Abstrakt
Introduction: Usefulness of cardiac resynchronization therapy
(CRT) in congenital heart disease (CHD) has so far not been demonstrated.
Methods: 8 pts after surgery for CHD with systemic right (N = 6) or left (N = 2) ventricular dysfunction and spontaneous (bundle branch block, N = 2) or conventional DDD pacing induced (3rd degree AV block, N = 6) systemic ventricular conduction delay aged 6.3-29.2 yrs underwent biventricular pacemaker implantation/ upgrade using epicardial (N = 7) or transvenous (N = 1 ) systemic ventricular leads and were followed-up for a median of 4.5 mo.
Results: There were no procedure related complications. Following biventricular pacing QRS duration decreased from 158 +- 24 to 111 +- 20ms (p < 0.005), systemic ventricular ejection fraction
(radionuclide ventriculography) increased from 41 +- 8 to 48 +- 5%, systemic AV valve regurgitation dv/dt from 37 +- 7 to 54 +- 12 m/s 2
(p < 0.05 for both) and systemic ventricular filling period from 43 +- 8 to 48 +- 8% of respective R R interval (p < 0.005). A rate dependent increase in arterial pulse pressure ranging from a mean of 6.2% at 50% (pNS) to 18.0% at 80% (p < 0.05) of calculated maximum age related heart rate was observed during acute hemodynamic testing after implantation.
Conclusion: CRT is feasible in CHD with the failing right or left systemic ventricle and improves systemic ventricular filling, ejection fraction and pulse pressure over short-term follow-up. Long-term benefit of this new heart failure therapy in terms of reverse remodeling needs to be established.