Influence of Interferon Therapy on Signal-Averaged and Ambulatory Electrocardiograms in Patients With Chronic Active Hepatitis

Abstract

SUMMARYAlthough interferon (IFN) shows cardiotoxicity and arrhythmogenesis, the influence of IFN on signal-averaged electrocardiography remains to be clarified. The aim of this study was to test a clinical hypothesis that IFN therapy for hepatitis C virus may induce ventricular late potentials (LPs) and related arrhythmias in patients with chronic active hepatitis. Signal-averaged and ambulatory electrocardiograms were recorded sequentially in patients with chronic active hepatitis C (n = 22) throughout the entire period of IFN therapy. The filtered QRS duration (fQRS) and low amplitude (< 40 µV) signal duration (LAS40) were significantly increased (95.5 ± 8.5 to 99.6 ± 9.4 msec, P < 0.0001, and 32.8 ± 3.1 to 36.3 ± 3.0 msec, P < 0.0001, respectively), whereas the root mean square voltage in the terminal 40 msec of the fQRS (RMS40) was significantly decreased (25.5 ± 5.4 to 22.3 ± 5.2 µV, P < 0.005) 1 month after starting the IFN therapy. The ventricular LP was negative in all subjects before starting therapy, but became positive in 7 patients after the therapy commenced. There were no differences in clinical baseline characteristics between the LP-positive (n = 7) and LP-negative (n = 15) groups. Significant increases in mean heart rate, fQRS, and LAS40 were observed after starting the therapy, irrespective of the appearance of the ventricular LP, whereas a decrease in RMS40 was observed only in the LP-positive group. No sustained ventricular arrhythmias were documented in the ambulatory electrocardiography and no cardiac events were encountered in the followup period. Therefore, the results indicate a reversible and subclinical risk of IFN-induced arrhythmogenesis. (Int Heart J 2005; 46: 1033-1040

Cardiovascular risk assessment by electrocardiographic Holter monitoring in patients with chronic hepatitis C

“…Hiramatsu et al . [ 33 ] demonstrated in a group of 22 subjects a transient growth of late potentials and disturbance of their parameters in the course of hepatitis C therapy with interferon. However, it did not result in a higher incidence of dangerous ventricular arrhythmia.…”

Is Combination Therapy for Chronic Hepatitis C Toxic for Cardiac Function?

“…Pegylated interferon (Peg-IFN) in combination with ribavirin therapy is currently the first-line treatment option for chronic hepatitis C. This regimen can achieve sustained virological response, in more than 50% of chronic hepatitis C patients (14). On the other hand, interferon is also known to induce adverse cardiac effects such as ventricular LPs in patients with chronic active hepatitis (15). Interferon can also cause; flu-like symptoms, hypotension or hypertension, and tachycardia after treatment (16).…”

Cardiac arrhythmia induced by interferon beta‐1a

“…For instance, PKC activation inhibits both cardiac Na and Ca channels by phosphorylating specific sites in certain domains of channel subunits. The dual suppression of Na and Ca channels by PKC may accelerate the ventricular slow conduction and may underlie ventricular late potentials observed under IFN therapy [11].…”