Table 2 3D printed model construction and key characteristics

Schmauss et al., 2012 [39]

Cardiac CT

Aortic root, aortic arch and the ascending aorta

Polyjet

N/A

N/A

N/A

N/A

Ripley et al., 2016 [32]

ECG gated Cardiac CT, images at peak systole

Aortic root and LVOT. Valve leaflets not included

SLA

Clear flexible photosensitive resin

5 h

N/A

Agreement of minimum and maximum annulus diameter measurements between 3D model and patient's imaging data

Fujita et al., 2016 [43]

CT

Ascending aorta, aortic valve, prosthetic mitral valve and LVOT

SLA

Photosensitive resin

N/A

N/A

N/A

Qian et al., 2017 [37]

Contrast-enhanced CT, images taken at systolic phase

Aortic root, aortic annulus, LVOT and

valve leaflets

Polyjet

Photopolymers:

Stiff sinusoidal fibres—VeroBlackPlus® (RGD875)

Elastic matrix—TangoPlus® (FullCure 930)

Segmentation of anatomical structures: 5–10 min

Formation of digital files for printing: 5 min

9–10 h to print ten 3D models

Post-printing processing time: 45 min

Cost of printing materials per model: $150 to $200

Model imitates, to some degree, the strain-stiffening characteristic

of human soft tissue

Model submerged in water at 37 °C to mimic temperature of body, ensured full expansion of the valve

Hosny et al., 2018 [36]

ECG gated cardiac CTA, images taken at diastolic phase

Aortic root, annulus, LVOT, valve leaflets with calcifications

Polyjet

Photopolymers:

Calcified leaflets and valve sizer printed with rigid white VeroWhitePlus (RGD835), aortic root/ non-calcified leaflets printed with flexible transparent TangoPlus® (FLX930)

N/A

N/A

Agreement in annulus diameter measurements between 3D model and patient's imaging data

Mechanical properties of human tissue were approximated but, strain-stiffening behaviour of human aortic tissue not replicated

Tanaka et al., 2018 [33]

ECG gated multi-detector CT, images taken at end-diastole

aortic annulus with valve leaflets, aortic root, LVOT, thoracic and abdominal aorta, iliofemoral arteries

SLA—for all structures except aortic annulus

Printed material not specified. Aortic annulus with three leaflets constructed using silicone moulding

N/A

N/A

Elasticity of calcified regions and mechanical stiffness of aortic annulus were adjusted to those of human tissue

Pulsatile flow circulation system replicated HR and mAP of patients

Yaku et al., 2018 [42]

CT

N/A

SLA

Photosensitive resin:

Aortic wall printed with Polyurethane resin. Intramural haematoma was made using epoxy resin (hard material)

N/A

N/A

Pressure gauge measure pressure exerted onto aortic wall

Hatoum et al., 2019 [40]

Cardiac CT, image taken at diastole

LVOT, aortic annulus with valve leaflets, aortic root and ascending aorta

Polyjet

Photopolymers:

Calcified leaflets printed with rigid white VeroWhitePlus (RGD835), soft tissues printed with flexible transparent TangoPlus® (FLX930)

N/A

N/A

Model connected to pulse duplicator left heart simulator that replicated mAP and HR

Zhang et al., 2019 [38]

ECG gated cardiac CTA, images at systolic phase

Aortic root, valve leaflets with calcifications and LVOT

N/A

HeartPrint® Flex for non-calcified regions: transparent, flexible, mimicking modulus of elasticity of human arterial tissue

Material for hard calcifications—N/A

N/A

N/A

Calcifications printed with a different coloured material to allow visualisation

Haghiashtiani et al., 2020 [41]

Cardiac CT

Aortic wall, aortic annulus, valve leaflets with calcifications, LVOT

Custom-built 3D printing system (AGS1000, Aerotech)

Silicone sealant and silicone grease mixed at various specified weight ratios to print (a) Myocardium and leaflets and (b) aortic wall. Speckling material for calcifications on vales. Colouring agent marked the intermediate implantation depth

3D models left in ambient air for 5 to 7 days after printing, to complete curing

N/A

Young's modulus of meta-materials fall within the range of moduli values for human tissue. Materials failed to represent strain-stiffening behaviour of human tissue at high strains

Reiff et al., 2020 [35]

ECG gated CT, images at systolic phase

LVOT, aortic root and ascending aorta

Native leaflets not included

FDM

Thermoplastic polyurethane (Ninjaflex flexible)

N/A

N/A

Model approximates the modulus of elasticity of the human aorta

Thorburn et al., 2020 [34]

ECG gated cardiac CT

Aortic root, the coronary artery ostia and LVOT

Native leaflets not included

FDM

Thermoplastic polyurethane (Ninjaflex flexible)

Sealant material

Printing time alone: 4 h / model

N/A

Closed pressure system. Saline to represent blood. Radiopaque marker on the annulus to allow them to replicate implantation depth as in vivo

Redondo et al., 2021 [44]

ECG gated cardiac CT

Thoracic aorta, aortic arch, descending aorta, aortic root and coronary ostia

SLA

Photosensitive resin with flexible silicone-like characteristics

N/A

N/A

N/A