Hemodynamic Response to Device Titration in the Shunted Single Ventricle Circulation: A Patient Cohort Modeling Study

Area of Science:

• Cardiovascular Physiology
• Medical Device Engineering
• Pediatric Cardiology

Background:

• Clinical outcomes for patients with a single ventricle and a systemic-to-pulmonary shunt receiving ventricular assist device (VAD) support are often suboptimal.
• Challenges in optimizing VAD support and balancing pulmonary and systemic circulations contribute to these poorer outcomes.

Purpose of the Study:

• To investigate the hemodynamic response to VAD support in a shunted single ventricle circulation.
• To understand the impact of VAD flow titration on systemic and pulmonary hemodynamics in this patient population.

Main Methods:

• Utilized a lumped-parameter network model to simulate six patient-specific clinical cases with a systemic-to-pulmonary shunt.
• Incorporated patient hemodynamic data and simulated increasing VAD flow rates (5 to 10 L/min/m²).

Main Results:

• Pulmonary arterial pressure remained stable in 5 out of 6 cases as VAD flow increased; it rose in one case.
• An average VAD flow of 6.5 ± 1.2 L/min/m² was required to achieve a 30% arterial-venous O2 saturation difference, higher than in non-shunted scenarios.
• Significant variability in hemodynamic responses to VAD support was observed across individual patient cases.

Conclusions:

• Hemodynamic modeling can aid in tailoring perioperative VAD management for shunted single ventricle patients.
• Individualized VAD management strategies are crucial, and modeling may identify patients most likely to benefit from VAD support.