Quantitative assessment of cardiac output and left ventricular function by noninvasive phase‐contrast and cine MRI: Validation study with invasive pressure‐volume loop analysis in a swine model

Abstract

Purpose: To validate noninvasive cardiac output measurements of phase-contrast magnetic resonance imaging (PC-MRI) and cine MRI using an invasive pressure-volume (PV) loop technique on a swine model. Materials and Methods:We compared three methods for evaluating cardiac function at rest and under pharmaceutical low-dose inotropic infusion conditions: 1) phasecontrast MRI, 2) cine MRI, and 3) PV loop relationship. These measurements were made in 14 domestic pigs under rest conditions. Identical MRI acquisitions and PV loop analysis were performed on six pigs from the same group that received an infusion of dobutamine 2.5 mg/ kg/min. Cardiac outputs from all measurements were analyzed and compared using linear regression and BlandAltman analysis.Results: Noninvasive PC-MRI and cine MRI did not show any significant differences compared to an invasive PV loop technique for measurement of cardiac output under both rest (PC-MRI, cine MRI, and PV loop, 3.17 6 0.45, 3.18 6 0.61, 3.45 6 0.41 L/min, respectively) and pharmaceutical low-dose inotropic infusion conditions (PC-MRI, cine MRI, and PV loop, 4.78 6 0.53, 4.7 6 0.6, 4.96 6 0.48 L/min, respectively). Statistical analysis showed good agreement of cardiac output measurements at rest (R 2 ¼ 0.83) and under low-dose inotropic infusion conditions (R 2 ¼ 0.74) using PC-MRI and PV loop techniques. Cardiac output measurement using cine MRI and PV loop techniques also showed good agreement at rest (R 2 ¼ 0.85) and under low-dose inotropic infusion conditions (R 2 ¼ 0.76). Furthermore, cardiac outputs determined with the three modalities showed good agreement over a wide range of heart rates (90-180 bpm).Conclusion: MRI can provide a reliable, noninvasive measurement of cardiac output that can be carried out without the complications that are inherent with current invasive procedures.

A feasible method for non-invasive measurement of pulmonary vascular resistance in pulmonary arterial hypertension: Combined use of transthoracic Doppler-echocardiography and cardiac magnetic resonance. Non-invasive estimation of pulmonary vascular resistance

“…CMR can overcome the limitations of TTE and provides the best non-invasive method for measurements of SV and CO. Previous reports have showed that CMR-derived CO had good accuracy and reproducibility compared with RHC-derived CO [24], [25], [26]. In this study, our findings also showed the reasonable agreement between CMR and RHC, and further corroborated the previous studies.…”

“…Since PVR is directly related to trans-pulmonary pressure gradient (MPAP–PCWP) and inversely related to CO, the non-invasive PVR can be achieved by non-invasive estimation of (MPAP–PCWP) and CO, respectively. It has been previously demonstrated that TTE estimated MPAP and PCWP reliably, but its ability to calculate CO was not as accurate and reproductive as CMR [25], [26]. In this study, our findings also proved the flaw of 2D-TTE in the measurement of CO. On the contrary, CMR was the best non-invasive modality to measure CO but its ability to determine MPAP/PCWP was limited [13], [32].…”

“…TTE had the potential to estimate mean pulmonary arterial pressure (MPAP) and pulmonary capillary wedge pressure (PCWP) reliably [14], [15], [16], [17], [18], [19], [20], [21], [22], [23]. In the non-invasive measurement of cardiac output (CO), however, CMR had more accuracy and reproducibility than TTE [24], [25], [26]. Based on the formula (MPAP–PCWP)/CO, it became possible to calculate PVR directly with TTE-derived (MPAP–PCWP) and CMR-derived CO.…”

Admittance‐based pressure–volume loop measurements in a porcine model of chronic myocardial infarction

“…Indeed, studies on agreement and correlation between different imaging techniques (e.g. MRI, echocardiography) and volumes measured by PV methods in both small‐ and large‐animal models are inconsistent (Amirhamzeh et al 1996; Feldman et al 2000; Jacoby et al 2006; Nielsen et al 2007; Winter et al 2008; Porterfield et al 2009; Lin et al 2011). It should be noted, however, that 3DE moderately underestimates absolute LV volumes in comparison to MRI (Dorosz et al 2012; Greupner et al 2012), which could partly explain the overestimation by the AS of both EDV and ESV at follow‐up.…”

Society for Cardiovascular Magnetic Resonance (SCMR) expert consensus for CMR imaging endpoints in clinical research: part I - analytical validation and clinical qualification

“… LV mass: excellent validation against gold-standard in animals and excised human hearts after transplantation (Additional file 1 : Table 3ai.1). LV function/cardiac output: limited validation against invasive conductance catheters [ 8 , 9 ] …”