Holter monitoring and long-term prognosis in hypertrophic cardiomyopathy.
OBJECTIVE
Limited data are available regarding Holter monitoring for cardiovascular events except for ventricular tachycardia as a risk marker for sudden death in hypertrophic cardiomyopathy (HCM). We aimed to examine Holter findings in relation to the long-term prognosis in patients with HCM.


METHODS
Ambulatory Holter monitoring was performed in 106 HCM patients with sinus rhythm. All were prospectively followed for the composite endpoint of sudden death, cardiovascular death, and hospitalization for heart failure or stroke associated with atrial fibrillation.


RESULTS
Cardiovascular events occurred in 19 patients during a mean follow-up of 10.1 years. Neither arrhythmia information nor autonomic information as assessed by heart rate variability and turbulence significantly differed between HCM patients with and without cardiovascular events. Average heart rates were lower in HCM patients with cardiovascular events (64.7 ± 11.2 beats/min) than in those without (73.7 ± 10.2 beats/min, p = 0.001). Multivariate Cox proportional hazards regression analysis after adjustment for baseline characteristics showed that lower average heart rate remained an independent predictor of cardiovascular events (HR: 0.47 per 10 increase; 95% CI: 0.25-0.87; p = 0.016).


CONCLUSIONS
Average heart rate on Holter monitoring predicted long-term prognosis in our cohort. Further multicenter studies are needed to confirm our results.
Department of Cardiology, Matsushita Memorial Hospital, Osaka, Japan. js-k@wf6.so-net.ne.jp
Tatsuya
T
Kawasaki
Chieko
C
Sakai
Kuniyasu
K
Harimoto
Michiyo
M
Yamano
Shigeyuki
S
Miki
Tadaaki
T
Kamitani
Hiroki
H
Sugihara
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001145:Arrhythmias, Cardiac / Q000175:diagnosis* / Q000209:etiology; D002312:Cardiomyopathy, Hypertrophic / Q000150:complications*; D016022:Case-Control Studies; D002940:Circadian Rhythm; D016757:Death, Sudden, Cardiac / Q000517:prevention & control; D015716:Electrocardiography, Ambulatory / Q000379:methods*; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008134:Long-Term Care; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D018570:Risk Assessment; D020521:Stroke / Q000517:prevention & control; D055815:Young Adult