Keishu Yasuda

Anomalous origin of the left coronary artery from the pulmonary artery in an adult: tubular reconstruction of the left main coronary artery under coronary perfusion.

Abstract A 38‐year‐old female with anomalous origin of the left coronary artery (LCA) from pulmonary artery was surgically corrected by tubular reconstruction of the left main coronary artery (LMCA) using the pulmonary artery wall, and this repair was performed under beating heart. Thus, the pulmonary artery was divided above the orifice level and just above the pulmonary valve, and the commissure between nonfacing and left side sinuses was dissected away from the pulmonary artery wall to obtain lateral flaps. The pulmonary artery defect was reconstructed with a roll using an autologous pericardial patch, while the detached commissure was suspended on the pericardial patch. The long tube constructed using pulmonary artery tissue was anastomosed to the anterior aspect of the ascending aorta. These procedures were performed under beating heart simply by clamping the LMCA, since the preoperative myocardial contrast echocardiography confirmed the adequate coronary collateral flow from the right circulation. The postoperative course was uneventful, and a coronary artery angiogram demonstrated a widely patent LMCA. Our experience suggests that, in adult cases, this procedure could be performed without myocardial ischemia simply by clamping the LMCA because of well‐developed coronary collateral arteries. The safety of this technique could be confirmed by myocardial contrast echocardiography.

Long-term results of aortic valve regurgitation after repair of ruptured sinus of valsalva aneurysm

BACKGROUND We reviewed our 35-year-experience to investigate the determinants of long-term results of aortic valve regurgitation (AR) after surgical repair of ruptured sinus of Valsalva aneurysms (RSVA). METHODS Between 1963 and 1998, a total of 35 patients aged 7 to 64 years underwent surgery for RSVA. The aneurysms ruptured into the right ventricle (n = 24), right atrium (n = 10), and left atrium (n = 1). In all, 19 patients had VSD and 9 patients had AR. A combined approach through aortotomy and the involved chamber was used for 24 patients. Either direct (n = 19) or patch (n = 16) closure was used to close the rupture hole. The AR was graded on a scale of 0 to IV by angiographic or echographic evaluation. RESULTS There were no early deaths. Late death occurred in 1 patient, whose AR deteriorated to grade III 20 years later. Two patients (5.7%) required reoperations on the aortic valve, because grade III AR was noted 8 and 26 years after operation, respectively. Freedom from postoperative grade III AR or higher was 93% at 10 years and was 87% at 20 years. Late AR was associated with preoperative and early postoperative AR (p < 0.05) but not with the presence of VSD, location of the fistula, surgical approach, or type of repair (direct vs patch). Multivariate analysis indicated that early postoperative AR was the only independent variable. CONCLUSIONS Late AR necessitating reoperation still confers significant risk in the long-term follow-up after repair of RSVA. No particular risk factor of preoperative conditions and surgical methods was elucidated in this study, and postoperative AR at discharge from the hospital was the only factor determining the long-term results of AR.

Endothelin receptors, localized in sympathetic nerve terminals of the heart, modulate norepinephrine release and reperfusion arrhythmias

AbstractEndothelin (ET)-1 is an endogenous vasoconstrictor which modulates norepinephrine (NE) release in myocardial ischemia reperfusion. Recent studies have demonstrated the pro- or anti-arrhythmic effects in reperfusion. The present studies were undertaken to test the hypothesis that ET receptors located in sympathetic nerve terminals modulate NE release associated with reperfusion arrhythmias (ventricular fibrillation; VF). Immunohistochemical studies showed that both ETA and ETB receptors exist in the sympathetic nerve varicosities, which were stained positive for tyrosine hydroxylase (TH) in the left ventricular wall in guinea pigs. Isolated guinea pig hearts were subjected to 20 min of normothermic global ischemia followed by 30 min reperfusion. Exogenously applied ET-1 (0.1 and 1 nM) dose-dependently increased NE release and the duration of VF, but these responses were significantly suppressed with the Na+/H+ exchanger inhibitor, 5-(N-ethyl-N-isopropyl)-amiloride (10 μM).The ETA receptor antagonist (BQ123, 1 μM) and nonselective ET receptor antagonist (PD142893, 1 μM) significantly attenuated NE release and VF, whereas the ETB receptor antagonist (BQ788,300 nM) markedly elevated NE release but did not affect VF. These studies provide the first evidence that both ETA and ETB receptors, located in the sympathetic nerve varicosities, modulate NE release, at least in part, in association with reperfusion arrhythmias.

Spinal cord protection during thoracoabdominal aortic aneurysm repair: Results of selective reconstruction of the critical segmental arteries guided by evoked spinal cord potential monitoring

PURPOSE The purpose of this study is to evaluate the results of spinal cord protection based on selective reconstruction of the segmental arteries. METHODS Twenty-one patients who underwent repair of aneurysms (nine descending thoracic and 12 thoracoabdominal: three type I, six type II, and three type III) were analyzed. Ten patients had postdissection aneurysms. Operative techniques consisted of evoked spinal cord potential (ESP-dsc) monitoring and femorofemoral bypass in all cases, segmental resection in 12, and mild systemic hypothermia in eight. Arteries critical for cord blood flow were selectively reconstructed; if ESP-dsc showed change after resection of an aortic segment, arteries originating from this segment were reconstructed. RESULTS ESP-dsc change was observed in 12 patients. Arteries found to be critical were at the T8-L1 level in all but three cases. Selective reconstruction was performed in 10 of these 12 patients. ESP-dsc change could be reversed before reconstruction in four cases, three by control of back-bleeding critical arteries. Selective reconstruction resulted in return of ESP-dsc in seven other patients. Spinal cord injury occurred in five patients, two of whom did not undergo selective reconstruction. CONCLUSION These results suggest that our current technique allows determination of critical arteries but does not completely prevent injury.

Postoperative renal function after elective abdominal aortic aneurysm repair requiring suprarenal aortic cross-clamping.

PurposeTo examine postoperative renal function after suprarenal aortic cross-clamping performed without renal hypothermia in patients undergoing elective abdominal aortic aneurysm (AAA) surgery.MethodsBetween 1991 and 2000, 18 patients underwent surgery for a juxtarenal AAA, which required a suprarenal aortic cross-clamp. All AAAs were repaired with a proximal anastomosis just below the renal arteries. We divided the patients into two groups according to the duration of the renal ischemia: <45 min (n = 12) and ≥45 min (n = 6). The postoperative changes in renal function were analyzed.ResultsThere were no hospital deaths and none of the patients needed permanent hemodialysis. The postoperative peak in the serum creatinine level after suprarenal cross-clamping for ≥45 min was significantly higher than that after cross-clamping for <45 min. The percentage changes in serum creatinine and blood urea nitrogen were correlated positively with the duration of renal ischemia, and were significantly greater in the group with renal ischemia of <45 min than in the group with prolonged renal ischemia (≥45 min).ConclusionsSuprarenal aortic cross-clamp without performing renal hypothermia is safe and able to be tolerated well by the patient during elective AAA surgery, although careful attention must be paid to limiting the period of renal ischemia.

HLA-linked susceptibility gene of Takayasu disease

The HLA-A, B, DR and MB antigens were investigated in patients suffering from Takayasu disease (Aortitis syndrome). Out of twenty-one HLA-A and B antigens tested, only HLA-Bw52 was significantly deviated (30147, PF = 63.8%, RR = 7.8) from the controls (14/76, PF = 18.4%). Since in the Japanese, HLA-Bw52 is in positive linkage disequilibria with HLA-DR2 and MB1, the association of the DR2 and MB1 antigens with Takayasu disease was studied. The HLA-DR2 antigen was significantly increased (23/30, PF = 76.7%,, RR = 6.0) in patients compared with the control (18/51, PF = 35.3%). Moreover, an almost perfect association of MBI (29/30, PF = 96.7%, RR = 12.6) with Takayasu disease was demonstrated. This finding supports the hypothesis that the genes in the HLA-D region play a major role in determining the susceptibility to Takayasu disease.

Current trends in thromboangiitis obliterans (buerger’s disease) in women

BACKGROUND AND PURPOSE Thromboangiitis obliterans (TAO) affects mainly young male smokers and rarely women. Clinical manifestations between men and women with TAO were compared based on the Japanese Nationwide Survey database. PATIENTS AND METHODS From the database registered in 1993, 850 patients with complete records were analyzed. There were 771 males and 79 females, with the mean age of 50.8 +/- 0.4 years. The following factors were compared: Fontaines classification, distribution of lesions, associated disease, response to treatment, and outcome. RESULTS Fontaines classification at the first consultation (P = 0.372) and at the survey (P = 0.740), the incidence of migratory superficial phlebitis (P = 0.76), ulcer formation (P = 0.306), requirement for amputation (P = 0.809) were not different between men and women. Nonsmokers at the first consultation were more common among women (25.3%) than among men (4.9%; P <0.0001). CONCLUSIONS Clinical presentations in women with TAO were almost equal to those in men. The only difference was the higher incidence of nonsmokers in women at the first consultation, but it did not influence the response to treatment or outcome.

Thoracic and cardiovascular surgery in Japan during 1998

of the Survey We sent out survey questionnaire forms to Departments of each category in all 1,004 institutions nationwide in early April 2000. Form sent out and received back by the end of December 2000 Sent out Returned Response rate (A) Cardiovascular surgery 496 457 92.1% (B) Respiratory surgery 654 595 91.0% (C) Esophageal surgery 667 576 86.4% Categories subclassified according to the number of operations performed

Current status of thromboangiitis obliterans (Buerger’s disease) in Japan

We analysed clinical features and outcome in 850 patients with thromboangiitis obliterans (TAO), based on the 1993 Nationwide Survey of Vasculitis database collected from 3722 clinical sites in Japan. The survey was designed to assess clinical manifestation categorized by Fontaines classification, distribution of lesions (arterial involvement and migratory superficial phlebitis), response to medical and surgical treatment, and outcome. There were 771 males (90.7%) and 79 females (9.3%), with a mean age of 50.8+/-0.4 (range: 17-81) years. Clinical manifestations at the first consultation were Fontaine I in 8.0%, Fontaine II in 29.6%, Fontaine III in 23.9%, and Fontaine IV in 38.1%. These symptoms had been significantly improved by the time of survey. Ulcer formation in the past history had occurred in 45.2%, which was the most common in toes (85.9%). Failure of smoking cessation significantly affected the risk of ulcer formation (odds ratio=1.71, 95% CI=1.19-2.47; P=0.004) and amputation (odds ratio=2.73, 95% CI=1.86-4.01; P<0.0001). Clinical features in female patients with TAO were equal to those in male patients, except for the fact that non-smokers were more common in female patients. Abstinence from tobacco significantly reduces the risk of ulcer formation and amputation, and thus improves the quality of life in patients with TAO.

Use of bioresorbable membrane to prevent postoperative small bowel obstruction in transabdominal aortic aneurysm surgery.

PurposeTo evaluate the efficacy of Seprafilm (Genzyme, Cambridge, MA, USA), a bioresorbable membrane, in preventing or reducing early postoperative small bowel obstructions after transabdominal abdominal aortic aneurysm (AAA) surgery.MethodsFifty-one patients underwent aortic reconstruction via a midline transperitoneal approach for infrarenal AAAs. Twenty-one patients underwent surgery with Seprafilm (Seprafilm group) and the remaining 30 patients did not (control group). The incidence of early small bowel obstruction was examined, and the time before liquid and solid diet were resumed was also compared to assess postoperative paralytic ileus.ResultsPatients in the Seprafilm group resumed a liquid diet on postoperative day (POD) 2.4 ± 1.1 and a solid diet on POD 4.0 ± 1.3, whereas the patients in the control group resumed a liquid diet on POD 3.3 ± 1.9 and a solid diet on POD 5.4 ± 3.4. These values were not significantly different between the two groups; however, the incidence of early postoperative small bowel obstruction was significantly lower (P < 0.05) in the Seprafilm group (0/21) than in the control group (6/30).ConclusionThese findings suggest that Seprafilm may help to prevent early postoperative small bowel obstructions after transabdominal AAA surgery.