Prevalence, clinical profile, and significance of left ventricular remodeling in the end-stage phase of hypertrophic cardiomyopathy.
BACKGROUND
End stage (ES) is a recognized part of the hypertrophic cardiomyopathy (HCM) disease spectrum. Frequency, clinical profile and course, and treatment strategies in these patients remain incompletely defined.


RESULTS
Three HCM cohorts comprised 1259 patients, including 44 (3.5%) characterized as ES with systolic dysfunction (ejection fraction <50% at rest; range 15% to 49%). ES developed at a wide age range (14 to 74 years), with 45% of patients < or = 40 years old. Although 29 patients (66%) died of progressive heart failure, had sudden death events, or underwent heart transplantation, 15 (34%) survived with medical management over 3+/-3 years. Duration from onset of HCM symptoms to ES identification was considerable (14+/-10 years), but ES onset to death/transplantation was brief (2.7+/-2 years). ES occurred with similar frequency in patients with or without prior myectomy (P=0.84). Appropriate defibrillator interventions were 10% per year in patients awaiting donor hearts. Most ES patients (n=23; 52%) showed substantial left ventricular (LV) remodeling with cavity dilatation. Less complete remodeling occurred in 21 patients (48%), including 5 with persistence of a nondilated and markedly hypertrophied LV. Pathology and magnetic resonance imaging showed extensive (transmural) fibrosis in 9 of 11 ES patients. At initial evaluation, patients who developed ES were younger with more severe symptoms, had a larger LV cavity, and more frequently had a family history of ES than other HCM patients.


CONCLUSIONS
ES of nonobstructive HCM has an expanded and more diverse clinical expression than previously appreciated, including occurrence in young patients, heterogeneous patterns of remodeling, frequent association with atrial fibrillation, and impaired LV contractility that precedes cavity dilatation, wall thinning, and heart failure symptoms. ES is an unfavorable complication (mortality rate 11% per year) and a sudden death risk factor; it requires vigilance to permit timely recognition and the necessity for defibrillator implantation and heart transplantation.
Harris
Kevin M
KM
Hypertrophic Cardiomyopathy Center, Minneapolis Heart Institute Foundation, 920 E 28th St, Suite 60, Minneapolis, Minnesota 55407, USA.
Spirito
Paolo
P
Maron
Martin S
MS
Zenovich
Andrey G
AG
Formisano
Francesco
F
Lesser
John R
JR
Mackey-Bojack
Shannon
S
Manning
Warren J
WJ
Udelson
James E
JE
Maron
Barry J
BJ
D000293:Adolescent; D000328:Adult; D002312:Cardiomyopathy, Hypertrophic / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000473:pathology / Q000503:physiopathology*; D002648:Child; D015331:Cohort Studies; D004452:Echocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D015995:Prevalence; D012189:Retrospective Studies; D013997:Time Factors; D014481:United States / Q000453:epidemiology; D020257:Ventricular Remodeling / Q000502:physiology*