Can Low-dose Irradiation of Donor Hearts before Transplantation Inhibit Graft Vasculopathy? / 日本心臓血管外科学会雑誌

This experimental study was conducted to histopathologically determine whether the low-dose irradiation of donor hearts before transplantation can inhibit graft vasculopathy. Immediately after donor F 344 rat hearts were removed, they were treated with a single dose of radiation using 7.5Gy, 15Gy, or no radiation (control group). The F 344 hearts were transplanted into Lewis rats heterotopically, and cyclosporine A was injected intramuscularly for 20 days after transplantation in all groups. The hearts were harvested 90 days after transplantation, and examined for intimal thickening using elastica van Gieson staining. Severe intimal thickening was observed in both the irradiated groups, the percent intimal area of the coronary arteries was significantly increased in both these groups, to 34.3±12.9 in the 7.5Gy group and 37.0±8.9 in the 15Gy group, compared with 23.1±9.8 in the control group (<i>p</i><0.01). In conclusion, these findings show that low-dose irradiation to donor hearts before transplantation does not inhibit graft vasculopathy.

Prognosis of Stanford Type A Acute Aortic Dissection without Aortic Reconstruction / 日本心臓血管外科学会雑誌

Six cases without aortic reconstruction for 48 hours were encountered among 22 cases of Stanford type A acute aortic dissection from April, 1990 to July, 1996. They were one man and five women, with a mean age of 60.3 years old (from 52 to 82 years old). According to Hagiwara's definition, acute thrombotic aortic dissection (ATAD) was observed in four and acute opacified aortic dissection (AOAD) in two of six cases of Stanford type A acute aortic dissection without aortic reconstruction. One of the four ATAD cases was well-controlled by medical therapy, but the others could not be controlled and underwent aortic root reconstruction within 1 month. Two AOAD patients died due to rupture within 1 month. It is said in general that the patients with acute thrombotic aortic dissection can be treated medically, but we consider that they should be treated surgically because of the frequency of late rupture.

Surgical Treatment of Multiple Aneurysms / 日本心臓血管外科学会雑誌

Morphology, location, timing of operation, and complications of multiple aortic aneurysms were investigated in 14 patients (10 men and 4 women with a mean age of 66 years). The locations of the aneurysms were as follows: aortic arch and thoracoabdominal aorta in 1, aortic arch and infrarenal abdominal aorta in 6, descending thoracic aorta and suprarenal abdominal aorta in 1, descending thoracic aorta and infrarenal abdominal aorta in 5, and thoracoabdominal aorta and infrarenal abdominal aorta in 1. Thoracic aortic aneurysms had a mean diameter of 63±13mm. The mean diameter of the abdominal aortic aneurysms was 54±13mm. In 1 patient, thoracoabdominal and infrarenal abdominal aortic aneurysms were operated on simultaneously. Eight patients, 5 with aneurysms of the aortic arch and infrarenal abdominal aorta, 2 with aneurysms of the descending aorta and infrarenal abdominal aorta, and 1 with aneurysms of the aortic arch and thoracoabdominal aorta, underwent two-staged operation. Aortic arch aneurysm was operated first in 3 patients, and abdominal aortic aneurysm in 5. Postoperative complications included spinal cord injury in 1 patient, bowel necrosis in 1, renal impairment in 2, respiratory impairment in 2, and hepatic impairment in 1. There was no perioperative death. Three late deaths occurred. Two staged operation is better for multiple aortic aneurysms. The first operation should be performed for the larger aneurysm.

Surgical Results and Quality of Life in Stanford Type A Aortic Dissection / 日本心臓血管外科学会雑誌

From April 1990 to August 1995, 44 consecutive patients (25 males and 19 females; mean age, 63 years) who underwent surgery for Stanford type A aortic dissection, were studied to examine surgical results and postoperative quality of life (QOL). Ascending aortic replacement was performed in 22 patients and simultaneous replacement of the ascending aorta and the aortic arch in 22. The postoperative 30-day survival rate was 84% (37/44). Univariate analysis revealed that operation time (<i>p</i><0.01), postoperative cardiac failure (<i>p</i><0.02), respiratory failure (<i>p</i><0.01), severe brain damage (<i>p</i><0.01), and intestinal ischemia (<i>p</i><0.02) were significant factors in increased operative mortality risk. Additional operative procedure was also a significant factor (<i>p</i><0.05) all 3 patients with coronary artery bypass grafting died, while all 5 patients with the Bentall or Cabrol procedure lived. The factors which influenced postoperative QOL were preoperative renal damage (<i>p</i><0.05), history of cerebral vascular disease (<i>p</i><0.02), shock (<i>p</i><0.02), postoperative renal failure (<i>p</i><0.02), paraplegia (<i>p</i><0.02), and residual dissection (<i>p</i><0.02). The operation method, which was replacement of the ascending aorta or simultaneous replacement of the ascending aorta and the aortic arch, had no influence on postoperative QOL. Five of 22 patients receiving ascending aorta replacement had dissection only in the ascending aorta (localized type). The other 17 patients receiving ascending aorta replacement had dissections extending to the arch or descending aorta. The incidence of complications due to residual dissection was 5/17 (29%) in cases of replacement of the ascending aorta for type A aortic dissection, while it was 1/22 (5%) in cases of replacement of the ascending aorta and the aortic arch (<i>p</i>=0.0684). Simultaneous replacement of the ascending aorta and the aortic arch did not negatively affect the surgical results and postoperative QOL more than replacement of the ascending aorta, and there was lower incidence of postoperative complications due to residual dissection. If Stanford type A aortic dissection extends to the arch, simultaneous replacement of the ascending aorta and the aortic arch is recommended.

Is the Preferential Use of the Fogarty IMAG Kit to Increase ITA Blood Flow Justified? / 日本心臓血管外科学会雑誌

We used the Fogarty 2Fr IMAG Kit^® on 14 patients who underwent aorto-coronary bypass grafting. The free flow of the left internal thoracic artery (LITA) after dilatation using Fogarty balloon catheter was 7.4 times greater than before dilatation. There was no statistical differences in catecholamines used postoperatively and postoperative cardiac output in the groups of cases with and without dilatation. String sign was appeared in 4 patients with dilatation of LITA. Fogarty balloon catheter save effective dilatation of LITA in certain selected cases.

Quantitative Histochemical Analysis of Arterial Grafts Measured by Microspectrophotometry / 日本心臓血管外科学会雑誌

Quantitative histochemical analysis of the internal thoracic artery (ITA) and right gastroepiploic artery (GEA) was performed using microspectrophotometry. Arterial specimens from eight patients who underwent coronary bypass grafting using both ITA and GEA grafts were examined. There were seven men and one woman with a mean age of 60 years; ranging from 36 to 73 years. Concerning risk factors, 4 patients had hypertension, 3 had hypercholesterolemia and 2 had diabetes mellitus. The degree of intimal hyperplasia was calculated as follows; Intimal hyperplasia (%)=(I/I+M)×100 (I: area of intima, M: area of media). Quantitative histochemical analysis (smooth muscle cells, elastin, collagen and mucopolysaccaride) of arterial graft was measured by means of microspectrophotometry. Pieces of both the ITA and GEA grafts were obtained immediately before grafting. Each sample was stained with Azocarmin G, Weigert, van Gieson and Alcian Blue stains to identify smooth muscle cells, elastin, collagen and mucopolysaccaride, respectively. Intimal hyperplasia was significantly greater in GEA than ITA grafts (25.3 ±8.7% versus 6.8±3.5%, respectively; <i>p</i><0.01). In quantitative histochemical analysis of the arterial grafts, the volume of smooth muscle cells was also significantly higher in GEA than ITA at both the intima (ITA; 38.8±7.9%E, GEA; 52.5±7.6%E, <i>p</i><0.01) and media (ITA; 49.6±6. 5%E, GEA; 59.5±8.2%E, <i>p</i><0.05). No significant differences in elastin, collagen or mucopolysaccaride content were observed. The greater amount of smooth muscle in GEA grafts may be one reason why the magnitude of intimal hyperplasia was greater in GEA than ITA grafts. Long-term follow-up is necessary to determine the course of atherosclerotic change in arterial grafts.

Influence of Original or Residual Pseudo-lumen on Perioperative Complications in DeBakey Type Aortic Dissection / 日本心臓血管外科学会雑誌

From April 1990 to December 1993, 13 patients (8 males and 5 females; mean age, 62 years) who underwent surgery for DeBakey type I aortic dissection, were studied to determine pre- and postoperative complications due to original dissection and residual dissection. Ascending aortic replacement had been performed in 9 patients and replacement of the ascending aorta and aortic arch in 4. Preoperative complications were aortic regurgitation (AR) in 3 cases, shock in 4, cardiac tamponade in 5, myocardial ischemia in 2 and spinal cord ischemia in 1. Postoperative complications were visceral and limb ischemia in 1 case, left leg ischemia in 1, spinal ischemia in 2 and worsening AR in 1. The postoperative 30-day survival rate was 85% (11/13). Two patients who underwent urgent ascending aortic replacement with simultaneous coronary artery bypass grafting died within 30 days after surgery. One patient with visceral and limb ischemia died in the hospital. Two patients with spinal ischemia survived but became paraplegic. Cardiac, visceral or spinal ischemia was a common problem in this series. All four patients who underwent ascending aortic replacement with simultaneous aortic arch replacement were alive for 30 days after surgery. The incidence of residual dissection may be reduced by replacing the ascending aorta concomitantly with the aortic arch rather than replacing the ascending aorta only. If a patient with DeBakey type I aortic dissection is in fair preoperative condition and elective surgery is possible, replacement of the ascending aorta and the aortic arch should be considered.

Two Successful Cases of Adult Right-sided Infective Endocarditis with Ventricular Septal Defect / 日本心臓血管外科学会雑誌

Case 1 was a 42-year-old woman who was admitted because of infective endocarditis. Pulmonary embolism occurred during medical treatment for infective endocarditis. Despite the acute infectious phase, surgical treatment was successfully performed. Case 2 was a 50-year-old man who was admitted because of infective endocarditis. Cardiac catheterization showed ventricular septal defect and atrial septal defect. Surgical treatment was performed successfuly. In both cases, and the postoperative courses were unventful.