Cardiovascular Journal of Africa: Vol 32 No 6 (NOVEMBER/DECEMBER 2021)

CARDIOVASCULAR JOURNAL OF AFRICA • Volume 32, No 6, November/December 2021 296 AFRICA prevented us from utilising the shortening effect of isoproterenol’s refractory period. Previous studies have shown that isoproterenol will reliably shorten all markers of risk assessment. 21,22 One of the minor limitations is the autonomic effects on heart rate and refractory periods. We tried to abolish the autonomous effect by mild (conscious) sedation during the invasive procedure. One of the least cardiotropic agents, midazolam, was the only agent utilised in the procedures and the mean dose was quite low (1.7 ± 0.2 mg). Finally, the absence of a control group of WPW patients who did not undergo ablation, and lack of follow-up data are also limitations due to the retrospective study design. However, our aim was merely to investigate whether there was a correlation between PDI and established invasive risk factors. Clinical replications are the subject of further research. Conclusions Our results demonstrate that there was a strong correlation between the P- to delta-wave interval and universally accepted risk factors, such as low APERP and AF inducibility. To reach definite conclusions about the predictive value of this surface ECG parameter, long-term follow up of asymptomatic patients who did not undergo ablation is needed. Future studies with larger patient groups would shed more light on our primary work. References 1. Soria R, Guize L, Fernandez F, Chaouat JC, Chretien JM. Prevalence et forms electrocardiographiques du syndrome de Wolff-Parkinson-White. Arch Mal Coeur Vaiss 1982; 75 : 1389–1399. 2. Timmermans C, Smeets JL, Rodriguez LM, Vrouchos G, van den Dool A, Wellens HJ. Aborted sudden death in the Wolff-Parkinson-White syndrome. Am J Cardiol 1995; 76 : 492–494. 3. Pappone C, Santinelli V, Manguso F, AugelloG, Santinelli O, Vicedomini G, et al . 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