Atrial fibrillation and rapid acute pacing regulate adipocyte/adipositas-related gene expression in the atria.

PURPOSE: Atrial fibrillation (AF) has been associated with increased volumes of epicardial fat and atrial adipocyte accumulation. Underlying mechanisms are not well understood. This study aims to identify rapid atrial pacing (RAP)/AF-dependent changes in atrial adipocyte/adipositas-related gene expression (AARE). METHODS: Right atrial (RA) and adjacent epicardial adipose tissue (EAT) samples were obtained from 26 patients; 13 with AF, 13 in sinus rhythm (SR). Left atrial (LA) samples were obtained from 9 pigs (5 RAP, 4 sham-operated controls). AARE was analyzed using microarrays and RT-qPCR. The impact of diabetes/obesity on gene expression was additionally determined in RA samples (RAP ex vivo and controls) from 3 vs. 6 months old ZDF rats. RESULTS: RAP in vivo of pigs resulted in substantial changes of AARE, with 66 genes being up- and 53 down-regulated on the mRNA level. Differential expression during adipocyte differentiation was confirmed using 3T3-L1 cells. In patients with AF (compared to SR), a comparable change in RA mRNA levels concerned a fraction of genes only (RETN, IGF1, HK2, PYGM, LOX, and NR4A3). RA and EAT were affected by AF to a different extent. In patients, concomitant disease contributes to AARE changes. CONCLUSIONS: RAP, and to lesser extent AF, provoke significant changes in atrial AARE. In chronic AF, activation of this gene panel is very likely mediated by AF itself, AF risk factors and concomitant diseases. This may facilitate the development of an AF substrate by increasing atrial ectopic fat and fat infiltration of the atrial myocardium.

Early-onset and persisting thrombocytopenia in post-cardiac surgery patients is rarely due to heparin-induced thrombocytopenia, even when antibody tests are positive.

BACKGROUND: The high frequency of thrombocytopenia in post-cardiac surgery patients makes it challenging to diagnose heparin-induced thrombocytopenia (HIT). Two platelet count profiles are reported as indicating possible HIT in these patients: profile 1 describes a platelet count fall that begins between postoperative days 5 and 10, whereas profile 2 denotes early-onset thrombocytopenia that persists beyond day 5. OBJECTIVES: To examine how these platelet count profiles correlate with antibody status and HIT post-cardiac surgery. METHODS: We prospectively screened 581 cardiac surgery patients for heparin-dependent antibodies by platelet factor 4 (PF4)-heparin immunoassay and platelet-activation test, and performed daily platelet counts (until day 10) with 30-day follow-up. RESULTS: All three patients with platelet count profile 1 tested positive for platelet-activating anti-PF4-heparin IgG antibodies [odds ratio (OR) 521.7, 95% confidence interval (CI) 3.9-34,000, P = 0.002], and were judged to have HIT. In contrast, none of 25 patients with early-onset and persisting thrombocytopenia (profile 2) was judged to have HIT, including five patients testing positive for platelet-activating anti-PF4-heparin IgG antibodies. In these patients, the frequency of heparin-dependent antibodies did not differ from that in non-thrombocytopenic controls, either for anti-PF4-heparin IgG (OR 1.7, 95% CI 0.7-4.1, P = 0.31) or for platelet-activating antibodies (OR 1.9, 95% CI 0.6-5.7, P = 0.20). Multivariate analysis revealed that type of cardiac surgery, but not HIT antibody status, predicted early-onset and persisting thrombocytopenia. Together, these findings show that HIT was uncommon in this study population [overall frequency, 3/581 (0.5%), 95% CI 0.1-1.5%]. CONCLUSIONS: Thrombocytopenia that begins between 5 and 10 days post-cardiac surgery is highly predictive for HIT. In contrast, early-onset and persisting thrombocytopenia is usually caused by non-HIT factors with coinciding heparin-dependent antibody seroconversion.

Management of emergency cardiac surgery in a patient with alloanti-Ge2.

Transfusion management of patients alloimmunized against high-prevalence erythrocyte antigens is often problematic in emergency situations. In these patients, incompatible transfusion may be less harmful for the patient than delaying surgery, especially if the antibody is not clinically significant. We report an untransfused 75-year-old Caucasian man (blood group O) with an alloantibody against the Gerbich-2 (Ge2) antigen who required emergency cardiac surgery. Because cross-match compatible blood was not available in an acceptable timeframe, we performed a 'biological cross-match' with sequential transfusion of 20 and 50 mL and then the entire unit of incompatible red blood cells (RBCs) before surgery. When there were no clinical symptoms of adverse biological effects, we transfused two further incompatible packed RBCs during surgery. Subsequently, there was neither clinical nor laboratory evidence of major intra- or extravascular haemolysis, suggesting that this anti-Ge2 antibody was not clinically significant.

[Pulmonary embolism caused by aspergillosis (so-called fungal embolism)]. / Lungenembolie durch Aspergillose (sog. Pilzembolie).

A 71-year-old man developed a cardiac tumour in the right ventricle and a pulmonary embolism caused by aspergillosis after implantation of a pacemaker because of arrhythmia. Repeated revisions during pocket infections. Emergency operation and tricuspid valve replacement with a Carpentier Edwards xenograft. The pacing electrodes and the endocardium were infected by Aspergillus in form of an aspergilloma. This case is an example of the rare condition of a pulmonary embolism with pure fungal material.

Heparin-induced thrombocytopenia in patients requiring prolonged intensive care unit treatment after cardiopulmonary bypass.

BACKGROUND: The diagnosis of heparin-induced thrombocytopenia (HIT) is problematic in postcardiac surgery (CS) intensive care unit (ICU) patients, as there are multiple potential explanations for thrombocytopenia and the presence of anti-platelet factor 4/heparin antibodies is not highly specific for HIT. Two platelet count profiles for HIT - a 40% or greater fall in platelet count beginning on or after day 5 (pattern 1) and persisting thrombocytopenia (< 100 x 10(9) L(-1)) beyond day 7 (pattern 2) - have been described in post-CS patients. METHODS AND RESULTS: We examined the platelet count profiles of 329 consecutive post-CS patients who required ICU treatment beyond 7 days. Although 70 patients (21.3%) developed thrombocytopenia (57.1% pattern 1, 42.9% pattern 2), the overall incidence of HIT was only 1.8% [6/329; 95% confidence interval (95% CI) 0.7-3.9%] in these ICU patients, with more HIT patients showing a pattern 2 than a pattern 1 platelet count decrease (four vs. two patients). Notably, pattern 2 patients with HIT also showed a new proportional fall of > 30% in platelet count between postoperative days 5 and 10. Among the remaining 2242 post-CS patients without a prolonged ICU stay, only three (0.1%; 95% CI 0.03-0.4%) developed symptomatic HIT (OR 0.07; 95% CI 0.01-0.3; P = 0.0002 vs. ICU patients), all presenting with pattern 1. CONCLUSIONS: Among post-CS ICU patients, a postoperative platelet count fall between days 5 and 10 increases diagnostic specificity for HIT, irrespective of whether this platelet count fall occurs after postoperative platelet count recovery (pattern 1) or is superimposed upon persisting postoperative thrombocytopenia (pattern 2). A prospective study is required in order to validate the findings of this retrospective analysis.

Sarcoma associated with silver coated mechanical heart valve prosthesis.

Sarcomas can develop in association with foreign material (eg, from Dacron vascular prostheses). We report on a left atrial rhabdomyosarcoma that developed within 1 year of mitral valve replacement by a Silzone-coated St. Jude Medical mechanical heart valve. Tumor resection and redo valve replacement were done. Six months later the patient was alive, but an echocardiogram showed tumor recurrence. Although this is a single case, an association between heart valve prostheses and malignant tumors should be considered.

Emergency coronary artery bypass grafting: does excessive preoperative anticoagulation increase bleeding complications and transfusion requirements?

Patients requiring urgent surgical revascularization due to unstable coronary artery disease are usually pretreated with multiple antithrombotic drugs. The perioperative risks of this type of treatment were investigated in 123 patients who underwent emergency coronary artery bypass grafting (CABG) at our institution.Eighty-two patients (group A) received heparin and acetylsalicylic acid solely and 41 patients (group B) received additionally ADP-receptor antagonists (82.9%), glycoprotein IIb/IIIa inhibitors (12.2%) or thrombolysis (14.6%) preoperatively. Both groups were similar regarding demographic data and overall clinical status. Preoperative coagulation parameters and intraoperative characteristics were comparable. Blood loss via chest tubes was not significantly different between groups. Transfusion of red blood cells and fresh frozen plasma were slightly, but not significantly increased in group B. Transfusion of pooled platelets was low in general and similar in both groups. Re-exploration rate, medium intensive care unit and hospital stay as well as perioperative mortality were comparable.Excessive antithrombotic pretreatment seems to bear no additional risk in emergency CABG and may be beneficial in this setting.

Emergency cardiopulmonary bypass in a bilaterally nephrectomized patient with a history of heparin-induced thrombocytopenia: successful reexposure to heparin.

We present a case of emergency coronary artery bypass surgery in a bilaterally nephrectomized patient with a history of heparin-induced thrombocytopenia. The patient was reexposed short term to heparin during cardiopulmonary bypass and did not develop any complications related to heparin-induced thrombocytopenia. Despite intraoperative neutralization of heparin severe bleeding complications occurred, probably resulting from preoperative therapeutic anticoagulation with rhirudin in conjunction with an increased half-life of more than 2 days.

Stunned myocardium after off-pump coronary artery bypass grafting.

Off-pump coronary artery bypass grafting is increasingly performed. Because these procedures are associated with temporary myocardial ischemia, there is a risk of ischemia-related complications. We report two cases of myocardial stunning after off-pump coronary artery bypass grafting using the Octopus tissue stabilizer. On the basis of our experiences, means to prevent stunning are discussed.

Pumpless arteriovenous extracorporeal lung assist: what is its role?

Extracorporeal lung assist (ECLA) is an established treatment of severe pulmonary failure. Since extracorporeal perfusion is applied in a long-term fashion in this setting, the negative impact on blood compounds is of tremendous importance. Pumpless arteriovenous ECLA (av-ECLA) is an alternatively introduced technique that focuses on reduced blood traumatization. However, due to determining technical and physiological aspects, its clinical application is limited to a highly selected group of patients. Membrane oxygenators with minimal pressure gradients, as well as stable patients' haemodynamics providing a sufficient cardiac output, are the most important prerequisites. With respect to recent reports, characteristic features of av-ECLA, with special emphasis on its physiological background, are reviewed. Accordingly, reasonable indications for its beneficial use are discussed. It is concluded that av-ECLA is a feasible technique when its limitations are accepted. For adequate clinical use, more data concerning indications, as well as time- and technique-related directions are required.

Anticoagulation in extracorporeal circulation using recombinant hirudin: a case report.

Heparin-induced thrombocytopenia (HIT) is a severe complication following the application of heparin; antibodies against complexes of heparin and PDF4 initiate activation of platelets. This may lead to massive thrombembolism, which is associated with a slight and transient drop of platelets in HIT I or a drop below 50% after approximately 5 days in HIT II. Further administration of heparin has to be strictly avoided in these patients. Immunologic evidence for HIT can easily be obtained by the heparin-induced platelet aggregation assay. If anticoagulation is necessary, different, alternative drugs are available. Recombinant hirudin (r-hirudin) is a well-established drug for safe anticoagulation. Monitoring is possible by estimating the plasma level of r-hirudin from the ecarin-clotting time. We report a case of a patient with prosthetic aortic valve endocarditis and HIT II who suffered from massive postoperative bleeding requiring massive substitution of blood components and coagulants caused by free circulating r-hirudin due to the use of a hemofilter.

Severe heart valve calcification in a young patient with Werner syndrome.

Werner syndrome is a rare autosomal recessive disorder characterized by the appearance of premature aging. We report on severe aortic and mitral valve calcification in an 18-year-old girl, necessitating double valve replacement. These special cardiovascular findings are discussed with regard to diagnosis and treatment.

Hemostasis management by use of Hepcon/HMS: increased bleeding without increased need for blood transfusion.

BACKGROUND: Extracorporeal circulation forces complete anticoagulation, most frequently achieved by complete heparinization. Activated clotting time (ACT) is the gold standard for monitoring, although there is a lack of correlation between heparin plasma level and ACT. Several systems for the estimation of free heparin have been developed: in this study we focused investigating on the influence of the Hepcon/HMS system on postoperative bleeding and transfusion requirements. METHODS: 114 patients were randomly assigned to one group monitored by use of Hepcon/HMS (group hepcon) and another group by use of ACT (ACT group); 7 patients were excluded due to re-exploration. 12 patients did not receive aprotinin; this part of the study was stopped early due to massive increased bleeding. 46 and 49 patients of groups hepcon and ACT, respectively, received aprotinin. RESULTS: Using aprotinin, in group hepcon total administered heparin was elevated by 13 % in contrast to group ACT while administered protamine was reduced by 20%. The ratio of antagonization was 82 +/- 17 % and 51 +/- 12 %, respectively. Coagulation parameters were not influenced except for increased postoperative ACT and PTT in the hepcon group. Bleeding of patients in that group was significantly increased during the first 6 hours, which led to an increased autologous retransfusion. Need for substitution of other blood components was not increased postoperatively. CONCLUSIONS: Use of the Hepcon/HMS-system for monitoring of heparinization during extracorporeal circulation is possible without increased risk of thromboembolism. Postoperative blood loss was slightly but significantly increased but there was no need for more heterogenous transfusion.