Clinical potential of hemodynamic ramp test by simultaneous echocardiography and right heart catheterization for aortic insufficiency in a patient with continuous-flow left ventricular assist device

Aortic insufficiency (AI) is an important adverse event in patients with continuous-flow (CF) left ventricular assist device (LVAD) support. AI is often progressive, resulting in elevated 2-year morbidity and mortality. The effectiveness of echocardiographic ramp studies in patients with AI has been unclear. Here, we describe a patient with a CF-LVAD implant who underwent aortic valve replacement (AVR), following assessment of AI using a hemodynamic ramp test with simultaneous echocardiography and right heart catheterization (RHC). The patient was a 21-year-old man with cardiogenic shock due to acute myocarditis, who underwent HeartWare CF-LVAD (HVAD) implantation. Heart failure persisted despite increased doses of diuretics and inotrope, as well as an increased HVAD pump rate. HVAD monitoring revealed a correlation between increased HVAD pump rate and flow at each speed step. A hemodynamic ramp test with simultaneous transthoracic echocardiography and RHC revealed a significant discrepancy between HVAD pump flow and cardiac output (CO) at each speed step; moreover, pulmonary capillary wedge pressure remained high. Therefore, the patient underwent AVR. Subsequently, his low CO symptoms disappeared and inotropes were successfully discontinued. A postoperative hemodynamic ramp test revealed that AVR had successfully closed the loop of blood flow and reduced the discrepancy between HVAD pump flow and CO, thereby increasing CO. The patient was then discharged uneventfully. In conclusion, a hemodynamic ramp test with simultaneous echocardiography and RHC was useful for the evaluation of the causal relationship between AI and low CO, and for selection of surgical treatment for AI in a patient with CF-LVAD.