Study On Heart Rate Turbulence In Patients With Dilated Cardiomyopathy

Objective To study the change of heart rate turbulence(HRT) in dilated cardiomyopathy and its relationship with standard deviation of normal-to-normal R-R interals(SDNN),left ventricular ejection fraction(LVEF) and left ventricular end-diastolic diameter(LVEDD).Methods Thirty patients with dilated cardiomyopathy(DCM) and twenty control subjects were investigated . HRT onset and slope were measured by the original definitions using Holter records and analysed its relevance with SDNN,LVEF and LVEDD.Results The value of the HRT onset was significantly higher in DCM group than that in control group(3.18%±6.25 % vs–6.22%±3.68 %,P<0.001 );the value of the HRT slope in DCM group was significantly lower than that in control group (6.06±6.13ms/RR interval vs 13.08±5.54 ms/RR interval,P<0.01 ). There was a significant correlation between TO and SDNN,LVEF,LVEDD in DCM patients. Conclusion Heart rate turbulence is dramatically blunted in DCM patients and maybe become a new predictor of the cardiac autonomic status and risk of sudden cardiac death in DCM patients.