Electroanatomical mapping after cardiac radioablation for treatment of incessant electrical storm: a case report from the RAVENTA trial.

BACKGROUND: Electroanatomical mapping (EAM)-guided stereotactic arrhythmia radioablation (STAR) is a novel noninvasive therapy option for patients with monomorphic ventricular tachycardia (VT) refractory to antiarrhythmic drugs and/or urgent catheter ablation (CA). Data on success rates in an emergency situation such as electrical storm (ES) are rare. We present a case of a patient with an initially very poor life expectancy after extensive myocardial infarction with therapy-resistant ES, not amendable for further antiarrhythmic drug therapy, implantable cardioverter-defibrillator implantation, or repeated CA who was introduced to the radiation oncology department for emergency STAR as a bail-out therapy. METHODS: Target volume definition and transfer from EAM to CT were validated and quality assured with a semi-automatic, dedicated visualization tool (CARDIO-RT). Emergency STAR was performed with 25 Gy in the framework of the RAVENTA study. The VT burden gradually decreased after STAR; however, a second VT morphology occurred, which was successfully treated with EAM-guided CA 12 days after STAR. RESULTS: The second EAM-guided CA showed areas of low voltage in the irradiated segments, indicating a precise targeting and early functional response to STAR. The patient remained free of any VT recurrence or any radiation-related toxicities and in good general condition during the recent follow-up of 18 months. CONCLUSION: The case highlights the possible approach, caveats, difficulties, and prognosis of a patient severely affected by therapy-resistant VT in whom CA could not lead to VT suppression. Further studies of putative mechanisms of STAR in the acute and chronic phase of this novel therapy are warranted.

Quality assurance process within the RAdiosurgery for VENtricular TAchycardia (RAVENTA) trial for the fusion of electroanatomical mapping and radiotherapy planning imaging data in cardiac radioablation.

A novel quality assurance process for electroanatomical mapping (EAM)-to-radiotherapy planning imaging (RTPI) target transport was assessed within the multi-center multi-platform framework of the RAdiosurgery for VENtricular TAchycardia (RAVENTA) trial. A stand-alone software (CARDIO-RT) was developed to enable platform independent registration of EAM and RTPI of the left ventricle (LV), based on pre-generated radiotherapy contours (RTC). LV-RTC were automatically segmented into the American-Heart-Association 17-segment-model and a manual 3D-3D method based on EAM 3D-geometry data and a semi-automated 2D-3D method based on EAM screenshot projections were developed. The quality of substrate transfer was evaluated in five clinical cases and the structural analyses showed substantial differences between manual target transfer and target transport using CARDIO-RT.

Effect of Combined Etomidate-Ketamine Anesthesia on Perioperative Electrocardiogram and Postoperative Cognitive Dysfunction of Elderly Patients with Rheumatic Heart Valve Disease Undergoing Heart Valve Replacement.

OBJECTIVE: To explore the effect of combined etomidate-ketamine anesthesia on perioperative electrocardiogram (ECG) and postoperative cognitive dysfunction (POCD) of elderly patients with rheumatic heart valve disease (RHVD) undergoing heart valve replacement. METHODS: The data of 100 elderly RHVD patients treated in our hospital from May 2019 to May 2020 were selected for the retrospective analysis, and by adopting the double-blind method, the patients were divided into the ketamine group (n = 50) and the combined group (n = 50) according to the anesthesia methods. During the induction of anesthesia, the patients of the two groups were given a small dose of ketamine (0.5 mg/kg) at 5 µg/kg/min continuously via pump injection until the end of surgery, and on this basis, with the same anesthesia measures, those in the combined group were given etomidate (0.3 mg/kg) additionally. The patients' perioperative ECG indicators, POCD scores, and Numeric Rating Scale (NRS) scores were compared between the two groups. RESULTS: Compared with the ketamine group, the combined group presented significantly lower incidence of ST-T wave changes after anesthesia induction and at the time of intubation and skin incision (P < 0.05), significantly lower average magnitude of ST-segment depression after anesthesia induction (P < 0.001), significantly lower average magnitude of ST-segment elevation after anesthesia induction and extubation (P < 0.001), significantly lower POCD incidence (6.%, P < 0.05), and significantly better NRS score after surgery (P < 0.001). CONCLUSION: Combined etomidate-ketamine anesthesia can stabilize the perioperative ECG indicators of elderly RHVD patients undergoing heart valve replacement, improve their postoperative cognitive function, and reduce their pain sensation, which should be promoted and applied in practice.

Study on friction behavior at the interface between prosthetic socket and liner.

PURPOSE: The friction characteristics at the interface between prosthetic socket and liner have an important influence on the walking function and wearing comfort of amputees. The frictional behavior at the prosthetic socket/liner interface can provide theoretical guidance for the design and selection of prosthetic materials. So it is of great significance to study the friction behavior at prosthetic socket/liner interface. METHODS: The surface roughnesses of the prosthetic socket and liner materials were measured by a laser confocal microscope. The frictional behavior at the prosthetic socket/liner interface was studied on a UMT TriboLab Tribometer by simulating the reciprocating sliding contact mode. An infrared camera was used to take thermal images and then calculated the temperature increase at the socket/liner interface. RESULTS: The coefficient of friction of the silicon rubber fabric are significantly smaller than that of the foam liner materials. The frictional energy dissipation at the liner/acrylic socket interface is the smallest, while it is greater for 3D-printed socket materials. Meanwhile, the temperature increase has a positive correlation to the coefficient of friction and frictional energy dissipation. CONCLUSIONS: The three kinds of 3D-printed materials with high surface roughness have higher interface coefficient of friction and energy dissipation than acrylic material. The stiffness and energy consumption play an important role in the interface friction characteristics of the prosthetic liner materials. The appropriate coefficient of friction at the surface between prosthetic socket and liner is essential. A type of the reinforcement fiber has influence on the friction behavior of the 3D-printed reinforced nylon.