The objective of this study is to compare the benefit of CRT-therapy in patients with a QRS-complex of 120-150 ms to patients with a QRS-complex of > 150 ms within 12 months. A benefit is defined as change in quality of life and change in physical ability.
The purpose of this study is to compare the benefit of cardiac resynchronization therapy (CRT)-therapy in patients with a QRS-complex of 120-150 ms to patients with a QRS-complex of > 150 ms.