SYSTOLIC AND DIASTOLIC INTRAVENTRICULAR ASYNCHRONY OF THE LEFT VENTRICULAR MYOCARDIUM IN PATIENTS WITH PACEMAKER

Aim. To study intraventricular asynchrony and effects of pacemaker implantation on asynchrony severity in patients with rhythm and conduction disorders. Material and-methods. The study of 46 patients with cardiac arrhythmia (atrial fibrillation, sick sinus syndrome, AB-block of the third degree) included such examinations as echocardiography, tissue dopplerography (PWTD1) before pacemaker implantation and 7 days after it. Electromechanic systolic and diastolic myocardial asynchrony was assessed by intraventricular heterogeneity index (IHb, IHm, TSD) in 8 segments of the left ventricle (LV) at the basal and mean levels. Values obtained in examination of 32 healthy volunteers were considered normal. Results. Parameters of systolic and diastolic asynchrony in patients with cardiac arrhythmia significantly differ from normal ones. Basal LV diastolic asynchrony was detected in 41-48% patients, systolic one - in 62-100%, systolodiastolic - in 41% cases. Pacemaker implantation into the right heart significantly reduces LV systolic asynchrony while diastolic one was unaffected in an early postoperative period. The best sensitivity in detection of systolic asynchrony is achieved with TsSD index. Informative value of diastolic asynchrony parameters is much less than of the systolic one. Conclusion. Indices of systolic asynchrony (TsSD, IhbS, IhmS) can be used for heart condition control after pacemaker implantation.