Laser assisted pulmonary metastasectomy promises a low local recurrence rate.

Pulmonary metastasectomy (PM) is consensually performed in a parenchyma-sparing manner to preserve functionally healthy lung tissue. However, this may increase the risk of local recurrence at the surgical margin. Laser assisted pulmonary metastasectomy (LPM) is a relatively recent innovation that is especially useful to resect multiple metastatic pulmonary nodules. In this study we investigated the rate of local recurrence after LPM and evaluated the influence of various clinical and pathological factors on local recurrence. Retrospectively, a total of 280 metastatic nodules with different histopathological entities were studied LPM from 2010 till 2018. All nodules were resected via diode-pumped neodymium: yttrium-aluminum-garnet (Nd:YAG) 1,318 nm laser maintaining a safety margin of 5 mm. Patients included were observed on average for 44 ± 17 months postoperatively. Local recurrence at the surgical margin following LPM was found in 9 nodules out of 280 nodules (3.21%). Local recurrence at the surgical margin occurred after 20 ± 8.5 months post operation. Incomplete resection (p = < 0.01) and size of the nodule (p = < 0.01) were associated with significantly increased risk of local recurrence at the surgical margin. Histology of the primary disease showed no impact on local recurrence. Three and five-year survival rates were 84% and 49% respectively. Following LPM, the rate of local recurrence is low. This is influenced by the size of the metastatic nodules and completeness of the resection. Obtaining a safety margin of 5 mm seems to be sufficient, larger nodules require larger safety margins.

Bilateral papillary muscle repositioning: successful repair of functional mitral regurgitation in dilative cardiomyopathy.

OBJECTIVES: Functional mitral regurgitation (FMR) in patients with non-ischaemic dilative cardiomyopathy (DCM) is associated with heart failure and poor outcome. Aggressively undersized annuloplasty as an annular solution for a ventricular problem ameliorates heart failure but may be associated with recurrent FMR and does not improve survival. We sought to analyse if moderately undersized annuloplasty with repositioning of both papillary muscles can lead to improved valve stability and outcome in patients with DCM and FMR. METHODS: In 66 patients with DCM-associated FMR (age 66 ± 12 years, ejection fraction 29 ± 6% and mean pulmonary artery pressure 35 ± 11 mmHg) and severe leaflet tethering (tenting height ≥10 mm) bilateral papillary muscle repositioning was added to moderately undersized ring annuloplasty (median size 30 mm). Concomitant surgery included tricuspid valve repair in 86% of patients and atrial ablation in 44%. RESULTS: The early mortality rate was 9%. Overall 5-year freedom from all-cause death, left ventricular assist device implantation or heart transplant was 58% (95% confidence interval 45-71%). Six patients underwent reoperation (redo repair n = 4). Reverse remodelling was observed during follow-up in 66% of patients with decreasing left ventricular end-diastolic diameters (66 ± 5 to 61 ± 12 mm; P < 0.001) and left ventricular end-systolic diameters (56 ± 9 to 51 ± 14 mm; P = 0.001). Subgroup analyses (partial versus complete ring, preoperative left ventricular end-diastolic diameters <65 mm vs left ventricular end-diastolic diameter ≥65 mm) documented similar survival rates. A competing risks regression analysis identified cerebral vascular disease (P = 0.01), use of a partial ring (P = 0.03) and absence of tricuspid valve repair (P = 0.03) as independent predictors of death. CONCLUSIONS: The combination of bilateral papillary muscle repositioning and moderately undersized ring annuloplasty leads to stable mid-term repair results and reverse remodelling in patients with DCM and FMR and severe leaflet tethering.

[Epidemiology, Clinical Presentation, Diagnosis and Treatment of Infections Caused by Mycobacterium chimaera]. / Epidemiologie, Klinik, Diagnostik und Therapie von Infektionen durch Mycobacterium chimaera.

The recognition, correct diagnosis and adequate clinical management of infections caused by atypical mycobacteria are challenging tasks in clinical practice. Invasive infections caused by Mycobacterium chimaera, a member of the Mycobacterium avium-intracellulare complex, have been increasingly reported over the past few years. Most infections occurred in patients who had undergone open-chest cardiothoracic surgery. Epidemiological and molecular studies showed that transmission of M. chimaera occurred through intraoperative aerosols derived from contaminated heater-cooler units, i. e. devices that are used to enable the extracardiac circuit in cardiothoracic surgery. Thus far, approximately 120 patient cases have been reported worldwide. The latency between exposure and onset of clinical symptoms may comprise several years. Clinical manifestations of M. chimaera infections include not only endocarditis and implant-associated infections, but also non-cardiac entities such as sarcoidosis-like symptoms, vertebral osteomyelitis and chorioretinitis. The pathogen can be detected in blood culture vials and in surgically obtained specimens from affected tissues, if specific microbiological tests for detection of mycobacteria are employed. There are no simple-to-use screening tests and a high clinical index of suspicion is thus mandatory in patients with previous exposure and compatible signs and symptoms. The successful treatment of M. chimaera infections requires the removal of infected devices and prolonged combination therapy with antimycobacterial drugs. This review summarises the clinical relevance, epidemiology, symptomatology, diagnosis and treatment of infections caused by M. chimaera, with a specific focus on pneumological aspects.

[Chronic thromboembolic pulmonary hypertension: Recommendations of the Cologne Consensus Conference 2016]. / Chronisch thromboembolische pulmonale Hypertonie: Empfehlungen der Kölner Konsensus Konferenz 2016.

The 2015 European Guidelines on Pulmonary Hypertension did not cover only pulmonary arterial hypertension (PAH), but also other significant subgroups of pulmonary hypertension (PH). In June 2016, a Consensus Conference organized by the PH working groups of the German Society of Cardiology (DGK), the German Society of Respiratory Medicine (DGP) and the German Society of Pediatric Cardiology (DGPK) was held in Cologne, Germany to discuss open and controversial issues surrounding the practical implementation of the European Guidelines. Several working groups were initiated, one of which was dedicated to the diagnosis and treatment of chronic thromboembolic pulmonary hypertension (CTEPH). In every patient with PH of unknown cause CTEPH should be excluded. The primary treatment option is surgical pulmonary endarterectomy (PEA) in a specialized multidisciplinary CTEPH center. Inoperable patients or patients with persistent or recurrent CTEPH after PEA are candidates for targeted drug therapy. For balloon pulmonary angioplasty (BPA), there is currently only limited experience. This option - as PEA - is reserved to specialized centers with expertise for this treatment method. In addition, a brief overview is given on pulmonary artery sarcoma, since its surgical treatment is often analogous to PEA. The recommendations of this working group are summarized in the present paper.

[Chronic thromboembolic pulmonary hypertension--a position paper]. / Chronisch thromboembolische pulmonale Hypertonie (CTEPH) 2014. Ein Positionspapier.

This position paper summarises current developments in chronic thromboembolic pulmonary hypertension (CTEPH) including diagnostic approaches and treatment options. Based on the guidelines of the task force of CTEPH experts at the 5th World Symposium on Pulmonary Hypertension in Nice 2013. Open questions arising during the treatment of patients with CTEPH are addressed. Patients with suspected CTEPH should undergo echocardiography and cardiopulmonary exercise testing. A ventilation/perfusion scan is the recommended imaging test for screening in the diagnostic algorithm for the evaluation of CTEPH. CTEPH-patients should be discussed in an expert center with an interdisciplinary team and an experienced PEA surgeon to decide the further treatment. Pulmonary endarterectomy (PEA) is the treatment of choice for patients with CTEPH. Medical therapy with PH-targeted medications for inoperable CTEPH and residual disease after PEA should only be initiated if evaluation reveals that the patient is no candidate for a PEA. Current data suggest that CTEPH patients treated with PEA have a better long-term survival rate and quality of life than patients treated with medical therapy.

[Chronic thromboembolic pulmonary hypertension: Time delay from onset of symtoms to diagnosis and clinical condition at diagnosis]. / Chronisch thromboembolische pulmonale Hypertonie: Latenz bis zur Diagnosesicherung und klinischer Zustand bei Diagnosestellung.

BACKGROUND AND AIM: Chronic-thromboembolic pulmonary hypertension (CTEPH) is a serious complication of acute pulmonary embolism (PE). In untreated patients prognosis is poor. It depends on WHO-functional class. A delay from onset of symptoms and diagnosis can lead to a further worsening of prognosis. A pulmonary endarterectomy is the treatment of choice. We aimed to evaluate the time delay from onset of symptoms to diagnosis and the WHO-functional class at primary diagnosis in patients with CTEPH. PATIENTS AND METHODS: Retrospective analysis of data from 70 monocentrically registered patients (48 women, 22 men, mean age 66,2 years  ± â€Š13,8 years) with confirmed CTEPH from the pulmonary hypertension expert center Missionsärztliche Klinik. Diagnostic work-up was performed according to the current guidelines. RESULTS: Mean delay from onset of symptoms to diagnosis of CTEPH was 18 ±â€Š26 months. Time delay was only slightly shorter in patients with a history of PE (n = 56; 81 %) than in patients without a history of PE (n = 13; 19 %): 16,9  ± â€Š23,8 vs. 23,5 â€Š± â€Š36,9 months. Time delay was higher in patients who received vasoactive medication before the first contact with a PH expert center and in patients who were classified as technically not suitable for a thrombendarterectomy. 38 patients with a history of acute PE did not have a period without symptoms. In 18 patients symptoms had transiently gone after PE. More than 70 % presented in WHO functional class III or IV. CONCLUSION: Time delay between onset of symptoms and diagnosis of CTEPH and referral to a PH expert center is long and the majority of patients presented in WHO-functional class III or IV. Prognosis is poor in untreated patients and getting worse with a higher WHO-functional class. For this reason, and because CTEPH can be cured by a pulmonary endarterectomy, each patient with suspected PH should be referred to a PH expert center to exclude CTEPH.

Vasopressin induces rectosigmoidal mucosal ischemia during cardiopulmonary bypass.

BACKGROUND: Lower gastrointestinal complications are rare after cardiac surgery with cardiopulmonary bypass (CPB). However, if they occur, they are associated with a high mortality. Endothelin (ET) expression and microcirculatory dysfunction have been shown to be involved in a variety of diseases of the lower gastrointestinal tract. The aim of this study was to analyze whether CPB with or without additional vasopressin administration affects the rectosigmoidal mucosal microcirculation and whether this involves the ET system. METHODS: Pigs were randomized in three groups (n = 6 each): I Sham, II CPB: 1 hour CPB, III CPB + vasopressin: 1 hour CPB and vasopressin (0.006 U/min kg) administration maintaining baseline arterial pressure. All animals were reperfused for 90 minutes. During the experiment hemodynamics and rectosigmoidal mucosal microcirculation were measured continuously. The rectosigmoidal mucosal expression of endothelin-1 (ET-1) and its receptor subtypes A (ETA ) and B (ETB ) were determined using PCR and Western blot analysis. RESULTS: CPB did not change rectosigmoidal microvascular blood flow compared to baseline (68.1 ± 4.0 vs. 75.5 ± 6.6 AU; p = 0.4), but increased ET-1 (gene, 7.8 ± 1.5 vs. 2.3 ± 0.6 RQ; p = 0.002 and protein, 12.0 ± 0.5 vs. 6.9 ± 0.3 OD mm(2) ; p < 0.001), ETA (gene, 2.3 ± 0.6 vs. 0.6 ± 0.1 RQ; p < 0.001 and protein, 11.0 ± 0.3 vs. 6.2 ± 1.1 OD mm(2) ; p = 0.006) and ETB (gene, 6.7 ± 1.2 vs. 1.9 ± 0.3 RQ; p < 0.001 and protein, 25.6 ± 1.4 vs. 14.9 ± 1.5 OD mm(2) ; p = 0.002) expression compared to Sham. Vasopressin during CPB reduced the rectosigmoidal blood flow compared to baseline (26.5 ± 4.9 vs. 75.5 ± 6.6 AU, p < 0.001), and blunted the CPB-induced increase of ET-1 (gene, 1.2 ± 0.4 RQ, p = 0.1 and protein, 8.1 ± 1.6 OD mm(2) , p = 0.5 vs. Sham), ETA (gene, 0.6 ± 0.1 RQ, p = 1.0 and protein, 7.0 ± 0.6 OD mm(2) , p = 0.6 vs. Sham) and ETB (gene, 1.3 ± 0.3 RQ, p = 0.1 and protein, 19.4 ± 2.1 OD mm(2) , p = 0.1 vs. Sham). CONCLUSION: CPB does not significantly affect rectosigmoidal mucosal microcirculation; however, it upregulates ET-1, ETA , and ETB . Vasopressin blunts the CPB-induced elevation of ET-1, ETA , and ETB and induces rectosigmoidal mucosal ischemia during CPB.

Dynamic annuloplasty for mitral regurgitation.

OBJECTIVE: The MiCardia DYANA annuloplasty system (MiCardia Corp, Irvine, Calif) is a nitinol-based dynamic complete ring that allows modification of the septal-lateral diameter under transesophageal echocardiography guidance in the loaded beating heart after mitral valve repair. Shape alteration is induced by radiofrequency via detachable activation wires. This multicenter study reports the first human experience with this device. METHODS: Patients (n = 35, 67 ± 8 years) with degenerative (n = 29), functional/ischemic (n = 5), or rheumatic (n = 1) mitral regurgitation underwent mitral valve repair using the new device. We analyzed the occurrence of death, endocarditis, ring dehiscence, systolic anterior motion, thromboembolism, pulmonary edema, heart block, ventricular arrhythmia, hemolysis, or myocardial infarction at 30 days (primary end point) and 6 months (secondary end point) postprocedure. RESULTS: All patients exhibited mitral regurgitation of 2 or less early postoperatively and at 6 months follow-up. In 29 patients, the initial mitral valve repair result was satisfactory and no ring activation was required. In 6 patients, the nitinol-based ring was deformed intraoperatively postrepair with further improvement of mitral regurgitation in all cases (preactivation: 0.9 ± 0.2, postactivation: 0.2 ± 0.3; P = .001). One death (2.9%, multisystem organ failure, non-device related), 2 ventricular arrhythmias (5.7%), and 1 heart block (2.9%) occurred, all in the first 30 days after surgery. No additional major adverse clinical events occurred later than 1 month postprocedure (total observed major adverse clinical event rate 11.5%). CONCLUSIONS: The implantation of the new dynamic annuloplasty ring allows for safe mitral valve repair. The option of postrepair modification of the septal-lateral diameter by radiofrequency may further optimize repair results.

A scoring system for the assessment of angiographic findings in non-occlusive mesenteric ischemia (NOMI).

PURPOSE: To establish a standardized scoring system for angiographic findings in patients with non-occlusive mesenteric ischemia (NOMI). MATERIALS AND METHODS: In 36 patients (mean age: 72 years), 53 angiographies of the superior mesenteric artery (SMA) were performed for suspected NOMI after cardiac or major aortic surgery. All examinations were performed using a standardized DSA technique. Two experienced radiologists performed a consensus reading blinded to the clinical information, on two occasions with an interval of two weeks. In order to investigate the reproducibility of the criteria, the images were assessed once by an intensivist and a medical student. Image analysis was performed with respect to vessel morphology, reflux of contrast medium into the aorta, small bowel parenchymal contrast enhancement and distension and the delay between arterial injection and portal vein filling. RESULTS: Almost perfect intra-observer correlation was obtained for the assessment of the contrast medium reflux (κ = 0.82) and substantial correlation for the time of portal vein filling (κ = 0.66). Moderate correlations were obtained for the vessel morphology (κ = 0.51), small bowel enhancement (κ = 0.63) and distension (κ = 0.53). Contrast medium reflux into the aorta (κ = 0.77 and 0.63) and the time of portal vein filling (κ = 0.42 and 0.58) resulted in the highest inter-observer correlations between the radiologists and the intensivist as well as the radiologists and the student. CONCLUSION: In patients with suspected NOMI, using our scoring system yields high intra- and inter-observer correlations, allowing a standardized evaluation of angiographic findings.

A 13-year-old girl with arterial hypertension - mid-aortic syndrome.

Mid-aortic stenosis (MAS) is a rare clinical entity that is characterised by profound narrowing of the abdominal aorta. MAS usually presents with severe hypertension. Treatment modalities include antihypertensive medication, angioplasty, and surgery. If adequate treatment is initiated long-term prognosis is favourable. Here, we report on 13-year-old girl with MAS who presented to our hospital with arterial hypertension. Initial diagnostic work-up and treatment in patients with MAS are presented.

[Chronic thromboembolic pulmonary hypertension: recommendations of the Cologne Consensus Conference 2010]. / Chronisch thromboembolische pulmonale Hypertonie: Empfehlungen der Kölner Konsensus-Konferenz 2010.

In the 2009 European Guidelines on pulmonary hypertension one section covers aspects of pathophysiology, diagnosis and treatment of chronic thromboembolic pulmonary hypertension (CTEPH). The practical implementation of the guidelines for this disease is of crucial importance, because CTEPH is a form of pulmonary hypertension which can be surgically cured. It is, however, frequently diagnosed late in the course of disease and often treated not correctly. In the European Guidelines CTEPH is addressed relatively briefly, although it is a common form of PH which is often overlooked. Any patient with unexplained PH should be evaluated for the presence of CTEPH. A ventilation/perfusion lung scan is recommended as the first step to exclude CTEPH. If the ventilation/perfusion lung scan or multislice CT angiography reveals perfusions defects suggesting the diagnosis of CTEPH, the patient should be referred to a centre with expertise in the medical and surgical management of these patients. After diagnosis of CTEPH the case has to be reviewed by an experienced surgeon in a PEA centre for assessment of operability. The recommendations of the European guidelines are summarized in the current manuscript with additional comments regarding diagnosis and treatment according to most recent evidence.

[Carotid artery stenosis: current state of therapy]. / Karotisstenose: Aktueller Stand der Therapie.

Ipsilateral occlusive or embolizing carotid artery stenoses are found in 20-30% of all cases of ischemic stroke. Several randomized studies revealed endarterectomy to be the gold standard in the therapy of severe symptomatic (NASCET, ESCT) and to some extent of asymptomatic carotid stenoses (ACAS, ACST). Stent angioplasty has been established as an alternative therapeutic option although non-inferiority of this procedure has not yet been proven. We provide an overview of both procedures as well of the state of current trials.

[Quality in aortic valve replacement--how good have hybrid valves have to be?]. / Qualität der chirurgischen Behandlung von Aortenklappenvitien. Welche Verbesserungen sind von Hybridklappen zu erwarten?

The current enthusiasm with the development of catheter-based aortic valve replacement suggests a critical appraisal of the quality of conventional techniques. Currently surgical treatment of diseased aortic valves includes different methods that can be employed with a low risk. Risk prediction is difficult, the Euroscore largely overestimates mortality. By comparison, there is no evidence that the risk of implantation is reduced by catheter-based implantation. Specific complications (stroke, AV-block, perivalvular leak) are more frequent compared to conventional replacement. Despite the current enthusiasm over the feasibility of catheter-based implantation of hybrid aortic valves they should still be used cautiously.

The PPAR-gamma agonist rosiglitazone facilitates Akt rephosphorylation and inhibits apoptosis in cardiomyocytes during hypoxia/reoxygenation.

BACKGROUND AND AIM: Results on the cardiovascular effects of PPAR-gamma agonists are conflicting. On one hand, it was suggested that the PPAR-gamma agonist rosiglitazone may increase the risk of cardiovascular events. On the other hand, PPAR-gamma agonists reduce myocardial infarct size and improve myocardial function during ischemia/reperfusion in animal studies in vivo. However, the mechanism of this effect is unclear, and it is open if PPAR-gamma agonists have a direct effect on cardiac myocyte survival in ischemia/reperfusion. The aim of this study was to determine the effect of the PPAR-gamma agonist rosiglitazone on hypoxia/reoxygenation-induced apoptosis of isolated cardiomyocytes. METHODS: Isolated rat cardiac myocytes were pretreated with rosiglitazone or vehicle for 30 min before they were subjected to hypoxia for 4 h followed by different times of reoxygenation (5 min to 12 h). Apoptosis was determined by in situ hybridization for DNA fragmentation (TUNEL) as well as detection of cytoplasmic accumulation of histone-associated DNA fragments by enzyme-linked immunosorbent assay (ELISA). Activation of apoptosis regulating intracellular signalling pathways was studied by immunoblotting using phosphospecific antibodies. RESULTS: Rosiglitazone significantly reduced apoptosis of isolated cardiomyocytes subjected to hypoxia/reoxygenation, independently determined with two methods. After 4 h of hypoxia and 12 h of reoxygenation, 34 +/- 3.6% of the vehicle treated cardiac myocytes stained positive for DNA fragmentation in the TUNEL staining. Rosiglitazone treatment reduced this effect by 23% (p < 0.01). Even more pronounced, cytoplasmic accumulation of histone-associated DNA fragments detected by ELISA was reduced by 35% (p < 0.05) in the presence of rosiglitazone. This inhibition of hypoxia/reoxygenation-induced apoptosis was associated with an increased reoxygenation-induced rephosphorylation of the protein kinase Akt, a crucial mediator of cardiomyocyte survival in ischemia/reperfusion of the heart. This effect was reversed by GW-9662, an irreversible PPAR-gamma antagonist. However, rosiglitazone did not alter phosphorylation of the MAP kinases ERK1/2 and c-Jun N-terminal kinase (JNK). CONCLUSION: It can be concluded that cardiac myocytes are direct targets of PPAR-gamma agonists promoting its survival in ischemia/reperfusion, at least in part by facilitating Akt rephosphorylation. This effect may be of clinical relevance inhibiting the reperfusion-induced injury in patients suffering from myocardial infarction or undergoing cardiac surgery.

Impaired detection of Mycobacterium tuberculosis immunity in patients using high levels of immunosuppressive drugs.

We have previously shown, in renal transplant recipients on maintenance immunosuppression, that a whole-blood assay was superior in detecting immunity towards purified protein derivative (PPD) compared with skin testing. As blood tests may have limitations during high-dose immunosuppression therapy, the present study was aimed at characterising the effect of high immunosuppressive drug levels on PPD-specific T-cell immunity. PPD-reactive CD4 T-cells from 13 renal transplant recipients were longitudinally quantified by the induction of cytokines using flow cytometry. To further address the effect of high and low maintenance immunosuppression, drug effects were studied in vitro and in 49 age-matched lung transplant recipients and 49 renal transplant recipients. Maintenance immunosuppression after renal transplantation did not affect PPD-specific T-cell detection (median T-cell frequencies 0.55% before and 0.46% >12 months after transplantation), whereas specific T-cell frequencies were significantly lower 3 months after transplantation (0.15%; p = 0.0002). Likewise, high-level maintenance immunosuppression after lung transplantation was associated with a significantly lower prevalence in PPD-specific T-cell reactivity compared with renal transplant recipients (16.7% versus 52.1%; p = 0.0005). In line with the observations made in vivo, calcineurin inhibitors analysed in vitro led to a dose-dependent decrease in antigen-specific T-cell reactivity. The flow cytometric assay is not adversely affected by low drug doses. In contrast, decreased levels of PPD-specific T-cells early after transplantation and low prevalence of PPD-reactivity in lung transplant recipients suggest a reduced sensitivity of in vitro testing during high-level immunosuppression.

Risk factors for chronic thromboembolic pulmonary hypertension.

Chronic thromboembolic pulmonary hypertension (CTEPH) is characterised by nonresolving pulmonary thromboemboli that can be treated by surgical pulmonary endarterectomy (PEA). The authors of the present study sought to confirm known and to identify novel CTEPH risk factors in a controlled retrospective cohort study of prevalent CTEPH cases collected in three European centres offering PEA. Data from CTEPH patients were compared with nonthromboembolic pre-capillary pulmonary arterial hypertension cohorts at the participating institutions. The study population comprised 687 patients assessed at the time of diagnosis between 1996 and 2007. Ventriculo-atrial shunts and infected pacemakers (odds ratio (OR) 76.40, 95% confidence interval (CI) 7.67-10,351), splenectomy (OR 17.87, 95% CI 1.56-2,438), previous venous thromboembolism (VTE; OR 4.52, 95% CI 2.35-9.12), recurrent VTE (OR 14.49, 95% CI 5.40-43.08), blood groups other than 0 (2.09, 95% CI 1.12-3.94), and lupus anticoagulant/antiphospholipid antibodies (OR 4.20, 95% CI 1.56-12.21) were more often associated with CTEPH. Thyroid replacement therapy (OR 6.10, 95% CI 2.73-15.05) and a history of malignancy (OR 3.76, 95% CI 1.47-10.43) emerged as novel CTEPH risk factors. In conclusion, the European database study confirmed previous knowledge of chronic thromboembolic pulmonary hypertension risk factors, and identified thyroid replacement therapy and a history of malignancy as new medical conditions associated with chronic thromboembolic pulmonary hypertension.

Heparin-protamine does not aggravate local LPS-provoked leukocytic inflammation in vivo.

OBJECTIVE: Secondary complications involving inflammation limit postoperative results in cardiac surgery. Because heparin-protamine can elicit inflammatory reactions, this study evaluates in vivo whether treatment with heparin-protamine aggravates local endotoxin-induced injury. METHODS: Mice received intravenous injections of either heparin-protamine, protamine alone or PBS for controls, before local air pouch challenge with LPS. Leukocytes recruited within the air pouches were collected and analyzed by flow cytometry. RESULTS: LPS provoked a local leukocytic infiltration in a dose- and time-dependent manner with significantly elevated numbers of 1.75 +/- 0.29 x 10 (6) cells after four hours compared to non-LPS-stimulated controls (0.55 +/- 0.08 x 10 (6) cells). Recruited cells comprised of 74 +/- 4 % PMNLs and 26 +/- 4 % MNLs. The largest fraction of MNLs was positive for the T cell-specific marker CD90.2 (59 +/- 6 %). B cells were only rarely observed (4 +/- 1 %). In non-LPS-challenged air pouches, heparin-protamine provoked a leukocytic infiltration, which was comparable to that observed after LPS (1.51 +/- 0.22 x 10 (6) cells). However, neither heparin-protamine nor protamine alone aggravated the LPS-mediated leukocyte recruitment (2.25 +/- 0.25 x 10 (6) and 1.77 +/- 0.23 x 10 (6) cells). Neither treatment influenced the distribution of leukocyte subpopulations compared to PBS-treated controls. Furthermore, surface expression of CD11a and CD11b on blood leukocytes did not differ between the groups, indicating that protamine does not increase the activation of circulating leukocytes during LPS-induced local inflammation. CONCLUSIONS: Our data indicate that heparin-protamine, although pro-inflammatory in nature, does not aggravate local inflammation provoked by LPS. Thus, enhanced inflammation during the perioperative course of cardiac surgery patients seems not to be attributable to the intraoperative use of heparin-protamine.