Herzinsuffizienz und kardiale Resynchroninsationstherapie (CRT)
Rolle der 3D-Echokardiographie
Fakultät für Medizin
Despite progress in the treatment of heart failure the five year mortality still remains over 50%. Cardiac resynchronization therapy (CRT) has evolved as the treatment of choice for patients with symptomatic heart failure, left bundle branch block/QRS widening (>/= 120 ms) and severely reduced systolic left ventricular (LV) function despite optimal medical therapy. Large studies have shown that CRT not only improves quality of life and LV systolic function but also leads to a reduction in mortality. Nevertheless up to one third of patients, so called non-responders do not symptomatically respond to this therapy. the exact reason for lack of response are still unclear. If one takes into account potential suboptimal LV lead placement, electrical latency during LV stimulation and slowed conduction due to scars near the LV pacing site, all possibly contributing to a reduced response to CRT, an individualized approach to programming CRT systems, with the possibility of pre-activation of either one of the ventricular leads, is intriguing. The possibility to assess LV dyssynchrony has made threedimensional echocardiography attractive for optimization of cardias resynchronization therapy. A sophisticated threedimensional echocardiographic optimization protocol of biventricular pacemakers, integrating this novel LV dysynchrony index, has been developed and acute and longterm results avaluated in patients with CRT. In the first patient cohort we could demonstrate, that an individualized echocardiographic optimization with the integration of threedimensional indices into the optimization protocol significantly improved LV function in CRT compared to empiric VV interval programming. In a randomized follow-up study we could show that in addition to avutely improving LV function and volumes, after three months the treedimensional echocardiographic optimization protocol led to a significantly increased clinical response rate, a higher increase in EF, associated with a more pronounced reduction of LV dyssynchrony compared to the conventional ECG optimization protocol. Moreover, the prognostic parameters of response to CRT in this optimized patient cohort were evaluated. Non-respnders showed a trend towards higher baseline LV enddiastolic and endsystolic volumes than responders. This should be considered when selecting patients for CRT, as once a certain degree of adverse mechanical remodeling has occurred, electrical resynchronization may no longer be abl3e to reverse this process. Considering the significant and burdening non-responder rate to CRT, both a careful patient selection process before CRT including echocardiographic evaluation of LV volumes and dyssynchrony, as well as a conscientious optimization protocol of biventricular pacemakers is relevant.
Further more, mitral regurgitation (MR) is a common associated problem in patients with heart failure worsening the clinical outcome in these patients. Percutaneous repair of the mitral valve is an alternative treatment especially in heart failure patients that are at high risk for surgery. We could show that intraprocedural 3D volume transesophageal echocardiography helps during the crucial step of the percutaneous edge-to-edge repair of the mitral valve by improved assessment of leaflet insertion in the clip and has the potential to reduce the rate of clip detachment and thgus redurrence of significant mitral regurgitation. Finally, baseline mitral valve morphology and -dynamics may influence the success rate of mitral valve clipping. The established threedimensional echocardiography derived normal reference values for the mitral appartus geometry provide the basis for future studies on the search of prognostic parameters of successful mitral valve clipping. «
Despite progress in the treatment of heart failure the five year mortality still remains over 50%. Cardiac resynchronization therapy (CRT) has evolved as the treatment of choice for patients with symptomatic heart failure, left bundle branch block/QRS widening (>/= 120 ms) and severely reduced systolic left ventricular (LV) function despite optimal medical therapy. Large studies have shown that CRT not only improves quality of life and LV systolic function but also leads to a reduction in mortal... »