A Case of Chloroquine-Induced Cardiomyopathy That Presented as Sick Sinus Syndrome

Abstract

A 52-year-old woman with rheumatoid arthritis who had been treated with prednisone and hydroxychloroquine for >12 years presented with chest discomfort and a seizure. She was diagnosed with restrictive cardiomyopathy combined with sick sinus syndrome. A myocardial muscle biopsy was performed to identify the underlying cardiomyopathy, which showed marked muscle fiber hypertrophy, fiber dropout, slightly increased interstitial fibrous connective tissue, and extensive cytoplasmic vacuolization of the myocytes under light microscopy. Electron microscopy of the myocytes demonstrated dense, myeloid, and curvilinear bodies. The diagnosis of hydroxychloroquine-induced cardiomyopathy was made based on the clinical, hemodynamic, and pathologic findings. This is the first case report describing chloroquine-induced cardiomyopathy involving the heart conduction system.

Hydroxychloroquine cardiotoxicity presenting as a rapidly evolving biventricular cardiomyopathy: key diagnostic features and literature review

“…11 One patient presented with a generalized tonic-clonic seizure in the setting of sinus arrest. 16 In-hospital ventricular arrhythmias in the setting of a prolonged QT interval have been described; 18,21 in both cases, QT interval shortened following discontinuation of the drug.…”

“…[4][5][6][7][9][10][11][12][13][14][16][17][18][19][20] The most frequent presenting symptoms relate to decompensated left or biventricular failure as illustrated above. However, also as in our case, non-specific chest discomfort may be a presenting or co-existent feature 12,14,16 as can presyncope associated with conduction disease 12,14 or atrial arrhythmias. 11 One patient presented with a generalized tonic-clonic seizure in the setting of sinus arrest.…”

“…22,23 Prognosis in antimalarial cardiotoxicity can vary from death to cardiac transplantation to partial or complete improvement in cardiac function. 5,7,8,10,11,[13][14][15][16][17][18][19][20][24][25][26] Two case reports have described successful orthotopic heart transplantation. 7,10 Indication in both cases was refractory congestive heart failure 3 months after drug discontinuation.…”

“…14 To our knowledge, only four other cases of biopsy-proven HCQ cardiotoxicity in patients with isolated RA have been reported. 5,16,19 We present an additional case in a 52-year-old female with a history of connective tissue disease and venous thromboembolism presenting with refractory New York Heart Association (NYHA) functional class 2-3 dyspnoea and intermittent chest pain over a 2-year period in association with recurrent biomarker elevations, conduction system disease on 12-lead electrocardiograph (ECG), and rapidly evolving non-ischaemic pattern biventricular dysfunction.…”

“…To date, up to 70 cases of cardiotoxicity have been reported in the literature, although less than half of these have been proven on endomyocardial biopsy. In the past, CQ has been predominantly implicated, [4][5][6][7][8][9][10] but more recently several reports of HCQ-induced cardiomyopathy have emerged, 5,[11][12][13][14][15][16][17][18][19][20] likely reflecting its increased prevalence of use. Reported cases have occurred predominantly in SLE including discoid lupus rather than RA; more recently, a case has also been reported in scleroderma.…”