Trial Outcomes & Findings for DATAS: The Dual Chamber & Atrial Tachyarrhythmias Adverse Events Study (NCT NCT00157820)

NCT ID: NCT00157820

Last Updated: 2025-07-02

Results Overview

Main outcome was defined as the CSAE-score during follow-up: CSAE-score rate. We assigned death as the worst outcome during the entire study; and premature cross-over as the main failure of the assigned therapy. So each CSAE was assigned 1 point but (a) death was assigned a score equal to the max number of CSAE in any individual patient in the entire study +1, and (b) premature authorized crossover was given a score equal to the max number of CSAE in any individual patient in that period. Thus, main outcome was defined as the CSAE-score over length of follow-up resulting in a CSAE-score rate.

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

354 participants

Primary outcome timeframe

17 months

Results posted on

2025-07-02

Participant Flow

Patients were eligible if they met a standard Class I indication for a Single Chamber-Implantable Cardioverter Defibrillator (ICD) according to the 1998 ACC/AHA guidelines. Every patient eligible for ICD was screened at each study centre. Follow-up started immediately after randomization.

The Dual chamber true (DC true) and Single chamber simulated (SC sim) arms crossed over after 8 months. All other crossovers were considered 'premature crossovers' and had to be authorized by an independent Adverse Events Advisory Committee. A 1-month wash out period was implemented after programmed crossover.

Participant milestones

Participant milestones
Measure
SC True
Allocated to Single Chamber ICD (SC true arm) VVEV-VVI (NASPE/BPEG Defibrillator/Pacemaker Codes)
SC Simulated Then DC True
Dual chamber ICD initially programmed as Single Chamber ICD (simulated) then DC true programmed as Dual Chamber true (DDED-DDDR) NASPE/BPEG Defibrillator/Pacemaker Codes.
DC True Then SC Sim
Dual chamber ICD initially programmed as a DDED-DDDR ("DC true arm") then programmed as Single Chamber simulated
Randomized
STARTED
118
116
120
Randomized
COMPLETED
111
111
112
Randomized
NOT COMPLETED
7
5
8
1st 8 Month
STARTED
111
111
112
1st 8 Month
COMPLETED
103
99
106
1st 8 Month
NOT COMPLETED
8
12
6
1 Month Wash Out Period
STARTED
103
101
108
1 Month Wash Out Period
COMPLETED
103
101
108
1 Month Wash Out Period
NOT COMPLETED
0
0
0
2nd 8 Months
STARTED
103
101
108
2nd 8 Months
COMPLETED
98
88
94
2nd 8 Months
NOT COMPLETED
5
13
14

Reasons for withdrawal

Reasons for withdrawal
Measure
SC True
Allocated to Single Chamber ICD (SC true arm) VVEV-VVI (NASPE/BPEG Defibrillator/Pacemaker Codes)
SC Simulated Then DC True
Dual chamber ICD initially programmed as Single Chamber ICD (simulated) then DC true programmed as Dual Chamber true (DDED-DDDR) NASPE/BPEG Defibrillator/Pacemaker Codes.
DC True Then SC Sim
Dual chamber ICD initially programmed as a DDED-DDDR ("DC true arm") then programmed as Single Chamber simulated
Randomized
Physician Decision
4
2
3
Randomized
Withdrawal by Subject
1
2
3
Randomized
Protocol Violation
2
1
2
1st 8 Month
Death
7
8
3
1st 8 Month
Lost to Follow-up
1
2
1
1st 8 Month
Premature cross-over
0
2
2
2nd 8 Months
Death
3
1
3
2nd 8 Months
Lost to Follow-up
1
5
2
2nd 8 Months
Premature cross-over
1
7
9

Baseline Characteristics

DATAS: The Dual Chamber & Atrial Tachyarrhythmias Adverse Events Study

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
SC True
n=111 Participants
Allocated to Single Chamber ICD (SC true arm) VVEV-VVI (NASPE/BPEG Defibrillator/Pacemaker Codes)
SC Simulated Then DC True
n=111 Participants
Dual chamber ICD initially programmed as Single Chamber ICD (simulated) then DC true programmed as Dual Chamber true (DDED-DDDR) NASPE/BPEG Defibrillator/Pacemaker Codes.
DC True Then SC Sim
n=112 Participants
Dual chamber ICD initially programmed as a DDED-DDDR ("DC true arm") then programmed as Single Chamber simulated
Total
n=334 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
0 Participants
n=4 Participants
Age, Categorical
Between 18 and 65 years
63 Participants
n=5 Participants
61 Participants
n=7 Participants
53 Participants
n=5 Participants
177 Participants
n=4 Participants
Age, Categorical
>=65 years
48 Participants
n=5 Participants
50 Participants
n=7 Participants
59 Participants
n=5 Participants
157 Participants
n=4 Participants
Age, Continuous
63 years
STANDARD_DEVIATION 10 • n=5 Participants
62 years
STANDARD_DEVIATION 11 • n=7 Participants
66 years
STANDARD_DEVIATION 9 • n=5 Participants
64 years
STANDARD_DEVIATION 10 • n=4 Participants
Sex: Female, Male
Female
11 Participants
n=5 Participants
21 Participants
n=7 Participants
20 Participants
n=5 Participants
52 Participants
n=4 Participants
Sex: Female, Male
Male
100 Participants
n=5 Participants
90 Participants
n=7 Participants
92 Participants
n=5 Participants
282 Participants
n=4 Participants
Region of Enrollment
Spain
43 participants
n=5 Participants
44 participants
n=7 Participants
44 participants
n=5 Participants
131 participants
n=4 Participants
Region of Enrollment
Germany
29 participants
n=5 Participants
29 participants
n=7 Participants
31 participants
n=5 Participants
89 participants
n=4 Participants
Region of Enrollment
Italy
21 participants
n=5 Participants
21 participants
n=7 Participants
19 participants
n=5 Participants
61 participants
n=4 Participants
Region of Enrollment
Israel
9 participants
n=5 Participants
8 participants
n=7 Participants
9 participants
n=5 Participants
26 participants
n=4 Participants
Region of Enrollment
United Kingdom
6 participants
n=5 Participants
6 participants
n=7 Participants
6 participants
n=5 Participants
18 participants
n=4 Participants
Region of Enrollment
Portugal
3 participants
n=5 Participants
3 participants
n=7 Participants
3 participants
n=5 Participants
9 participants
n=4 Participants
LVEF
35 percentage
STANDARD_DEVIATION 13 • n=5 Participants
39 percentage
STANDARD_DEVIATION 14 • n=7 Participants
34 percentage
STANDARD_DEVIATION 12 • n=5 Participants
36 percentage
STANDARD_DEVIATION 13 • n=4 Participants

PRIMARY outcome

Timeframe: 17 months

Population: ITT

Main outcome was defined as the CSAE-score during follow-up: CSAE-score rate. We assigned death as the worst outcome during the entire study; and premature cross-over as the main failure of the assigned therapy. So each CSAE was assigned 1 point but (a) death was assigned a score equal to the max number of CSAE in any individual patient in the entire study +1, and (b) premature authorized crossover was given a score equal to the max number of CSAE in any individual patient in that period. Thus, main outcome was defined as the CSAE-score over length of follow-up resulting in a CSAE-score rate.

Outcome measures

Outcome measures
Measure
SC True
n=82 CSAE
Allocated to Single Chamber ICD (SC true arm)
SC Simulated
n=84 CSAE
Dual chamber ICD initially programmed as Single Chamber ICD (simulated)
DC True
n=65 CSAE
Dual chamber ICD initially programmed as a DDED-DDDR ("DC true arm"
CSAE-score Rate(Clinical Significant Adverse Events Score Rate)
0.112 score/month
0.128 score/month
0.075 score/month

SECONDARY outcome

Timeframe: 17 months

The primary endpoint is a composite of 5 pre-determine Clinical Significant Adverse Events (CSAE): (1) all-cause mortality, (2) invasive intervention due to Cardiovascular cause, (3) hospitalization (\>24h) or prolongation of hospitalization due to CV, (4) inappropriate shocks: two or more episodes with inappropriate shocks, (5) sustained symptomatic ATs that (a) require urgent termination or (b) lasted more than 48 h leading to therapeutic intervention. Number of each of the components of CSAE, counts the number of events for each pre-determined level.

Outcome measures

Outcome measures
Measure
SC True
n=111 Participants
Allocated to Single Chamber ICD (SC true arm)
SC Simulated
n=223 Participants
Dual chamber ICD initially programmed as Single Chamber ICD (simulated)
DC True
n=223 Participants
Dual chamber ICD initially programmed as a DDED-DDDR ("DC true arm"
Number of Each of the Components of the CSAE
Death
10 events
11 events
4 events
Number of Each of the Components of the CSAE
Invasive intervention CV
11 events
12 events
10 events
Number of Each of the Components of the CSAE
Hospitalizations (>24h) or prolongued CV
42 events
51 events
47 events
Number of Each of the Components of the CSAE
Inappropiate shocks (>2 episodes)
13 events
7 events
3 events
Number of Each of the Components of the CSAE
Long Duration AT
6 events
3 events
1 events

Adverse Events

SC True

Serious events: 50 serious events
Other events: 13 other events
Deaths: 0 deaths

SC Simulated

Serious events: 49 serious events
Other events: 8 other events
Deaths: 0 deaths

DC True

Serious events: 44 serious events
Other events: 3 other events
Deaths: 0 deaths

Serious adverse events

Serious adverse events
Measure
SC True
n=111 participants at risk
Allocated to Single Chamber ICD (SC true arm)
SC Simulated
n=223 participants at risk
Dual chamber ICD initially programmed as Single Chamber ICD (simulated
DC True
n=223 participants at risk
Dual chamber ICD initially programmed as a DDED-DDDR ("DC true arm")
General disorders
Death
9.0%
10/111 • Number of events 10 • Duration of the enrollment+follow up
4.9%
11/223 • Number of events 11 • Duration of the enrollment+follow up
1.8%
4/223 • Number of events 4 • Duration of the enrollment+follow up
Cardiac disorders
Invasive interventions
9.9%
11/111 • Number of events 11 • Duration of the enrollment+follow up
5.4%
12/223 • Number of events 12 • Duration of the enrollment+follow up
4.0%
9/223 • Number of events 10 • Duration of the enrollment+follow up
Cardiac disorders
Hospitalization or prolongued hospitalizations
29.7%
33/111 • Number of events 42 • Duration of the enrollment+follow up
14.3%
32/223 • Number of events 51 • Duration of the enrollment+follow up
16.1%
36/223 • Number of events 47 • Duration of the enrollment+follow up

Other adverse events

Other adverse events
Measure
SC True
n=111 participants at risk
Allocated to Single Chamber ICD (SC true arm)
SC Simulated
n=223 participants at risk
Dual chamber ICD initially programmed as Single Chamber ICD (simulated
DC True
n=223 participants at risk
Dual chamber ICD initially programmed as a DDED-DDDR ("DC true arm")
Cardiac disorders
Innapropiate shocks
9.0%
10/111 • Number of events 23 • Duration of the enrollment+follow up
3.1%
7/223 • Number of events 14 • Duration of the enrollment+follow up
0.90%
2/223 • Number of events 5 • Duration of the enrollment+follow up
Cardiac disorders
Sustain Symptomatic AT
4.5%
5/111 • Number of events 6 • Duration of the enrollment+follow up
1.8%
4/223 • Number of events 4 • Duration of the enrollment+follow up
0.45%
1/223 • Number of events 1 • Duration of the enrollment+follow up

Additional Information

Dr.A.Quesada

Hospital General Universitario de Valencia, Spain

Results disclosure agreements

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

Restriction type: LTE60