Determination of selective antegrade perfusion flow rate in aortic arch surgery to restore baseline cerebral near-infrared spectroscopy values: a single-centre observational study.

OBJECTIVES: Neuroprotection during aortic arch surgery involves selective antegrade cerebral perfusion. The parameters of cerebral perfusion, e.g. flow rate, are inconsistent across centres and are subject of debate. The aim of this study was to determine the cerebral perfusion flow rate during hypothermic circulatory arrest required to meet preoperative awake baseline regional cerebral oxygen saturation (rSO2). METHODS: Patients scheduled for aortic arch surgery with hypothermic circulatory arrest were enrolled in this prospective observational study. After initiation of hypothermic circulatory arrest, bilateral selective antegrade cerebral perfusion was established and cerebral flow rate was continuously increased. The primary end point was the difference of cerebral saturation from baseline during cerebral perfusion flow rates of 6, 8 and 10 ml/kg/min. RESULTS: A total of 40 patients were included. During antegrade cerebral perfusion, rSO2 was significantly lower than the baseline at 6 ml/kg/min [-7.3, 95% confidence interval (CI): -1.7, -12.9; P = 0.0015]. In contrast, flow rates of 8 and 10 ml/kg/min resulted in rSO2 that did not significantly differ from the baseline (-2; 95% CI: -4.3, 8.3; P > 0.99 and 1.8; 95% CI: -8.5%, 4.8%; P > 0.99). Cerebral saturation was significantly more likely to meet baseline values during selective antegrade cerebral perfusion with 8 ml/kg/min than at 6 ml/kg/min (44.1%; 95% CI: 27.4%, 60.8% vs 11.8%; 95% CI: 0.9%, 22.6%; P = 0.0001). CONCLUSIONS: At 8 ml/kg/min cerebral flow rate during selective antegrade cerebral perfusion, regional cerebral oximetry baseline values are significantly more likely to be achieved than at 6 ml/kg/min. Further increasing the cerebral flow rate to 10 ml/kg/min does not significantly improve rSO2.

Efficacy and Safety of Heparinization before Deployment of Endograft for Blunt Traumatic Aortic Injury in Severely Injured Patients.

BACKGROUND: The administration of unfractionated heparin (UFH) during endovascular repair of blunt traumatic aortic injury (BTAI) is controversial. The aim of the study is to report the early outcomes of patients undergoing thoracic endovascular aortic repair (TEVAR) for BTAI, and to assess the individualized intraoperative use and dose of UFH. METHODS: This is a retrospective analysis including consecutive patients treated with TEVAR for BTAI of the descending aorta between January 1st, 2005 and December 31st, 2018. Intraoperative use and doses of UFH were analyzed. Primary outcome included a reintervention because of new onset bleeding and/or thromboembolic complication and 30-day mortality. Technical success, injury severity score (ISS), timing of treatment, and neurologic deterioration were secondary outcome. RESULTS: Thirty-six patients with a mean age of 47 ± 18 years, 30 males (83%), were included. Intraoperative administration of UFH was recorded in 30/36 patients (83%) with a mean dose of 4750 ± 2180 IU. Two patients had no UFH because of extensive intracranial hemorrhage or suspected relevant liver laceration, respectively; 1 died in theatre, 1 was already anticoagulated having a mechanical aortic valve, and in 2 no information about heparin use was found. During 30 days of follow-up, 3 patients died (8%; 3/36): 1 patient with completely transected aorta died on-table and 2 on the fifth postoperative day, 1 from trauma-associated brain injury and 1 with multi organ failure. No bleeding or thromboembolic complication requiring reintervention occurred in any patient during 30 days follow-up. In 3 patients partial unintentional coverage of the left common carotid artery occurred, resulting in technical success of 89% (32/36). Mean ISS was 43 ± 15. Thirty-five patients (97%) were severely injured having an ISS ≥ 25. Twenty-nine patients (81%) were treated within 24 hr and 6 patients (17%) within 1 week. No stroke or spinal cord ischemia was observed. CONCLUSIONS: Systemic heparinization in different doses during TEVAR for BTAI can be safe with no intraoperative bleeding or thromboembolic complications in early postoperative period.

[Traumatic aortic rupture - diagnosis and managment]. / Die traumatische Aortenruptur.

Road traffic accidents are the main cause of traumatic aortic ruptures, mostly in combination with other severe injuries. The pre-hospital mortality rate is high. Suspected aortic trauma, following a high traumatic aortic injury score, is an indication for computer tomography. Injuries are triaged and the treatment priority of the aortic trauma is ascertained based on the severity of the aortic and concomitant injuries and the condition of the patient. Until definitive treatment of the aortic lesion is completed, the blood pressure of the patient must be kept low. Grade I and II lesions can be managed under strict monitoring with initial conservative treatment in individual cases. Grade III (contained perforation) and grade IV (open rupture) lesions need surgical or interventional treatment as swiftly as possible. In selected cases, a delayed treatment can also be advantageous.The endovascular stent graft therapy has established itself as the preferred form of treatment.

Prevalence and Evolution of Susceptibility-Weighted Imaging Lesions in Patients With Artificial Heart Valves.

Background In patients with mechanical heart valves, cerebral susceptibility-weighted imaging (SWI) lesions on magnetic resonance imaging, postulated to be caused by degenerative metallic abrasion, are frequently referred to as valve abrasion. It remains unclear whether valve implantation not requiring cardiopulmonary bypass or biological heart valves also shows those lesions. Methods and Results Two blinded readers rated SWI lesions and cerebral amyloid angiopathy probability according to established criteria on brain magnetic resonance imaging pre- and postinterventionally. We assessed the association between valve type/cardiopulmonary bypass use and SWI lesion count on the first postinterventional scan using multivariable logistic regression. On postinterventional magnetic resonance imaging, 57/58 (98%) patients with mechanical heart valves had at least 1 and 46/58 (79%) 3 or more SWI lesions, while 92/97 (95%) patients with biological heart valves had at least 1 and 72/97 (74%) 3 or more SWI lesions. On multivariate analysis, duration of cardiopulmonary bypass during implantation significantly increased the odds of having SWI lesions on the first postinterventional magnetic resonance imaging (ß per 10 minutes 0.498; 95% CI, 0.116-0.880; P=0.011), whereas valve type showed no significant association (P=0.338). Thirty-seven of 155 (23.9%) patients fulfilled the criteria of possible/probable cerebral amyloid angiopathy. Conclusions SWI lesions in patients with artificial heart valves evolve around the time point of valve implantation and the majority of patients had multiple lesions. The missing association with the valve type weakens the hypothesis of degenerative metallic abrasion and highlights cardiopulmonary bypass as the main risk factor for SWI occurrence. SWI lesions associated with cardiac procedures can mimic cerebral amyloid angiopathy. Further research needs to clarify whether those lesions are associated with intracranial hemorrhage after intravenous thrombolysis or anticoagulation.

Symptomatic or aneurysmal aberrant subclavian arteries: results of surgical and hybrid repair.

OBJECTIVES: Indications and techniques of repair for symptomatic or aneurysmal aberrant subclavian arteries (ASA) are controversial. This study analyses presentation, treatment and outcome of patients with symptomatic and/or aneurysmal ASA. METHODS: Retrospective analysis of consecutive adult patients undergoing symptomatic and/or aneurysmal ASA repair between January 2000 and June 2016. RESULTS: Of 12 patients (4 females) with a median age of 66 years (range 24-75), 10 had right ASA and 2 had left ASA originating from a right aortic arch. Six patients (50%) had Kommerell's diverticulum and 6 patients had aneurysmal dilatation of the ASA itself. Six patients presented with symptoms (dysphagia n = 4, chest pain n = 1, recurrent aspiration n = 1). Nine patients (75%) were treated by open ASA resection/ligation with or without aortic repair. Three patients (25%) underwent hybrid repair using thoracic endovascular aortic repair to exclude the aberrant artery. ASA revascularization was achieved by subclavian-carotid transposition (n = 7), carotid-subclavian bypass (n = 1), aorto-subclavian bypass (n = 3) or reimplantation after aortic graft replacement (n = 1). Thirty-day mortality was 8% (n = 1). The median follow-up duration was 44 months (range 24-151). Symptoms were relieved in 4 and persisted partially in 1, while symptom relief remained unknown in 1 patient who died during follow-up. Imaging after a median of 34 months (range 2-134) after the operation showed patent ASA revascularization in all patients and no endoleaks in the hybrid group. CONCLUSIONS: Surgical and hybrid repair allows satisfying results in patients with symptomatic and/or aneurysmal ASA. The optimal procedure has to be defined on an individual patient basis. Further studies, preferably with a multicentre approach, are required to answer more specific questions on the management of these patients and especially to assess long-term results following hybrid repair.

Impact of new technologies and experience on procedural aspects of surgical aortic valve replacement - a process analysis.

BACKGROUND: Surgical aortic valve replacement (SAVR) is the treatment of choice in severe symptomatic aortic valve disease. New techniques and prostheses have been recently developed to facilitate the procedure and reduce aortic cross-clamp time (AOx). The aim of this study was to analyse the different procedural steps in order to identify the most time-consuming part during aortic clamping time and to compare impact of experience on procedural aspects. METHODS: AOx during SAVR was divided into five consecutive steps. Duration of each step was measured. The first procedural step started with clamping of the aorta and ended with the beginning of the second step starting with the resection of the native aortic valve. The third step started with placement of the first valve anchoring suture, the fourth step started with tying of the first suture and the fifth and final step started after the cut of the last suture and ended with removal of the aortic clamp. Surgeons were divided into two groups based on their experience, which in our analysis was defined as a total SAVR experience of more than 100 procedures. RESULTS: From March 2013 to August 2015 57 nonconsecutive patients (33% female; age, median 71.0 years, interquartile range 65.0-76.0) undergoing isolated SAVR for severe aortic valve stenosis in our institution were included in this process analysis. Two different prostheses were implanted. Forty-eight (84%) patients received a tissue valve (Perimount Magna Ease, Edwards Lifesciences, Irvine, USA) and 9 (16%) patients received a mechanical prosthesis (Medtronic AP 360, St-Paul, MN, USA). The mean estimated risk of mortality was 1.1% (0.7-1.6) according to the logistic EUROScore II. Overall duration of AOx was 50.5 ± 13.8 min, with 32.3% (16.4 ± 5.9 min) accounting for placing the sutures into the native annulus and the prosthetic sewing ring and 18.5% (9.2 ± 3.0min) accounting for tying and cutting the sutures. Surgeons with more experience performed 35 operations (61.4%) and needed an average of 44.1 ± 11.5 min versus 60.6 ± 11.0 min (p <0.001) for less experienced surgeons. Surgeons with more experience needed 14.0 ± 5.0 min for the suturing step and 8.4 ± 2.8 min for tying the sutures compared with 20.2 ± 5.2 min and 10.5 ± 3.0 min, respectively, for the less experienced surgeons with (p <0.001 and p = 0.010). CONCLUSION: Placing and tying sutures in the prostheses accounts for over half (50.8%) of AOx during isolated SAVR. Experienced surgeons have significantly reduced AOx. This shortening is equally distributed between all five procedural steps.

Graft preservation solutions in cardiovascular surgery.

Vein grafts are still the most commonly used graft material in cardiovascular surgery and much effort has been spent in recent years on investigating the optimal harvesting technique. One other related topic of similar importance remained more or less an incidental one. The storage solutions of vein grafts following procurement and prior to implantation are, despite their assumed impact, a relatively neglected theme. There is no doubt that the endothelium plays a key role in long-term patency of vein grafts, but the effects of the different storage solutions on the endothelium remain unclear : In a review of the literature, we could find 20 specific papers that addressed the question, of which the currently available preservation solutions are superior, harmless, damaging or ineffective. The focus lies on saline and autologous whole blood. Besides these two storage media, novel or alternative solutions have been investigated with surprising findings. In addition, a few words will be spent on potential alternatives and novel solutions on the market. As there is currently no randomized clinical trial regarding saline versus autologous whole blood available, this review compares all previous studies and methods of analysis to provide a certain level of evidence on this topic. In summary, saline has negative effects on the endothelial layers and therefore may compromise graft patency. Related factors, such as distension pressure, may outbalance the initial benefit of autologous whole blood or storage solutions and intensify the harmful effects of warm saline. In addition, there is no uniform consent on the superiority of autologous whole blood for vein graft storage. This may open the door to alternatives such as the University of Wisconsin solution or one of the specific designed storage solutions like TiProtec™ or Somaluthion™. Whether these preservation solutions are superior or advantageous remains the subject of further studies.

Minimized extracorporeal circulation does not impair cognitive brain function after coronary artery bypass grafting.

OBJECTIVES: Objective evaluation of the impact of minimized extracorporeal circulation (MECC) on perioperative cognitive brain function in coronary artery bypass grafting (CABG) by electroencephalogram P300 wave event-related potentials and number connection test (NCT) as metrics of cognitive function. METHODS: Cognitive brain function was assessed in 31 patients in 2013 with a mean age of 65 years [standard deviation (SD) 10] undergoing CABG by the use of MECC with P300 auditory evoked potentials (peak latencies in milliseconds) directly prior to intervention, 7 days after and 3 months later. Number connection test, serving as method of control, was performed simultaneously in all patients. RESULTS: Seven days following CABG, cognitive P300 evoked potentials were comparable with preoperative baseline values [vertex (Cz) 376 (SD 11) ms vs 378 (18) ms, P = 0.39; frontal (Fz) 377 (11) vs 379 (21) ms, P = 0.53]. Cognitive brain function at 3 months was compared with baseline values [(Cz) 376 (11) ms vs 371 (14 ms) P = 0.09; (Fz) 377 (11) ms vs 371 (15) ms, P = 0.04]. Between the first postoperative measurement and 3 months later, significant improvement was observed [(Cz) 378 (18) ms vs 371 (14) ms, P = 0.03; (Fz) 379 (21) vs 371 (15) ms, P = 0.02]. Similar clearly corresponding patterns could be obtained via the number connection test. Results could be confirmed in repeated measures analysis of variance for Cz (P = 0.05) and (Fz) results (P = 0.04). CONCLUSIONS: MECC does not adversely affect cognitive brain function after CABG. Additionally, these patients experience a substantial significant cognitive improvement after 3 months, evidentiary proving that the concept of MECC ensures safety and outcome in terms of brain function.

Double arterial perfusion strategy for extensive thoracic aortic surgery to avoid lower body hypothermic circulatory arrest.

OBJECTIVE: To analyse our results of using a double arterial perfusion strategy to avoid lower body hypothermic circulatory arrest after extensive thoracic aortic surgery. METHODS: We analysed the intra- and perioperative courses of 10 patients (median age 58 years, median logistic EuroSCORE 14.6) who underwent extensive thoracic aortic surgery with a double arterial perfusion strategy. The main goal of double arterial perfusion is to separate myocardial and supra-aortic from systemic perfusion. Aortic repair starts at the most distal level of the descending aorta, followed by reinsertion of the supra-aortic vessels, and ends with completion of the proximal anastomosis or by any kind of root repair as needed. RESULTS: Seven of 10 patients had prior surgery of the thoracic aorta. Indications for surgery were post-dissection aneurysm in 4 patients, true aneurysm in 3, anastomotic aneurysms in 2 and Type B aortic dissection with pseudo-coarctation in 1. Surgical access was performed through median sternotomy with left hemi-clamshell extension in all cases. There was no in-hospital mortality, but perioperative neurological symptoms occurred in 2 patients. These 2 patients developed delayed stroke (after awaking) after an initial uneventful clinical course, and in 1 of them, neurological symptoms resolved completely during follow-up. The median follow-up was 7 (± 13) months. There was no death and no need for additional redo surgery during this observational period. CONCLUSIONS: Extensive surgery of the thoracic aorta using a double arterial perfusion technique in order to avoid lower body hypothermic circulatory arrest is an attractive option. Further refinements of this technique may enable the safe and effective simultaneous multisegmental treatment of thoracic aortic pathology in patients who would otherwise have to undergo a two-step surgical approach.

Long-term results after proximal thoracic aortic redo surgery.

OBJECTIVE: To evaluate early and mid-term results in patients undergoing proximal thoracic aortic redo surgery. METHODS: We analyzed 60 patients (median age 60 years, median logistic EuroSCORE 40) who underwent proximal thoracic aortic redo surgery between January 2005 and April 2012. Outcome and risk factors were analyzed. RESULTS: In hospital mortality was 13%, perioperative neurologic injury was 7%. Fifty percent of patients underwent redo surgery in an urgent or emergency setting. In 65%, partial or total arch replacement with or without conventional or frozen elephant trunk extension was performed. The preoperative logistic EuroSCORE I confirmed to be a reliable predictor of adverse outcome- (ROC 0.786, 95%CI 0.64-0.93) as did the new EuroSCORE II model: ROC 0.882 95%CI 0.78-0.98. Extensive individual logistic EuroSCORE I levels more than 67 showed an OR of 7.01, 95%CI 1.43-34.27. A EuroSCORE II larger than 28 showed an OR of 4.44 (95%CI 1.4-14.06). Multivariate logistic regression analysis identified a critical preoperative state (OR 7.96, 95%CI 1.51-38.79) but not advanced age (OR 2.46, 95%CI 0.48-12.66) as the strongest independent predictor of in-hospital mortality. Median follow-up was 23 months (1-52 months). One year and five year actuarial survival rates were 83% and 69% respectively. Freedom from reoperation during follow-up was 100%. CONCLUSIONS: Despite a substantial early attrition rate in patients presenting with a critical preoperative state, proximal thoracic aortic redo surgery provides excellent early and mid-term results. Higher EuroSCORE I and II levels and a critical preoperative state but not advanced age are independent predictors of in-hospital mortality. As a consequence, age alone should no longer be regarded as a contraindication for surgical treatment in this particular group of patients.

Long-term results after operations for active infective endocarditis in native and prosthetic valves.

BACKGROUND: The objective of this study was to evaluate the midterm results of patients who underwent operations for active infective endocarditis. METHODS: Within a 10-year period, 141 patients with active infective endocarditis received surgical therapy. We assessed outcome, freedom from reinfection, and freedom from reintervention. Prosthetic valve endocarditis was included in this series. RESULTS: Surgical strategies included valve replacement with a tissue valve in 62% of patients and valve repair in 29% of patients. In 29% of patients, reconstruction of the aortomitral continuity, left ventricular outflow tract, or sinus of Valsalva was preferably performed with 1 or more bovine pericardial patches. In-hospital mortality was 11% and postoperative stroke rate was 7%. Multivariate logistic regression revealed multivalve involvement (p=0.052; odds ratio [OR], 5.84; 95% confidence interval [CI], 0.98-34.57), preoperative neurologic impairment (p=0.006; OR, 9.71; 95% CI, 1.92-49.09), and European system for cardiac operative risk evaluation (EuroSCORE) in quartiles (p=0.023; OR, 2.88; 95% CI, 1.15-7.17) to be independent predictors for in-hospital death. One-year and 5-year actuarial survival was 77% and 69%, respectively. One-year and 5-year actuarial freedom from reinfection was 100% and 90%, respectively. Freedom from reoperation at 5 years was 100%. Five-year survival was 74% for single-valve endocarditis and 46% for multivalve endocarditis (p<0.001). One-year freedom from reinfection was 100% for both single-valve and multivalve endocarditis; 5-year freedom from reinfection was 95% for single-valve endocarditis versus 67% for multivalve endocarditis (p=0.049). CONCLUSIONS: Despite a high early mortality during the first year, surgical intervention for active infective endocarditis provided excellent results with regard to freedom from reinfection and reoperation. A strategy of extensive debridement, reconstruction of destroyed cardiac structures using xenopericardium, followed by valve replacement or repair is highly effective and shows favorable long-term outcomes.

Growth potential of U-clip interrupted versus polypropylene running suture anastomosis in congenital cardiac surgery: intermediate term results.

Although U-clip anastomoses were studied for hemodynamics and patency, their potential for unimpeded growth after congenital cardiovascular surgery has not been investigated yet. In 53 children aged 2.1+/-3.3 years operated on between March 1998 and August 2005 growth of U-clip (U) vs. polypropylene running sutured (P) anastomoses in coarctation repair (Coarc; n=26), bi-directional Glenn (BDG; n=13) and arterial switch operation (ASO; n=14) was retrospectively analysed. Coarc showed 2.39+/-4.33 vs. 3.09+/-2.24 mm of growth during the observation period (21+/-16 vs. 30+/-27 months); no growth (0 vs.16%), restenosis (14 vs. 37%) and reinterventions (14 vs. 11%) were similar (all in U vs. P, P=ns). BDG showed 3.68+/-3.43 vs. 2.50+/-2.55 mm (P=ns) of growth during 15+/-5 vs. 29+/-18 months (P=0.046); no growth (17 vs. 0%), stenosis (0 vs. 14%) and reinterventions (0%) were similar in U vs. P, respectively (P=ns). Main pulmonary artery (MPA) anastomosis in ASO showed 0.28+/-1.73 vs. 1.30+/-3.16 mm of growth during 8+/-14 vs. 28+/-28 months; no growth (60 vs. 14%), stenosis (50 vs. 63%) and reinterventions (0%) were similar (all in U vs. P, P=ns). Anastomotic growth, stenosis and reintervention rates show no difference between interrupted U-clip and polypropylene running sutured technique in Coarc repair, BDG and MPA anastomosis in ASO.

Excellent outcome after surgical treatment of massive pulmonary embolism in critically ill patients.

OBJECTIVE: Treatment of central and paracentral pulmonary embolism in patients with hemodynamic compromise remains a subject of debate, and no consensus exists regarding the best method: thrombolytic agents, catheter-based thrombus aspiration or fragmentation, or surgical embolectomy. We reviewed our experience with emergency surgical pulmonary embolectomy. METHODS: Between January of 2000 and March of 2007, 25 patients (17 male, mean age 60 years) underwent emergency open embolectomy for central and paracentral pulmonary embolism. Eighteen patients presented in cardiogenic shock, 8 of whom had cardiac arrest and required cardiopulmonary resuscitation. All patients underwent operation with mild hypothermic cardiopulmonary bypass. Concomitant procedures were performed in 8 patients (3 coronary artery bypass grafts, 2 patent foramen ovale closures, 4 ligations of the left atrial appendage, 3 removals of a right atrial thrombus). Follow-up is 96% complete with a median of 2 years (range, 2 months to 6 years). RESULTS: All patients survived the procedure, but 2 patients died in the hospital on postoperative days 1 (intracerebral bleeding) and 11 (multiorgan failure), accounting for a 30-day mortality of 8% (95% confidence interval: 0.98-0.26). Four patients died later because of their underlying disease. Pre- and postoperative echocardiographic pressure measurements demonstrated the reduction of the pulmonary hypertension to half of the systemic pressure values or less. CONCLUSION: Surgical pulmonary embolectomy is an excellent option for patients with major pulmonary embolism and can be performed with minimal mortality and morbidity. Even patients who present with cardiac arrest and require preoperative cardiopulmonary resuscitation show satisfying results. Immediate surgical desobstruction favorably influences the pulmonary pressure and the recovery of right ventricular function, and remains the treatment of choice for patients with massive central and paracentral embolism with hemodynamic and respiratory compromise.

Complications associated with the arterial puncture closure device--Angio-Seal.

BACKGROUND: Arterial puncture closure devices (APCD) are frequently used after cardiac catheterization. Here, the diagnosis and therapy of femoral artery complications after the use of the Angio-Seal APCD is reported. PATIENTS AND METHODS: The Angio-Seal APCD was deployed in 1600 patients undergoing transfemoral catheterization. RESULTS: In 7 of 1600 cases (0.4%) vascular complications occurred following Angio-Seal deployment. Diagnosis was made by duplex sonography. Intraoperative findings consisted of a complete occlusion with dissection of the femoral artery in all patients. In 6 cases, the femoral bifurcation had to be reconstructed after endarterectomy. Follow-up is complete with a mean of 6 months. CONCLUSION: The Angio-Seal device should not be used for closure of the superficial femoral artery and in patients with severe arteriosclerosis. The application of arteriography as well as the use of ultrasound-guided puncture is advisable. In all cases, surgical intervention was successful and an adequate therapy for management of complications.