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........................................................................................................................................................ Pacemaker implantation is more frequent after valvular than after coronary artery bypass graft (CABG) surgery.477 In clinical practice, an observation period of 37 days is usually applied before implanting a permanent pacemaker473 to allow regression of transient bradycardias. The ideal timing of pacemaker implantation after cardiac surgery remains a topic of controversy, due to the fact that 6070% of patients implanted for SND and up to 25% of those implanted for AVB are not pacemaker dependent at follow-up.473,478 In the case of complete AVB occurring within the first 24 h after valvular surgery and persisting for 48 h, resolution within the next 12 weeks is unlikely and earlier implantation of a pacemaker may be considered.479,480 The same approach appears reasonable for complete AVB with a low rate of escape rhythm.473 The situation in CHD surgery and in children may be different (see section 8.4).

In valvular endocarditis, predictors of AVB after surgery are preoperative conduction abnormalities, Staphylococcus aureus infection, intracardiac abscess, tricuspid valve involvement, and previous valvular surgery.481 In patients with endocarditis and peri-operative AVB, early pacemaker implantation is reasonable, especially when one or more predicting factors are present. In light of the infected state of the patient, intra-operative implantation of an epicardial pacemaker system during valvular surgery may be reasonable despite the absence of solid data on infection rates of epicardial vs. transvenous pacemaker systems.

8.2.2 Pacing after heart transplantation SND is common and leads to permanent pacemaker implantation after heart transplantation in 8% of patients.473 Possible causes of SND include surgical trauma, sinus node artery damage, or ischaemia and prolonged cardiac ischaemic times.482,483 AVB is less common, and is probably related to inadequate preservation of the donor heart.473,483,484 Chronotropic incompetence is always present following standard orthotopic heart transplantation, as a result of loss of autonomic control. As sinus node and AVN function improve during the first few weeks after transplantation, an observation period before pacemaker implantation may allow spontaneous improvement of bradycardia.485 There is general consensus that patients in whom symptomatic bradycardia persists after the third postoperative week may require permanent pacemaker implantation. DDD(R) mode with minimized ventricular pacing in the case of intact AVN conduction is recommended.483

8.2.3 Pacing after tricuspid valve surgery An underestimated aspect of the surgical management of tricuspid valve disease is to address trans-tricuspid pacemaker or ICD leads. Such leads can interfere with the function of a repaired tricuspid valve or tricuspid valve prosthesis. Placing an epicardial RV lead at the time of tricuspid valve surgery is the most straightforward alternative in cases with type II second- or third-degree AVB. There have been doubts about the long-term performance of epicardial leads, but recent data indicate, at least for epicardial LV leads, performance comparable with transvenous leads.486

Ventricular pacing after mechanical tricuspid valve replacement using a coronary sinus lead appears safe and feasible, but only results from small patient cohorts have been published. Procedural success of implantation was 100% in 23 patients; after 5.3 ± 2.8 years, 96% of leads were functional with stable pacing and sensing parameters.487 HBP is emerging as a more physiological method of ventricular pacing and may evolve into a possible solution in patients with AV conduction disease after tricuspid valve surgery. One study investigating 30 patients with HBP after cardiac valve operations reported successful permanent HBP in 93% of these patients.488 This study included 10 patients with tricuspid valve annuloplasty. After replacement by a mechanical valve, transvalvular lead placement is contraindicated, and implanting either a coronary sinus lead for ventricular pacing or epicardial leads, which may be placed minimally invasively, is recommended. To avoid damaging a repaired tricuspid valve or a tricuspid bioprosthesis, the optimal solution in patients needing ventricular pacing after such surgery should not include transvalvular lead implantation. Implanting a coronary sinus lead for ventricular pacing or minimally invasively placed epicardial leads is judged to be the preferred choice. However, as indicated in observational reports, transvalvular lead implantation was used with acceptable results,489 and still may be considered in selected patients after tricuspid valve annuloplasty, other types of repair, and replacement of a tricuspid valve by a bioprosthesis. Performing tricuspid valve replacement in a patient with an existing RV lead, removal of the old RV lead and implantation of an epicardial RV lead should be preferred over sewing in the existing lead between a bioprosthesis and annulus. The reasons are that sewing in the lead may be associated with higher risk of lead failure and, in the case of future need for lead extraction, such a procedure is likely to require open heart surgery, which will be a reintervention with higher operative risk. In cases of tricuspid valve repair with a current annuloplasty ring with an open segment and without concomitant leaflet procedures, an existing RV lead may be left in place without sewing it in between the ring and the annulus. However, even in isolated annuloplasty procedures, an existing RV lead should ideally be removed to avoid future lead-related complications to the repaired tricuspid valve and an epicardial RV lead should be implanted. Particularly in patients not in need of a dual-chamber device, the use of a leadless pacemaker for ventricular pacing may serve as a feasible future alternative after tricuspid valve repair or replacement by a bioprosthesis. However, experience is very limited, and no long-term data are available in this cohort. Crossing a mechanical tricuspid valve with the delivery sheath and a leadless pacemaker is contraindicated. Downloaded from academic.oup.com/eurheartj/article/42/35/3427/6358547 by guest on 07 October 2026