Should Complex Ventricular Arrhythmias Patients with Congestive Heart Failure Treated? A Protagonist% Viewpoint
in Be
Jeffrey L. Anderson, MD he prognosis in congestive heart failure (CHF) is poor. About 50% of patients die within 5 years and almost one-half of these deaths are sudden.‘,2 Thus, prophylactic management strategies are needed.
T
na or dyspnea is present. Digitalis is reserved for atria1 fibrillation or a low-output syndrome with a dilated heart and a ventricular gallop. ARRHYTHMOGENIC
EFFFCTS
OF CONGESTIVE
HEART
I-AIL-
The treatment of CHF may itself be arimportance of complex ventricular arrhythmias in rhythmogenic. Diuretics frequently cause electrolyte imbalance. Digitalis may cause toxic arrhythmias. Othcongestive heart failure: High-grade, complex ventricular arrhythmias occur in most patients with a history of er inotropes, including the new vasodilator-inotropes, CHF and are associatedwith an increasedrisk of mor- have proarrhythmic risk and may worsen long-term tality, particularly sudden death. In 1 review,’ couplets progn0sis.s Direct-acting vasodilators cause reflex inand/or multiformed complexes occurred in 87% of pa- creasesin sympathetic tone and renin release,predispostients and runs of ventricular tachycardia occurred in ing to ventricular arrhythmias. An important goal is 54% of CHF patients. In another review, unsustained to prevent, minimize or reverse these arrhythmogenic ventricular tachycardia increased the risk of mortality effects. CONVERTING-ENZYME IYIIIB1TION AllD ARRHYTIIMIAS: by a factor of 2.8 (range, 1.3 to .5.4).2 The risk of arrhythmias on mortality is also independent of ejection Arrhythmia decreaseis among the effects of convertingfraction.3m5Besidesambient arrhythmias,3,4 arrhythmia enzyme therapy. Captopril has been shown to decrease inducibility at electrophysiologic study is a strong risk ventricular ectopic frequency by one-third and to supmarker for mortality5 and may be a better guide to pressruns by two-thirds.’ These effects were associated therapy than ambulatory monitoring.6 The presenceof with decreasesin plasma norepinephrine and increases a late potential on signal-averaged electrocardiography in potassium levels to well within the therapeutic range. also causesan increased risk of ventricular tachyar- A beneficial effect of converting-enzyme inhibition on rhythmias and sudden death and this risk is greater mortality has also recently been shown. In the Cooperathan and independent of the presence of spontaneous tive North Scandinavian Enalapril Survival Study of arrhythmia.’ enalapril versus placebo in 253 patients with class IV Therapy other than traditional antiarrhythmic CHF, treatment decreased mortality by 41% at 6 drugs: MULTIPLE RISK FACTORS: If complex ventricular months (p
in Be
Jeffrey L. Anderson, MD he prognosis in congestive heart failure (CHF) is poor. About 50% of patients die within 5 years and almost one-half of these deaths are sudden.‘,2 Thus, prophylactic management strategies are needed.
T
na or dyspnea is present. Digitalis is reserved for atria1 fibrillation or a low-output syndrome with a dilated heart and a ventricular gallop. ARRHYTHMOGENIC
EFFFCTS
OF CONGESTIVE
HEART
I-AIL-
The treatment of CHF may itself be arimportance of complex ventricular arrhythmias in rhythmogenic. Diuretics frequently cause electrolyte imbalance. Digitalis may cause toxic arrhythmias. Othcongestive heart failure: High-grade, complex ventricular arrhythmias occur in most patients with a history of er inotropes, including the new vasodilator-inotropes, CHF and are associatedwith an increasedrisk of mor- have proarrhythmic risk and may worsen long-term tality, particularly sudden death. In 1 review,’ couplets progn0sis.s Direct-acting vasodilators cause reflex inand/or multiformed complexes occurred in 87% of pa- creasesin sympathetic tone and renin release,predispostients and runs of ventricular tachycardia occurred in ing to ventricular arrhythmias. An important goal is 54% of CHF patients. In another review, unsustained to prevent, minimize or reverse these arrhythmogenic ventricular tachycardia increased the risk of mortality effects. CONVERTING-ENZYME IYIIIB1TION AllD ARRHYTIIMIAS: by a factor of 2.8 (range, 1.3 to .5.4).2 The risk of arrhythmias on mortality is also independent of ejection Arrhythmia decreaseis among the effects of convertingfraction.3m5Besidesambient arrhythmias,3,4 arrhythmia enzyme therapy. Captopril has been shown to decrease inducibility at electrophysiologic study is a strong risk ventricular ectopic frequency by one-third and to supmarker for mortality5 and may be a better guide to pressruns by two-thirds.’ These effects were associated therapy than ambulatory monitoring.6 The presenceof with decreasesin plasma norepinephrine and increases a late potential on signal-averaged electrocardiography in potassium levels to well within the therapeutic range. also causesan increased risk of ventricular tachyar- A beneficial effect of converting-enzyme inhibition on rhythmias and sudden death and this risk is greater mortality has also recently been shown. In the Cooperathan and independent of the presence of spontaneous tive North Scandinavian Enalapril Survival Study of arrhythmia.’ enalapril versus placebo in 253 patients with class IV Therapy other than traditional antiarrhythmic CHF, treatment decreased mortality by 41% at 6 drugs: MULTIPLE RISK FACTORS: If complex ventricular months (p
