[Infections in interventional electrophysiology]. / Infections en rythmologie interventionnelle.

The implantation of pacemakers and defibrillators carries the highest risk of infection in interventional electrophysiology. The use of implantable cardiac devices is continually increasing with almost 2 million devices implanted worldwide each year. The recipients' profile may also be associated with an increased risk of infection. Several measures can be implemented to reduce the risk of device-related infection. Systematic antibiotic prophylaxis has proven to be beneficial provided that prescription modalities are respected, especially with respect to the selection of the appropriate molecule and timing of administration prior to the procedure. Despite all the precautions taken during surgery (asepsis, prophylactic antibiotic therapy….) the estimated rate of peri-procedural infection is around 2%. Device related infections are associated with a high rate of morbidity and mortality as well as substantial healthcare costs. Staphylococcus aureus (SA) and epidermidis (SE) are the pathogenic agents involved in most cases. Prevention is crucial given the difficulties in treating such infections because of the near-systematic need to remove the device and antibiotic resistance. Leadless pacemakers and subcutaneous defibrillators are potential alternatives to implantable endocardial devices, albeit with certain limitations. A group of experts has recently issued consensus paper on the prevention, diagnosis and treatment of infections associated with endocardial implantable cardiac devices.

[Transcatheter aortic valve implantation and conduction disturbances]. / Implantation percutanée de valve aortique et troubles conductifs.

Transcatheter aortic valve implantation (TAVI) is currently becoming the treatment of choice for patients with calcific aortic stenosis. Despite several technical improvements, the incidence of conduction disturbances has not diminished and remains TAVI's major complication. These disturbances include the occurrence of left bundle branch block and/or high-grade atrioventricular block often requiring pacemaker implantation. The proximity of the aortic valve to the conduction system (conduction pathways) accounts for the occurrence of these complications. Several factors have been identified as carrying a high risk of conduction disturbances like the presence of pre-existing right bundle branch block, the type of valve implanted, the volume of aortic and mitral calcifications, the size of the annulus and the depth of valve implantation. Left bundle branch block is the most frequent post TAVI conduction disturbance. Whereas the therapeutic strategy for persistent complete atrioventricular block is simple, it becomes complex in the presence of fluctuating changes in PR interval and left bundle branch block duration. The QRS width threshold value (150-160 ms) indicative of the need for pacemaker implantation is still being debated. Although there are currently no recommendations regarding the management of these conduction disturbances, the extension of TAVI indications to patient at low surgical risk calls for a standardization of our practice. However, a decision algorithm was recently proposed by a group of experts composed of interventional cardiologists, electrophysiologists and cardiac surgeons. There are still uncertainties about the appropriate timing of pacemaker implantation and the management of new onset left bundle branch block.

[Assessment of adherence to antihypertensive drugs in patients with resistant hypertension receiving optimal treatment]. / Évaluation de l'adhérence aux médicaments antihypertenseurs chez des patients avec hypertension artérielle résistante recevant un traitement optimal.

OBJECTIVES: The primary objective was to estimate the proportion of non-adherence to antihypertensive drugs in patients with an apparently resistant hypertension despite optimal medical treatment. The secondary objective was to identify related factors to poor adherence. METHODS: Monocentric, prospective and observational study, including consecutive patients, managed for an apparently resistant hypertension between January 2014 and December 2017, with an ambulatory blood pressure measurement (ABP) in the past year and a thorough etiological work up in the 2 past years. Hypertension was considered resistant if the daytime ABP was ≥ 135/85mmHg and/or the 24hours ABP≥to 130/80mmHg, despite 4 antihypertensive medications at optimal doses. Adherence to treatment was assessed by the eight-item Morisky Scale (MMAS-8). RESULTS: We enrolled 386 patients, with a mean age of 64.6 years, and 48.2% of men. The mean office blood pressure, 24hours and daytime APB were 178.6/101.3mmHg, 164.4/97.2mmHg and 170.5/99.7mmHg respectively. The proportions of low, medium and high adherence were 24.5%, 47.6% and 27.9% respectively. Associated-factors with poor adherence were female sex, low education level, celibacy, polypharmacy and lack of home self-blood pressure monitoring. CONCLUSION: Over two out of three patients with an apparently resistant hypertension under optimal treatment were partially or fully nonadherent to treatment in our study. Assessment of adherence would be systematic in these patients before implementing complex investigations or non-pharmacologic invasive procedures.

[New energy sources for ablative methods]. / Nouvelles sources d'énergie dans les méthodes ablatives.

Radiofrequency current is the reference energy source for endocavitary ablation of arrhythmias. It is particularly well adapted for the ablation of focal arrhythmogenic substrates such as accessory pathways or foyers of automatism. Technological advances have made the lesions larger but the extension of the indications of percutaneous ablation to more complex substrates such as atrial fibrillation have justified the evaluation of alternative energies. The production of linear transmural lesions or deeper lesions which respect the parietal myocardial architecture and endocardial structure are a challenge for these energies. The capacity of functional mapping specific to cryogenics has provided this energy source with a clinical application for ablation of high risk structures whereas other energies, despite the chronicity of their experimental evaluation, are still at the stage of preliminary clinical trials with the sophisticated catheters in special indications.