Noncompaction of the Ventricular Myocardium

Abstract

ase Presentation: A 42-yearold woman was referred to the Hypertrophic Cardiomyopathy Clinic. A diagnosis of apical hypertrophic cardiomyopathy had been given 16 years earlier on the basis of echocardiographic findings. Left ventricular systolic function was reportedly at the lower limit of normal 5 years earlier.The patient gave a 6-month history of mild dyspnea occurring during exertion. Although still active, her exercise tolerance had decreased. She also complained of more frequent and sustained episodes of rapid palpitations associated with shortness of breath. She had occasional episodes of heavy, burning discomfort in the chest during activity and while at rest.There was no family history of cardiomyopathy, although first degree relatives had not been screened. Her heart rate was 74. Blood pressure was 110/ 70. Jugular venous pressure was normal. Carotid pulse volume and contour were normal. The first and second heart sounds were normal. There was a presystolic apical impulse and a prominent S4 gallop. There was no S3 gallop. A grade III/VI, harsh, midsystolic murmur was heard best at the upper left sternal border. There was no diastolic murmur.The ECG showed sinus rhythm, normal QRS duration, and left ventricular hypertrophy with repolarization changes. An echocardiogram demonstrated marked thickening and heavy trabeculation of the apical half of the left ventricle. Color Doppler displayed flow within the deep intertrabecular recesses. The left ventricle was not dilated. There was diffuse left ventricular hypokinesis with an ejection fraction of 20% to 25%. The right ventricle appeared to be more heavily trabeculated than usual. No additional abnormalities were present. The findings were consistent with isolated noncompaction of the ventricular myocardium.

Dependence of cardiac trabeculation on neuregulin signaling and blood flow in zebrafish

“…Both aspects of ventricular topography contribute to this chamber's characteristic contractile strength and compliant filling, and these properties determine a ventricle's overall workload efficacy (Icardo and Fernandez-Teran, 1987;Sanchez-Quintana and Hurle, 1987;Sedmera et al, 2000;Hu et al, 2001). Of clinical importance, infants born with a hypotrabeculated ventricle exhibit compromised hemodynamics; conversely, infants born with a hypertrabeculated ventricle can demonstrate impaired diastolic function, secondary to lack of compliance and ultimately leading to inadequate filling of the ventricle (Weiford et al, 2004;Breckenridge et al, 2007). Despite the clinical relevance of deficient or increased trabeculation, the cellular mechanisms governing trabeculation and their genetic regulation are relatively understudied.…”

Isolated left ventricular noncompaction in a patient presenting with a subacute myocardial infarction

“…The most common causes of death are heart failure and sudden cardiac death. 12 High-risk features for death include higher left ventricular end-diastolic diameter on presentation, New York Heart Association class III-IV, permanent or persistent atrial fibrillation, and bundle branch block. 13 Because of the supposed familial association of isolated noncompaction, screening of first-degree relatives by echocardiography is recommended.…”

Cardiomyopathy mimicking left ventricular noncompaction in a patient with lupus nephritis

“…LVNC, also called left ventricular hypertrabeculation, is a rare morphologically distinct primary genetic cardiomyopathy [1]. It is due to the failure of condensation of the myocardial spongy meshwork of fibers and intertrabecular recesses during intrauterine life leading to the persistence of ventricular trabeculations [2].…”

“…It is thought to be due to the failure of condensation of the myocardial meshwork of fibers during intrauterine life, leading to persistence of ventricular trabeculations [1,2]. The major clinical manifestations of LVNC are heart failure, systemic thromboembolism, ventricular arrhythmias, conduction disorders, and neurologic abnormalities.…”