Daniel C. Bloomgarden

Congenitally Corrected Transposition of the Great Arteries with Anomalous Inferior Vena Cava Drainage: Multimodality Imaging

Atrioventricular discordance with ventricular‐arterial discordance is a rare cardiac anomaly known as congenitally corrected transposition of the great arteries (CCTGA). This malformation has a prevalence of 0.4–0.6% of all congenital heart disease cases. Complete heart block develops in up to 30% of patients with CCTGA. We present the case of a 62‐year‐old woman diagnosed with CCTGA who, on echocardiography, had anomalous venous drainage where the inferior vena cava (IVC) bypassed the right atrium and drained into the azygos system. Complementary images with magnetic resonance imaging demonstrated the unique anatomical relationship between the IVC, azygos venous system, and the superior vena cava. (Echocardiography 2012;29:E16‐E19)

Myocardial mechanics in noncontiguous HCM.

Marked phenotypic heterogeneity is typical of hypertrophic cardiomyopathy (HCM) with mostly localized and contiguous left ventricular hypertrophy. Rarely, noncontiguous but focal left ventricular hypertrophy is seen [(1)][1]. A more comprehensive assessment of HCM, including segmental distribution

An integrated program for 2-D and 3-D analysis of heart wall motion from magnetic resonance imaging

Magnetic resonance imaging (MRI) with magnetization tagging provides a non invasive tomographic imaging method for the evaluation of cardiac function. We have developed an integrated set of programs for the analysis and display of heart wall motion from cardiac MRI. Cardiac wall contours and tag positions can be extracted manually or semiautomatically from the images. The contours can be stacked to calculate global function variables, or the relative motion of the tags in the images can be used to calculate the regional 2-D strain. Tag data from orthogonal sets of images can be combined to calculate regional 3-D strain. Display options include static or dynamic displays of scalar and vector or tensor quantities. This integrated program provides a useful means to extract and display cardiac function data from tagged MRI.

Registration of orthogonal MR images

Analyses of heart wall motion, cavity volumes and myocardial mass in 3D are essential for understanding global function of the heart. One method for obtaining this information is to acquire two orthogonal series of 2D magnetic resonance (MR) images and reconstruct back to 3D using finite element analysis. Misregistration between the two series can occur due to patient motion. We have developed a program to register orthogonal series. For matching of two series, one series is fixed while the other one can be shifted and rotated with respect to the fired series. The matching process can be done manually or automatically. The manual matching is mouse driven and result is displayed in real time. The automatic method is based on minimizing the mean squared distance between the intersecting points of the contours of the moving series at the imaging plane of the fixed series and the contours of the fixed series. Results of validation tests show good registration for phantom and ex vivo data. The algorithm is also immune to small amount of noise in contours (<15%).

Right ventricular wall mechanics in normals and patients with pulmonary hypertension using magnetic resonance tissue tagging

Right ventricular hypertrophy (RVH) and RV dysfunction are difficult to evaluate due to the complex shape of the RV and prognostic limitations of conventional global function parameters. We used MRI with magnetization tagging to measure 2-D systolic motion and deformation of the right ventricular free wall (RVFW) and septum (SEPT) in 5 patients with RVH secondary to pulmonary hypertension, and 12 normal volunteers (NL). Regional displacement (D) and 2-D principal strains in the short-axis plane were averaged at basal, midventricular and apical levels. SEPT D was severely decreased at all levels in RVH vs. NL (P<0.005). In RVH, RVFW D was higher than SEPT D (P<0.02). The 2-D strains were reduced in SEPT at all levels in RVH vs. NL (P<0.05). This technique may permit the study of progression and regression of RVH in various disease states.