Surgical and endovascular revascularization of chronic mesenteric ischemia.

PURPOSE: Chronic mesenteric ischemia (CMI) is a rare but life-threatening disease. This study reviewed outcomes in patients treated surgically for CMI by open treatment (OT) and endovascular treatment (ET), analyzing risk factors for endovascular failure. METHODS: Clinical data for 36 patients treated for CMI from 2007 to 2017 were retrospectively analyzed. The study's primary endpoint was symptom-free survival. The secondary endpoint was the primary technical success for endovascular and open surgical treatments. Risk factors for endovascular failure were identified by using univariate analysis. RESULTS: Patients were analyzed as treated: 21 patients (58.3%) in the ET and 15 (41.6%) in the OT group. Overall, 20 patients (56%) presented with abdominal angina, 9 (25%) with rest pain, and 7 (19%) without symptoms. An ET was initially attempted in 31 patients (86.1%). The conversion rate from ET to OT was 32.3%, which resulted in a primary technical success of 67.6% in ET and 100% in OT. Six patients from the ET group (19.3%) required surgical revision due to restenosis. One-year (OT 91.6% vs. ET 96.8%; n.s.) and three-year primary patency (OT 91.6% vs. ET 80.6%; n.s.) as well as 3-year symptom-free survival did not differ between the groups (OT 62.5% vs. ET 69.4%; n.s). Overall, in-hospital mortality was 2.8% (n = 1), which was not statistically different between the groups (OT 6% vs. ET 0%; n.s.). High-grade stenosis of the superior mesenteric artery tended to be associated with higher technical failure (P = 0.06). CONCLUSIONS: ET showed a comparable perioperative outcome with higher technical failure. OT was distinguished by excellent early and late technical success.

Management and outcome of true visceral and renal artery aneurysm repair.

PURPOSE: Visceral and renal artery aneurysms (VAA, RAA) are very rare pathologies. Both surgical and endovascular therapies are discussed as therapeutic options for ruptured and non-ruptured aneurysm repair; we describe our experience in the open and endovascular management of these entities. METHODS: Retrospective database analysis of 60 treated VAA and RAA in 59 patients between 1994 and 2020. Outcome data was descriptively analyzed. RESULTS: Thirty-seven aneurysms were surgically treated and 23 interventionally. In the total study cohort, we observed a mortality of 1.7% and a morbidity of 18.6%. One major complication occurred. The morbidity was higher after surgical repair in ruptured and non-ruptured cases. The mean aneurysm diameter was 30.5 ± 15.6 mm. Patients with hepatic or pancreaticoduodenal artery aneurysms presented more often in the stage of rupture, without differences in aneurysm size. The length of hospital stay after endovascular repair was significantly shorter compared to open surgical treatment (7.2 ± 6.9 days versus 11.8 ± 6.7 days, p = 0.014), but only in elective cases. Primary technical success was significantly better in patients that underwent surgical repair in an intention to treat analysis (100% versus 79.3%). The mean follow-up of the cohort was 53.5 months (range 3-207 months). CONCLUSION: Elective endovascular therapy and open surgery of VAA and RAA are safe procedures with a good periprocedural and long-term outcome. Surgical revascularization showed a better primary technical success but was associated with longer length of hospital stays.

[Open thoracic and thoracoabdominal aortic repair vs. f/bTEVAR - complementary or competitive?] / Offener thorakaler und thorakoabdominaler Aortenersatz vs. f/b(T)EVAR ­ komplementär oder kompetitiv?

The classical approach of open repair (OR) for thoracic and thoracoabdominal aortic pathologies, including aneurysms and dissection, has been outnumbered by the use of fenestrated/branched (thoracic) endovascular aortic repair (f/b[T]EVAR) in recent years. Providing OR for complex cases in an aortic service requires a dedicated surgical setup and a huge body of expertise in this particular field.In order to reduce specific complications, such as perioperative mortality, kidney failure, spinal cord ischemia, stroke or bowel ischemia, it is necessary to apply cerebrospinal-spinal fluid drainage, point-of-care coagulation therapy, distal and retrograde aortic perfusion and sequential clamping. Despite the predominance of endovascular solutions, the specific OR expertise is still needed for specific indications, such as young patients, connective tissue disorder or aortic graft infections.Currently, the short and mid term results for f/b(T)EVAR outweigh those for OR, including the shorter hospital stay and less invasive procedures. However, OR provides better long-term results for overall mortality, re-intervention rates and secondary complications.In conclusion, in our opinion OR is a service that is still necessary for dedicated aortic centres, but will most likely become more frequent again in the years to come.

Favorable outcome of experimental islet xenotransplantation without immunosuppression in a nonhuman primate model of diabetes.

Transplantation of pancreatic islets for treating type 1 diabetes is restricted to patients with critical metabolic lability resulting from the need for immunosuppression and the shortage of donor organs. To overcome these barriers, we developed a strategy to macroencapsulate islets from different sources that allow their survival and function without immunosuppression. Here we report successful and safe transplantation of porcine islets with a bioartificial pancreas device in diabetic primates without any immune suppression. This strategy should lead to pioneering clinical trials with xenotransplantation for treatment of diabetes and, thereby, represents a previously unidentified approach to efficient cell replacement for a broad spectrum of endocrine disorders and other organ dysfunctions.

Microscopic origin of the '0.7-anomaly' in quantum point contacts.

Quantum point contacts are narrow, one-dimensional constrictions usually patterned in a two-dimensional electron system, for example by applying voltages to local gates. The linear conductance of a point contact, when measured as function of its channel width, is quantized in units of GQ = 2e(2)/h, where e is the electron charge and h is Planck's constant. However, the conductance also has an unexpected shoulder at ∼0.7GQ, known as the '0.7-anomaly', whose origin is still subject to debate. Proposed theoretical explanations have invoked spontaneous spin polarization, ferromagnetic spin coupling, the formation of a quasi-bound state leading to the Kondo effect, Wigner crystallization and various treatments of inelastic scattering. However, explicit calculations that fully reproduce the various experimental observations in the regime of the 0.7-anomaly, including the zero-bias peak that typically accompanies it, are still lacking. Here we offer a detailed microscopic explanation for both the 0.7-anomaly and the zero-bias peak: their common origin is a smeared van Hove singularity in the local density of states at the bottom of the lowest one-dimensional subband of the point contact, which causes an anomalous enhancement in the Hartree potential barrier, the magnetic spin susceptibility and the inelastic scattering rate. We find good qualitative agreement between theoretical calculations and experimental results on the dependence of the conductance on gate voltage, magnetic field, temperature, source-drain voltage (including the zero-bias peak) and interaction strength. We also clarify how the low-energy scale governing the 0.7-anomaly depends on gate voltage and interactions. For low energies, we predict and observe Fermi-liquid behaviour similar to that associated with the Kondo effect in quantum dots. At high energies, however, the similarities between the 0.7-anomaly and the Kondo effect end.

Effects of regional anesthesia techniques on local anesthetic plasma levels and complications in carotid surgery: a randomized controlled pilot trial.

BACKGROUND: The ultrasound guided intermediate cervical plexus block with perivascular infiltration of the internal carotid artery (PVB) is a new technique for regional anesthesia in carotid endarterectomy (CEA). We conducted a pilot study investigating the effects of deep cervical block (DCB), intermediate cervical block alone (ICB) and PVB on perioperative complications in patients undergoing elective CEA. We hypothesized, that the ropivacaine plasma concentration is higher in patients receiving DCB compared to PVB and ICB. METHODS: In a randomized controlled pilot study thirty patients scheduled for elective CEA were randomly assigned into three groups: DCB receiving 20 mL ropivacaine 0.5% (n = 10), ICB receiving 20 mL ropivacaine 0.5% (n = 10) and PVB receiving 20 mL ropivacaine 0.5% and 10 mL ropivacaine 0,3% (n = 10). As primary outcome, plasma levels of ropivacaine were measured with high performance liquid chromatography before, 5, 10, 20, 60, and 180 min after the injection of ropivacaine. Secondary outcomes were vascular and neurological complications as well as patients' and surgeons' satisfaction. All analyses were performed on an intention-to-treat basis. Statistical significance was accepted at p < 0.05. RESULTS: No conversion to general anesthesia was necessary and we observed no signs of local anesthetic intoxication or accidental vascular puncture. Plasma concentration of ropivacaine was significantly higher in the DCB group compared to PVB and ICB (p < 0.001) and in the PVB group compared to ICB (p = 0.008). Surgeons' satisfaction was higher in the PVB group compared to ICB (p = 0.003) and patients' satisfaction was higher in the PVB group compared to ICB (p = 0.010) and DCB group (p = 0.029). Phrenic nerve paralysis was observed frequently in the DCB group (p < 0.05). None of these patients with hemi-diaphragmatic paralysis showed signs of respiratory distress. CONCLUSION: The ultrasound guided PVB is a safe and effective technique for CEA which is associated with lower plasma levels of local anesthetic than the standard DCB. Considering the low rate of complications in all types of regional anesthesia for CEA, larger randomized controlled trials are warranted to assess potential side effects among the blocks. TRIAL REGISTRATION: The trial was registered at German Clinical Trials Register (DRKS) on 04/05/2019 (DRKS00016705, retrospectively registered).

Production of high-quality islets from goettingen minipigs: Choice of organ preservation solution, donor pool, and optimal cold ischemia time.

BACKGROUND: The transplantation of porcine islets into man might soon become reality for patients with type 1 diabetes mellitus. Therefore, porcine islets of high quality and quantity, and a scalable isolation process with strict quality control will be an unconditional prerequisite to enable the best possible transplantation graft. In this study, we provide a comparative study evaluating islet isolation outcome and in vitro survival based upon donor age, organ preservation solution (OPS), and cold ischemia time (CIT). METHODS: Goettingen minipigs of younger age (1 year) and retired breeder animals (3.5 years) were studied. Pancreata were harvested according to the standards of human organ retrieval including in situ cold perfusion with either Custodiol® -HTK or Belzer® UW solution. Pancreatic tissue was characterized by quantification of apoptotic cells. Islet isolations were performed according to a modified Ricordi method, and isolation outcome was assessed by determining islet particle numbers (IP), islet equivalents (IEQ), and isolation factor (IF). Isolated islets were cultured for 24 and 48 h for the assessment of in vitro survival. RESULTS: Islet viability was significantly higher in Custodiol® -HTK preserved pancreas organs compared to Belzer® UW. Furthermore, organs harvested from retired breeder preserved in Custodiol® -HTK resulted in stable islet isolation yields even after prolonged CIT and showed superior survival rates of islets in vitro compared to the Belzer® UW group. Younger porcine donor organs resulted generally in lower islet yield and survival rates. CONCLUSIONS: In summary, Custodiol® -HTK solution should be preferred over Belzer® UW solution for the preservation of pancreata from porcine origin. Custodiol® -HTK allows for maintaining islet viability and promotes reproducible isolation outcome and survival even after longer CIT. The usage of retired breeder animals over young animals for islet isolation is highly advisable to yield high quality and quantity.

Predictive factors for better bypass patency and limb salvage after prosthetic above-knee bypass reconstruction.

BACKGROUND: Peripheral arterial disease (PAD) is one of the most underestimated diseases because of its high prevalence and unfavorable prognosis. Many PAD patients without suitable autologous veins or options for endovascular treatment receive prosthetic above-knee femoropopliteal bypass (PAKB). Until now predictors of prosthetic bypass failure and of increased amputation risk remain indistinct. This study aimed to identify predictive factors associated with better bypass patency and limb salvage to achieve a more favorable outcome after PAKB reconstruction. METHODS: Pre-, intra-, and postoperative data of 244 PAKB procedures performed at a German university medical center were collected and analyzed using univariate and multivariate methods. To our knowledge this 12-year experience is the largest retrospective study to identify predictors for patency and limb salvage after PAKB reconstruction. RESULTS: Of the PAD patients 94% (229/244) were followed for an average of 34.9 months. Patient cohorts characteristics were: mean age, 66.1 years, 181 men (74%), claudication (64%), rest pain (16%), ischemic lesions (20%), arterial hypertension (92%), smoking (79%), hyperlipidemia (65%) and type 2 diabetes (43%). Cumulative primary 1- and 3-year graft patency rates were 60.8% and 50.7%, respectively, and cumulative 1- and 3-year limb salvage rates were 89.3% and 86.1%, respectively. One hundred seven bypasses (43.9%) failed, 26 patients (10.7%) required a major and seven patients (2.9%) required a minor amputation. Overall survival rates of PAD patients after 1- and 3-years were 94.4% and 82.9%, respectively. Subjective symptom improvement was found to be the most important prognostic follow-up factor for graft patency and limb salvage. Patients with recurrent symptoms in the follow-up had an increased risk of emerging bypass failure compared with patients with subjective symptom improvement (patency at 1 year: 40.8% vs 100% and at 3 years: 26% vs 100%; P < .001). No patient with subjective improvement in symptoms during follow-up underwent an amputation (limb salvage at 1 year: 100% vs 79% and at 3 years: 100% vs 72.8%; P < .001). Therefore, subjective symptom improvement should be the decisive criterion to determine follow-up intervals of PAD patients. In univariate analysis further significant factors associated with better graft patency and limb salvage rates were: claudication compared with critical ischemia, larger graft diameter (>6 mm), pre- and postoperative antiplatelet therapy, statin therapy independent from lipid values after PAKB revascularization, and an experienced vascular surgeon. CONCLUSIONS: In our study, we determined the subjective improvement in symptoms as the most important prognostic factor for bypass function and limb salvage after PAKB. Furthermore, disease stage of critical ischemia, graft diameter, preoperative aspirin use, and postoperative statin medication were independent predictive factors. Therefore, PAD patients should be treated with aspirin pre- and postoperatively as well as with a statin postoperatively. In case of PAKB reconstruction only prostheses with a large diameter (>6 mm) should be used and the procedure should be performed by an experienced surgeon. Considering these results with regard to the predictive factors for better graft patency and limb salvage rates a significant more favorable outcome during the follow-up and an increased 5-year patency rate for PAKB reconstructions can be expected.

Islet cell transplantation from Göttingen minipigs to cynomolgus monkeys: analysis of virus safety.

BACKGROUND: Xenotransplantation using pig cells, tissues or organs may be associated with the transmission of porcine zoonotic micro-organisms. Hepatitis E virus (HEV), porcine cytomegalovirus (PCMV) and porcine endogenous retroviruses (PERVs) are potentially zoonotic micro-organisms which do not show clinical symptoms in pigs and which are due to the low expression level difficult to detect. Göttingen Minipigs (GöMP) are often used for biomedical investigations and they are well characterized concerning the presence of numerous bacteria, fungi, viruses and parasites and therefore may be used for islet cell transplantation. METHODS: Islet cells derived from three GöMP were transplanted into four healthy, non-diabetic cynomolgus monkeys using a macroencapsulation device. PCR, nested PCR, real-time PCR, real-time RT-PCR and Western blot analyses were used to estimate the presence of PERV, PCMV and HEV in the donors and recipients. RESULTS: Using sensitive detection methods, no HEV was found in the donor pigs and in the pig islet cell preparations. Antibodies against PERV, PCMV and HEV were not found in all cynomolgus monkeys with exception of one monkey showing an immune response against HEV. Using real-time PCR, no PCMV and HEV were found in the sera of all monkeys. CONCLUSION: Although the donor islet cells and the recipients were negative for HEV using PCR and Western blot analysis, in one recipient, antibodies against HEV were found, indicating infection in a single case. All recipients were negative for antibodies against PERV, and all were negative for PCMV, indicating absence of infection. As HEV was not detected in the donor pig before transplantation, a more complex and regular screening of the animals using highly sensitive methods is required to avoid virus transmission.

Diabetes induction by total pancreatectomy in minipigs with simultaneous splenectomy: a feasible approach for advanced diabetes research.

BACKGROUND: Safe and reliable diabetes models are a key prerequisite for advanced preclinical studies on diabetes. Chemical induction is the standard model of diabetes in rodents and also widely used in large animal models of non-human primates and minipigs. However, uncertain efficacy, the potential of beta-cell regeneration, and relevant side effects are debatable aspects particularly in large animals. Therefore, we aimed to evaluate a surgical approach of total pancreatectomy combined with splenectomy for diabetes induction in an exploratory study in Goettingen minipigs. METHODS: Total pancreatectomy was performed in Goettingen minipigs (n = 4) under general anesthesia and endotracheal intubation. Prior to surgery, a central venous line was established for drug application and blood sampling. After median laparotomy, splenectomy was performed and the lobular pancreas was carefully dissected with particular attention to the duodenal vascular arcade. Close monitoring of blood glucose was initiated immediately after surgery by standard glucometer measurement or continuous glucose monitoring systems (CGMS). Exogenous insulin was given by multiple daily subcutaneous (s.c.) injections or via insulin pump systems (CSII). Complete endogenous insulin deficiency was confirmed by intravenous glucose tolerance test (ivGTT) and measurement of c-peptide. For establishing a suitable regimen for diabetes management, the animals were followed for 4-6 weeks. RESULTS: Following pancreatectomy and splenectomy, the animals showed a quick recovery from surgery and initial analgetic medication and volume substitution could be terminated within 24 h. A rapid increase in blood glucose was observed immediately following pancreatectomy necessitating insulin therapy. The induced exocrine insufficiency did not cause any clinical symptoms. Complete insulin deficiency could be confirmed in all animals by determination of negative c-peptide during glucose challenge. The two regimen of insulin treatment (multiple daily injections (MDI) and continuous subcutaneous insulin infusion (CSII)) were both feasible with respect to acceptable glycemic control whereas CSII was considerably advantageous in comfort and popularity for both animals and care takers. CONCLUSIONS: Surgical pancreatectomy in combination with splenectomy to facilitate access to the pancreas is a feasible model for efficient diabetes induction in minipigs. The procedure itself and postoperative animal care could be performed without complications in this exploratory study. Nevertheless, this approach requires well-equipped infrastructure, experienced and skilled surgeons and anesthesiologists and dedicated animal care takers. The impact of total pancreatectomy in combination with splenectomy on the digestive and immune system must be considered in the design and definition of end points of experimental diabetes and transplantation studies.

Automatic Classification of Marine Mammals with Speaker Classification Methods.

We present an automatic acoustic classifier for marine mammals based on human speaker classification methods as an element of a passive acoustic monitoring (PAM) tool. This work is part of the Protection of Marine Mammals (PoMM) project under the framework of the European Defense Agency (EDA) and joined by the Research Department for Underwater Acoustics and Geophysics (FWG), Bundeswehr Technical Centre (WTD 71) and Kiel University. The automatic classification should support sonar operators in the risk mitigation process before and during sonar exercises with a reliable automatic classification result.

Comparison of PAM Systems for Acoustic Monitoring and Further Risk Mitigation Application.

We present results of the SIRENA 2011 research cruises conducted by the NATO Undersea Research Centre (NURC) and joined by the Research Department for Underwater Acoustics and Geophysics (FWG), Bundeswehr Technical Centre (WTD 71) and the Universities of Kiel and Pavia. The cruises were carried out in the Ligurian Sea. The main aim of the FWG was to test and evaluate the newly developed towed hydrophone array as a passive acoustic monitoring (PAM) tool for risk mitigation applications. The system was compared with the PAM equipment used by the other participating institutions. Recorded sounds were used to improve an automatic acoustic classifier for marine mammals, and validated acoustic detections by observers were compared with the results of the classifier.

Protection of Marine Mammals.

Within the European Defense Agency (EDA), the Protection of Marine Mammals (PoMM) project, a comprehensive common marine mammal database essential for risk mitigation tools, was established. The database, built on an extensive dataset collection with the focus on areas of operational interest for European navies, consists of annual and seasonal distribution and density maps, random and systematic sightings, an encyclopedia providing knowledge on the characteristics of 126 marine mammal species, data on marine mammal protection areas, and audio information including numerous examples of various vocalizations. Special investigations on marine mammal acoustics were carried out to improve the detection and classification capabilities.

Transplantation of human islets without immunosuppression.

Transplantation of pancreatic islets is emerging as a successful treatment for type-1 diabetes. Its current stringent restriction to patients with critical metabolic lability is justified by the long-term need for immunosuppression and a persistent shortage of donor organs. We developed an oxygenated chamber system composed of immune-isolating alginate and polymembrane covers that allows for survival and function of islets without immunosuppression. A patient with type-1 diabetes received a transplanted chamber and was followed for 10 mo. Persistent graft function in this chamber system was demonstrated, with regulated insulin secretion and preservation of islet morphology and function without any immunosuppressive therapy. This approach may allow for future widespread application of cell-based therapies.

Lissajous Rocking Ratchet: Realization in a Semiconductor Quantum Dot.

Breaking time-reversal symmetry (TRS) in the absence of a net bias can give rise to directed steady-state nonequilibrium transport phenomena such as ratchet effects. Here we present, theoretically and experimentally, the concept of a Lissajous rocking ratchet based on breaking TRS. Our system is a semiconductor quantum dot with periodically modulated dot-lead tunnel barriers. Broken TRS gives rise to single electron tunneling current. Its direction is fully controlled by exploring frequency and phase relations between the two barrier modulations. The concept of Lissajous ratchets can be realized in a large variety of different systems, including nanoelectrical, nanoelectromechanical, or superconducting circuits. It promises applications based on a detailed on-chip comparison of radio-frequency signals.

Transplantable bioartificial pancreas devices: current status and future prospects.

BACKGROUND: Islet transplantation has become a valuable therapy for patients with diabetes mellitus type 1.However, only selected patients with exhausted insulin therapy characterized by instable metabolic control and repeated severe hypoglycemia are transplant candidates. This strict indication is mainly due to the requirement for lifelong immunosuppression and the critical shortage for donor organs. Therefore, numerous research activities address these issues in order to provide beta cell replacement therapy to a broader cohort of patients with diabetes. METHODS: The encapsulation of pancreatic islets within mainly alginate-based macro- or microcapsules withvarious physical configurations may allow protecting the islet graft without the need for immunosuppressive agents and moreover expanding the donor pool to animal tissue and novel insulin-producing cells. Despite major advances in encapsulation technology, a significant translation into clinical application is not evident. There are still issues that need to be resolved associated with graft oxygenation, immunprotection, inflammatory response, material biocompatibility, and transplantation site to list some of them. CONCLUSION: The recent advances in xenotransplantation and particularly in the field of stem cell-derived beta cells have generated a renewed scientific interest in encapsulation. This review aims to provide an overview on current encapsulation technologies as a treatment modality in cell replacement therapy for type 1 diabetes.

Improvement of islet function in a bioartificial pancreas by enhanced oxygen supply and growth hormone releasing hormone agonist.

Islet transplantation is a feasible therapeutic alternative for metabolically labile patients with type 1 diabetes. The primary therapeutic target is stable glycemic control and prevention of complications associated with diabetes by reconstitution of endogenous insulin secretion. However, critical shortage of donor organs, gradual loss in graft function over time, and chronic need for immunosuppression limit the indication for islet transplantation to a small group of patients. Here we present a promising approach to address these limitations by utilization of a macrochamber specially engineered for islet transplantation. The s.c. implantable device allows for controlled and adequate oxygen supply and provides immunological protection of donor islets against the host immune system. The minimally invasive implantable chamber normalized blood glucose in streptozotocin-induced diabetic rodents for up to 3 mo. Sufficient graft function depended on oxygen supply. Pretreatment with the growth hormone-releasing hormone (GHRH) agonist, JI-36, significantly enhanced graft function by improving glucose tolerance and increasing ß-cell insulin reserve in rats thereby allowing for a reduction of the islet mass required for metabolic control. As a result of hypervascularization of the tissue surrounding the device, no relevant delay in insulin response to glucose changes has been observed. Consequently, this system opens up a fundamental strategy for therapy of diabetes and may provide a promising avenue for future approaches to xenotransplantation.

Large nuclear spin polarization in gate-defined quantum dots using a single-domain nanomagnet.

The electron-nuclei (hyperfine) interaction is central to spin qubits in solid state systems. It can be a severe decoherence source but also allows dynamic access to the nuclear spin states. We study a double quantum dot exposed to an on-chip single-domain nanomagnet and show that its inhomogeneous magnetic field crucially modifies the complex nuclear spin dynamics such that the Overhauser field tends to compensate external magnetic fields. This turns out to be beneficial for polarizing the nuclear spin ensemble. We reach a nuclear spin polarization of ≃50%, unrivaled in lateral dots, and explain our manipulation technique using a comprehensive rate equation model.

How to asses and improve cardiopulmonary risk prior to vascular surgery?

Patients with peripheral arterial disease have a high rate of cardiac, cerebrovascular, or pulmonary comorbidities. Peripheral arterial surgical interventions are associated with a moderate to high perioperative cardiac risk. Simple clinical scoring systems for preoperative risk stratification can be used to identify high-risk patients. In these patients further diagnostic and therapeutic measures are required to reduce perioperative morbidity and mortality. In contrast, a group of patients can be identifed that do not require additional cardiopulmonary diagnostics and can immediately proceed to the intervention. According to evidence-based recommendations in patients at risk beta blocker should be uptitrated and statin therapy should be initiated preoperatively. Quitting smoking preoperatively also reduces perioperative complications and should be encouraged in all patients.