Clinical features of the dilated phase of hypertrophic cardiomyopathy in comparison with those of dilated cardiomyopathy.
BACKGROUND
Although the dilated phase of hypertrophic cardiomyopathy (D-HCM) characterized by left ventricular (LV) systolic dysfunction and cavity dilatation has been reported to be a poor prognosis, this is now in contrast to the improved prognosis of dilated cardiomyopathy (DCM) in the era of advancements in heart failure management. There has been no investigation of the clinical features of D-HCM compared with those of DCM from the point of management of systolic dysfunction.


OBJECTIVE
The aim of this study was to investigate the clinical features of D-HCM in comparison with those of DCM in a single institute.


METHODS
We studied 20 consecutive patients with D-HCM (global ejection fraction < 50%) and 115 consecutive patients with DCM.


RESULTS
At diagnosis of D-HCM, 8 (40%) of the D-HCM patients already experienced dyspnea (New York Heart Association [NYHA] class >or= III). Left atrial diameter was larger and prevalence of atrial fibrillation was higher in the D-HCM group, although LV size was larger and LV ejection fraction was lower in the DCM group. During the follow-up period (4.0 years), 11 (55%) of the patients with D-HCM died. The 5-year survival rate from all-cause mortality including cardiac transplantation was 45.6% in patients with D-HCM vs 81.6% in patients with DCM (log-rank P = .0001).


CONCLUSIONS
Patients with D-HCM were more symptomatic at diagnosis, although LV dilatation and impaired fractional shortening seemed more severe in patients with DCM. The prognosis for D-HCM patients was worse than that for patients with DCM despite similar or even more intensive treatment for heart failure.
Hamada
Tomoyuki
T
Department of Medicine and Geriatrics, Kochi Medical School, Nankoku-shi, Kochi, Japan.
Kubo
Toru
T
Kitaoka
Hiroaki
H
Hirota
Takayoshi
T
Hoshikawa
Eri
E
Hayato
Kayo
K
Shimizu
Yuji
Y
Okawa
Makoto
M
Yamasaki
Naohito
N
Matsumura
Yoshihisa
Y
Yabe
Toshikazu
T
Takata
Jun
J
Doi
Yoshinori L
YL
D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000209:etiology; D002311:Cardiomyopathy, Dilated / Q000150:complications* / Q000401:mortality / Q000503:physiopathology / Q000628:therapy; D002312:Cardiomyopathy, Hypertrophic / Q000150:complications* / Q000401:mortality / Q000503:physiopathology / Q000628:therapy; D016009:Chi-Square Distribution; D018450:Disease Progression; D004417:Dyspnea / Q000209:etiology; D005260:Female; D006333:Heart Failure / Q000209:etiology* / Q000401:mortality / Q000503:physiopathology / Q000628:therapy; D016027:Heart Transplantation; D006801:Humans; D007564:Japan; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D018570:Risk Assessment; D012307:Risk Factors; D013318:Stroke Volume; D015996:Survival Rate; D013997:Time Factors; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000209:etiology* / Q000401:mortality / Q000503:physiopathology / Q000628:therapy; D016277:Ventricular Function, Left; D020257:Ventricular Remodeling