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[Wolf-Parkinson-White syndrome: stratification of syncope risk factors]
Aim:
To evaluate risk factors of syncopes in patients with Wolf-Parkinson-White syndrome (WPWS) using transesophageal pacing (TEP).
Material And Methods:
82 WPWS patients were divided into two groups: the study group (n = 46) with syncopes and presyncopes, the control group (n = 36) without syncopes. The groups were matched by sex and age. TEP protocol included two stages: before radiofrequency ablation (RFA) and on day 2 after RFA (control test).
Results:
Highly significant differences between the groups were detected only in induction of ortodromic tachycardia. In patients of the study group the cycle duration (CD) was 317 +/- 38.9 ms, in the control group - 365.25 +/- 96.3 ms (R = 0.003), heart rate--197.7 +/- 15.03 vs 167.3 +/- 31.65 per 1 min (R = 0.003), heart rate--197.7 +/- 15.03 vs 167.3 +/- 31.65 per 1 min (R = 0.0001), ventricular interval--122.5 +/- 17.5 and 153.1 +/- 44.4 ms (R = 0.0001). A correlation was found between syncope risk and baseline heart rate, CD, Venkebach point, antegrade effective refractory period of additional atrioventricular connection, ventriculoatrial interval during tachycardia, WPWS manifestation, atrial fibrillation, arrhythmia history.
Conclusion:
The detected electrophysiological changes allow early detection of patients at high syncope risk among WPWS patients and reduction of sudden cardiac death risk in these patients.
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