Yoshifumi Iguro

Mechanism of Recurrent/Persistent Ischemic/Functional Mitral Regurgitation in the Chronic Phase After Surgical Annuloplasty Importance of Augmented Posterior Leaflet Tethering

Background— Surgical annuloplasty can potentially hoist the posterior annulus anteriorly, exaggerate posterior leaflet (PML) tethering, and lead to recurrent ischemic/functional mitral regurgitation (MR). Characteristics of leaflet configurations in late postoperative MR were investigated. Methods and Results— In 30 patients with surgical annuloplasty for ischemic MR and 20 controls, the anterior leaflet (AML) and PML tethering angles relative to the line connecting annuli, posterior and apical displacement of the coaptation and the MR grade were measured by echocardiography before, early after, and late after surgery. Early after surgery, grade of MR and AML tethering generally decreased (P<0.01), whereas PML tethering significantly worsened (P<0.01). Nine of the 30 patients showed recurrent/persistent MR late after surgery. Compared with patients without late MR, those with the MR showed similar reduction in the annular area, significant re-increase in posterior displacement of the coaptation, and progressive worsening in PML tethering (P<0.05) late after surgery in comparison to the early phase. Both preoperative MR and late postoperative MR were significantly correlated with all tethering variables in univariate analysis. Although apical displacement of the coaptation was the primary determinant of preoperative MR (r2=0.60, P<0.0001), increased PML tethering was the primary determinant of late MR (r2=0.75, P<0.0001). Conclusions— Whereas both leaflets tethering is related to preoperative ischemic MR, both leaflets tethering but with predominant contribution from augmented and progressive PML tethering is related to recurrent/persistent ischemic/functional MR late after surgical annuloplasty.

Operation for adult patent ductus arteriosus using cardiopulmonary bypass.

BACKGROUND Surgical repair of adult patent ductus arteriosus is more hazardous than when performed on young patients. METHODS Nine adult patent ductus arteriosus patients underwent surgical repair between January 1986 and December 1998. There were 3 male and 6 female patients (mean age 55.0 years). The ratio of pulmonary blood flow to systemic flow was 2.40 +/- 0.95, and pulmonary arterial pressure was 56.0 +/- 26.4 mm Hg. The operation was performed using transpulmonary approach under total cardiopulmonary bypass. Balloon occlusion method was also utilized. RESULTS Direct closure was made in 5 and patch closure in 4 patients. Cardiopulmonary bypass and balloon occlusion were safely established. Cardioplegic arrest was not required in the 2 most recent patients. No operative death has occurred. Pulmonary arterial systolic pressure decreased to 35.3 +/- 6.6 mm Hg at 6 months after operation. The mean follow-up period for all patients is 55 months. To date, neither recannalization of the ductus nor pseudoaneurysm has been recognized. CONCLUSIONS Cardiopulmonary bypass with balloon occlusion provides a safe operation for adult patients with complicated patent ductus arteriosus.

Penetrating atherosclerotic ulcer.

Abstract The pathogenesis of penetrating atherosclerotic ulcer (PAU) in aortic disease remains controversial. Between January 1995 and April 1999, five patients underwent treatment for a PAU in our hospital. All were men, ranging in age from 46 to 74 years, with a mean age of 66.2 years. The PAU was located on the thoracic descending aorta in three patients and on the abdominal aorta in two. Preoperative diagnosis was established by contrast-enhanced computed tomographic scan and aortogram. Surgery was performed in four patients, as graft replacement in three, and patch plasty in one. The remaining patient is being carefully observed on antihypertensive therapy. No connective tissue disorder, trauma, dissection, or infection was seen in any of the patients who underwent surgery, all of whom had uneventful postoperative courses with no perioperative complications or enlargement of the aorta. We conclude that surgical treatment should be performed for patients with PAU to prevent an aortic catastrophe caused by rapid development of the lesion. This report might provide further evidence of the importance of PAU.

Evaluation of anti-platelet aggregatory effects of aspirin, cilostazol and ramatroban on platelet-rich plasma and whole blood.

To compare property in anti-platelet effects of aspirin (a cyclooxygenase inhibitor), cilostazol (a phosphodiesterase III inhibitor) and ramatroban (a specific thromboxane A2 receptor antagonist), we measured human platelet-rich plasma (PRP) aggregation induced by adenosine diphosphate (ADP), collagen and arachidonic acid, and whole blood (WB) aggregation induced by ADP. The release of P-selectin, transforming growth factor-beta 1, and the formation of thromboxane A2 in response to agonists were also investigated. Inhibitory effects of 100 μmol/l aspirin, 10 μmol/l cilostazol and 1 μmol/l ramatroban on 5 μmol/l ADP-induced PRP aggregation were similar. However, aspirin strongly inhibited thromboxane A2 formation in response to 5 μmol/l ADP compared with other drugs. Inhibitory effects of 10 μmol/l cilostazol on PRP aggregation and the release of molecules were quite similar in responsiveness induced by the three agonists. Aspirin and cilostazol inhibited platelet aggregation in a concentration-dependent, non-linear fashion, while ramatroban inhibited linearly with increasing concentration. Anti-platelet effects of drugs having different pharmacological mechanisms were demonstrated clearly by measuring PRP aggregation induced by the three agonists, and by measuring WB aggregation that most probably reflects not only platelet–platelet interactions, but also platelet–leukocyte interactions, as well as the release of intraplatelet molecules.

Clinical Experience with Temporary Vena Cava Filters

An experience with temporary filter placement, which seems to be safe and effective for temporarily preventing pulmonary embolism, is reported. Since October 1997, six patients had temporary filters. There were two men and four women, with a mean age of 37 years. Three filters were placed at the infrarenal inferior vena cava, two at the suprarenal inferior vena cava, and one at the superior vena cava. All filters were placed before various surgical interventions. During filter placement, anticoagulation therapy was routinely performed. There were no complications at and during filter placement. No pulmonary emboli occurred during surgical intervention. All filters were successfully removed, two of which were exchanged for permanent filters. All patients are alive and well without recurrent deep vein thrombosis and/or pulmonary emboli during a follow-up period of 11 to 25 months. Although this experience is small, temporary filter placement is safe and effective for short-term prevention of pulmonary emboli even in older patients or those with malignant disease. Veins of the upper part of the body may be more favorable than the femoral vein for insertion of a temporary filter. Temporary filters can be safely placed not only at the infrarenal inferior vena cava, but also at the suprarenal inferior vena cava or superior vena cava.

Thoracic and thoracoabdominal aneurysm repair under deep hypothermia using subclavian arterial perfusion

BACKGROUND Hypothermic circulatory arrest is a valuable adjunct for thoracic and thoracoabdominal aortic aneurysm repair. Retrograde aortic perfusion through the femoral artery, however, carries a risk of cerebral embolism or malperfusion. To avoid these complications we adopted antegrade aortic perfusion through a prosthetic graft attached to the left subclavian artery through a left thoracotomy. METHODS Ten patients had repair of descending thoracic and thoracoabdominal aortic aneurysm under deep hypothermia with antegrade aortic perfusion through the left subclavian artery. Hypothermic circulatory arrest was used because proximal aortic control was hazardous due to rupture or intraluminal disease, or for spinal cord protection. RESULTS There was no brain injury and one hospital death. The cause of death was massive bleeding from the gastrointestinal tract not related to deep hypothermia or the perfusion method. All 9 survivors were alive and well after a mean follow-up period of 9 months. CONCLUSIONS Using the left subclavian artery as a site of aortic perfusion can avoid retrograde aortic perfusion, hence reducing the potential for brain injury due to embolic stroke or malperfusion through a dissected thoracoabdominal aorta.

Successful management of uterine arteriovenous malformation by ligation of feeding artery after unsuccessful uterine artery embolization

Uterine arteriovenous malformation (AVM) is a rare and potentially life‐threatening disease. The present report describes a postmenopausal patient with uterine AVM manifesting recurrent, massive genital bleeding. Uterine artery embolization (UAE) was scheduled before hysterectomy, but UAE was unsuccessful due to the dilated, tortuous internal iliac arteries, and extremely rapid arterial blood flow. Hysterectomy appeared to carry a potential risk of massive blood loss due to multiple dilated vessels around the uterine corpus and cervix. Therefore, six arteries feeding the uterus were surgically ligated. At 10 months after the operation there have been no episodes of atypical genital bleeding.

Aortoenteric fistula after endovascular stent grafting for an abdominal aortic aneurysm: report of a case.

We report a case of an aortoenteric fistula (AEF) developing after endovascular stent grafting (EVSG) for an abdominal aortic aneurysm (AAA). A 69-year-old male patient with a history of panperitonitis caused by rectal perforation underwent EVSG for an AAA. A follow-up contrast-enhanced computed tomography (CT) scan, done 12 months after the EVSG, confirmed shrinkage of the AAA with no endoleak. However, 19 months postoperatively, an AEF developed between the AAA and the jejunum. Although there was no endoleak on a subsequent CT scan, we noted enlargement of the AAA and inflammatory changes in the surrounding tissue. The patient was treated surgically and discharged in good health 74 days postoperatively. Thus, one should consider the possibility of this devastating complication, even in patients without an endoleak, after EVSG for AAA.

Superior Vena Caval Placement of a Temporary Filter A Case Report

Placement of permanent filters in the superior vena cava (SVC) for preventing pulmonary embolism (PE) arising from thrombi superior to the right atrium has rarely been performed. The authors report the first case of temporary filter insertion in the SVC because of upper extremity thrombosis accompanied with PE. After thrombectomy, the temporary filter was successfully removed. It is recommended to use a temporary filter, especially in young patients with upper extremity thrombosis requiring temporary prophylaxis against PE.

Pasteurella multocida Endocarditis: Report of a Case

The present case involves a 48-year-old male patient who presented with Pasteurella multocida endocarditis associated with preexisting mitral valve stenosis. A mitral valve replacement was successfully performed after 3 weeks of intravenous infusion with antibiotics. Pasteurella multocida is a normal inhabitant of the oral cavity of dogs and cats. Therefore, people who have frequent contact with these animals should be examined periodically for signs of infection.