Transcatheter Mitral Valve Repair Simulator Equipped with Eye Tracking Based Performance Assessment Capabilities: A Pilot Study.

BACKGROUND: The increase in cardiovascular disease cases that require minimally invasive treatment is inducing a new need to train physicians to perform them safely and effectively. Nevertheless, adaptation to simulation-based training has been slow, especially for complex procedures. OBJECTIVES: We describe a newly developed mitral valve repair (MVR) simulator, equipped with new objective performance assessment methods, with an emphasis on its use for training the MitraClip™ procedure. METHODS: The MVR contains phantoms of all anatomical structures encountered during mitral valve repair with a transvenous, transseptal approach. In addition, several cameras, line lasers, and ultraviolet lights are used to mimic echocardiographic and fluoroscopic imaging and with a remote eye tracker the cognitive behaviour of the operator is recorded. A pilot study with a total of 9 interventional cardiologists, cardiac surgeons and technical experts was conducted. All participants performed the MitraClip procedure on the MVR simulator using standard interventional tools. Subsequently, each participant completed a structured questionnaire to assess the simulator. RESULTS: The simulator functioned well, and the implemented objective performance assessment methods worked reliably. Key performance metrics such as x-ray usage were comparable with results from studies assessing these metrics in real interventions. Fluoroscopy imaging is realistic for the transseptal puncture but reaches its limits during the final steps of the procedure. CONCLUSION: The functionality and objective performance assessment of the MVR simulator were demonstrated. Especially for complex procedures such as the MitraClip procedure, this simulator offers a suitable platform for risk-free training and education.

Tangled wire in a Dacron band during Cardioband transcatheter tricuspid annuloplasty-How to solve the problem.

Transcatheter tricuspid valve intervention (TTVI) is an emerging treatment for patients with symptomatic severe tricuspid regurgitation (TR). Currently, the issues that arise during TTVI are unclear. Here, a 78-year-old woman with severe TR underwent transcatheter tricuspid valve annuloplasty using a Cardioband (Edwards Lifesciences, Irvine, CA). We attempted to cinch the Dacron band after anchoring; however, it was impossible to connect the distal tip of the size adjustment tool and the Dacron band because the cinching wire was tangled around the Dacron band. We resolved this issue without surgical intervention, and eventually cinched the annulus. Final echocardiography revealed dramatic TR reduction. To our knowledge, no study has reported a tangled wire in a Dacron band during Cardioband use. Clinicians should be aware of the risks accompanying this concern in case where it is impossible to connect the distal tip of the size adjustment tool and the Dacron band during cinching.

Quantification of Avoidable Radiation Exposure in Interventional Fluoroscopy With Eye Tracking Technology.

OBJECTIVES: Reducing avoidable radiation exposure during medical procedures is a top priority. The purpose of this study was to quantify, for the first time, the percentage of avoidable radiation during fluoroscopically guided cardiovascular interventions using eye tracking technologies. MATERIALS AND METHODS: Mobile eye tracking glasses were used to measure precisely when the operators looked at a fluoroscopy screen during the interventions. A novel machine learning algorithm and image processing techniques were used to automatically analyze the data and compute the percentage of avoidable radiation. Based on this percentage, the amount of potentially avoidable radiation dose was computed. RESULTS: This study included 30 cardiovascular interventions performed by 5 different operators. A significant percentage of the administered radiation (mean [SD], 43.5% [12.6%]) was avoidable (t29 = 18.86, P < 0.00001); that is, the operators were not looking at the fluoroscopy screen while the x-ray was on. On average, this corresponded to avoidable amounts of air kerma (mean [SD], 229 [66] mGy) and dose area product (mean [SD], 32,781 [9420] mGycm), or more than 11 minutes of avoidable x-ray usage, per procedure. CONCLUSIONS: A significant amount of the administered radiation during cardiovascular interventions is in fact avoidable.

Feasibility and Safety of Cerebral Embolic Protection Device Insertion in Bovine Aortic Arch Anatomy.

BACKGROUND: Cerebral embolic protection devices (CEPDs) have emerged as a mechanical barrier to prevent debris from reaching the cerebral vasculature, potentially reducing stroke incidence. Bovine aortic arch (BAA) is the most common arch variant and represents challenge anatomy for CEPD insertion during transcatheter aortic valve replacement (TAVR). METHODS: Cohort study reporting the SentinelTM Cerebral Protection System insertion's feasibility and safety in 165 adult patients submitted to a transfemoral TAVR procedure from April 2019 to April 2020. Patients were divided into 2 groups: (1) BAA; (2) non-BAA. RESULTS: Median age, EuroScore II, and STS score were 79 years (74-84), 2.9% (1.7-6.2), and 2.2% (1.6-3.2), respectively. BAA was present in 12% of cases. Successful two-filter insertion was 86.6% (89% non-BAA vs. 65% BAA; p = 0.002), and debris was captured in 95% (94% non-BAA vs. 95% BAA; p = 0.594). No procedural or vascular complications associated with Sentinel insertion and no intraprocedural strokes were reported. There were two postprocedural non-disabling strokes, both in non-BAA. CONCLUSION: This study demonstrated Sentinel insertion feasibility and safety in BAA. No procedural and access complications related to Sentinel deployment were reported. Being aware of the bovine arch prevalence and having the techniques to navigate through it allows operators to successfully use CEPDs in this anatomy.

Novel augmented physical simulator for the training of transcatheter cardiovascular interventions.

BACKGROUND: Training in transcatheter cardiovascular skills today represents a significant challenge because of the complexity of the interventions and an extensive use of multiple live imaging technologies. OBJECTIVES: We describe the design, the face validation, and content validation of a newly developed physical transseptal puncture (TSP) simulator using additive manufacturing techniques and novel imaging simulation solutions. METHODS: The TSP simulator contains a femoral vein catheterization pad, silicon phantoms of the venous system, a replaceable interatrial septum, and cameras to mimic live fluoroscopic and echocardiographic imaging. A validation study was conducted at the University Hospital of Zurich. A total of 14 interventional cardiologists and cardiac surgeons assessed the TSP simulator. Participants performed a TSP on the simulator using standard interventional tools. Face and content validity was demonstrated using a 5-point Likert scale. RESULTS: The TSP simulator is a new training tool for transcatheter cardiovascular interventions. All interventional cardiologists and cardiac surgeons completed the training exercise and scoring. Overall impression was rated (out of 5) 4.04 ± 1.03, haptic feedback scored 4.13 ± 0.82, and the realism of fluoroscopy simulation 4.39 ± 0.79. Usability was rated 4.50 ± 0.63 by the participants, indicating that the simulator could be suitable for training. CONCLUSION: We demonstrated face and content validity of a new simulator for transcatheter cardiovascular interventions. The TSP simulator's usability, haptic feedback, imaging solutions, and the overall impression of its usage were reported as very realistic. The TSP simulator represents a promising tool for simulation-based training using real interventional toolkits in a mimicked radiological environment.

Visual Behaviour Strategies of Operators during Catheter-Based Cardiovascular Interventions.

The aim was to gain insights into the visual behaviour and the perceptual skills of operators during catheter-based cardiovascular interventions (CBCVIs). A total of 33 CBCVIs were performed at the University Hospital Zurich by five operators, two experts and three novices, while wearing eye tracking glasses. The visual attention distribution on three areas of interest (AOIs) the "Echo screen", "Fluoro screen" and "Patient" was analysed for the transseptal puncture procedure. Clear visual behaviour patterns were observable in all cases. There is a significant differences in visual attention distribution of the experts compared to the novices. Experts spent 79% of dwell time on the Echo screen and 17% on the Fluoro screen, novices spent 52% on the Echo screen and 40% on the Fluoro screen. Additionally, results showed that experts focused their gaze on smaller areas than novices during critical interventional actions. Operators seem to exhibit identifiable visual behaviour patterns for CBCVIs. These identifiable patterns were significantly different between the expert and the novice operators. This indicates that the visual behaviour of operators could be employed to assist transfer of experts' perceptual skills to novices and to develop tools for objective performance assessment.

The Impact of Size and Position of a Mechanical Expandable Transcatheter Aortic Valve: Novel Insights Through Computational Modelling and Simulation.

Transcatheter aortic valve implantation has become an established procedure to treat severe aortic stenosis. Correct device sizing/positioning is crucial for optimal outcome. Lotus valve sizing is based upon multiple aortic root dimensions. Hence, it often occurs that two valve sizes can be selected. In this study, patient-specific computer simulation is adopted to evaluate the influence of Lotus size/position on paravalvular aortic regurgitation (AR) and conduction abnormalities, in patients with equivocal aortic root dimensions. First, simulation was performed in 62 patients to validate the model in terms of predicted AR and conduction abnormalities using postoperative echocardiographic, angiographic and ECG-based data. Then, two Lotus sizes were simulated at two positions in patients with equivocal aortic root dimensions. Large valve size and deep position were associated with higher contact pressure, while only large size, not position, significantly reduced the predicted AR. Despite general trends, simulations revealed that optimal device size/position is patient-specific.

Surgical correction of anomalous origin of the right coronary artery from the left sinus of Valsalva: How, where, and when.

Anomalous origin of the right coronary artery from the left sinus of Valsalva has a very low prevalence in the general population. Although the vast majority of patients are asymptomatic, the clinical consequence of this heart disorder can be sudden death. In many of these sudden death cases the right coronary artery is running between the anterior aspect of the aorta and behind the common trunk of the pulmonary artery, where systolic compression may have an impact on myocardial perfusion. Asymptomatic patients with this malignant course present the surgeon with a difficult decision, and they should be carefully evaluated in order to facilitate a tailored surgical approach.  In this video tutorial we present a patient with this anomalous course of the right coronary artery, which was documented by coronary computed tomography angiography using a 3D reconstruction. The patient received an off-pump coronary artery bypass graft using an original surgical technique that prevents any type of flow competition. The case had an excellent final outcome, with good results at follow-up.  Finally, a systematic review of the literature with a discussion of the different treatment modalities is provided.

Application of cryoenergy to improve septal exposure during transaortic septal myectomy in hypertrophic obstructive cardiomyopathy.

For the past few decades, the transaortic septal myectomy (Morrow's procedure) has been the gold standard for treating severe left ventricular outflow tract obstruction in hypertrophic obstructive cardiomyopathy (HOCM) patients. 30-day mortality has been reported at less than 1% in dedicated centers. However, in a subgroup of patients, the interventricular septal obstruction is localized very distally, below the aortic valve plane, and the transaortic approach can be very challenging. A subset of these patients can present with residual obstruction after surgery, due to inadequate length of septal excision, leading to reoperation. The aim of this work is to illustrate an original application of cryoenergy to improve the transaortic exposure of the interventricular septum and thus enable surgeons to perform very distal myectomies in HOCM patients.

Systolic anterior motion after mitral valve repair: a predictive computational model.

OBJECTIVES: Systolic anterior motion (SAM) can be an insidious complication after mitral repair. Predicting SAM represents a challenge, even for very experienced mitral valve surgeons. The goal of this pilot work was to illustrate for the first time, a computational software able to calculate and prevent SAM during mitral repair. METHODS: Using MATLAB graphical user interface, a clinical software to predict SAM, we tested the performances of the software on 136 patients with degenerative mitral valves undergoing repair with standard techniques. A combination of 6 key echocardiographic parameters was used to calculate the SAM risk score. The discriminative performance of the model was assessed by the area under the receiver-operating characteristic curve. The receiver-operating characteristic was used to divide patients into low, medium and high risk for SAM. Simulation of virtual mitral repair (posterior leaflet resection and mitral ring annuloplasty) was also tested to reduce the risk of SAM. RESULTS: The incidence of SAM was 8.1%; 73% were detected as high risk by the software. The area under the receiver-operating characteristic model discriminant performance was 0.87 (95% confidence interval: 0.78-0.95). Simulating a posterior leaflet resection with the leaflet length fixed at 15 mm, the estimated SAM risk was updated, and all patients were then classified at low risk. CONCLUSIONS: This software is the first computational model designed to predict SAM during mitral repair to show excellent discrimination. This software has the potential to predict SAM risk preoperatively and, after a virtual step-by-step mitral repair simulation, depending on the technique adopted, to always achieve a low-risk SAM profile.

Minimally invasive or conventional edge-to-edge repair for severe mitral regurgitation due to bileaflet prolapse in Barlow's disease: does the surgical approach have an impact on the long-term results?

OBJECTIVES: To evaluate whether the adoption of a right minithoracotomy operative approach had an impact on the long-term results of edge-to-edge (EE) repair compared to conventional sternotomy in patients with Barlow's disease and bileaflet prolapse. METHODS: We assessed the long-term results of 104 patients with Barlow's disease treated with a minimally invasive EE technique. An equal number of patients had a conventional median sternotomy EE repair for the same disease and were used as a control group. The inverse probability of treatment weighting was used to create comparable distributions of the covariates that were significantly different at baseline in the two groups. We performed a comparative analysis of the groups. RESULTS: No hospital deaths were observed. Follow-up was 99.5% complete (median 11.3 years). The cumulative incidence function (CIF) of cardiac death at 12 years, with noncardiac death as a competing risk, showed no difference between the two groups ( P = 0.87). At 12 years, the CIF of recurrent MR ≥ 3+, with death as the competing risk, was 7% in the sternotomy group and 5% in the minimally invasive group ( P = 0.30), and the CIF of recurrence of MR ≥ 2+ was 15 and 14%, respectively ( P = 0.63). The type of surgical approach was not a predictor of cardiac death, reoperation, recurrent MR ≥ 3+ or recurrent MR ≥ 2+. CONCLUSIONS: A minimally invasive approach does not have a negative impact on the effectiveness and long-term durability of the EE repair for bileaflet prolapse in Barlow's disease. Long-term outcomes are excellent, and valvular performance remains stable over time with no evidence of mitral stenosis.

Long-term results (up to 14 years) of the clover technique for the treatment of complex tricuspid valve regurgitation.

OBJECTIVES: To report the long-term results of the clover technique for the treatment of complex forms of tricuspid regurgitation (TR). METHODS: Ninety-six consecutive patients (mean age 60 ± 16.4, left ventricular ejection fraction 58 ± 8.8%) with severe or moderately-severe TR due to important leaflets prolapse/flail (81 patients), tethering (13 patients) or mixed (2 patients) lesions underwent clover repair combined with annuloplasty. The aetiology of TR was degenerative in 74 cases (77.1%), post-traumatic in 9 (9.4%) and secondary to dilated cardiomyopathy in 13 (13.5%). All patients but 3 (96.8%) underwent ring (59 patients, 61.5%) or suture (34 patients, 35.4%) annuloplasty. Concomitant procedures (mainly mitral surgery) were performed in 82 patients (85.4%). RESULTS: Hospital mortality was 7.2%. At hospital discharge 92 (95.8%) patients had no or mild TR. Follow-up was 98% complete (median 9 years, interquartile range 5.1; 10.9). At 12 years the overall survival was 71.6 ± 7.22% and the cumulative incidence function of cardiac death with non-cardiac death as competing risk 16 ± 4.1% [95% confidence interval (95% CI) 9.5-25.7]. At 12 years the cumulative incidence function of TR ≥ 3+ and TR ≥ 2+ with death as competing risk were 1.2 ± 1.2% (95% CI 0.1-5.8) and 28 ± 7.7% (95% CI 14.3-43.5), respectively. Preoperative left ventricular ejection fraction (hazard ratio 0.9, CI 0.9-1, P = 0.05) and previous cardiac surgery (hazard ratio 2.7, 95% CI 1-7.1, P = 0.03) were predictors of recurrent TR ≥ 2+ at univariable but not at multivariable analysis. CONCLUSIONS: Complex forms of TR due to severe prolapse or tethering of the leaflets can be effectively treated with the clover technique with very satisfactory long-term results and extremely low recurrence of severe TR.

Mid-term outcomes of concomitant surgical ablation of atrial fibrillation in patients undergoing cardiac surgery for hypertrophic cardiomyopathy†.

OBJECTIVES: Atrial fibrillation (AF) is common in patients with hypertrophic cardiomyopathy (HCM) and it is often poorly tolerated because of loss of atrial contraction and reduced filling time with rapid ventricular rates. Restoring sinus rhythm is of great clinical benefit to HCM patients. Very few data exist regarding surgical ablation of concomitant AF in this setting. The aim of this study was to evaluate the mid-term outcome of surgical AF ablation in patients who underwent cardiac surgery due to HCM. METHODS: Thirty-one consecutive patients with primary HCM and drug-refractory symptomatic AF underwent surgical ablation with concomitant septal myectomy (77%) and/or mitral valve repair/replacement (39%). Follow-up was 97% complete with a median of 6.4 years [3.8-9.1]. RESULTS: Hospital mortality was 6% and the overall survival at 7 years was 87 ± 6.1%. No stroke and thromboembolic events were documented at follow-up. The arrhythmia-free survival off antiarrhythmic drugs was 82 ± 7.3% at 1 year and 52 ± 10.2% at 6 years. The 1- and 6-year arrhythmia control (maintenance of sinus rhythm with or without antiarrhythmic drugs) was 96 ± 3.5 and 80 ± 8.1%, respectively. The recurrent arrhythmia was AF in all patients. No predictors of AF recurrence were detected. CONCLUSIONS: Concomitant surgical ablation of AF is a reasonable treatment option for drug refractory AF in patients with HCM undergoing surgical myectomy and/or mitral valve surgery. However, chronic antiarrhythmic drugs are needed to achieve a satisfactory mid-term arrhythmia control.

Does implantation of a single clip provide reliable durability after transcatheter mitral repair?

OBJECTIVES: A single MitraClip implant is often considered enough to achieve adequate mitral regurgitation (MR) reduction. The aim of this study was to compare MR recurrence in patients with an initial optimal result treated with a single clip versus those treated with two clips. METHODS: From October 2008 to May 2016, 322 patients were treated with the MitraClip procedure at our institution. We retrospectively selected all patients treated for functional MR (FMR) and degenerative MR (DMR) aetiologies with residual MR ≤1+, excluding patients who required >2 clips. FMR and DMR were analysed separately. RESULTS: In FMR, a single clip was used in 45 patients and 2 clips in 99 patients. The single clip group had smaller coaptation depth (1.1 ± 0.3 vs 1.3 ± 0.3 mm, P = 0.022) and jet extension (10.5 ± 2.1 vs 13.0 ± 3.6 mm, P = 0.026) as well as left ventricular end-diastolic diameter (64.4 ± 7.3 vs 69.0 ± 7.9 mm, P = 0.001). Freedom from MR ≥ 3+ after 4 years was 71.9 ± 8.9% in patients receiving a single clip vs 88.0 ± 5.2% in those receiving 2 clips, single clip use being an independent predictor of MR recurrence (HR 3.48, CI 1.24-9.81, P = 0.018). In DMR, a single clip was deployed in 24 patients and 2 clips in 30 patients. The single clip group had a smaller flail gap (3.6 ± 0.7 vs 6.8 ± 2.5, P = 0.002). Freedom from MR ≥ 3+ after 2 years was 82.5 ± 8% in patients with a single clip vs 100% in those with 2 clips, P = 0.014. The residual mitral area was reduced in patients with 2 clips compared with those with single clip, both in FMR ( P = 0.015) and DMR ( P = 0.039), but it was not associated with increased death rate during the follow-up period (all P > 0.05). CONCLUSIONS: Despite favourable anatomical characteristics and an optimal initial result, implantation of a single clip was associated with an increased recurrence of MR compared with that of 2 clips, both in FMR and in DMR. Caution should be exercised with the implantation of a single clip.

Results of tricuspid valve surgery for functional tricuspid regurgitation: acute and long-term outcomes and predictors of failure.

The assessment and management of tricuspid valve (TV) disease evolved significantly in the last decade. Tricuspid regurgitation (TR) is a frequent heart valve disease and it is most often secondary, due to annular dilatation and leaflet tethering from right ventricular remodeling. The indications for TV surgery are several and mainly related to the underlying disease, to the severity of the regurgitation and to the right ventricular function. Moreover, surgical tricuspid repair has been avoided for years, because of the erroneous concept that TR should disappear once the primary pathology on the left heart has been resolved. Instead, during the last few years, many investigators have reported evidence in favor of a more aggressive surgical approach to functional TR, recognizing the risk of progressive tricuspid insufficiency in patients with annular dilatation and only moderate regurgitation (or less) at the time of surgery. This concept, along with the acute and long-term outcomes of tricuspid surgical repair techniques and tricuspid replacement are discussed in this review.