Abstract 3185: Impact of Left Ventricular Lead Position on Left Ventricular Function and Remodelling after Long Term Follow-Up with Cardiac Resynchronization Therapy Using Myocardial Deformation Imaging
Aims. This study sought to assess if myocardial deformation imaging (MDI) allows definition of an optimal left ventricular (LV) lead position for improved effectiveness of cardiac resynchro-nisation therapy (CRT).
Methods. MDI based on tracking of acoustic markers within 2D echo images (GE Ultrasound) was performed in 47 heart failure patients (57±9 years, 28men) at baseline and 10 (±3) months follow up. Ejection fraction (EF), LV end-systolic volume (LVESV) and end-diastolic volume (LVEDV) were determined before and after CRT. In a 17 segment LV model the segment with latest peak systolic circumferential strain was determined. Additionally, the segment with maximal temporal difference of peak strain between pre- and post-CRT was defined as the segment with greatest benefit of CRT and assumed to be location of the LV-lead. Optimal LV lead position was defined as concordance or immediate neighbouring of the segment with latest myocardial deformation prior to CRT and the segment with maximal temporal difference of peak strain pre- and post-CRT. After CRT implantation a biplane fluoroscopy in orthogonal views (LAO 60°,RAO 30°) was acquired to determine the anatomical location of the LV lead.
Results. 25 patients showed optimal, 22 patients non-optimal position of the LV lead based on this definition. Preoperatively EF, LVESV and LVEDV were similar in both groups. After 10 (±3) months there was greater increase of EF (ΔEF 11±3 vs. 7±3%, p<0.001) and greater decrease of LVESV (Δ LVESV 27±7 vs. 17±5ml, p<0.001) and LVEDV (Δ LVEDV 30±7 vs. 21±6ml, p<0.001) in the optimal compared to the non-optimal LV lead position group. In 33 patients the anatomical LV lead position could be determined by the fluoroscopy, 89% of the LV lead placements were in agreement with the echocardiographic analysis.
Conclusions. MDI is a new 2D based imaging modality which allows detailed analysis of the myocardial contraction sequence.Optimal LV lead position in CRT defined by MDI with the segment with latest contraction prior to CRT results in greater improvement in LV function and remodelling than non-optimal LV lead position.