Plasma-functionalized electrospun matrix for biograft development and cardiac function stabilization.

Cardiac tissue engineering approaches can deliver large numbers of cells to the damaged myocardium and have thus increasingly been considered as a possible curative treatment to counteract the high prevalence of progressive heart failure after myocardial infarction (MI). Optimal scaffold architecture and mechanical and chemical properties, as well as immune- and bio-compatibility, need to be addressed. We demonstrated that radio-frequency plasma surface functionalized electrospun poly(ɛ-caprolactone) (PCL) fibres provide a suitable matrix for bone-marrow-derived mesenchymal stem cell (MSC) cardiac implantation. Using a rat model of chronic MI, we showed that MSC-seeded plasma-coated PCL grafts stabilized cardiac function and attenuated dilatation. Significant relative decreases of 13% of the ejection fraction (EF) and 15% of the fractional shortening (FS) were observed in sham treated animals; respective decreases of 20% and 25% were measured 4 weeks after acellular patch implantation, whereas a steadied function was observed 4 weeks after MSC-patch implantation (relative decreases of 6% for both EF and FS).

Management of aortic aneurysms in patients with connective tissue disease.

Acute dissection and rupture of aortic aneurysms comprise for 1-2% of all deaths in developed countries. Dilation of the aorta is caused by several different mechanisms including inherited disorders of connective tissue. Recent reports estimate that 20% of patients presenting with thoracic aortic disease do have an underlying genetic basis of disease.

Fine-tuning of substrate architecture and surface chemistry promotes muscle tissue development.

Tissue engineering has been increasingly brought to the scientific spotlight in response to the tremendous demand for regeneration, restoration or substitution of skeletal or cardiac muscle after traumatic injury, tumour ablation or myocardial infarction. In vitro generation of a highly organized and contractile muscle tissue, however, crucially depends on an appropriate design of the cell culture substrate. The present work evaluated the impact of substrate properties, in particular morphology, chemical surface composition and mechanical properties, on muscle cell fate. To this end, aligned and randomly oriented micron (3.3±0.8 µm) or nano (237±98 nm) scaled fibrous poly(ε-caprolactone) non-wovens were processed by electrospinning. A nanometer-thick oxygen functional hydrocarbon coating was deposited by a radio frequency plasma process. C2C12 muscle cells were grown on pure and as-functionalized substrates and analysed for viability, proliferation, spatial orientation, differentiation and contractility. Cell orientation has been shown to depend strongly on substrate architecture, being most pronounced on micron-scaled parallel-oriented fibres. Oxygen functional hydrocarbons, representing stable, non-immunogenic surface groups, were identified as strong triggers for myotube differentiation. Accordingly, the highest myotube density (28±15% of total substrate area), sarcomeric striation and contractility were found on plasma-coated substrates. The current study highlights the manifold material characteristics to be addressed during the substrate design process and provides insight into processes to improve bio-interfaces.

Quality of life after acute type B dissection in the era of thoracic endovascular aortic repair.

BACKGROUND: Conservative management of acute type B aortic dissection is currently being challenged by primary thoracic endovascular aortic repair. Aim was to assess outcome and quality of life after these different approaches using an adjusted standard population as benchmark. PATIENTS AND METHODS: Observational study of a prospectively collected (January 2000 to December 2005) consecutive series of 87 patients with acute type B aortic dissection. Patients were 63 +/- 13 years old and 68 were men (78.2 %). Seventy-two were managed conservatively (83 %) and 15 invasively (12 by endovascular aortic repair). Follow-up was 36 +/- 19 months. Endpoints were early and late morbidity and mortality, and long-term quality of life as assessed by the Short Form health survey questionnaire. RESULTS: Patient cohorts were similar regarding age, risk profile and local disease. In the conservative cohort, four patients died during early (5.6 %) and eight during long-term follow-up (cumulative four years survival rate 79 %). Thirty-two patients needed secondary surgical management (44 %), i.e. delayed aortic repair (n = 11), or interventions on adjacent aortic sections or major branches (n = 21). In the surgical cohort no patient died, and no repeated interventions were necessary after the peri-operative period. Long-term quality of life scores were 100 (69-115) in conservatively and 94 (75-124) in invasively managed patients. Normal scores range from 85 to 115. CONCLUSIONS: Primary endovascular management of uncomplicated acute type B dissection is safe and leads to excellent long-term results, whereas secondary interventions were required with high incidence after initial conservative management. Long-term quality of life, however, returned to normal with any successful treatment strategy.

Acute pulmonary embolectomy three days following a coronary artery bypass graft procedure.

Pulmonary embolism is very rarely reported early after cardiac surgery, most probably due to full heparinisation during cardiopulmonary bypass. We report a 66-year-old man without thromboembolic history who presented three days after a coronary artery bypass grafting procedure with acute dyspnoea and haemodynamic instability. A CT scan confirmed paracentral bilateral pulmonary embolism requiring an urgent and successful embolectomy. Review of the literature confirms that pulmonary embolism may occur in up to 3% of post-cardiopulmonary bypass patients. The possibility of pulmonary embolism must be taken into consideration in post-cardiopulmonary bypass patients with acute onset of chest pain and respiratory insufficiency.

Soluble type A substance in fresh-frozen plasma as a function of ABO and Secretor genotypes and Lewis phenotype.

Soluble ABO blood group substance (SAS) in fresh-frozen plasma (FFP) and its cognate alloantibody titer reduction capacity (TRC) are not considered when prescribing this product for plasma exchange (PEX) therapy of ABO incompatible transplant recipients. SAS was quantified in 250 single FFPs using ELISA. Total and IgG class-specific anti-A TRCs of FFPs were measured using a microhemagglutination inhibition assay. SAS level depended not only on the A subtype (p < 0.0001) and the Secretor status (p < 0.0001), but also on the expression of ALe(b) in A1 secretors (p < 0.0001). The variation was as great as 137.6 arbitrary units (aU) for 14 A1 Le(a-b-) secretors and 1.2 aU for 6 A2 non-secretors. Homozygous expression of the A1, A2 and Secretor alleles did not increase SAS levels. Only total anti-A TRC, but not IgG class-specific TRC depended on the detected SAS level (r = 0.566, p = 0.0003).

Spontaneous dissection of common iliac artery. A case report.

Spontaneous dissection of the iliac artery is very rare but known as a complication of high-energy traumatic injuries and has been reported in connection with pregnancy, collagen diseases, and alpha-1-antitrypsin deficiency. The authors report a 42-year-old man with an acute dissection of the common iliac artery during exercise. Groin pain and claudication were the early symptoms. Computerized angiotomography was diagnostic. Operative iliac artery reconstruction was performed. A prerelease control computed tomography examination showed a dissection of the distal aorta and left iliac artery. To their knowledge, the combination of the 2 dissections has not been previously published.

Bovine mesenteric vein graft (ProCol) in critical limb ischaemia with tissue loss and infection.

OBJECTIVES: Poor results have been reported following infrainguinal reconstructions using heterogenous grafts. The objective of this study was to assess the use of bovine mesenteric vein (ProCol) graft in patients with critical limb ischaemia (CLI), tissue loss/infection and no autologous vein available for reconstruction. METHODS: Prospective analysis of 32 patients with CLI and tissue loss/infection, in whom reconstruction with ProCol was undertaken between October 1999 and May 2002. RESULTS: The primary patency rate was 16% at 1 month. After thrombectomy, the secondary patency rate was 50% at 1 month and 26% at 14 months. No graft infections were seen. Aneurysmal dilatation of the graft occurred in 2 (6%). Limb salvage at 14 months was 47%. CONCLUSION: In patients with critical limb ischaemia, tissue loss/infection and no available vein, the ProCol graft may be an alternative. However, primary patency is a problem. In situations without tissue loss/infection, where the risk of graft infection is less, prosthetic material may be a better alternative.

[The Sorin pericardial bioprosthesis--a stentless aortic valve with very good hemodynamic performance]. / Die Sorin Perikard-Bioprothese--eine Stentless Aortenklappe mit sehr guter hämodynamischer Leistung.

BACKGROUND: The Sorin Pericarbon Freedom Stentless aortic valve has the potential to provide superior hemodynamic function and durability. In this study we assessed the hemodynamic performance of this valve and its impact on LV-mass regression after aortic valve replacement. METHODS: 31 consecutive patients who received a Sorin Pericarbon Freedom Stentless aortic valve were analysed. Mean age of the patients (16 female and 15 male) was 64 +/- 17 years. Five patients had isolated aortic stenosis, three isolated aortic regurgitation and one combined aortic valve disease. Three patients had combined aortic and mitral valve disease, 14 patients concomitant coronary artery disease, one congenital aortic coarctation. Three patients had an acute aortic valve endocarditis. 18 patients were classified as high-risk patients (mean EuroSCORE 9 +/- 2). Mean left ventricular ejection fraction was 52.5 +/- 15.0%. RESULTS: Valve sizes from 21 mm to 29 mm were implanted. The valves were oversized by 2 mm compared to measurement. 16 patients received isolated aortic valve replacement, Three patients aortic valve replacement and mitral valve reconstruction. 12 patients had concomitant CABG. Three procedures were reoperations. Hospital mortality was 6.4% (two patients). Both deaths occurred in high-risk patients and were not valve-related. Four patients had perioperative low-output-syndrome and needed IABP. After six months a follow up echocardiography was performed. Mean and peak gradients were 9.6 +/- 4.4 and 20.6 +/- 5.9 mmHg, respectively. Significant reduction of left ventricular hypertrophy (LV mass index 126.5 +/- 27.3 vs. 189.6 +/- 45.3 g/m2, p = 0.0313) and improvement of the ejection fraction (58 +/- 9.8 vs. 52.5 +/- 15.0%, p = 0.9749) as compared with preoperative valve. CONCLUSIONS: The hemodynamic performance of the Sorin Pericarbon Freedom Stentless aortic valve is excellent and the patient outcome is satisfying. However the implantation technique requires longer ischemic time, the prosthesis offers very satisfying hemodynamic function and accelerates probably the LV-mass regression in the mid term follow-up. Late performance and durability of the valve have to be assessed.

Common femoral artery--uncommon aneurysms.

BACKGROUND AND AIMS: Femoral artery aneurysms are rare. Their natural history, tendency to embolize or rupture are not well known. MATERIAL AND METHODS: Data of all patients seen 1996-2002 with femoral artery aneurysms at the Swiss Cardiovascular Center were analysed. Nine patients with 13 aneurysms of the common femoral artery (CFA) were identified. Only true aneurysms with a diameter of at least 2.5 cm were included. All patients were male, mean age 70 years (range: 57-85 years). Four patients had bilateral femoral aneurysms. Risk factors included hypertension (9/9), smoking (7/9). One of the aneurysms was palpable in 5/9. Four patients were asymptomatic, 5 had Fontaine class II claudication. Five patients also had an aortic aneurysm (AAA), one a thoracic aneurysm; and 6/9 popliteal aneurysms. In all patients, diagnosis was confirmed with duplex scan. Angiography was performed preoperatively. RESULTS: The aneurysms were operated on electively using aneurysm secclusion and interposition grafting. There were no significant perioperative complications. Median hospital stay was 8 days. CONCLUSION: CFA aneurysms are rare. They are palpable in nearly half of the cases. They rarely cause thrombotic or embolic complications, but are almost always connected to other aneurysms. Patients with CFA aneurysms should be screened with duplex scan. Operative therapy is straightforward, few complications can be expected. Postoperative follow-up with annual duplex scans is suggested.

Association of ABO histo-blood group B allele with myocardial infarction.

To investigate a possible association of ABO blood group alleles with myocardial infarction, a case-control study comprising 177 patients (median age 57.0 years; range 32-72 years) and 89 controls was performed. The distributions of the ABO blood-genotype O1, O2, A1, A2 and B alleles were assessed by analysis of genomic DNA, using the sequence-specific primer-polymerase chain reaction (PCR-SSP) technique to investigate exons VI and VII on chromosome 9. The prevalence of the B allele was 2.5 times higher amongst patients with a history of myocardial infarction than amongst controls (16.3 vs. 6.7%; P = 0.034, Fisher's exact test). There was an association between patients carrying the B allele and myocardial infarction, with an odds ratio (OR) of 2.7 (95% confidence interval 1.1-6.8). The B allele remained an independent risk factor for myocardial infarction (P = 0.038) when classical risk factors were adjusted for by unconditional logistic regression. In conclusion, the ABO blood group B allele was found to be an independent risk factor for myocardial infarction.

Aprotinin reduces blood loss in off-pump coronary artery bypass (OPCAB) surgery.

OBJECTIVE: Effects of aprotinin in off-pump coronary artery bypass (OPCAB) surgery have not yet been described. This study analyses hemostasiologic changes and potential benefit in OPCAB patients treated with aprotinin. METHODS: In a prospective, double-blind, randomized study 47 patients undergoing OPCAB surgery were investigated. Patients received either aprotinin (2 x 10(6) KIU loading dose and 0.5 x 10(6) KIU/h during surgery, n=22) or saline solution (control, n=25). Activated clotting time was adjusted to a target of 250 s intraoperatively. Blood samples were taken up to 18h postoperatively: complete hematologic and hemostasiologic parameters including fibrinopeptide A (FPA) and D-dimer in a subgroup of 31 patients were analyzed. Blood loss, blood transfusion and other clinical data were collected. RESULTS: Both groups showed comparable demographic and intraoperative variables. Forty-one (87%) patients of the whole study group received aspirin within 7 days prior to surgery. Number of grafts per patient were comparable (2.9+/-1.0 [mean+/-SD] in the aprotinin group and 2.8+/-1.2 in control, P=0.83). Blood loss during the first 18 h in intensive care unit was significantly reduced in patients treated with aprotinin (median [25th-75th percentiles]: 500 [395-755] ml vs. 930 [800-1170] ml, P<0.001). Postoperatively only two patients (10%) in the aprotinin group received packed red blood cells, whereas eight (35%) in the control group (P=0.07). Perioperatively FPA levels reflecting thrombin generation were elevated in both groups. The increase in D-dimer levels after surgery was significantly inhibited in the aprotinin group (P<0.001). Early clinical outcome was similar in both groups. CONCLUSIONS: Aprotinin significantly reduces blood loss in patients undergoing OPCAB surgery. Inhibition of enhanced fibrinolysis can be observed. FPA generation during and after OPCAB surgery seems not to be influenced by aprotinin.

Isolated amelanotic malignant melanoma of the heart.

We report a 58-year-old woman presenting with dyspnoea and recurrent pulmonary embolism. Echocardiography revealed pericardial effusion and a tumour located in the atrioventricular groove. Surgical exploration showed tumorous infiltration of the ventricle wall and of parts of the atrium. Curative excision was not possible and the operation was discontinued. Histology revealed an amelanotic malignant melanoma. No other tumour location was detected by scanning procedures. This case represents a very rare manifestation of melanoma exclusively located in the atrioventricular groove of the heart leading to recurrent pulmonary embolism. A review of the literature on cardiac involvement of melanoma is provided.

Minimizing aortic manipulation during OPCAB using the symmetry aortic connector system for proximal vein graft anastomoses.

BACKGROUND: Since minimal invasive techniques have become increasingly common in coronary artery bypass grafting (CABG), there has been renewed interest in facilitated mechanical anastomoses devices that might have the potential of replacing the standard suturing techniques in vascular anastomoses. We report our initial experience with the successful creation of mechanical proximal vein graft anastomoses in off-pump coronary artery bypass operations. METHODS: From August to December 2000, we investigated the first 20 consecutive patients who underwent CABG on the beating heart without extracorporeal circulation and who received at least one mechanical proximal vein graft anastomosis with the St. Jude Medical Symmetry aortic connector system without side-clamping of the aorta. We evaluated the different components of the system, the feasibility of such anastomoses, and the intraoperative flow measurements of the grafts using transit time methods. RESULTS: A total of 32 proximal vein graft anastomoses were performed with the aortic connector system. Hemostasis was instantaneous in all cases except one, in which the connector was removed and the anastomosis was hand-sewn without complications. All other vein grafts were patent at the end of the procedure; intraoperative flow measurements were 39 +/- 25 mL/min for single vein grafts (n = 20) and 69 +/- 25 mL/min for sequential grafts (n = 11). CONCLUSIONS: The St. Jude Medical Symmetry aortic connector system is a user-friendly, effective, quick, and reliable device for sutureless proximal vein graft anastomosis in CABG. This system allows the construction of uniform and geometrically perfect anastomoses and does not require aortic side-biting. This technology is attractive for all CABG procedures because aortic manipulation is reduced. In off-pump surgical procedures the connector system allows aortic manipulation to be minimized, potentially reducing embolization from aortic wall debris.

Pneumonia after cardiac surgery is predictable by tracheal aspirates but cannot be prevented by prolonged antibiotic prophylaxis.

BACKGROUND: The purpose of this study was to assess the value of tracheal aspirate as a predictor of pneumonia after coronary artery bypass grafting and to evaluate the efficacy of prolonged perioperative antibiotic prophylaxis. METHODS: Tracheal aspirates of 500 patients undergoing coronary artery bypass grafting were taken immediately after intubation and analyzed for microorganisms by Gram stain and semiquantitative microbiologic cultures. All patients received 2 g ceftriaxone as a single-dose perioperative antibiotic prophylaxis before operation. Results of Gram stains were available before the patients were transferred to the intensive care unit. After the results were known, both groups of patients (positive Gram stain, group 1; negative Gram stain, group 2) were randomly assigned to either conventional antibiotic prophylaxis (A), consisting of ceftriaxone 2 g on postoperative day 1, or prolonged antibiotic prophylaxis (B), with ticarcillin + clavulanic acid 3 x 5.2 g during 72 hours. RESULTS: From 500 patients, 91 had a positive Gram stain whereas 409 had a negative one. The incidence of pneumonia was significantly higher in patients with preoperative positive tracheal aspirates (15.3%) than in patients with a negative one (3.6%; p < 0.01). However, prolonged prophylaxis did not reduce the rate of postoperative pneumonia, which was as high as 13% in untreated positive patients versus 17% in treated positive patients, and 2% in untreated negative patients versus 4% in treated patients. In patients who had pneumonia, there was a high correlation between the microorganisms found in preoperative aspirates and those observed when aspirates were repeated (100% correlation in patients with conventional antibiotic prophylaxis and 87% in those with prolonged prophylaxis). CONCLUSIONS: Early postoperative pneumonia (<7 days) is most likely caused by microorganisms that colonize the respiratory tract before operation. The risk of pulmonary infection after coronary artery bypass grafting can be predicted from the preoperative tracheal aspirates. Prolonged perioperative antibiotic prophylaxis has no efficacy in reducing the incidence of pulmonary infections.

Constrictive tuberculous pericarditis in a HIV-positive patient.

Constrictive pericarditis is a relatively rare clinical manifestation nowadays. We present the case of an HIV-positive patient with constrictive calcified pericarditis due to an infection with Mycobacterium tuberculosis. Pericardectomy was performed. The therapeutical approach is discussed and the literature is reviewed.

Sutureless mechanical anastomosis of a saphenous vein graft to a coronary artery with a new connector device.

Construction of vascular anastomoses by manual suturing is a highly skilled and time-consuming procedure. The St Jude Medical Anastomotic Technology Group has developed a sutureless mechanical anastomosis device, which, when tested in animals, produced anastomoses in less than 3 min and with little training. Here we present the results of the first clinical saphenous-vein to coronary-artery anastomosis by means of this device.

Modified repair of mixed total anomalous pulmonary venous connection.

Mixed total anomalous pulmonary venous connection (TAPVC) is a rare condition, accounting for only 5% of diagnosed TAPVC. It is associated with a poor prognosis unless surgically corrected by connecting the pulmonary venous sinus to the left atrium and optionally dividing the abnormal connection to the systemic venous system. We report a modified technique of complete intracardiac repair of mixed supracardiac and cardiac TAPVC in a 3-year-old child without pulmonary venous sinus-to-left atrium anastomosis.