The Cardiac Safety of Chloroquine Phosphate Treatment in Patients with Systemic Lupus Erythematosus: The Influence on Arrhythmia, Heart Rate Variability and Repolarization Parameters

Abstract

Antimalarials are used to treat cutaneous and systemic lupus erythematosus (SLE). Even though cardiac damage is a rare complication, over the last decade several reports have raised the issue of cardiotoxicity associated with antimalarials. Therefore, the aim of study was to evaluate the influence of seven-month chloroquine treatment with a 250mg daily dose on arrhythmia, conduction disturbances as well as heart rate variability and repolarization parameters assessed in 24-hour Holter monitoring. The studied group included 28 SLE patients treated with chloroquine as a monotherapy. In all the patients standard 12 leads surface ECG (50 mm) and the 24-hour ECG Holter monitoring (Oxford Medilog Excel-2) were performed before and after chloroquine phosphate treatment. All subjects presented sinus rhythm both at the enrollment and after treatment. No episodes of paroxysmal arrhythmias or conduction disturbances were reported during the study. All the patients were characterized by tendency to tachycardia, but no significant differences in mean heart rate were found before and after chloroquine administration. Similarly, no changes in heart rate variability or repolarization parameters were observed.

Clinical efficacy and side effects of antimalarials in systemic lupus erythematosus: a systematic review

“…Cardiotoxicity of AMs in patients with SLE has been evaluated in 2 studies66 67 including 70 patients treated with HCQ and 28 patients treated with CQ, respectively. No cases of clinically relevant cardiotoxicity were reported.…”

Chloroquine Prevents Progression of Experimental Pulmonary Hypertension via Inhibition of Autophagy and Lysosomal Bone Morphogenetic Protein Type II Receptor Degradation

“…40 There are case reports of aminoquinolones causing cardiomyopathy and arrhythmia after acute administration of high doses, but in the chronic treatment of autoimmune disease this is not observed. 41 Our measurements from animals exposed to 50 mg/kg of chloroquine for up to 3 weeks did not reveal any signs of cardiac dysfunction. Indeed, in monocrotaline-exposed animals, chloroquine improved cardiac output and other indices of cardiac function.…”

Cumulative dose of hydroxychloroquine is associated with a decrease of resting heart rate in patients with systemic lupus erythematosus: a pilot study

“…Most of the earlier evidence refers to the results obtained with chloroquine. [5][6][7] In our work, the significant decrease in RHR associated with high CD-HCQ could be related either with the prolongation of atrial refractory period seen with the use of stereoisomers from quinidine Cumulative dose of HCQ is associated with a decrease of RHR in patients with SLE: a pilot study E Cairoli et al or with the cardiotoxicity associated with the use of antimalarials. 5,6 This decrease, however, could exert a cardioprotective effect, based in the decrease of miocardic oxygen consumption as was originally described for beta-blockers, therefore it could be assigned a direct cardioprotective property of high CD-HCQ, describing a similar beta-blocker function (beta-blocker-like effect).…”