Trial Outcomes & Findings for ISSUE3: International Study on Syncope of Uncertain Etiology 3 (NCT NCT00359203)

NCT ID: NCT00359203

Last Updated: 2025-07-18

Results Overview

Intention to treat analysis of percentage of patients with syncope recurrence at 2 years follow-up after study arm assignement

• Recruitment status: COMPLETED
• Study phase: PHASE4
• Target enrollment: 511 participants
• Primary outcome timeframe: 2 years
• Results posted on: 2025-07-18

Participant Flow

From April 2007 to April 2011, 89 out of 511 patients (pts) implanted with implantable loop recorder (ILR) documented an asystolic syncope of >=3 sec or a non-syncopal asystole of >= 6 sec, inclusion criteria to be implanted with a dual chamber pacemaker (PM) and randomized to PM on or PM off. 77 pts out of 89 eligible pts were randomized.

12 out of 89 eligible pts refused randomization

Participant milestones

Measure	Dual Chamber Pacemaker OFF Implant dual chamber pacemaker programmed ODO (switched OFF)	Dual Chamber Pacemeker ON Implant dual chamber pacemaker programmed ON and with Rate Drope Response algorhythm programmed ON
Overall Study STARTED	39	38
Overall Study COMPLETED	39	38
Overall Study NOT COMPLETED	0	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

ISSUE3: International Study on Syncope of Uncertain Etiology 3

Baseline characteristics by cohort

Measure	Dual Chamber Pacemaker OFF n=39 Participants Implant dual chamber pacemaker programmed ODO (switched OFF)	Dual Chamber Pacemeker ON n=38 Participants Implant dual chamber pacemaker programmed ON and with Rate Drope Response algorhythm programmed ON	Total n=77 Participants Total of all reporting groups
Age, Categorical <=18 years	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Age, Categorical Between 18 and 65 years	22 Participants n=5 Participants	17 Participants n=7 Participants	39 Participants n=5 Participants
Age, Categorical >=65 years	17 Participants n=5 Participants	21 Participants n=7 Participants	38 Participants n=5 Participants
Age, Continuous	63 years STANDARD_DEVIATION 12 • n=5 Participants	63 years STANDARD_DEVIATION 14 • n=7 Participants	63 years STANDARD_DEVIATION 13 • n=5 Participants
Sex: Female, Male Female	23 Participants n=5 Participants	18 Participants n=7 Participants	41 Participants n=5 Participants
Sex: Female, Male Male	16 Participants n=5 Participants	20 Participants n=7 Participants	36 Participants n=5 Participants
Region of Enrollment Italy	20 participants n=5 Participants	16 participants n=7 Participants	36 participants n=5 Participants
Region of Enrollment Spain	8 participants n=5 Participants	8 participants n=7 Participants	16 participants n=5 Participants
Region of Enrollment Netherlands	1 participants n=5 Participants	0 participants n=7 Participants	1 participants n=5 Participants
Region of Enrollment Austria	1 participants n=5 Participants	0 participants n=7 Participants	1 participants n=5 Participants
Region of Enrollment Germany	3 participants n=5 Participants	4 participants n=7 Participants	7 participants n=5 Participants
Region of Enrollment Canada	1 participants n=5 Participants	2 participants n=7 Participants	3 participants n=5 Participants
Region of Enrollment France	2 participants n=5 Participants	3 participants n=7 Participants	5 participants n=5 Participants
Region of Enrollment Switzerland	1 participants n=5 Participants	0 participants n=7 Participants	1 participants n=5 Participants
Region of Enrollment United Kingdom	2 participants n=5 Participants	5 participants n=7 Participants	7 participants n=5 Participants

PRIMARY outcome

Timeframe: 2 years

Population: 77 patients implanted with dual chamber pacemaker: 39 patients randomized to pacemaker OFF and 38 patients randomized to pacemaker ON

Intention to treat analysis of percentage of patients with syncope recurrence at 2 years follow-up after study arm assignement

Outcome measures

Measure	Dual Chamber Pacemaker OFF n=39 Participants Implant dual chamber pacemaker programmed ODO (switched OFF)	Dual Chamber Pacemeker ON n=38 Participants Implant dual chamber pacemaker programmed ON and with Rate Drope Response algorhythm programmed ON
Syncope Recurrence Rate	57 percentage of participants Interval 40.0 to 74.0	25 percentage of participants Interval 13.0 to 45.0

Adverse Events

Dual Chamber Pacemaker OFF

Serious events: 3 serious events

Other events: 0 other events

Deaths: 0 deaths

Dual Chamber Pacemeker ON

Serious events: 3 serious events

Other events: 2 other events

Deaths: 0 deaths

Serious adverse events

Measure	Dual Chamber Pacemaker OFF n=39 participants at risk Implant dual chamber pacemaker programmed ODO (switched OFF)	Dual Chamber Pacemeker ON n=38 participants at risk Implant dual chamber pacemaker programmed ON and with Rate Drope Response algorhythm programmed ON
Surgical and medical procedures Right ventricle lead dislodgment	5.1% 2/39 • Number of events 2	0.00% 0/38
Surgical and medical procedures Right atrium lead dislodgment	0.00% 0/39	5.3% 2/38 • Number of events 2
Surgical and medical procedures Subclavian vein thrombosis	2.6% 1/39 • Number of events 1	0.00% 0/38
Neoplasms benign, malignant and unspecified (incl cysts and polyps) Dead	0.00% 0/39	2.6% 1/38 • Number of events 1

Other adverse events

Measure	Dual Chamber Pacemaker OFF n=39 participants at risk Implant dual chamber pacemaker programmed ODO (switched OFF)	Dual Chamber Pacemeker ON n=38 participants at risk Implant dual chamber pacemaker programmed ON and with Rate Drope Response algorhythm programmed ON
Cardiac disorders Atrial arrhythmia	0.00% 0/39	2.6% 1/38 • Number of events 1
Gastrointestinal disorders Gastroenteritis	0.00% 0/39	2.6% 1/38 • Number of events 1

Additional Information

Silvia Giuli

Medtronic Italia SpA

Phone: 003932814224

Email: silvia.giuli@medtronic.com

Results disclosure agreements

• Principal investigator is a sponsor employee
• Publication restrictions are in place