Cardiac Sarcoidosis, Left Ventricular Impairment and Chronic Right Ventricular Pacing: Pacing or Pathology?

Background: Cardiac sarcoidosis (CS) is an uncommon and under-recognised disease which most frequently presents with atrioventricular (AV) block and may also present with ventricular arrhythmias and left ventricular (LV) systolic dysfunction. Because of its protean clinical manifestations, confirming a diagnosis of CS is often challenging.

Methods: We report two cases where patients presented with atrioventricular (AV) block without evidence of underlying myocardial disease, underwent chronic dual-chamber pacing, and presented several years later with severe LV systolic dysfunction.

Results: Both patients were referred for assessment of pacing-induced cardiomyopathy with a view to upgrading their device to cardiac resynchronisation therapy (CRT). Subsequent investigation revealed features consistent with CS and appropriate immunosuppressive therapy resulted in improvement in LV function avoiding the requirement for CRT.

Conclusion: We present a review of the diagnosis of cardiac sarcoidosis, the importance of imaging modalities and current treatment recommendations.