Biventricular assistance with 2 hm3 in a small chest patient: extra-pericardial implant.

We describe the clinical course and treatment of a 53-year-old female, with small chest dimensions, referred to our institution for a primary cardiogenic shock. The patient underwent an on-pump left ventricular assist-device (VAD) implantation with the aid of immediate post-operative paracorporeal right-VAD assistance for an acute right ventricular failure. After two unsuccessful weaning attempts, she underwent extrapericardial HM 3 RVAD implantation.

The Reducer device in patients with angina pectoris: mechanisms, indications, and perspectives.

Despite available pharmacological and interventional therapies, refractory angina is a common and disabling clinical condition, and a major public health problem, which affects patients' quality-of-life, and has a significant impact upon health care resources. Persistent angina is common not only in patients who are not good candidates for revascularization, but also in patients following successful revascularization. Clearly, there is a need for additional treatment options for refractory angina beyond currently available pharmacological and interventional therapies. It is of pivotal importance, in this condition, to practice a patient-centred health assessment approach, measuring success of a new therapy by its effects on patients' symptoms, functional status, and quality-of-life, rather than hard clinical endpoints as used in clinical studies. The coronary sinus Reducer is a novel technology designed to reduce disabling symptoms and improve quality-of-life of patients suffering from refractory angina. This review serves to update the clinician as to current evidence and future perspectives of the optimal utilization of this innovative technology.

Defibrillator-Heart Pump: An Implantable Ventricular Assist Device With Integrated Defibrillator Component-The First In Vitro Testing.

Left ventricular assist devices (LVADs) are an important therapeutic option for patients with end-stage heart failure waiting for heart transplantation or in older patients as definite therapy for heart failure. Interestingly, about 62% of patients receiving LVADs do not have an automatic implantable cardioverter-defibrillator (AICD) at the time of implantation, although these patients have increased risk of being confronted with dangerous arrhythmia. Therefore, an LVAD system including AICD function is a reasonable alternative for such heart failure patients thereby avoiding a second surgical intervention for AICD implantation. In this article, a newly developed system including LVAD and AICD function is introduced, and we also report its first in vitro testing.

[Modern polyurethanes in cardiovascular surgery]. / Sovremennye poliuretany v serdechno-sosudistoi khirurgii.

Currently, there is great clinical demand for synthetic tissue-engineered cardiovascular prostheses with good long-term patency. Polyurethanes belong to the class of polymers with excellent bio- and hemocompatibility. They are known to possess good mechanical properties, but are prone to processes of degradation in conditions of functioning in living organisms. Attempts at solving this problem have resulted in the development of various new subclasses of polyurethanes such as thermoplastic polyether polyurethanes, polyurethanes with a silicone segment, polycarbonate polyurethanes and nanocomposite polyurethanes. This was accompanied and followed by offering a series of new technologies of production of implantable medical devices such as vascular grafts, heart valves and others. In the presented review, we discuss biological and mechanical properties of modern subclasses of polyurethanes, as well as modern methods of manufacturing implantable medical devices made of polyurethanes, especially small-diameter vascular prostheses.

Adoption Decisions for Medical Devices in the Field of Cardiology: Results from a European Survey.

Decisions to adopt medical devices at the hospital level have consequences for health technology assessment (HTA) on system level and are therefore important to decision makers. Our aim was to investigate the characteristics of organizations and individuals that are more inclined to adopt and utilize cardiovascular devices based on a comprehensive analysis of environmental, organizational, individual, and technological factors and to identify corresponding implications for HTA. Seven random intercept hurdle models were estimated using the data obtained from 1249 surveys completed by members of the European Society of Cardiology. The major findings were that better manufacturer support increased the adoption probability of 'new' devices (i.e. in terms of CE mark approval dates), and that budget pressure increased the adoption probability of 'old' devices. Based on our findings, we suggest investigating the role of manufacturer support in more detail to identify diffusion patterns relevant to HTA on system level, to verify whether it functions as a substitute for medical evidence of new devices, and to receive new insights about its relationship with clinical effectiveness and cost-effectiveness. © 2017 The Authors. Health Economics published by John Wiley & Sons, Ltd.

[IMAGING SUPPORT SYSTEMS FOR CARDIOVASCULAR SURGERY].

Because of its low invasiveness, endovascular aneurysmal repair was established as a new method of treatment for aortic aneurysms, revolutionizing the treatment of this condition. With the continuing development of technology and devices, endovascular aneurysmal repair has become safer than before. Innovations in imaging support systems including navigation systems have contributed greatly to the development of endovascular procedures, making transcatheter aortic valve implantation a safe surgical option. We discuss such innovations and the future development of imaging support systems for safe cardiovascular surgery.

Medical Devices; Cardiovascular Devices; Classification of the Apical Closure Device. Final order.

The Food and Drug Administration (FDA) is classifying the apical closure device into class II (special controls). The special controls that will apply to the device are identified in this order and will be part of the codified language for the apical closure device's classification. The Agency is classifying the device into class II (special controls) in order to provide a reasonable assurance of safety and effectiveness of the device.

Subclavian steal syndrome.

"Subclavian steal" refers to a syndrome of symptoms relating to arterial insufficiency in a branch of the subclavian artery stemming from flow reversal,attributable to occlusive disease in the subclavian artery proximal to that branch that is usually atheroscleroticin cause. Most patients are asymptomatic,but patients with IMA bypass grafts may manifest angina elicited by exercise of the upper extremity ipsilateral to the graft and stenosis (so called"coronary-subclavian steal").Subclavian steal may also manifest as vertebrobasilar insufficiency or,most commonly, arm claudication.Subclavian steal should be considered among patients exhibiting suggestive symptoms. A meticulous examination of segmental pulses and pressures,as well as judicious use of duplex ultrasonography, magnetic resonance angiography, computed tomography angiography, or conventional angiography can confirm the presence of subclavian stenosis. Symptomatic patients benefit from either percutaneousor surgical revascularization,depending on both anatomic and patient factors. Subclavian stenosis,regardless of symptoms, is a marker of atherosclerotic disease and increased risk for cardiovascular and cerebrovascular events.

Sensor-Based Electromagnetic Navigation (Mediguide®): How Accurate Is It? A Phantom Model Study.

BACKGROUND: Data about localization reproducibility as well as spatial and visual accuracy of the new MediGuide® sensor-based electroanatomic navigation technology are scarce. We therefore sought to quantify these parameters based on phantom experiments. METHODS AND RESULTS: A realistic heart phantom was generated in a 3D-Printer. A CT scan was performed on the phantom. The phantom itself served as ground-truth reference to ensure exact and reproducible catheter placement. A MediGuide® catheter was repeatedly tagged at selected positions to assess accuracy of point localization. The catheter was also used to acquire a MediGuide®-scaled geometry in the EnSite Velocity® electroanatomic mapping system. The acquired geometries (MediGuide®-scaled and EnSite Velocity®-scaled) were compared to a CT segmentation of the phantom to quantify concordance. Distances between landmarks were measured in the EnSite Velocity®- and MediGuide®-scaled geometry and the CT dataset for Bland-Altman comparison. The visualization of virtual MediGuide® catheter tips was compared to their corresponding representation on fluoroscopic cine-loops. Point localization accuracy was 0.5 ± 0.3 mm for MediGuide® and 1.4 ± 0.7 mm for EnSite Velocity®. The 3D accuracy of the geometries was 1.1 ± 1.4 mm (MediGuide®-scaled) and 3.2 ± 1.6 mm (not MediGuide®-scaled). The offset between virtual MediGuide® catheter visualization and catheter representation on corresponding fluoroscopic cine-loops was 0.4 ± 0.1 mm. CONCLUSIONS: The MediGuide® system shows a very high level of accuracy regarding localization reproducibility as well as spatial and visual accuracy, which can be ascribed to the magnetic field localization technology. The observed offsets between the geometry visualization and the real phantom are below a clinically relevant threshold.

An overview of left atrial appendage occlusion devices.

Atrial fibrillation (AF) places patients at increased risk of thromboembolic events that can be devastating. The left atrial appendage (LAA) has been identified as the source of thrombus formation in nonvalvular AF. Traditionally, systemic anticoagulation has been used to reduce the risk of stroke and systemic embolism. However, anticoagulation is not well tolerated in all patients and is underutilized. As a potential alternative to anticoagulation, novel therapies have been developed to remove the LAA. Three main techniques are being utilized to accomplish LAA exclusion: percutaneous intracardiac, percutaneous epicardial, and surgical approaches. Emerging evidence suggests that LAA exclusion may be an effective means of reducing the risk of stroke in patients with nonvalvular AF.

Iron and iron-based alloys for temporary cardiovascular applications.

In the last decade, biodegradable metals have emerged as a topic of interest for particular biomedical applications which require high strength to bulk ratio, including for cardiovascular stents. The advantages of biodegradable materials are related to the reduction of long term risks associated with the presence of permanent metal implants, e.g. chronic inflammation and in-stent restenosis. From a structural point of view, the analysis of the literature reveals that iron-based alloys used as temporary biodegradable stents have several advantages over Mg-based alloys in terms of ductility and strength. Efforts on the modification and tunability of iron-based alloys design and compositions have been mainly focused on controlling the degradation rate while retaining the mechanical integrity within a reasonable period. The early pre-clinical results of many iron-based alloys seem promising for future implants developments. This review discusses the available literature focusing mainly on: (i) Fe and Fe-based alloys design and fabrication techniques; (ii) in vitro and in vivo performance; (iii) cytotoxicity and cell viability tests.

Correction of Adult Scimitar Syndrome Using a Lateral Endoscopic Approach with Robotics.

We present two adult patients in whom anatomic correction of scimitar syndrome (SS) was accomplished by redirecting the anomalous pulmonary venous drainage into the left atrium using a reinforced polytetrafluoroethylene (PTFE) graft extension. A right lateral endoscopic approach with robotic instrumentation (LEAR) was utilized with excellent early and long-term results.

The evaluation of steerable ultrasonic catheters for minimally invasive MRI-guided cardiac ablation.

PURPOSE: The purpose of this study was to develop steerable MR-compatible ultrasound catheters suitable for minimally invasive MRI-guided cardiac ablation therapies. METHODS: MRI-compatible ultrasound steerable catheters were developed and tested for their overall tissue heating performance and safety. Ultrasound transducers were mounted on a monodirectional deflectable catheter tip that was made to be MRI-compatible. Catheter safety was assessed on the potential to form hot spots at the distal end of the catheter throughout fast spin echo and thermometry scans. Heating experiments were performed on phantoms and ex vivo porcine cardiac samples. RESULTS: During catheter safety experiments, a maximum temperature increase of 11.35 ± 0.83°C was evident after a 12-min, 40-s fast spin echo scan with a whole body specific absorption rate (SAR) of 1.9 W/kg and 1.07 ± 0.22°C during thermometry scans (flip angle = 90°; scan time = 12 min, 41 s; whole body SAR = 0.34 W/kg). Temperature elevations induced by the sonication were shown to be on the order of 38.1 ± 5.2°C for phantom experiments and 49.3 ± 9.7°C for ex vivo cardiac samples. CONCLUSION: Steerable ultrasound catheters have the potential to be safely placed in an MR system with little concern of catheter self-heating and driven to heat surrounding structures to cause ablations. In addition, these catheters have the added benefit of a deflectable tip that allows the treatment of multiple targets from within the bore of the MR scanner.

A 1.5T MRI-conditional 12-lead electrocardiogram for MRI and intra-MR intervention.

PURPOSE: High-fidelity 12-lead electrocardiogram (ECG) is important for physiological monitoring of patients during MR-guided intervention and cardiac MRI. Issues in obtaining noncorrupted ECGs inside MRI include a superimposed magneto-hydro-dynamic voltage, gradient switching-induced voltages, and radiofrequency heating. These problems increase with magnetic field. The aim of this study is to develop and clinically validate a 1.5T MRI-conditional 12-lead ECG system. METHODS: The system was constructed with transmission lines to reduce radiofrequency induction and switching circuits to remove induced voltages. Adaptive filters, trained by 12-lead measurements outside MRI and in two orientations inside MRI, were used to remove the magneto-hydro-dynamic voltage. The system was tested on 10 (one exercising) volunteers and four arrhythmia patients. RESULTS: Switching circuits removed most imaging-induced voltages (residual noise <3% of the R-wave). Magneto-hydro-dynamic voltage removal provided intra-MRI ECGs that varied by <3.8% from those outside the MRI, preserving the true S-wave to T-wave segment. In premature ventricular contraction (PVC) patients, clean ECGs separated premature ventricular contraction and sinus rhythm beats. Measured heating was <1.5°C. The system reliably acquired multiphase (steady-state free precession) wall-motion-cine and phase-contrast-cine scans, including subjects in whom 4-lead gating failed. The system required a minimum repetition time of 4 ms to allow robust ECG processing. CONCLUSION: High-fidelity intra-MRI 12-lead ECG is possible.

Open-irrigated laser catheter ablation: relationship between the level of energy, myocardial thickness, and collateral damages in a dog model.

AIMS: To evaluate laser lesion formation in the beating hearts of dogs by using an open-irrigated electrode-laser mapping and ablation heart catheter. METHODS AND RESULTS: A total of 50 laser applications at 15 W (n = 31) and 20 W (n = 19) for 10-50 s, with an irrigation flow of 35 mL/min were aimed at the right (n = 15) and left (n = 9) atrial, right (n = 15) and left (n = 11) ventricular walls in five dogs (6-16/dog), by using an open-irrigated laser ablation catheter. The 1064 nm diode laser was provided with a light control system, a Flowmeter, and a transoesophageal laser sensor. Lesions were measured and were evaluated morphometrically. Transmural lesions were achieved in seconds regardless of the level of energy applied. Laser applications at 15 W > 10 s aimed at the atrial walls produced collateral lesions to the lung or to the oesophagus. Laser applications at 20 W > 30 s aimed at the ventricular walls may result in steam pop with intramural cavitations and arrhythmias. Collateral damages to the oesophagus occurred only when the transoesophageal light sensor was deactivated. CONCLUSION: To avoid unwanted effects during laser catheter ablation by using an open-irrigated laser catheter energy delivery must be adapted to the thickness of the myocardial wall. Light control system and a transoesophageal light sensor may help reduce the risks of myocardial and collateral damages.

[da Vinci surgical system].

The da Vinci surgical system was developed by Intuitive Surgical Inc. in the United States as an endoscopic surgical device to assist remote control surgeries. In 1998, the Da Vinci system was first used for cardiothoracic procedures. Currently a combination of robot-assisted internal thoracic artery harvest together with coronary artery bypass grafting (CABG) through a mini-incision (ThoraCAB) or totally endoscopic procedures including anastomoses under robotic assistance (TECAB) are being conducted for the treatment of coronary artery diseases. With the recent advances in catheter interventions, hybrid procedures combining catheter intervention with ThoraCAB or TECAB are anticipated in the future.On the other hand, with the decrease in number of coronary artery bypass surgeries, the share of valvular surgeries is expected to increase in the future. Among them, mitral valvuloplasty for mitral regurgitation is anticipated to be conducted mainly by low-invasive procedures, represented by minimally invasive cardiac surgery( MICS) and robot-assisted surgery. Apart from the intrinsic good surgical view, robotic-assisted systems offer additional advantages of the availability of an amplified view and the easy to observe the mitral valve in the physiological position. Thus, robotic surgical surgeries that make complicated procedures easier are expected to accomplish further developments in the future. Furthermore, while the number of surgeries for atrial septal defects has decreased dramatically following the widespread use of Amplatzer septal occluder, robotic surgery may become a good indication for cases in which the Amplatzer device is not indicated. In Japan, clinical trial of the da Vinci robotic system for heart surgeries has been completed. Statutory approval of the da Vinci system for mitral regurgitation and atrial septal defects is anticipated in the next few years.

[Effect of polyoxyalkanoate -based cover on properties of suture material].

The results of a surgical intervention and, in particular, reconstructive operations on arteries are largely influenced by suture material. Despite a wide range of choice, the market concerned lacks suture material which would make it possible to decrease the risk of thrombosis in the area of the vascular anastomosis. In order to increase bio- and haemocompatibility, the surface of a polypropylene thread was covered with a layer based on polyoxyalkanoates - polyhydroxybutyrate and copolymer polyhydroxybutyrate-oxyvaleriate (PHBV). The strongest and most uniformly distributed coating of the polypropylene thread was provided by PHBV. We assessed the bio- and haemocompatibility properties of suture material modified by PHBV, revealing that this modification does not exert negative effect on the main components of blood - thrombocytes and erythrocytes. Treatment of the thread's surface with PHBV promoted a significant (p<0.05) decrease in the amount of absorbed proteins in the area of the vascular anastomosis in experiment: the amount of IgM decreased by 26%, that of fibrinogen by 29%, and that of D-Dimer by 281%, being on the whole indicative of bio- and haemocompatibility of the modified suture material.

Assessment of left atrial function after percutaneous closure of patent foramen ovale.

BACKGROUND: The influence of atrial septal occluders in left atrial (LA) function after percutaneous closure of patent foramen ovale (PFO) has not been thoroughly studied. METHODS: Twenty-five patients (mean age 40.7 ± 12 years) undergoing percutaneous PFO closure were enrolled in this study. Transthoracic echocardiogram (TTE) was performed 3 and 6 months before the procedure. Volumetric indices (active emptying fraction: LA AEF, expansion index: LA EI, and passive emptying fraction: LA PEF), strain and strain rate (SR), were calculated during the contractile, reservoir, and conduit LA phases for the lateral, anterior, and inferior LA walls with TTE. RESULTS: After 3 months, a decrease in the SR of the LA anterior wall was observed (from 2.12 ± 0.22 to 1.66 ± 0.26, P < 0.045), while the LA lateral wall strain was found to be increased (from 0.708 ± 0.15 to 0.783 ± 0.159, P < 0.001). Moreover, simultaneously LA AEF was greater compared with baseline (from 31.0 ± 1.6 to 34.0 ± 1.6, P < 0.004). However, all these alterations reversed at 6 months. CONCLUSIONS: Segmental LA function is altered transiently after percutaneous PFO closure with a septal occlude. The LA anterior wall SR decreases, while the lateral wall strain increases. The impact of these alterations needs further clarification.

Microbubble transmission during cardiotomy infusion of a hardshell venous reservoir with integrated cardiotomy versus a softshell venous reservoir with separated cardiotomy: an in vitro comparison.

An important mechanism for postoperative cognitive impairment after cardiac surgery using cardiopulmonary bypass (CPB) is microemboli. One component of the CPB circuit-the cardiotomy-is a major source of gaseous microemboli because it aspirates significant volumes of air with blood from the operative field and intracardiac chambers. Cardiotomies are either integrated within an open hardshell venous reservoir (IC-HSVR) or are a separate canister attached to a softshell collapsible venous reservoir bag (SC-SSVR). The purpose of this study was to compare the Medtronic IC-HSVR (Affinity NT CVR) with Medtronic's SC-SSVR (CB 1351, CBMVR 1600) in terms of relative microbubble transmission during cardiotomy infusion. A recirculating in vitro circuit primed with blood was used to compare the two cardiotomy-reservoir systems with the venous reservoir in the SC-SSVR further assessed in a fully closed or partially open state (SC-SSVR-closed; SC-SSVR-open). Microbubbles were detected using a GAMPT BC100 Doppler system in the outflow line of the venous reservoir. Measurements were taken before (baseline) and after aerated prime was pumped into the cardiotomy while altering pump flow rates (3 L/min; 5 L/min) and reservoir prime volumes (400 mL; 900 mL). Infusing cardiotomy blood into the venous reservoir was associated with an increase in microbubbles and bubble volume transmitted by both cardiotomy-reservoir systems with the magnitude rising with reduced prime volumes. The effect was markedly greater with the IC-HSVR. The IC-HSVR also transmitted larger bubbles, particularly with reduced prime volumes. There was no significant difference in microbubble transmission seen between the SC-SSVR-closed and SC-SSVR-open. The SC-SSVR transmits fewer microbubbles than the IC-HSVR during cardiotomy infusion and should be considered as the preferential system. Because both cardiotomy-reservoir systems transmitted microbubbles during cardiotomy infusion, particularly at the lower venous reservoir volume, it is important to use strategies to minimize cardiotomy microbubble infusion.