Background: Tricuspid regurgitation (TR) has been associated with cardiac rhythm device (CRD) implantation with intracardiac lead insertion. However, data on the incidence of postdevice TR are limited and largely from retrospective studies. We hypothesized that permanent lead implantation would be associated with an increase in TR. Methods: We prospectively included consecutive patients with a clinical indication for CRD. Patients underwent transthoracic echocardiography 1 month before and 1 year after CRD implantation. Results: A total of 328 patients were prospectively enrolled (69 ± 15 years, 38% female). Echocardiograms before and 1 year after CRD were available in 290 patients (15 died, 23 lost to follow-up). Compared with baseline, there was a significant change in TR grade 1 year after CRD insertion (no/trivial TR: 66% vs 29%; mild TR: 29% vs 61%; moderate TR: 3% vs 8%; severe TR 2% vs 2%; P < 0.001 for an increase in TR by at least 1 grade). Compared with baseline, there was a higher prevalence of moderate or severe TR in the 247 patients with CRD without cardiac resynchronization therapy (4% vs 10%, P = 0.004), but no progression in the 43 patients who received cardiac resynchronization therapy (14% vs 11%, P = 1). Multivariable analysis in the patients with less than moderate TR at baseline (n = 274) showed that only a history of atrial fibrillation was independently associated with progression to moderate or severe TR after correction for baseline TR grade (P = 0.013). Conclusions: One year after endocardial lead insertion, there was a 5% increase in the prevalence of moderate or severe TR, which may be clinically relevant.