Right Parasternal Vertical Approach for Tricuspid Valve Replacement in Repeated Cardiac Surgery / 日本心臓血管外科学会雑誌

Median sternotomy is the most common approach used for repeated cardiac surgery, but it is associated with potential risks such as cardiac injury. Patients with valvular heart disease may be especially prone to these complications because of severe cardiomegaly and adherence of the heart to the posterior sternum. To avoid these risks, we began using a right thoracotomy approach, performed through a right parasternal vertical incision, which is better than the traditional right anterolateral thoracotomy, in selected patients. A 50-year-old woman who had undergone 3 previous cardiac operations at another hospital presented with remarkable cardiomegaly. We performed successful tricuspid valve replacement for tricuspid stenosis, through a right parasternal vertical incision. This approach provides excellent exposure of the tricuspid valve with minimal need for dissection. The right parasternal vertical incision has 3 main advantages over right anterolateral thoracotomy; first, it provides an excellent view of the right atrium underneath the wound; second, it allows for easy cannulation because of the position of the spine; and third, the skin incision is smaller. In conclusion, we think that the parasternal vertical incision is a better approach for repeated cardiac surgery than anterolateral thoracotomy because it provides a better operative view and an easier maneuver.

Bifurcated Endovascular Graft for Abdominal Aortic Aneurysm Repair: A Multi-Center Trial of the PowerWeb System / 日本心臓血管外科学会雑誌

Infra-renal abdominal aortic aneurysms were electively treated by bifurcated endovascular stent grafts (Power Web^TM system, Endologix Co., USA) at 5 Japanese centers. The stent grafting (SG) was applied for candidates nominated by the selection committee after informed consent was obtained according to the IRB in each center. The delivery success rate of 60 patients (53 males) was 96.7%. There were 2 patients with type I endoleaks, resulting in a technical success rate of 93.3%. The operation time of 193±55min and blood loss of 440±240g were significantly shorter and less, respectively in the SG group when compared with 303±88min and 1, 496±2, 025g in 97 patients (83 males) treated by conventional open surgery. Endoleaks were detected in 4 patients (type I: 3, type II: 1) by CT scan taken at the time of discharge or 1 month after SG procedure. Type I endoleak was observed in patients with short and severely angulated SG landing zones. Renal artery obstruction, and temporary buttock pain caused by internal iliac artery occlusion occurred, but there was no hospital death. In 56 patients excluding an SG-unrelated death and a dropout from surveillance, there was no secondary endoleak or marked adverse events at all except 1 SG limb occlusion during a 6-month follow up period. The aneurysm size shrank in 26 patients and remained unchanged in 30 patients. No aneurysm enlargement was observed. The Power Web^TM system is appropriate for minimally invasive surgery for abdominal aortic aneurysms. Long-term follow-up studies will follow.

Role of Neutrophils in Ischemia/Reperfusion Injury during Heart Surgery / 日本心臓血管外科学会雑誌

To test the hypothesis that neutrophils play a role in ischemia/reperfusion injury during heart surgery, granulocyte elastase and myeloperoxidase release from coronary circulation were measured before and after aortic cross-clamping. The production of granulocyte elastase and myeloperoxidase across the coronary circulation elevated significantly after release of aortic cross-clamp. Furthermore, the level of granulocyte elastase and myeloperoxidase released from coronary circulation demonstrated positive correlation with the duration of the aortic cross-clamp. These data indicate that neutrophils play a major role in ischemia/reperfusion injury occurring during heart surgery.

Role of Neutrophils in Pulmonary Dysfunction during Cardiopulmonary Bypass / 日本心臓血管外科学会雑誌

To test the hypothesis that neutrophils play a role in lung injury during cardiopulmonary bypass, granulocyte elastase and myeloperoxidase release from pulmonary circulation were measured, as well as the respiratory index, before and after cardiopulmonary bypass. The production of granulocyte elastase and myeloperoxidase in the pulmonary circulation, and the respiratory index also elevated significantly after cardiopulmonary bypass. Furthermore, the level of granulocyte elastase and myeloperoxidase released from pulmonary circulation correlated with the changes of the respiratory index and preoperative pulmonary artery pressure. These data indicate that neutrophils play a major role in pulmonary dysfunction occurring after cardiopulmonary bypass, which is accentuated in patients with pulmonary hypertension.

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.

Effects of Intermittent Tepid Blood Cardioplegia in Coronary Artery Bypass Grafting / 日本心臓血管外科学会雑誌

A total of 56 patients undergoing coronary artery bypass grafting were allocated to two groups: the Cold group (28 patients) with cold (4°C) crystalloid cardioplegia and topical ice slush, and the Tepid group (28 patients) with tepid (32°C) blood cardioplegia delivered intermittently antegrade. The two groups were comparable in terms of preoperative New York Heart Association classification, age, gender, and number of grafts. Intraoperatively, tepid blood cardioplegia was associated with a significantly shorter cardiopulmonary bypass time and nearly uniform return of normal sinus rhythm. Cardiac output after bypass was significantly higher than before bypass only in the Tepid group. The absolute peak levels in the myocardial-specific isoenzyme of creatine kinase were higher in the Cold group (70±8IU/<i>l</i>) than in the Tepid group (31±5IU/<i>l</i>). There was a trend toward reduced incidence of perioperative myocardial infarction (0% versus 7.1%) and need for intraaortic balloon pump support (0% versus 3.6%) associated with the use of tepid blood cardioplegia. Our results suggest that intermittent tepid blood cardioplegia is a safe and effective technique for coronary artery bypass grafting.

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.

A Case of Aberrant Right Subclavian Artery Aneurysm and a Review of the Literature / 日本心臓血管外科学会雑誌

Aberrant right subclavian artery is a common congenital anomaly of the aortic arch, with a reported prevalence of approximately 0.5%. However aneurysms of this aberrant vessel are very rare. A 71-year-old man was admitted with cerebral hemorrhage. Chest X-ray revealed an abnormal upper mediastinal shadow. Angiography, computed tomography (CT) scan, and magnetic resonance (MR) imaging revealed an aberrant origin of the right subclavian artery arising as the fourth branch of the aortic arch and crossing the mediastinum from left to right indenting the esophagus posteriorly. The origin of the right subclavian artery was aneurysmal (maximum diameter was 5cm), and this aneurysm did not compress the esophagus. The patient was treated by Dacron patch graft aortoplasty and right subclavian artery reconstruction with the aid of cardiopulmonary bypass and hypothermic selective cerebral perfusion. The postoperative course was uneventful and there were no major complications. The surgical technique is detailed as well as a review of all the cases in the literature.

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.

Quality of Life after Thoracic or Thoraco-Abdominal Aneurysmectomy / 日本心臓血管外科学会雑誌

We investigated the quality of life (QOL) after thoracic or thoraco-abdominal aneurysmectomy in patients who had undergone the procedure within the past 15 years. We compared preoperative to postoperative performance status (PS). Defining PS in the following manner: one increase in that PS grade indicated mild worsening while an increase is by 2 or more indicated severe worsening. Maintenance was indicated by no change of PS after surgery. The QOL maintenance rate was calculated based on the following formula.<br>QOL maintenance(%)=No. of no change case/No. of operated cases-No. of death×100<br>There were a total of 74 cases in whom follow-ups could be carried out after surgery. Among them, there were ascending and aortic arch aneurysms in 19 cases, descending aortic aneurysms in 20 cases, dissecting aneurysms in 27 cases and thoraco-abdominal aortic aneurysms in 8 cases. The QOL maintenance rate in the type B dissecting aneurysms was comparatively high (85.7%). There were cases of severe worsening of PS in the ascending and aortic arch aneurysms and type A dissecting aneurysms and the QOL maintenance rate was 50% in each other. We should obtain high operative results due to improve the QOL maintenance rate, and devise the operative procedure without functional disorders of the organs after surgery.

A Case of Chronic Contained Rupture of Infrarenal Abdominal Aortic Aneurysm / 日本心臓血管外科学会雑誌

A chronic contained rupture of an infrarenal abdominal aortic aneurysm eroded a lumbar vertebra. A 53-year-old man complained of severe back pain for 6 months. Recently the back pain had increased. The patient looked well but a pulsatile mass in the abdomen was palpable. A CT and MRI of the abdomen and lumbar spine revealed the infrarenal abdominal aneurysm which demonstrated destruction of the third and fourth lumbar vertebra. At operation, there was a true aneurysm of the native aorta with a rupture of the posterior wall, resulting in a retroperitoneal hematoma. An orifice of the ruptured pseudoaneurysma was 2×2cm in size. An aortobiiliac graft was implanted. The patient did well postoperatively and was discharged on the 32nd postoperative day.

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.

Relationship between Graft Flow and Patency in Patients Undergoing Femoro-Popliteal Bypass Operation / 日本心臓血管外科学会雑誌

Preoperative and operative evaluation of the arterial reconstructive tract is very important to obtain a high reconstructed graft patency rate after femoro-popliteal bypass. We analyzed the graft patency rate of 40 cases in which the graft flow was measured immediately after completion of arterial reconstruction. The mean graft flow was 122.6ml/min in patients with above-knee (AK) reconstruction and 57.4ml/min in those with below-knee (BK) reconstruction. In cases with AK reconstruction, the three-year cumulative patency rates of grafts with a blood flow of 120ml/min or more (<i>n</i>=12) or less than 120ml/min (<i>n</i>=11) were 100% and 80.8%, respectively (<i>p</i><0.05). In cases with BK reconstruction, the three-year cumulative patency rates of grafts with a blood flow of 55ml/min or more (<i>n</i>=9) and less than 55ml/min (<i>n</i>=8) were 62.2% and 50.0%, respectively. All early occlusions (<i>n</i>=5) occurred in patients with BK reconstructions. Despite having a blood flow greater than 55ml/min, two cases became occluded in the early stage due to knee joint bending. It is considered that intraoperative measurement of the graft flow is one index to predict graft patency.

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.

Changes of Hemodynamic and Blood Chemical Mediators after Aortic Clamping in Infrarenal Abdominal Aortic Aneurysmectomy / 日本心臓血管外科学会雑誌

Changes of hemodynamics and chemical mediators before and after aortic clamping were investigated in 12 patients who underwent infrarenal abdominal aortic aneurysmectomy. Patients were divided into two groups; one with an aortic clamping time greater than 1 hour (the long group) and the other with aortic clamping time less than 1 hour (the short group). Cardiac output, mean pulmonary arterial pressure (MPAP), extravascular thermal volume (ETV), polymorphonuclear elastase (PMN-E), α₁ trypsin inhibitor (α₁-TI) superoxide dismutase (SOD), urine <i>N</i>-acetyl-β-D-glucosaminidase (NAG), were measured before and immediately after aortic clamping, immediately after, 1 and 4 hours after aortic declamping. In addition, serum GOT, GPT, creatinine and BUN were measured before and 1, 3 and 7 day after operation. These levels were expressed as ratios of the level before aortic clamping and operation. The MPAP ratio immediately after aortic clamping was 0.83±0.06 in the long group and 0.99±0.08 in the short group. There was statistical significant difference in the MPAP between both groups (<i>p</i><0.01). In contrast, there was no significant difference in the cardiac output or ETV between the two groups. The PMN-E ratio immediately after aortic declamping was 2.24±0.81 in the long group and 1.19±0.45 in the short group. These ratios increased at 1 and 4 hours after aortic declamping. The PMN-E ratio following aortic clamping in the long group was greater than those in the short group (<i>p</i><0.05). The SOD at 1 hour after aortic declamping was 0.78±0.13 in the long group and 1.01±0.11 in the short group (<i>p</i><0.05). The NAG ratio immediately and at 1 hour after aortic declamping was significantly higher in the long group when compared with the short group (<i>p</i><0.01, 0.1). Serum GOT, GPT, creatinine and BUN ratios showed no change through out this study. There was an increase in protease and a decrease of free radical scavengers in the long group. These findings are commonly known to be linked with organ damage. Through the findings of this study, we suggest that clamping time should be minimized; thus reducing the possible chance of postoperative organ damage.

Mitral Valve Aneurysm Complicated with Aortic Regurgitation Due to Infective Endcarditis / 日本心臓血管外科学会雑誌

A 47-year-old male complaining of dyspnea and fever was admitted to our hospital and regurgitation of the aortic and mitral valves with mitral valve aneurysm due to infective endcarditis was diagnosed. The non-coronary and the right coronary cusps of the aortic valve had amount of vegetations, and also the anterior leaflet of the mitral valve had an aneurysm with vegetations. Both aortic and mitral valve replacement were performed. The postoperative clinical course was uneventful.

A Case of Descending Aortic Aneurysm Associated with Coarctation of the Aorta / 日本心臓血管外科学会雑誌

It is known that the prognosis of preductal type coarctation of the aorta is poor because cardiac malformation is frequent in these cases. There have been very few reports on adult cases of the coarctation. We have recently carried out aneurysmectomy and reconstructed the descending aorta by a 30mm Veri-Soft tube graft for one adult case of descending aortic aneurysm associated with coarctation of the aorta. The patient was 49-year-old female. Segmental stenosis 5cm in length was demonstrated in the thoracic descending aorta immediately below the bifurcation of the left subclavian artery. The poststenotic dilatation was shown at the distal portion of the segmental stenosis. The postoperative clinical course was uneventful.