Doxorubicin-induced second degree and complete atrioventricular block

Abstract

Doxorubicin is one of the most effective chemotherapeutic agents used in the treatment of malignancies. Cardiotoxicity is the most important dose-limiting toxicity of doxorubicin. Although cardiomyopathy is the most well known side effect of doxorubicin, it usually occurs many years after the treatment and relates to cumulative doxorubicin dosage. Another form of doxorubicin cardiotoxicity is arrhythmia which may occur at any time and after any dosage. However, doxorubicin-induced arrhythmia is rarely a life-threatening side effect. In this report, we present a case in which there were doxorubicin-induced life-threatening arrhythmias.

Long-term Cardiovascular Toxicity in Children, Adolescents, and Young Adults Who Receive Cancer Therapy: Pathophysiology, Course, Monitoring, Management, Prevention, and Research Directions

“…Cumulative toxicity is generally a result In most instances, arrhythmias associated with anthracyclines are transient and do not require specific intervention. However, Kilickap et al 58 reported serious consequences in a patient with syncope and complete heart block who required pacemaker implantation during anthracycline therapy at only modest doses (cumulative dose of 120 mg/m 2 ). This response has also been described for epirubicin, which is thought to have a more favorable cardiovascular toxicity profile.…”

“…The incidence of these findings ranges from 10% to 30%. 55,57,58 The mechanism of the electrophysiological cardiotoxicity is unknown, although the efficacy of dexrazoxane in attenuating this injury suggests that the toxicity may be mediated through free radicals. Acute changes that occur during infusion therapy range from fatal ventricular arrhythmias to minor abnormalities.…”

Ventricular Repolarization Intervals in Children Previously Treated with Anthracyclines

“…More recent studies have reinforced the association between anthracycline and prolonged corrected QT (QTc) intervals as measured on surface the surface electrocardiogram, which may point to heightened risk of ventricular tachycardia [12,13] Anthracyclines have been directly associated with premature ventricular contractions, sinus node dysfunction, ventricular late potentials, and decreased QRS voltage. The incidence of such occurrence ranges from 10% to 30% [14,15]. The mechanism and the structural characteristics of drugs most likely to alter the duration of the QT interval have been determined.…”

In vivo antitumor potential of extracts from different parts of Bauhinia variegata linn. Against b16f10 melanoma tumour model in c57bl/6 mice

“…For example, 5-fluorouracil, a common chemotherapeutic agent, is known to cause myelotoxicity [3], cardiotoxicity [4] and has even been shown to act as a vasospastic agent in rare but documented cases [5]. Another widely used chemodrug, doxorubicin causes cardiac toxicity [6][7][8], renal toxicity [9], and myelotoxicity. [10] Similarly, bleomycin a well-known chemotherapeutic agent, is known for its pulmonary toxicity [11][12][13].…”