RESUMEN
A 66-year-old female with end-stage renal disease and heart failure with reduced ejection fraction, status post implantable cardioverter defibrillator (ICD) presented to the emergency department with dizziness and fatigue. An electrocardiogram showed sinus rhythm, complete atrioventricular block, and ventricular paced rhythm at 30 beats per minute (bpm). Device interrogation revealed a programmed VVI mode with a lower rate limit of 40 bpm and evidence of T wave oversensing. Serologic studies were remarkable for hyperkalemia (7.9 mmol/dL). The device was initially reprogrammed to provide a higher pacing rate and symptomatic improvement. Both complete AV block and T wave oversensing resolved after correction of hyperkalemia. This case highlights the need for vigilant monitoring of electrolyte imbalances in ICD patients.
RESUMEN
Left ventricle non-compaction (LVNC) is a rare congenital cardiomyopathy characterized by thickened myocardium due to an arrest of the normal compaction of the embryonic sponge-like meshwork of myocardial fibers. We present a 40-year-old man with no known systemic illnesses admitted with cardiogenic shock and multiorgan failure. Echocardiogram revealed severe enlargement of all four chambers with left ventricular ejection fraction (LVEF) <10%. Cardiac magnetic resonance imaging (CMR) showed hypertrabecular left ventricular myocardium with a ratio of non-compact to compact myocardium of 2.3, diffuse myocardial thinning, and a 16-mm left ventricular thrombus. These findings were compatible with LVNC. The patient was treated with intravenous inotropic vasopressors for cardiogenic shock and enoxaparin as bridging for warfarin to a goal of INR 2.0-3.0. Due to refractory heart failure (HF) and dependency on inotropic support, the patient was placed on the waiting list for a heart transplant. Unfortunately, 27 days after admission, he presented ventricular tachycardia arrest and did not respond to aggressive advanced cardiac life support measures. A high index of suspicion is required for the early diagnosis, which in turn allows the physician to prevent complications of this condition. There is no specific therapy, so management is directed toward the clinical manifestations including HF, arrhythmias, and systemic embolic events. Heart transplantation is the only definitive treatment.