Asymptomatic Cardiac Arrhythmia in Systemic Sclerosis
Fatemah Baron, Rajneet Singh, Bernadette Lynch
Department of Rheumatology, University College Hospital Galway (UCHG)
Systemic sclerosis (SSc) is a chronic autoimmune disease characterised by excessive cutaneous and visceral fibrosis. SSc can present with protean manifestations and result in significant organ dysfunction. Cardiac involvement in SSc can virtually affect any structure and when symptomatic, it predicts a poor prognosis.
A 37 year male, smoker, with a background of hypertension presented with generalised arthralgia. Clinical examination was consistent with sclerodactyly, calcinosis and Raynaud’s phenomenon. Immunology workup was positive for antinuclear antibodies and anti-SCL70. Over a six month period, he developed diffuse skin thickening with a modified Rodnan skin score of 21/51. He described intermittent dysphagia, dyspnea, worsening of Raynaud’s phenomenon and digital ulceration. Pulmonary function test suggested a restrictive pattern with a reduced DLCO 56%. He was admitted for an intravenous prostacyclin to treat active digital ulcers. During routine observation, he was found to have asymptomatic tachycardia. Electrocardiogram showed atrial flutter at a rate of 150 bpm with an elevated troponin T and pro-BNP. Subsequently, he developed supraventricular tachycardia (SVT) at a rate of 200 bpm, he was normotensive and asymptomatic. Patient failed both pharmacological and electrical cardioversion.
Echocardiogram showed extensive wall akinesia and ejection fraction 40%, suggestive of severe cardiomyopathy. Right and left heart catheterisation showed normal coronary structure and no evidence of pulmonary hypertension. Cardiac gadolinium MRI confirmed myocardial fibrosis, significant bi-ventricular impairment, global myocardial oedema, left ventricular ejection fraction (LVEF) 33% and right ventricular EF (RVEF) 24%. This is suggestive of cardiac scleroderma. He was commenced on anti-arrhythmic and life-long anticoagulation. An implantable cardioverter defibrillator was inserted for primary prevention of ventricular arrhythmia and sudden death. He was pulsed with three grammes of intravenous methylprednisolone followed by tapering oral prednisolone and monthly intravenous cyclophosphamide (0.5g/m2).
The majority of patients with cardiac involvement remain subclinical. To successfully manage cardiac scleroderma, it requires a high index of suspicion and a multidisciplinary approach. To the best of our knowledge, no RCTs have compared efficacy of anti-arrhythmic drugs to treat conduction abnormalities in SSc cohort. Thus, medication selection is tailored to the individual patient.