(150) Through Thick and Thin: A Rare Case of Left Ventricle Noncompaction Cardiomyopathy

Introduction: Left ventricular noncompaction cardiomyopathy (LVNC) is a rare congenital cardiomyopathy characterized by an altered left ventricular myocardial wall consisting of a thick endocardial layer, with prominent trabeculations and recesses, alongside a thin epicardial layer. The disease is seen in 0.001% to 0.3% of adults.

Description: A 20-year-old male with no past medical history presented to the emergency room with four days of new onset dyspnea, chest pain, and dry cough. He had no prior history of similar symptoms. Relevant family history included paternal left ventricle (LV) thickening of unknown etiology. Exam revealed tachycardia and bilateral crackles; he had no leg edema or JVD. Labs were significant for BNP 1112 and mildly elevated troponin. A transthoracic echocardiogram (TTE) revealed a left ventricle ejection fraction (LVEF) of 20% and small LV crypts suspicious for LVNC. Cardiac catheterization revealed normal coronary arteries. He was managed with furosemide, metoprolol succinate, spironolactone and losartan. A subsequent cardiac MRI revealed LVNC with LVEF of 13% and an apical LV thrombus; rivaroxaban was started. He was discharged on empagliflozin and was given a life vest. Currently, he continues to have recurrent hospitalizations due to heart failure exacerbations and is currently scheduled to receive a cardiac transplant.

Discussion: The most common LVNC manifestations include dyspnea, palpitations, chest pain, and syncope. LVNC complications include heart failure, thromboembolism, and arrhythmias. LVNC has been linked to genetic mutations in sarcomeric protein genes, tafazzin gene, and alpha-dystrobrevin gene. Diagnosing LVNC involves finding morphologic diagnostic criteria, most commonly via TTE. If the diagnosis remains uncertain, further imaging with cardiac MRI or CT can be used. Treatment involves medical management of heart failure and possible cardiac transplant. LVNC carries a poor prognosis with some medical literature estimating an overall mortality rate of 14% in 39 months, half of which are due to sudden cardiac arrest. Due to its high mortality rates, physicians should keep LVNC in their differential for young patients presenting with sudden onset of dyspnea and chest pain.