The primary objective of the study is to determine whether the optimal atrioventricular delay and interventricular delay in cardiac resynchronization therapy are a function of exercise. Secondary objectives are the development of an automatic…
ID
Source
Brief title
Condition
- Heart failures
Synonym
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
The difference, in milliseconds, between the optimal AVD/VVD during resting
conditions versus exercise.
Secondary outcome
To reach the secondary objectives, the following parameters are also measured:
the intrinsic atrio- and interventricular conduction times on the intracardiac
electrogram; coronary sinus dP/dt; a matrix with the dP/dt for all possible
combinations of AVD*s and VVD*s. Moreover echocardiographic indices of
mechanical asynchrony during rest and dobutamine infusion are determined.
Background summary
The aim of cardiac resynchronization therapy (CRT) is to correct ventricular
dyssynchrony with a biventricular pacemaker and thereby diminish systolic
dysfunction in patients with chronic heart failure. Individualized optimization
of the atrioventricular delay (AVD) and interventricular delay (VVD) by
echocardiography or invasive pressure measurements (dP/dt) is a cardinal
component for the benefits. The optimal AVD/VVD during resting conditions is
programmed in the CRT device. This fixed AVD/VVD could diminish the positive
effect of CRT on the systolic function during exercise or even be
counterproductive. In healthy subjects, the AVD shortens with exercise, and in
three small monocenter studies the optimal AVD either lengthened or shortened.
Nothing is published about the optimal VVD during exercise. This study will
determine the difference between the optimal AVD/VVD during rest and exercise
and a shortening of both AVD and VVD is expected during exercise.
Study objective
The primary objective of the study is to determine whether the optimal
atrioventricular delay and interventricular delay in cardiac resynchronization
therapy are a function of exercise. Secondary objectives are the development of
an automatic algorithm for VVD optimization; to determine whether the optimal
AVD is a function of the VVD and vice versa; to compare the left ventricular
rate of pressure rise (dP/dt) to the dP/dt in the coronary sinus; to determine
whether the optimal AVD/VVD are correlated to the intrinsic atrio- and
interventricular conduction times; to determine whether the changes in optimal
AVD/VVD during rest and exercise are related to the changes in mechanical
dyssynchrony during rest and exercise.
Study design
This is a prospective single center observational study with invasive
measurements. During CRT implantation the optimal AVD and VVD are determined by
left ventricular dP/dt measurements using the Flexstim II
pacemaker-/computersystem. The measurements during resting conditions are
compared to those during dobutamine infusion (a simulation of exercise).
Study burden and risks
The implanted pacemakerleads are temporarily connected to the external Flexstim
II system. To prevent infection, a maximum implantation duration is
effectuated. The use of the Flexstim II will lead to more accurate and precize
determination of the optimal AVD and VVD and therefore better acute
hemodynamics.
The optimization procedure during dobutamine infusion will add approximately 30
minutes to the implantation procedure. The echocardiogram during dobutamine
infusion also takes approximately 30 minutes. Dobutamine is not an experimental
drug and the safety of the infusion protocol is proven during the use in stress
echocardiograms, stress MRI*s and myocardial perfusion imaging. Potential side
effects are usually well tolerated and a slower infusion rate or cessation of
infusion will in general revert these side effects.The study results will not
be implemented in the study subjects but might in the future, after further
research, have therapeutic benefit for the subjects.
To measure the dP/dt in the coronary sinus, a wire with pressure sensor is
temporarily inserted in this vein. The results can potentially lead to an
advantage for future CRT patients.
Transthoracic echocardiography is a safe and noninvasive procedure without
adverse side effects.
Postbus 85500
3508 GA Utrecht
Nederland
Postbus 85500
3508 GA Utrecht
Nederland
Listed location countries
Age
Inclusion criteria
Indication for Cardiac Resynchronization Therapy according to the current international guidelines. (See research protocol: chapter 5.2)
Exclusion criteria
Criteria for the complete study: (see also research protocol chapter 5.3)
-Contraindications for implantation of a CRT device;
-Age <18 years or incapacitated adult;
-Participation in another clinical study that prohibits any procedures other than standard;
-Pregnancy;
-Severe aortic stenosis with a valve area <1,0 cm2 or aortic valve replacement in history.;Specific criteria for the infusion of dobutamine (see research protocol chapter 5.3 and 6.2.1):
-Significant abnormalities on coronary angiogram or myocardial perfusion scan (part of standard procedure before CRT implantation) that are not treated by coronary artery bypass graft or percutaneous coronary intervention;
-Atrial fibrillation with a fast ventricular response (heart rate >100 bpm);
-Baseline heart rate <10 beats per minute below target heart rate;
-Sinus bradycardia <40 beats per minute at baseline;
-Open operation wound for more than 3 hours before start of dobutamine infusion (only applies to dobutamine infusion during device implantation);
-Contraindications for dobutamine (baseline systolic blood pressure >180 mmHg or <80 mmHg, hemodynamic significant left ventricular outflow tract obstruction, aortic aneurysm, aortic dissection);
-Insufficient image quality during echocardiography at rest (only applies to dobutamine stress echocardiography);
-Experienced secondary endpoint (side effect) during dobutamine stress echocardiography (only applies to dobutamine infusion during device implantation).
Design
Recruitment
Medical products/devices used
Followed up by the following (possibly more current) registration
No registrations found.
Other (possibly less up-to-date) registrations in this register
No registrations found.
In other registers
| Register | ID |
|---|---|
| CCMO | NL22307.041.08 |