Introduction: Nowadays the cardiac resynchronization therapy is one of the most beneficial among the methods of heart failure treatment. Nevertheless there are too much problems unsolved yet how to make it more effective.
Objectives: The aim of our study was to evaluate our experience of CRT in CHF patients with sinus rhythm and permanent atrial fibrillation (AF) in order to primary localization of left ventricle electrode.
Methods: 31 patients with CHF and the average heart rate below 90 bpm have been observed: 10 patients with permanent AF and 21 on sinus rhythm. CRT-P was implanted into 26 and CRT-D into 5 patients. All patients underwent 6 minutes walk test. Well response to CRT was considered in patients with an increase in 6 minutes walk test more than 40 m and EF more than 5%. The measurement of EF by echocardiography and 24-hour ECG-monitoring were done before and after CRT implantation. The percentage of BV pacing calculation has been done in both groups by ECG-monitoring. If patient had less than 90% BV complex and his "fusion" beats had less hemodynamic response as BV complex we recommend ablation of AV node.
Surgical aspects of the implantation: in 26 cases the left ventricular electrode has been implanted in lateral cardiac vein with acceptable parameters, in 4 cases – in posterior vein and in 1 case we had only choice to deliver it into anterior vein closer to the apex.
Results: There were 10 responders (47%) in group of sinus rhythm and 6 responders (60%) in group of AF (p=0,7). The mean time of follow-up was 2 years. There was 1 SHD in group of AF and 3 deaths in group of sinus rhythm (2 SHD and 1 HF). All SHD cases occurred in patients with CRT-P. There was one death in group of patients of sinus rhythm because of CHF increasing. That was the patient with left electrode located close to apex. In other patients the pacing data has been staying on acceptable level in all period of follow-up. 3 of 10 patients with permanent atrial fibrillation had <90% BV complexes. In one patient “fusion” complexes were the same doppler VTI as BV complexes and the amount of BV and fusion complexes was more than 90%. For 2 patients the ablation of AV-node was recommended.
Conclusions: CRT effects in patients with sinus rhythm and permanent AF are mostly comparable especially in first year of follow-up. The ablation of AV node in patients with AF is more helpful if percentage of BV pacing on drug therapy is lower then 90%. The best benefit of CRT may be reached by left electrode implantation in lateral or posterior cardiac veins.