Worsening Heart Failure and Atrial Flutter in a Patient Secondary to Cardiac Resynchronization Therapy Dyssynchrony: A Case Report

Cardiac resynchronization therapy-defibrillator (CRT-D) and/or cardiac resynchronization therapy-pacemaker (CRT-P) play an important role in improving cardiac synchronization and reducing the risk of ventricular fibrillation arrest (VFA) in patients with severe left ventricular systolic dysfunction (LVSD). Patients with LVSD may notice worsening symptoms when CRT-D or CRT-P is in dyssynchrony. We present a case of 59-year-old patient who presented with worsening shortness of breath (SOB) and progressive exertional dyspnea for the past few weeks accompanied by pink, frothy sputum, occasional urinary incontinence and urge. He was known to have severe LVSD with an ejection fraction of 10% and had CRT-D in situ. Clinical examination revealed bilateral crepitation and normal heart sounds. A chest radiograph showed pulmonary oedema. An electrocardiogram (ECG) showed atrial fibrillation (AF)/flutter with wide QRS complexes. The patient was treated for acute pulmonary oedema and had CRT-D reprogrammed to achieve biventricular synchrony. He was treated with intravenous furosemide and alternate day metolazone initially. He showed significant subjective and objective improvement and was planned for outpatient synchronized intra-device cardioversion. This case is important because patients with severe LVSD with malfunctioning cardiac resynchronization therapy can result in worsening heart failure (HF) leading to higher morbidity and mortality.