Showing papers by "Volkmar Falk published in 2023"

Clinical quantitative coronary artery stenosis and coronary atherosclerosis imaging: a Consensus Statement from the Quantitative Cardiovascular Imaging Study Group.

Abstract: The detection and characterization of coronary artery stenosis and atherosclerosis using imaging tools are key for clinical decision-making in patients with known or suspected coronary artery disease. In this regard, imaging-based quantification can be improved by choosing the most appropriate imaging modality for diagnosis, treatment and procedural planning. In this Consensus Statement, we provide clinical consensus recommendations on the optimal use of different imaging techniques in various patient populations and describe the advances in imaging technology. Clinical consensus recommendations on the appropriateness of each imaging technique for direct coronary artery visualization were derived through a three-step, real-time Delphi process that took place before, during and after the Second International Quantitative Cardiovascular Imaging Meeting in September 2022. According to the Delphi survey answers, CT is the method of choice to rule out obstructive stenosis in patients with an intermediate pre-test probability of coronary artery disease and enables quantitative assessment of coronary plaque with respect to dimensions, composition, location and related risk of future cardiovascular events, whereas MRI facilitates the visualization of coronary plaque and can be used in experienced centres as a radiation-free, second-line option for non-invasive coronary angiography. PET has the greatest potential for quantifying inflammation in coronary plaque but SPECT currently has a limited role in clinical coronary artery stenosis and atherosclerosis imaging. Invasive coronary angiography is the reference standard for stenosis assessment but cannot characterize coronary plaques. Finally, intravascular ultrasonography and optical coherence tomography are the most important invasive imaging modalities for the identification of plaques at high risk of rupture. The recommendations made in this Consensus Statement will help clinicians to choose the most appropriate imaging modality on the basis of the specific clinical scenario, individual patient characteristics and the availability of each imaging modality. In this Consensus Statement, Dewey and the other members of the Quantitative Cardiovascular Imaging Study Group provide clinical consensus recommendations on the optimal use of different imaging techniques in various patient populations to detect and assess coronary artery stenosis and atherosclerosis.

Subannular repair in secondary mitral regurgitation with restricted leaflet motion during systole

Abstract: Objective Ventricular secondary mitral regurgitation (SMR) (Carpentier type IIIb) results from left ventricular (LV) remodelling, displacement of papillary muscles and tethering of mitral leaflets. The most appropriate treatment approach remains controversial. We aimed to assess the safety and efficacy of standardised relocation of both papillary muscles (subannular repair) at 1-year follow-up (FU). Methods REFORM-MR (Reform-Mitral Regurgitation) is a prospective, multicentre registry that enrolled consecutive patients with ventricular SMR (Carpentier type IIIb) undergoing standardised subannular mitral valve (MV) repair in combination with annuloplasty at five sites in Germany. Here, we report survival, freedom from recurrence of MR >2+, freedom from major adverse cardiac and cerebrovascular events (MACCEs), including cardiovascular death, myocardial infarction, stroke, MV reintervention and echocardiographic parameters of residual leaflet tethering at 1-year FU. Results A total of 94 patients (69.1% male) with a mean age of 65.1±9.7 years met the inclusion criteria. Advanced LV dysfunction (mean left ventricular ejection fraction 36.4±10.5%) and severe LV dilatation (mean left ventricular end-diastolic diameter 61.0±9.3 mm) resulted in severe mitral leaflet tethering (mean tenting height 10.6±3.0 mm) and an elevated mean EURO Score II of 4.8±4.6 prior to surgery. Subannular repair was successfully performed in all patients, without operative mortality or complications. One-year survival was 95.5%. At 12 months, a durable reduction of mitral leaflet tethering resulted in a low rate (4.2%) of recurrent MR >2+. In addition to a significant improvement in New York Heart Association (NYHA) class (22.4% patients in NYHA III/IV vs 64.5% patients at baseline, p<0.001), freedom from MACCE was observed in 91.1% of patients. Conclusions Our study demonstrates the safety and feasibility of standardised subannular repair to treat ventricular SMR (Carpentier type IIIb) in a multicentre setting. By addressing mitral leaflet tethering, papillary muscle relocation results in very satisfactory 1-year outcomes and has the potential to durably restore MV geometry; nevertheless, long-term FU is mandatory. Trial registration number NCT03470155.

Initial results of a prospective, multicenter study on the use of a biosynthesized cellulose membrane as a separation in de novo CIED implantations

Abstract: Abstract Funding Acknowledgements Type of funding sources: Other. Main funding source(s): Public Grant: EIC Accelerator pilot –SME Instrument (H2020-EIC-SMEInst-2018-2020) Private Company: Hylomorph AG Background Fibrosis is the result of foreign body reaction against the hardware of cardiac implantable electronic devices (CIEDs). Generator pocket fibrotic adhesions increase the complexity and risks of CIED revision surgeries. There is limited evidence that synthetic or ex vivo resorbable envelopes can prevent or reduce fibrosis. Objective We conducted a multicenter, prospective, single-arm, interventional study of microengineered biosynthesized cellulose (BC) as separation layer for CIED pockets. Patients who were undergoing a CIED de novo implantation were included to receive the protective device. The primary end point was the maintenance of a detectable barrier between the CIED generator and the surrounding tissue at 12 months. The secondary end point for safety was procedure-related or system-related complications within 12 months. Methods High resolution ultrasound (HRUS) imaging of the protective layer, the CIED and the surrounding tissue of the generator pocket were collected at the day of implant, and at one, six-, and twelve-months follow-up visits in 35 patients (of 46 recruited). The images were individually processed and analyzed. Results HRUS imaging allowed the reproducible detection of (1) the CIED interface as fiducial reference marker, (2) the densification of the surrounding tissue and (3) the segregation between the two. A detectable separation between the CIED and the surrounding tissue was identified in all patients at all follow-up visits demonstrating the enforcement of a durable and stable barrier. The evolution of HRUS signal intensity indicated a time-dependent densification compatible with the buildup of fibrotic tissue around the generator. The thickness of this tissue was measured rendering values below 1 mm. Mean time for cellulose membrane application was 7.5±4 minutes. Investigational device related major complications were 0%. Conclusion Adjunctive use of an antifibrotic device established a durable separation between the CIED and the surrounding soft tissue in the generator pocket without a significantly higher incidence of complications or a relevantly increased procedural time. HRUS imaging indicated a limited buildup of denser tissue around the generator and no adhesions inside the cellulose membrane. Altogether these results suggest that BC may be beneficial for post-implantation pocket health as an alternative to envelopes of synthetic or animal origin and may enable easy pocket access in revision procedures.

Impact of preoperative mitral regurgitation on LVAD patients: propensity-score matched analysis of the EUROMACS dataset.

Abstract: INTRODUCTION Mitral regurgitation (MR) is frequently observed in patients undergoing left ventricular assist device (LVAD) implantation. We investigated the impact of preoperative MR on LVAD patients. METHODS A retrospective propensity score-matched analysis of adult patients enrolled in the EUROMACS registry between 01/01/2011 and 30/11/2021 was performed. Patients were divided into two groups according to the grade of preoperative MR: none-to-mild (MR 0-II) or moderate-to-severe (MR III-IV). RESULTS Following 1:1 propensity score matching, each group consisted of 914 patients. Incidence of postoperative temporary right ventricular support, reoperation for bleeding, and dialysis was similar. MR III-IV demonstrated shorter median ICU stay (14 d [6; 27.8] vs 10 d [5; 22], p = 0.004) and ventilation time (72 h [22, 320] vs 31 h [18, 150], p < 0.001).Mortality was lower for MR III-IV patients (SHR 0.66, 95% CI: 0.59-0.73, p < 0.001). The 1-year survival was 68.1% (95% CI: 65.1-71.3%) in MR 0-II and 75% (95% CI: 72.1-78%) in MR III-IV. A lower incidence of total complications (OR 0.93 [0.89-0.98], p = 0.003) and trend towards a lower risk of neurological dysfunction (SHR 0.79; 95% CI: 0.61-1.01, p = 0.063) and sustained ventricular tachycardia (OR 0.93 [0.54-1.03], p = 0.074) were demonstrated for MR III-IV. The risk of fatal stroke and pump thrombosis was similar. CONCLUSION Moderate-to-severe MR in patients undergoing LVAD implantation is associated with better mid-term survival and lower incidence of total major adverse events and complications. The incidence of severe postoperative complications including fatal stroke and device thrombosis was similar.

Severe pulmonary valve insufficiency caused by transjugular cannulation of pulmonary artery for right ventricular assist device: diagnosis and surgical solution—a case report

Abstract: Abstract Implantation of a temporary percutaneous right ventricular assist device (RVAD) in patients with right heart failure after left ventricular assist device (LVAD) implantation is an established technique that may cause complications. We present a 60-year-old male patient who underwent urgent LVAD implantation. On the second postoperative day the patient developed acute right heart failure. We implanted a temporary percutaneous RVAD with two cannulas via the right internal jugular vein and the right femoral vein. Transesophageal echocardiography revealed severe pulmonary insufficiency. After performing re-sternotomy we anastomosed a prosthetic graft to the pulmonary trunk (PT), performed subxiphoid tunneling of the graft and replaced the transjugular outflow cannula. The pulmonary regurgitation caused by the percutaneous transvalvular cannula disappeared. In such case a direct anastomosis to the PT is the solution.

In-vitro investigation of endothelial monolayer retention on an inflow VAD cannula inside a beating heart phantom.

Abstract: Ventricular assist devices (VADs) provide an alternative solution to heart transplantation for patients with end-stage heart failure. Insufficient hemocompatibility of VAD components can result in severe adverse events, such as thromboembolic stroke, and readmissions. To enhance VAD hemocompatibility, and avoid thrombus formation, surface modification techniques and endothelialization strategies are employed. In this work, a free form patterning topography is selected to facilitate the endothelialization of the outer surface of the inflow cannula (IC) of a commercial VAD. An endothelialization protocol for convoluted surfaces such as the IC is produced, and the retainment of the endothelial cell (EC) monolayer is evaluated. To allow this evaluation, a dedicated experimental setup is developed to simulate realistic flow phenomena inside an artificial, beating heart phantom with a VAD implanted on its apex. The procedural steps of mounting the system result to the impairment of the EC monolayer, which is further compromised by the developed flow and pressure conditions, as well as by the contact with the moving inner structures of the heart phantom. Importantly, the EC monolayer is better maintained in the lower part of the IC, which is more susceptible to thrombus formation and may therefore aid in minimizing the hemocompatibility related adverse events after the VAD implantation.

Image-based ring size prediction for mitral valve repair.

Abstract: OBJECTIVES Annuloplasty rings are routinely used in mitral valve repair (MVr). However, accurate annuloplasty ring size selection is essential to obtain a favorable outcome. Moreover, ring sizing can be challenging in some patients and is highly influenced by surgeons' experience. This study investigated the utility of three-dimensional mitral valve (3D-MV) reconstruction models to predict annuloplasty ring size for MVr. METHODS A total of 150 patients undergoing minimally invasive MVr with annuloplasty ring due to Carpentier type II pathology and who were discharged with none/trace residual MR were included. 3D-MV reconstruction models were created with a semi-automated software package (4D MV Analysis; Tomtec Imaging Systems, Munich, Germany) to quantitate MV geometry. To predict the ring size, univariable and multivariable linear regression analyses were performed. RESULTS Between 3D-MV reconstruction values and implanted ring sizes, the highest correlation coefficients were provided by commissural width (CW) (0.839; p < 0.001), intertrigonal distance (ITD) (0.796; p < 0.001), annulus area (0.782; p < 0.001), anterior mitral leaflet area (0.767; p < 0.001), Anterior-posterior diameter (0.679; p < 0.001) and AML length (0.515; p < 0.001). In multivariable regression analysis, only CW and ITD were found to be independent predictors of annuloplasty ring size (R2=0.743; p < 0.001). The highest level of agreement was achieved with CW and ITD, and 76.6% of patients received a ring with no greater than one ring size difference from the predicted ring sizes. CONCLUSIONS 3D-MV reconstruction models can support surgeons in the decision-making process for annuloplasty ring sizing. The present study may be a first step towards accurate annuloplasty ring size prediction using multimodal Machine Learning decision support.

A clinical study to evaluate the safe and effective use of Stethoglove, a single use stethoscope cover to reduce pathogen transmission during auscultation

Abstract: Objectives: Stethoscopes carry a significant risk for pathogen transmission. Here, the safe use and performance of Stethoglove(R), a non-sterile, single-use cover for stethoscopes, that is impermeable for pathogens, was investigated by different healthcare professionals (HCPs) in the postoperative care setting of an intensive care unit (ICU). Methods: Fifty-four patients underwent routine auscultations with the use of Stethoglove(R). The participating HCPs (n=34) rated each auscultation with Stethoglove(R) on a 5-point Likert scale. The mean ratings of acoustic quality and Stethoglove(R) handling were defined as primary and secondary performance endpoint. Results: 534 auscultations with Stethoglove(R) were performed (average 15.7/user) on the lungs (36.1%), the abdomen (33.2%), the heart (28.8%) or other body-sites (1.9%). No adverse device-effects occurred. The acoustic quality was rated at 4.2{+/-}0.7 (mean) with a total of 86.1% of all auscultations being rated at least as 4/5, and with no rating as below 2. The Stethoglove(R) handling was rated at 3.7{+/-}0.8 (mean) with a total of 96.4% of all auscultations being rated at least 3/5. Conclusions: Using a real-world setting, this study demonstrates that Stethoglove(R) can be safely and effectively used as cover for stethoscopes during auscultation. Stethoglove(R) may therefore represent a useful and easy-to-implement tool for preventing stethoscope-mediated infections.

A clinical study to evaluate the safe and effective use of a new, single use stethoscope cover to enable reduction in pathogen transmission during auscultation

Abstract: Objectives Stethoscopes carry a significant risk for pathogen transmission. Here, the safe use and performance of a new, non-sterile, single-use stethoscope cover (SC), that is impermeable for pathogens, was investigated by different healthcare professionals (HCPs) in the postoperative care setting of an intensive care unit (ICU). Methods Fifty-four patients underwent routine auscultations with the use of the SC (Stethoglove®, Stethoglove GmbH, Hamburg, Germany). The participating HCPs (n = 34) rated each auscultation with the SC on a 5-point Likert scale. The mean ratings of acoustic quality and the SC handling were defined as primary and secondary performance endpoint. Results 534 auscultations with the SC were performed (average 15.7/user) on the lungs (36.1%), the abdomen (33.2%), the heart (28.8%), or other body-sites (1.9%). No adverse device-effects occurred. The acoustic quality was rated at 4.2 ± 0.7 (mean) with a total of 86.1% of all auscultations being rated at least as 4/5, and with no rating as below 2. The SC handling was rated at 3.7 ± 0.8 (mean) with a total of 96.4% of all auscultations being rated at least 3/5. Conclusion Using a real-world setting, this study demonstrates that the SC can be safely and effectively used as cover for stethoscopes during auscultation. The SC may therefore represent a useful and easy-to-implement tool for preventing stethoscope-mediated infections. Study Registration: EUDAMED no. CIV-21-09-037762.

Evaluation of an Excimer Laser-Assisted Nonocclusive Anastomotic Connector in Minimally Invasive Coronary Artery Surgery

Abstract: Background: Minimally invasive direct coronary artery bypass surgery (MIDCAB) is still underutilized due to the technical challenges of this procedure. Anastomotic connectors could aid at overcoming these challenges. In this present study, we compared two optimized excimer laser-assisted nonocclusive anastomotic connectors for application in MIDCAB.

Outcomes and survival following thoracic endovascular repair in patients with aortic aneurysms limited to the descending thoracic aorta

Abstract: Thoracic endovascular aortic repair (TEVAR) is a well-established therapy for descending aortic aneurysms (DTA). There is a paucity of large series reporting the mid- and long-term outcomes from this era. The main aim of this study was to evaluate the outcomes of TEVAR with regards to the effect of aortic morphology and procedure-related variables on survival, reintervention and freedom from endoleaks.In this retrospective single center study, we evaluated the clinical outcomes among 158 consecutive patients with DTA than underwent TEVAR between 2006 and 2019 at our center. The cohort included 51% patients with device landing zones proximal to the subclavian artery and 25.9% patients undergoing an emergent or urgent TEVAR. The primary outcome was survival, and secondary outcomes were reintervention and occurrence of endoleaks.Median follow-up was 33 months [IQR 12 to 70] while 50 patients (30.6%) had longer than 5-year follow-up. With a median patient age of 74 years, post-operative Kaplan Meyer survival estimates were 94.3% (95%CI 90.8-98.0, SE 0.018%) at 30 days, 76.4% (95%CI 70.0-83.3, SE 0.034%) at one year and, 52.9% (95%CI 45.0-62.2, SE 0.043%) at five years. Freedom from reintervention at 30 days, one year, and five years was 92.9% (95%CI 89.0-97.1, SE 0.021%), 80.0% (95%CI 72.6-88.1, SE 0.039%), and 52.8% (95%CI 41.4-67.4, SE 0.065%), respectively. On cox regression analysis greater aneurysm diameter, and the use of device landing zones in aortic regions 0-1 were associated with an increased probability of all-cause mortality, and with reintervention during follow-up. Independent of aneurysm size undergoing urgent or emergent TEVAR was associated with higher mortality risk for the first three years post-operative but not on long-term follow-up.Larger aneurysms and those requiring stent-graft landing in aortic zones 0 or 1, are associated with higher risk for mortality and reintervention. There remains a need to optimize clinical management and device design for larger proximal aneurysms.

Tailoring crystallinity for hemocompatible and durable PEEK cardiovascular implants.

Abstract: Polymers have the potential to replace metallic or bioprosthetic heart valve components due to superior durability and inertness while allowing for native tissue-like flexibility. Despite these appealing properties, certain polymers such as polyetheretherketone (PEEK) have issues with hemocompatibility, which have previously been addressed through assorted complex processes. In this paper, we explore the enhancement of PEEK hemocompatibility with polymer crystallinity. Amorphous, semi-crystalline and crystalline PEEK are investigated in addition to a highly crystalline carbon fiber (CF)/PEEK composite material (CFPEEK). The functional group density of the PEEK samples is determined, showing that higher crystallinity results in increased amount of surface carbonyl functional groups. The increase of crystallinity (and negatively charged groups) appears to cause significant reductions in platelet adhesion (33 vs. 1.5 % surface coverage), hemolysis (1.55 vs. 0.75 %∙cm-2), and thrombin generation rate (4840 vs. 1585 mU/mL/min/cm2). In combination with the hemocompatibility study, mechanical characterization demonstrates that tailoring crystallinity is a simple and effective method to control both hemocompatibility and mechanical performance of PEEK. Furthermore, the results display that CFPEEK composite performed very well in all categories due to its enhanced crystallinity and complete carbon encapsulation, allowing the unique properties of CFPEEK to empower new concepts in cardiovascular device design.

Transaxillary implantation of a temporary microaxial left ventricular assist device in a patient with a rectangular kinked subclavian artery.

Abstract: Transaxillary implantation of a temporary microaxial left ventricular assist device in patients suffering from cardiogenic shock is an established technique. We present a 77-year-old female patient with severe mitral regurgitation. She underwent minimally invasive surgical mitral valve replacement. After an uneventful postoperative course, the patient developed acute heart failure on the 11th postoperative day. Transthoracic echocardiography revealed new onset of takotsubo cardiomyopathy with a severely decreased left ventricular ejection fraction. Implantation of a microaxial flow pump for left ventricular decompression was scheduled. Preoperative computed tomography revealed a rectangular course of the right subclavian artery. To advance the Impella we employed an introducer fitted over the guidewire behind the Impella device as a 'cue stick' to move the rigid part of the pump forward to overcome the kinking using a 'shuffleboard technique'. The haemodynamic situation stabilized immediately after implantation. The Impella 5.5 was successfully weaned after six days of support. In the event of (rectangular) kinking of the subclavian artery, the 'shuffleboard technique' can be used for successful positioning of the pump.

The DZHK research platform: maximisation of scientific value by enabling access to health data and biological samples collected in cardiovascular clinical studies

Abstract: The German Centre for Cardiovascular Research (DZHK) is one of the German Centres for Health Research and aims to conduct early and guideline-relevant studies to develop new therapies and diagnostics that impact the lives of people with cardiovascular disease. Therefore, DZHK members designed a collaboratively organised and integrated research platform connecting all sites and partners. The overarching objectives of the research platform are the standardisation of prospective data and biological sample collections among all studies and the development of a sustainable centrally standardised storage in compliance with general legal regulations and the FAIR principles. The main elements of the DZHK infrastructure are web-based and central units for data management, LIMS, IDMS, and transfer office, embedded in a framework consisting of the DZHK Use and Access Policy, and the Ethics and Data Protection Concept. This framework is characterised by a modular design allowing a high standardisation across all studies. For studies that require even tighter criteria additional quality levels are defined. In addition, the Public Open Data strategy is an important focus of DZHK. The DZHK operates as one legal entity holding all rights of data and biological sample usage, according to the DZHK Use and Access Policy. All DZHK studies collect a basic set of data and biosamples, accompanied by specific clinical and imaging data and biobanking. The DZHK infrastructure was constructed by scientists with the focus on the needs of scientists conducting clinical studies. Through this, the DZHK enables the interdisciplinary and multiple use of data and biological samples by scientists inside and outside the DZHK. So far, 27 DZHK studies recruited well over 11,200 participants suffering from major cardiovascular disorders such as myocardial infarction or heart failure. Currently, data and samples of five DZHK studies of the DZHK Heart Bank can be applied for.

Minimally Invasive Extirpation of Benign Atrial Cardiac Tumors: Clinical Follow-Up and Survival

Abstract: Objective: Evidence determining the optimal treatment for cardiac tumors is rare. We report our midterm clinical outcome and patient characteristics of our series undergoing atrial tumor removal through a right lateral minithoracotomy (RLMT). Methods: From 2015 to 2021, 51 patients underwent RLMT for atrial tumor extirpation. Patients receiving concomitant atrioventricular valvular, cryoablation, and/or patent foramen ovale closure surgery were included. Follow-up was performed using standardized questionnaires (mean: 1,041 ± 666 days). Follow-up involved any tumor recurrence, clinical symptoms, and any recurrent arterial embolization. Survival analysis was successfully achieved in all patients. Results: Successful surgical resection was achieved in all patients. Mean cardiopulmonary bypass and cross-clamping times were 75 ± 36 and 41 ± 22 min, respectively. The most common tumor location was the left atrium (n = 42, 82.4%). Mean ventilation time was 12.74 ± 17.23 h, intensive care unit stay ranged from 1 to 1.9 days (median: 1 day). Nineteen patients (37.3%) received concomitant surgery. Histopathological analysis showed 38 myxoma (74.5%), 9 papillary fibroelastoma (17.6%), and 4 thrombus (7.8%). Thirty-day mortality was observed in 1 case (2%). One patient (2%) suffered a stroke postoperatively. No patient had a relapse of cardiac tumor. Three patients (9.7%) showed arterial embolization during follow-up. Thirteen follow-up patients (25.5%) were in New York Heart Association class ≤II. Overall survival was 90.2% at 2 years. Conclusions: A minimally invasive approach for benign atrial tumor resection is effective, safe, and reproducible. Of the atrial tumors, 74.5% were myxoma and 82% were located in the left atrium. A low 30-day mortality rate with no manifestation of recurrent intracardiac tumor was observed. Visual abstract

TOP2: Miniature Extravascular Aortic Sensor for Continuous Blood Pressure Measurement: In-vivo Validation Under Pathological Conditions

Abstract: Purpose of the Study: In individuals suffering from cardiovascular diseases, and especially in heart failure patients supported with left ventricular assist devices (VADs), the long-term monitoring of arterial blood pressure (ABP) holds significant value for assessing the disease progression, monitoring patient compliance, and evaluating the treatment efficacy. Hence, it is imperative to advance and extensively validate new, accurate and robust sensory technologies for this purpose. Methods: The present study aimed to evaluate the performance of a newly developed hall-based magnetic aortic sensor (HBSD) in monitoring arterial blood pressure (ABP) in conditions of low pulse pressures that simulate the hemodynamic conditions of VAD supported patients (Magkoutas et al, JACC: Basic to Translational Science, 2023). To this end, twelve acute in-vivo experiments were performed using pigs that were connected to a cardiopulmonary bypass circuit, and their hemodynamic state was regulated through adjustments to the support rate and pharmacological stimulation. In each experiment, two HBSDs were implanted, one in the ascending and one in the descending aorta. The reference ABP measurements were obtained using an intravascular fluid-filled catheter. Results: The pressure signal provided by the HBSD accurately captured the highly varying pressure profiles, regardless of the pressure level, CPB support level, and effective pulse pressure. The analysis of the difference between the end-diastolic (EDP), systolic (SP), and mean arterial (MAP) pressure values measured with the HBSDs and the reference sensors (Figure 1B) demonstrates that the HBSDs provide highly accurate measurements with a mean absolute error less than 5 mm Hg, except for two cases. Furthermore, the comparison of the entire dataset of the HBSD and the reference sensor during one of the in-vivo experiments reveals a high linear association between the two methods, confirmed by an intraclass coefficient higher than 0.95 (Figure 1C). The results of the Bland-Altman plot in Figure 1D also indicate that the developed HBSD has a mean bias of 0 mmHg, with limits of agreement approximately equal to 8.5 mmHg, compared to the reference pressure sensor. Conclusion: This study provides evidence supporting the accuracy of the proposed HBSD in measuring the ABP waveform in pathological and varying hemodynamic conditions. This constitutes a crucial preliminary stage in advancing the HBSD towards clinical utilization, thereby unlocking the valuable information contained in the ABP waveform and enhancing patient surveillance and therapeutic intervention in individuals supported by VADs.Figure 1. A) Implantation procedure and components of the hall-based aortic sensor. B) Boxplots of the difference between the end-diastolic (EDP), systolic (SP), and mean arterial (MAP) pressure values measured with the HBSDs and the reference sensors. C) The intraclass coefficient (ICC) with 95% confidence intervals for the ABP measured with the HBSD and the reference ABP. D) Bland-Altman plot with the representation of the mean difference, the limits of agreement (LoA) (dashed line) from −1.96s to +1.96s, and 95% confidence intervals (CI).

Mechanistic assessment and ablation of left ventricular assist device related ventricular tachycardia in patients with severe heart failure

Abstract: Aims: Left-ventricular-assist-devices (lvad) are an established treatment for patients with severe heart failure with reduced ejection fraction (HF) and reduce mortality. However, HF patients have significant substrate for ventricular tachycardia (VT) and the lvad itself might be pro-arrhythmogenic. We investigated the mechanism of VT in lvad-patients in relation to the underlying etiology and provide in silico and ex-vivo data for ablation in these HF patients. Methods and Results: We retrospectively analyzed invasive electrophysiological (EP) studies of 17 patients with VT and lvad. The mechanism of VT was determined using electroanatomical, entrainment and activation time mapping. Ischemic cardiomyopathy was present in 70% of patients. VT originated from the lvad region in >30%. 1/6 patients with VT originating from the lvad region had episodes before lvad implantation, while 7/11 patients with VT originating from other regions had episodes before implantation. Number and time of radiofrequency (RF)-ablation lesions were not different between VTs originating from the lvad or other regions. Long-term freedom from VT was 50% upon ablation in patients with VT originating from the lvad region and 64% if ablation was conducted in other regions. To potentially preemptively mitigate lvad related VT in patients undergoing lvad implantation, we obtained in silico derived data and performed ex-vivo experiments targeting ventricular myocardium. Of the tested settings, application of 25 W for 30 s was safe and associated with optimal lesion characteristics. Conclusion: A significant percentage of patients with lvad undergoing VT ablation exhibit arrhythmia originating in close vicinity to the device and recurrence rates are high. Based on in silico and ex-vivo data, we propose individualized RF-ablation in selected patients at risk for/with lvad related VT.

Transposition of the Greater Omentum into the Mediastinum for Treatment of Infected Prosthetic Grafts of the Ascending Aorta and Aortic Arch

Abstract: Background: Prosthetic graft infection of the ascending aorta and aortic arch requires in situ reconstruction due to close location to the heart. Transposition of the greater omentum into the mediastinum and coverage of the new graft with the omentum is an additional measure to protect the suture line from reinfection by enhancing microbiological resistance. In high-risk patients it may be a solely surgical treatment as a palliative therapy by wrapping the old, infected prosthetic graft. This surgical procedure is barely performed for the treatment of infected aortic graft prostheses.

“UFO procedure” for massive aortic and mitral annular calcification involving left atrial and ventricular myocardium: a potential radical solution

Abstract: The "UFO procedure" was initially developed as a surgical option to enlarge the aortic annulus in patients requiring valve replacement. This technique can be employed to treat extensive endocarditis located in the intervalvular fibrous body (IVFB). One of the indications for a "UFO procedure" is massive aortic and mitral valve calcification. It is a challenging surgical procedure with a high risk of intraoperative complications. We present a 76-year-old male patient with massive aortic and mitral valve calcification involving the left atrium, the left ventricle and the left ventricular outflow tract. Both valves exhibited severe stenosis and moderate to severe regurgitation. The left ventricle was hypertrophic and the left ventricular ejection fraction was > 55%. The patient was prediagnosed with persistent atrial fibrillation. The risk of death following heart surgery (EuroSCORE II) was calculated as 9.21%. We successfully performed a so-called "UFO procedure" including replacement of both valves without annular decalcification to avoid atrioventricular dehiscence. We enlarged the IVFB and replaced the non-coronary sinus of Valsalva with doubled bovine pericardium. The left ventricular outflow tract was decalcified. The patient was transferred to a local hospital on the 13th postoperative day.Successful surgical treatment to this extent was demonstrated for the first time. Due to the high perioperative mortality, the surgical treatment of patients with this constellation would be refused in most cases. In our patient, the preoperative imaging showed extreme calcification of both valves and the surrounding myocardium. Excellent preoperative planning and a highly experienced surgical team is necessary.