Antegrade thoracic endovascular aneurysm repair via the ascending aorta

PURPOSE

We performed antegrade thoracic endovascular aneurysm repair via the ascending aorta in selected high-risk patients scheduled for open surgery, in whom an iliofemoral or abdominal aortic approach was not feasible. We present our initial experience with this approach.

METHODS

Of 16 consecutive patients who underwent antegrade endovascular aneurysm repair via the ascending aorta at our institution, 3 had an emergency intervention for rupture and 3 had an urgent intervention for impending rupture or complicated aortic dissection. The procedure was scheduled in 10 patients. The median patient age was 77 years. In 13 patients, one or more concomitant procedures were performed. In 6 patients, vascular access for endovascular aneurysm repair was obtained via a branch of the replacement graft. In 10 patients, direct cannulation of the ascending aorta was carried out using 2 pursestring sutures.

RESULTS

The initial success rate was 100%. Early mortality occurred in 2 (12.5%) patients because of multiple organ failure in one and heart failure in the other. No patient required a second intervention during follow-up. The mean duration of follow-up was 19 months.

CONCLUSION

The antegrade approach is a useful alternative in patients with no access suitable for endovascular aneurysm repair and who are not appropriate candidates for open conventional thoracic aortic surgery. This approach is applicable to selected patients.

Clinical efficacy of thrombus aspiration on 5-year clinical outcomes in patients with ST-segment elevation acute myocardial infarction undergoing percutaneous coronary intervention

Background

Adjunctive thrombus aspiration (TA) during primary percutaneous coronary intervention (PCI) was reported to promote better coronary and myocardial reperfusion. However, long-term mortality benefit of TA remains controversial. The objective of this study is to investigate the clinical impact of TA on long-term clinical outcomes in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary PCI.

Methods and Results

The CREDO-Kyoto AMI Registry is a large-scale cohort study of acute myocardial infarction patients undergoing coronary revascularization in 2005–2007 at 26 hospitals in Japan. Among 5429 patients enrolled in the registry, the current study population consisted of 3536 patients who arrived at the hospital within 12 hours after the symptom onset and underwent primary PCI. Clinical outcomes were compared between the 2 patient groups with or without TA. During primary PCI procedures, 2239 out of 3536 (63%) patients underwent TA (TA group). The cumulative 5-year incidence of all-cause death was significantly lower in the TA group than in the non-TA group (18.5% versus 23.9%, log-rank P<0.001). After adjusting for confounders, however, the risk for all-cause death in the TA group was not significantly lower than that in the non-TA group (hazard ratio: 0.90, 95% CI: 0.76 to 1.06, P=0.21). The adjusted risks for cardiac death, myocardial infarction, stroke, and target-lesion revascularization were also not significantly different between the 2 groups.

Conclusions

Adjunctive TA during primary PCI was not associated with better 5-year mortality in STEMI patients.

Ruptured saphenous vein graft aneurysm after aortocoronary bypass grafting

Computed tomography demonstrated a giant saphenous vein graft aneurysm that compressed the right atrium of a 72-year-old woman 20 years after undergoing coronary artery bypass grafting. Angiography revealed contrast medium leakage in the mid-portion of the graft aneurysm. Aneurysmectomy was performed without repeat grafting. Postoperative myocardial scintigraphy demonstrated no significant myocardial ischemia. The ischemic effect of non-revascularization should be considered preoperatively because of the difficulties with repeat grafting.

Amorphism and Physicochemical Stability of Spray-dried Frusemide

The physicochemical properties of amorphous forms of frusemide, prepared by spray-drying at 50 or 150°C, and their hygroscopic stability at temperatures of 25 and 40°C, and at 0 and 75% relative humidity were investigated. The glass transition temperature of the amorphous form A was 44·2°C as measured by differential scanning calorimetry, while that of the amorphous form B was 54·4°C. The activation energies for glass transition and crystallization processes were calculated from the differential scanning calorimetry thermograms of amorphous forms A and B, respectively. Stability determined by X-ray diffraction at 0% relative humidity, 25 and 40°C suggested that form B was more stable than form A. However, the stability of form A at 75% relative humidity and 25 and 40°C was similar to that of form B.

[Infective endocarditis complicated with ruptured mycotic intracranial aneurysms]

A 38-year-old man was hospitalized complaining of an episode of syncope. He was diagnosed with acute infective endocarditis (IE) of the aortic and the mitral valves with mobile and large vegetations, complicated with mycotic cerebral emboli related to the left anterior and the middle cerebral arteries. Double valve replacement with mechanical prosthesis was performed within 24 hours after cerebral accident occurred. On the 36 postoperative day, emergency cerebrovascular surgery was done due to rupture of a mycotic intracranial aneurysm. He was discharged on foot without any neurological abnormal finding. The optimum treatment of IE complicated with cerebral embolism is a controversial theme. Management should be considered carefully in individual cases.

Antegrade selective cerebral perfusion with mild hypothermic systemic circulatory arrest during thoracic aortic surgery

OBJECTIVE

Antegrade selective cerebral perfusion (ASCP) and retrograde cerebral perfusion (RCP) have proven to be reliable methods of brain protection during aortic surgery. These techniques are usually accompanied by systemic circulatory arrest with moderate hypothermia (24-28 degrees C) or deep hypothermia (18-24 degrees C). However, hypothermia can lead to various problems. The present study therefore reports results for thoracic aorta replacement using ASCP with mild hypothermic systemic arrest (28-32 degrees C).

DESIGN

Between 1995 and 2003, 68 consecutive patients underwent repair of the ascending aorta and/or aortic arch. Mild hypothermic ASCP was utilized in 31 cases, moderate hypothermic ASCP in 20, and deep hypothermic RCP in 17. Various parameters were compared between the mild hypothermic ASCP, moderate hypothermic ASCP, and RCP.

RESULTS

Hospital mortality was 10.3%, with no significant differences observed between any groups. Permanent neurological dysfunction was 8.8%, and no significant differences were observed between any groups. Mild hypothermic ASCP displayed significantly decreased transfusion volume, intubation time, and ICU stay.

CONCLUSIONS

Use of ASCP with mild hypothermic systemic circulatory arrest during aortic surgery resulted in acceptable hospital mortality and neurological outcomes. ASCP with mild hypothermic arrest allows decreased transfusion volume and reduced duration of intubation and ICU stay.

Cardiac Tamponade due to a Ruptured Solitary Mediastinal Varix: A Case Report

Mediastinal varix is rare. Some reports have noted that the mediastinal vein can become varicose in cases of portal hypertension or obstruction of the vena cava. However, solitary mediastinal varices without portal hypertension or obstruction of the vena cava are very rare. Mediastinal varicose veins have been problematic as pseudotumors, as no symptoms have been described in the literature. We encountered a case of cardiac tamponade due to a ruptured solitary mediastinal varicose vein. To the best of our knowledge, this is the first report of sustained symptomatic mediastinal varicose vein.

Patent Levoatrial Cardinal Vein Without Left Heart Hypoplasia

We report a very rare case of a 38-year-old woman with an anomalous vein connecting the left atrium and superior vena cava. This vein originated from the roof of the left atrium and crossed the midline to join the normal right superior vena cava. Furthermore, there was no hypoplasia of the left heart, the atrial septum was intact, and all four pulmonary veins drained normally into the left atrium. Three-dimensional reconstructions and sagittal views on preoperative computed tomography clearly demonstrated a communication between the superior vena cava and the left atrium. The patient experienced increasing left-to-right shunt ratio and underwent successful surgical correction 3 years after the original diagnosis via ligation of the anomalous vein. This abnormal vein was considered to be a levoatrial cardinal vein. The embryology, physiology, diagnosis, and surgical repair of this rare lesion are discussed.

Delayed Esophageal Necrosis and Perforation Secondary to Thoracic Aortic Rupture: A Case Report and Review of the Literature

Delayed esophageal necrosis secondary to aortic rupture is extremely rare but potentially fatal. Although diagnostic techniques have improved, survival remains rare. The clinical and imaging features have not been characterized, as no large series have been reported since the advent of computed tomography (CT) and endoscopy. Moreover, as delayed esophageal necrosis secondary to aortic rupture is rarely anticipated, diagnosis is usually delayed. We recently encountered a case of this complication and present this along with a literature review, in order to facilitate early recognition and treatment. In many cases, hemodynamics remain relatively stable despite aortic rupture and the long interval between onset and operation. Dysphagia is therefore an important symptom that may indicate compression of the esophagus and subsequent esophageal necrosis. Preoperative total obstruction of the esophagus on barium swallow, endoscopy, or CT is also an important feature suggesting ischemic change of the esophagus. Endoscopy often reveals an annular ulcer suggestive of an ischemic process leading to necrosis. Death generally occurs from severe mediastinitis occurring after graft repair of the aorta. We recommend performing postoperative endoscopy after aortic surgery when preoperative obstruction of esophagus is found. If endoscopy reveals annular necrosis, surgical treatment involving esophagectomy and omental translocation should be performed expediently before perforation occurs.

Obstructed Coarctation in a Right Aortic Arch in an Adult Female

Coarctation of a right aortic arch is rare congenital anomaly. We report a rare case of a 24-year-old female with coarctation of the right aortic arch with aberrant left subclavian artery between the right common carotid and right subclavian arteries. The coarctation progressed into complete obstruction as the interruption of the aorta in adulthood. To prevent cerebral complications and progression to heart failure, surgical procedure was selected. Extraanatomical bypass grafting between the ascending and descending aorta was successfully performed using cardiopulmonary bypass. Some patients diagnosed with interruption of the aortic arch in adulthood might be displaying progression of undiagnosed coarctation, as our in case. Three-dimensional computed tomography was useful to detect the obstructive lesion and to determine the surgical approach and methods.

Intravascular extraction of permanent pacemaker leads

PURPOSE

Cardiac leads that became infected, fail, or are otherwise problematic present difficulties in the management of patients. In this report, we assess our intravascular countertraction technique.

METHOD

Between February 1990 and January 2001, 13 leads were removed from 11 patients using the intravascular countertraction technique. The reasons for lead extraction were pacemaker infection and lead dysfunction.

RESULTS

In two of these patients, the ventricular leads could not be completely removed. The complete success rate was 85% and the overall success rate was 92%. There were no serious complications such as cardiac rupture, vein injury, or death, and there were no clinical signs of pulmonary embolism. In one of the patients whose ventricular leads could not be removed completely, the ventricular lead was stretched from its previous round shape, but tricuspid valve regurgitation did not occur during the 3-year follow-up period. In the other patient, the distal electrode was left in the subclavian vein. However, this residual distal electrode did not migrate, and there were no clinical signs of any recurrence of infection.

CONCLUSIONS

The present study suggests that to remove leads successfully, the largest locking stylet that can be easily passed to the lead's tip through the coil lumen should be chosen in order to avoid valve injury, which can sometimes occur when a ventricular lead's locking stylet is left in the coil lumen.

[Pitfall of modified ultrafiltration in pediatric cardiac surgery]

Since June, 1998, modified ultrafiltration (MUF) was performed for 92 consecutive children who underwent cardiac surgery using cardiopulmonary bypass, except those with atrial septal defect. Among 92 cases, MUF could not be completed in two cases because of the accident that many air bubbles were found in the arterial line of the CPB circuit. The causes of such trouble were discussed.

Modified ultrafiltration may improve postoperative pulmonary function in children with a ventricular septal defect

To evaluate the effectiveness of modified ultrafiltration (MUF) on ventricular septal defect (VSD) repair in children, we retrospectively examined 10 patients who underwent VSD repair with MUF at the Kinki University School of Medicine hospital between June 1998, and December 1998 (MUF group). These patients were compared with 14 patients who underwent the same procedure without MUF (control group) between January 1997 and June 1998. Systolic blood pressure and hematocrit values increased significantly during MUF. By the time of postoperative transfer to the intensive care unit, PaO2 was higher in the MUF group than in the control group (503.3 +/- 112.2mmHg vs 376.3 +/- 149.2mmHg; P = 0.0491), whereas A-aDO2 was lower in the MUF group than in the control group (171.9 +/- 109.2mmHg vs 301.1 x 150.4mmHg; P = 0.0449). These findings demonstrate that MUF had a beneficial effect on pulmonary function in children who underwent surgery to repair a VSD.

Total cavopulmonary connection using a pedicled pericardial conduit for a patient with apicocaval juxtaposition

A 5-year-old boy, with a double inlet solitary ventricle, pulmonary atresia, and apicocaval juxtaposition underwent an extracardiac total cavopulmonary connection. A pedicled pericardial conduit was placed behind the ventricle to make a straight pathway between the inferior vena cava and pulmonary artery. This report presents a solution for managing patients with complicated heart defects with apicocaval juxtaposition during the completion of a total cavopulmonary connection.

Disseminated cholesterol embolism after coronary artery bypass grafting

Blue toe syndrome caused by cholesterol emboli is a relatively benign disease. However, disseminated cholesterol embolism is a life-threatening condition. We describe here the case of a 71-year-old female admitted because of anterior chest pain and intermittent claudication. Following cardiac catheterization, warfarin potassium was administered. However, the patient's toes soon darkened bilaterally, and BUN and creatinine levels increased from the normal value. Skin discoloration and renal failure were improved after stopping warfarin potassium administration. The patient underwent coronary artery bypass grafting and left femoropopliteal bypass. Cerebral infarction and renal failure occurred postoperatively due to disseminated cholesterol embolism. The patient died from renal failure on the 16th postoperative day without regaining consciousness following surgery. For high risk patients, interventional procedures to the ascending aorta must be avoided. When CABG cannot be avoided for coronary revascularization, off-pump bypass and use of arterial grafts are recommended.

Treatment of deep infection following thoracic aorta graft replacement without graft removal

Deep infection following thoracic aortic replacement constitutes an extremely serious and life-threatening complication, and its treatment remains a challenge to surgeons. We report our experience involving five patients in whom deep infection occurred around the graft. Four of the five patients were treated by emergency surgery and one was treated by elective surgery. Surgical procedures performed including hemiarch replacement in one case, total arch replacement in one case, suspension of aortic valve and ascending aorta replacement in one case, Bentall procedure in one case, and descending aorta re-replacement in one case. Methicillin-resistant Staphylococcus aureus was detected in four patients, methicillin-resistant Staphylococcus epidermidis in one, and Aspergillus in one patient from purulent discharge at the operative site. Reoperative debridement and irrigation drainage were carried out at an early phase of infection. Intermittent irrigation following the reoperation was performed in all cases. In addition, muscle flap filling or omental translocation was carried out in three patients. Although the reported principle of treatment for arterial graft infection is extraanatomical bypass or rereplacement after removal of the infected graft, such procedures may be technically difficult and have a high risk at the thoracic level. Local anti-septic irrigation, administration of antibiotics, and vascular-rich tissue filling are useful procedures, and it appears that it is not always necessary to remove prosthetic grafts.

Postischemic reperfusion injury can be attenuated by oxygen tension control

Oxygen-derived free radicals cause cytotoxic damage during reperfusion after a period of ischemia and the production of these free radicals may be proportionate to oxygen tension (PO2). The present study tested the hypothesis that oxidative damage may be limited by maintaining a more physiologic PO2 following ischemia. An experimental study in Wistar rats were mounted on a Langendorff apparatus was conducted to estimate baseline aortic flow (AF), coronary flow (CF), cardiac output (CO), systolic pressure (SP), heart rate (HR), and the rate-pressure product (RPP: HRxSP). The hearts were divided into 3 groups (n=7, hearts/group): group 1, hypoxic (PO2=300+/-50 mmHg) reperfusion; group 2, middleoxic (PO2=500+/-50 mmHg) reperfusion; and group 3, hyperoxic (PO2=700+/-50 mmHg) reperfusion. Following 30 min of warm ischemia, hearts in all groups were reperfused at each oxygen pressure. The recovery of cardiac function of each heart was measured at the end of reperfusion. Concentrations of lactate (LAC), lactate dehydrogenase (LDH), and creatine kinase (CK) in the coronary perfusate during reperfusion were measured. The recovery rate of CO, SP, and RPP in group 2 were all significantly better than in the other 2 groups. CK leakage in group 2 was significantly lower than in group 3. A clinical study was also conducted during elective coronary artery bypass grafts in 16 consecutive patients who underwent either hyperoxic (n=8, PO2=450-550 mmHg) or more physiologic (n=8, PO2=200-250 mmHg) cardiopulmonary bypass after aortic unclamping. The clinical study assessed CK-MB, LDH, LAC, and malondialdehyde (MDA) in patient blood prior to starting the surgical procedure and at 30 min and 3, 9, and 21 h after unclamping. Cardiac index (CI), central venous pressure, pulmonary capillary wedge pressure, systolic arterial pressure, and the dose of cathecholamines were also measured. Although no significant differences were present in the dose of cathecholamines, the CI in the more physiologic oxygen tension group was significantly higher than in the hyperoxic group at 3 and 6 h after unclamping. The levels of MDA in the more physiologic PO2 group was significantly lower at 30 min after aortic unclamping than in the hyperoxic group. The present results suggest that in the experimental as well as in the clinical study, high PO2 leads to myocardial reperfusion damage; however, maintaining a more physiologic PO2 during reperfusion following ischemia may attenuate reperfusion injury.

A case of Standford type B aortic dissection involving a right-sided aortic arch with mirror-image branching and right-sided descending aorta

Isolated right aortic arch with mirror-image branching is a rare congenital anomaly. To date, no case has been reported for aortic dissection involving a right aortic arch with mirror-image branching. We report here on a case involving a 58-year-old man in whom expanding type B aortic dissection was demonstrated in the right aortic arch with mirror-image branching and a right descending aorta. The patient was successfully treated by interposition of a prosthetic graft via a right posterolateral thoracotomy approach. We also reviewed the literature.

Cardiac operation for a patient with autoimmune hemolytic anemia with warm-reactive antibodies

We present a case of a patient with autoimmune hemolytic anemia with warm-reactive antibodies who underwent successful coronary artery bypass grafting. We discuss some of the important problematic issues related to perioperative management.

Modified ultrafiltration removes serum interleukin-8 in adult cardiac surgery

Cardiopulmonary bypass (CPB) causes an increase in serum cytokine levels and systemic inflamatory responses, which may trigger the onset of various types of postoperative organ failure. In the present study, modified ultrafiltration (MUF) was applied in cases of adult cardiac surgery and an attempt was made to determine whether MUF reduces serum interleukin-8 (IL-8) levels. Nine patients who underwent cardiovascular surgery with CPB and MUF between June 1996 and June 1997 were compared with nine control patients who underwent cardiovascular surgery without MUF in the same period. Modified ultrafiltration was performed, based on a method proposed elsewhere. Serum IL-8 was measured by enzyme immunoassay at the start of CPB, immediately after CPB, immediately after MUF and 3 h after MUF. The mean filtrated volume was 1550.0 +/- 173.2 ml. In the MUF group, haematocrit increased significantly from 21.2 +/- 2.0 to 24.9 +/- 3.3% (p = 0.0008), while systolic blood pressure increased from 97.5 +/- 16.7 to 116.5 +/- 23.9 mmHg (p = 0.0024) after MUF. In contrast, there were no changes in either haematocrit or blood pressure in the control group. In the MUF group, serum IL-8 was reduced from 69.5 +/- 33.5 to 58.9 +/- 32.4 pg/ml after MUF (p = 0.0029), whereas it was not reduced in the control group. The results of the present study suggest that MUF has beneficial effects on postoperative haemodynamics, and can reduce serum IL-8 levels in adult cardiac surgery.

Beneficial effects of omega-3 fatty acid treatment on the recovery of cardiac function after cold storage of hyperlipidemic rats

Cardiac effects of omega-3 polyunsaturated fatty acids (PUFAs) were studied in female Wister rats fed a standard diet (control [C] diet) or a high-cholesterol (HC) diet. Subgroups of rats from these groups were treated with eicosapentaenoic acid-E (EPA) or docosahexaenoic acid-95E (DHA) for 5 weeks. Although plasma total cholesterol (TC) and triglyceride (TG) levels were higher in each group fed the HC diet versus each group fed the C diet, EPA administration with the HC diet (HC + EPA) significantly (P < .05) reduced these levels. An isolated working-heart preparation was used to determine cardiac function. Cardiac output (CO) was lower in rats fed the HC diet and HC + DHA versus any of the groups fed the C diet (P < .05). In addition, left ventricular (LV) maximum differentiation of pressure-time curve (dp/dt) was lower in the rats fed the HC diet versus any of the C diet groups (P < .05). After evaluation of cardiac function in each rat, the heart was stored in a histidine-tryptophan-ketoglutarate solution for 8 hours at 4 degrees C. The heart was then reperfused, and recovery of cardiac function was evaluated. No significant differences were observed for post-preservative cardiac function within the C diet groups. However, within the HC diet groups, HC + EPA significantly (P < .05) improved the recovery of cardiac function. In addition, HC + DHA also significantly (P < .05) improved the recovery of coronary flow (CF) and LV dp/dt. No significant differences were observed for plasma TC and TG concentrations in the C diet groups. EPA administration significantly decreased cardiac levels of palmitic, oleic, and linoleic acids in the HC diet groups. No significant differences were observed for cardiac levels of free fatty acids (FFAs) within the C diet groups. Cardiac EPA and DHA levels were significantly (P < .05) elevated in EPA- or DHA-treated rats compared with the other diet-fed rats. Cardiac EPA levels were also elevated in DHA-treated rats compared with untreated rats (P < .05). These results suggest that EPA attenuates coronary and myocardial preservation injuries through an increase in serum lipids and an accumulation of myocardial FFAs resulting from a HC diet.

Refractoriness to platelet transfusion following double valve replacement in an ITP patient who had undergone splenectomy

Reports of patients with idiopathic thrombocytopenic purpura (ITP) undergoing cardiac surgery are rare, and almost all of the reported cases required platelet transfusion. ITP patients, especially those having a history of splenectomy or a history of heavy bleeding, may have to undergo multiple platelet transfusions. Such transfusions may induce alloimmunization against the human leukocyte antigen (HLA) and result in refractoriness to subsequent platelet transfusions. We report a case of a 63-year-old female with ITP, with a history of splenectomy and multiple platelet transfusions, who underwent aortic and mitral valve replacement. Although corticosteroid administration, high-dose immunoglobulin therapy, and repeated platelet transfusion led to a temporary increase in platelet count and successful hemostasis, refractoriness to platelet transfusion occurred postoperatively because of the presence of the anti-HLA antibody. In addition, the patient showed complications of pyothorax. Corticosteroids might have exerted an inhibitory influence on the occurrence of pyothorax.

[Application of modified ultrafiltration to cardiac surgery in adults]

Modified Ultrafiltration (MUF) was developed for blood concentration and reduction of postoperative edema in cardiac surgery in children. Its beneficial effects on postoperative hemodynamics have been reported. We applied MUF to cardiac surgery in adults and evaluated its usefulness. Between August, 1995 and April, 1997, MUF was performed in 41 adult patients. MUF was carried out immediately after the cessation of cardiopulmonary bypass. The mean fluid volume removed was 1,135.9 +/- 274.1 ml. The patient's haematocrit significantly increased from 23.2 +/- 2.6% to 26.9 +/- 3.2% (p < 0.0001). The dose of inotropes administered was maintained constant during MUF, and no changes were observed in CVP and the heart rate. However, the systolic blood pressure increased from 99.5 +/- 14.7 to 113.2 +/- 16.2 mmHg (p < 0.0001) and cardiac index from 4.2 +/- 0.9 to 4.9 +/- 1.3 l/min/m2 (p = 0.0006). It was suggested that MUF was an useful technique of haemoconcentration and appeared to have beneficial effects on postoperative hemodynamics in adult cardiac surgery.

Combined catheter embolization and femorofemoral bypass for pseudoaneurysm of the right external iliac artery: report of a case

Performing direct surgery for postoperative hemorrhage caused by intraperitoneal arterial injury is very difficult. We report herein the case of a 52-year-old woman who developed sudden right lower abdominal pain after numerous laparotomies and radiotherapy for advanced uterine cancer. A diagnosis of pseudoaneurysm of the right external iliac artery was made, and an emergency catheter embolization and femorofemoral bypass was successfully performed under local anesthesia. The patient was able to walk the next day. To the best of our knowledge, this is the first report of such a combined procedure in the literature.

[Coronary artery bypass grafting and the repair of ventricular septal defect in idiopathic thrombocytopenic purpura]

A 57-year-old man with idiopathic thrombocytopenic purpura (ITP) underwent coronary artery bypass grafting and repair of ventricular septal defect. He had not been taken any treatments for ITP for the last two years and platelet count was only 26,000 on his admission. He received 5 days of intravenous high dose immunoglobulin therapy but there was no significant increase of platelet count. He received platelet transfusion during and after the surgery resulting in good postoperative course and no problems of hemostasis.

Surgical repair of ventricular septal defect associated with absence of right superior vena cava and persistent left superior vena cava: a case report

A nine-month-old boy, weighing 4840 g, with VSD associated with absent right superior vena cava and persistent left superior vena cava, successfully underwent surgical repair of VSD. This anomaly is rare and causes some surgical and electrophysiological problems. We discussed these problems and described the details of surgery in our case.

[Massive mediastinal bleeding due to spontaneous rupture of the vertebral artery in von Recklinghausen disease]

In Von Recklinghausen disease, patients rarely demonstrate vascular abnormalities, but several reports have noted massive bleeding from vascular rupture. A 28-year-old man with Von Recklinghausen disease was admitted to our hospital because of swelling on the left neck accompanied by dyspnea. Neck and thoracic CT revealed a high density shadow on the mediastinum and left upper thorax which was suspected to indicate hemomediastinum. Under suspicion of bleeding from the intrathoracic artery, the patient underwent on surgery. Massive hematoma disrupted visual recognition of bleeding point, but under anatomical consideration, we concluded that the bleeding was from the ruptured left vertebral artery (VA) which branched independently from the aorta. The left VA was ligated distally and proximally. Left subclavian artery, injured unexpectedly, was not reconstructed but sutured carefully because of its fragility. Thus massive bleeding was controlled. Histology of the neighboring subclavian artery revealed involvement with neurofibrinomatosis. Although the patient's left arm demonstrated a slightly low blood pressure, he was discharged without complaint on the 56th postoperative day.

[Cardiac surgery for the patients with hyperthyroidism]

Since open heart surgery may cause thyrotoxic crisis during the perioperative period in patients with hyperthyroidism, close monitoring and control are needed. We performed open heart surgery in 2 patients with hyperthyroidism, and good results were obtained. A 71-year-old patient with mitral valve insufficiency underwent mitral valve repair by replacement of chordae tendineae with polytetrafluoroethylene sutures and annuloplasty with a Duran's Ring. The other 20-year-old patient with aortic valve insufficiency underwent aortic valve replacement with an SJM valve. In the two patients, cardiopulmonary bypass for a prolonged period was required during surgery. However, thyrotoxic crisis could be prevented by controlling thyroid function by preoperative treatment with anti-thyroid agents, concurrent medication with Lugol's iodine solution immediately before surgery and re-administration of anti-thyroid agents early after surgery.

The relation between arterial oxygen tension and cerebral blood flow during cardiopulmonary bypass

OBJECTIVES

Neurological impairment occurs in up to 25% of infants undergoing cardiopulmonary bypass with or without circulatory arrest. Potential causes include alterations in cerebral blood flow, hypoxia and embolisation. During cardiopulmonary bypass, arterial oxygen tension is maintained at levels which under normal conditions cause cerebral vasoconstriction; this is a potential mechanism for ischaemia. The aim of this study was to explore the relation between arterial oxygen tension and cerebral blood flow during cardiopulmonary bypass.

METHODS

Near infrared spectroscopy was used to explore the relation between arterial oxygen tension and cerebral blood flow in 14 patients (median age 8 months; range 1 month to 10 years 11 months). The relations between arterial oxygen tension, arterial carbon dioxide tension, temperature, haematocrit, pump flow rate, mean arterial pressure and cerebral blood flow, were examined using multivariate analysis.

RESULTS

There was no relation between cerebral blood flow and arterial oxygen tension, but a highly significant relation was observed between cerebral blood flow and pump flow rate, with cerebral blood flow decreasing 4.2-fold per L.m-2.min-1 decrease of pump flow rate.

CONCLUSION

There was no relation between arterial oxygen tension and cerebral blood flow during cardiopulmonary bypass, but low pump flow rate may lead to reduced cerebral blood flow.

Supravalvular stenotic mitral ring with ventricular septal defect

BACKGROUND

Supravalvular mitral ring is exceedingly uncommon.

METHODS

We report a 4-year-old girl with supravalvular stenotic mitral ring and ventricular septal defect (VSD). The VSD was closed by a Dacron patch and the supravalvular ring was excised. For treatment of supravalvular mitral ring with obstruction, surgical resection is commonly performed.

RESULTS

There are no reports of long-term follow-up after resecting the supravalvular mitral ring.

CONCLUSION

In our case, no mitral stenosis was evident on postoperative echocardiogram performed 3 years after surgery.

Myxoma of the aortic valve

Myxoma of the aortic valve is exceedingly uncommon. In this article, we report a 58-year-old man with myxoma arising from the aortic valve. Aortic valve replacement was performed, and postoperative histologic examination showed myxoma of aortic valve.

Pseudoaneurysm of the left ventricle following repair for ventricular septal perforation

The patient was a 64-year-old man who was treated surgically for an infarct-related ventricular septal perforation. Pseudoaneurysm of the left ventricle was recognized on the 38th postoperative day. Emergency surgery was performed. It seemed that insufficient resection of the infarcted myocardium was performed during the initial surgery to avoid narrowing the ventricular dimension by direct closure of the left ventricle, but this resulted in pseudoaneurysm of the left ventricle. Left ventricular free wall plasty with a patch should be performed during the initial surgery.

[Successful repair of right atrial rupture due to nonpenetrating trauma of the chest]

A 24-year-old male was brought to our hospital after being injured in a traffic accident. On arrival, his blood pressure was 70/44 mmHg and his pulse rate was 135/min and regular. Chest X-p revealed cardiomegaly but there was no pleural effusion or bone fracture. Echocardiogram revealed cardiac tamponade and he was diagnosed as cardiac rupture due to non penetrating trauma. Under midline sternotomy, right atrial rupture was repaired. The patient developed cardiac arrest lasting approximately 8 minutes during anesthetic induction, so he needed to be ventilated for 8 days. However his postoperative course was not so eventful and he was discharged 38 days after surgery without any neurophysiological disturbance.

Effects of auricular acupuncture stimulation on nonobese, healthy volunteer subjects

Effects of auricular acupuncture stimulation on nonobese healthy volunteers were investigated. Subjects (n = 35) averaged 34.5 years old, and BMI was 25.3 kg/m2. Small (0.15 x 2.0 mm) auricular needles were applied intracutaneously into the bilateral cavum conchae that was identified by having less than 100 k omega resistance. Body weight was measured four times a day and charted by the subjects themselves. Results showed that, in the period 11-2, in which only body weight was measured, without auricular acupuncture stimulations, 57.1% of the subjects reduced their body weight. This indicates that charting body weight themselves might be useful to maintain their weight. In the auricular acupuncture treated period, 19 (70.4%) out of 27 decreased (p < 0.01), 5 (18.5%) was increased, and 3 (11.1%) had no change in body weight. In conclusion, the results suggest that success in maintaining weight reduction can be attributed to graphic illustration of one's weight pattern. Bilateral auricular acupuncture stimulation can also reduce body weight of healthy non-obese subjects. This is consistent with the suggestion that it might be effective in the treatment of obese patients.

Clinical significance of reverse redistribution phenomenon after coronary artery bypass grafting

The reverse redistribution (RR) phenomenon is a decrease in thallium 201 uptake during redistribution compared with 201Tl uptake immediately after exercise. We evaluated RR in 23 patients after coronary artery bypass grafting. Postoperative RR was present in 48% and was significantly more common in patients with a history of myocardial infarction (62%). The patients were classified according to the presence (+) or absence (-) of RR. An analysis of left ventricular wall motion showed significant improvement after coronary artery bypass grafting in the RR+ group (n = 12) but not in the RR- group (n = 11). Quantitative myocardial viability was evaluated using the defect volume ratio, mean defect severity, and defect severity index. The preoperative defect volume ratio was higher in the RR+ group than in the RR- group (p < 0.05). In the RR- group, no improvement in these indices was observed after operation. In contrast, the RR+ group showed significant improvement in all three indices (p < 0.05). These results indicate that after coronary artery bypass grafting, an adequate blood supply to the remaining myocardium may induce RR. This phenomenon, therefore, may be a significant indicator of postoperative myocardial viability.

Surgical repair of a ventricular septal defect in a patient with trisomy 8 syndrome

We surgically repaired a ventricular septal defect (-VSD) in a patient with trisomy 8 syndrome. This case illustrated a number of characteristic clinical features associated with trisomy 8 syndrome patients which have previously been reported in the literature. However, our patient's VSD was not found to be particularly different from the VSD of patients without chromosomal abnormalities during either the surgery or the postoperative course.

Effects of hypothalamic paraventricular nucleus: electrical stimulation produce marked analgesia in rats

The effect of the electrical simulation induced analgesia (ESIA) on the hypothalamic paraventricular nucleus (PVN) was investigated by the paw pressure test, which was used to avoid any tissue damage to the paw of Wistar-SPF/VAF male rats. A stimulating electrode was chronically implanted in the parvocellular (PVN-prv) or magnocellular (PVN-mgn) divisions of the PVN. The ESIA was examined at least 10 days after surgery. The electrical stimulation of the PVN markedly showed analgesia (ESIA), but stimulation of most locations outside the PVN did not produce ESIA. Stimulation threshold for the ESIA was lower from PVN-prv than from PVN-mgn, but neither region was affected by naloxone administration (10 mg/kg, i.p.). These results indicate that the PVN is a part of the pain inhibitory system in the CNS, and show that PVN-ESIA might not be mediated either by opioids or by neuropeptides such as vasopressin.

Effects of auricular stimulation on feeding-related hypothalamic neuronal activity in normal and obese rats

It is known that auriculotherapy occasionally affects dramatic body weight reduction for obese patients, although the physiological and anorexigenic functions are not clear. Effects of auricular stimulation on feeding-related lateral (LHA) and ventromedial (VMH) hypothalamic neuronal activity in normal and experimental (hypothalamic and dietary) obese rats were investigated. The LHA and/or VMH neuronal activity were recorded from feeding-related regions in Wistar SPF/VAF male and experimental (hypothalamic and dietary) obese rats, anesthetized with urethane-chloralose, under stereotaxic coordination. Recording was through 3 M KCI glass microelectrodes, while stimulating the ipsilateral vagal innervated region of the auricle. This is equivalent to the cavum conchae in the human, and was identified by resistance less than 10-50 k omega. The stimulating electrode was a stainless steel ear acupuncture (0.12 x 2.0 mm). The latency of potentials evoked in the LHA by unilateral stimulation of a specific site in the ear was 28.1 +/- 3.3 ms (8-92, n = 41). LHA neuronal activity was depressed 45.6% (n = 12, p < 0.01), and VMH activity was excited (60.5%, n = 18, p < 0.01). The auricular acupuncture stimulation clearly modulates feeding-related hypothalamic neuronal activity of experimental (both hypothalamic and dietary) obese rats. These auricle acupuncture stimulation effects were correlated to the degree of obesity. In conclusion, the results suggest that auricular acupuncture stimulation may not reduce appetite, but is more likely concerned with satiation formation and preservation. Thus, auricular acupuncture should be more effective on obese rats than on normal rats.

A clinical study on the effects of pulsatile cardiopulmonary bypass on the blood endotoxin levels

Levels of endogenous endotoxins have been reported to increase after cardiopulmonary bypass. Endotoxin levels have also been implicated in multiple organ failure and may contribute to the immunocompromised state seen after bypass. We evaluated the effects of pulsatile cardiopulmonary bypass circulation on endogenous endotoxin levels. The study population consisted of 15 consecutive adult patients who underwent cardiac operations with cardiopulmonary bypass. Pulsatile flow was used during aortic crossclamping in eight patients (group I) and nonpulsatile flow was used in the remaining seven patients (group II). Changes in blood endotoxin levels were monitored during aortic crossclamping, after release of the clamp, and after weaning from bypass. The blood endotoxin level at each stage was expressed as a percentage of the level at the beginning of bypass. Group I patients a significantly lower blood endotoxin percentage than group II (from 20 to 120 minutes after the initiation of aortic crossclamping). In group I, the blood endotoxin percentage was nearly constant during aortic crossclamping. After release of aortic crossclamping, group I also had a lower blood endotoxin percentage than group II. Endogenous endotoxin levels appear to increase in the presence of intestinal congestion and ischemia. Improvement in intestinal circulation by pulsatile cardiopulmonary bypass may prevent increases in endogenous endotoxin levels by reducing these factors.

Optimal perfusion pressure for experimental retrograde cerebral perfusion

We evaluated cerebral metabolism during retrograde cerebral perfusion (RCP) and circulatory arrest during profound hypothermia, and also investigated the effects of perfusion pressure on RCP. Twenty-four adult mongrel dogs were placed on cardiopulmonary bypass and cooled to a nasopharyngeal temperature of 20 degrees C. At this temperature, hypothermic circulatory arrest (HCA; n = 6), and RCP with a perfusion pressure of 10 mmHg (RCP10; n = 6), 20 mmHg (RCP20; n = 6), and 30 mmHg (RCP30; n = 6) were carried out for 60 minutes. RCP was performed with oxygenated blood via the bilateral maxillary veins, and the retrograde flow rate was regulated to maintain a mean perfusion pressure of 10, 20, or 30 mmHg in the external jugular vein. At 60 minutes of RCP, we measured nasopharyngeal temperature; regional cerebral blood flow (rCBF); cerebral oxygen consumption, carbon dioxide excretion, and excess lactate; cerebral tissue adenosine triphosphate (ATP), adenosine diphosphate (ADP), adenosine monophosphate (AMP) and energy charge; and cerebral tissue water content. In the RCP10 group, there was excess cerebral lactate, and ATP and energy charge were low. In the RCP30 group, the water content of cerebral tissue was significantly higher than in other groups. In the RCP20 group, temperature was maintained in a narrow range, oxygen consumption and carbon dioxide excretion could be observed, there was no excess lactate, and ATP and energy charge were significantly higher than in the HCA group. In conclusion, RCP can provide adequate metabolic support for the brain during circulatory arrest, and a perfusion pressure of 20 mmHg is most appropriate for RCP.

[Experimental study of optimal perfusion pressure during retrograde cerebral perfusion]

The effects of retrograde perfusion pressure on the brain was experimentally investigated during profound hypothermic circulatory arrest. Fifteen adult mongrel dogs were placed cardiopulmonary bypass and induced profound hypothermia of 20 degrees C at nasopharyngeal temperature. Retrograde cerebral perfusion (RCP) with perfusion pressure of 10 mmHg (RCP10; n = 5), 20 mmHg (RCP20; n = 5), 30 mmHg (RCP30; n = 5) underwent for 60 minutes. The oxygenated blood was infused via the bilateral maxillary veins, and the flow rate was kept to maintain a desired pressure in the external jugular vein for each group. Regional cerebral blood flow (rCBF), excess lactate, cerebrospinal fluid pressure (CSFP), adenosine triphosphate (ATP) concentration of cerebral tissue, and water content of cerebral tissue were measured. In the RCP10 group, cerebral excess lactate was positive and ATP concentration was low. In the RCP30 group, the water content of cerebral tissue was significantly higher than those in the other groups. In the RCP20 group, the excess lactate was maintained in a negative range, and ATP concentration was significantly higher than in the RCP10 group. In conclusion, RCP may provide metabolically adequate support for the brain and a perfusion pressure of 20 mmHg was appropriate for RCP in dogs.