LEFT VENTRICULAR NONCOMPACTION CARDIOMYOPATHY: AN UNDERRECOGNIZED CAUSE OF HEART FAILURE

Abstract

SESSION TITLE: Cardiovascular Disease SESSION TYPE: Med Student/Res Case Report PRESENTED ON: 10/09/2018 07:30 AM - 08:30 AM INTRODUCTION: Left ventricular noncompaction cardiomyopathy (LVNC) is a congenital abnormality of myocardial tissue characterized by prominent ventricular trabeculations with deep recesses, which communicate with the LV cavity. It is thought to be caused by the failure of the loose myocardial meshwork to undergo compaction during fetal development (1). Early diagnosis and correct management is crucial due to association with early onset heart failure, development of ventricular arrhythmias, and embolic events (1). CASE PRESENTATION: 53-year-old Caucasian male with history of untreated hypertension presented with chest tightness, dyspnea on exertion, and orthopnea. He had no known cardiac history. Upon presentation, he was hypertensive at 207/132 with heart rate of 97 beats/min and respiratory rate of 18 breaths/min. Troponin was normal at 0.03. BNP was elevated at 648 pg/ml. EKG showed normal sinus rhythm and left atrial enlargement. CXR showed pulmonary vascular congestion and interstitial edema. Hypertensive emergency was treated with nitroglycerin drip. TTE was performed, which showed LVEF of 35 to 40%, LV diastolic dysfunction, moderate asymmetric LVH, mild to moderate increase in LV chamber size and prominent trabeculation at the LV apex (Figs. 1, 2). Due to the echo findings, he underwent coronary angiography, which revealed nonobstructive CAD. He underwent cardiac MRI, which showed diffuse LVH, global LV hypokinesis, and LV noncompaction (Fig. 3). Patient was started on medical therapy for HFrEF, which consisted of aspirin, atorvastatin, carvedilol, furosemide, lisinopril, isosorbide mononitrate, spironolactone. He remained free of heart failure symptoms at 6 week follow up as outpatient. DISCUSSION: Echocardiography is the initial imaging modality used for diagnosis, which shows a 2 layered structure of compacted epicardial and noncompacted endocardial layers; the abnormal noncompacted layer consists of trabeculations with deep endomyocardial recesses (1). Jenni et al criteria are the most commonly used in clinical practice and these are as follows: 1) maximum end-systolic ratio of noncompacted to compacted myocardium >2.0 on short-axis views; 2) absence of other cardiac abnormalities; 3) color doppler showing perfusion of the intratrabecular recesses; 4) predominantly localized to mid-lateral, apical, or mid-inferior regions. CONCLUSIONS: LVNC must be considered within the differential diagnosis of new onset heart failure with nonobstructive findings on coronary angiography. Echocardiogram is the initial imaging modality of choice; however, the major limitation is that the diagnostic criteria have yet to be validated within a larger cohort (1-2). This is especially needed as there are some case reports that suggest conditions leading to high LV preload such as chronic renal failure, valvular heart disease, pregnancy, or sickle cell disease may lead to high prevalence of LV trabeculations (2). Reference #1: Jenni, R. (2001). Echocardiographic and pathoanatomical characteristics of isolated left ventricular non-compaction: a step towards classification as a distinct cardiomyopathy. Heart, 86(6), 666–671. https://doi.org/10.1136/heart.86.6.666 Reference #2: Gati, S., Rajani, R., Carr-White, G. S., & Chambers, J. B. (2014). Adult left ventricular noncompaction: Reappraisal of current diagnostic imaging modalities. JACC: Cardiovascular Imaging, 7(12), 1266–1275. https://doi.org/10.1016/j.jcmg.2014.09.005 Reference #3: Stöllberger, C., Gerecke, B., Engberding, R., Grabner, B., Wandaller, C., Finsterer, J., Balzereit, A. (2015). Interobserver agreement of the echocardiographic diagnosis of LV hypertrabeculation/noncompaction. JACC: Cardiovascular Imaging, 8(11), 1252–1257. https://doi.org/10.1016/j.jcmg.2015.04.026 DISCLOSURES: No relevant relationships by Mirza Ali, source=Web Response No relevant relationships by Abdisamad Ibrahim, source=Web Response