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............................................................................................................................................................................. presence of multiple RV leads.45,46,49,445,642,685,697,709,728,730732 The issue of lead interference with bioprosthetic tricuspid valves or after annuloplasty or repair is debated. Furthermore, there is no firm evidence supporting that pacing-induced RV dyssynchrony significantly contributes to tricuspid regurgitation. A recent study randomizing 63 patients to pacing lead positions in the RV apex, RVS, or LV pacing via the coronary sinus did not affect the development of tricuspid regurgitation.734 The diagnostic work-up of CIED lead-related tricuspid regurgitation based on clinical, haemodynamic, and in particular echocardiographic (2D, 3D, and Doppler) evaluation is often challenging.735 While clear guidance for the management of tricuspid regurgitation in the presence of CIED leads is still lacking, a high level of clinical suspicion is required, not discounting the possibility that worsening HF may be a consequence of the mechanical effect on tricuspid leaflet mobility or coaptation.730 General treatment options include medical therapy aiming to relieve congestion and lead extraction with careful replacement, or use of alternative pacing strategies, such as LV pacing via the coronary sinus or epicardial leads. However, transvenous lead extraction itself carries a risk of damage to the tricuspid valve and, hence, worsening tricuspid regurgitation. While leadless pacing eliminates the need for transvalvular leads, it may still negatively affect tricuspid valve function, potentially due to mechanical interference and abnormal electrical and mechanical ventricular activation.736 Indications for surgical valve repair or replacement in the context of CIED-induced tricuspid regurgitation follow current recommendations based on the presence of symptoms, severity of tricuspid regurgitation, and RV function. When considering tricuspid valve surgery, management of the RV lead should follow the recommendations outlined in section 8.2.3.737 Methods for percutaneous tricuspid repair have recently gained major attention, but evidence in favour of such interventions in the context of lead-related tricuspid regurgitation is still limited.738

10.2.5 Other Increased complication risks have been observed in women (mainly pneumothorax and cardiac perforation) and in those with a low body mass index.354,739 Patients older than 80 years were also found to have a lower risk of lead-related reinterventions compared with patients aged 6079 years (1.0% vs. 3.1%).354 Finally, suboptimal atrioventricular synchrony may lead to the pacemaker syndrome, giving rise to cannon waves caused by simultaneous atrial and ventricular contractions and symptoms of fatigue, dizziness, and hypotension (see section 5). Long-term RV pacing induces a dyssynchronous ventricular activation pattern that may promote progressive LV dysfunction and clinical HF. Strategies to avoid and resolve the adverse effect of RV pacing have been discussed above (section 6).

11 Management considerations

Integrated management of pacemaker and CRT patients, delivered by an interdisciplinary team in partnership with the patient and family, should be adopted in order to deliver comprehensive treatment across the continuum of healthcare (see section 12). The integratedcare approach is indicated in pacemaker and CRT patients to ensure a patient-centred approach and patient involvement in shared decision-making. The integrated-care approach has its origins in the chronic care model developed by Wagner et al.,740 and has the potential to improve clinical and patient outcomes in arrhythmia management741743 (see section 12). Relevant specialists to be included in the interdisciplinary team are included according to the patient’s needs and local service availability (Figure 13).

11.1 Magnetic resonance imaging in

patients with implanted cardiac devices MRI is a frequent requirement in patients with implanted pacemakers. It may cause adverse effects such as inappropriate device function due to device reset or sensing problems, interaction with the magnetic reed switch, induction of currents resulting in myocardial capture, heating at the lead tip with changes in sensing or capture thresholds, or lead perforation. Risk factors for adverse events with MRIs are listed in Supplementary Table 19. Currently, most manufacturers propose devices that are MRI conditional. It is the entire CIED system (i.e. combination of generator and leads, which need to be from the same manufacturer) that determines MRI conditionality, and not the individual elements. MRI scans may be limited to 1.5 T and a whole-body specific absorption rate (SAR) <2 W/kg (head SAR <3.2 W/kg), but some models allow 3 T and up to 4 W/kg whole-body SAR. The manufacturer may specify an exemption period (usually 6 weeks) after implantation, but it may be reasonable to perform an MRI scan earlier if clinically warranted. There is ample evidence that MRIs can be performed safely in nonconditional pacemakers, as long as a number of precautions are taken.744746 In 2017, the Heart Rhythm Society published an expert consensus statement on MRIs in patients with CIEDs, which was developed with and endorsed by a number of associations including the EHRA and several radiological associations.745 For detailed recommendations on appropriate workflow and programming, see Supplementary Tables 20, 21, and 22 and Supplementary Figure 2. When leads are connected to a generator, the latter component absorbs part of the energy and dissipates heat via the large surface area. Abandoned transvenous leads are prone to heating of the lead tip by 10C as shown by an in vitro study.747 It is, however, difficult to extrapolate results from experimental models to the in vivo setting. No adverse events were reported from four series totalling 125 patients with abandoned transvenous leads.748751 The largest study reported 80 patients749 who underwent 97 scans (including the thoracic region), limited to an SAR <1.5 W/kg. Half of the cohort had measurement of troponin levels before and after the scan, without any significant changes. Therefore, 1.5 T MRI scans (limited to SAR <1.5 W/kg) may be considered in selected patients, taking into account the riskbenefit ratio, particularly if the scans are extrathoracic and patients are not pacemaker dependent. Epicardial leads connected to a generator result in a 10C increase in temperature during in vitro testing, and by as much as 77C with abandoned epicardial leads.747 Data from 23 patients with epicardial leads have been reported,749752 including 14 patients with abandoned epicardial leads,749751 without any adverse effect of MRI scans. Given the paucity of data related to safety in patients with epicardial leads, lead adaptors/extenders, or damaged leads, recommendations cannot be made at this stage regarding MRIs in these patients. Downloaded from academic.oup.com/eurheartj/article/42/35/3427/6358547 by guest on 07 October 2026