Introduction
Methods
Population Study
CMR Protocol
Four-Dimensional Flow Magnetic Resonance Imaging Analysis and Blood Flow Energetics
Statistical Analysis
Results
Patients Characteristics
n = 55 | |
---|---|
Age at the study (years) | 21.9 ± 10 |
Male gender n (%) | 36 (65.5%) |
Weight (kg) n = 55 | 54.2 ± 18 |
Height (cm) n = 55 | 159.9 ± 17.9 |
Body surface area (m2) | 1.5 ± 0.3 |
Diagnosis | |
Tricuspid atresia | 7 (13%) |
Double inlet left ventricle | 7 (13%) |
Complex 2 ventricles | 11 (20%) |
Hypoplastic left heart syndrome | 6 (11%) |
Complex Atrio-Ventricular canal | 14 (25%) |
PAIVS | 6 (11%) |
Ebstein anomaly | 1 (1.8%) |
Mitral atresia | 3 (5.4%) |
Ventricle type | |
Two ventricles | 8 (14.5%) |
Left ventricle | 26 (47%) |
Right ventricle | 20 (36%) |
Indetermined ventricle | 1 (1.8) |
Shunt n (%) | 27 (54%) |
Glenn n (%) | 48 (87.3%) |
Age at Fontan (months) | 5.4 (3.8, 7.1) |
Follow-up from Fontan (years) | 14 ± 9 |
Type Fontan | |
Extracardiac conduit | 46 (83.7%) |
Intracardiac conduit | 2 (3.6%) |
Lateral tunnel | 7 (12.7%) |
Fenestrated (%) | 17 (31.5%) |
Peripheral O2 sat (%) | 94 (92, 96) |
PLE n (%) | 4 (7.4%) |
Arrhythmia n (%) | 9 (17.6%) |
Heart failuren (%) | 11 (20.4%) |
Nt Pro BNP | 113 (54, 219) |
Significant TR n (%) | 22 (44%) |
Diuretic therapyn (%) | 17 (34%) |
Antiarrhythmic therapy n (%) | 10 (20.4%) |
Peak VO2 (ml/kg/min) | 20 ± 4.9 |
Predicted peak VO2 (%) | 48.5 ± 10.2 |
HR reserve (bpm) | 58.4 ± 27.3 |
O2 pulse (ml/min) | 9.1 ± 5.6 |
VE/VCO2 slope | 37.9 ± 8.3 |
VO2 work slope | 9.9 ± 1.5 |
FEV1 (l/min) | 3 ± 0.9 |
FEV 1 (%) | 77 ± 19 |
FEV1/VC (%) | 94 ± 11 |
TL (% of predicted) | 79 ± 13.5 |
Peak VE (l/min) | 50 (38.5, 64) |
Basal VD/VT | 0.22 ± 0.16 |
Peak VD/VT | 0.16 ± 0.03 |
DLCO sbHB | 52.4 ± 13.4 |
DLCO/VA | 71 ± 23 |
MVV (l/min) | 123 ± 28 (117; 42, 64) |
BRR (l) | 70 ± 28 |
CMR Data
Population study | |
---|---|
CMR | |
End diastolic ventricular volume (ml/m2) | 102 (83, 125) |
End systolic ventricular volume (ml/m2) | 48 (33, 66) |
Ventricular ejection fraction (%) | 53±10.7 |
Ventricular mass (g/m2) | 68.5±19.2 |
Ventricular mass/volume ratio | 0.6 (0.5, 0.7) |
SVC flow (l/min/m2) | 0.9 (0.7, 1.2) |
AOPC flow (l/min/m2) | 0.9 (0.6, 1.5) |
Conduit/tunnel IVC-Pas flow (l/min/m2) | 1.3 ± 0.5 |
Cardiac index (ll/min/m2) | 3 ± 0.7 |
LPA flow (l/min/m2) | 1 ± 0.4 |
RPA flow (l/min/m2) | 1.2 ± 0.5 |
Left PVs flow (l/min/m2) | 1.2 (1, 1.6) |
Right PVs flow (l/min/m2) | 1.5 ± 0.4 |
LPA axial diameter (mm) | 13 ± 3.7 |
LPA latero-lateral diameter (mm) | 13.6 ± 3.9 |
LPA stenosis, N (%) | 10 (18.2%) |
RPA axial diameter (mm) | 14.7 ± 4.1 |
RPA latero-lateral diameter (mm) | 15.6 ± 4.4 |
RPA stenosis, N (%) | 7 (12.7%) |
RSVC_RPA streamlines (%) | 62.51 ± 35.37 |
RSVC_LPA streamlines (%) | 38.4 ± 35.31 |
Conduit/tunnel IVC/Pas_RPA streamlines (%) | 47.05 ± 40.50 |
Conduit/tunnel IVC/Pas_LPA streamlines (%) | 52.29 ± 40.65 |
Mean conduit/tunnel IVC/Pas Vel (cm/s) | 31.4 (20.5, 39.7) |
Mean conduit/tunnel IVC/Pas Flow jet angle | 13.7 (9.9, 23.9) |
Mean eccentricity flow conduit/tunnel IVC/Pas | 0.05 (0.04, 0.08) |
Caval Flow Distribution
Adverse Cardiac Outcome
HF group (N: 8) | No HF group (N: 47) | p | |
---|---|---|---|
Age at the study (years) | 26 ± 18 | 21 ± 8 | 0.2 |
Body surface area (m2) | 1.52 ± 0.4 | 1.55 ± 0.332 | 0.8 |
Age at Fontan (years) | 5.8 (5.3;9.4) | 5.3 (3.8;7) | 0.543 |
RPA axial diameter (mm) | 11.3 ± 3.5 | 15.3 ± 4 | 0.001 |
RPA latero-lateral (mm) | 13.1 ± 4.2 | 16 ± 4 | 0.08 |
RPA stenosis, N (%) | 3 (37.5) | 4 (8.5) | 0.02 |
LPA axial diameter (mm) | 13.5 ± 5.9 | 12.9 ± 3.2 | 0.706 |
LPA latero-lateral diameter (mm) | 14 ± 5.37 | 13.54 ± 3.64 | 0.762 |
LPA stenosis, N (%) | 2 (25) | 8 (17) | 0.6 |
Conduit/tunnel IVC/Pas flow (l/min/m2) | 0.75 ± 0.55 | 1.36 ± 0.55 | 0.003 |
SVC flow (l/min/m2) | 1.27 ± 0.61 | 0. 99 ± 0.37 | 0.087 |
CI 4D (l/min/m2) | 3.43 ± 0.90 | 2.97 ± 0.67 | 0.102 |
LPA flow (l/min/m2) | 0.94 ± 0.45 | 0.98 ± 0.38 | 0.743 |
RPA flow (l/min/m2) | 0.96 ± 0.36 | 1.25 ± 0.48 | 0.111 |
AOPC flow (l/min/m2) | 1.7 ± 1.47 | 0.95 ± 0.68 | 0.030 |
End diastolic ventricular volume (ml/m2) | 137 ± 56 | 105 ± 32 | 0.026 |
End systolic ventricular volume (ml/m2) | 77.5 ± 54.2 | 51.5 ± 25 | 0.031 |
Ventricular ejection fraction (%) | 47.6 ± 14.7 | 54 ± 9.7 | 0.124 |
Ventricular mass (g/m2) | 77.5 ± 28 | 66 ± 17 | 0.1 |
Ventricular mass/volume ratio | 0.58 ± 0.12 | 0.64 ± 0.16 | 0.3 |
Peripheral O2 sat (%) | 85.8 ± 10.4 | 94 ± 3.1 | < 0.001 |
Ln Nt ProBNP | 5.6 ± 0.87 | 4.48 ± 1.183 | 0.037 |
Conduit/tunnel IVC/Pas flow jet Angle | 39.2 ± 22.8 | 15.2 ± 8.9 | < 0.001 |
Conduit/tunnel IVC/Pas Vel (cm/s) | 25.4 ± 11 | 35.2 ± 17.2 | 0.1 |
Mean eccentricity IVC/Pas flow | 0.1 ± 0.04 | 0.06 ± 0.02 | 0.002 |
Segmental 4D-Flow CMR Energetics Parameters
Discussion
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The flow distribution of the SVC was preferential to the RPA while the flow distribution of IVC Conduit/tunnel-PA was quite symmetric with a slightly higher distribution to the LPA.
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Patients with HF have lower blood flow of IVC Conduit/tunnel-PA and higher mean sectional jet angle and vorticity in comparison with the remaining population.
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Higher EL/KE index was associated with reduced functional aerobic capacity evaluated by peakVO2/kg/min and impaired lung function, expressed as reduced ventilatory response (peak VE and MVV) with increased of the dead space ventilation (VD/VT) at physical exercise.