Accessory Pathway Antegrade Effective Refractory Period Among WPW Patients: the Risk in Relation to the Location

Brief Title

Accessory Pathway Antegrade Effective Refractory Period Among WPW Patients: the Risk in Relation to the Location

Official Title

Accessory Pathway Antegrade Effective Refractory Period Among Wolff Parkinson White Patients: the Risk in Relation to the Location

Brief Summary

      To correlate the antegrade effective refractory period of the accessory pathway with its
      anatomical location in the heart.

      To investigate whether the accessory pathway location can predict the high risk nature of the
      accessory pathway

Detailed Description

      The Wolf-Parkinson-White (WPW) syndrome is a clinical entity characterized by the presence of
      ≥1 accessory pathways between the atria and the ventricles pre-disposing patients to
      arrhythmias. Anterograde conduction through the accessory pathway leads to preexcitation of
      the ventricles and a delta wave in the ECG. The prevalence of preexcitation in the general
      population has been estimated to be 1 to 3 in 1000 individuals. Although most asymptomatic
      patients with pre-excitation have a good prognosis, there is also a lifetime risk of
      malignant arrhythmias and SCD, estimated to be 0.1 % per patient year.

        -  More worrisome is the fact that this event can be the first manifestation of the disease
           in up to 53 % of patients.

        -  Atrial fibrillation (AF) can be a life-threatening arrhythmia in the WPW syndrome if the
           AV AP has a short anterograde refractory period (RP), allowing too many atrial impulses
           to be conducted to the ventricle.

        -  This will result in very high ventricular rates with possible deterioration into
           ventricular fibrillation (VF) and sudden death.

        -  Parameters proved to indicate high risk AP include AP effective refractory period <240
           ms, shortest preexcited RR interval <250 ms

        -  Certain Locations were thought to be associated with higher risk of the accessory
           pathway like Septal localization which was significantly more frequent in patients with
           VF when compared with individuals with no VF but the overall number of patients is
           limited . .

      These debatable relations between AP location and its risk stratification was not extensively
      studied in larger scale studies….

Study Type

Observational [Patient Registry]

Primary Outcome

the antegrade refractory period during invasive EPS done for the patients


Wolff-Parkinson-White Syndrome


electrophysiological study

Study Arms / Comparison Groups

 Wolff Parkinson White patients
Description:  The investigators will decide the location of the AP by:
- Invasively: if the patient is subjected to (EPS)
• There are different locations of AP To assess whether the AP is of high risk or not, for all patients the Antegrade refractory period of the APAERP of the AP will be determined by one of the following ways: ( AERP) is measured during EPS as the shortest cycle length with one-to-one conduction over the AP by incremental atrial stimulation after which the QRS becomes narrow or no conduction occurs due to block of the impulse in the AP. The shortest pre-excited R-R interval (SPERRI) during spontaneous or induced AF.
The AERP and the risk category of the AP according to its value, will be recorded in relation to the site of the AP determined in every case and compared between different accessory Locations to see whether some of these positions are more liable to be of higher risk or there is no differerence between different positions.


* Includes publications given by the data provider as well as publications identified by National Clinical Trials Identifier (NCT ID) in Medline.

Recruitment Information

Recruitment Status


Estimated Enrollment


Start Date

March 1, 2020

Completion Date

March 1, 2023

Primary Completion Date

March 1, 2022

Eligibility Criteria

        1. Inclusion criteria:

             all patients with WPW admitted to Assuit university hospital and subjected to invasive

          2. Exclusion criteria:

               1. heart failure

               2. cardiomyopathy




N/A - N/A

Accepts Healthy Volunteers



M K Ibrahim, Msc, 1152453334, [email protected]

Administrative Informations



Organization ID

WPW syndrome

Responsible Party

Principal Investigator

Study Sponsor

Assiut University

Study Sponsor

M K Ibrahim, Msc, Principal Investigator, Assiut University

Verification Date

January 2020