All previous cardiac medications were discon- tinued for 24 or more hours before

invasive hemedynamic studies. Baseline hemodynamic measure- ments were obtained on all patients; then, each patient received 1.25 mg enalaprilat IV over five minutes. Repeat hemodynamic measurements and Doppler color flow imaging studies were obtained after one hour. For group 1 patients, signifi- cant (P< .05) improvements were seen in systemic vascular resistance index, cardiac index, stroke volume index, purmonary capillary wedge pressure, mean arterial pressure, and heart rate. There was an insignificant decrine in mean right atrial pressure. In group 2 patients, significant improvements were seen in systemic vascular resistance index, pulmonary capillary wedge pressure, and mean arterial pres- sure. There were nonsignificant improvements in cardiac and stroke volume indices, heart rate, and mean and right atrial pressures. Four patients had transient (five to 15 minutes) asymptomatic systolic hypotension that did not require supportive therapy. The authors conclude that their findings support the use of IV enalaprilat as an effec- tive and rapidly acting parenteral agent in the management of select- ed patients with advanced chronic heart failure and mitral regurgitation who require immediate hemodynamic improvement. [Editor's note: These data are encouraging for the use of IV enataprilat as another option in the acute management of congestive heart failure and suggest that it may be more effective in severe cases. A clinical trial in patients

with acute exacerbations of congestive heart failure could demonstrate the value of this drug in emergency medicine.]

Brent Jones, MD

carbon monoxide; arrhythmia

Effects of carbon monoxide exposure in patients with documented cardiac arrhythmias Oahms TE, Younis L T, Wiens RD, et al

J Am Cell Cardiol 21.442-450 Feb 1993

This prospective study assessed whether carbon monoxide exposure resulting in 3% and 5% blood car- boxyhemoglobin levels affected ventricular arrhythmia frequency at rest or during or after exercise. A total of 30 nonsmoking patients with ischemic heart disease and chronic ventficular arrhythmias (defined as 30 or more premature ventricular complexes per hour} were studied. Exclusion.criteria included recent angina at rest, severe uncontrolled hypertension, decompensated con- gestive heart failure, claudication, left bundle branch block, or homo- dynamically significant ventficular arrhythmias. Subjects were exposed on three separate days of testing to

o room air, 3 Yo carboxyhemoglobin,

JULY 1993 22:7 ANNALS OF EMERGENCY MEDICINE 1 2 4 1 / 1 6 9