Cardiac Resynchronization Under Electroanatomical Guidance After Failure of Primary Implantation

• Patient with indication for implantation of a classic multisite pacemaker;
• New York Heart Association II/IV patient despite optimal medical treatment;
• Patient with left ventricular ejection fraction ≤35%;
• Patient with a widened QRS > 120ms;
• Patient with at least one lateral coronary sinus vein visualized on angiography during the 1st procedure (if performed);
• Patient with failure of resynchronization via the endovenous route due to difficulty in accessing the coronary sinus or instability in the coronary sinus;
• Patient having been informed and having signed an informed consent form;
• Patient able to understand the information related to the study (absence of linguistic, psychological, cognitive problem, etc.), and to complete questionnaires.

Exclusion Criteria:

• Patient with resynchronization failure due to occlusion of the superior vena cava;
• Patient with no usable lateral coronary sinus vein;
• Patient with a life expectancy \< 3 months;
• Patient wearing a vena cava filter;
• Patient with active sepsis;
• Pregnant or likely to be pregnant (of childbearing age, without effective contraception) or breastfeeding;
• Patient participating in another clinical trial, or in a period of exclusion from another clinical trial;
• Patient not benefiting from a social security scheme.