Despite the convincing effect of CRT on survival, symptoms, and LV function (2,3,4) as much as 30-40 % of the patients do not benefit clinically from the treatment, so-called non-responders (5,6). Annually around 600 CRT-systems are implanted in Denmark and about 3000 patients live with a CRT. The risk of complications associated with CRT-treatment is considerable (7), and a conservative estimate of the expenses for implanting a CRT-device is DKK 80.000. Consequently, the costs of CRT in non-responders are high, both for the patients and for the health economy.