Abstract 4290: Percutaneous Tricuspid Valve Replacement - Experimental Results
Objective: Tricuspid regurgitation (TR) reduces cardiac output and increases central venous pressure with secondary organ dysfunction. The open surgical approach is the only option to treat TR and is associated with a mortality up to 22%. We report the first experience of interventional treatment of tricuspid regurgitation by percutaneous implantation of valved stents into the inferior (IVC) and superior vena cava (SVC) to replace tricuspid valve function in a modell of acute TR.
Methods: Acute TR grade III-IV was created in nine sheep (54 –75kg) by chordae and leaflet avulsion using a 0.07-inch retrograde wire blade. TR was confirmed by angiography and by a prominent ventricular pulse wave in central venous pressure recording. Two self-expanding nitinol stents containing a porcine pulmonary valve were then implanted in the IVC and SVC in a transcatheter approach under fluoroscopy. Implantation was performed through the right jugular vein by means of a 21F catheter. Hemodynamics were continuously monitored, valve function was verified by angiography and echocardiography.
Results: Tricuspid regurgitation grade III-IV was successfully created in nine animals and resulted in a reduction of cardiac output (CO) from 5.15±1.69l/min to 2.9±1.16l/min. A ventricular wave in the right atrium and inferior vena cava of 16.2±2.33mmHg and 16.2±2.82mmHg was observed. After valve deployment, the ventricular wave in the IVC significantly decreased to 13.9±2.97mmHg and cardiac output significantly increased to 4.20±0.84l/min. At autopsy, correct device position was verified in all successfully implanted animals. No macroscopic damage or thrombus formation was observed.
Conclusion: In high-grade TR, percutaneous implantation of valved stents in central venous position reduces venous regurgitation and increases cardiac output in the acute experiment. Implantation of one or two valves in central venous position is technically feasable and partially replaces tricuspid valve function. Chronic studies are currently performed to evaluate this concept with longer follow-up. This technique of heterotopic trucuspid valve implantation could expand the therapeutic options in the future for patients with relevant TR but high risk for open heart surgery.