Pacemaker-induced tricuspid regurgitation is uncommon immediately post-implantation.

BACKGROUND: Prior studies report permanent pacemaker (PPM)-induced tricuspid regurgitation (TR) in up to one third of cases late post-implantation. We sought to assess the extent of immediate PPM-induced TR.

METHODS: Forty patients undergoing PPM implant were prospectively enrolled. Patients with pre-existing moderate or severe TR or an RVSP >50 mmHg were excluded. Pre- and immediate post-implantation transthoracic echocardiography (TTE) analyzed TR grade according to established methods. 3D TTE was utilized to determine lead position in relation to tricuspid leaflets as well as lead mobility across the TV.

RESULTS: Of 40 patients, four were excluded due to baseline moderate TR (n = 3) or RVSP >50 mmHg (n = 1). In the remaining cohort (n = 36), immediate post-implantation TTE showed no increase in TR grade in 30 patients (83%), whereas a one-grade increase from no/trace to mild occurred in six (17%) others. In no patient did immediate moderate or severe TR develop. Exclusive RV pacing was present in 47% of the patients; however, only two of the six patients with increased TR were paced. 3D TTE identified lead position in 92% of the cases-more than 50% of the cases showed RV lead distribution in the middle or post eroseptal commissure of the TV. Lead immobility was seen in only three of the six patients with increased TR.

CONCLUSIONS: These findings show that significant PPM-induced TR is uncommon immediately post-implantation and, when it occurs, causes no greater than mild TR. RV pacing and lead mobility do not correlate with worsening of TR. 3D TTE is highly reliable at identifying lead position.