Abstract:

Objective To investigate the manifestation and correlation of heart rate deceleration capacity(DC), heart rate deceleration runs(DRs) and heart rate variability(HRV) in patients with myocardial ischemia(MI), in order to provide reference for MI. Methods From october 2019 to August 2020, totally 86 patients with chronic MI were enrolled, of which 59 inpatients with asymptomatic myocardial ischemia(SMI) were regarded as treatment group A, 27 patients with angina pectoris(AP) as treatment group B, 60 healthy adults suspected MI admitted to our hospital were comprised control group, 24h dynamic electrocardiogram(DCG) were monitored, the correlation of DC, Drs and HRV were compared in groups. Results DC, DRs (DR4, DR8) were lower in two treatment groups than in control group (all P<0.05); standard deviation(SD) of all normal to normal(NN) intervals(SDNN), standard deviation of the 5-min average of N-N intervals(SDANN), square root of the mean squared difference of successive RR intervals(RMSSD), percetange of adjacent NN intervals differing by more than 50 milliseconds (pNN50) were lower in two treatment groups than in control group (all P<0.05) ; The above indexes were slightly lower in treatment group A than in treatment group B, but the differences were not statistically significant (all P>0.05). A significant positive correlation were found between DC, DR2, DR4, DR8 and SDNN, SDANN, RMSSD, pNN50 in MI patients (all P<0.05). Conclusion The levels of DC, DRs, HRV in MI patients are lower in comparison with healthy people; and DC, DRs are significantly positively correlated with HRV. DC, DRs, HRV can provide reference for clinical examination of MI.

Key words: myocardial ischemia, heart rate deceleration capacity, dynamic electrocardiogram, heart rate variability