THE QTc INTERVAL DURATION СLASS AND CLINICAL FEATURES OF PATIENTS WITH PACEMAKERS IN THE ACUTE POSTOPERATIVE PERIOD

Implantation of the pacemaker (ECS) in the various classes of corrected QTc interval duration of stimulated complexes were investigated. Evaluation was made by sex and age of the patients, chronic forms of ischemic heart disease (CIHD): postinfarction cardiosclerosis, stable angina (I-IV functional classes (FC)); stable angi-na (I-IV FC), arterial hypertension (AH) ? 1-3 degrees and stages (1-4), type of diabetes mellitus (DM), atrial fibrillation (AF) (paroxysmal and persistent, permanent), chronic heart failure (CHF) ? stages I-III, I-IV FC; functional indicators before pacemaker implantation and in the acute postoperative period (3-5 days after surgery): QTc interval duration, heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP); ejection fraction (EF) of the left ventricle (LV), anterior-posterior size of the left atrium (LA), end-systolic volume (ESV) and end-diastolic volume (EDV), the thickness of the back wall of the left ventricle (AP LV), the thickness of the interventricular septum (IVS), left ventricular mass (LVM). The patients were divided into 3 classes: class 1 ? normal QTc (320-440 ms) ? 27 (22 %) patients, class 2 ? elongated QTс (> 440 ms) ? 97 (78 %) patients. Standard statistical procedures using Microsoft Excel were applied for data processing. The results showed that QTc interval duration of stimulated complexes in the acute postoperative period after pacemaker implantation can be established in a physiological range in 22 % of patients, and in 78 % ? it remains longer or even elongated. Elongation associated with a higher incidence and the increase of FC and stages of heart failure, high values of ESV and EDV, mostly in the pacing mode VVI/VVIR and DDD/DDDR. Patients with a pacemaker require more careful monitoring the stimulation parameters as well as ongoing drug therapy.