Ovine blood: establishment of a list of reference values relevant for blood coagulation in sheep.

Ovine animal models are widely used to conduct preclinical studies, e.g., to evaluate cardiovascular prostheses intended to be applied in man. However, although analyzed in many of those studies, information about ovine blood reference values is scanty. The aim of this study is to establish a reference list of ovine blood parameters relevant for blood coagulation. A cohort of 47 mature ewes was evaluated. Parameters comprised the following: cells and cellular components-platelet, red, and white cell counts (including subsets), hemoglobin (Hb), hematocrit (HCT), mean corpuscular hemoglobin (MCH) and mean corpuscular volume (MCV), and MCH concentration (MCHC); global tests of coagulation-prothrombin time (Quick's time) and activated partial thromboplastin time (aPTT); and parameters relevant for blood coagulation-fibrinogen, antithrombin (AT), and von Willebrand Factor. After explorative data analysis, a list of ovine reference values was established. Interestingly, a comparison with human reference values revealed some interspecies differences between sheep and man, i.e., much higher ovine ranges for some cell counts (neutrophils, lymphocytes, basophils, eosinophils, and platelets) but lower values for some other parameters (Hb, HCT, MCV, MCH, AT, and Quick's test). We established a reference list of ovine blood count and blood coagulation parameters. Because of some peculiarities of the ovine blood, this list may have implications for the interpretation of experimental data.

Contralateral internal carotid artery occlusion impairs early but not 30-day stroke rate following carotid endarterectomy.

Neurological complications and mortality within 30 days following carotid endarterectomy (CEA) alone or with concomitant cardiac surgery/cardiopulmonary bypass (CPB) were assessed in patients with or without contralateral occlusion of the internal carotid artery (CO-ICA).Of 335 patients undergoing CEA, 173 underwent concomitant cardiac surgery with CPB. Group A consisted of 260 patients without CO-ICA and group B of 75 patients with CO-ICA. The neurological complications (peripheral nerve damage, transient ischemic attack [TIA], prolonged reversible ischemic neurological deficit [PRIND], and stroke) and the Rankin index within 24 hours and 30 days postoperatively were compared. Strokes within 24 hours were significantly increased (P = .006) in group B (11%) compared with A (3.1%); TIA and PRIND did not differ (P = .33). The overall neurological complications and in particular for peripheral neurological damage, TIA/PRIND, and stroke did not differ within the 30-day-period postsurgery. A significantly higher stroke rate within 24 hours postsurgery occurred in patients with CO-ICA.

High resolution computed tomography imaging for individualized allograft replacement of an infected Dacron aortic arch prosthesis.

We report on the case of a young woman with a history of intravenous drug abuse and the development of an infection of a prosthetic supracoronary-, total arch and partial descending aortic allograft prosthesis following acute aortic dissection type Stanford-A two years previously. For surgical treatment we implanted an allograft prosthesis obtained from a local tissue bank. Particular variations in this setting and in comparison to conventional surgical planning were that high resolution computed tomography imaging was applied to determine and subsequently order the optimal allograft prosthesis in this individual patient and anatomical situation.

Long-term cardiac allograft valves after heart transplant are functionally and structurally preserved, in contrast to homografts and bioprostheses.

BACKGROUND AND AIM OF THE STUDY: Homograft valves undergo degenerative changes over time, which finally lead to functional deterioration. Immunological events are believed to play a pivotal role in this process. To further evaluate this hypothesis, the valvular morphology and function, as well as comorbidities predisposing to deteriorative processes, were evaluated in patients who had undergone heart transplant more than 10 years previously. METHODS: In a consecutive cohort of 146 patients (125 males, 21 females; mean age at transplant 43.8 +/- 11.2 years), heart and valve function were assessed by color Doppler echocardiography at a mean of 5306 +/- 987 days after heart transplant. Evaluated parameters included chamber dimensions, cardiac function, valvular morphology/function, and concomitant diseases. RESULTS: Atrial and ventricular dimensions were within normal ranges for the left atrium (LA; n=7), right atrium (RA; n=7), left ventricle (LV; n=143) and right ventricle (RV; n=119). Slight enlargements occurred in the LA (n=138), RA (n=137), LV (n=1) and RV (n=11), while significant enlargements were seen in the LA (n=1), RA (n=2), LV (n=2), and RV (n=16). With regard to cardiac function, the ejection fraction (EF) was 63.9 +/- 4.9%, left ventricular isovolumic relaxation time (IVRT) 85.04 +/- 14.64 ms, fractional shortening (FS) 34 +/- 12%, and pulmonary artery systolic pressure (PASP) 29.81 +/- 6.4 mmHg. Valvular regurgitation (grade > or =2) was present in 34 patients (31 tricuspid valves, three mitral valves). No patients presented with aortic valve regurgitation. Concomitant conditions with a potential impact on calcium balance/valvular deterioration included immunologic/chronic inflammatory diseases (n=6), malignancies (n=12), kidney (n=41), cardiovascular system (n=39) and thyroid/parathyroid (n=12). CONCLUSION: During the long term after heart transplant, heart valves were characterized by normal morphology and function in the majority of cases. Although most patients presented with concomitant conditions strongly predisposing for valvular deterioration/calcification, sole immunosuppressive/anti-inflammatory therapy appears to prevent these processes in heart transplant patients.

Upregulation of endothelial adhesion molecules in hearts with congestive and ischemic cardiomyopathy: immunohistochemical evaluation of inflammatory endothelial cell activation.

OBJECTIVE: In recent years many data emphasized, that inflammatory reactions seem to be involved in the pathogenesis of ischemic (ICM) and congestive (CCM) heart disease. Since, it is well known that endothelial adhesion molecules play a pivotal role in the initiation and maintenance of inflammatory reactions we therefore, evaluated the endothelial expression of a wide variety of different adhesion molecules in hearts suffering from ICM and CCM. METHODS: Tissue samples from coronary arteries, and left and right ventricle myocardium originating form heart with ICM and CCM were evaluated. Tissue samples from healthy human donor hearts, which were not transplanted, served as controls. Evaluated adhesion molecule expression: selectin-family ELAM-1, CD62, immunoglobulin-supergene-family PECAM-1, ICAM-1, VCAM-1, integrin-family VLA-1,-2,-3,-4,-5, and -6, complementary-adhesion-molecules CD34, CD44 and the von-Willebrand-factor (vWF). RESULTS: While endocardial surfaces and coronary arteries revealed only little differences when comparing tissue samples originating from healthy donor hearts and those suffering from ICM and CCM, significant differences were found within the myocardial microvasculature. Both kinds of diseased hearts showed stronger expressions for CD62, ELAM-1, ICAM-1 and VCAM-1 (only CCM) than controls. More and above, integrin molecules showed differential expressions too. Whereas, VLA-1 showed stronger expressions in diseased hearts, VLA-3,-5, and -6 were expressed much weaker in those hearts. Complementary adhesion molecules (CD34/CD44) did not show significant differences and the vWF was not found in any sample. CONCLUSIONS: Inflammatory reactions play a pivotal role in the propagation and maintenance of both these cardiac detoriating diseases.

Role of inflammation in allogeneic and xenogeneic heart valve degeneration: immunohistochemical evaluation of inflammatory endothelial cell activation.

BACKGROUND AND AIM OF THE STUDY: Biological heart valve prostheses undergo degenerative changes which lead ultimately to dysfunction or even complete destruction. The study aim was to evaluate immunological factors and their potential role in biological heart valve destruction. METHODS: Allogeneic (n = 10) and xenogeneic (n = 3) aortic valve prostheses, as well as aortic valves retrieved from transplanted human hearts which had to be replaced due to chronic graft rejection (n = 4), were analyzed. Aortic valves from human donor hearts (n = 4) served as controls. Evaluated adhesion molecule expression included: selectin family ELAM-1, CD62; integrin family VLA-1, -2, -3, -4, -5 and -6; immuoglobulin supergene family PECAM-1, ICAM-1 and -2, and class I heavy chain proteins; complementary adhesion molecules CD34, CD44 and von Willebrand factor. RESULTS: ELAM-1, ICAM-1 and -2, CD34, CD44 and class I heavy chain proteins, which play significant roles during inflammatory processes, showed stronger expression patterns in allogeneic and xenogeneic aortic heart valve prostheses compared to native or chronically rejected valves. Furthermore, allogeneic and xenogeneic valves showed a strong thrombogenicity which stained positive for von Willebrand factor outside endothelial cells on these valves. Integrin molecules as well as CD62 showed only mild differences. CONCLUSION: Immunological reactions play a pivotal role in the degeneration of biological heart valve prostheses. As immunosuppressive therapy after heart valve replacement is not a viable option, novel approaches in 'tissue engineering' may help to avoid tissue degeneration while preserving the advantage of biological tissue origin.