Tim Walter

Mr. Tim Walter

orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 February 2021 in European Journal of Cardio-Thoracic Surgery
Verified
Journal Article
Closed access
MKMaximilian Kreibich
Maximilian Kreibich
MSMatthias Siepe
Matthias Siepe
TBTim Berger
Tim Berger
CPClarence Pingpoh
Clarence Pingpoh
PPPaul Puiu
Paul Puiu
MCMartin Czerny
Martin Czerny
OBJECTIVES: Our aim was to evaluate the mid-term outcomes of bovine pericardial tube graft repair for infectious aortic disease in any aortic segment. METHODS: Between May 2015 and July 2020, 45 patients were treated for infectious aortic disease of the native (n = 9) aorta or after (endo-)graft (n = 36) implantation with bovine pericardial tube grafts. Clinical, infectious details, outcomes and follow-up data were evaluated. RESULTS: All aortic segments underwent pericardial tube graft or bifurcational replacement: the aortic root (n = 12, 27%), ascending aorta (n = 18, 40%), aortic arch (n = 7, 16%), descending aorta (n = 5, 11%), thoraco-abdominal aorta (n = 6, 13%) and abdominal aorta (n = 18, 40%) including the iliac arteries (n = 14, 31%). Organ fistulation (n = 15, 33%) was the most common underlying pathology. Seven patients (16%) expired in-hospital secondary to ongoing sepsis (n = 5, 11%), respiratory failure (n = 1, 2%) and unknown cause (n = 1, 2%). A fungal infection was predictive for in-hospital mortality (P = 0.026, odds ratio: 19.470). After a median follow-up of 11 [first quartile: 2, third quartile 26] months, 9 additional patients (20%) expired and 1 patient developed a postoperative spondylodiscitis at the level of the aortic tube graft. Hence, freedom from proven aortic graft re-infection was 98%. CONCLUSIONS: Orthotopic aortic reconstruction using bovine pericardial tube grafts to treat infectious aortic disease is possible in any aortic segment. Organ fistulation is a frequently observed disease mechanism requiring concomitant treatment. Granted, the early attrition rate is substantial, but after the initial period, both survival and freedom from re-infection appear encouraging.

4 January 2021 in European Journal of Cardio-Thoracic Surgery
Verified
Journal Article
Closed access
MCMartin Czerny
Martin Czerny
RGRoman Gottardi
Roman Gottardi
PPPaul Puiu
Paul Puiu
OBOliver Y Bernecker
Oliver Y Bernecker
Rodolfo CitroRodolfo Citro
Rodolfo Citro
EWErnst Weigang
Ernst Weigang
: OBJECTIVES: To evaluate the impact of the coronavirus disease 2019 (COVID-19) pandemic on acute and elective thoracic and abdominal aortic procedures. METHODS: Forty departments shared their data on acute and elective thoracic and abdominal aortic procedures between January and May 2020 and January and May 2019 in Europe, Asia and the USA. Admission rates as well as delay from onset of symptoms to referral were compared. RESULTS: No differences in the number of acute thoracic and abdominal aortic procedures were observed between 2020 and the reference period in 2019 [incidence rates ratio (IRR): 0.96, confidence interval (CI) 0.89–1.04; P = 0.39]. Also, no difference in the time interval from acute onset of symptoms to referral was recorded ( 12 h 68% in 2020, < 12 h 34% vs > 12 h 66% in 2019 P = 0.29). Conversely, a decline of 35% in elective procedures was seen (IRR: 0.81, CI 0.76–0.87; P < 0.001) with substantial differences between countries and the most pronounced decline in Italy (−40%, P < 0.001). Interestingly, in Switzerland, an increase in the number of elective cases was observed (+35%, P = 0.02). CONCLUSIONS: There was no change in the number of acute thoracic and abdominal aortic cases and procedures during the initial wave of the COVID-19 pandemic, whereas the case load of elective operations and procedures decreased significantly. Patients with acute aortic syndromes presented despite COVID-19 and were managed according to current guidelines. Further analysis is required to prove that deferral of elective cases had no impact on premature mortality.

28 August 2022 in Biomedicines
Verified
Journal Article
Open access
PDF file
JSJasmin H. Shahinian
Jasmin H. Shahinian
CHCosima B. Hauser-Stadler
Cosima B. Hauser-Stadler
TWTim Walter
Tim Walter
PDPhilipp Discher
Philipp Discher
ISInes Derya Steenbuck
Ines Derya Steenbuck
Martin CzernyMartin Czerny
Martin Czerny
Aortic diseases are a rare but potentially life-threatening condition. We present a serum proteomic study for a spectrum of aortic diseases including thoracic aortic aneurysms (n = 11), chronic dissections (n = 9), acute aortic dissections (n = 11), and surgically treated dissections (n = 19) as well as healthy controls (n = 10) and patients of coronary heart disease (n = 10) to represent non-aortic cardiovascular disease. In total, we identified and quantified 425 proteins across all 70 samples. The different aortic diseases represented distinguishable proteome profiles. We identified protein clusters that positively or negatively correlate with disease severity, including increase of cytosolic tissue leakage proteins and decrease of components of the coagulation and complement system. Further, we identified a serum proteome fingerprint of acute aortic dissections, consisting, among others, of enriched inflammatory markers such as C-reactive protein and members of the S100 protein family. The study underlines the applicability of serum proteomics for the investigation of aortic diseases and highlights the possibility to establish disease-specific prognostic markers.

13 October 2023 in Medicina
Verified
Journal Article
Open access
PDF file
JBJulia Benk
Julia Benk
TBTim Berger
Tim Berger
RGRoman Gottardi
Roman Gottardi
TWTim Walter
Tim Walter
SKStoyan Kostadinov Kondov
Stoyan Kostadinov Kondov
MKMaximilian Kreibich
Maximilian Kreibich
Background and Objectives: The aim of this study was to analyze the influence of mass transfusion on the postoperative outcome and survival in patients presenting with acute Type A aortic dissection. Materials and Methods: Between 2002 and 2020, a total of 505 patients were surgically treated for an acute Type A aortic dissection. Mass transfusion was defined as the peri- and postoperative replacement by transfusion of 10 units. Patient characteristics and outcomes were analyzed and compared between patients with and without mass transfusion. Results: Mass transfusion occurred in 105 patients (20%). The incidences of symptomatic coronary malperfusion (p = 0.017) and tamponade (p = 0.043) were higher in patients with mass transfusion. There was no statistically significant difference in the distal extension of the aortic dissection between the two groups. A valved conduit was significantly more common in patients with mass transfusion (p = 0.007), while the distal aortic repair was similar between the two groups. Cardiopulmonary bypass time (p < 0.001), cross clamp time (p < 0.001) and in-hospital mortality were significantly higher in patients with mass transfusion (p < 0.001), but the survival after discharge (landmark-analysis) showed equal survival between patients with and without mass transfusion (log rank: p = 0.4). Mass transfusion was predictive of in-hospital mortality (OR: 3.308, p < 0.001) but not for survival after discharge (OR: 1.205, p = 0.661). Conclusions: Mass transfusion is necessary in many patients with acute Type A aortic dissection. These patients present sicker and require longer surgery. However, mass transfusion does not influence survival after discharge.

1 October 2023 in Journal of Clinical Medicine
Verified
Journal Article
Open access
PDF file
JBJulia Benk
Julia Benk
TBTim Berger
Tim Berger
SKStoyan Kostadinov Kondov
Stoyan Kostadinov Kondov
MDMatthias D’inka
Matthias D’inka
MBMagdalena Bork
Magdalena Bork
MKMaximilian Kreibich
Maximilian Kreibich
Background: Our aim was to investigate outcomes and long-term survival in male and female patients after frozen elephant trunk (FET) total arch replacement. Methods: Between March 2013 and January 2023, 362 patients underwent aortic arch replacement via the FET technique. We compared patient characteristics and intra- and postoperative data between male and female patients. Results: Male patients were significantly younger (p = 0.012) but revealed a higher incidence of coronary artery disease (p = 0.008) and preoperative dialysis (p = 0.017). More male patients presented with type A aortic dissections (p = 0.042) while more female patients had aortic aneurysms (p = 0.025). The aortic root was replaced in significantly more male patients (p = 0.013), resulting in significantly longer cardiopulmonary bypass duration (p < 0.001) and operative times (p < 0.001). There were no statistically significant differences in postoperative outcome parameters including in-hospital mortality (p = 0.346). However, new in-stent thrombus formation was significantly more frequent in female patients (p = 0.002). Age in years (odds ratio (OR): 1.026, p = 0.049), an acute pathology (OR: 1.941, p = 0.031) and preoperative dialyses (OR: 3.499, p = 0.010) were predictive for long-term mortality in our Cox regression model, sex (p = 0.466) was not. There was no statistical difference in overall survival (log rank: p = 0.425). Conclusions: Female patients are older but reveal fewer cardiovascular risk factors; aneurysms are more common in female than male patients. As female patients undergo concomitant surgical procedures less often, their operative times are shorter. While survival and outcomes were similar, female patients suffered from postoperative new in-stent thrombus formation significantly more often.

30 April 2023 in Seminars in Vascular Surgery
Verified
Journal Article
Open access
TWTim Walter
Tim Walter
TBTim Berger
Tim Berger
SKStoyan Kondov
Stoyan Kondov
RGRoman Gottardi
Roman Gottardi
JBJulia Benk
Julia Benk
MKMaximilian Kreibich
Maximilian Kreibich
Thoracic aortic emergencies involving the aortic arch are potentially fatal conditions that require the entire surgical repertoire of conventional surgery, such as complete aortic arch replacement using the frozen-elephant-trunk technique, through hybrid procedures, to full surgical endovascular options with conventional or delivered/fenestrated stent-grafts. An interdisciplinary aortic team should choose the optimal treatment of the pathologies of the aortic arch, considering the morphology of the entire aorta, from the root to beyond the bifurcation, as well as the clinical comorbidities. The treatment goal is a complication-free postoperative result and lasting freedom from aortic reinterventions. Irrespective of the selected therapy method, patients should then be connected to a specialized aortic outpatient clinic. The aim of this review was to provide an overview of pathophysiology and current treatment options in emergencies of the thoracic aorta, also involving the aortic arch. We wanted to summarize the preoperative considerations, intraoperative settings, and strategies, as well the postoperative follow-up.