|Number 16-07: Uhl's Anomaly: You'll recognize it when you see it|
Uhl’s Anomaly: You’ll recognize it when you see it
Fateh Ali Tipoo Sultan1, Babar Hasan1, Vincent L. Sorrell2, Arash Seratnahaei2
1Aga Khan University Hospital, Karachi, Pakistan
2 University of Kentucky Medical Center, Gill Heart Institute, Lexington, KY
A 19 year old male with no previous cardiovascular history presented with NYHA Class III heart failure symptoms. Electrocardiogram on presentation showed normal sinus rhythm with Himalayan P waves (P waves > 5 mm and peaked in lead II), right bundle branch block and right axis deviation.
Figure 1. ECG: Normal sinus rhythm with Himalayan P waves, right bundle branch block, and right axis deviation.
The patient underwent an echocardiogram which reported severe right atrial (RA) and right ventricular (RV) dilation with a pathologically thin RV wall as well as normal tricuspid valve position. The findings were not consistent with Ebstein’s anomaly. Due to his abnormal electrocardiogram and echocardiographic findings, a cardiac MRI (CMR) was obtained for comprehensive RV & left ventricular (LV) quantification, exclusion of cardiac shunt, and myocardial tissue characterization.
A Siemens Avanto 1.5T scanner was employed to obtain imaging sequences which included cine with SSPF, T1 weighted dark blood imaging and late gadolinium enhancement (LGE) imaging.
CMR confirmed the severely dilated RA and RV (RVEDV= 950 mL, indexed RVEDV= 633 mL/m2) with a pathologically thin (essentially unseen) RV myocardial wall. The tricuspid valve was indeed normally positioned and there was severely reduced biventricular systolic function (RVEF 7%, LVEF 20%) (Movies 1, 2, 3 and 4). Tricuspid valve regurgitation (TR) was severe with a regurgitant fraction of 57%. The TR was thought to be secondary to annular dilation and not the primary etiology for the RV pathology. T-1 weighted and LGE images showed no hyperintense signal to suggest fibrofatty infiltration of the RV or LV (Figures 2 and 3). There appeared to be evidence of LGE along the distal free wall and apical RV wall as well as the RV portion of the distal ventricular septum. This finding has not been previously reported and since we do not have any pathologic correlation, our discussion that follows is based upon our review of the relatively scant published literature.
Movie 1: Four-chamber SSFP cine demonstrating a dilated RA, and a RV with a thin wall and normally positioned tricuspid valve. Biventricular systolic dysfunction was present.
Movie 2: RA-RV SSFP cine showing a dilated RA and thin walled RV.
Movie 3: RVOT SSFP cine showing a dilated RV and thin RV wall.
Movie 4: Short axis SSFP cine confirming biventricular systolic dysfunction and showing interventricular septal wall flattening during diastole.
Figure 2: RVOT turbo spin echo T1 weighted (a) and with fat saturation pulse sequence (b) showing no evidence of fibrofatty RV wall infiltration.
Figures 3a and 3b: Short axis LGE images showing enhancement (arrows) along the distal free wall and apical RV wall as well as the RV portion of the distal ventricular septum with a small amount of pericardial effusion. There was no LV wall LGE. Corresponding short axis SSFP cine still (3b) in diastole.
2. Uhl HSM. Uhl’s anomaly revisited. Circulation. 1996;93:1483–1484.
3. James T, Nichols M, Sapire D, et al. Complete heart block and fatal right ventricular failure in an infant. Circulation. 1996;93:1588 –1600.
4. Gerlis L, Schmidt-Ott SC, Ho S, et al. Dysplastic conditions of the right ventricular myocardium: Uhl’s anomaly v arrhythmogenic right ventricular dysplasia. Br Heart J. 1993;69:142–150.
5. Sultan F, George B, Ahmed I, Sorrell V. Cardiac involvement of cystic echinococcosis by cardiac magnetic resonance imaging. http://scmr.site-ym.com/?page=COW1514. Society for Cardiovascular Magnetic Resonance (SCMR) website
Case prepared by Associate Editor: Adrian Dyer