Dual Admittance Catheter‐Derived Biventricular Pressure‐Volume Analysis in Swine: Comparison with Contrast‐Enhanced Computed Tomography During Transient Pressure Overload
Authors: Konecny Filip , Smith Cody , Techiryan George , Canty John M , Weil Brian R 
Published: June 2021

ObjectiveAdmittance catheter‐derived pressure‐volume (PV) analysis offers the ability to assess dynamic changes in ventricular performance. The present study was designed to evaluate the feasibility and accuracy of biventricular PV analysis by comparing admittance catheter‐derived measurements of left (LV) and right ventricular (RV) volumes with data obtained from simultaneous contrast‐enhanced cardiac computed tomography (CT) before, during, and after transient pressure overload in swine.\MethodsClosed‐chest propofol‐anesthetized swine (n=5) were instrumented with admittance catheters in the LV and RV for continuous biventricular PV analysis (ADV500; Transonic SciSense, Inc.). Multi‐detector CT with iodinated contrast (1 mL/kg at 4 mL/s) was performed before, during, and 30‐minutes after transient pressure overload elicited by a 1‐hour intravenous infusion of phenylephrine (PE; 18 mg/hour). Right and left ventricular end‐diastolic volume, end‐systolic volume, and stroke volume were calculated simultaneously with each modality.ResultsPE elicited a significant rise in LV pressure (110±6/4±1 to 208±9/25±3 mmHg; p<0.01) and RV pressure (25±2/3±1 to 44±2/8±2 mmHg; p<0.05) that normalized 30‐minutes after the end of the infusion period (LV: 99±8/8±2 mmHg; RV: 25±2/3±1 mmHg). Biventricular PV analysis demonstrated a significant increase in LV and RV end‐diastolic volume and end‐systolic volume during PE that normalized in the RV, but not LV, 30‐minutes after cessation of PE (Table). These changes were confirmed by contrast‐enhanced cardiac CT‐derived measurement of ventricular volumes, with no significant differences between PV and CT at any timepoint. Persistent LV dilatation after PE was accompanied by a reduction in LV contractility (LV dP/dtmax: 1288±110 mmHg/sec vs. 2023±89 mmHg/sec at baseline, p<0.05) that reflected stretch‐induced stunning following a ~6‐fold rise in LV end‐diastolic pressure during PE. This was not observed in the RV, as RV contractility was preserved following PE (from 369±42 mmHg/sec at baseline to 352±26 mmHg/sec after PE; p=0.77).ConclusionsBiventricular PV analysis is feasible in swine and provides reasonably accurate measurements of ventricular volumes compared with contrast‐enhanced cardiac CT. Employing this approach during transient PE infusion demonstrated persistent chamber dilatation and systolic dysfunction in the LV, but not RV, consistent with stretch‐induced stunning caused by an acute elevation in preload.Support or Funding InformationThe National Heart Lung and Blood Institute (HL‐061610), the American Heart Association (17SDG33660200), the National Center for Advancing Translational Sciences (UL1TR001412), the Department of Veterans Affairs (1IO1BX002659), and the Albert and Elizabeth Rekate Fund in Cardiovascular Medicine.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.