Korean J Radiol.  2018 Dec;19(6):1042-1052. 10.3348/kjr.2018.19.6.1042.

Computed Tomography-Based Ventricular Volumes and Morphometric Parameters for Deciding the Treatment Strategy in Children with a Hypoplastic Left Ventricle: Preliminary Results

• Goo HW
• Park SH

• KMID: 2424844
• DOI: http://doi.org/10.3348/kjr.2018.19.6.1042

Abstract

OBJECTIVE
To determine the utility of computed tomography (CT) ventricular volumes and morphometric parameters for deciding the treatment strategy in children with a hypoplastic left ventricle (LV).
MATERIALS AND METHODS
Ninety-four consecutive children were included in this study and divided into small LV single ventricle repair (SVR) (n = 28), small LV biventricular repair (BVR) (n = 6), disease-matched control (n = 19), and control (n = 41) groups. The CT-based indexed LV volumes, LV-to-right-ventricular (LV/RV) volume ratio, left-to-right atrioventricular valve (AVV) area ratio, left-to-right AVV diameter ratio, and LV/RV long dimension ratio were compared between groups. Proportions of preferred SVR in the small LV SVR group suggested by the parameters were evaluated.
RESULTS
Indexed LV end-systolic (ES) and end-diastolic (ED) volumes in the small LV SVR group (6.3 ± 4.0 mL/m² and 14.4 ± 10.2 mL/m², respectively) were significantly smaller than those in the disease-matched control group (16.0 ± 4.7 mL/m² and 37.7 ± 12.0 mL/m², respectively; p < 0.001) and the control group (16.0 ± 5.5 mL/m² and 46.3 ± 10.8 mL/m², respectively; p < 0.001). These volumes were 8.3 ± 2.4 mL/m² and 21.4 ± 5.3 mL/m², respectively, in the small LV BVR group. ES and ED indexed LV volumes of < 7 mL/m² and < 17 mL/m², LV/RV volume ratios of < 0.22 and < 0.25, AVV area ratios of < 0.33 and < 0.24, and AVV diameter ratios of < 0.52 and < 0.46, respectively, enabled the differentiation of a subset of patients in the small LV SVR group from those in the two control groups. One patient in the small LV biventricular group died after BVR, indicating that this patient might not have been a good candidate based on the suggested cut-off values.
CONCLUSION
CT-based ventricular volumes and morphometric parameters can suggest cut-off values for SVR in children with a hypoplastic LV.

Keyword

Cardiac CT; Hypoplastic left ventricle; Child; Ventricular volume quantification; Biventricular repair; Single ventricle repair; Threshold-based segmentation

MeSH Terms

Child*
Heart Ventricles*
Humans

Figure

• 

  Fig. 1 Cardiac CT imaging in 27-day-old boy with repaired complete transposition of great arteries with ventricular septal defect and coarctation of aorta.A. Four-chamber CT image obtained at ED phase showing segmented left ventricular cavity in pink. B. Oblique frontal volume-rendered CT image revealing left ventricular EDV (8.5 mL) highlighted in light pink. C. Four-chamber CT image obtained at ED phase illustrating segmented right ventricular cavity in pink. D. Oblique frontal volume-rendered CT image displaying right ventricular EDV (10.6 mL) highlighted in light pink. E. Short-axis CT image acquired at ED phase showing MV area (light blue dotted line) and TV area (pink dotted line) necessary for calculation of atrioventricular valve area ratio. F. Four-chamber CT image obtained at ED phase illustrating MV and TV diameters (solid arrows) as well as left ventricular and right ventricular long dimensions (dotted arrows). CT = computed tomography, ED = end-diastolic, EDV = end-diastolic volume, LA = left atrium, LV = left ventricle, MV = mitral valve, RA = right atrium, RV = right ventricle, TV = tricuspid valve

• 

  Fig. 2 Scatter plots illustrating relationships among various combinations of ESVs and morphometric data.A. Scatter plot demonstrating that indexed left ventricular ESV < 7.0 mL/m2 (dotted line) and LV/RV ESV ratio < 0.22 (dotted line) can differentiate 16 of 28 patients (57.1%) in small LV SVR group from patients in two control groups. B. Scatter plot showing that indexed left ventricular ESV < 7.0 mL/m2 (dotted line) and ES atrioventricular area ratio < 0.33 (dotted line) can differentiate 17 of 28 patients (60.7%) in small LV SVR group from patients in two control groups. C. Scatter plot demonstrating that indexed left ventricular ESV < 7.0 mL/m2 (dotted line) and ES atrioventricular diameter ratio < 0.52 (dotted line) can differentiate 14 of 28 patients (50.0%) in small LV SVR group from patients in two control groups. D. Scatter plot demonstrating that LV/RV ESV ratio < 0.22 (dotted line) and ES atrioventricular diameter ratio < 0.52 (dotted line) can be used to differentiate 18 of 28 patients (64.3%) in small LV SVR group from patients in two control groups. AVV = atrioventricular valve, Control-1 = disease matched control group, Control-2 = control group, ES = end-systolic, ESV = end-systolic volume, ESVi = indexed end-systolic volume, LV/RV = LV-to-right-ventricular, SVR = single ventricle repair

• 

  Fig. 3 Scatter plots illustrating various combinations of EDVs and morphometric data.A. Scatter plot demonstrating that indexed left ventricular EDV < 17.0 mL/m2 (dotted line) and LV/RV EDV ratio < 0.25 (dotted line) can differentiate 17 of 28 patients (60.7%) in small LV SVR group from patients in two control groups. B. Scatter plot showing that indexed left ventricular EDV < 17.0 mL/m2 (dotted line) and ED atrioventricular area ratio < 0.24 (dotted line) can differentiate 16 of 28 patients (57.1%) in small LV SVR group from patients in two control groups. C. Scatter plot demonstrating that indexed left ventricular EDV < 17.0 mL/m2 (dotted line) and ED atrioventricular diameter ratio < 0.46 (dotted line) can differentiate 17 of 28 patients (60.7%) in small LV SVR group from patients in two control groups. D. Scatter plot demonstrating that LV/RV EDV ratio < 0.25 (dotted line) and ED atrioventricular diameter ratio < 0.24 (dotted line) can be used to differentiate 19 of 28 patients (67.9%) in small LV SVR group from patients in two control groups. EDVi = indexed end-diastolic volume

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