Fragmented QRS predicts heart failure progression in patients with hypertrophic cardiomyopathy.
BACKGROUND
Although fragmented QRS complex (frag-QRS) reflecting intra-ventricular conduction delay has been shown to be a prognostic marker for cardiac events, few data exist regarding the impact of frag-QRS on cardiac events in hypertrophic cardiomyopathy (HCM).


RESULTS
Ninety-four HCM patients (56 male; mean age, 58 ± 17 years) were retrospectively investigated. Frag-QRS was defined as the presence of various RsR' patterns in at least 2 contiguous ECG leads. Major arrhythmic events (MAE) were defined as sudden cardiac death, and combined sustained ventricular tachycardia/ventricular fibrillation. New-onset atrial fibrillation (AF) was diagnosed based on ECG during provisional or routine medical examination. Heart failure (HF) with hospitalization was defined as hospital admission due to subjective or objective symptoms. Frag-QRS was detected in 31 patients (33%).TNNI3 was the most frequent disease-causing gene. Median follow-up was 4.6 years. The 4-year cumulative survival rates of cardiac death, MAE, new-onset AF and HF with hospitalization were 97.6%, 94.6%, 87.5% and 89.3%, respectively. On multivariate analysis, frag-QRS was significantly associated with HF with hospitalization (adjusted hazard ratios [95% confidence intervals]: 5.4 [1.2-36], P=0.03). Moreover, HF-free survival was significantly lower in the frag-QRS (+) group compared to the frag-QRS (-) group (79.0% vs. 95.1%, P=0.03).


CONCLUSIONS
Frag-QRS is associated with HF with hospitalization in HCM patients who had a unique distribution of gene mutations.
Division of Cardiovascular Medicine, Kanazawa University Graduate School of Medicine.
Akihiro
A
Nomura
Tetsuo
T
Konno
Takashi
T
Fujita
Yoshihiro
Y
Tanaka
Yoji
Y
Nagata
Toyonobu
T
Tsuda
Akihiko
A
Hodatsu
Kenji
K
Sakata
Hiroyuki
H
Nakamura
Masa-Aki
MA
Kawashiri
Noboru
N
Fujino
Masakazu
M
Yamagishi
Kenshi
K
Hayashi
D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000453:epidemiology / Q000209:etiology; D002312:Cardiomyopathy, Hypertrophic / Q000150:complications / Q000503:physiopathology*; D024741:Cardiomyopathy, Hypertrophic, Familial / Q000150:complications / Q000235:genetics / Q000503:physiopathology; D015897:Comorbidity; D016757:Death, Sudden, Cardiac / Q000453:epidemiology / Q000209:etiology; D018450:Disease Progression; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006329:Heart Conduction System / Q000503:physiopathology*; D006333:Heart Failure / Q000209:etiology* / Q000503:physiopathology; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D006973:Hypertension / Q000150:complications; D007564:Japan / Q000453:epidemiology; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D018570:Risk Assessment; D012518:Sarcomeres / Q000235:genetics; D017180:Tachycardia, Ventricular / Q000453:epidemiology / Q000209:etiology; D014693:Ventricular Fibrillation / Q000453:epidemiology / Q000209:etiology; D014694:Ventricular Outflow Obstruction / Q000209:etiology / Q000503:physiopathology