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

Assiut University

Status: Unknown

Conditions: Wolff-Parkinson-White Syndrome

Treatments: Procedure: electrophysiological study

Study type: Observational

Funder types: Other

Identifiers

NCT04106622

WPW syndrome

Details and patient eligibility

About

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

Full 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....

Enrollment: 35 estimated patients

Sex: All

Volunteers: No Healthy Volunteers

Inclusion and exclusion criteria

1. Inclusion criteria:

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

2. Exclusion criteria:

   1. heart failure
   2. cardiomyopathy

Trial design

35 participants in 1 patient group

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.

Treatment:

Procedure: electrophysiological study