الفهرس | Only 14 pages are availabe for public view |
Abstract SUMMARY ight ventricular apical lead placement became standard practice secondary to the ease of site accessibility and lead stability. Long-term RVA pacing is detrimental causing reduced LV function and adverse cardiac remodeling, as well as increased incidence of HF, AF and death. Patients with a reduced baseline LVEF and high amount of RVA pacing are at highest risk. CRT has changed the clinical management of patients with drug-refractory HF. Various randomized controlled trials have shown significant improvements in symptoms, LV function and long-term survival. The optimal placement of an LV lead in a tributary of the CS to be coincident with the latest activated areas of the left ventricle is one of the most challenging technical aspects of CRT device implantation, this maximizes the haemodynamic benefits of CRT and provides superior long-term outcome. The aim of the study is the assessment of CS lead function (pacing threshold, sensing threshold and lead impedance) in patients with newly implanted CRT systems over a follow up period of 6 months to determine possibility of using LV pacing instead of RV pacing in patients requiring percutaneous permanent cardiac pacing for symptomatic bradycardia and having normal LV function. This is a prospective study included 50 consecutive patients with congestive heart failure who received CRT systems at Ain Shams university hospitals from September 2013 to February 2014 according to the latest ESC guidelines. Their ages ranged from 22 to 77 year old with mean 55.04 ± 12.62 years including 90% males. Thirty-three (66%) patients had DCM and 17 (34%) had ICM. All patients were receiving maximally tolerated medical therapy for heart failure. The mean EF was 25.02 ± 6.9 %, LVEDD 70.90 ± 9.7. LV lead function parameters including LV lead impedance, R wave and pacing threshold were stable over 6 month follow up and parameters were comparable to the RV lead. Patients who received LV pacing via the posterolateral branch had a lower BMI and lower LV impedance at 2 week follow up versus those who received LV pacing via other branches. LV lead function parameters were similar between patients with and those without viability at implantation site. LV lead function parameters were comparable between patients with DCM versus those with ICM at all-time points. The long-term performance of CS lead revealed a stable course over 6 month follow up. |