Kinetic energy efficiency of single ventricle and TCPC using 4D flow MRI

Background: Extreme preterm birth conveys an elevated risk of heart failure by young adulthood. Smaller biventricular chamber size, diastolic dysfunction, and pulmonary hypertension may contribute to reduced ventricular-vascular coupling. However, how hemodynamic manipulations may affect right ventricular (RV) function and coupling remains unknown. Methods: As a pilot study, 4D flow MRI was used to assess the effect of afterload reduction and heart rate reduction on cardiac hemodynamics and function. Young adults born premature were administered sildenafil (a pulmonary vasodilator) and metoprolol (a beta blocker) on separate days, and MRI with 4D flow completed before and after each drug administration. Endpoints include cardiac index (CI), direct flow fractions, and ventricular kinetic energy including E/A wave kinetic energy ratio. Results: Sildenafil resulted in a median CI increase of 0.24 L/min/m2 (P=0.02), mediated through both an increase in heart rate (HR) and stroke volume. Although RV ejection fraction improved only modestly, there was a significant increase (4% of end diastolic volume) in RV direct flow fraction (P=0.04), consistent with hemodynamic improvement. Metoprolol administration resulted in a 5-bpm median decrease in HR (P=0.01), a 0.37 L/min/m2 median decrease in CI (P=0.04), and a reduction in time-averaged kinetic energy (KE) in both ventricles (P<0.01), despite increased RV diastolic E/A KE ratio (P=0.04). Conclusions: Despite reduced right atrial workload, metoprolol significantly depressed overall cardiac systolic function. Sildenafil, however, increased CI and improved RV function, as quantified by the direct flow fraction. The preterm heart appears dependent on HR, but sensitive to RV afterload manipulations.

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Scan–rescan reproducibility of diastolic left ventricular kinetic energy, viscous energy loss and vorticity assessment using 4D flow MRI: analysis in healthy subjects

The International Journal of Cardiovascular Imaging ◽

10.1007/s10554-017-1291-z ◽

2018 ◽

Vol 34 (6) ◽

pp. 905-920 ◽

Cited By ~ 6

Author(s):

Vivian P. Kamphuis ◽

Jos J. M. Westenberg ◽

Roel L. F. van der Palen ◽

Pieter J. van den Boogaard ◽

Rob J. van der Geest ◽

...

Keyword(s):

Kinetic Energy ◽

Energy Loss ◽

Healthy Subjects ◽

Left Ventricular ◽

4D Flow Mri ◽

4D Flow ◽

Flow Mri

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Unilateral branch pulmonary artery stenting in tetralogy of fallot improves ventricular function

European Heart Journal - Cardiovascular Imaging ◽

10.1093/ehjci/jeab090.066 ◽

2021 ◽

Vol 22 (Supplement_2) ◽

Author(s):

MM Bissell ◽

L Mills ◽

DGW Cave ◽

R Foley ◽

JP Greenwood ◽

...

Keyword(s):

Kinetic Energy ◽

Ejection Fraction ◽

Pulmonary Artery ◽

Longitudinal Strain ◽

Left Ventricular ◽

Energy Curve ◽

4D Flow Mri ◽

4D Flow ◽

Flow Mri

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): NIHR Background Pulmonary artery stenosis (PAS) occurs commonly in patients with tetralogy of fallot (ToF). Cardiac function and especially left ventricular longitudinal strain has been identified as an important prognostic factor for long term survival in ToF. The clinical relevance of unilateral PAS to long-term bi-ventricular function is poorly understood. Purpose We sought to evaluate the effect of resolving unilateral pulmonary artery obstruction on right and left ventricular performance. Methods We prospectively included 40 patients with TOF between 2016 and 2020, 20 who underwent unilateral PAS stenting and as comparison 20 who underwent surgical pulmonary valve replacement (PVR). MRI data was acquired during routine clinical care before and around 6-12 months after the procedure. 4 PAS patients attended additional research scans acquiring ventricular 4D flow MRI data. 4D flow MRI data was compared to the average kinetic energy curve of 10 age-matched healthy volunteers. Results Of the 20 patients undergoing PAS, 2 also underwent percutaneous PVR and were excluded from the comparison analysis. All patients in the PAs group showed an improvement in branch PA flow differential post procedure. Patients undergoing PAS were younger than those undergoing PVR (median 12 vs 19 years, p < 0.001). Other baseline anatomical and functional parameters including right ventricular (RV) volume indexed to body surface are (RVEDV/BSA) were comparable (pre PAS median 151 [122,170] vs pre PVR 162 [140,191]; p = 0.217). While in the PVR group the right ventricular volumes reduced in both end-diastole and end-systole, in the PAS group RV function improved due to reduced end-systolic volume with largely stable end-diastolic volumes. Changes in the left ventricle (LV) were even more interesting. In the PVR group ejection fraction improved due to an increase in end-diastolic volume with no improvement in ventricular longitudinal strain. In contrast, in the PAS group LV ejection fraction improved by a reduction in end-systolic volume and the PAS group showed a small but significant improvement in LV longitudinal strain. In addition, ¾ patients undergoing 4D flow MRI assessment showed LV kinetic energy curve more similar to the healthy volunteer averaged LV kinetic energy curve after PAS. The 4th patient already had a near normal LV kinetic energy curve prior to PAS. Conclusion Unilateral PAS does not alter RV end-diastolic volumes but improves RV function. LV ejection fraction improvement is similar to that seen after PVR, but importantly PAS also improved LV longitudinal strain. This suggests that PAS might positively influence long term morbidity and mortality risk in ToF patients, but a larger multi-centre long term follow-up study is needed to confirm this.

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Right ventricular kinetic energy: 4D flow MRI analysis of healthy volunteers and repaired Tetralogy of Fallot

Journal of Cardiovascular Magnetic Resonance ◽

10.1186/1532-429x-16-s1-o46 ◽

2014 ◽

Vol 16 (S1) ◽

Cited By ~ 1

Author(s):

Daniel Jeong ◽

Alejandro Roldán-Alzate ◽

Christopher J Francois

Keyword(s):

Kinetic Energy ◽

Right Ventricular ◽

Healthy Volunteers ◽

Tetralogy Of Fallot ◽

4D Flow Mri ◽

4D Flow ◽

Repaired Tetralogy Of Fallot ◽

Flow Mri

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Hemodynamic interplay of vorticity, viscous energy loss, and kinetic energy from 4D Flow MRI and link to cardiac function in healthy subjects and Fontan patients

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00806.2020 ◽

2021 ◽

Vol 320 (4) ◽

pp. H1687-H1698

Author(s):

Vivian P. Kamphuis ◽

Arno A. W. Roest ◽

Pieter J. van den Boogaard ◽

Lucia J. M. Kroft ◽

Hildo J. Lamb ◽

...

Keyword(s):

Kinetic Energy ◽

Energy Loss ◽

Cardiovascular Magnetic Resonance Imaging ◽

Healthy Subjects ◽

Energy Levels ◽

Resonance Imaging ◽

4D Flow Mri ◽

4D Flow ◽

Flow Mri ◽

Fontan Patients

Physiologic intraventricular hemodynamic interplay/coupling is present in the healthy left ventricle between vorticity versus viscous energy loss and kinetic energy from four-dimensional flow cardiovascular magnetic resonance imaging (4D Flow MRI). Conversely, Fontan patients present compensatory pathophysiologic hemodynamic coupling by an increase in intraventricular vorticity that positively correlates to viscous energy loss and kinetic energy levels in the presence of maintained normal stroke volume. Altered vorticity and energetics are found in the presence of normal ejection fraction in Fontan patients.

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In vivo quantification of blood mixing in single ventricle patients with Fontan circulation using 4D flow MRI

Journal of Cardiovascular Magnetic Resonance ◽

10.1186/1532-429x-15-s1-e88 ◽

2013 ◽

Vol 15 (S1) ◽

Author(s):

Kelly B Jarvis ◽

Susanne Schnell ◽

Maya Gabbour ◽

Alex J Barker ◽

Ramona Lorenz ◽

...

Keyword(s):

Single Ventricle ◽

Fontan Circulation ◽

4D Flow Mri ◽

4D Flow ◽

Flow Mri

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P889Clinical significance of four-dimensional flow magnetic resonance imaging measurement of turbulent kinetic energy for hypertrophic obstructive cardiomyopathy

European Heart Journal ◽

10.1093/eurheartj/ehz747.0486 ◽

2019 ◽

Vol 40 (Supplement_1) ◽

Author(s):

J Matsuda ◽

H Takano ◽

T Sekine ◽

H Sangen ◽

Y Kubota ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Kinetic Energy ◽

Turbulent Kinetic Energy ◽

Hypertrophic Obstructive Cardiomyopathy ◽

Resonance Imaging ◽

4D Flow Mri ◽

4D Flow ◽

Flow Mri ◽

Echocardiographic Findings

Abstract Four-dimensional flow magnetic resonance imaging (4D flow MRI) provides the detailed visualization of complex blood flow patterns and the evaluation of energy loss. Turbulent kinetic energy estimation (TKE) is reported to have good correlation with irreversible pressure loss in patients having aortic stenosis or great vessel disease. However, little is known about the usefulness of 4D flow MRI and the significance of TKE value in hypertrophic cardiomyopathy (HCM). Purpose The aims of this study were to investigate the relationship between TKE value and echocardiographic findings, clinical symptoms and evaluate the usefulness of 4D flow MRI to distinguish hypertrophic obstructive cardiomyopathy (HOCM) from non-obstructive HCM (HNCM). Methods From April 2018 to January 2019, 18 hypertrophic obstructive cardiomyopathy (HOCM) and 14 non-obstructive HCM (HNCM) patients underwent 4D flow MRI. We investigated TKE value calculated by 4D flow MRI, echocardiographic findings; left ventricular pressure gradient (LVPG), mitral regurgitation (MR) and clinical symptom. Results HOCM was defined by the 30 mmHg or greater of LVPG (HOCM: 87.7±47.3 mmHg, HNCM; 5.8±7.8 mmHg, p<0.001). TKE value in HOCM patients was significantly higher than HNCM (14.2±4.7 mJ vs. 9.0±4.6 mJ, p<0.001). There was a significant positive linear relationship between TKE value and LVPG (r=0.488, p=0.046). There was no significant relationship between NYHA functional class and TKE value (p=0.47) or LVPG (p=0.11). ROC curve analysis showed that optimal cut off point of TKE value between HOCM and HNCM (sensitivity=95%, specificity=62%, AUC=0.798) was 9.270 mJ. Multiple linear regression showed that there was significant association between severity of MR and combination of TKE (p=0.015) or LVPG (p–=0.012). A representative case demonstrated the significant reduction of TKE value 1 week and 3 months after alcohol septal reduction compared with that obtained before the procedure (Figure) Conclusion Our findings suggest that 4D Flow MRI can effectively evaluate the energy dissipation associated with LV outflow tract obstruction and TKE value is useful for identifying HOCM. TKE value also can be the novel parameter of the severity of HOCM.

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