No-touch saphenous vein grafts in coronary artery surgery (SWEDEGRAFT): Rationale and design of a multicenter, prospective, registry-based randomized clinical trial.

The SWEDEGRAFT study (ClinicalTrials.gov Identifier: NCT03501303) tests the hypothesis that saphenous vein grafts (SVGs) harvested with the "no-touch" technique improves patency of coronary artery bypass grafts compared with the conventional open skeletonized technique. This article describes the rationale and design of the randomized trial and baseline characteristics of the population enrolled during the first 9 months of enrollment. The SWEDEGRAFT study is a prospective, binational multicenter, open-label, registry-based trial in patients undergoing first isolated nonemergent coronary artery bypass grafting (CABG), randomized 1:1 to no-touch or conventional open skeletonized vein harvesting technique, with a planned enrollment of 900 patients. The primary end point is the proportion of patients with graft failure defined as SVGs occluded or stenosed >50% on coronary computed tomography angiography at 2 years after CABG, earlier clinically driven coronary angiography demonstrating an occluded or stenosed >50% vein graft, or death within 2 years. High-quality health registries and coronary computed tomography angiography are used to assess the primary end point. The secondary end points include wound healing in the vein graft sites and the composite outcome of major adverse cardiac events during the first 2 years based on registry data. Demographics of the first 200 patients enrolled in the trial and other CABG patients operated in Sweden during the same time period are comparable when the exclusion criteria are taken into consideration. RCT# NCT03501303.

Quality of life is not improved after mitral valve surgery combined with epicardial left atrial cryoablation as compared with mitral valve surgery alone: a substudy of the double blind randomized SWEDish Multicentre Atrial Fibrillation study (SWEDMAF).

Aims: Concomitant surgical ablation of atrial fibrillation (AF) in patients undergoing mitral valve surgery (MVS) has almost become routine despite lack of convincing information about improved quality-of-life (QOL) and clinical benefit. Quality-of-life was therefore assessed after MVS with or without epicardial left atrial cryoablation. Methods and results: Sixty-five patients with permanent AF randomized to MVS with or without left atrial cryoablation, in the double-blinded multicentre SWEDMAF trial, replied to the Short Form 36 QOL survey at 6 and 12 months follow-up. The QOL scores at 12 month follow-up did not differ significantly between patients undergoing MVS combined with cryoablation vs. those undergoing MVS alone regarding Physical Component Summary mean 42.8 (95% confidence interval 38.3-47.3) vs. mean 44.0 (40.1-47.7), P = 0.700 or Mental Component Summary mean 53.1 (49.7-56.4) vs. mean 48.4 (44.6-52.2), P = 0.075. All patients, irrespective of allocated procedure, reached the same QOL after surgery as an age-matched Swedish general population. The Physical Component Summary in patients with sinus rhythm did also not differ from those in AF at 12 months; mean 45.4 (42.0-48.7) vs. mean 40.5 (35.5-45.6), P = 0.096) nor was there a difference in Mental Component Summary; mean 51.0 (48.0-54.1) vs. mean 49.6 (44.6-54.5), P = 0.581). Conclusion: Left atrial cryoablation added to MVS does not improve health-related QOL in patients with permanent AF, a finding that raises concerns regarding recommendations made for this combined procedure.

Influence of blood/tissue differences in contrast agent relaxivity on tracer-based MR perfusion measurements.

PURPOSE: Perfusion assessment by monitoring the transport of a tracer bolus depends critically on conversion of signal intensity into tracer concentration. Two main assumptions are generally applied for this conversion; (1) contrast agent relaxivity is identical in blood and tissue, (2) change in signal intensity depends only on the primary relaxation effect. The purpose of the study was to assess the validity and influence of these assumptions. MATERIALS AND METHODS: Blood and cerebral tissue relaxivities r1, r2, and r2* for gadodiamide were measured in four pigs at 1.5 T. Gadolinium concentration was determined by inductively coupled plasma atomic emission spectroscopy. Influence of the relaxivities, secondary relaxation effects and choice of singular value decomposition (SVD) regularization threshold was studied by simulations. RESULTS: In vivo relaxivities relative to blood concentration [in s(-1) mM(-1) for blood, gray matter (GM), white matter (WM)] were for r1 (2.614 ± 1.061, 0.010 ± 0.001, 0.004 ± 0.002), r2 (5.088 ± 0.952, 0.091 ± 0.008, 0.059 ± 0.014), and r2* (13.292 ± 3.928, 1.696 ± 0.157, 0.910 ± 0.139). Although substantial, by a nonparametric test for paired samples, the differences were not statistically significant. The GM to WM blood volume ratio was estimated to 2.6 ± 0.9 by r1, 1.6 ± 0.3 by r2, and 1.9 ± 0.2 by r2*. Secondary relaxation was found to reduce the tissue blood flow, as did the SVD regularization threshold. CONCLUSION: Contrast agent relaxivity is not identical in blood and tissue leading to substantial errors. Further errors are introduced by secondary relaxation effects and the SVD regularization.

Morphologic outcome after endovascular treatment of complicated type B aortic dissection.

PURPOSE: To investigate the long-term morphologic changes of the aorta after thoracic endovascular aortic repair (TEVAR) for acute complicated type B aortic dissection and to analyze whether these changes differed between DeBakey class IIIa and IIIb dissections. MATERIALS AND METHODS: During the period 1999-2009, 58 patients with acute complicated type B aortic dissection were treated with TEVAR. Seven patients lacked follow-up data, leaving 51 patients-17 patients with DeBakey IIIa aortic dissection and 34 patients with DeBakey IIIa aortic dissection IIIb-for inclusion in the study. Computed tomography scans performed before and after TEVAR were evaluated. Maximum thoracic and abdominal aortic diameters and diameters of the true lumen and false lumen at the level of the maximum aortic diameter in the thorax and abdomen were analyzed as well as degree of thrombosis of the false lumen. RESULTS: There was an overall significant reduction of the thoracic aortic diameter, increased true lumen diameter, and reduced false lumen diameter (P < .05). Total thrombosis of the false lumen, with or without reintervention, was seen in 53% of all patients, in 41% primarily and in 12% after reintervention. The IIIa group had a higher degree of total false lumen thrombosis. All patients in the IIIb group had total thrombosis of the false lumen along the stent graft. CONCLUSIONS: Long-term follow-up showed favorable aortic remodeling after TEVAR for acute complicated type B aortic dissection. Total thrombosis of the false lumen occurred more often in patients with DeBakey IIIa aortic dissection compared with patients with DeBakey IIIb aortic dissection.

Clinical Outcomes After Surgical Revascularization Using No-Touch Versus Conventional Saphenous Vein Grafts: Mid-Term Follow-Up of Propensity Score Matched Cohorts.

Previous studies have demonstrated superior patency of no-touch as compared to conventional saphenous vein grafts in coronary artery bypass grafting. We aimed to compare mid-term clinical outcomes of both techniques in a large cohort of routine patients. We identified all patients undergoing nonemergent primary coronary artery bypass grafting with either no-touch or conventional saphenous vein grafts at our institution between 2000 and 2020. Propensity score matching was used to create adjusted cohorts based on 5288 eligible patients. The primary outcome was the combined endpoint of all-cause mortality and repeat revascularization. Secondary outcomes were individual rates of all-cause mortality and repeat revascularization, surgical complications, and short-term mortality. Propensity score matching resulted in cohorts of no-touch (n = 923) and conventional (n = 923) saphenous vein grafted patients with comparable baseline characteristics. Mean follow-up time was significantly shorter for the no-touch compared to the conventional cohort (4.9 ± 2.3 vs 8.3 ± 2.6 years, P < 0.001). Up to 7-year follow-up, neither the rate of the primary composite endpoint nor death differed significantly between the cohorts. The rate of repeat revascularization was significantly higher in patients in the no-touch cohort (12.9% vs 9.3% at 7-year follow-up, P = 0.022. Post-hoc analysis of percutaneous coronary intervention during follow-up revealed comparable rates of saphenous vein graft failure (no-touch 42/923 (4.6%) vs conventional 32/923 (3.5%), P = 0.286). In this large propensity score matched registry study, coronary artery bypass with no-touch compared to conventional saphenous vein grafting did neither enhance mid-term survival nor reduce the rate of repeat revascularization.

Outcome of endovascular treatment of traumatic aortic transection.

OBJECTIVE: The purpose of this study was to analyze our experience of thoracic endovascular aortic repair (TEVAR) in patients with traumatic aortic transection. METHODS: This was a single-center consecutive case series that was conducted at the Uppsala University Hospital, Tertiary Referral Center. There were a total of 17 consecutive patients undergoing TEVAR for traumatic thoracic aortic transection. All patients undergoing TEVAR for aortic transection were registered prospectively and their medical records were reviewed regarding technical details, mechanism of injury, and concomitant injuries. Long-term outcome was analyzed with respect to need for reintervention and survival. RESULTS: Between 2001 and 2010, 17 patients underwent TEVAR for traumatic aortic injury. Median age was 42 years (range, 18-77 years), and 15 of 17 patients (88%) were men. Fourteen patients had been involved in motor vehicle accidents, two had fallen from heights, and one fell off a bicycle on a slope. In all cases, the aortic injury was located in the proximity of the origin of the left subclavian artery. All patients had concomitant injuries. In all patients, a single stent graft was sufficient to exclude the injured part of the aorta. The median cover length was 120 mm (range, 100-200 mm). In-hospital mortality was 24% (4 of 17 patients). One patient died perioperatively and three postoperatively, two from brain injuries and one from multiorgan failure. After a median follow-up of 36 months (range, 10-98 months), three patients underwent reintervention (18%), each patient only once; one for a type I endoleak, and two for pseudocoarctation secondary to stent graft infolding. Two were treated endovascularly, and one had a stent graft explantation. CONCLUSIONS: Endovascular repair allows rapid and minimally invasive therapy in patients with traumatic aortic injury with good technical results. The outcome is highly dependent on the severity of other concurrent injuries.

Mechanical Reperfusion Following Prolonged Global Cerebral Ischemia Attenuates Brain Injury.

Previous experiments demonstrated improved outcome following prolonged cerebral ischemia given controlled brain reperfusion using extracorporeal circulation. The current study further investigates this. Young adult pigs were exposed to 30 min of global normothermic cerebral ischemia, achieved through intrathoracic clamping of cerebral arteries, followed by 20 min of isolated mechanical brain reperfusion. Leukocyte-filtered blood was delivered by a roller-pump at fixed pressure and flow. One experimental group additionally had a custom-made buffer solution delivered at 1:8 ratio with the blood. Hemodynamics including intracranial pressure were monitored. Blood gases were from peripheral arteries and the sagittal sinus, and intraparenchymal brain microdialysis was performed. The brains were examined by a neuropathologist. The group with the added buffer showed lower intracranial pressure as well as decreased intraparenchymal glycerol and less signs of excitotoxicity and ischemia, although histology revealed similar degrees of injury. A customized mechanical reperfusion improves multiple parameters after prolonged normothermic global cerebral ischemia. Graphical Abstract The current study investigates if it possible to improve neurological outcomes following prolonged global brain ischemia. The results indicate that a customized mechanical reperfusion protocol can attenuate neurological injury.

Technical eligibility for endovascular treatment of the aortic arch after open type A aortic dissection repair.

OBJECTIVE: The objective was to report on the technical eligibility of patients previously treated for Stanford type A aorta dissection for endovascular aortic arch repair based on contemporary anatomic criteria for an arch inner-branched stent graft. METHODS: All patients treated for type A aorta dissection from 2004 to 2015 at a single aortic center were identified. Extent of repair and use of circulatory arrest were reported. Survival and reoperation were assessed using Kaplan-Meier and competing risk models. Anatomic assessment was performed using 3-dimensional computed tomography imaging software. Primary outcome was survival of 1 year or more and fulfillment of the arch inner-branched stent graft anatomic criteria. RESULTS: A total of 198 patients were included (158 DeBakey I, 32 DeBakey II, and 8 intramural hematoma). Mortality was 30 days (16.2%), 1 year (16.3%), and 10 years (45.0%). A total of 129 patients had imaging beyond 1 year (mean, 47.8 months), and 89 patients (69.0%) were eligible for arch inner-branched stent grafting. During follow-up, 19 patients (14.7%) met the threshold criteria for aortic arch treatment, of whom 14 (73.7%) would be considered eligible for arch inner-branched stent graft. Patients who underwent type A aorta dissection repair with circulatory arrest and no distal clamp were more often eligible for endovascular repair (88.8%) than those operated with a distal clamp (72.5%; P = .021). Among patients who did not meet the arch inner-branched stent graft anatomic criteria, the primary reasons were mechanical valve (40%) and insufficient proximal seal (30%). CONCLUSIONS: More than two-thirds of patients post-type A aorta dissection repair are technically eligible for endovascular arch inner-branched stent graft repair. The development of devices that can accommodate a mechanical aortic valve and a greater awareness of sufficient graft length would significantly increase availability.

Aortic rupture after spinal correction for scoliosis in the presence of a thoracic stent graft.

Corrective surgery for scoliosis often results in a lengthening of the spinal column and relative change of the position of the adjacent anatomical structures such as the aorta. The extent of these anatomical changes could be affected by the presence of a rigid aortic stent graft in the descending thoracic aorta. We present a case of aortic rupture after spinal correction for scoliosis in a 56-year-old female with a thoracic aortic stent graft. Extensive elongation of the aorta with concentration of the stress forces at the lower margin of the stent graft resulted in a weakening of the aortic wall and subsequent rupture.

Long-term survival and frequency of reinterventions after proximal aortic surgery: a retrospective study†.

OBJECTIVES: We sought to analyse perioperative outcome, long-term mortality, frequency and causes of reintervention, and survival benefit in a contemporary cohort of patients undergoing proximal thoracic aortic surgery. METHODS: Participants comprised all patients undergoing open surgery for proximal thoracic aortic aneurysm (TAA) (n = 319) and thoracic aortic dissection type A (TAD) (n = 229) during 2005-2014 at the Department of Thoracic Surgery, Uppsala University Hospital. Long-term survival was compared to age- and sex-matched controls. Perioperative mortality and morbidity, event-free survival and causes of reoperation were also analysed. RESULTS: Long-term mortality was normalized in patients with TAA, and a survival benefit was seen as early as 20 months when corrected for time lost due to perioperative mortality. Long-term survivors undergoing surgery for TAD, on the other hand, had a 10-year mortality of 130% [95% confidence interval (95% CI) 120-140%] compared to age- and sex-matched controls. Moreover, their event-free survival was half that of patients with TAA (hazard ratio 2.3; 95% CI 1.7-3.2). Reintervention (i.e. reoperation or thoracic endovascular aortic repair) was also twice as common in the TAD patients (odds ratio 2.0; 95% CI 1.1-3.5). The dominant causes for reoperation among TAD patients were aortic insufficiency, aortic arch aneurysm and infection. CONCLUSIONS: Surgery for TAA is relatively safe, normalizes long-term mortality and confers an early survival benefit. However, TAD surgery carries a high risk of perioperative mortality and morbidity, as well as increased long-term mortality and risk of reintervention.

Long-term clinical outcomes after coronary artery bypass grafting with pedicled saphenous vein grafts.

BACKGROUND: Coronary artery bypass grafting (CABG) using saphenous vein grafts (SVG) is vitiated by poor long-term patency of the vein grafts. Pedicled SVG harvested with the "no-touch" (NT) technique have demonstrated improved patency and could confer better outcomes. We aim to compare long-term results after CABG where NT or conventional technique was used for vein graft harvesting in a hypothesis-generating registry-based study. METHODS: Two propensity score matched cohorts (1349 patients) undergoing CABG with veins harvested with NT (NTT) or conventional (CT) technique in Sweden over the period 2005-2015 were used to compare long-term outcomes. Mortality, postoperative incidence of coronary angiography and need for reintervention was recorded and multivariable hazard ratios adjusted for risk factors were calculated. RESULTS: The mean follow-up time (SD) was 6.8 (3.3) years for NTT and 6.6 (3.2) years for CT. The adjusted hazard ratios for death, first angiography and need for reintervention for NTT patients were (95% CI) 0.97 (0.80-1.19), 0.76 (0.63-0.93), 0.91 (0.78-1.05), and 0.91 (0.71-1.17), respectively. Failed grafts were found in 43.2% of NTT patients and 53.6% of CT patients at angiography. CONCLUSIONS: In this study NT grafting was associated with a lower risk for repeat angiography, however no difference could be observed for mortality and need for reintervention. The earlier reported improvements in patency of NT veins could possibly be reflected in an improved clinical outcome during the first 10 years after surgery.

Application of cryoenergy to improve septal exposure during transaortic septal myectomy in hypertrophic obstructive cardiomyopathy.

For the past few decades, the transaortic septal myectomy (Morrow's procedure) has been the gold standard for treating severe left ventricular outflow tract obstruction in hypertrophic obstructive cardiomyopathy (HOCM) patients. 30-day mortality has been reported at less than 1% in dedicated centers. However, in a subgroup of patients, the interventricular septal obstruction is localized very distally, below the aortic valve plane, and the transaortic approach can be very challenging. A subset of these patients can present with residual obstruction after surgery, due to inadequate length of septal excision, leading to reoperation. The aim of this work is to illustrate an original application of cryoenergy to improve the transaortic exposure of the interventricular septum and thus enable surgeons to perform very distal myectomies in HOCM patients.

Protein Profiling in Serum and Cerebrospinal Fluid Following Complex Surgery on the Thoracic Aorta Identifies Biological Markers of Neurologic Injury.

Surgery on the arch or descending aorta is associated with significant risk of neurological complications. As a consequence of intubation and sedation, early neurologic injury may remain unnoticed. Biomarkers to aid in the initial diagnostics could prove of great value as immediate intervention is critical. Twenty-three patients operated in the thoracic aorta with significant risk of perioperative neurological injury were included. Cerebrospinal fluid (CSF) and serum were obtained preoperatively and in the first and second postoperative days and assessed with a panel of 92 neurological-related proteins. Three patients suffered spinal cord injury (SCI), eight delirium, and nine hallucinations. There were markers in both serum and CSF that differed between the affected and non-affected patients (SCI; IL6, GFAP, CSPG4, delirium; TR4, EZH2, hallucinations; NF1). The study identifies markers in serum and CSF that reflect the occurrence of neurologic insults following aortic surgery, which may aid in the care of these patients.

Thoracic aortic aneurysm and dissection: increasing prevalence and improved outcomes reported in a nationwide population-based study of more than 14,000 cases from 1987 to 2002.

BACKGROUND: Current knowledge of prevalence, incidence, and survival in thoracic aortic diseases (aneurysm and dissection) is based on small studies from a dated era of treatment and diagnostic procedures. The objective of the present study was to reappraise epidemiology and long-term outcomes in subjects with thoracic aortic disease in a large contemporary population. METHODS AND RESULTS: All subjects with thoracic aortic aneurysm or dissection identified in Swedish national healthcare registers from 1987 to 2002 were included in the present study. Of 14,229 individuals with thoracic aortic disease, 11,039 (78%) were diagnosed before death. Incidence of thoracic aortic disease rose by 52% in men and by 28% in women to reach 16.3 per 100,000 per year and 9.1 per 100,000 per year, respectively. Operations increased 7-fold in men and 15-fold in women over time. Of the 2455 patients who underwent operation, 389 (16%) died within 30 days, with older age and thoracic aortic rupture as risk factors. In Cox analysis, increasing age was the only variable associated with long-term mortality. Both short- and long-term mortality improved over time. In patients who underwent operation, actuarial survival (95% CI) at 1, 5, and 10 years was 92% (91% to 93%), 77% (75% to 80%), and 57% (53% to 61%), respectively. The cumulative incidence of thoracic aortic reoperations was 7.8% at 10 years. CONCLUSIONS: The prevalence and incidence of thoracic aortic disease was higher than previously reported and increasing. The annual number of operations increased substantially. Surgical (30-day) and long-term survival improved significantly over time to form a growing cohort of patients needing counseling, management decisions, operations, and extended postoperative surveillance.

Role of aggregated medin in the pathogenesis of thoracic aortic aneurysm and dissection.

The pathogenesis of sporadic thoracic aortic aneurysm and dissection, which may lead to rupture of the aorta, remains largely unknown. Amyloid deposits, formed from the medin peptide, are very prevalent in the media of the thoracic aorta. We have studied the occurrence of medin-derived amyloid in specimens from patients with thoracic aortic aneurysm, aortic dissection type A and normal dimensioned aorta. Surprisingly, the amount of amyloid was significantly lower in the aneurysm and dissection groups (0.63+/-0.13 and 0.36+/-0.24 amyloid particles per mm2, respectively) compared to the control material (2.37+/-0.58). However, focal medin immunoreactivity not associated with amyloid was found more conspicuously in the media of the two diseased groups. Recent amyloid research indicates that prefibrillar oligomeric aggregates, rather than mature amyloid fibrils, are toxic to the surrounding cells. The non-amyloid medin immunoreactivity observed may represent such toxic oligomers. This is supported by the fact that aggregated medin induced death of aortic smooth muscle cells in vitro. In addition, cells incubated together with medin increased the production of matrix metalloproteinase-2, a protease that degrades elastin and collagen and subsequently weakens the vessel wall. We therefore propose that medin oligomers are involved in the degeneration process of sporadic thoracic aortic aneurysm and dissection.

Surgical and long-term mortality in 2634 consecutive patients operated on the proximal thoracic aorta.

OBJECTIVE: To assess surgical and long-term mortality in a large, contemporary, unselected cohort of patients undergoing operations on the proximal thoracic aorta. METHODS: Patients in the Swedish Heart Surgery register operated 1992-2004 were identified and data cross-linked with the in-hospital and cause-of-death registers. Factors associated with surgical, intermediate, and long-term mortality were studied with separate Cox analyses. Long-term survival was estimated by Kaplan-Meier analysis. RESULTS: 2634 patients (68% men, mean age 60 years) were operated for aortic aneurysm (n=1821, 69%) or aortic dissection (n=813, 31%). Overall, increased age, aortic dissection, emergency operation, coronary artery bypass grafting, postoperative stroke, and postoperative renal failure were independently associated with surgical mortality. Only age was independently associated with long-term mortality. Later era of treatment (1998-2004 vs 1992-1997) was associated with lower risk only for aneurysm patients, despite similar changes in surgical approach. Long-term survival for all patients was 83% at 1 year, 77% at 5 years, and 73% at 10 years and identical for aneurysm and dissection when adjusted for surgical mortality. CONCLUSIONS: Increased age was associated with increased mortality across follow-up, implicating early surgery when possible. Results improved over time for aneurysms but not dissections; however, long-term survival was equal.

Mechanical reperfusion with leucocyte-filtered blood does not prevent injury following global cerebral ischaemia.

Objectives: Prolonged global cerebral ischaemia leads to irreversible injury, often with lethal outcome. Brain injuries are partly caused by the uncontrolled reperfusion that occurs once the circulation is re-established. Recent animal experiments suggest that controlled reperfusion following lengthy ischaemia might prevent severe brain injury. This study aimed at further exploring cerebral alterations and outcome following prolonged global cerebral ischaemia and mechanically manipulated reperfusion. Methods: Three groups of pigs were included; one sham operated ( n = 3) and two that underwent 30-min global cerebral ischaemia. All vessels that supply the brain were isolated intrathoracically, after which they were occluded for 30 min in the ischaemic groups. In one of the ischaemic groups uncontrolled reperfusion was applied (URep, n = 6), i.e. normal circulation was restored 30 min after arrested cerebral circulation. The second ischaemic group received mechanical reperfusion (MRep, n = 6) with leucocyte-filtered blood at constant flow and pressure for 20 min using extracorporeal circulation following the 30-min ischaemia, after which normal blood flow resumed. All animals were monitored for 3 h after start of uncontrolled reperfusion. Haemodynamic parameters, arterial and sagittal sinus blood gases, cerebral oxygen extraction rates and intraparenchymal biomarkers using microdialysis were measured. Brain histology was performed post-mortem. Results: Global brain ischaemia led to the same extent of severe morphological changes at the level of light microscopy in the two ischaemic experimental groups, regardless of reperfusion protocol. Furthermore, no significant differences were found between the URep and MRep groups regarding cerebral blood gases or microdialysis biomarkers. Conclusions: Mechanical reperfusion following the current protocol does not modify brain alterations caused by 30 min of arrested cerebral circulation.

Blood Flow Quantitation by Positron Emission Tomography During Selective Antegrade Cerebral Perfusion.

BACKGROUND: Perfusion strategies during aortic surgery usually comprise hypothermic circulatory arrest (HCA), often combined with selective antegrade cerebral perfusion (SACP) or retrograde cerebral perfusion. Cerebral blood flow (CBF) is a fundamental parameter for which the optimal level has not been clearly defined. We sought to determine the CBF at a pump flow level of 6 mL/kg/min, previously shown likely to provide adequate SACP at 20°C in pigs. METHODS: Repeated positron emission tomography (PET) scans were used to quantify the CBF and glucose metabolism throughout HCA and SACP including cooling and rewarming. Eight pigs on cardiopulmonary bypass were assigned to either HCA alone (n = 4) or HCA+SACP (n = 4). The CBF was measured by repeated [15O]water PET scans from baseline to rewarming. The cerebral glucose metabolism was examined by [18F]fluorodeoxyglucose PET scans after rewarming to 37°C. RESULTS: Cooling to 20°C decreased the cortical CBF from 0.31 ± 0.06 at baseline to 0.10 ± 0.02 mL/cm3/min (p = 0.008). The CBF was maintained stable by SACP of 6 mL/kg/min during 45 minutes. After rewarming to 37°C, the mean CBF increased to 0.24 ± 0.07 mL/cm3/min, without significant differences between the groups at any time-point exclusive of the HCA period. The net cortical uptake (Ki) of [18F]fluorodeoxyglucose after rewarming showed no significant difference between the groups. CONCLUSIONS: Cooling autoregulated the CBF to 0.10 mL/cm3/min, and 45 minutes of SACP at 6 mL/kg/min maintained the CBF in the present model. Cerebral glucose metabolism after rewarming was similar in the study groups.

Staphylococcus aureus bloodstream infection after cardiac surgery: risk factors and outcome.

Thirty-eight patients (10 cases and 28 controls) were included in a case-control study of Staphylococcus aureus bloodstream infection after cardiac surgery in 833 patients. All bacterial strains were found to be unique by pulsed-field gel electrophoresis. In multivariable risk-factor analysis, only valve prosthesis implantation was associated with bloodstream infection. The early and late case mortality rate was 0%.

Lactadherin binds to elastin--a starting point for medin amyloid formation?

Medin amyloid is found in the medial layer of the aorta in almost 100% of the Caucasian population over 50 years of age. The medin fragment is 5.5 kDa and derives from the C2-like domain of the precursor protein lactadherin. We have previously reported immunohistochemical findings showing that medin amyloid co-localizes with elastic fibers of arteries and herein we show that lactadherin also is associated with elastic structures of human aortic material. In addition, results from in vitro binding assays demonstrate that both medin and lactadherin bind to tropoelastin in a concentration-dependent fashion, suggesting that the lactadherin-tropoelastin interaction is mediated via the medin domain. It is possible that lactadherin, which is a cell adhesion protein, in this way connects smooth muscle cells to the elastic fibers of arteries. Given that both medin and lactadherin interact with elastic fibers, elastin is probably an important component in the formation of medin amyloid.