Clinical Applications of Pressure-Volume Assessment in Congenital Heart Disease

Central Illustration. Summary of the various clinical applications of pressure-volume loop analysis in congenital heart disease. TPVR, Transcatheter pulmonary valve replacement.

Figure 1. Theoretical considerations for PV loops analysis and interpretation. Examples of RV and LV PV loops superimposed on each other. (A) AoP, aortic systolic pressure; sPAP, systolic pulmonary artery pressure; LV, left ventricle; RV, right ventricle; SV, stroke volume; (B, C) Ea, effective arterial elastance; EDPVR, end-diastolic pressure-volume relationship; Ees, end-systolic elastance; ESPVR, end-systolic pressure-volume relationship; (D) PE, potential energy; SW, stroke work; PVA, Pressure-volume area.

Figure 2. Infrastructure needed for invasive PV loop assessment. CD Leycom’s Inca PV Loop System (A, C) CD Leycom high-fidelity conductance catheter with tip electrodes and pressure sensor (B). Conduct NT software and monitor (D). PV, pressure-volume.

Figure 3. Preload modification by vena caval occlusion helps determine the end-systolic and end-diastolic relationships by linear regression. EDV and SV decrease from loop 1 to loop 4 in this theoretical example of RV PV loops. EDPVR, end-diastolic pressure–volume relationship; ESPVR, end-systolic pressure–volume relationship; Ves, end-systolic volume; Pes, end-systolic pressure. EDV, end-diastolic volume; PV, pressure-volume; RV, right ventricle; SV, stroke volume.

Figure 4. PV relationship of the morphologically RV in systemic position (blue), and of the morphologically LV in pulmonary position (green) in a patient with L-loop transposition of great arteries using conductance catheters. The systemic RV has a prominent isovolumic contraction and relaxation phases and more closely resembles typical LV loops. LV, left ventricle; PV, pressure-volume; RV, right ventricle.

Figure 5. Representative PV loops in a pediatric patient with coarctation of the aorta before and after transcatheter stent angioplasty obtained using conductance catheter positioned in the LV apex. Blue loops: Pre-stenting, Green: After stenting. Arterial elastance (Ea) decreased from 1.72 to 1.59 (8%) and VA coupling improved by 5%. Ees, end-systolic elastance; PV, pressure-volume; VA, ventricular-arterial.

Figure 6. Representative PV loops obtained using a conductance catheter in a patient with congenitally corrected transposition of great arteries status post double switch operation during CRT. Settings are described based on which ventricle was paced first followed by the ventriculo-ventricular delay. Purple: LV only. Blue: RV only. Turquoise: LV-RV 0 msec. Red: LV-RV 40 msec. Green: RV-LV 40 msec. LV-RV 40 msec provided the highest LV stroke work. Compared to this setting, RV only pacing led to a 30% decline in LV stroke work. CRT, cardiac resynchronization therapy; LV, left ventricle; PV, pressure-volume; RV, right ventricle.