Effects of tricuspid valve surgery on tricuspid regurgitation in patients with hypoplastic left heart syndrome: a non-randomized series comparing surgical and non-surgical cases

Tricuspid regurgitation (TR) remains a significant risk factor affecting the survival of patients with hypoplastic left heart syndrome (HLHS). We performed this study to investigate differences in the clinical course based on the timing of the development of TR and the effects of tricuspid valve surgery (TVS). One hundred and five patients of classic HLHS underwent staged operations from May 1991 to July 2010. Forty-four patients (41.9%) exhibited moderate or greater TR during the follow-up. We defined the early TR group (30 patients, around the first palliative surgery) and the late TR group (14 patients, the later period) based on the timing of the appearance of moderate or greater TR. We performed TVS when moderate or greater TR was detected in 28 patients. The follow-up period was 5.5 +/- 5.1 (plus/minus values are means +/- SD) years (range: 0.01-14.6 years) after the first palliative surgery and 4.9 +/- 4.4 years (range: 0.01-13.3 years) after TVS. The early TR group exhibited poorer survival than the late TR group (42.9 vs 92.9% at 5 years, P = 0.003). However, in the early TR group, the TVS significantly improved survival compared with that observed in the non-TVS cases (52.1 vs 23.3% at 5 years, P = 0.046). The right ventricular ejection fraction (RVEF) significantly decreased (62.7 +/- 11.4 -> 57.2 +/- 12.6% (plus/minus values are means +/- SD), P = 0.040) and the right ventricular end-diastolic diameter (RVDd) became significantly enlarged (27.7 +/- 7.6 -> 36.7 +/- 3.4 mm, P < 0.001) in association with deterioration of the TR degree. TVS significantly improved the degree of TR (2.5 +/- 0.5 -> 1.5 +/- 0.9A degrees, P < 0.001) and RVDd (37.7 +/- 7.4 -> 30.4 +/- 5.0 mm, P = 0.007); however, the RVEF was not improved 1 month after surgery (54.4 +/- 12.1 -> 54.3 +/- 12.4%, P = 0.931) or at the latest follow-up (53.7 +/- 14.9%, P = 0.836). The survival of HLHS patients who develop moderate or greater TR around the time of the first palliative surgery is worse than that of HLHS patients who develop moderate or greater TR at a later time. In this study, TVS for early TR improved survival and decreased right ventricular dimensions during the 4.9-year follow-up period.