Portal vein Doppler tracks volume status in patients with severe tricuspid regurgitation: a proof-of-concept study.

Aims: Renal and liver congestion are associated with adverse outcomes in patients with tricuspid regurgitation (TR). Currently, there are no valid sonographic indicators of fluid status in this population. Intra-renal venous Doppler (IRVD) is a novel method for quantifying renal congestion but its interpretation can be challenging in severe TR due to altered haemodynamics. This study explores the potential of portal vein Doppler (PVD) as an alternative marker for decongestion during volume removal in patients with severe TR.

Methods and results: Forty-two patients with severe TR undergoing decongestive therapy were prospectively enrolled. Inferior vena cava diameter, PVD, and IRVD were sequentially assessed during volume removal. Improvement criteria were portal vein pulsatility fraction (PVPF) < 70% and renal venous stasis index (RVSI) < 0.5 for partial improvement, and PVPF < 30% and RVSI < 0.2 for complete improvement. After volume removal, PVPF significantly improved from 130 ± 39% to 47 ± 44% (P < 0.001), while IRVD improved from 0.72 ± 0.08 to 0.54 ± 0.22 (P < 0.001). A higher proportion of patients displayed improvement in PVD compared to IRVD (partial: 38% vs. 29%, complete: 41% vs. 7%) (P < 0.001). Intra-renal venous Doppler only improved in patients with concomitant improvement in severe TR. Portal vein Doppler was the only predictor of achieving ≥5 L of negative fluid balance [area under the ROC curve (AUC) 0.83 P = 0.001].

Conclusion: This proof-of-concept study suggests that PVD is the only sonographic marker that can track volume removal in severe TR, offering a potential indicator for decongestion in this population. Further intervention trials are warranted to determine if PVD-guided decongestion improves patient outcomes in severe TR.