Cardiac resynchronisation therapy

Multi-centric, prospective treatment study (German Medical Devices Act (MPG))

> 80 patients, including children

May 2007

Duration of study: 2nd quarter 2007 to 2nd quarter 2014
End data for recruitment: 4th quarter 2011

• To provide evidence of the effectiveness of cardiac resynchronisation therapy with bi-ventricular stimulation in terms of improved ventricular function and hence improved exercise capacity and quality of life
• To isolate predictive parameters for successful cardiac resynchronisation therapy in patients with congenital heart defects
• To analyse the pathological mechanisms that contribute to disturbance of synchronised contraction/relaxation patterns
• To produce guidelines for measurement of dyssynchrony in congenital heart disease

• Patients with congenital heart defects
• Heart failure of the Morphologically  right or left system ventricle with an absolute ejection fraction of < 40% in the failed ventricle
• NYHA classes II-IV
• Optimal drug therapy for heart failure according to the ESC guidelines
• QRS interval ≥ 120 ms (demonstrated in at least two relevant ECG derivations, depending on existing bundle branch block symptoms)
• Patients with chronic stimulation of the subpulmonary ventricle by a 1- or 2-ventricle pacemaker, which also meets the above-mentioned criteria
• Patients with morphologically right ventricle in system position and significant insufficiency of the systemic atrioventricular valve, if they also meet the criteria listed above

• PTCA, cardiomyoplasty or myocardial infarction / unstable angina pectoris or cerebral insult within the 6 weeks preceding the planned cardiac resynchronisation therapy
• Patients with pulmonary hypertension / Eisenmenger’s syndrome
• Life expectancy < 1 year due to a non-cardiac disease
• Anticipated poor compliance by the patient, e.g. cases of trisomy 21 or any other mental handicap
• Pregnancy and breastfeeding
• Known or persistent abuse of prescription medicines, recreational drugs or alcohol

Within a few days of implantation of the pacemaker, the patients are divided into groups A and B for blind randomised control under a crossover design (to be carried out by KKS). Patients who do not consent to randomisation, or whose haemodynamic condition during the pacemaker’s off phase makes it necessary to activate biventricular pacing, will be placed in group C.

• Group A:  Biventricular pacing for 12 weeks (CRT ON) followed by automatic rhythmicity or the original, conventional biventricular stimulation for 12 weeks (CRT OFF), then returning to biventricular pacing (CRT ON).
• Group B:  Automatic rhythmicity or original conventional biventricular stimulation for 12 weeks (CRT OFF) followed by biventricular pacing (CRT ON).
• Group C:  Continuous biventricular pacing (CRT ON) from the time of implantation for the reasons cited earlier

The treatment is continued for a duration of approximately 18 months, including a final check-up, and involves 6 visits after pacemaker implantation.

• Echocardiography data, incl. 3D echocardiography, will be pseudonymised, placed online and evaluated by the echocardiography cross-sectional project.
• 12-channel ECG / pacemaker testing
• Exercise tests:
  – Ergospirometry data will be made available to cross-sectional project 1
  – 6-minute walk test
• Chemical laboratory tests: electrolyte, renal retention values, pro-BNP or NT-proBNP
• Quality-of-life questionnaires (SF-36/KINDL) will be evaluated by DHZ München.

Explanation of procedure to patients and their legal guardians, signing of consent forms.

• 1st visit: preliminary examination 4 weeks prior to pacemaker implantation
• 2nd visit: within 1 week after pacemaker implantation (CRT) or prior to discharge from hospital
• 3rd to 6th visits: at 12 weeks, 24 weeks, 9 months and 12 months after CRT
• 7th visit: 18 months after CRT

€1,800 per patient

A number of clinics and heart centres all over Germany are taking part in the study. An up-to-date list of these participants can be found here …