Geoffrey Tsang

von Willebrand factor and urinary albumin excretion are possible indicators of endothelial dysfunction in cardiopulmonary bypass

OBJECTIVE Experimental evidence suggests that cardiopulmonary bypass (CPB) associated inflammatory response leads to endothelial injury and increased permeability, but this has been difficult to show clinically. We have investigated the use of von Willebrand factor (vWF), and urinary albumin excretion, as measured by the urinary albumin creatinine ratio (ACR), to demonstrate this. METHODS A total of 23 patients undergoing elective coronary artery bypass grafting were studied. Complement fragment C3a, leukotrienne B4 (LTB4), interleukin 6 (IL6), neutrophil elastase, vWF and ACR were measured on anaesthetic induction (baseline), 20 min after starting CPB, 5 min after cross-clamp removal, 5 min, 2, 6 and 24 h after termination of CPB. Anaesthetic, CPB and myocardial protection techniques were standardised. ANOVA was performed by using the distribution free Friedman test for each measured parameter. When significance differences were found (P < 0.05), post hoc analysis with Wilcoxon signed rank test was used for comparison of each time point with the base line level and differences were only accepted as significant following the Bonferroni correction (P < 0.008). Summary measures of peak versus peak and area under the cure were also analysed for ACR with vWF. RESULTS Peak vs. baseline levels for C3a were 4.9 vs. 2.1 microg/ml (P < 0.0001), LTB4 was 800 vs. 20 pg/ml (P < 0.0001), neutrophil elastase was 250 vs. 115 ng/ml (P < 0.001), IL6 was 620 vs. 1.4 pg/ml (P < 0.0001), vWF was 2.2 vs. 1.3 IU/ml (P < 0.0001) and ACR was 17.6 vs. 2.0 mg/mmol (P < 0.0001). C3a, LTB4 and ACR peaked during the operation. Neutrophil elastase peaked at 2 h following CPB. IL6 and vWF peaked at 6 h following CPB. The correlation coefficient between vWF and ACR following peak versus peak analysis was 0.48 (P = 0.035), and area under the curve analysis was 0.6 (P < 0.01). CONCLUSION These results demonstrate that endothelial permeability and injury, as measured by urinary albumin excretion and vWF, respectively, are related and the use of these easily detectable and sensitive biochemical markers warrants further investigation.

Pentoxifylline Preloading Reduces Endothelial Injury and Permeability in Cardiopulmonary Bypass

Pentoxifylline (PTX), a methyl xanthine derivative, reduces endothelial permeability. A double blind, prospective, randomized, placebo controlled, parallel study was undertaken to assess the effect of PTX on leukotriene B4, complement fragment C3a, interleukin 6 (IL6), endothelial injury as measured by von Willebrand factor (vWf), and endothelial permeability as measured by urinary albumin excretion (expressed as excreted urinary albumin to creatinine ratio [ACR]) in patients undergoing cardiopulmonary bypass (CPB) for elective coronary artery bypass grafting. Twenty patients were recruited into each treatment arm and given either PTX 400 mg or placebo three times daily for 1 week before surgery. Patients were well matched. All operations were performed using one anesthetic, CPB, and a myocardial protection technique. Blood and urine samples were taken after anesthetic induction (baseline); 20 min after the start of CPB; 5 min after removal of the cross clamp; and 5 min and 2, 6, and 24 hr after the end of CPB. Pentoxifylline did not reduce IL6, C3a, and LTB4 release but reduced Factor VIIIRAg and urinary albumin excretion preoperatively (PTX vs placebo, ACR 1q.0 vs 2.1 mg/mmol, vWf 0.8 vs 1.3 IU/ml, p < 0.05) and peak levels (PTX vs placebo, ACR 8.9 vs 16.2, vWf 1.2 vs 2.2, p < 0.05) after CPB. These results suggest that PTX may attenuate the endothelial injury and permeability seen in CPB.

Pericardial synovial sarcoma.

Abstract  Synovial sarcomas of the pericardium are very rare. This report describes the case of a 61‐year‐old man presenting with increasing dyspnea on exertion and recurrent pericardial effusions. Echocardiography, computed tomography, and magnetic resonance imaging demonstrated a 6 × 4‐cm pericardial mass lying predominantly over the left atrium. He was treated by surgical excision with the aid of cardiopulmonary bypass, and a subsequent histological analysis confirmed the diagnosis of a pericardial synovial sarcoma.

A saphenous vein graft aneurysm with fistula development to the right atrium: Surgical management of a rare bypass graft complication

A patient presented late following coronary artery bypass surgery with recurrent angina. Investigations revealed a saphenous vein graft aneurysm, which subsequently formed a fistula with the right atrium. This was managed by surgical excision and repair followed by regraft of the run-off territory. Intraoperatively, the left internal mammary artery, a patent graft to the left anterior descending artery, was isolated from the circulation during aortic cross-clamping by preoperative placement of a percutaneous balloon catheter within this graft. Surgery was successful and the patient was discharged symptom-free one week later.

Aortic Root Replacement Using a Biovalsalva Prosthesis in Comparison to a “Handsewn” Composite Bioprosthesis

Abstract  Background: The Biovalsalva aortic root prosthesis incorporates an Elan porcine stentless biological aortic valve suspended within a triple‐layered vascular conduit with preformed aortic sinuses of Valsalva. This study compared implantation of the Biovalsalva prosthesis with a “handsewn” composite bioprosthetic graft (CE Perimount bovine bioprosthesis anastomosed to a gelatin‐impregnated gelweave Dacron graft). Methods: Between December 2004 and January 2009, 39 patients underwent elective or urgent aortic root replacement (modified Bentall procedure with coronary button reimplantation) using a Biovalsalva (n = 21) or a handsewn bioprosthesis (n = 18) for aortic root dilatation. Results: There was no significant difference in the preoperative variables between the two study groups including age (70.7 ± 1.7 vs. 67.6 ± 2.9 years, p > 0.05). There was no in‐hospital mortality. Three patients in each group underwent concomitant aortic hemi‐arch replacement. Patients who underwent Biovalsalva implantation had a reduced need for transfusion of blood (1.25 ± 0.32 vs. 3.17 ± 0.71 units, p < 0.05) and fresh frozen plasma (2.78 ± 0.39 vs. 1.85 ± 0.31, p < 0.05), and reduced mediastinal blood loss (416 ± 52 vs. 583 ± 74 mL, p < 0.05) compared to those with a handsewn bioprosthesis. Cardiopulmonary bypass time (141 ± 6 vs. 170 ± 17 minutes, p = NS) and aortic cross‐clamp time (113 ± 6 vs. 115 ± 7 minutes, p = NS) were similar. Postoperative echocardiography demonstrated excellent hemodynamic function of the Biovalsalva prosthesis (mean size 25.1 ± 0.4 mm valved conduit) with a peak pressure gradient of 26.2 ± 1.9 mmHg and no or trivial valvular regurgitation. Conclusions: The Biovalsalva prosthesis should be considered for patients requiring a biological aortic root replacement. It offers an “off‐the‐shelf” preassembled composite biological valve conduit with excellent hemostatic and hemodynamic properties. (J Card Surg 2010;25:321‐326)

Ostial left coronary stenosis following aortic root reconstruction with BioGlue.

Haemorrhage is a major concern during repair of acute aortic dissection. In such circumstances, glue is often used for tissue reconstruction and also to fortify vascular anastomoses. In this report, we describe a rare case of ostial left main coronary artery stenosis potentially related to previous use of BioGlue.

Management options for aorto-oesophageal fistula: case histories and review of the literature

Objective: An aorto-oesophageal fistula is a rare clinical entity, leading to life-threatening gastrointestinal bleeding. Thoracic aortic aneurysms are the most common cause of aorto-oesophageal fistulae; further causes involve foreign body ingestion, trauma (in most cases iatrogenic), carcinoma or, very rarely, aortitis tuberculotica. Methods: Due to its rarity, there are no large multicentre studies present to evaluate the efficacy of different therapeutic management options. Since it is associated with significant morbidity and mortality, we give a short summary of various treatment approaches performed in our clinical practice in the past three years. The most straightforward therapeutic option may be an endovascular aortic repair and subtotal oesophageal resection followed by gastro-oesophageal reconstruction, but other alternative treatment possibilities are also present, although with probable higher morbidity. Conclusions: Eliminating the source of bleeding as an emergency, resecting the oesophagus urgently to prevent sepsis and reconstructing the gastrointestinal continuity as an elective case after having the inflammatory processes settled seems to justify the endovascular aortic repair and subtotal oesophageal resection, followed by a gastro-oesophageal reconstruction, as an effective surgical approach.

Intrapericardial paraganglioma directly irrigated by the right coronary artery.

Abstract  We present a case of a nonfunctioning intrapericardial paraganglioma that presented as a typical chest pain in a 51‐year‐old woman. The tumor was initially diagnosed on coronary angiography where it had direct irrigation from the right coronary artery. Further computed tomography and magnetic resonance imaging scans showed significant compression of the superior vena cava by the tumor. This was excised through median sternotomy and extracorporeal circulation. Histopathological examination of the mass was characteristic of a paraganglioma.

Mitral valve replacement in severely calcified mitral valve annulus: a 10-year experience

OBJECTIVES Severe calcification in the mitral valve annulus is a challenging problem during mitral valve surgery. We describe our experience with mitral valve replacement in severely calcified mitral valve without decalcification of the annulus. METHODS Between April 2001 and July 2011, 61 patients underwent mitral valve replacement with severe mitral annulus calcification without decalcification of the annulus. This retrospective study was performed to assess the surgical and the long‐term postoperative outcomes in this group. RESULTS The mean age of the patients was 75.2 ± 9.2 years. Twenty‐four patients (53%) were in New York Heart Association Class III/IV. Twenty‐six patients (58%) had good left ventricular function. Mean logistic EuroSCORE was 8.75. Isolated mitral valve replacement was performed in 12 patients (27%). Coronary artery bypass grafting was done in 13 patients (29%). In‐hospital mortality was 4.9% (3 patients). Postoperative morbidity included re‐exploration for bleeding in 3 patients (7%) and transient renal impairment in 10 patients (22%). Three patients required intra‐aortic balloon pump (7%) for low cardiac output syndrome. Seven patients (16%) required permanent pacemaker, and 1 patient (2%) had thromboembolic event. The 1‐year survival was 93.3%, and the 5‐year survival was 78.8%. The mean echocardiography follow‐up was 40 months. There was no paravalvular leak detected in any patient in the long‐term follow‐up. None of the patients had valve‐related reoperation. CONCLUSIONS Mitral valve replacement without annular decalcification in severely calcified mitral valve annulus is a safe and an effective approach and has good long‐term outcome.

Anomalous aortic origin of the right coronary artery. An unusual cause of angina pectoris and its surgical correction.

A 45-year-old female presented with typical recent-onset exertional angina pectoris. Subsequent investigation showed that the likely cause was an aberrant origin of the right coronary artery arising from the left coronary sinus. This anomaly is uncommon and is not usually associated with angina pectoris. Surgical rerouting of the origin of the right coronary artery produced complete resolution of ischaemia.