Prevalence and significance of nonsustained ventricular tachycardia in patients with premature ventricular contractions and heart failure treated with vasodilator therapy. Department of Veterans Affairs CHF STAT Investigators.
OBJECTIVE
This study sought to determine the prevalence and significance of nonsustained ventricular tachycardia (NSVT) in patients with premature ventricular contractions (PVCs) and heart failure treated with vasodilator therapy.


BACKGROUND
Heart failure patients with ventricular arrhythmia and NSVT have a significantly increased risk of premature cardiac death. Recently there has been the question of whether these arrhythmias are expressions of a severely compromised ventricle or are they independent risk factors. We, therefore, determined the prevalence and significance of NSVT in patients with PVCs and heart failure and on vasodilator therapy.


METHODS
Twenty-four hour ambulatory recordings were done at randomization, at 2 weeks, at months 1, 3, 6, 9 and 12 and then every 6 months in 674 patients with heart failure and on vasodilator therapy. The median period of follow-up was 45 months (range 0 to 54).


RESULTS
Nonsustained ventricular tachycardia was present in 80% of all patients. Patients without (group 1) and with (group 2) NSVT were balanced for variables: age, etiology of heart disease, New York Heart Association (NYHA) functional class, use of amiodarone and diuretics and left ventricular diameter by echocardiogram. However, group 1 patients had significantly less beta-adrenergic blocking agent use and higher ejection fraction (EF) (p < 0.002 and p < 0.001, respectively). Survival analysis for all deaths showed a greater risk of death among group 2 patients (p=0.01). Similarly, sudden death was increased in group 2 patients (p=0.02, risk ratio 1.8). After adjusting for the above variables, only EF (p=0.001) and NYHA class (p=0.01) were shown to be independent predictors of survival. Nonsustained ventricular tachycardia showed a trend (p=0.07) as an independent predictor for all-cause mortality but not for sudden death. Only EF was an independent predictor for sudden death.


CONCLUSIONS
Nonsustained ventricular tachycardia is frequently seen in patients with heart failure and may be associated with worsened survival by univariate analysis. However, after adjusting other variables, especially for EF, NSVT was not an independent predictor of all-cause mortality or sudden death. These results have serious implications in that suppression of these arrhythmias may not improve survival.
VA Medical Center, Washington, DC 20422, USA. snsingh@erols.com
S N
SN
Singh
S G
SG
Fisher
P E
PE
Carson
R D
RD
Fletcher
D000368:Aged; D000638:Amiodarone / Q000627:therapeutic use*; D016757:Death, Sudden, Cardiac / Q000209:etiology; D015716:Electrocardiography, Ambulatory; D006333:Heart Failure / Q000150:complications / Q000188:drug therapy* / Q000401:mortality; D006801:Humans; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors; D015996:Survival Rate; D017180:Tachycardia, Ventricular / Q000150:complications* / Q000175:diagnosis; D014665:Vasodilator Agents / Q000627:therapeutic use*; D018879:Ventricular Premature Complexes / Q000150:complications* / Q000175:diagnosis
D014665:Vasodilator Agents; D000638:Amiodarone