ELECTRICAL, MECHANICAL AND REGULATORY REMODELING IN PATIENTS WITH WPW SYNDROME
Objective: To evaluate the pathophysiological mechanisms of disorders of function of the heart and the effectiveness of radiofrequency ablation (RFA) additional pathways (AP) in patients (pts) with WPW syndrome.
Materials and methods: The study consisted of 36pts (10 women) with WPW syndrome and paroxysmal atrioventricular reciprocating tachycardia (AVRT), 33,4 ± 14,7 years of age, who underwent RFA of additional pathways. Arrhythmia history was 7,1 ± 6,2 years. The frequency of paroxysms orthodromic AVRT was 4,2 ± 4,7 years. Data of electrocardiography, Holter monitoring, echocardiography, heart rate variability (SDNN, rMSSD, TP, LF, HF, LF/HF ratio), quantitative characteristics of chaos (correlation dimension, informational dimensionand fractal dimension) were obtained based on consecutive 4000 R-R intervals recording before RFA and 6 hours, 24 hours, 2 months, 6 months, 12 months after RFA.
Results: Functioning of additional pathways of the heart is accompanied by atrial - ventricular asynchronism, which is reflected in the ECG as a shortened interval PQ, electrical heterogeneity of excitation of its camers - intraventricular and interventricularasynchronism - the broadening of the QRS complex and change of ST-segment and T wave. Asynchrony of reduction impact on contractile function the heart in patients with WPW syndrome. Fraction of ejection in healthy subjects was 70,06 ± 3,43 %, in patients with WPW syndrome 62,88 ± 4,03 %. P = 0,00045. Results received allowed to distinguish the restoration periods after RFA: the early - after 24 hours, late - after 6 months and the period of a complete recovery - after 1 year later after surgery. Any of patients whom operate, wasn’t, showed after RFA.
Conclusions: Electric modernization - the main pathophysiological mechanism of a syndrome of WPW also leads to a disorder of myocardial contractility and disorder of regulatory mechanisms.