Krzysztof Wróbel

Clinical outcome of arterial myocardial revascularization using bilateral internal thoracic arteries in diabetic patients: a single centre experience.

OBJECTIVES The use of bilateral internal thoracic arteries (BITAs) grafting has been documented to be advantageous over left internal thoracic artery (LITA) grafting. It has been shown to significantly improve clinical outcomes and increase long-term survival in patients with diabetes. However, harvesting BITAs may result in a greater risk of superficial wound infection (SWI) or deep sternal wound infection (DSWI) and cardiovascular complications (major adverse cardiac and cerebrovascular events; MACCE) in such a patient group. The objective of this study was to compare the incidence of SWI or DSWI and cardiovascular events in a series of isolated coronary artery bypass grafting (CABG) patients who underwent BITA grafting vs LITA grafting. METHODS A total of 147 patients with coronary artery disease and diabetes underwent isolated CABG at John Paul II Hospital. Of these, 38 procedures were performed using BITA grafting and 109 with LITA-saphenous vein grafting. RESULTS MACCE were similar in bilateral groups (7.9%--BITA group and 9.2%--LITA group). No significant difference was found in mortality and length of stay between bilateral groups. The MACCE risk factor was age. The incidence of SWI and DSWI and sternal re-fixation did not differ between the BITA or LITA groups (5.2 vs 9.1%, 5.2 vs 7.3% and 5.2 vs 6.4%). The risk factors for DSWI were age (odds ratio 3.47, P = 0.032 for every 10 years) and body mass index >30 kg/m(2). CONCLUSIONS Perioperative complications do not increase with the use of BITAs in this group of diabetic patients. There are no statistically significant differences in the number of superficial or deep wound infections or number of sternal resuturing between the BITA and LITA groups.

The dynamic cardiac biosimulator: A method for training physicians in beating-heart mitral valve repair procedures

Objective Previously, cardiac surgeons and cardiologists learned to operate new clinical devices for the first time in the operating room or catheterization laboratory. We describe a biosimulator that recapitulates normal heart valve physiology with associated real‐time hemodynamic performance. Methods To highlight the advantages of this simulation platform, transventricular extruded polytetrafluoroethylene artificial chordae were attached to repair flail or prolapsing mitral valve leaflets. Guidance for key repair steps was by 2‐dimensional/3‐dimensional echocardiography and simultaneous intracardiac videoscopy. Results Multiple surgeons have assessed the use of this biosimulator during artificial chordae implantations. This simulation platform recapitulates normal and pathologic mitral valve function with associated hemodynamic changes. Clinical situations were replicated in the simulator and echocardiography was used for navigation, followed by videoscopic confirmation. Conclusions This beating heart biosimulator reproduces prolapsing mitral leaflet pathology. It may be the ideal platform for surgeon and cardiologist training on many transcatheter and beating heart procedures.

Transapical off-pump mitral valve repair. First experience with the NeoChord system in Poland (report of two cases)

BACKGROUND Artificial chord implantation to repair a flail or prolapsing mitral valve leaflet requires open heart surgery and cardiopulmonary bypass. AIM Transapical off-pump artificial chordae implantation is a new surgical technique proposed to treat degenerative mitral valve regurgitation. The procedure is performed using the NeoChord DS1000 system (NeoChord, Inc., St. Louis Park, MN, USA), which facilitates both implantation and lenght adjustment of the artificial chordae under two (2D)- and three (3D)-dimensional transoesophageal echocardiographic (TEE) guidance on a beating heart. METHODS Two male patients aged 60 and 55 years with severe mitral regurgitation due to posterior leaflet prolapse underwent transapical off-pump artificial chordae implantation on September 3, 2015. The procedure was performed by left minithoracotomy under general anaesthesia in a cardiac surgical theatre, using 2D and 3D TEE guidance. RESULTS Early procedural success as confirmed by 3D TEE was achieved in both patients, with implantation of 6 artificial chordae in the first patient and 3 artificial chordae in the second patient. Both procedures were uneventful, and no postoperative complications were noted. The patients were discharged home on the 8th and 6th postoperative day, respectively. CONCLUSIONS The NeoChord DS1000 system allows both implantation and lenght adjustment of artificial chordae under 2D and 3D TEE guidance on a beating heart. Our initial experience in 2 patients with posterior mitral leaflet prolapse indicates that the procedure is feasible and safe.

Comparison of SVM and Ontology-Based Text Classification Methods

This work addresses the challenging task of text categorization. The main goal is the comparison of two different approaches, i.e. Vector Space Model and ontology-based solutions. The authors compare and contrast them with respect to accuracy and processing flow, which affect the classification results. The ontology-based method outperforms its counter-part when it comes to category resolution, i.e. the number of categories which can be processed. On the other hand, the SVM-based module is much faster and performs well when trained on an appropriately-structured learning set. The authors performed a series of tests to compare the methods and, as expected, the ontology-based solution outperformed the SVM classifier. It reached a micro averaged F1-score of 0.90 with 2.8 million Wikipedia articles, whereas the SVM-based module did not exceed 0.86 with the same data set. The macro averaged F1-score of both solutions was inferior to the micro one and reached values of 0.75 and 0.57, for ontology and SVM-based solutions respectively.

How to predict the risk of postoperative complications after coronary artery bypass grafting in patients under 50 and over 80 years old. A retrospective cross-sectional study

BACKGROUND Coronary artery disease (CAD) remains the leading cause of death in developed countries, and there is an increasing number of both young and elderly patients requiring surgical treatment. Despite improvement of conventional risk stratification scores (EuroSCORE II, STS risk score), all of the calculations are estimated based on the typical population and the studies emphasise that the scales may need further investigation and modernisation because demographic changes of the population suffering from CAD are unavoidable. AIM To characterise two increasing and challenging cohorts of patients undergoing coronary artery bypass grafting (CABG) and to identify preoperative risk factors for postoperative complications. METHODS In the retrospective cross-sectional study, we analysed 388 patients ≥ 80 years old and 190 patients ≤ 50 years old, who underwent CABG consecutively at our Institution. Data were obtained from medical records. RESULTS The vast majority of studied patients had commonly described risk factors for cardiovascular diseases, regardless of the age group. Diabetes was present in almost twice as many individuals in the older cohort, when compared to the EuroSCORE population. A similar observation was made for hypertension, which was more frequent in both age groups. Summarising all of the postoperative complications, at least one occurred significantly more frequently among the older group (10% vs. 20.9%, p = 0.001). The vast majority of major adverse cardiac and cerebrovascular events (MACCE) in the older group led to death (79.4%). Among patients ≥ 80 years old, higher New York Heart Association (NYHA) class (p = 0.001, OR 2.05 [1.34-3.12] for every next class) and renal failure (p = 0.02, OR 2.47 [1.16-5.25]) increased the MACCE rate, whereas higher left ven-tricular ejection fraction (LVEF) (p = 0.002, OR 0.81 [0.7-0.93] for every 5%) decreased the risk. Emergent admission was the only factor increasing the occurrence of any postoperative complications among patients ≤ 50 years old (p = 0.007, OR 3.63, 95% CI 1.37-9.62). On the other hand, among patients ≥ 80 years old, emergent admission was not associated with any postoperative complications. CONCLUSIONS Young and old patients requiring CABG differ from the standard EuroSCORE population. Postoperative complications are more common among older patients, and MACCE is usually fatal in this age group. Individuals with risk factors for MACCE (higher NYHA class, renal failure, lower LVEF) should be carefully evaluated and qualified, and closely monitored post-surgery.

Minimally invasive coronary artery bypass as a safe method of surgical revascularization. The step towards hybrid procedures

Introduction Coronary artery disease is nowadays responsible for approximately 15% of hospitalizations in Poland. Minimally invasive coronary artery bypass (MIDCAB) represents an attractive alternative to a sternotomy, and at the same time provides better life quality and facilitates quick rehabilitation. Aim To evaluate whether MIDCAB can be performed with similar early and mid-term results as off-pump coronary artery bypass (OPCAB) and therefore can be considered as a safe stage in hybrid revascularization. Material and methods In a retrospective cohort study, we analyzed 73 consecutive patients who underwent coronary artery bypass grafting (left internal mammary artery to left anterior descending artery) between 2013 and 2016 in the Department of Cardiovascular Surgery and Transplantology, John Paul II Hospital, Krakow. Thirty-eight (52.1%) MIDCAB and 35 (47.9%) OPCAB patients were enrolled. Results Short-term results did not significantly differ between groups and similar 30-day mortality was observed (MIDCAB 2.6% vs. OPCAB 2.9%, p = 1). The median follow-up period was 21 months. There were no statistical differences in terms of overall survival or cardiac mortality between groups (94.7% vs. 88.6%, p = 0.42; 2.6% vs. 2.9%, p = 1, respectively). The rate of hospitalization due to cardiac causes was similar in both groups (7.9% vs. 5.1%, p = 1) and there were no differences in current exacerbation of angina or heart failure, with median NYHA class I and CCS class I in both groups. Conclusions Despite higher technical difficulty, MIDCAB procedures can be performed with similar safety results as OPCAB procedures. No differences in terms of mortality, repeat revascularization or recurrent angina are observed.