A 45‐year‐old woman presented with dyspnea on exertion, and tachycardia. On presentation, vitals were normal except for a resting heart rate of 100. Exam revealed tachycardia, trace pedal edema, and jugular venous pressure at 8 cm H2O. Lungs were clear. Chemistries and CBC were normal. Fasting lipid panel revealed cholesterol 289, triglycerides 537, HDL 53, and LDL 170. An EKG showed left atrial enlargement and left ventricular hypertrophy. Exercise MIBI showed no evidence of ischemia or infarction but did reveal dilation and diffuse severe hypokinesis of the left ventricle with an ejection fraction of 16%. Workup of this finding included TSH, HIV, ANA, SPEP, iron levels and ACE, all of which were all normal. CTA showed severe impairment of LV function, out of proportion to the nonobstructive coronary artery disease. The LV showed hypertrabeculation, with noncompacted myocardium measuring 2.1 cm and compacted myocardium measuring 0.8 cm at end diastole. A ratio ≥ 2:1 is consistent with LV noncompaction (LVNC) syndrome. A cardiac MRI confirmed this diagnosis. The patient began aspirin, atorvastatin, carvedilol, and lisinopril. She had ICD implantation and started long‐term anticoagulation.
Left ventricular noncompaction is caused by defective embryogenesis of the fetal myocardium. During development, the loose meshwork of fibers normally becomes compacted between weeks 5 and 8. However, when this fails to occur, hypertrabeculation of the left ventricle results. Clinically, LVNC usually presents as heart failure, arrhythmia, and thromboembolic events. The diagnosis is often achieved by echocardiography, although contrast ventriculography, MRI, and CT have been used. LVNC has a poor prognosis in adults. Management focuses on treating the 3 major clinical manifestations. In particular, aspirin, statin, ACE, beta‐blocker, and diuretics are used. In patients with reduced ejection fractions (<30%), a biventricular pacemaker can limit the risk of sudden cardiac death. Long‐term anticoagulation in patients with an ejection fraction < 40% should be initiated.
Physicians should be aware of the clinical and radiologic presentation of LVNC. Although it has been thus far a rare entity, the improvement of radiologic techniques suggests that it may be diagnosed more frequently, reducing the number of idiopathic cases of dilated cardiomyopathy.
S. Vora, Massachusetts General Hospital, employment; V. Chiappa, Massachusetts General Hospital, employment.
To cite this abstract:Vora S, Chiappa V. Noncompaction of the Left Ventricle: a Rare Cause of Dilated Cardiomyopathy. Abstract published at Hospital Medicine 2008, April 3-5, San Diego, Calif. Abstract 187. Journal of Hospital Medicine. 2008; 3 (suppl 1). https://www.shmabstracts.com/abstract/noncompaction-of-the-left-ventricle-a-rare-cause-of-dilated-cardiomyopathy/. Accessed April 4, 2020.