National Tunisian Study of Cardiac Implantable Electronic Devices: Design and Protocol for a Nationwide Multicenter Prospective Observational Study.

BACKGROUND: In Tunisia, the number of cardiac implantable electronic devices (CIEDs) is increasing, owing to the increase in patient life expectancy and expanding indications. Despite their life-saving potential and a significant reduction in population morbidity and mortality, their increased numbers have been associated with the development of multiple early and late complications related to vascular access, pockets, leads, or patient characteristics. OBJECTIVE: The study aims to identify the rate, type, and predictors of complications occurring within the first year after CIED implantation. It also aims to describe the demographic and epidemiological characteristics of a nationwide sample of patients with CIED in Tunisia. Additionally, the study will evaluate the extent to which Tunisian electrophysiologists follow international guidelines for cardiac pacing and sudden cardiac death prevention. METHODS: The Tunisian National Study of Cardiac Implantable Electronic Devices (NATURE-CIED) is a national, multicenter, prospectively monitored study that includes consecutive patients who underwent primary CIED implantation, generator replacement, and upgrade procedure. Patients were enrolled between January 18, 2021, and February 18, 2022, at all Tunisian public and private CIED implantation centers that agreed to participate in the study. All enrolled patients entered a 1-year follow-up period, with 4 consecutive visits at 1, 3, 6, and 12 months after CIED implantation. The collected data are recorded electronically on the clinical suite platform (DACIMA Clinical Suite). RESULTS: The study started on January 18, 2021, and concluded on February 18, 2023. In total, 27 cardiologists actively participated in data collection. Over this period, 1500 patients were enrolled in the study consecutively. The mean age of the patients was 70.1 (SD 15.2) years, with a sex ratio of 1:15. Nine hundred (60%) patients were from the public sector, while 600 (40%) patients were from the private sector. A total of 1298 (86.3%) patients received a conventional pacemaker and 75 (5%) patients received a biventricular pacemaker (CRT-P). Implantable cardioverter defibrillators were implanted in 127 (8.5%) patients. Of these patients, 45 (3%) underwent CRT-D implantation. CONCLUSIONS: This study will establish the most extensive contemporary longitudinal cohort of patients undergoing CIED implantation in Tunisia, presenting a significant opportunity for real-world clinical epidemiology. It will address a crucial gap in the management of patients during the perioperative phase and follow-up, enabling the identification of individuals at particularly high risk of complications for optimal care. TRIAL REGISTRATION: ClinicalTrials.gov NCT05361759; https://classic.clinicaltrials.gov/ct2/show/NCT05361759. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR1-10.2196/47525.

Is there a need for more than one left ventricular lead in some patients?

Cardiac resynchronization therapy (CRT) is an effective treatment of heart failure in selected patients. However, with conventional CRT, notable left ventricular (LV) reverse remodelling is achieved in only 60-70% of patients. This lack of effect of CRT might be due to incomplete resynchronization. In some patients, the paced activation front arising from a single LV electrode is unfavourable, possibly resulting in suboptimal resynchronization. Dual-site LV CRT has theoretical advantages in faster and more physiological LV activation. Some clinical evidence supports dual LV pacing. Nevertheless, a clear benefit of this pacing modality in patients chronically implanted is still unproved. A randomized study comparing single- and dual-site LV pacing, the Triple-Site Cardiac Resynchronization study of Patients with Heart Failure (TRUST CRT) is still ongoing.

Incidence, risk factors, and outcome of traumatic tricuspid regurgitation after percutaneous ventricular lead removal.

OBJECTIVES: This study sought to evaluate the incidence, risk factors, and outcome of traumatic tricuspid regurgitation (TTR) induced by percutaneous removal of chronically implanted transvenous leads. BACKGROUND: Although lead removal using modern tools has been shown to be highly effective and safe, TTR has not been systematically evaluated. METHODS: All patients undergoing ventricular lead removal at our center were studied. Lead removal was performed by simple traction, laser sheath, and/or lasso technique. Presence of a new TTR after removal was assessed by transthoracic echocardiography. Pre-defined clinical and technical parameters were studied for their association with TTR. Patients were followed up by outpatient visits. RESULTS: We removed 237 ventricular leads in 208 patients. Median time from lead implantation was 46.4 months (range 0.7 to 260.5 months). A TTR occurred in 19 patients (9.1%), severe in 14. Three independent risk factors of TTR were found: use of laser sheath (p = 0.004), use of both laser sheath and lasso (p = 0.02), and female sex (p = 0.02). After a follow-up of 4,130 person-months (median 17.9 months), 5 TTR patients were medically treated for new right-sided heart failure symptoms, 2 had undergone surgical repair of the tricuspid valve, and 6 had died (2 from heart failure and 4 from noncardiac causes). Right-sided heart failure occurred only in patients with severe TTR. CONCLUSIONS: This study found that TTR is not uncommon after percutaneous lead removal. It is strongly associated with the use of additional tools beyond simple traction and also with female sex. In the long term, right-sided heart failure is frequent in patients with severe TTR.

Right ventricular apex pacing: is it obsolete?

Clinical trials in patients with pacemakers for sinus node dysfunction or atrioventricular block have highlighted the fact that desynchronization of ventricular contraction induced by right ventricular apical pacing is associated with long-term morbidity and mortality. These clinical data confirm pathophysiological results indicating that right ventricular apical pacing causes abnormal ventricular contraction, reduces pump function and leads to myocardial hypertrophy and ultrastructural abnormalities. In this manuscript, we discuss the clinical evidence for the adverse and beneficial effects of various right ventricular pacing sites, left ventricular pacing sites and biventricular pacing. We also propose a decisional algorithm for pacing modalities, based on atrioventricular conduction, left ventricular function and expected lifespan.

[Doppler tissue imaging contribution in the study of diastolic dysfunction in hemodialysis patients]. / Place du Doppler tissulaire myocardique dans l'etude de la dysfonction diastolique ventriculaire gauche chez les malades hemodialyses.

BACKGROUND: Doppler echocardiography is currently the main tool permitting the diagnosis and the characterization of the stages of diastolic dysfunction. AIM: The purpose of this study is to precise the contribution of Doppler tissue imaging in the study of diastolic function and to identify the parameters having the most discriminating power of diastolic dysfunction in hemodialysis patients. METHODS: Conventional Doppler echocardiography study implies left ventricular diastolic function from: Doppler transmitral flow (E/A, isovolumic relaxation time (TRIV), deceleration of mitral E-wave time (TDE), duration of A wave), color M-mode flow propagation velocity (Vp); The study of pulmonary venous flow (S/D, Systolic fraction (FS) and duration of pulmonary venous A wave); The annulus Doppler Tissue Imaging (Ea/Aa, E and A waves durations, VTI of E and A); and finally combined indexes (ratio of peak E-wave velocity to Vp (E/Vp), difference in duration between pulmonary venous and mitral flow A wave (Ap-Am) and ratio of peak mitral and annulus E-wave velocities (E/Ea). RESULTS: Left ventricular diastolic dysfunction is found in 88% of the 50 haemodialysis patients: abnormal relaxation pattern 56%, pseudo-normal pattern 28% and restrictive pattern 4%. The parameter Vp discriminates normal patterns. The parameters TRIV, S/D and FS characterise abnormal relaxation. Ea/Aa ratio characterises pseudo-normal pattern and E/A ratio restrictive pattern. Discriminating analysis allows a correct classification of 100% of pseudo-normal pattern patients with 3 variables: Ea/Aa, FS and Vp or E/Vp. Doppler parameters which discriminating power is significant (p < 0.0001) are, in decreasing order: E/A, Ea/Aa, TRIV, Vp, FS, S/D, E/Vp and TDE. CONCLUSION: DTI contributes mainly in the characterization of stage II diastolic dysfunction patients and allows in association with pulmonary venous flow parameters (Ap-Am) and combined indexes (E/Vp et E/Ea) an accurate appreciation of left ventricular filling pressures.