Septal wall thinning and systolic dysfunction in patients with hypertrophic cardiomyopathy caused by a cardiac troponin I gene mutation.
BACKGROUND
Lysine 183 deletion in the cardiac troponin I gene is 1 of the mutations that causes hypertrophic cardiomyopathy (HCM). However, the clinical course and determinants of poor prognosis in patients with this mutation have not been well established.


RESULTS
We analyzed 10 probands with HCM caused by this mutation and their family members. Forty-six of these 79 subjects were found to be carriers, and 33 were non-carriers. All non-carriers had a percent fractional shortening (%FS) of >25% at all ages. By contrast, 7 of 24 carriers >40 years of age had a %FS of <25%, and no carriers <40 years of age had a %FS of <25%. The change in interventricular septal thickness and the change in %FS were significantly correlated (R = 0.758; P =.0017).


CONCLUSIONS
These results suggest that about 30% of patients with HCM caused by a lysine 183 deletion mutation in the cardiac troponin I gene have systolic dysfunction develop after 40 years of age, and that patients with this mutation whose interventricular septal thickness shows a serial decrease should be followed-up closely for development of systolic dysfunction.
Shimizu
Masami
M
Molecular Genetics of Cardiovascular Disorders, Division of Cardiovascular Medicine, Graduate School of Medical Science, Kanazawa University, Japan. shimizu@med.kanazawa-u.ac.jp
Ino
Hidekazu
H
Okeie
Kazuyasu
K
Yamaguchi
Masato
M
Hayashi
Kenshi
K
Nagata
Mitsuru
M
Itoh
Hideki
H
Iwaki
Taku
T
Oe
Kotaro
K
Konno
Tetsuo
T
Mabuchi
Hiroshi
H
D000328:Adult; D000367:Age Factors; D000368:Aged; D002312:Cardiomyopathy, Hypertrophic / Q000235:genetics* / Q000473:pathology; D005260:Female; D006346:Heart Septum / Q000473:pathology; D006579:Heterozygote; D006801:Humans; D008297:Male; D008875:Middle Aged; D017354:Point Mutation; D011379:Prognosis; D012044:Regression Analysis; D013599:Systole; D019210:Troponin I / Q000235:genetics*
D019210:Troponin I