Image-guided port placement for minimally invasive cardiac surgery

Minimally invasive surgery is becoming popular for a number of interventions. Use of robotic surgical systems in coronary artery bypass intervention offers many benefits to patients, but is however limited by remaining challenges in port placement. Choosing the entry ports for the robotic tools has a large impact on the outcome of the surgery, and can be assisted by pre-operative planning and intra-operative guidance techniques. In this thesis, pre-operative 3D computed tomography (CT) imaging is used to plan minimally invasive robotic coronary artery bypass (MIRCAB) surgery. From a patient database, port placement optimization routines are implemented and validated. Computed port placement configurations approximated past expert chosen configurations with an error of 13.7 ±5.1 mm. Following optimization, statistical classification was used to assess patient candidacy for MIRCAB. Various pattern recognition techniques were used to predict MIRCAB success, and could be used in the future to reduce conversion rates to conventional open-chest surgery. Gaussian, Parzen window, and nearest neighbour classifiers all proved able to detect ‘candidate’ and ‘non-candidate’ MIRCAB patients. Intra-operative registration and laser projection of port placements was validated on a phantom and then evaluated in four patient cases. An image-guided laser projection system was developed to map port placement plans from pre-operative 3D images. Port placement mappings on the phantom setup were accurate with an error of 2.4 ± 0.4 mm. In the patient cases, projections remained within 1 cm of computed port positions. Misregistered port placement mappings in human trials were due mainly to the rigid-body registration assumption and can be improved by non-rigid techniques. Overall, this work presents an integrated approach for: 1) pre-operative port placement planning and classification of incoming MIRCAB patients; and 2) intra-operative guidance of port placement. Effective translation of these techniques to the clinic will enable MIRCAB as a more efficacious and accessible procedure

Robotic totally endoscopic coronary artery bypass: A word of caution implicated by a five-year follow-up

ObjectiveRobotic totally endoscopic coronary artery bypass of the left anterior descending artery has been introduced in the clinical setting using a wrist-enhanced computer-assisted device to provide a minimally invasive therapeutic approach. Early clinical results were focused on the initial hospital course of patients. This report describes the first 5-year follow-up of patients after totally endoscopic coronary artery bypass in a single center.MethodsFrom May 1999 to June 2001, 41 patients (36 male, 5 female; mean age 60.6 ± 8.9 years) underwent totally endoscopic coronary artery bypass for isolated high-grade lesions of the left anterior descending coronary artery by means of the da Vinci system (Intuitive Surgical, Inc, Mountain View, Calif). Clinical follow-up was performed 5 years after the operation. End points of the follow-up were freedom from major adverse events such as death, myocardial infarction, and repeated revascularization of the left anterior descending artery.ResultsHospital survival was 100%. Overall survival after 5 years was 92.7% (38/41 patients). Three (7.3%) patients died of noncardiac causes. Freedom from reintervention of the left anterior descending artery after a mean of 69 ± 7.4 months was 87.2% (36/41 patients). Freedom from any major adverse events during the whole follow-up was 75.7% (31/41 patients).ConclusionEndoscopic surgery on the beating heart remains the ultimate goal for minimally invasive coronary artery surgery. The clinical outcomes and need for reintervention of the target vessel leave room for improvement and may be considered reflective of early experiences typically associated with dramatic departure from conventional therapy. Moving forward, advances in instrumentation and anastomotic technology seem to be essential for reproducible and reliable coronary anastomosis in a totally endoscopic approach

The Role of Visualization, Force Feedback, and Augmented Reality in Minimally Invasive Heart Valve Repair

New cardiovascular techniques have been developed to address the unique requirements of high risk, elderly, surgical patients with heart valve disease by avoiding both sternotomy and cardiopulmonary bypass. However, these technologies pose new challenges in visualization, force application, and intracardiac navigation. Force feedback and augmented reality (AR) can be applied to minimally invasive mitral valve repair and transcatheter aortic valve implantation (TAVI) techniques to potentially surmount these challenges. Our study demonstrated shorter operative times with three dimensional (3D) visualization compared to two dimensional (2D) visualization; however, both experts and novices applied significantly more force to cardiac tissue during 3D robotics-assisted mitral valve annuloplasty than during conventional open mitral valve annuloplasty. This finding suggests that 3D visualization does not fully compensate for the absence of haptic feedback in robotics-assisted cardiac surgery. Subsequently, using an innovative robotics-assisted surgical system design, we determined that direct haptic feedback may improve both expert and trainee performance using robotics-assisted techniques. We determined that during robotics-assisted mitral valve annuloplasty the use of either visual or direct force feedback resulted in a significant decrease in forces applied to cardiac tissue when compared to robotics-assisted mitral valve annuloplasty without force feedback. We presented NeoNav, an AR-enhanced echocardiograpy intracardiac guidance system for NeoChord off-pump mitral valve repair. Our study demonstrated superior tool navigation accuracy, significantly shorter navigation times, and reduced potential for injury with AR enhanced intracardiac navigation for off-pump transapical mitral valve repair with neochordae implantation. In addition, we applied the NeoNav system as a safe and inexpensive alternative imaging modality for TAVI guidance. We found that our proposed AR guidance system may achieve similar or better results than the current standard of care, contrast enhanced fluoroscopy, while eliminating the use of nephrotoxic contrast and ionizing radiation. These results suggest that the addition of both force feedback and augmented reality image guidance can improve both surgical performance and safety during minimally invasive robotics assisted and beating heart valve surgery, respectively

COVID-19 and the Digitalisation of Cardiovascular Training and Education—A Review of Guiding Themes for Equitable and Effective Post-graduate Telelearning

The coronavirus disease-2019 (COVID-19) pandemic has had an unprecedented impact leading to novel adaptations in post-graduate medical education for cardiovascular and general internal medicine. Whilst the results of initial community COVID-19 vaccination are awaited, continuation of multimodality teaching and training that incorporates telelearning will have enduring benefit to post-graduate education and will place educational establishments in good stead to nimbly respond in future pandemic-related public health emergencies. With the rise in innovative virtual learning solutions, medical educators will have to leverage technology to develop electronic educational materials and virtual courses that facilitate adult learning. Technology-enabled virtual learning is thus a timely progression of hybrid classroom initiatives that are already adopted to varying degrees, with a need for faculty to serve as subject matter experts, to host and moderate online discussions, and to provide feedback and overall mentorship. As an extension from existing efforts, simulation-based teaching (SBT) and learning and the use of mixed reality technology should also form a greater core in the cardiovascular medicine curriculum. We highlight five foundational themes for building a successful e-learning model in cardiovascular and general post-graduate medical training: (1) digital solutions and associated infrastructure; (2) equity in access; (3) participant engagement; (4) diversity and inclusion; and (5) patient confidentiality and governance framework. With digitalisation impacting our everyday lives and now how we teach and train in medicine, these five guiding principles provide a cognitive scaffold for careful consideration of the required ecosystem in which cardiovascular and general post-graduate medical education can effectively operate. With due consideration of various e-learning options and associated infrastructure needs; and adoption of strategies for participant engagement under sound and just governance, virtual training in medicine can be effective, inclusive and equitable through the COVID-19 era and beyond

Use of extended realities in cardiology

Recent miniaturization of electronic components and advances in image processing software have facilitated the entry of extended reality technology into clinical practice. In the last several years, the number of applications in cardiology has multiplied, with many promising to become standard of care. We review many of these applications in the areas of patient and physician education, cardiac rehabilitation, pre-procedural planning and intraprocedural use. The rapid integration of these approaches into the many facets of cardiology suggests that they will one day become an every-day part of physician practice

Extracorporeal Circulation in Cardiac Surgery Inflammatory response, controversies and Future Directions

One of the milestones in the history of the cardiac surgery is the development of extracorporeal circulation, which allowed hundreds of thousands of patients under successful open cardiac surgery. It´s objective is to maintain the vital organ´s perfusion, provide a bloodless field for surgery, and at the same time, give protection to the heart and lungs. Its principle is to bring most or all of the patient’s systemic blood, which normally returns to the right atrium, into an oxygenator in which oxygen is supplied to the blood and carbon dioxide is removed. The arterialized blood is filtered, heated and, pumped into the aorta and the systemic arterial system. But this continuous blood recirculation through nonendothelial surfaces of the perfusion system produces an inflammatory response. Despite all the advantages and strategies developed to try to make the most physiological condition during the extracorporeal circulation, there are still persistent controversies, which we are going to review, as well as the inflammatory response produced by the perfusion system, and it´s future directions