Hypertrophic cardiomyopathy (HCM)

Clinical History:
A 59 year-old man presents with long QT-syndrome and recurrent collapse. Neurologic assessment failed to reveal any abnormalities or pathologic findings. Ultrasound screening of the supraaortic arteries (including specifically the internal carotid and vertebral arteries) was unremarkable.

Diagnosis:
Hypertrophic cardiomyopathy (HCM)

MR Technique:
Cardiac MRI was performed on a 3 T open bore MR System (Magnetom Verio, Siemens Medical Solutions, Erlangen, Germany) with a dedicated 32 element array coil. CINE SSFP images were acquired with a TR/TE of 71/1.3, 930Hz/Px bandwidth, 309×380 mm2 field of view, 156×256 matrix, and 6 mm slice thickness. For reduction of banding artifacts, frequency scouting was implemented. Delayed gadolinium chelate-enhancement images were acquired approximately 15 min after contrast agent application with TR/TE 650/2, TI 340, 285Hz/Px bandwidth, 285×380 mm2 field of view, 144×256 matrix, and 8 mm slice thickness.

 

Imaging Findings:
Cine SSFP imaging shows asymmetric, predominantly septal but partially also anterior and inferior hypertrophy of the left ventricular myocardium (A) with reduced systolic contraction (hypokinesia). The anterior-lateral and inferior-lateral left ventricular walls are unremarkable, specifically with a wall thickness within normal limits.

Delayed post-contrast imaging reveals patchy mid-myocardial enhancement in the thickened and hypertrophic aspects of the myocardium (B). The combination of hypertrophy and late gadolinium enhancement (LGE) is consistent with the diagnosis of hypertrophic cardiomyopathy (HCM). LGE is not present in all patients with HCM but raises the suspicion of increased focal fibrosis and is to be considered as a higher risk of sudden cardiac death in these patients. A further complication of HCM can be an obstruction of the left ventricular outflow tract with increasing pressure gradients.