Delayed hyper-enhancement of myocardium in hypertrophic cardiomyopathy with asymmetrical septal hypertrophy: comparison with global and regional cardiac MR imaging appearances.
OBJECTIVE
To evaluate the relationship between delayed hyper-enhancement of the myocardium and global and regional cardiac abnormalities in hypertrophic cardiomyopathy (HCM) with asymmetrical septal hypertrophy using magnetic resonance (MR) imaging.


METHODS
Twenty-three patients with HCM with asymmetrical septal hypertrophy were examined using a 1.5-T MR unit. Contrast-enhanced inversion-recovery gradient-echo imaging was performed to observe the myocardial damages associated with HCM. Balanced steady-state free precession imaging was performed to assess regional wall abnormalities and ejection fraction, and black-blood fast spin-echo imaging was performed to assess left atrial diameter.


RESULTS
Delayed hyper-enhancement of the myocardium was primarily observed in the interventricular septal wall. Septal walls with the higher transmural extent of delayed hyper-enhancement were significantly thicker at end-diastole and end-systole (P < 0.05), and tended to show a decreased percentage systolic wall thickening (P = 0.079). There were no differences in theses values between non-enhancing septal walls and septal walls with the transmural extent < 50%.


CONCLUSIONS
The high transmural extent of delayed hyper-enhancement of the myocardium may reflect the severe myocardial damage associated with the regional hypertrophy and hypokinesia in HCM.
Amano
Yasuo
Y
Department of Radiology, Nippon Medical School, Tokyo, Japan. yas-amano@nifty.com
Takayama
Morimasa
M
Takahama
Katsuya
K
Kumazaki
Tatuso
T
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D002312:Cardiomyopathy, Hypertrophic / Q000473:pathology*; D003287:Contrast Media / Q000493:pharmacokinetics; D005260:Female; D019786:Gadolinium DTPA / Q000493:pharmacokinetics; D006346:Heart Septum / Q000473:pathology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000473:pathology; D013997:Time Factors
D003287:Contrast Media; D019786:Gadolinium DTPA