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Differences in mechanisms and outcomes of syncope in patients with coronary disease or idiopathic left ventricular

Béatrice Brembilla-Perrot1, Christine Suty-Selton, Daniel Beurrier

  • 1Department of Cardiology, CHU of Brabois, Vandoeuvre Les Nancy, France. b.brembilla-perrot@chu-nancy.fr

Journal of the American College of Cardiology
|September 11, 2004
PubMed

Insights

Syncope causes in heart disease differ: ventricular tachycardia is common in coronary disease, while left ventricular ejection fraction predicts prognosis in dilated cardiomyopathy. This impacts automated defibrillator use.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Heart Failure Research

Background:

  • Risk stratification and automated defibrillator indications may vary based on the underlying cause of left ventricular (LV) dysfunction.
  • Understanding these differences is crucial for patient management and device selection.

Purpose of the Study:

  • To evaluate the causes of syncope in patients with left ventricular dysfunction.
  • To compare the significance and differences in syncope causes between coronary disease and idiopathic dilated cardiomyopathy (DCM).

Main Methods:

  • Electrophysiologic studies, including programmed atrial and ventricular stimulation, were conducted in 119 patients with coronary disease and 61 with DCM (LV ejection fraction <40%) presenting with syncope.
  • Patients were followed for 1-6 years.

Main Results:

  • Sustained ventricular tachycardia (VT) or ventricular fibrillation (VF) was induced in a significant proportion of patients, particularly in the coronary disease group.
  • Syncope remained unexplained in approximately 30% of patients in both groups.
  • Prognosis was linked to the heart condition: VT/VF induction predicted mortality in coronary disease, whereas cardiac mortality in DCM correlated solely with LV ejection fraction.

Conclusions:

  • Syncope causes in coronary disease and DCM are diverse, with distinct patterns observed.
  • Ventricular tachycardia is a frequent finding in coronary disease, associated with a poorer prognosis and potentially linked to ischemia.
  • In DCM, while other arrhythmias like atrial tachycardia can cause syncope, prognosis is primarily determined by left ventricular ejection fraction.
Abstract

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