Wakako Fukuda

Infective endocarditis with cerebrovascular complications: timing of surgical intervention

Management of infective endocarditis (IE) with cerebrovascular complications is difficult due to absence of concrete evidence. These patients usually have multiple neurological deficits and the optimal timing for cardiac operation remains controversial. The aims of this study were to present cases and discuss the treatment options for IE with cerebrovascular complications. From 1998 to 2010, 51 patients underwent operations for IE at our institution. From a review of medical records, 10 patients (19.6%) with preoperative neurological complications were identified. Data on these 10 patients were analysed. Cerebrovascular complications included cerebral infarction (n = 4, 40.0%), mycotic aneurysm (n = 1, 10.0%), mycotic aneurysm plus cerebral infarction (n = 3, 30.0%), meningitis (n = 1, 10.0%) and mycotic aneurysm with cerebral haemorrhage plus meningitis (n = 1, 10.0%). Of 5 patients having mycotic aneurysms, 3 underwent clipping before cardiac operations. The mean interval from craniotomy to cardiac operations was 26.7 ± 21.8 days. A cardiac operation was performed initially on seven patients. The mean interval from the onset of neurological deficit to cardiac operation was 7.4 ± 9.8 days. The mortality rate was 10.0%. Postoperative deterioration was not observed. Management of IE with cerebrovascular complications should be based on case-by-case multidisciplinary assessment of potential risks and benefits of intracranial and cardiac operations.

Outcome of pulmonary embolectomy for acute pulmonary thromboembolism: analysis of 32 patients from a multicentre registry in Japan.

OBJECTIVE Massive pulmonary embolism is relatively rare but a potentially life-threatening condition. The purpose of this study was to analyse the outcome of pulmonary embolectomy in registered data from the Japanese Society of Pulmonary Embolism Research (JaSPER). METHODS From 1994 to 2006, 1661 cases of acute pulmonary embolism were registered in the JaSPER database. Retrospective analysis of 32 patients undergoing pulmonary embolectomy was conducted. The overall incidence of pulmonary embolectomy was 1.9% [95% confidence interval (CI): 1.8-3.2%]. The mean age of patients was 57 years and 66% were female. RESULTS Overall mortality of pulmonary embolectomy was 18.8% [95% CI: 5.2-25.6%]. Most of the patients had massive or submassive pulmonary thromboembolism, and three patients experienced cardiopulmonary arrest before embolectomy. Ten patients received preoperative percutaneous cardiopulmonary bypass, and mortality was 30% in this subgroup. CONCLUSIONS Pulmonary embolectomy is an effective therapeutic option for patients with massive or submassive pulmonary embolism. Prompt triage of patients with haemodynamic instability is important.

Shaggy and calcified aorta: surgical implications

Atheroembolism is an emerging problem in cardiovascular surgery, especially in elderly patients. Severe atherosclerosis of the thoracic aorta usually reflects systemic atherosclerosis. Aggressive preoperative and intraoperative evaluation of the aorta using enhanced CT, transesophageal echocardiography and epiaortic ultrasound is important in elderly patients as well as those with systemic atherosclerosis. To prevent atheroembolism, it is important to select an adequate arterial perfusion site and to avoid touching the diseased aorta until circulatory arrest. In atherosclerotic aortic arch aneurysm, central cannulation under ultrasound guidance and directing the dispersive cannula toward the aortic root is a simple and effective perfusion strategy. Axillary perfusion is useful as an alternative to central cannulation in atherosclerotic aortic disease, but special care is necessary to avoid complications when the patient has a small axillary artery or flail atheroma around the arch vessels. In femoral artery perfusion, retrograde perfusion may induce paradoxical cerebral embolism, but the incidence of stroke is comparable with axillary perfusion when there is adequate preoperative screening using transesophageal echography. Circulatory arrest with/without cerebral perfusion is another important strategy when the aorta has severe atherosclerosis. Recent literature has shown that mild hypothermia may be safe for anterior cerebral perfusion during circulatory arrest, but optimal flow rates and time limitations are unknown. A simple calcified aorta called “porcelain aorta” may be managed by circulatory arrest, local debridement and the clamp method. Several surgical options are proposed for this clinical entity but their use will diminish in the future because of transcatheter valve replacement.

Acute limb ischemia: contemporary approach

Acute limb ischemia is a critical condition with high mortality and morbidity even after surgical or endovascular intervention. Early recognition is important, but a delayed presentation is not uncommon. Viability of the limb is assessed by motor and sensory function and with interrogating Doppler flow signals in pedal arteries and popliteal veins as categorized by Rutherford. Category IIa indicates mild-to-moderate threat to limb salvage over a time frame without revascularization. Limb ischemia is critical without prompt revascularization in category IIb. Because the risk of reperfusion injury is high in this group of patients, perioperative management is important. In category III, reperfusion is not indicated except for embolism within several hours of onset. Intimal injury should be avoided by careful tactile control of a balloon with a smaller size catheter and under radiographic monitoring. Adjunctive treatment with catheter-directed thrombolysis or bypass surgery is sometimes necessary. Endovascular treatment is a promising option for thrombotic occlusion of an atherosclerotic artery. Ischemia-reperfusion injury is a serious problem. Controlled reperfusion with low-pressure perfusion at a reduced temperature and use of a leukocyte filter should be considered. The initial reperfusate is hyperosmolar, hypocalcemic, slightly alkaline, and contains free radical scavengers such as allopurinol. Immediate hemodialysis is necessary for acute renal injury caused by myoglobinemia. Compartment syndrome should be managed with assessment of intra-compartment pressure and fasciotomy.

Vacuum-assisted venous drainage in tricuspid valve re-replacement

The number of reoperations for prosthetic valve replacement has increased in recent years due to the steady increase in life expectancy. However, reoperations are complex and require experience and skills. We report the case of a 69-year-old female with severe right heart failure who underwent tricuspid valve re-replacement 28 years after the initial tricuspid valve replacement. Cardiopulmonary bypass with vacuum-assisted venous drainage (VAVD) was used to achieve better perfusion flow and heart decompression with smaller venous cannulae. The operation was successful. The VAVD system is effective in patients who have a persistent elevation of central venous pressure.

Endovascular Treatment of Ruptured Intercostal Arteriovenous Fistulas Associated with Neurofibromatosis Type 1

Wereport a rare case of ruptured intercostal arteriovenous fistula in a patient with neurofibromatosis type 1. The patient presented with severe back pain. Angiography revealed ruptured intercostal arteriovenous fistulas. Successful coil embolization to occlude the fistulas and the aneurysm resulted in successful recovery of the patient.

Improved Outcomes for Ruptured Abdominal Aortic Aneurysms Using Integrated Management Involving Endovascular Clamping, Endovascular Replacement, and Open Abdominal Decompression

Objective: Endovascular repair has become the treatment of choice for ruptured abdominal aortic aneurysms (RAAAs). To improve surgical outcomes, preoperative management is important. In 2011, we introduced integrated management, which involves endovascular aneurysm repair, stabilization of hemodynamics by endovascular clamping, and open abdominal decompression to address abdominal compartment syndrome (ACS). Methods: To evaluate the efficacy of this management strategy, 62 patients who had undergone emergency surgery for an RAAA were analyzed retrospectively: group A (n=39), where an old strategy was used, and group B (n=23), where integrated management was introduced. Patient characteristics and 30-day mortality rates were compared between the two groups. Results: The average patient age was 67.7 years and 74.7 years for groups A and B, respectively (P=0.032). Group B patients required more frequent use of vasopressors (P=0.035). Other patient characteristics did not differ between the two groups. The duration of surgery was significantly shorter in group B than in group A (P=0.001). The total amount of transfused blood did not differ between the two groups. No patients showed symptoms of ACS. Early mortality rates were 12.8% and 8.7% in groups A and B, respectively. The number of wound infections was significantly fewer in group B than in group A. Conclusion: Although group B patients were significantly older and had a higher rate of vasopressor use, early mortality was improved in both groups. Morbidity was significantly better in group B with respect to the duration of surgery and number of wound infections than in group A.

Surgical Management of Mycotic Aortic Aneurysms

Purpose: A mycotic aneurysm is an uncommon disease associated with a high mortality rate when managed surgically. This study reviewed our experiences in the surgical management of mycotic aortic aneurysms. Methods: In total, 26 patients who underwent surgery for a mycotic aneurysm were retrospectively reviewed. The mycotic aneurysms involved the thoracic aorta in 9 patients, the thoracoabdominal aorta in 4 patients, and the abdominal aorta in 13 patients. An overt aortic rupture in the mediastinum or retroperitoneal space was detected in 4 patients. Patients were classified into one of two groups, febrile or afebrile, and background characteristics, surgical intervention, and early and late mortalities were all compared. Results: There were 19 patients who underwent open surgery, and 7 patients underwent endovascular repair. No significant differences in the clinical characteristics were found between the two groups; however, the incidence of postoperative complications was significantly higher in the febrile group than in the afebrile group (P=0.024). Overall mortality was 15.4% (4/26), and 30-day mortality was 7.7% (2/26). Conclusion: Although febrile patients had a higher incidence of postoperative complications, surgical mortality from a mycotic aneurysm was within an acceptable range. Each patient should be thoroughly evaluated and treated on a case-by-case basis, using conventional open repair, endovascular repair, or a combination of both approaches.

Intimal sarcoma of the pulmonary artery--diagnostic challenge.

Pulmonary artery intimal sarcoma is a rare tumour and the diagnosis is often delayed. We report the case of a woman with a primary pulmonary artery intimal sarcoma who presented with massive pulmonary embolism. The defi nitive diagnosis was elucidated after the patient’s death by autopsy specimen. We discuss the diagnosis and lessons learned from this case.

Effect of inflow cannula side-hole number on drainage flow characteristics: flow dynamic analysis using numerical simulation

Background: Venous drainage in cardiopulmonary bypass is a very important factor for safe cardiac surgery. However, the ideal shape of venous drainage cannula has not been determined. In the present study, we evaluated the effect of side-hole number under fixed total area and venous drainage flow to elucidate the effect of increasing the side-hole numbers. Method: Computed simulation of venous drainage was performed. Cannulas were divided into six models: an end-hole model (EH) and models containing four (4SH), six (6SH), eight (8SH), 10 (10SH) or 12 side-holes (12SH). Total orifice area of the side-holes was fixed to 120 mm2 on each side-hole cannula. The end-hole orifice area was 36.3 mm2. The total area of the side-holes was kept constant when the number of side-holes was increased. Result: The mean venous drainage flow rate of the EH, 4SH, 6SH, 8SH, 10SH and 12SH was 2.57, 2.52, 2.51, 2.50, 2.49, 2.41 L/min, respectively. The mean flow rate decreased in accordance with the increased number of side-holes. Conclusion: We speculate that flow separation at the most proximal site of the side-hole induces stagnation of flow and induces energy loss. This flow separation may hamper the main stream from the end-hole inlet, which is most effective with low shear stress. The EH cannula was associated with the best flow rate and flow profile. However, by increasing side-hole numbers, flow separation occurs on each side-hole, resulting in more energy loss than the EH cannula and flow rate reduction.