Relationship between heart rate variability and coronary heart disease

Objective To investigate the relationship between Heart Rate Variability( HRV) and Coronary Heart Disease( CHD) by using 24-hour Holter ECG. Methods 35 cases of CHD confirmed by double source coronary artery CT or coronary arteriography were selected as observation group,while 50 subjects without CHD were chosen as control. 24-hour Holter ECG monitoring were performed in all 85 individuals. The HRV indexes including SDNN,RMSSD,pNN50,SDNN index and SDANN were compared between the two groups. Results In the control group,the SDNN was( 128. 32 ± 42. 27) ms,RMSSD was( 49. 29 ± 19. 75) ms,pNN50 was( 14. 86 ± 16. 67) %,SDNN index was( 49. 07 ± 33. 69) ms, SDANN was( 102. 61 ± 35. 02) ms. In the CHD group,SDNN was( 98. 84 ± 25. 76) ms,RMSSD was( 43. 07 ± 21. 81) ms,pNN50 was( 5. 42 ± 5. 62) %,SDNN index was( 31. 42 ± 10. 99) ms,SDANN was( 89. 37 ± 24. 06) ms. SDNN, RMSSD,pNN50,SDNN index and SDANN in the CHD were distinctly reduced as compared to those in the control group. There was significant difference between the two groups( P 0. 01). Conclusion The HRV significantly reduces in the CHD patients which is perhaps associated with the impaired vagus nerve. The HRV analysis using 24 hour dynamic echocardiogram is a noninvasive technology to detect the cardiac autonomic nerve tension and can be used to evaluate the autonomic nerve tension impairment extent in CHD patients.