Aortic valved homograft degeneration: surgical or transcatheter approach for repeat aortic valve replacement?

OBJECTIVES: Aortic valved allografts (homografts) have been used alternatively to mechanical or biological valve prostheses in expectation of better durability; however, homograft valves do degenerate, and redo procedures have proven challenging due to heavy wall calcification. The aim of the study was to compare the outcome of open surgical (SAVR) and transcatheter aortic valve replacement (TAVR) in degenerated homografts. METHODS: Between 1993 and 2022, 81 patients underwent repeat aortic valve procedures having previously received an aortic homograft. The redo had become necessary due to regurgitation in 85% and stenosis in 15%. Sixty-five percent underwent open surgery, 35% TAVR. RESULTS: Isolated SAVR was possible in 79%, and root procedures were necessary in 21%. TAVR was performed in 79% via transfemoral and 21% via transapical access. Median prosthetic valve size was 23 (22.3-23.2) mm in the SAVR and 26 (25.2-26.9) in the TAVR group. Thirty-day mortality was 0% in the TAVR and 7% in the SAVR group (P = n.s.). TAVR showed a significantly better outcome concerning prolonged ventilation (0 vs 21%, P = 0.013) as well as ICU (1 vs 2 days; P < 0.001) and in-hospital stay (10.5 vs 13 days; P = 0.028). Five-year survival was statistically comparable between groups, and no severe leakage was observed. CONCLUSIONS: SAVR following structural homograft degeneration shows acceptable results, but the perioperative risk remains substantial and poorly predictable. TAVR presents a reasonable and more easily accessible alternative and is associated with good short- and mid-term results. In the absence of relevant contraindications, TAVR is presently the preferred treatment option for these patients at our center.

Quantification of physical activity with prospective activity tracking after transfemoral aortic valve replacement.

BACKGROUND: Transcatheter aortic valve replacement (TAVR) is a well-established, safe and effective therapy for severe symptomatic aortic stenosis (AS). The aim of this study was to objectively quantify improvement of physical activity after TAVR, with consideration of different low-gradient AS subtypes. METHODS AND RESULTS: All patients undergoing TAVR for severe AS were screened. Participants received a wearable activity tracker (Fitbit®) at hospital discharge following TAVR and 6 months thereafter. The difference of median daily steps was defined as surrogate outcome for physical activity. For analysis, patients were grouped into high-gradient (HG) AS (dPmean ≥40 mmHg), classical low-flow low-gradient (LFLG) AS (dPmean <40 mmHg, EF <50%), paradoxical LFLG-AS (dPmean <40 mmHg, EF ≥50%, SVi ≤35 ml/m2) and normal-flow low-gradient (NFLG) AS (dPmean <40 mmHg, EF ≥50%, SVi >35 ml/m2) according to mean transvalvular pressure gradient (dPmean), stroke volume index (SVi) and left-ventricular ejection fraction (LVEF). RESULTS AND CONCLUSIONS: The analysis is based on 230 patients. The median daily step count was 4409 [IQR 2581-7487] after hospital discharge and 5326 [IQR 3045-8668] 6 months thereafter. Median difference of daily steps was ∆529 [IQR -702-2152]). Patients with HG-AS and paradoxical LFLG-AS showed a significant improvement of daily steps (∆951 [IQR -378-2323], p <0.001 and (∆1392 [IQR -609-4444], p = 0.02, respectively). Patients with classical LFLG-AS showed no statistically relevant improvement of daily steps (∆192 [IQR -687-770], p = 0.79). Patients with NFLG-AS showed a numerical decline in daily steps without statistical significance (∆-300 [IQR -1334-1406], p = 0.67). This first prospective study of this sample size shows significant improvement of physical activity after TAVR with an objective and reproducible method. This was mainly driven by an improvement in patients with HG-AS and paradoxical LFLG-AS.

TAVI for patients with normal-flow low-gradient compared to high-gradient aortic stenosis.

BACKGROUND: Normal-flow (stroke volume index, SVi >35 ml/m2) low-gradient (dPmean <40 mmHg) aortic stenosis (NFLG-AS) is subject of scientific debate. Guidelines fail to give conclusive treatment recommendations. We hypothesized that NFLG patients are heterogenous, containing a subgroup similar to high-gradient aortic stenosis patients (dPmean ≥40 mmHg, HG-AS) concerning characteristics and outcomes. METHODS: 2326 patients undergoing transcatheter aortic valve replacement (TAVI) at our centre between 2013 and 2019 were analysed. 386 patients fulfilled criteria of NFLG-AS. Their median dPmean was 33 mmHg, which was used for grouping (204 patients with higher gradient NFLG-AS, 186 patients with lower gradient NFLG-AS). They were compared to 956 HG-AS patients. RESULTS: Characteristics of lower gradient NFLG-AS patients differed from HG-AS patients in many aspects while higher gradient NFLG-AS and HG-AS patients were mostly similar, underscored by higher Society of Thoracic Surgeons scores in lower gradient NFLG-AS (lower gradient NFLG-AS, 3.9, HG-AS, 3.0, p = 0.03, higher gradient NFLG-AS, 3.0, p = 0.04). Procedural complications were comparable. Estimated 3-year all-cause mortality was higher in lower gradient NFLG-AS compared to HG-AS patients (hazard ratio 1.7, p < 0.01), whereas mortality of higher gradient NFLG-AS was similar to HG-AS patients (hazard ratio 1.2, p = 0.31). Cardiovascular mortality was highest among lower gradient NFLG-AS patients (21.6% vs. higher gradient NFLG-AS, 15.4%, vs. HG-AS, 11.1%, p < 0.01). CONCLUSIONS: NFLG-AS patients are indeed heterogenous. NFLG-AS patients with higher gradients resemble HG-AS patients in clinical characteristics and outcomes and should not be treated differently. Lower gradient NFLG-AS patients have increased long-term mortality and the use of TAVI requires careful consideration.

Dual ProGlide versus ProGlide and FemoSeal for vascular access haemostasis after transcatheter aortic valve implantation.

BACKGROUND: Large-bore arteriotomy for transcatheter aortic valve implantation (TAVI) requires percutaneous vascular closure devices, but real-world data comparing different closure strategies are limited. AIMS: We sought to compare a dual ProGlide strategy vs a combination of one ProGlide and one FemoSeal for vascular closure after TAVI. METHODS: We retrospectively analysed 874 propensity score-matched patients undergoing TAVI at the Munich University Hospital from August 2018 to October 2020. From August 2018 to August 2019, a dual ProGlide strategy was used for vascular closure. From October 2019 to October 2020, a combination of one ProGlide and one FemoSeal was used. The primary endpoint was defined as access-related major vascular complications or bleeding ≥Type 2 according to Valve Academic Research Consortium 3 criteria. RESULTS: Patients in the dual ProGlide group (n=437) had a higher incidence of the primary endpoint than patients treated with one ProGlide and one FemoSeal (n=437; 11.4% vs 3.0%; p<0.001). Furthermore, they had a higher rate of closure device failure (2.7% vs 0.9%; p=0.044) and more often required unplanned surgery or endovascular treatment (3.9% vs 0.9%; p=0.004). The incidence of death did not differ significantly between groups (3.4% vs 1.6%; p=0.08). CONCLUSIONS: A combined ProGlide and FemoSeal strategy might have the potential to reduce access-related vascular complications following TAVI.

TAVI in patients with low-flow low-gradient aortic stenosis-short-term and long-term outcomes.

OBJECTIVES: The study objective was to characterize different groups of low-flow low-gradient (LFLG) aortic stenosis (AS) and determine short-term outcomes and long-term mortality according to Valve Academic Research Consortium-3 (VARC-3) endpoint definitions. BACKGROUND: Characteristics and outcomes of patients with LFLG AS undergoing transcatheter aortic valve implantation (TAVI) are poorly understood. METHODS: All patients undergoing TAVI at our center between 2013 and 2019 were screened. Patients were divided into three groups according to mean pressure gradient (dPmean), ejection fraction (LVEF), and stroke volume index (SVi): high gradient (HG) AS (dPmean ≥ 40 mmHg), classical LFLG (cLFLG) AS (dPmean < 40 mmHg, LVEF < 50%), and paradoxical LFLG (pLFLG) AS (dPmean < 40 mmHg, LVEF ≥ 50%, SVi ≤ 35 ml/m2). RESULTS: We included 1776 patients (956 HG, 447 cLFLG, and 373 pLFLG patients). Most baseline characteristics differed significantly. Median Society of Thoracic Surgeons (STS) score was highest in cLFLG, followed by pLFLG and HG patients (5.0, 3.9 and 3.0, respectively, p < 0.01). Compared to HG patients, odds ratios for the short-term VARC-3 composite endpoints, technical failure (cLFLG, 0.76 [95% confidence interval, 0.40-1.36], pLFLG, 1.37 [0.79-2.31]) and device failure (cLFLG, 1.06 [0.74-1.49], pLFLG, 0.97 [0.66-1.41]) were similar, without relevant differences within LFLG patients. NYHA classes improved equally in all groups. Compared to HG, LFLG patients had a higher 3-year all-cause mortality (STS score-adjusted hazard ratios, cLFLG 2.16 [1.77-2.64], pLFLG 1.53 [1.22-193]), as well as cardiovascular mortality (cLFLG, 2.88 [2.15-3.84], pLFLG, 2.08 [1.50-2.87]). CONCLUSIONS: While 3-year mortality remains high after TAVI in LFLG compared to HG patients, symptoms improve in all subsets after TAVI.

In-depth profiling of COVID-19 risk factors and preventive measures in healthcare workers.

PURPOSE: To determine risk factors for coronavirus disease 2019 (COVID-19) in healthcare workers (HCWs), characterize symptoms, and evaluate preventive measures against SARS-CoV-2 spread in hospitals. METHODS: In a cross-sectional study conducted between May 27 and August 12, 2020, after the first wave of the COVID-19 pandemic, we obtained serological, epidemiological, occupational as well as COVID-19-related data at a quaternary care, multicenter hospital in Munich, Germany. RESULTS: 7554 HCWs participated, 2.2% of whom tested positive for anti-SARS-CoV-2 antibodies. Multivariate analysis revealed increased COVID-19 risk for nurses (3.1% seropositivity, 95% CI 2.5-3.9%, p = 0.012), staff working on COVID-19 units (4.6% seropositivity, 95% CI 3.2-6.5%, p = 0.032), males (2.4% seropositivity, 95% CI 1.8-3.2%, p = 0.019), and HCWs reporting high-risk exposures to infected patients (5.5% seropositivity, 95% CI 4.0-7.5%, p = 0.0022) or outside of work (12.0% seropositivity, 95% CI 8.0-17.4%, p < 0.0001). Smoking was a protective factor (1.1% seropositivity, 95% CI 0.7-1.8% p = 0.00018) and the symptom taste disorder was strongly associated with COVID-19 (29.8% seropositivity, 95% CI 24.3-35.8%, p < 0.0001). An unbiased decision tree identified subgroups with different risk profiles. Working from home as a preventive measure did not protect against SARS-CoV-2 infection. A PCR-testing strategy focused on symptoms and high-risk exposures detected all larger COVID-19 outbreaks. CONCLUSION: Awareness of the identified COVID-19 risk factors and successful surveillance strategies are key to protecting HCWs against SARS-CoV-2, especially in settings with limited vaccination capacities or reduced vaccine efficacy.

Health promoting behaviour of medical versus non-medical students during COVID-19 pandemic: results from the COLA cross-sectional study.

To investigate the COVID-19 pandemic related alteration of health promoting behaviour during lockdown among medical students compared to other students.In this cross-sectional study, we enrolled 1940 Bavarian students. Participants were asked to complete an online questionnaire 3 weeks after lockdown implementation, evaluating their lifestyle behaviour focusing on self-reported and objectively assessed physical activity.1154 medical (59.5%) and 786 non-medical (40.5%) students were included (median age 22.0 [IQR, 20.0-25.0], 71.5% female). Physical activity decreased in both groups after lockdown implementation. During lockdown, medical students reported higher physical activity levels compared to non-medical students. This was corroborated by daily step count data assessed by wearables (median steps per day [IQR], 6979 [5218-9348] versus 6581 [4497-8491], p = 0.02). Smoking behaviour during lockdown did not differ between medical and non-medical students (increased in 11.8% vs 13.6%, decreased in 31.9% versus 36.9%).During the COVID-19 pandemic, alteration of lifestyle behaviour among medical students was significantly different compared to non-medical students. This result suggests that medical students are more concerned about health promoting behaviour even in crisis situations.

Selective bispecific T cell recruiting antibody and antitumor activity of adoptive T cell transfer.

BACKGROUND: One bottleneck for adoptive T cell therapy (ACT) is recruitment of T cells into tumors. We hypothesized that combining tumor-specific T cells, modified with a marker antigen and a bispecific antibody (BiAb) that selectively recognizes transduced T cells and tumor cells would improve T cell recruitment to tumors and enhance therapeutic efficacy. METHODS: SV40 T antigen-specific T cells from T cell receptor (TCR)-I-transgenic mice were transduced with a truncated human epidermal growth factor receptor (EGFR) as a marker protein. Targeting and killing by combined ACT and anti-EGFR-anti-EpCAM BiAb therapy was analyzed in C57Bl/6 mice (n = six to 12 per group) carrying subcutaneous tumors of the murine gastric cancer cell line GC8 (SV40(+) and EpCAM(+)). Anti-EGFR x anti-c-Met BiAb was used for targeting of human tumor-specific T cells to c-Met(+) human tumor cell lines. Differences between experimental conditions were analyzed using the Student's t test, and differences in tumor growth with two-way analysis of variance. Overall survival was analyzed by log-rank test. All statistical tests were two-sided. RESULTS: The BiAb linked EGFR-transduced T cells to tumor cells and enhanced tumor cell lysis. In vivo, the combination of ACT and Biab produced increased T cell infiltration of tumors, retarded tumor growth, and prolonged survival compared with ACT with a control antibody (median survival 95 vs 75 days, P < .001). In human cells, this strategy enhanced recruitment of human EGFR-transduced T cells to immobilized c-Met and recognition of tyrosinase(+) melanoma cells by TCR-, as well as of CEA(+) colon cancer cells by chimeric antigen receptor (CAR)-modified T cells. CONCLUSIONS: BiAb recruitment of tumor-specific T cells transduced with a marker antigen to tumor cells may enhance efficacy of ACT.

Diffusion of molecular diagnostic lung cancer tests: a survey of german oncologists.

This study was aimed at examining the diffusion of diagnostic lung cancer tests in Germany. It was motivated by the high potential of detecting and targeting oncogenic drivers. Recognizing that the diffusion of diagnostic tests is a conditio sine qua non for the success of personalized lung cancer therapies, this study analyzed the diffusion of epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) tests in Germany. Qualitative and quantitative research strategies were combined in a mixed-method design. A literature review and subsequent Key Opinion Leader interviews identified a set of qualitative factors driving the diffusion process, which were then translated into an online survey. The survey was conducted among a sample of 961 oncologists (11.34% response rate). The responses were analyzed in a multiple linear regression which identified six statistically significant factors driving the diffusion of molecular diagnostic lung cancer tests: reimbursement, attitude towards R&D, information self-assessment, perceived attitudes of colleagues, age and test-pathway strategies. Besides the important role of adequate reimbursement and relevant guidelines, the results of this study suggest that an increasing usage of test-pathway strategies, especially in an office-based setting, can increase the diffusion of molecular diagnostic lung cancer tests in the future.

Technological evolution of diagnostic testing in oncology.

Diagnostic testing has been improving the quality of cancer care. The dynamics of this field can be grasped through the application of innovation lifecycle models. Single testing, parallel testing and whole-genome sequencing are major technological evolutions. Given the increasing availability of biomarkers, the performance of single testing will be limited in the future, favoring the further implementation of parallel testing technologies. Whole-genome sequencing will lead to a further performance increase by introducing the era of genomic medicine. A broad adoption of presently available diagnostic technologies sets up the infrastructure for future technologies. The speed at which these technologies are introduced depends heavily on the regulatory and reimbursement environment, while their final diffusion is subject to pragmatic criteria such as user friendliness, perceived risk and perceived value added.