Left atrial appendage occlusion simulation based on three-dimensional printing: new insights into outcome and technique

Development and validation of 3-dimensional simulators for penile prosthesis surgery

BACKGROUND

The acquisition of skills in penile prosthesis surgery has many limitations mainly due to the absence of simulators and models for training. Three-dimensional (3D) printed models can be utilized for surgical simulations, as they provide an opportunity to practice before entering the operating room and provide better understanding of the surgical approach.

AIM

This study aimed to evaluate and validate a 3D model of human male genitalia for penile prosthesis surgery.

METHODS

This study included 3 evaluation and validation stages. The first stage involved verification of the 3D prototype model for anatomic landmarks compared with a cadaveric pelvis. The second stage involved validation of the improved model for anatomic accuracy and teaching purposes with the Rochester evaluation score. The third stage comprised validation of the suitability of the 3D prototype model as a surgical simulator and for skill acquisition. The third stage was performed at 3 centers using a modified version of a pre-existing, validated questionnaire and correlated with the Rochester evaluation score.

OUTCOME

We sought to determine the suitability of 3D model for training in penile prosthesis surgery in comparison with the available cadaveric model.

RESULTS

The evaluation revealed a high Pearson correlation coefficient (0.86) between questions of the Rochester evaluation score and modified validated questionnaire. The 3D model scored 4.33 ± 0.57 (on a Likert scale from 1 to 5) regarding replication of the relevant human anatomy for the penile prosthesis surgery procedure. The 3D model scored 4.33 ± 0.57 (on a Likert scale from 1 to 5) regarding its ability to improve technical skills, teach and practice the procedure, and assess a surgeon's ability. Furthermore, the experts stated that compared with the cadaver, the 3D model presented greater ethical suitability, reduced costs, and easier accessibility.

CLINICAL IMPLICATIONS

A validated 3D model is a suitable alternative for penile prosthesis surgery training.

STRENGTHS AND LIMITATIONS

This is the first validated 3D hydrogel model for penile prosthesis surgery teaching and training that experts consider suitable for skill acquisition. Because specific validated guidelines and questionnaires for the validation and verifications of 3D simulators for penile surgery are not available, a modified questionnaire was used.

CONCLUSION

The current 3D model for penile prosthesis surgery shows promising results regarding anatomic properties and suitability to train surgeons to perform penile implant surgery. The possibility of having an ethical, easy-to-use model with lower costs and limited consequences for the environment is encouraging for further development of the models.

An Exploratory Pilot Study on the Application of Radiofrequency Ablation for Atrial Fibrillation Guided by Computed Tomography-Based 3D Printing Technology

Radiofrequency ablation (RFA) is the treatment of choice for atrial fibrillation (AF). Additionally, the utilization of 3D printing for cardiac models offers an in-depth insight into cardiac anatomy and cardiovascular diseases. The study aims to evaluate the clinical utility and outcomes of RFA following in vitro visualization of the left atrium (LA) and pulmonary vein (PV) structures via 3D printing (3DP). Between November 2017 and April 2021, patients who underwent RFA at the First Affiliated Hospital of Xinxiang Medical University were consecutively enrolled and randomly allocated into two groups: the 3DP group and the control group, in a 1:1 ratio. Computed tomography angiography (CTA) was employed to capture the morphology and diameter of the LA and PV, which facilitated the construction of a 3D entity model. Additionally, surgical procedures were simulated using the 3D model. Parameters such as the duration of the procedure, complications, and rates of RFA recurrence were meticulously documented. Statistical analysis was performed using the t-test or Mann-Whitney U test to evaluate the differences between the groups, with a P-value of less than 0.05 considered statistically significant. In this study, a total of 122 patients were included, with 53 allocated to the 3DP group and 69 to the control group. The analysis of the morphological measurements of the LA and PV taken from the workstation or direct entity measurement showed no significant difference between the two groups (P > 0.05). However, patients in the 3DP group experienced significantly shorter RFA times (97.03 ± 28.39 compared to 120.51 ± 44.76 min, t = 3.05, P = 0.003), reduced duration of radiation exposure (2.55 [interquartile range 2.01, 3.24] versus 3.20 [2.28, 3.91] min, Z = 3.23, P < 0.001), and shorter modeling times (7.68 ± 1.03 compared to 8.89 ± 1.45 min, t = 5.38, P < 0.001). 3DP technology has the potential to enhance standard RFA practices by reducing the time required for intraoperative interventions and exposure to radiation.

Preprocedural Planning of Left Atrial Appendage Occlusion: A Review of the Use of Additive Manufacturing

Stroke is a significant public health problem, with non-valvular atrial fibrillation (NVAF) being one of its main causes. This cardiovascular arrhythmia predisposes to the production of intracardiac thrombi, mostly formed in the left atrial appendage (LAA). When there are contraindications to treatment with oral anticoagulants, another therapeutic option to reduce the possibility of thrombus formation in the LAA is the implantation of an occlusion device by cardiac catheterization. The effectiveness of LAA occlusion is dependent on accurate preprocedural device sizing and proper device positioning at the LAA ostium, to ensure sufficient device anchoring and avoid peri-device leaks. Additive manufacturing, commonly known as three-dimensional printing (3DP), of LAA models is beginning to emerge in the scientific literature to address these challenges through procedural simulation. This review aims at clarifying the impact of 3DP on preprocedural planning of LAA occlusion, specifically in the training of cardiac surgeons and in the assessment of the perfect adjustment between the LAA and the biomedical implant.

A systematic review of the use of 3D printing in left atrial appendage occlusion procedures

The placement of a left atrial appendage occlusion (LAAO) device can be a technically challenging transcatheter-based procedure. Key challenges include accurate pre-procedural device sizing and proper device positioning at the LAA ostium to ensure sufficient device anchoring and avoid peri-device leaks. To address these challenges, 3D printing (3DP) of LAA models has recently emerged in the literature, first being described in 2015. We present a review of the benefits and drawbacks of employing this technology for LAAO procedures. Pre-procedurally the use of 3DP can consistently and accurately determine LAAO device size over standard of care approaches. Intra-procedurally 3DP's impact entailed a statistically significant decrease in the number of devices used per procedure, as well as in the fluoroscopic time and dose. Post-procedurally, there is some evidence that 3DP could reduce the rate of peri-device leaks, with limited data on its effect on complication rates. Based on existing evidence, we recommend the focused application of 3DP to cases of complex LAA anatomy and for the training of proceduralists. Lastly, we address the emergence of next generation LAAO devices and AR/VR systems that could limit even this narrow window of clinical benefit afforded by 3DP. This article is protected by copyright. All rights reserved.

3D-Printing to Plan Complex Transcatheter Paravalvular Leaks Closure

Background: Percutaneous closure of paravalvular leak (PVL) has emerged as an alternative to surgical management in selected cases. Achieving complete PVL occlusion, while respecting prosthesis function remains challenging. A multimodal imaging analysis of PVL morphology before and during the procedure is mandatory to select an appropriate device. We aim to explore the additional value of 3D printing in predicting device related adverse events including mechanical valve leaflet blockade, risk of device embolization and residual shunting. Methods: From the FFPP registries (NCT05089136 and NCT05117359), we included 11 transcatheter PVL closure procedures from three centers for which 3D printed models were produced. Cardiac CT was used for segmentation for 3D printed models (3D-heartmodeling, Caissargues, France). Technology used a laser to fuse very fine powders (TPU Thermoplastic polyurethane) into a final part-laser sintering technology (SLS) with an adapted elasticity. A simulation on 3D printed model was performed using a set of occluders. Results: PVLs were located around aortic prostheses in six cases, mitral prostheses in four cases and tricuspid ring in one case. The device chosen during the simulation on the 3D printed model matched the one implanted in eight cases. In the three other cases, a similar device type was chosen during the procedures but with a different size. A risk of prosthesis leaflet blockade was identified on 3D printed models in four cases. During the procedure, the occluder was removed before release in one case. In another case the device was successfully repositioned and released. In two patients, leaflet impingement was observed post-operatively and surgical device removal had to be performed. Conclusion: In a case-series of complex transcatheter PVL closure procedures, hands-on simulation testing on 3D printed models proved its usefulness to plan and facilitate these challenging procedures.

Complex transcatheter left atrial appendage closure using a tailored trans-jugular approach simulated by 3D printing: a case report

Background

Transcatheter left atrial appendage (LAA) closure (LAAc) is less feasible in patients with unusual LAA anatomy.

Case summary

A 65-year-old woman with persistent atrial fibrillation was referred for LAAc. Transesophageal echocardiography (TEE) revealed spontaneous contrast in the LAA without formation of a thrombus; the LAA shape was tortuous and difficult to assess. A first LAAc procedure was unsuccessful given the unsuitable sheath position. Therefore, a soft three-dimensional (3D) model printing was performed by laser sintering and revealed excessive sheath kinking with an inferior approach, but successful deployment would be feasible using a superior approach. Successful trans-jugular implantation of a Watchman FLX 31 device in stable position without residual leakage was achieved during the subsequent procedure. At 3-month follow-up, and after cessation of oral anticoagulation, the patient’s symptoms improved. Imaging demonstrated complete LAA occlusion and correct placement of the device along the LAA superior axis.

Discussion

This is the first-reported clinical case of a complex transcatheter LAAc through a trans-jugular approach. Simulating the patient’s anatomy with a laser sintering 3D-printed model showed why the transfemoral approach failed, validated the trans-jugular procedure, enabled selection of the simple curve access sheath that had the most direct trajectory towards the LAA, confirmed that transseptal puncture was possible, allowed determination of the angle of puncture, enabled selection of the most appropriate LAA device and had a very low cost compared with planning software or other printing methods.

Construction and Evaluation of Small-Diameter Bioartificial Arteries Based on a Combined-Mold Technology

Arterial stenosis or blockage is the leading cause of cardiovascular disease, and the common solution is to substitute the arteries by autologous veins or bypass the blood vessels physically. With the development of science and technology, arteries with diameter larger than 6 mm can be substituted by unbiodegradable polymers, such as polytetrafluoroethylene, clinically. Nevertheless, the construction of a small-diameter (less than 6 mm) artery with living cells has always been a thorny problem. In this study, a suit of combined mold was designed and forged for constructing small-diameter arterial vessels. Based on this combined mold, bioactive arterial vessels containing adipose-derived stem cells (ASCs) and different growth factors (GFs) were assembled together to mimic the inner and middle layers of the natural arteries. Before assembling, ASCs and GFs were loaded into a gelatin/alginate hydrogel. To enhance the mechanical property of the bilayer arterial vessels, polylactic–glycolic acid (PLGA) was applied on the surface of the bilayer vessels to form the outer third layer. The biocompatibility, morphology and mechanical property of the constructed triple-layer arterial vessels were characterized. The morphological results manifested that cells grow well in the gelatin/alginate hydrogels, and ASCs were differentiated into endothelial cells (ECs) and smooth muscle cells (SMCs), respectively. In addition, under the action of shear stress produced by the flow of the culture medium, cells in the hydrogels with high density were connected to each other, similar to the natural vascular endothelial tissues (i.e., endothelia). Especially, the mechanical property of the triple-layer arterial vessels can well meet the anti-stress requirements as human blood vessels. In a word, a small-diameter arterial vessel was successfully constructed through the combined mold and has a promising application prospect as a clinical small-diameter vessel graft.

Imaging-Based, Patient-Specific Three-Dimensional Printing to Plan, Train, and Guide Cardiovascular Interventions: A Systematic Review and Meta-Analysis

BACKGROUND

To tailor cardiovascular interventions, the use of three-dimensional (3D), patient-specific phantoms (3DPSP) encompasses patient education, training, simulation, procedure planning, and outcome-prediction.

AIM

This systematic review and meta-analysis aims to investigate the current and future perspective of 3D printing for cardiovascular interventions.

METHODS

We systematically screened articles on Medline and EMBASE reporting the prospective use of 3DPSP in cardiovascular interventions by using combined search terms. Studies that compared intervention time depending on 3DPSP utilisation were included into a meta-analysis.

RESULTS

We identified 107 studies that prospectively investigated a total of 814 3DPSP in cardiovascular interventions. Most common settings were congenital heart disease (CHD) (38 articles, 6 comparative studies), left atrial appendage (LAA) occlusion (11 articles, 5 comparative, 1 randomised controlled trial [RCT]), and aortic disease (10 articles). All authors described 3DPSP as helpful in assessing complex anatomic conditions, whereas poor tissue mimicry and the non-consideration of physiological properties were cited as limitations. Compared to controls, meta-analysis of six studies showed a significant reduction of intervention time in LAA occlusion (n=3 studies), and surgery due to CHD (n=3) if 3DPSPs were used (Cohen's d=0.54; 95% confidence interval, 0.13 to 0.95; p=0.001), however heterogeneity across studies should be taken into account.

CONCLUSIONS

3DPSP are helpful to plan, train, and guide interventions in patients with complex cardiovascular anatomy. Benefits for patients include reduced intervention time with the potential for lower radiation exposure and shorter mechanical ventilation times. More evidence and RCTs including clinical endpoints are needed to warrant adoption of 3DPSP into routine clinical practice.

3D printing for left atrial appendage closure: A meta-analysis and systematic review

BACKGROUND

Three-dimensional printing (3D) has emerged as an alternative to imaging to guide left atrial appendage closure (LAAC) device sizing.

AIMS

We assessed the usefulness of 3D printing compared to a standard imaging-only approach for LAAC.

METHODS

We identified studies comparing an imaging-only with a 3D printing approach in LAAC. A fixed-effects meta-analysis was performed targeting a co-primary endpoint of disagreement in device sizing and leaks.

RESULTS

Eight studies that assigned 283 participants to an imaging-only approach and 3D printing approach (145 patients) were included. 3D printing significantly reduced the risk of the co-primary endpoint (risk raio (RR) = 0.19; 95% confidence interval (CI) 0.09-0.37), with consistency across the studies (I2 = 0%). Individually, both device size disagreements [RR 0.13 (95% CI 0.06-0.29), P < 0.001] and leaks [RR 0.24 (95% CI 0.09-0.64) P = 0.004] were reduced under a 3D printing modeling strategy.

CONCLUSION

Compared with an imaging-only strategy, 3D printing is associated with reduction in device size disagreements and leaks.

Improving Left Atrial Appendage Occlusion Device Size Determination by Three-Dimensional Printing-Based Preprocedural Simulation

Background

The two-dimensional (2D)-based left atrial appendage (LAA) occluder (LAAO) size determination by using transesophageal echocardiography (TEE) is limited by the structural complexity and wide anatomical variation of the LAA.

Objective

This study aimed to assess the accuracy of the LAAO size determination by implantation simulation by using a three-dimensional (3D)-printed model compared with the conventional method based on TEE.

Methods

We retrospectively reviewed patients with anatomically and physiologically properly implanted the Amplatzer Cardiac Plug and Amulet LAAO devices between January 2014 and December 2018 by using the final size of the implanted devices as a standard for size prediction accuracy. The use of 3D-printed model simulations in device sizing was compared with the conventional TEE-based method.

Results

A total of 28 cases with the percutaneous LAA occlusion were reviewed. There was a minimal difference [−0.11 mm; 95% CI (−0.93, 0.72 mm); P = 0.359] between CT-based reconstructed 3D images and 3D-printed left atrium (LA) models. Device size prediction based on TEE measurements showed poor agreement (32.1%), with a mean difference of 2.3 ± 3.2 mm [95% CI (−4.4, 9.0)]. The LAAO sizing by implantation simulation with 3D-printed models showed excellent correlation with the actually implanted LAAO size (r = 0.927; bias = 0.7 ± 2.5). The agreement between the 3D-printed and the implanted size was 67.9%, with a mean difference of 0.6 mm [95% CI (−1.9, 3.2)].

Conclusion

The use of 3D-printed LA models in the LAAO size determination showed improvement in comparison with conventional 2D TEE method.

Computed Tomography-Derived Three-Dimensional Printed Models versus Two-Dimensional Transesophageal Echocardiography for Left Atrial Appendage Occlusion Device Planning: A Systematic Review and Meta-Analysis

Objective

This systematic review and meta-analysis compared computed tomography (CT)-derived three-dimensional (3D) modeling versus two-dimensional transesophageal echocardiography (TEE) for left atrial appendage occluder (LAAO) device planning.

Background

LAAO device planning is commonly performed with TEE. However, procedures often require multiple devices and deployments due to inaccurate sizing from TEE. The use of CT three-dimensional (3D) models for LAAO device planning may improve accuracy.

Methods

Four clinical studies that reported procedural and clinical outcomes for CT-derived 3D modeling versus TEE for LAAO device planning were identified. End points were accurate device sizing, procedure failure, number of devices used per procedure, fluoroscopy time, and post-procedure leak. Risk ratio (RR) and mean difference (MD) with a 95% confidence interval (CI) were calculated by the Mantel-Haenszel and inverse variance methods.

Results

A total of 166 participants were included. When compared with conventional imaging, the use of 3D printed models was associated with less fluoroscopy time (MD -6.98 minutes, 95% CI -12.68 to -1.28, p=0.02) and lower risk of occluder device peri-prosthetic leak (RR 0.23, 95% CI 0.07-0.73, p=0.01) for LAAO. There were signals towards lower number of devices per procedure (MD -0.56 devices, 95% CI -1.16-0.05, p=0.07) and less total procedure time (MD -13.50 minutes, 95% CI -28.14-1.14, p=0.07) with printed modeling for LAAO. There was no difference between modalities in rates of procedure failure.

Conclusions

CT-derived 3D printed models for LAAO device planning may offer the advantages of lower LAAO device peri-prosthetic leak and less fluoroscopy time when compared with conventional TEE guidance.

Clinical Impact of Preprocedural CT-Based 3D Computational Simulation of Left Atrial Appendage Occlusion with Amulet

Aims

Standard of care (SoC) device size selection with transoesophageal echocardiography (TOE) and computed tomography (CT) in LAAO can be challenging due to a certain degree of variability at both patient and device levels. The aim of this study was to prospectively evaluate the clinical impact of 3D computational modelling software in the decision-making of left atrial appendage occlusion (LAAO) with Amplatzer Amulet.

Methods and Results

SoC preprocedural assessments as well as CT-based 3D computational simulations (FEops) were performed in 15 consecutive patients scheduled for LAAO with Amulet. Preprocedural device size selection and degree of confidence were determined after SoC and after FEops-based assessments and compared to the implanted device. FEops-based preprocedural assessment correctly selected the implanted device size in 11 out of 15 patients (73.3%), compared to 7 patients (46.7%) for SoC-based assessment. In 4 patients (26.7%), FEops induced a change in device size initially selected by SoC. In the 7 patients (46.7%) in which FEops confirmed the SoC device size selection, the degree of confidence of the size selection increased from 6.4 ± 1.4 for SoC to 8.1 ± 0.7 for FEops. One patient (6.7%) could not be implanted for anatomical reason, as correctly identified by FEops.

Conclusions

Preprocedural 3D computational simulation by FEops impacts Amulet size selection in LAAO compared to TOE and CT-based SoC assessment. Operators could consider FEops computational simulation in their preprocedural device size selection.

Three-dimensional printing for heart diseases: clinical application review

Heart diseases remain the top threat to human health, and the treatment of heart diseases changes with each passing day. Convincing evidence shows that three-dimensional (3D) printing allows for a more precise understanding of the complex anatomy associated with various heart diseases. In addition, 3D-printed models of cardiac diseases may serve as effective educational tools and for hands-on simulation of surgical interventions. We introduce examples of the clinical applications of different types of 3D printing based on specific cases and clinical application scenarios of 3D printing in treating heart diseases. We also discuss the limitations and clinically unmet needs of 3D printing in this context.

Value of FEops HEARTguide patient-specific computational simulations in the planning of left atrial appendage closure with the Amplatzer Amulet closure device: rationale and design of the PREDICT-LAA study

BACKGROUND

Optimal preprocedural planning is essential to ensure successful device closure of the left atrial appendage (LAA).

DESIGN

The PREDICT-LAA study is a prospective, international, multicentre, randomised controlled trial (ClinicalTrials.gov NCT04180605). Two hundred patients eligible for LAA closure with an Amplatzer Amulet device (Abbott, USA) will be enrolled in the study. Patients will be allocated to a computational simulation arm (experimental) or standard treatment arm (control) using a 1:1 randomisation. For patients randomised to the computational simulation arm, preprocedural planning will be based on the analysis of cardiac computed tomography (CCT)-based patient-specific computational simulations (FEops HEARTguide, Ghent, Belgium) in order to predict optimal device size and position. For patients in the control arm, preprocedural planning will be based on local practice including CCT analysis. The LAA closure procedure and postprocedural antithrombotic therapy will follow local practice in both arms. The primary endpoint of the study is incomplete LAA closure and device-related thrombus as assessed at 3 months postprocedural CCT. Secondary endpoints encompass procedural efficiency (number of devices used, number of repositioning, procedural time, radiation exposure, contrast dye), procedure-related complications within 7 days postprocedure and a composite of all-cause death and thromboembolic events at 12 months.

CONCLUSION

The objective of the PREDICT-LAA study is to test the hypothesis that a preprocedural planning for LAA closure with the Amplatzer Amulet device based on patient-specific computational simulations can result in a more efficient procedure, optimised procedural outcomes and better clinical outcomes as compared with a standard preprocedural planning.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Registry (NCT04180605).

Clinical situations for which 3D printing is considered an appropriate representation or extension of data contained in a medical imaging examination: adult cardiac conditions

BACKGROUND

Medical 3D printing as a component of care for adults with cardiovascular diseases has expanded dramatically. A writing group composed of the Radiological Society of North America (RSNA) Special Interest Group on 3D Printing (SIG) provides appropriateness criteria for adult cardiac 3D printing indications.

METHODS

A structured literature search was conducted to identify all relevant articles using 3D printing technology associated with a number of adult cardiac indications, physiologic, and pathologic processes. Each study was vetted by the authors and graded according to published guidelines.

RESULTS

Evidence-based appropriateness guidelines are provided for the following areas in adult cardiac care; cardiac fundamentals, perioperative and intraoperative care, coronary disease and ischemic heart disease, complications of myocardial infarction, valve disease, cardiac arrhythmias, cardiac neoplasm, cardiac transplant and mechanical circulatory support, heart failure, preventative cardiology, cardiac and pericardial disease and cardiac trauma.

CONCLUSIONS

Adoption of common clinical standards regarding appropriate use, information and material management, and quality control are needed to ensure the greatest possible clinical benefit from 3D printing. This consensus guideline document, created by the members of the RSNA 3D printing Special Interest Group, will provide a reference for clinical standards of 3D printing for adult cardiac indications.

The value of the left atrial appendage orifice perimeter of 3D model based on 3D TEE data in the choice of device size of LAmbre™ occluder

Preoperative optimal selection of the occluder size is crucial in percutaneous left atrial appendage (LAA) occlusion, and the maximal width of the LAA orifice is the main reference index, however it can not fully meet the practical operation requirements. We retrospectively analyzed three-dimensional (3D) transesophageal echocardiography (TEE) and computed tomography (CT) imaging dataset of the 41 patients who underwent LAA occlusion with LAmbre™ system. The LAA orifice parameters were overall evaluated to determine their role in device size selection. Eight LAA 3D models of the four cases who had been replaced their device during the procedure based on TEE and CT were printed out to verify the optimal parameter decision strategy. There was a significant concordance of the results between 3D TEE and CT in the LAA orifice evaluation. The correlations between the perimeter and maximal width measurements by 3D TEE and the closure disk of the device were stronger than that between the area measurements and the closure disk (r = 0.93, 0.95, 0.86, respectively and p < 0.001 all), and the result was similar to that by CT (r = 0.92, 0.93, 0.84, respectively and p < 0.001 all). The ratios of the maximal width to the minimal width of the four cases were all > 1.4, however the rest 37 cases were all ≤ 1.4. Based on the comprehensive assessment of the LAA orifice perimeter and maximal width of the 3D printed models, the experiments were all succeed just for one try. The LAA orifice perimeter of 3D printed model based on 3D TEE may help in choosing the optimal device size of LAmbre™, especially for the LAA with flater ostial shape.

Cardiovascular Three-Dimensional Printing in Non-Congenital Percutaneous Interventions

Three-dimensional (3D) printing technology is emerging as a potential new tool for the planning of medical interventions. In the last few years, increasing data have accumulated on its ability to guide interventional cardiology procedures, going beyond initial reports in congenital heart disease settings. In fact, there is compelling evidence on the advantages of a 3D-printed guided strategy for left atrial appendage closure, suggesting a high success rate with optimal device selection and lower radiation load. Furthermore, there is emerging experience in aortic root printing, which may improve the success rate and safety of transcatheter aortic valve replacement and may be of particular interest for targeting low-risk populations. Additionally, there are stimulating reports in mitral valve intervention, setting the tone for this new field in cardiovascular percutaneous intervention. In this clinically oriented paper, we will review current 3D printing use in interventional cardiology and we will address future directions, with a focus on procedural planning and medical simulation.

Methods for verification of 3D printed anatomic model accuracy using cardiac models as an example

Background

Medical 3D printing has brought the manufacturing world closer to the patient’s bedside than ever before. This requires hospitals and their personnel to update their quality assurance program to more appropriately accommodate the 3D printing fabrication process and the challenges that come along with it.

Results

In this paper, we explored different methods for verifying the accuracy of a 3D printed anatomical model. Methods included physical measurements, digital photographic measurements, surface scanning, photogrammetry, and computed tomography (CT) scans. The details of each verification method, as well as their benefits and challenges, are discussed.

Conclusion

There are multiple methods for model verification, each with benefits and drawbacks. The choice of which method to adopt into a quality assurance program is multifactorial and will depend on the type of 3D printed models being created, the training of personnel, and what resources are available within a 3D printed laboratory.

Peridevice Leak After Left Atrial Appendage Closure: Incidence, Risk Factors, and Clinical Impact

BACKGROUND

Limited studies reported the rate and clinical impact of peridevice leaks (PDL) after percutaneous left atrial appendage closure (LAAC).

METHODS

All consecutive patients with a nonvalvular atrial fibrillation admitted for LAAC between November 2011 and October 2016 were prospectively enrolled. The follow-up included clinical, transesophageal echocardiography, and/or cardiac computed tomography angiogram (CCTA). PDL was defined by the presence of contrast within the left atrial appendage on CCTA, and Major Adverse Cardiac Event (MACE) included stroke, device-related thrombosis, and cardiovascular death.

RESULTS

Overall, 77 patients (mean CHA₂DS₂-VASc score = 4.4 ± 1.5 and mean HAS-BLED = 3.4 ± 1.1) were implanted using Amplatzer Cardiac Plug (n = 24), Amulet (n = 37), or Watchman devices (n = 16). Indications were stroke recurrence despite adequate oral anticoagulation (OAC, n = 6) or contraindication to long-term OAC (n = 71). From 3-month to 12-month CCTA follow-up, the PDL rate decreased from 68.5% to 56.7% (P = 0.02), without any difference between the various devices. Patients with PDL were more often in permanent atrial fibrillation, and had a larger landing zone diameter, a lower ratio of device compression, and a more frequent off-axis position of the device. A device compression ratio < 10% was the only parameter associated with PDL occurrence. During follow-up (median 236 days) the MACE rate was 9.1%, with no statistically significant difference between patients with vs without PDL (12% vs 4.3%, P = 0.3).

CONCLUSIONS

The PDL rate detected by CCTA after LAAC was high, especially in cases with a low device compression ratio (< 10%), but decreased over time. The incidence of MACE was quantitatively greater with PDL, but the difference was not statistically significant. Larger studies are needed to determine the clinical importance of PDL.

Three-dimensional printing models in congenital heart disease education for medical students: a controlled comparative study

BACKGROUND

This study sought to assess, using subjective (self-assessment) and objective (MCQ) methods, the efficacy of using heart models with ventricular septal defect lesions produced with three-dimensional printing technology in a congenital heart disease curriculum for medical students.

METHODS

Three computed tomography datasets of three subtypes of ventricular septal defects (perimembranous, subarterial and muscular, one for each) were obtained and processed for building into and printing out 3D models. Then a total of 63 medical students in one class were randomly allocated to two groups (32 students in the experimental, and 31 the control). The two groups participated in a seminar with or without a 3D heart model, respectively. Assessment of this curriculum was carried out using Likert-type questionnaires as well as an objective multiple choice question test assessing both knowledge acquisition, and structural conceptualization. Open-ended questions were also provided for getting advice and suggestion on 3D model utilization in CHD education.

RESULTS

With these 3D models, feedback shown in the questionnaires from students in experimental group was significantly more positive than their classmates in the control. And the test results also showed a significant difference in structural conceptualization in favor of the experimental group.

CONCLUSION

It is effective to use heart models created using current 3D printing technology for congenital heart disease education. It stimulates students' interest in congenital heart disease and improves the outcomes of medical education.