Pacing in heart failure: focus on risk stratification and patient selectionfor cardiac resynchronization therapy

This thesis has shown that significant lead-induced TR due to the mechanical presence of an RV-lead though the tricuspid valve was associated with worse long-term prognosis. CRT is one of the main therapeutic breakthroughs in heart failure of the last decade but patients included in landmark trials do not completely mirror patients undergoing CRT in the clinical practice, who are usually older and have more frequently associated comorbidities such as renal dysfunction, diabetes or atrial fibrillation. This thesis shows a beneficial, although limited, effect of CRT also in elderly, in patients with diabetes and CKD stage 4, and therefore suggests that this therapy should not be withheld based on certain co-morbidities or on age alone. Furthermore, it shows that RBBB in patients referred to CRT and favourable RV-function improvement after CRT were associated with CRT outcomes. To improve clinical risk-stratification, this thesis proposed a CRT-SCORE using CRT-specific parameters and showed to be valuable in risk-estimation that may assist clinicians in counseling patients and guide clinical shared decision-making. Finally, novel approaches to optimize patient selection are presented in this thesis. SDI, a 3D-echocardiography LV-dyssynchrony measurement and T1-mapping, a novel CMR-technique to quantify diffuse myocardial fibrosis were significantly associated with CRT outcomes.