To evaluate the clinical importance of heart rate variability (HEW) in
patients with dilated cardiomyopathy (DCM), time domain and frequency
domain analysis of 24 hour HRV was performed in 40 patients with DCM
(group A): (29(72.5%) patients with ischemic cardiomyopathy andl 1
(27.5%)patients with idiopathic cardio- myopathy,26(65%)males and 14
(35%) females with a mean age 44+12 years/ and 20 normal healthy controls
(group B): 112(6096)males and 8 (4096)fernales with a mean age
43+11 years). All measurements of HRV were significantly reduced in patients
with DCM compared with the control group (P<0.01). 29/40 (72.5%)
patients completed their follow up for 6-2 months; 11 (38%) developed
progressive heart failure (HF7 defined by a deterioration in NYHA finetional
class that was refractory to maximal medical therapy. This group
included 4 cardiac deaths during their follow up. while the remaining 18
(62%) remained clinically stable. Measures of HRV were further reduced
in patients who developed progressive HF during follow up than in those
who remained clinically stable. The SDNNI measure of the time domain
1-IRV was correlated with NYHA functional class, end-diastolic dimension
(EDD) and reduced left ventricular ejection fraction (EF). HRV was reduced
in patients with DCM and related to disease severity. HRV is clinically
useful as an early noninvasive marker of DCM deterioration. |
