Publications by authors named "Christoph Gross"

Background: Oscillometry devices allow quantification of respiratory function at tidal breathing but device-specific reference equations are scarce: the present study aims to create sex-specific oscillometric reference values for children and adolescents using the Resmon PRO FULL device.

Methods: Healthy participants (n=981) aged 6 to 17 years of the Austrian LEAD general population cohort were included. Subjects had normal weight (body mass index ≤99th percentile) and normal lung volumes (total lung capacity (TLC) ≥ lower limit of normal).

View Article and Find Full Text PDF

Chiral isochalcogenoureas ( isothioureas and isoselenoureas) catalyse the asymmetric (4 + 2)-cycloaddition of various allenoates with -quinone methides. This approach provides straightforward access to different chromane derivatives with high enantioselectivities, good yields, and control of the configuration of the exocyclic double bond. Furthermore, some of the novel -quinone methides used herein were successfully integrated into the Mayr reactivity scale by determining their electrophilicity parameter.

View Article and Find Full Text PDF

In patients with airflow obstruction, the levels of biomarkers of Type-2 (T2) inflammation serve to predict the effectiveness of inhaled corticosteroid and biological therapies. Elevated biomarkers of T2 inflammation, including fractional exhaled nitric oxide (FeNO, ≥20 ppb) and blood eosinophil counts (BEC, ≥300 cells/µL), were investigated in a population-based cohort of the Austrian LEAD study. A total of 4976 individuals (aged 18-82 years) were categorised into four groups based on their FeNO and BEC levels: normal with FeNO < 20 ppb and BEC < 300 cells/µL (n = 2634); FeNO ≥ 20 ppb only (n = 1623); BEC ≥ 300 cells/µL only (n = 340); and FeNO ≥ 20 ppb and BEC ≥ 300 cells/µL (n = 379).

View Article and Find Full Text PDF

A series of aryl-substituted ortho-quinone methides (oQMs) was synthesised and structurally characterised. Kinetic studies of the nucleophilic additions of carbanions (reference nucleophiles) to oQMs were used to determine second-order rate constants k for the carbon-carbon bond forming reactions (20 °C, DMSO) at the oQMs' exocyclic π-bond. Analysing the kinetic data by the linear free energy relationship lg k=s(N+E) revealed the Mayr electrophilicities E of the oQMs.

View Article and Find Full Text PDF

Pulsatile hemodynamics have been shown to be independent predictors of cardiovascular events. The aim of the current study was to describe four pulsatile hemodynamic markers in a large, well-established, population-based cohort and to provide reference equations for sex- and age-based standardization of these measurements. 6828 adult participants from the Austrian LEAD (Lung, hEart, sociAl, boDy) cohort study, who were free from overt cardiovascular disease, non-diabetic based on blood test results, and had no history of pharmacological treatment for hypertension, dyslipidemia, and diabetes, comprised the "reference population".

View Article and Find Full Text PDF

Accurate activity classification is essential for the advancement of closed-loop control for left ventricular assist devices (LVADs), as it provides necessary feedback to adapt device operation to the patient's current state. Therefore, this study aims at using deep neural networks (DNNs) to precisely classify activity for these patients. Recordings from 13 LVAD patients were analyzed, including heart rate, LVAD flow, and accelerometer data, classifying activities into six states: active, inactive, lying, sitting, standing, and walking.

View Article and Find Full Text PDF

Background: Temporal trends of routinely obtained parameters may provide valuable information for predicting BSIs, but this association has not yet been established in LVAD patients.

Methods: This retrospective analysis included data from 347 consecutive recipients of three rotary LVAD types. Study endpoints included the incidence of BSI, the association of temporal trends of routinely obtained blood biomarkers with the development of BSIs, the incidence of BSIs, and survival on LVAD support.

View Article and Find Full Text PDF

Preserved ratio impaired spirometry (PRISm) is a recently recognized spirometric pattern defined by a ratio of forced expiratory volume in 1 second to forced vital capacity of at least 0.70 and a forced expiratory volume in 1 second  <80% of reference. For unclear reasons, PRISm is associated with increased cardiovascular (CV) morbidity and mortality.

View Article and Find Full Text PDF

Purpose: A new automated expanded polytetrafluoroethylene (ePTFE) suture placement device and a new customized titanium fastener deployment device were clinically evaluated in open and less-invasive mitral valve repair (MVr).

Description: Twelve patients were monitored for 1 year after undergoing MVr using the study devices. The study end points included surgical outcomes, operative times, valve repair durability, adverse events, and mortality.

View Article and Find Full Text PDF

Effective treatment of heart failure with preserved ejection fraction (HFpEF) remains an unmet medical need. Although left atrial decompression using mechanical circulatory support devices was previously suggested, the heterogeneous HFpEF population and the lack of tailored devices have prevented the translation into clinical practice. This study aimed to evaluate the feasibility of left atrial decompression in HFpEF patients with a HeartMate 3 (HM3, Abbott Inc, Chicago, USA) in silico and in vitro .

View Article and Find Full Text PDF

Purpose: The HeartMate 3 (HM3) left ventricular assist device (LVAD) has demonstrated excellent clinical outcomes; however, pump speed optimization is challenging with the available HM3 monitoring. Therefore, this study reports on clinical HM3 parameters collected with a noninvasive HM3 monitoring system (HM3 Snoopy) during echocardiographic speed ramp tests and Valsalva maneuvers.

Methods: In this prospective, single-center study, the HM3 data communication between the controller and pump was recorded with a novel data acquisition system.

View Article and Find Full Text PDF

Ventricular assist devices (LVADs) are a valuable therapy for end-stage heart failure patients. However, some adverse events still persist, such as suction that can trigger thrombus formation and cardiac rhythm disorders. The aim of this study is to validate a suction module (SM) as a test bench for LVAD suction detection and speed control algorithms.

View Article and Find Full Text PDF

Purpose: Exercise performance and quality of life (QoL) of left ventricular assist device (LVAD) patients improve after early cardiac rehabilitation (CR). The purpose of this study was to examine the efficacy of multiprofessional long term phase 3 outpatient CR, and whether cardiopulmonary exercise testing (CPX) and 6-min walk testing (6MWT) post-LVAD implantation predict hospital readmission.

Methods: This retrospective observational cohort study included 29 LVAD patients (58.

View Article and Find Full Text PDF

Objective: This study evaluated the ergonomics and time requirements of using a novel automated suturing and titanium fastener deployment technology for chordal replacement in human heart specimens in open and minimally invasive cardiac surgery (MICS) simulators.

Methods: Five cardiac surgeons used novel, manually powered expanded polytetrafluoroethylene (ePTFE) suturing devices to automate suture placement between mitral leaflets and papillary muscles in explanted cadaver hearts, along with customized titanium fastener delivery devices to secure suture and trim suture tails. This mitral chordal replacement test was conducted using surgical models simulating open and MICS mitral repair access.

View Article and Find Full Text PDF

Atrial fibrillation (AF) is a common comorbidity in left ventricular assist device (LVAD) patients and has been identified as a risk factor for thromboembolic stroke. Blood stagnation within the left atrial appendage (LAA) is considered a possible major source of thrombosis and clinical studies have shown reduced thromboembolic risk after LAA occlusion (LAAO). Therefore, this study aims to investigate the effect of LAAO on thrombosis-related parameters using patient-specific simulations.

View Article and Find Full Text PDF

Background: The use of polytetrafluoroethylene (PTFE) material as a protective cover for left ventricular assist device (LVAD) outflow grafts (OG) is a common practice. However, it has descriptively been linked to the development of blood flow obstruction (BFO).

Methods: Patient data from 194 consecutive HVAD (Medtronic Inc; Medtronic, Minneapolis, MN) recipients implanted between March 2006 and January 2021 were retrospectively analyzed.

View Article and Find Full Text PDF

Transcatheter aortic valve replacement (TAVR) has become a cornerstone in today's treatment of aortic stenosis. Modern transcatheter prostheses are continuously evolving and each one features different design traits. In this review, the authors provide insight in the technical differences of current prostheses and TAVR related clinical decision pathways, preferably useful for the beginners but also for advanced operators.

View Article and Find Full Text PDF

Background: Contemporary Left Ventricular Assist Devices (LVADs) mainly operate at a constant speed, only insufficiently adapting to changes in patient demand. Automatic physiological speed control promises tighter integration of the LVAD into patient physiology, increasing the level of support during activity and decreasing support when it is excessive.

Methods: A sensorless modular control algorithm was developed for a centrifugal LVAD (HVAD, Medtronic plc, MN, USA).

View Article and Find Full Text PDF

Advanced stage heart failure patients can benefit from the unloading effects of an implantable left ventricular assist device. Despite best clinical practice, LVADs are associated with adverse events, such as pump thrombosis (PT). An adaptive algorithm alerting when an individual's appropriate levels in pump power uptake are exceeded, such as in the case of PT, can improve therapy of patients implanted with a centrifugal LVAD.

View Article and Find Full Text PDF

Successful therapy of heart failure with preserved ejection fraction (HFpEF) remains a major unmet clinical need. Device-based treatment approaches include the interatrial shunt device (IASD), conventional assist devices pumping blood from the left ventricle (LV-VAD) or the left atrium (LA-VAD) towards the aorta, and a valveless pulsatile assist device with a single cannula operating in co-pulsation with the native heart (CoPulse). Hemodynamics of two HFpEF subgroups during rest and exercise condition were translated into a lumped parameter model of the cardiovascular system.

View Article and Find Full Text PDF

Background: Research integrating multisensory home-monitoring in respiratory disease is scarce. Therefore, we created a novel multisensory home-monitoring device tailored for long-term respiratory disease management (named the CAir-Desk). We hypothesize that recent technological accomplishments can be integrated into a multisensory participant-driven platform.

View Article and Find Full Text PDF

Transcatheter aortic valve replacement (TAVR) has rapidly become a viable alternative to the conventional isolated surgical aortic valve replacement (iSAVR) for treating severe symptomatic aortic stenosis. However, data on younger patients is scarce and a gap exists between data-based recommendations and the clinical use of TAVR. In our study, we utilized a machine learning (ML) driven approach to model the complex decision-making process of Heart Teams when treating young patients with severe symptomatic aortic stenosis with either TAVR or iSAVR and to identify the relevant considerations.

View Article and Find Full Text PDF

Ventricular suction is a frequent adverse event in patients with a ventricular assist device (VAD). This study presents a suction module (SM) embedded in a hybrid (hydraulic-computational) cardiovascular simulator suitable for the testing of VADs and related suction events. The SM consists of a compliant latex tube reproducing a simplified ventricular apex.

View Article and Find Full Text PDF

Objectives: We reviewed our institutional experience with outflow graft stenosis (OGS) in 3 contemporary left ventricular assist devices (LVAD).

Methods: Data from 347 consecutive adult recipients of LVAD [Medtronic HVAD (n = 184, 53.0%), Abbott HeartMate II (n = 62, 17.

View Article and Find Full Text PDF

Background: Younger patients with severe symptomatic aortic stenosis are a particularly challenging collective with regard to the choice of intervention. High-risk patients younger than 75 years of age are often eligible for both the transcatheter aortic valve replacement (TAVR) and the isolated surgical aortic valve replacement (iSAVR). Data on the outcomes of both interventions in this set of patients are scarce.

View Article and Find Full Text PDF

A PHP Error was encountered

Severity: Warning

Message: fopen(/var/lib/php/sessions/ci_sessioniojf8nic9v0nubmkf42onhlrt59i5q0u): Failed to open stream: No space left on device

Filename: drivers/Session_files_driver.php

Line Number: 177

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: session_start(): Failed to read session data: user (path: /var/lib/php/sessions)

Filename: Session/Session.php

Line Number: 137

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once