Cardiac Imaging in Isolated Noncompaction of Ventricular Myocardium
A 42-year-old man with previously diagnosed dilated cardiomyopathy due to alcohol abuse was referred to our clinic for further diagnostic procedures. Cardiac catheterization (cine loop 1: Figure 1 and Movie I) demonstrated left ventricular dilatation with obviously hypokinetic basal and apical segments, a restrictive filling pattern (“square root sign”), moderate mitralic regurgitation, and no obstruction of the left ventricular outflow tract. Impaired systolic function was confirmed by an ejection fraction of 28%. After injection of a contrast medium, the basal and apical segments showed remarkable opacification, as evidenced by a loosened, spongy myocardium without indication of ventricular blood communication with the epicardial coronary artery system. Along with previously performed echocardiographic imaging, hereditary isolated noncompaction of ventricular myocardium (INVM) was diagnosed.
Additional screening of the relatives also revealed INVM in an asymptomatic half-sister (age, 40 years). Her echocardiographic imaging showed a regular-sized left chamber (left ventricular end-diastolic diameter, 54 mm) with hypertrophied apical segments. The myocardium appeared loosened, with deep intramyocardial recesses and prominent trabeculations comparable to those seen in her brother’s echocardiography images. Color Doppler imaging of the apical myocardium (cine loop 2: Figure 2 and Movie II) demonstrated blood flow throughout the trabeculations. Fractional shorten-ing was calculated as 22%. Additionally, her cardiac MRI (cine loop 3: Figure 3 and Movie III) showed a typical myocardial appearance of both ventricles in this rare congenital disorder.
In conclusion, diagnosis of INVM is made mainly on the basis of sufficient cardiac imaging, including echocardiographic imaging, catheterization, and MRI or CT.
Movies I, II, and III are available in an online-only Data Supplement at http://www.circulationaha.org.
The editor of Images in Cardiovascular Medicine is Hugh A. McAllister, Jr, MD, Chief, Department of Pathology, St Luke’s Episcopal Hospital and Texas Heart Institute, and Clinical Professor of Pathology, University of Texas Medical School and Baylor College of Medicine.
Circulation encourages readers to submit cardiovascular images to the Circulation Editorial Office, St Luke’s Episcopal Hospital/Texas Heart Institute, 6720 Bertner Ave, MC1-267, Houston, TX 77030.