Primary cardiac lymphoma causing right atrial occlusion.

Primary cardiac lymphomas (PCL) are extremely rare, and diffuse large B-cell lymphoma is a highly aggressive subtype. We report a case that was initially diagnosed as chronic right heart dysfunction. Detailed investigations revealed a large lobulated tumour occluding the right atrium, infiltrating the inter-atrial septum, the roof of the left atrium, and the aortic root. Despite adequate surgical debulking and initial successful tricuspid annuloplasty, the patient succumbed to multi-organ failure. Pathological analysis of the resected tumour confirmed a diffuse large B-cell lymphoma with a proliferation rate of 100%. What is unique about this case is the size of this rare cardiac tumour, which we believe to be one of the largest described in the literature for a purely intra-cardiac PCL, its aggressive growth rate, and the relatively mild symptomatology until a late stage of the disease.

Respiratory distress after surgery of RVOT pathologies: a word of caution on pseudoaneurysm development.

Pseudoaneurysm of the right ventricle outflow tract (RVOT) is a rare complication in pediatric cardiac surgery. We report a patient who developed a right ventricular pseudoaneurysm 8 months after RVOT enlargement using a pericardial patch for infundibular pulmonary stenosis. Our patient was born with severe pulmonary valvular stenosis and treated with percutaneous balloon valvotomy in the neonatal period. Six months later, she developed infundibular pulmonary stenosis, which required surgical resection of right ventricle infundibular trabeculations and bovine pericardial patch enlargement. The postoperative period was normal. She was readmitted to hospital 5 months later complaining of wheezing, coughing and shortness of breath. Echocardiography showed a huge aneurysmal dilatation of the outflow patch in connection with the right ventricular cavity. The patient underwent resection of the pseudoaneurysm and former patch, followed by interposition of a bovine jugular vein conduit between the RVOT and pulmonary bifurcation. The early postoperative period was uncomplicated. On echocardiography, no significant residual gradient was measured through the conduit and there was no insufficiency of the valve. RVOT reconstruction with patch enlargement, homograft or conduit implantation can be the origin of pseudoaneurysms. Although their incidence is rare, they are often asymptomatic before becoming quite large and causing compression symptoms as in our patient with respiratory complaints due to airway compression. It is important to follow up these patients closely, especially in the first year after surgery since most aneurysms develop within 6 months of surgery.

Vascular ultrasound studies for the non-invasive assessment of vascular flow and patency in experimental surgery in the pig.

Vascular ultrasound is a reliable non-invasive tool used for the routine assessment of vascular flow and patency in human recipients. We describe the use at three different time points (immediately, 1 week and 4 weeks postsurgery) of ultrasound studies and its validation by angiographic studies in 37 swine undergoing carotid graft replacement. We calculated predictive values (>92%), sensitivity (>85%) and specificity (>92%) with high results at all time points. Ultrasound appeared as an accessible non-invasive technique, providing rapid, safe, repeatable and reliable results. It is an excellent alternative to angiography, avoiding risks inherent to invasive methods and therefore contributing to animal welfare.

Use of extracorporeal circulation and selective renal perfusion during the surgical correction of abdominal aortic coarctation.

Coarctation of the abdominal aorta is a rare pathology. Stenosis of visceral and renal arteries may present together with coarctation, which requires specific operation techniques. We present the case of a patient with coarctation of the abdominal aorta associated with stenosis of the celiac trunk, the superior mesenteric and the right renal arteries. Distal aortic perfusion by extracorporeal circulation and selective right renal perfusion techniques were used during the operation to protect the spinal cord and kidney against hypoperfusion and ischemia.

Mitral tendon prolapsing into the left ventricular outflow tract.

Intracardiac masses of the mitral valve are rare. Their differential diagnosis is wide, ranging from tumors (myxomas, lipomas and fibroelastomas), thrombi and abnormal muscular or fibrous bands. We report a case and management. A 68 year-old asymptomatic female who had undergone coronary angioplasty and stent placement in the left anterior descending artery for acute myocardial infarction four years earlier, was shown to have, on routine follow-up, an intracardiac mass originating from the anterior leaflet of the mitral valve and prolapsing into the left ventricular outflow tract (LVOT). The patient underwent surgical excision of the mass under cardiopulmonary bypass, to prevent cerebral or coronary embolization and sudden death due to the highly sensitive location of the mass, in the high-velocity flow LVOT. A transverse aortotomy provided exposure of the ventricular surface of the anterior mitral leaflet and revealed a fusiform mass attached to the medial segment of the anterior leaflet, resembling a secondary cordae, measuring 20 by 3 mm. The implantation was calcified on the ventricular aspect of the anterior mitral leaflet. This mass was completely excised. Postoperative recovery was uneventful. Peroperative and postoperative transesophageal echocardiography were normal. Histological examination showed a partially necrosed and calcified fibrous tissue lined by endothelium. The final diagnosis was that of a mitral tendon. Intracardiac masses of the mitral valve are rare lesions, mostly papillary fibroelastomas and myxomas and more rarely mitral tendons, which require surgical resection for prevention of embolization. The definitive diagnosis is often only obtained on histological analysis.

PPS-PEG surface coating to reduce thrombogenicity of small diameter ePTFE vascular grafts.

AIMS: Patency failure of small vascular synthetic grafts is still a major problem for coronary and peripheral revascularization. Thus, three new surface coatings of small synthetic grafts were tested in an acute pig model to evaluate their thrombogenicity (extracorporeal arterio-venous shunt) and in a chronic rat model to evaluate the tissue reaction they induced (subcutaneous implantation). METHODS: In five domestic pigs (25-30 kg) an extracorporeal femoro-femoral arterio-venous shunt model was used. The study protocol included first a non-heparinized perfusion sequence followed by graft perfusion after 10,000 UI iv heparin. Grafts were perfused for 3 and 9 minutes. The following coatings were tested on ePTFE grafts: poly-propylene sulphide (PPS)--poly-ethylene glycol (PEG) (wet and dry applications) as well as carbon. Two sets of control were used, one dry and one wet (vehicle only). After perfusion grafts were examined by scanning electron microscopy for semi-quantitative assessment (score 0-3) of cellular and microthrombi deposition. To assess tissue compatibility, pieces of each material were implanted subcutaneously in 16 Wistar rats. At 2, 4, 8, 12 weeks four animals each were sacrificed for semi-quantitative (score 0-3) histologic evaluation of tissue reaction. RESULTS: In the pig model, cellular deposition and microthrombi formation increased over time. In non- heparinized animals, the coatings did not improve the surface characteristics, since they did not prevent microthrombi formation and cellular deposition. In heparinized animals, thrombogenicity was lowest in coated grafts,especially in PPS -PEG dry (p<0.05), and highest in controls. Cell deposition was lowest in PPS-PEG dry, but this difference was not statistically significant vs.controls. In the rat model,no significant differences of the tissue reaction could be shown between materials. CONCLUSION: While all coatings failed to add any benefit for lowering tissue reaction, surface coating with PPS -PEG (dry application) reduced thrombogenicity significantly (in heparinized animals) and thus appears to be promising for improving graft patency of small synthetic vascular prostheses.

The importance of aprotinin and pentoxifylline in preventing leukocyte sequestration and lung injury caused by protamine at the end of cardiopulmonary bypass surgery.

BACKGROUND: Protamine has adverse effects on pulmonary gas exchange during the postoperative period. The objective of this study was to investigate the importance of aprotinin and pentoxifylline in preventing the leukocyte sequestration and lung injury caused by protamine administered after the termination of cardiopulmonary bypass (CPB). METHODS: Participants (n = 39) were allocated into three groups at the termination of CPB: Group 1, (control group, n = 16); Group 2 (aprotinin group, n = 12), who received protamine + aprotinin (15,000 IU/kg); and Group 3 (Pentoxifylline group, n = 11), who received protamine + pentoxifylline (10 mg/kg). Leukocyte counts in pulmonary and radial arteries were determined after the termination of CPB and before any drug was given (t1), and 5 minutes (t2), 2 hours (t3), 6 hours (t4) and 12 hours (t5) after the administration of protamine. Alveolar-arterial O2 gradient (A-aO2) and dynamic pulmonary compliance were measured at t1, t2 and t3. RESULTS: In the control group, an increase in pulmonary leukocyte sequestration was observed 5 minutes and 2 hours after protamine administration, after which this difference disappeared. No significant degree of pulmonary sequestration was detected in any measurements after protamine was administered in the aprotinin and pentoxifylline (PTX) groups. Dynamic lung compliance was 50.1, 45.2 and 47.2 ml/cm H2O in the control group, 49.2, 61.1 and 56.3 ml/cm H2O in the aprotinin group, and 49.5, 54.5 and 50.4 ml/cm H2O in the PTX group. The A-aO2 gradient was 212.2, 263.3 and 254.3 mm Hg in the control group, 209.4, 257.1 and 217.3 mm Hg in the aprotinin group, and 211.3, 260.8 and 219.2 mm Hg in the PTX group. CONCLUSION: Aprotinin and PTX treatments have favourable effects on lung function by reducing protamine-induced leukocyte sequestration into lungs at the end of CPB.

The histological effect of harmonic scalpel and electrocautery in lung resections. An experimental study in a rat model.

AIM: In the last decade, ultrasonically activated scalpels (the Harmonic Scalpel, HS) have been developed and used for both open and endoscopic surgical procedures. The present study compares the deepness of lung tissue damage caused by HS and unipolar electrocautery (EC) in rats. METHODS: Ten rats were used for the study. Morphological damage on lung parenchyma of the rats was measured with the ocular micrometer in light microscopy. RESULTS: The mean depth of the tissue damage was 0.23+/-0.08 mm in the HS group, and 0.33+/-0.10 mm in the EC group. The difference was statistically significant between the 2 groups (p=0.028). CONCLUSION: HS induces significantly less tissue damage than EC in rat lungs.

The effects of intracoronary administration of vitamin E on myocardial ischemia-reperfusion injury during coronary artery surgery.

BACKGROUND: Vitamin E has a strong antioxidant capacity, and has been used in several ischemia-reperfusion studies. The aim of this study was to investigate the effects of water-soluble vitamin E (alpha-tocopherol) on myocardial protection during coronary artery surgery. METHODS: Water soluble vitamin E (100 mg) in tepid saline (n = 14) or tepid saline alone (n = 16) was administered into the coronary arteries at the end of aortic cross-clamping. Cardiac troponin-I (cTn-I), MB-isoenzyme of creatine kinase (CK-MB), myoglobin, blood gas, and lactate levels in systemic and coronary sinus blood and hemodynamic variables were assessed during and after the operation. RESULTS: Eight hours after reperfusion, cTn-I levels increased to 3.06 +/- 1.8 ng/ml and 6.97 +/- 3.9 ng/ml in the vitamin E group and control group, respectively (p = 0.01). Coronary sinus lactate concentration was 2.68 +/- 0.5 mmol/l in the vitamin E group and 4.01 +/- 1.5 mmol/l in the control group 60 minutes after reperfusion (p = 0.027). CONCLUSIONS: Administration of vitamin E into the coronary arteries before removal of the aortic cross-clamp can reduce myocardial cell injury and protect the myocardium from ischemia-reperfusion injury.

The importance of pulmonary artery circulation during cardiopulmonary bypass.

This study sought to determine changes in transpulmonary difference in blood cells and alveolar-arterial oxygen (A-aO2) gradient when pulmonary artery circulation was obstructed in patients undergoing coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB). Eighteen patients were divided into group A (control group; X-clamp placed on aorta, n = 9) and group B (pulmonary ischaemia group; X-clamp placed on aorta and pulmonary artery, n = 9). Haematological parameters were compared before CPB and up to 90 min after declamping. A-aO2 gradient differences were compared before and 2 h and 6 h after declamping. A transpulmonary increase in leucocyte levels normalized after 60 min in group A but remained higher in group B. A transpulmonary increase in neutrophils normalized after 60 min in group A and 90 min in group B. Increased lymphocyte levels normalized after 30 min in group A and 90 min in group B. A-aO2 gradient was determined as: group A (294.8 +/- 74.3) and group B (321.2 +/- 73.3) before X-clamping; group A (132.7 +/- 22.7) and group B (236.6 +/- 41.5) 2 h after declamping; and group A (72.2 +/- 22.7) and group B (189.4 +/- 88.9) 6 h after declamping. When pulmonary artery circulation was obstructed during the X-clamping period, leucocyte, neutrophil and lymphocyte sequestration within both lungs increased, and an increased A-aO2 gradient was observed because of tissue damage. To prevent post-operative complications, precautions to maintain normal pulmonary artery circulation are recommended.

The effects of cardiopulmonary bypass on androgen hormones in coronary artery bypass surgery.

The effects of testosterone on coronary vasomotor regulation have been described by several recent reports. Here we investigated changes in serum androgen levels during and after cardiopulmonary bypass (CPB) in patients who had undergone coronary artery bypass surgery. Serum luteinizing hormone, free testosterone and dihydroepiandrestenedione sulphate (DHEA sulphate) levels were evaluated in 38 male coronary artery bypass surgery patients using a chemical immunoassay technique. All hormone levels were corrected to account for haemodilution. Serum-free testosterone level decreased significantly during weaning from CPB (from 15.7 +/- 4.2 nmol/l to 6.2 +/- 2.8 nmol/l), and an even greater decrease was observed in the first post-operative day (5.4 +/- 3.1 nmol/l). On the seventh post-operative day, free testosterone levels reached a normal value (11.8 +/- 5.5 nmol/l), although they were still significantly lower compared with the pre-operative value. There were slight alterations in serum DHEA sulphate levels, although the only significant decrease occurred from the first to the seventh day post-operation (from 4.7 +/- 2.2 mumol/l to 3.7 +/- 1.8 mumol/l, respectively). Serum luteinizing hormone levels were decreased during weaning from CPB (from 4.8 +/- 2.1 mIU/ml to 3.9 +/- 1.8 mIU/ml), but increased rapidly to the pre-operative value (5.5 +/- 2.5 mIU/ml) at the first post-operative day. These results show that CPB affects serum luteinizing hormone, free testosterone and dihydroepiandrestenedione sulphate levels. The free testosterone level decreases significantly both during and after CPB surgery.

The effects of modified hemofiltration on inflammatory mediators and cardiac performance in coronary artery bypass grafting.

Cardiopulmonary bypass increases the blood levels of various immune mediators, thereby leading to a systemic inflammatory response syndrome, e.g. sepsis, with some hemodynamic alterations, such as vasodilatation, tachycardia, and a decrease in systemic vascular resistance. Perioperative hemofiltration is one of the treatment modalities proposed to prevent this syndrome. Modified hemofiltration has been introduced recently by investigators who recommend that the former standard techniques are ineffective in eliminating the inflammatory mediators. The purpose of this study was to determine the effects of the modified technique on these mediators and on hemodynamic parameters. Forty patients undergoing coronary artery bypass grafting were randomized into equal control and hemofiltered groups. The hemodynamic parameters, as well as blood samples, were taken before and after hemofiltration to assess blood concentrations of interleukin-6, interleukin-8 and neopterin. The hemodynamic parameters and immune mediator levels did not differ between the two groups during the course of the study, except in the immediate postoperative periods, where cardiac output, cardiac index, and systemic vascular resistance values were significantly greater in the hemofiltered group while there were no differences in the immune mediators. The results of our study suggest that the effects of modified hemofiltration on immune mediators are still debatable. The improvement found in cardiac performance could be attributed to the prevention of hemodilution and hypervolemia.

Determinants of early mortality and neurological morbidity in aortic operations performed under circulatory arrest.

OBJECTIVE: Aneurysms and dissections of the thoracic aorta continue to present a surgical challenge and their incidence is increasing in recent years. The mortality rate of surgical treatment is still higher than those of other cardiovascular operations. Neurological injury is the most feared complication resulting from repair of these lesions. This study aims to determine the factors that influence the neurological outcome and mortality after thoracic aortic operations. METHODS: During the period from November 1993 through May 1999, 144 patients were operated on for conditions involving the ascending aorta and/or aortic arch. Ninety-five (66.0%) were operated for aortic dissection and 49 (34.0%) were for aortic aneurysms. Sixty-two patients (43.1%) had replacement of ascending aorta with distal open technique; 82 patients (56.9%) had hemiarch or total arch replacement or repair of the distal arch. RESULTS: Twenty-seven (18.7%) early deaths occurred. New stroke occurred in two patients (1.4%) and temporary neurological dysfunction in nine patients (6.3%). Deep hypothermic circulatory arrest with retrograde cerebral perfusion was used in all patients. On multivariate logistic regression analysis, risk factors for mortality were chronic renal failure, preoperative organ malperfusion, rupture, total circulatory arrest time > 60 minutes, postoperative acute renal failure, postoperative low cardiac output, sepsis, and multiple organ failure. Risk factors for neurological morbidity were preoperative chronic renal failure, preoperative hemodynamic instability, postoperative low cardiac output, and pulmonary complications. CONCLUSIONS: Hypothermic circulatory arrest with retrograde cerebral perfusion was not an independent predictor of neurological morbidity on multivariate analysis, even if the arrest period was more than 60 minutes. Lengths of circulatory arrest periods and clinical presentations of the patients are important determinants of mortality.

Intramural hydatid cyst of descending aorta complicated by false aneurysm.

Hydatid disease is caused by the larval stage of Echinococcus granulosus, and the resultant fluid-filled cysts almost invariably affect the liver. Primary involvement of the aortic wall is very rare. We report a case of hydatid disease presenting as a huge cyst invading the wall of the descending aorta and complicated by a false aneurysm. Diagnostic problems and operative management are reviewed.

Proximal clamping levels in abdominal aortic aneurysm surgery.

In the surgical treatment of abdominal aortic aneurysm, the single proximal cross-clamp can be placed at 3 alternative aortic levels: infrarenal, hiatal, and thoracic. We performed this retrospective study to evaluate the advantages and disadvantages of the 3 main aortic clamping locations. Eighty patients presented at our institution with abdominal aortic aneurysms from March 1993 through May 1998. Fifty of these patients had intact aneurysms and underwent elective surgery, and 30 had ruptured aneurysms that necessitated emergency surgery. Proximal aortic clamping was applied at the infrarenal level in 24 patients (22 from the intact aneurysm group, 2 from the ruptured group), at the hiatal level in 34 patients (22 intact, 12 ruptured), and at the thoracic level (descending aorta) via a limited left lateral thoracotomy in 22 patients (6 intact, 16 ruptured). Early mortality rates (within 30 days) were 4% (2 of 50 patients) among patients with intact aneurysms and 40% (12 of 30 patients) among those with ruptured aneurysms. In the 2 patients from the intact aneurysm group, proximal aortic clamps were applied at the hiatal level. In the ruptured aneurysm group, proximal aortic clamps were placed at the thoracic level in 10 patients, the infrarenal level in 1, and the hiatal level in 1. According to our study, the clinical status of the patient and the degree of operative urgency--as determined by the extent of the aneurysm--generally dictate the proximal clamp location. Patients who present with aneurysmal rupture or hypovolemic shock benefit from thoracic clamping, because it restores the blood pressure and allows time to replace the volume deficit. Infrarenal placement is advantageous in patients with intact aneurysms if there is sufficient space for the clamp between the renal arteries and the aortic aneurysm. In patients with juxtarenal aneurysms, hiatal clamping enables safe and easy anastomosis to the healthy aorta. Clamping at this level also helps prevent late anastomotic aneurysm formation, which is frequently encountered after inadvertent anastomosis of the graft to a diseased portion of the aorta. Further studies are needed in order to confirm these results.