Catheter-based Technology Research Articles

The motivators and barriers to a career in cardiothoracic surgery: a cross-sectional study among surgical residents in India.

A consistent decline in the number of applicants to cardiothoracic and vascular surgery (CTVS) training programs has been observed across the country over the last few years. This disenchantment with the speciality will lead to a shortage of trained CTVS surgeons at a time when incidence of cardiovascular diseases is continuously rising in India. The aim of the study was to reflect on the reasons that averted applicants from pursuing a career in CTVS and measures that would make CTVS a more attractive option to future applicants. An online nationwide prospective cross-sectional survey was conducted. The participants were from a pool of general surgery residents/residents who had just completed the training. A 5-point Likert scale was utilized to rate and evaluate the factors influencing CTVS as the primary choice, factors influencing any super-speciality, and factors that would aid in decision-making and encourage an interest in CTVS. A total of 618 responses were obtained, 25.6% (N = 158) of the responses were from female residents. Only 10.7% (N = 66) of the respondents wanted to pursue CTVS as their primary choice. While interest in CTVS among the 1st year residents was 26%, it was further observed to decline to 18.72% after completion of training. The main disincentives for pursuing CTVS were the need for a hospital with required infrastructure and the dependence on a multi-disciplinary team. The perception of the participants that the cardiologist will take over CTVS procedures was another misguided but important factor. Those residents interested in pursuing CTVS identified the dynamic nature of the speciality as well as the thrills of being a cardiac surgeon as important motivators. Participants felt that adding catheter-based technology to the CTVS curriculum, mandatory CTVS rotation during surgical training, and closer interaction with CTVS residents will generate more interest in CTVS. Although surgical residents report early interest in CTVS, a lack of adequate exposure to the speciality leads to a decline in interest in CTVS. An overhaul of the surgical training that mandates rotating to CTVS, increased interactions with medical students and surgical trainees by CTVS faculty, and incorporation of catheter-based training in the CTVS syllabus is urgently required to increase the number of applicants to CTVS. The online version contains supplementary material available at 10.1007/s12055-022-01406-2.

Mental rotation ability predicts the acquisition of basic endovascular skills

Due to the increasing complexity of diseases in the aging population and rapid progress in catheter-based technology, the demands on operators’ skills in conducting endovascular interventions (EI) has increased dramatically, putting more emphasis on training. However, it is not well understood which factors influence learning and performance. In the present study, we examined the ability of EI naïve medical students to acquire basic catheter skills and the role of pre-existing cognitive ability and manual dexterity in predicting performance. Nineteen medical students practised an internal carotid artery angiography during a three-day training on an endovascular simulator. Prior to the training they completed a battery of tests. Skill acquisition was assessed using quantitative and clinical performance measures; the outcome measures from the test battery were used to predict the learning rate. The quantitative metrics indicated that participants’ performance improved significantly across the training, but the clinical evaluation revealed that participants did not significantly improve on the more complex part of the procedure. Mental rotation ability (MRA) predicted quantitative, but not clinical performance. We suggest that MRA tests in combination with simulator sessions could be used to assess the trainee’s early competence level and tailor the training to individual needs.

Renal Denervation in Hypertension.

The column in this issue is supplied by Drs. Benjamin Lee, MD, and Usman Ansari, DO. Dr. Lee is an assistant professor of clinical medicine at the Houston Methodist Institute for Academic Medicine and Weill Cornell Medical College. After earning his medical degree at Harvard Medical School, Dr. Lee completed a residency in internal medicine and a nephrology fellowship at the University of California San Francisco (UCSF) while simultaneously obtaining a master of advanced study in clinical research from the UCSF departments of Epidemiology and Biostatistics. He maintains his clinical practice with the Houston Kidney Consultants. Dr. Ansari earned a Doctor of Osteopathy from Touro University College of Osteopathic Medicine in California and is completing his internal medicine residency at Houston Methodist.

The sutureless and rapid-deployment aortic valve replacement international registry: lessons learned from more than 4,500 patients.

The treatment options for patients with aortic valve disease have considerably expanded over the last decade. The remarkable advances in catheter-based technology, the popularizing of minimally invasive (MI) surgery, and the introduction of new valve technologies, such as sutureless and rapid-deployment (SURD) valves have led to a paradigm shift in the management of aortic valve pathologies. Yet, given their recent introduction, the current evidence on sutureless and rapid-deployment aortic valve replacement (SURD-AVR) has been limited thus far. The Sutureless and Rapid-Deployment Aortic Valve Replacement International Registry (SURD-IR) was established in 2015 by a consortium of 18 research centers to assess safety, efficacy, short- and long-term outcomes of SURD-AVR interventions. The present keynote lecture aims to assess and comment on the real-world evidence for SURD-AVR surgery generated from the SURD-IR.

Resuscitative endovascular balloon occlusion of the aorta in pelvic ring fractures: The Denver Health protocol

Patients presenting with hemodynamic instability associated with pelvic fractures continue to have very high mortality and surgeons continue to seek damage control strategies that may improve survival. Strategies usually require massive transfusion, immediate pelvic stabilization and another adjunctive maneuver's such as angioembolization or preperitoneal pelvic packing to prevent hemorrhagic death. One current intervention that has regained some popularity in lieu of resuscitative thoracotomy is the Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA). This requires some manner of femoral arterial access to insert a balloon into the aorta and increase central blood pressure (cardiac and cerebral perfusion) and control active pelvic bleeding. Based on several animal models and an increasing number of publications, many US level I trauma centers have now opted to use REBOA in carefully selected patients showing signs of near cardiac arrest from non-compressible torso hemorrhage. Description of the current advances in aortic occlusion using catheter-based technology in the setting of severe shock for non-compressible torso hemorrhage from pelvic ring fracture is the purpose of this report.

Cardiac Autonomic Nerves Stimulation Improves Hemodynamics: A Pilot Study in Advanced Heart Failure Patients

Purpose Despite therapy advances in heart failure management, symptomatic congestion in acute heart failure is a leading cause of mortality and morbidity. An electrode catheter-based technology, cardiac autonomic nerve stimulation (CANS), is being investigated to transvenously stimulate cardiac autonomic nerves to control left-ventricular contractility and heart rate (HR). Methods The study was a single-center, clinical investigation to observe CANS effects on in-hospital hemodynamics and signs and symptoms of congestion. Five subjects with reduced left ventricular ejection fraction (LVEF Results Most subjects were male (3/5), had a mean age of 65 years, mean NT-proBNP of 3622 pg/mL and a mean Pulmonary Capillary Wedge Pressure (PCWP) of 30 mmHg. CANS was provided for a mean of 18 hours and was well tolerated. There were no adverse events reported. Mean LVEF increased in all subjects (27% to 35%) over the stimulation period. In three subjects, CANS directly modulated arterial pulse pressure (12% mean change) with a neutral HR effect ( Conclusion Alongside concomitant medical therapy, CANS directly improved hemodynamics and was associated with improved signs and symptoms of congestion. These improvements, and no adverse events, demonstrate that CANS holds promise as a tool to improve in-hospital hemodynamics and congestion. Future study is warranted to investigate CANS Therapy for longer stimulation duration, in expanded patient phenotypes, in more subjects.

Contemporary Use of Intracoronary Imaging in Percutaneous Coronary Intervention

Since the first balloon angioplasty in 1977, remarkable advances in catheter-based technology have been achieved with the use of stents and intracoronary devices. However, despite these developments, visual assessment of a 2-dimensional lumenogram of the coronary vessels remains the predominant method of assessing coronary disease and guiding angioplasty worldwide. It is an enigma that there is still such a low uptake in the use of intravascular imaging, whether in the form of intravascular ultrasound (IVUS) or optical coherence tomography (OCT), with both techniques providing cross-sectional imaging of the coronary vessels with a resolution at the microscopic scale. The intracoronary imaging community tends to focus on the academic aspects of IVUS and OCT, often highlighting the evidence-based benefits in lesion subsets, such as left main stem or bifurcation percutaneous coronary intervention. However, this does not impart crucial practical-related aspects pertaining to IVUS or OCT, which can improve outcomes and achieve optimal results for operators and patients. Here, the authors present a case-based approach to IVUS and OCT use in contemporary clinical practice, with the hope of providing useful, practical insights for the busy interventionalist and prompting the consideration of intracoronary imaging catheters as an essential part of their percutaneous coronary intervention toolbox.

Reasons for conversion and adverse intraoperative events in Endoscopic Port Access™ atrioventricular valve surgery and minimally invasive aortic valve surgery.

This study reports the factors that contribute to sternotomy conversions (SCs) and adverse intraoperative events in minimally invasive aortic valve surgery (MI-AVS) and minimally invasive Endoscopic Port Access™ atrioventricular valve surgery (MI-PAS). In total, 3780 consecutive patients with either aortic valve disease or atrioventricular valve disease underwent minimally invasive valve surgery (MIVS) at our institution between 1 February 1997 and 31 March 2016. MI-AVS was performed in 908 patients (mean age 69.2 ± 11.3 years, 45.2% women, 6.2% redo cardiac surgery) and MI-PAS in 2872 patients (mean age 64.1 ± 13.3 years, 46.7% women, 12.2% redo cardiac surgery). A cumulative total of 4415 MIVS procedures (MI-AVS = 908, MI-PAS = 3507) included 1537 valve replacements (MI-AVS = 896, MI-PAS = 641) and 2878 isolated or combined valve repairs (MI-AVS = 12, MI-PAS = 2866). SC was required in 3.0% (n = 114 of 3780) of MIVS patients, which occurred in 3.1% (n = 28 of 908) of MI-AVS patients and 3.0% (n = 86 of 2872) of MI-PAS patients, respectively. Reasons for SC in MI-AVS included inadequate visualization (n = 4, 0.4%) and arterial cannulation difficulty (n = 7, 0.8%). For MI-PAS, SC was required in 54 (2.5%) isolated mitral valve procedures (n = 2183). Factors that contributed to SC in MI-PAS included lung adhesions (n = 35, 1.2%), inadequate visualization (n = 2, 0.1%), ventricular bleeding (n = 3, 0.1%) and atrioventricular dehiscence (n = 5, 0.2%). Neurological deficit occurred in 1 (0.1%) and 3 (3.5%) MI-AVS and MI-PAS conversions, respectively. No operative or 30-day mortalities were observed in MI-AVS conversions (n = 28). The 30-day mortality associated with SC in MI-PAS (n = 86) was 10.5% (n = 9). MIVS is increasingly being recognized as the 'gold-standard' for surgical valve interventions in the context of rapidly expanding catheter-based technology and increasing patient expectations. Surgeons need to be aware of factors that contribute to SC and adverse intraoperative outcomes to ensure that patients enjoy the maximum potential benefit of MIVS and to apply effective risk reduction strategies that encourage safer and sustainable MIVS programmes.

Transcatheter mitral valve replacement

Mitral valve disease is a growing clinical problem. Surgical mitral valve repair and replacement remains the treatment of choice with excellent long-term clinical outcomes. However, a large number of symptomatic patients were deemed too high-risk undergoing surgical correction. Catheter-based technology has been in development to address this unmet need. Transcatheter mitral valve replacement devices are such technology and are currently undergoing clinical investigation. A systematic overview is being presented in the article.

Recent advances in rhythm control for atrial fibrillation.

Atrial fibrillation (AF) remains a difficult management problem. The restoration and maintenance of sinus rhythm—rhythm control therapy—can markedly improve symptoms and haemodynamics for patients who have paroxysmal or persistent AF, but some patients fare well with rate control alone. Sinus rhythm can be achieved with anti-arrhythmic drugs or electrical cardioversion, but the maintenance of sinus rhythm without recurrence is more challenging. Catheter ablation of the AF triggers is more effective than anti-arrhythmic drugs at maintaining sinus rhythm. Whilst pulmonary vein isolation is an effective strategy, other ablation targets are being evaluated to improve sinus rhythm maintenance, especially in patients with chronic forms of AF. Previously extensive ablation strategies have been used for patients with persistent AF, but a recent trial has shown that pulmonary vein isolation without additional ablation lesions is associated with outcomes similar to those of more extensive ablation. This has led to an increase in catheter-based technology to achieve durable pulmonary vein isolation. Furthermore, a combination of anti-arrhythmic drugs and catheter ablation seems useful to improve the effectiveness of rhythm control therapy. Two large ongoing trials evaluate whether a modern rhythm control therapy can improve prognosis in patients with AF.

Training Standards in Neuroendovascular Surgery: Program Accreditation and Practitioner Certification.

Neuroendovascular surgery is a medical subspecialty that uses minimally invasive catheter-based technology and radiological imaging to diagnose and treat diseases of the central nervous system, head, neck, spine, and their vasculature. To perform these procedures, the practitioner needs an extensive knowledge of the anatomy of the nervous system, vasculature, and pathological conditions that affect their physiology. A working knowledge of radiation biology and safety is essential. Similarly, a sufficient volume of clinical and interventional experience, first as a trainee and then as a practitioner, is required so that these treatments can be delivered safely and effectively. This document has been prepared under the aegis of the Society of Neurological Surgeons and its Committee for Advanced Subspecialty Training in conjunction with the Joint Section of Cerebrovascular Surgery for the American Association of Neurological Surgeons and Congress of Neurological Surgeons, the Society of NeuroInterventional Surgery, and the Society of Vascular and Interventional Neurology. The material herein outlines the requirements for institutional accreditation of training programs in neuroendovascular surgery, as well as those needed to obtain individual subspecialty certification, as agreed on by Committee for Advanced Subspecialty Training, the Society of Neurological Surgeons, and the aforementioned Societies. This document also clarifies the pathway to certification through an advanced practice track mechanism for those current practitioners of this subspecialty who trained before Committee for Advanced Subspecialty Training standards were formulated. Representing neuroendovascular surgery physicians from neurosurgery, neuroradiology, and neurology, the above mentioned societies seek to standardize neuroendovascular surgery training to ensure the highest quality delivery of this subspecialty within the United States.

Modern cardiac surgery: the future of cardiac surgery in Australia.

Cardiac surgery is a relatively young specialty and is undergoing many changes presently. The advent of catheter-based technology, minimally invasive surgery and better information regarding the roles of cardiac surgery in the management of common cardiac disease is changing the way we provide services. In Australia, attention must be turned to the way cardiac surgical services are provided to enable delivery of modern procedures. This has implications for the provision of training. We explore the face of modern cardiac surgery and how this may be taken up in Australia.

A multi-center retrospective study on the clinical value of two generations of a single-operator cholangioscope: analysis of 191 applications in 162 patients

Background: Cholangioscopy provides direct visualization of the biliary tract by using ultra-slim endoscopes that can be introduced into the bile duct. The SpyGlass system is a catheter-based technology which can be used for diagnostic and therapeutic purposes by a single operator. Recently, a new generation of this technology has been launched.

Management of Coronary Artery Disease and Conduction Abnormalities in Transcatheter Aortic Valve Implantation.

Transcatheter aortic valve replacement (TAVR) is an expanding, catheter-based technology that allows the implantation of a prosthetic valve without requiring open heart surgery for the treatment of severe aortic stenosis (AS). The frequency of coronary artery disease (CAD) in patients (pts) with severe AS undergoing surgical treatment ranges from 30 to 50%. This tends to be higher in pts undergoing TAVR with a prevalence of 49-76% and is more prevalent with older age and the fact that TAVR is commonly performed in high-risk groups with more advanced cardiovascular disease. The overall influence of CAD on TAVR procedural outcomes remains controversial, and the management of concomitant artery disease is still under discussion. There are three major issues that must be addressed: the impact of CAD, optimal timing of percutaneous coronary intervention (PCI) and TAVR, and extent of revascularization. Today, TAVR is commonly performed as a stand-alone procedure with variable degrees of concomitant CAD tolerated without intervention. One of the major potential complications with TAVR is the damage to the conduction system. The requirement of permanent pacemaker (PM) implantation ranges from 9 to 49% of cases with a mean of ~20%, whereas surgical aortic valve replacement (sAVR) is associated with a complete heart block that requires permanent PM in 3-12% of cases. Reports have demonstrated an increased incidence of conduction damage in patients undergoing TAVR with the CoreValve (Medtronic Minneapolis, MN, USA) prosthesis (mean 20.8%, range 9.3-30.0%) compared with the Edwards SAPIEN (Edwards Lifesciences LLC; Irvine, CA, USA) prosthesis (mean 5.4%, range 0-10.1%). Factors predicting PM implantation include preexisting bundle branch block (BB) or conduction abnormalities. The prognostic significance of new left bundle branch block (LBBB) after TAVR is unclear. In the future, new valve designs may improve the incidence of permanent PM implantation after TAVR.

A light-reflecting balloon catheter for atraumatic tissue defect repair.

A congenital or iatrogenic tissue defect often requires closure by open surgery or metallic components that can erode tissue. Biodegradable, hydrophobic light-activated adhesives represent an attractive alternative to sutures, but lack a specifically designed minimally invasive delivery tool, which limits their clinical translation. We developed a multifunctional, catheter-based technology with no implantable rigid components that functions by unfolding an adhesive-loaded elastic patch and deploying a double-balloon design to stabilize and apply pressure to the patch against the tissue defect site. The device uses a fiber-optic system and reflective metallic coating to uniformly disperse ultraviolet light for adhesive activation. Using this device, we demonstrate closure on the distal side of a defect in porcine abdominal wall, stomach, and heart tissue ex vivo. The catheter was further evaluated as a potential tool for tissue closure in vivo in rat heart and abdomen and as a perventricular tool for closure of a challenging cardiac septal defect in a large animal (porcine) model. Patches attached to the heart and abdominal wall with the device showed similar inflammatory response as sutures, with 100% small animal survival, indicating safety. In the large animal model, a ventricular septal defect in a beating heart was reduced to <1.6 mm. This new therapeutic platform has utility in a range of clinical scenarios that warrant minimally invasive and atraumatic repair of hard-to-reach defects.

Optimal management of infrainguinal arterial occlusive disease.

Peripheral arterial occlusive disease is becoming a major health problem in Western societies as the population continues to age. In addition to risk of limb loss, the complexity of the disease is magnified by its intimate association with medical comorbidity, especially cardiovascular and cerebrovascular disease. Risk factor modification and antiplatelet therapy are essential to improve long-term survival. Surgical intervention is indicated for intermittent claudication when a patient’s quality of life remains unacceptable after a trial of conservative therapy. Open reconstruction and endovascular revascularization are cornerstone for limb salvage in patients with critical limb ischemia. Recent advances in catheter-based technology have made endovascular intervention the preferred treatment approach for infrainguinal disease in many cases. Nevertheless, lower extremity bypass remains an important treatment strategy, especially for reasonable risk patients with a suitable bypass conduit. In this review, we present a summary of current knowledge about peripheral arterial disease followed by a review of current, evidence-based medical and surgical therapy for infrainguinal arterial occlusive disease.

Balloon Angioplasty in Tibioperoneal Interventions for Patients With Critical Limb Ischemia

Tibial arterial disease represents the final frontier in the battle against critical limb ischemia (CLI). Isolated infrapopliteal (IP) disease is mainly seen in the elderly (>80 years old), diabetic, and dialysis-dependent patients with CLI. With the development and evolution of catheter-based technology, endovascular therapy (mainly balloon angioplasty) has become the method of choice for revascularization in these patients. The most common challenges are the severely calcified lesion recalcitrant to dilation (as calcium is heterogeneously distributed in the arterial wall) and the long tibial chronic total occlusions. Percutaneous transluminal angioplasty achieves a technically successful result (<30% residual stenosis) in most cases, but it is limited by high restenosis rates. Although several devices have been used in the IP arena (including orbital and directional atherectomy, laser atherectomy, "contact" atherectomy [CROSSER, Bard], and re-entry devices), percutaneous transluminal angioplasty with plain old balloons has been the subject of most studies with several modified iterations, that is, cryoplasty, cutting balloons, focal force balloons, nitinol-"cage"-constrained balloons, tapered balloons, and most recently drug-coated balloons. In this article, we share our current approach to endovascular IP endovascular interventions. We cover the spectrum from pathophysiology, clinical indications, equipment choices, and procedural steps used in our laboratory when treating patients with CLI (which is synonymous with complex anatomy). Regarding what represents the "gold standard" for the treatment of IP disease, a definite answer is currently not available, as multiple studies looking at new generation drug-coated balloons used alone or in combination with different forms of atherectomy are currently under way. We anxiously wait for these results and in the meantime continue to design newer approaches.

Acute pulmonary embolus: the next frontier in venous thromboembolic interventions.

Submassive pulmonary embolism (PE) represents a patient population that is under-recognized and under-treated. Recent clinical trials demonstrated the hemodynamic benefit of IV thrombolytic therapy among these patients; however, it came at the cost of a significantly increased risk of major, particularly intracranial, hemorrhage. Catheter-based treatment modalities have garnered considerable clinical interest in recent years. In particular, ultrasound accelerated thrombolysis, a catheter-based technology that enhances the process of thrombolytic delivery into the thrombus, has emerged as a treatment modality with an increasing number of single-center studies, as well as randomized, controlled clinical trials. Results from these experiences are consistent in achieving outcomes of thrombus resolution and hemodynamic recovery with a low dose thrombolytic infusion protocol, but without the high risk of bleeding complications associated with IV thrombolysis. The clinical data will hopefully be impactful to the development of the next edition of the treatment guidelines, in support of overall recommendations for catheter-based interventions. When available and with appropriate expertise, this modality should be considered as the preferred treatment of both massive and submassive PE.

3-year outcomes of self-expanding Corevalve prosthesis - The Italian Registry.

3-year outcomes of self-expanding Corevalve prosthesis - The Italian Registry.

Infarct Restraint to Limit Adverse Ventricular Remodeling

The left ventricular response to a myocardial infarction is a complex biomechanical process that is only beginning to be understood. Infarct expansion (stretching) is an immediate and progressive phenomenon that is known to initiate and sustain the ventricular dilatation and global loss of contractile function that leads to symptomatic heart failure. Limitation of infarct expansion has, therefore, been identified as a potential therapeutic goal that could reduce the morbidity and cost associated with adverse infarction-induced ventricular remodeling and the symptomatic heart failure that results from it. This review will present experimental work that demonstrates the central importance of infarct expansion to the remodeling process as well as proof-of-concept studies that establish the efficacy of early mechanical infarct restraint for limiting ventricular remodeling after myocardial infarction (MI). Ventricular restraint with polymeric mesh materials (wraps) placed early after MI will be discussed. Data supporting the use of injected acellular biomaterials to alter infarct material properties (stiffness) and geometry (thickness) will also be presented. This approach has been shown to be effective in our laboratory and others in limiting post-infarction remodeling and represents a potential means for limiting infarct expansion early after MI via minimally invasive catheter-based technology.