Isolated Noncompaction of Ventricular Myocardium: a Magnetic Resonance Imaging Study of 11 Patients

Abstract

ObjectiveTo retrospectively summarize the cardiac magnetic resonance imaging (CMRI) findings of isolated noncompaction of ventricular myocardium (INVM).Materials and MethodsEleven patients (M:F = 9:2; mean age, 35 years) were evaluated. Steady-state free precession (SSFP), fast spin echo (SE) sequence, SSFP cine imaging, and delayed enhanced inversion recovery spoiled gradient echo (IR-SPGR) sequence were used for showing abnormal myocardium, measuring ratio of noncompacted/compacted myocardium layers (NC/C ratio), and detecting myocardial viability. The left ventricle was divided into nine segments and a NC/C ratio > 2.3 in diastole was used as cutoff value in diagnosing left INVM. The right ventricle was assessed qualitatively.ResultsCardiac MRI indicated left INVM in seven patients, right INVM in one patient and biventricle INVM in three patients. Characteristic CMRI changes included prominent trabeculations, deep intertrabecular recesses and an increase in the NC/C ratio. The most frequently involved segments was left ventricular apex. Three patients had abnormal high signals within the trabecular structures on SE T2 weighted image. One ventricular aneurysm and one apical thrombus were also observed. Delayed enhancement was seen in six of nine patients with subendocardial and transmural patterns.ConclusionThere are CMRI features that might be characteristic for INVM.

Isolated Left Ventricular Noncompaction with a Congenital Aneurysm Presenting with Recurrent Embolism

“…There have been many reports of coexistent congenital cardiac disorders, including atrial septal defect, ventricular septal defect, pulmonary stenosis, anomalous pulmonary venous connection, Ebstein's anomaly, and a bicuspid aortic valve 3-6). However, only a few cases of LVNC with LV aneurysm have been reported 10-12). The mechanism of aneurysm is uncertain.…”

Left Ventricular Noncompaction

“…9 Magnetic resonance imaging (MRI) is superior to all other modalities in differentiating blood and thrombus from myocardial tissue in noncompacted myocardium. 23 In the systematic overview conducted by Bhatia et al, 3 8% of LVNC subjects experienced thromboembolic events. It is important to recognize that no association was found between the presence of left ventricle thrombus and thromboembolic events.…”

“…9,23,29 Advantages of cMRI go beyond the superior imaging and reconstruction capabilities to include less operator dependence and variations in image quality related to patient chest wall thickness and habitus that exists with TTE. 23 Cardiac MRI allows for more detailed morphological evaluation of the LV in any plane and yields the highest sensitivity (86%) and specificity (99%) of any modality. 9 Cardiac MRI also has the highest positive and negative predictive values of 75% and 99%, respectively, of all modalities.…”

“…29 Cardiac CT has some advantage in its ability to visualize epicardial coronary circulation and exclude the presence of anomalies or stenosis but falls short of cMRI's ability to evaluate myocardial viability and presence of fibrosis through the use of delayed enhancement imaging. 1,23 Conclusions Left ventricular noncompaction, whether found alone or as part of a clinical syndrome, is an important clinical entity that requires prompt diagnosis and treatment. Accurate diagnosis is necessary so that management can be directed toward the prevention of the morbidity and mortality associated with heart failure, SCD, and systemic thromboembolic arterial events from ventricular thrombus formation.…”

“…Cardiac MRI is superior for demonstrating the contrast between intertrabecular blood pools and myocardial tissue (Figure 3). 23 In case where cMRI is contraindicated, cCT is available, and the ability to use low-radiation dose protocols allows for less exposure to the patient. Typical diagnostic criteria for ILVNC by cMRI are the presence of prominent and numerous trabeculations, multiple deep trabecular recesses in communication with the ventricular cavity, and a 2-layered myocardium.…”