Ventricular bigeminy associated with voriconazole, methadone and esomeprazole

Concomitant Treatment with Proton Pump Inhibitors and Cephalosporins Does Not Enhance QT-Associated Proarrhythmia in Isolated Rabbit Hearts

Recent results from data mining analyses and reports of adverse drug events suggest a QT-prolonging drug-drug interaction resulting from the combination of distinct proton pump inhibitors and cephalosporins. Therefore, this study aimed at investigating the effect of the suspected QT-prolonging combinations of lansoprazole + ceftriaxone and esomeprazole + cefazolin, respectively. 26 hearts of New Zealand White rabbits were retrogradely perfused and paced at different cycle lengths. After generating baseline data, the hearts were assigned to two groups: In group 1, hearts were treated with 5 µM lansoprazole. Thereafter, 200 µM ceftriaxone was infused additionally. Group 2 was perfused with 10 µM esomeprazole followed by 250 µM cefazolin. In group 1, lansoprazole did not significantly alter QT intervals and APD₉₀. Additional treatment with ceftriaxone significantly shortened QT interval, APD₉₀ and slightly reduced dispersion of repolarization compared to sole lansoprazole infusion. In group 2, esomeprazole led to a significant shortening of the QT interval without altering APD₉₀ or dispersion. Additional treatment with the antibiotic cefazolin further shortened QT interval, APD₉₀ and reduced the dispersion of repolarization. Incidence of ventricular arrhythmias was not significantly altered in both groups. This is the first experimental whole-heart study that investigated the impact of a concomitant treatment with proton pump inhibitors and cephalosporins. In contrast to previous reports, the combination of both agents did not cause QT prolongation but instead shortened QT interval and action potential duration. As a consequence, no triggered activity occurred in the presence of a stable dispersion of repolarization.

Opioids and Cardiac Arrhythmia: A Literature Review

OBJECTIVE

One of the most important side effects of opioids is their influence on the electrical activity of the heart. This review focusses on the effects of opioids on QT interval prolongation and their arrhythmogenic liability.

METHODS

By using various keywords, papers published up to 2018 in different databases were searched and identified. The search terms were opioids names, corrected QT interval, human-ether-a-go-go gene, torsades de pointes (TdP), cardiac arrhythmias, opioid dependence and other relevant terms. It emphasized the effects of each opioid agent alone on electrocardiogram (ECG) and some interactions.

RESULTS

Available data indicate that some opioids such as methadone are high-risk even at low doses, and have potential for prolongation of the QT interval and development of TdP, a dangerous ventricular tachycardia. A number of opioids such as tramadol and oxycodone are intermediate risk drugs and may develop long QT interval and TdP in high doses. Some other opioids such as morphine and buprenorphine are low-risk drugs and do not produce QT interval prolongation and TdP at least in routine doses. Opium-consumers are at higher risk of supra-ventricular arrhythmias, sinus bradycardia, cardiac block and atrial fibrillation.

CONCLUSION

The cardiac arrhythmogenicity of various opioids is different. Methadone has a higher capability to induce long QT interval and dangerous arrhythmias in conventional doses than others. To reduce of arrhythmogenic risk, high doses of opioids must be used cautiously with periodic monitoring of ECG in high-risk consumers such as patients under opioid maintenance treatment.

A systematic review of the cardiotoxicity of methadone

Methadone is one of the most popular synthetic opioids in the world with some favorable properties making it useful both in the treatment of moderate to severe pain and for opioid addiction. Increased use of methadone has resulted in an increased prevalence of its toxicity, one aspect of which is cardiotoxicity. In this paper, we review the effects of methadone on the heart as well as cardiac concerns in some special situations such as pregnancy and childhood.

METHODS

We searched for the terms methadone, toxicity, poisoning, cardiotoxicity, heart, dysrhythmia, arrhythmia, QT interval prolongation, torsade de pointes, and Electrocardiogram (ECG) in bibliographical databases including TUMS digital library, PubMed, Scopus, and Google Scholar. This review includes relevant articles published between 2000 and 2013. The main cardiac effects of methadone include prolongation of QT interval and torsade de pointes. Other effects include changes in QT dispersion, pathological U waves, Taku-Tsubo syndrome (stress cardiomyopathy), Brugada-like syndrome, and coronary artery diseases. The aim of this paper is to inform physicians and health care staff about these adverse effects. Effectiveness of methadone in the treatment of pain and addiction should be weighed against these adverse effects and physicians should consider the ways to lessen such undesirable effects. This article presents some recommendations to prevent heart toxicity in methadone users.