Tricuspid regurgitation (TR) reduction by transcatheter tricuspid valve repair (TTVR) is associated with an improvement in liver function as well as stabilization of kidney function, making it an attractive option for patients with severe TR and kidney or liver dysfunctions, according to a study published in JACC: Cardiovascular Interventions.
The researchers sought to test their hypothesis that TTVR would result in an improvement in kidney and liver functions in patients presenting with severe TR. Patients undergoing TR using edge-to-edge repair technique (N=126) between March 2016 and June 2018 at the Munich University Hospital were selected for participation in the study. After an initial assessment at baseline, follow-up examinations with blood tests were performed at 30 days and 6 months. Grading of TR was conducted in 4 stages: mild (1+), moderate (2+), severe (3+), and massive (4+). Kidney function was assessed with serum creatinine and urea levels and the glomerular filtration rate. Liver function was assessed using levels of aspartate transaminase, alanine transaminase, gamma-glutamyl transpeptidase, and bilirubin levels. Analyses were performed using the Chi-square test, paired Student t-test, and Wilcoxon test.
Over the study period, patients underwent isolated TTVR (n=59) and combined transcatheter mitral and tricuspid valve repair (n=67) for severe TR. Out of 126 patients at baseline, 110 (87.3%) survived at 6 months, with a median time to death of 57.5 (26.0-72.5) days. Those who died were excluded from the primary analysis. Except for a reduction in the TR grade, there was no significant change in echocardiogram parameters at 30 days (TR grade above 3 in 96.2% at baseline vs 17.9% at 30 days; P <.001). TR grade was 2+ or less in 67 (85.9%) survivors at 6 months. Decreases in right ventricular and end-systolic and end-diastolic areas were observed over the study period (17.3 to 16.7 cm², P =.03, and 27.6 to 24.7 cm², P =.002, respectively). With regard to renal and liver function tests, there was no difference between baseline and 30 days, except for a reduction in the bilirubin level (1.2 vs 1.0 mg/dl, P =.017). Renal function tests remained stable at 6 months. A significant improvement in liver function was observed only in alanine transaminase level (30.7 U/L at baseline vs 24.9 U/L at 6 months, P <.001).
This study was limited by the low absolute number of patients, which likely accounted for a lack of power to evidence significant improvements in kidney and liver functionality tests. Additionally, there were a lack of data regarding factor V and albumin levels as well as a lack of follow-up on some patients.
TTVR is an attractive option for patients with severe TR and dysfunctions of the kidney and liver who are at even higher surgical risks. Longer follow-up time is needed to assess the impact of improvements in kidney and liver function on patients’ prognosis.
Multiple authors acknowledge conflicts of interest; please see full reference for a list of disclosures.
Karam N, Braun D, Mehr M, et al. Impact of transcatheter tricuspid valve repair for severe tricuspid regurgitation on kidney and liver function [published online May 2019]. JACC Cardiovasc Interv. doi: 10.1016/j.jcin.2019.04.018