Invasieve drukvolumelussen onthullen mechanisme van tricuspidalisinsufficiëntie bij HFrEF: RV-PA-ontkoppeling en sMR

INTRODUCTION: Heart failure with reduced ejection fraction (HFREF) accompanied by moderate or severe ventricular tricuspid-valve leaflet regurgitation (vTR2/3) is prognostically unfavourable, however, the underlying pathophysiology has not yet been sufficiently clarified. The hypothesis of a causative role of left ventricular (LV) dysfunction +/- secondary mitral regurgitation (sMR) on extent and severity of secondary vTR was investigated. METHODS: We integrated right ventricular (RV) pressure-volume loop and Swan-Ganz catheter data with RV/LV imaging findings in retrospective analysis of 134 HFREF patients. RESULTS: Parameters independently associated with the presence of vTR2/3 were (i) presence of sMR (adjusted odds-ratio: adOR=1.67, p=0.045), (ii) increased pulmonary vascular pulsatile RV loads (lower PA compliance, adOR=0.43, p=0.021; AUC=0.82, cut-off:<2.24 ml/mmHg, p<0.001), mainly due to concomitant moderate/severe sMR (sMR2/3) (adOR=4.56, p=0.012), and (iii) progressive un-coupling of RV elastance/contractility (Ees) to an increasing total afterload (pulmonary elastance, Ea) (Ees/Ea ratio: adOR=0.024, p=0.005; AUC=0.84, cut-off:<0.6, p<0.001). In addition, the RV-pulmonary artery (PA) un-coupling was not only determined by the higher afterload in vTR2/3, but was also observed across the entire total afterload range (Ea tertile). This resulted in a larger and more dysfunctional RV in vTR2/3 compared to vTR0/1, independent of the afterload. RV-PA un-coupling and reduced PA-compliance were independently associated with all-cause mortality. DISCUSSION: The vTR2/3 in context of HFREF was independently associated with the presence of sMR, increased pulsatile loads, and a pronounced RV-PA un-coupling over almost entire afterload range. Future studies will need to determine under which haemodynamic conditions a mechanical TR reduction in HFREF patients is advisable.