Ventricular late potentials: a critical overview and current applications.
BACKGROUND
More than 450 000 Americans die suddenly each year from sustained ventricular tachycardia (VT) or fibrillation. Overall, event rates in Europe are similar to those in the United States. A correct risk stratification is essential to reduce the incidence of sudden cardiac death. Ventricular late potentials (VLPs) represent delayed conduction through a diseased myocardium and consist of the presence of electrical activity after the end of the standard QRS. The VLPs are potential substrates for reentry VT.


METHODS
The VLPs were found highly predictive of cardiac events, in particular, arrhythmic events, in patients with acute myocardial infarction. The weakness of VLPs is the low positive predictive value, especially as a single technique. However, their negative predictive value for arrhythmic events is very high. The VLPs are observed in more than 50% of patients with arrhythmogenic right ventricular cardiomyopathy, and are actually considered a helpful diagnostic tool in this setting. In patients with syncope of unknown cause, VLP analysis, combined with patient history and other diagnostic tests, can help identify or exclude a mechanism of VT as a cause of the syncope.


CONCLUSIONS
The VLP assessment offers a practical and low-cost tool to the clinical cardiologist to recognize the possible electrophysiologic substrate underlying life-threatening ventricular arrhythmias. The strength of VLPs is their high negative predictive value. When positive, VLPs still help better stratify the arrhythmic risk of patients in several clinical settings.
Santangeli
Pasquale
P
Istituto di Cardiologia, Università Cattolica del Sacro Cuore, 00168 Roma, Italy. pasquale.santangeli@libero.it
Infusino
Fabio
F
Sgueglia
Gregory Angelo
GA
Sestito
Alfonso
A
Lanza
Gaetano Antonio
GA
D003937:Diagnosis, Differential; D004562:Electrocardiography / Q000379:methods*; D006801:Humans; D017180:Tachycardia, Ventricular / Q000175:diagnosis*; D014693:Ventricular Fibrillation / Q000175:diagnosis*