Assessing the impact of isosorbide mononitrate on sinoatrial node pacemaker activity in patients with III and IV functional class of stable angina

Aim. To evaluate the peripheral autonomic effects of isosorbide mononitrate on sinoatrial node pacemaker activity using wave structure analysis by rhythmocardiography. Methods. The study included 162 patients with III and IV functional classes of stable angina, among them 122 - with hypertension. The control group consisted of 42 healthy volunteers. In addition to standard techniques (electrocardiography, echocardiography, bicycle ergometry, electrocardiogram daily monitoring), high-resolution rhythmocardiography using a KAP-RK-01-«Mikor» diagnostic complex with time and spectral analysis of the sinus rhythm wave structure was performed. The method is based on the evaluation of peripheral autonomic regulation in the sinoatrial pacemaker and influence of humoral and metabolic environment on it. Results. In all patients with III and IV functional classes of stable angina regardless of the concomitant arterial hypertension heart rate variability, as well as Valsalva maneuver response increased in a number of patients taking isosorbide mononitrate. Negative events related to isosorbide mononitrate intake were reduced parasympathetic fluctuations in a number of cases, humoral-metabolic regulation growth, and increase of sympathetic regulation role in patients with concomitant arterial hypertension. Rhythmocardiography allowed to access the influence of isosorbide mononitrate on heart rate variability in patients with ischemic heart disease. Conclusion. Both positive (increased heart rate variability) and negative (spectral features redistribution with humoral, metabolic and sympathetic components increase and parasympathetic component decrease) effects were associated with isosorbide mononitrate intake with lesser sinoatrial node dysregulation in patients with concomitant arterial hypertension.

rhythmocardiography, heart rate variability, stable angina, arterial hypertension, isosorbide mononitrate