BIO|Sync-HUTT: Head-up Tilt Test in Patients With Reflex Syncope and Asystolic Response Who Received a Dual-chamber Pacemaker With the Closed Loop Stimulation (CLS) and Participated in the BIOSync Trial

Sponsor

Biotronik SE & Co. KG (Industry)

Overall Status

Completed

CT.gov ID

NCT06038708

Collaborator

(none)

Enrollment

Locations

7.4

Actual Duration (Months)

Patients Per Site

1.4

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

The purpose of this study is to explore changes in patients' hemodynamic parameters during the Head-Up Tilt Test ("HUTT") and their timing with respect to onset of the Closed Loop Stimulation (CLS) pacing. This study aims to add knowledge to better understand the mechanisms underlying recurrent syncopal events and optimal pacing programming.

Condition or Disease	Intervention/Treatment	Phase
Syncope Syncope, Vasovagal

Detailed Description

The 2021 European Society of Cardiology guidelines recommend cardiac pacing in patients aged

40 years with tilt-induced asystolic reflex syncope (class I, level of evidence A). The recommendation relies on recent results from the multicentre, randomised, double-blinded, parallel-design BIOSync trial (NCT02324920). The BIOSync study provided evidence of benefit of dual chamber pacing in patients with tilt-induced reflex syncope and confirmed the role of Head-up Tilt Table (HUTT) test as a diagnostic method for cardiac pacing in reflex syncope. The Closed Loop Stimulation (CLS) is able to measure changes in intracardiac impedance during the systolic phase of each cardiac cycle which are strictly correlated to the increased heart rate and right ventricular contraction speed which are usually present during the pre-syncope phase of the reflex. It was hypothesized that an early onset of CLS pacing may be triggered by the compensatory increase in heart rate to counteract vasodilation and pressure drop during the pre-syncope phase of the reflex. The BIOSync study showed a 77% reduced risk of syncope in the DDD-CLS group as compared to pacing off. The design of the BIOSync study did not allow to assess the specific effect that CLS adds to dual-chamber pacing. Despite DDD-CLS pacing, 22% of patients had syncopal recurrence in 2 years. Further investigations are therefore needed in order to reduce this failure rate. Indeed, it is still unclear whether syncopal recurrences should be ascribed to dominant vasodilation or if the CLS programming/functioning needs optimization to more adequately sustain cardiac output during reflex in these specific cases.

Study Design

Study Type:

Observational [Patient Registry]

Actual Enrollment :

20 participants

Observational Model:

Cohort

Time Perspective:

Prospective

Official Title:

BIO|Sync-HUTT: Head-up Tilt Test in Patients With Reflex Syncope and Asystolic Response Who Received a Dual-chamber Pacemaker With the Closed Loop Stimulation (CLS) and Participated in the BIOSync Trial

Actual Study Start Date :

Sep 29, 2022

Actual Primary Completion Date :

May 12, 2023

Actual Study Completion Date :

May 12, 2023

Outcome Measures

Primary Outcome Measures

Heart rate [bpm] at time of maximum spontaneous heart rate, at time of pacing onset, at time of recovery of spontaneous rhythm after pacing, at time of syncope, at time of time of tilt-down [From the start to the end of the HUTT examination, assessed up to 45 minutes]
Instantaneous measurement of heart rate value at specific time-points during HUTT examination
Systolic and diastolic blood pressure [mmHg] at time of maximum spontaneous heart rate, at time of pacing onset, at time of recovery of spontaneous rhythm after pacing, at time of syncope, at time of time of tilt-down [From the start to the end of the HUTT examination, assessed up to 45 minutes]
Instantaneous measurement of blood pressure at specific time-points during HUTT examination
Stroke volume [ml] at time of maximum spontaneous heart rate, at time of pacing onset, at time of recovery of spontaneous rhythm after pacing, at time of syncope, at time of time of tilt-down [From the start to the end of the HUTT examination, assessed up to 45 minutes]
Instantaneous measurement of stroke volume at specific time-points during HUTT examination
Peripheral resistance [dyn·s/cm5] at time of maximum spontaneous heart rate, at time of pacing onset, at time of recovery of spontaneous rhythm after pacing, at time of syncope, at time of time of tilt-down [From the start to the end of the HUTT examination, assessed up to 45 minutes]
Instantaneous measurement of peripheral resistance at specific time-points during HUTT examination
Time of maximum spontaneous heart rate [s] [From the start to the end of the HUTT examination, assessed up to 45 minutes]
Recording of a specific time-point during HUTT examination
Time of pacing onset [s] [From the start to the end of the HUTT examination, assessed up to 45 minutes]
Recording of a specific time-point during HUTT examination
Time of recovery of spontaneous rhythm after pacing [s] [From the start to the end of the HUTT examination, assessed up to 45 minutes]
Recording of a specific time-point during HUTT examination
Time of syncope [s] [From the start to the end of the HUTT examination, assessed up to 45 minutes]
Recording of a specific time-point during HUTT examination
Time of tilt-down [s] [From the start to the end of the HUTT examination, assessed up to 45 minutes]
Recording of a specific time-point during HUTT examination
Duration of the recovery phase [s] [From the start to the end of the HUTT examination, assessed up to 45 minutes]
Interval from maximum pacing rate to basic rate or spontaneous rhythm
Slope in heart rate [bpm per sec] during the recovery phase [From the start to the end of the HUTT examination, assessed up to 45 minutes]
Calculation of the rate of change of heart rate from the time of maximum pacing rate to the time of basic rate or spontaneous rhythm recovery
Slope in systolic blood pressure (mmHg per sec) during the recovery phase [From the start to the end of the HUTT examination, assessed up to 45 minutes]
Calculation of the rate of change of systolic blood pressure from the time of maximum pacing rate to the time of basic rate or spontaneous rhythm recovery

Eligibility Criteria

Criteria

Ages Eligible for Study:

40 Years and Older

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

Inclusion criteria

Ability to understand the nature of the study.
Willingness to provide written informed consent.
Patients undergoing HUTT for monitoring of syncope, therapy adjustment, training or other medical reasons during ordinary follow-up, irrespective of study participation
Patients who participated in the BIOSync study*.
Patients with a dual-chamber pacing system equipped with the CLS algorithm. * If needed, inclusion of other patients who did not participate in the BIOSync study will be considered to complete study cohort, provided that they have already a CLS pacemaker system and fulfill the same inclusion/exclusion criteria of the BIOSync study.

Exclusion criteria

Pregnant or breast feeding women.
Age less than 40 years.
Patients who after the BIOSync study participation have developed the following:
Any indication to pacemaker different from reflex syncope with positive HUTT response; or
Any classified indication to implantable defibrillator, cardiac resynchronization therapy according to current guidelines; or
Any cardiac dysfunctions likely leading to loss of consciousness (overt heart failure, ejection fraction <40%, myocardial infarction, diagnosis of hypertrophic or dilated cardiomyopathy, clinically significant valvular disease, sinus bradycardia <50 bpm or sinoatrial block, Mobitz I second degree atrioventricular block, Mobitz II second or third degree atrioventricular block, complete bundle-branch block).

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Ospedale di Bolzano - Azienda Sanitaria dell'Alto Adige	Bolzano		Italy	39100
2	Monaldi - AORN dei Colli - Università della Campania "Luigi Vanvitelli"	Napoli		Italy	80131