R Sakata

University of Ryukyus, Okinawa, Okinawa-ken, Japan

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Publications (41)93.22 Total impact

  • Article: Coronary artery bypass grafting for dialysis patients. Effects of cardiopulmonary bypass.
    Y Nakayama, R Sakata, M Ura
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    ABSTRACT: To assess the efficacy and safety of cardiopulmonary bypass during coronary artery bypass grafting (CABG) in dialysis patients. Sixty four isolated CABG patients who underwent on cardiopulmonary bypass and whose intraoperative body weight gains were accurately measured were studied retrospectively. The mean intraoperative body weight gain was 2.61 +/- 0.9 kg/m2 in the study group and 1.06 +/- 0.6 kg/m2 in controls, i.e.) 100 patients selected at random from CABG patients during the same period using cardiopulmonary bypass without chronic renal faulure, showing a statistically significant difference. Complete revascularization was successful in 98% of patients. Postoperative nonlethal complications involved brain infarction in 1 patient (1.7%), reintubation in 1 (1.7%), and paralytic ileus in 2 (3.4%). All were successfully extubated within 24 hours of surgery, and no sternal wound complications were found. Hospital mortality was 6.3% (4/64). Actuarial survival rates at 3, 5 and 8 years including all deaths were 90%, 70% and 56%, and estimated by cardiac deaths were 95%, 90%, and 90% respectively. Cardiac event free rates were 90%, 73% and 61% at 3, 5 and 8 years after CABG. In CABG for dialysis patients, the use of cardiopulmonary bypass demonstrates significant merits, and may expect long-term survival with minimal postoperative complications.
    The Japanese Journal of Thoracic and Cardiovascular Surgery 09/2001; 49(8):504-8.
  • Article: Early results and characteristic problems associated with cardiac surgery in long-term dialysis patients.
    Y Nakayama, R Sakata, M Ura
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    ABSTRACT: To analyze early results and characteristic problems that develop after cardiac surgery on dialysis patients. One hundred fourteen patients on maintenance dialysis underwent cardiac surgery. Their mean age was 63.5 +/- 9.7 years, and 87 (76%) were male. The causes of chronic renal failure were diabetes mellitus in 41 (36%) and chronic glomerulonephritis in 40 (35%). Patients had previously been on dialysis for a mean duration of 7.8 +/- 5.6 years (range; 0.25-24 years). Fourteen (12%) were emergent cases. Eighty six patients (75%) received isolated coronary artery bypass grafting (CABG), and 10 patients underwent operations in which CABG was combined with other cardiac procedures. Twelve patients (14%) of the isolated CABG patient group (86 patients) were restricted to non-clamping bypass procedure due to severe calcification of the ascending aorta. Calcification score, which was represented by the sum of all involved coronary artery segments, was also significantly higher in dialysis patients than in the control group (4.5 +/- 2.4 segments vs. 1.5 +/- 2.1 segments, p < 0.05). Hospital mortality was 8.8% (10/114) overall, and 7% (6/86) in isolated CABG patients. The causes of deaths were as follows: intestinal necrosis in 3, arrhythmia in 2, cerebral infarction in 1, low output syndrome in 1, and sepsis in 3 (mediastinitis, pneumonia, and prosthetic valve infection). Long-term dialysis is a major risk factor in cardiac surgery. However, because the surgical results proved to be acceptable, long-term dialysis patients should not be denied cardiac surgery.
    The Japanese Journal of Thoracic and Cardiovascular Surgery 08/2001; 49(7):420-3.
  • Article: Technical aspects and outcome of in situ right internal thoracic artery grafting to the major branches of the circumflex artery via the transverse sinus.
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    ABSTRACT: Little is known about the anatomic limitations of in situ right internal thoracic artery (RITA) grafting to the circumflex artery. To evaluate the technical aspects and outcome of revascularization of the proximal and distal major branches of the circumflex artery (obtuse marginal [OM] branch and posterolateral [PL] branch), a total of 145 patients who possessed a graftable branch of the circumflex artery were enrolled into the prospective project. There were 73 patients who had the PL branch as a primary target and 72 patients with OM branches, which were allocated by a blinded observer who reviewed the preoperative angiography. Changes of primary target vessels were required in 9 patients (6.2%), yielding an overall success rate of RITA grafting of 93.8%. The success rates of RITA grafting to the OM branch and the PL branch were 95.8% (69/72; CI 88.3% to 99.1%) and 91.7% (67/73; CI 83.0% to 96.9%), respectively. The univariate analysis identified grafting under hypothermic ventricular fibrillation as predictors of inability to use in situ RITA grafting for revascularization of the circumflex artery. RITA grafting to the PL branch is not identified as a predictor. Postoperative angiography in 136 patients revealed only one occlusion (0.75%) of the RITA graft anastomosed to the marginal artery. There were no significant differences in patency rates between left and right ITA grafts. This prospective study showed that in situ RITA was, in most cases, able to reach most branches of the major circumflex artery and demonstrated an excellent patency rate.
    The Annals of Thoracic Surgery 06/2001; 71(5):1485-90. · 3.74 Impact Factor
  • Article: Coronary artery bypass grafting for dialysis patients: usefulness of multiarterial bypass.
    Y Nakayama, R Sakata, M Ura
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    ABSTRACT: This study assessed the efficacy of multiarterial bypass in coronary artery bypass grafting (CABG) in dialysis patients. Eighty dialysis patients who underwent CABG were divided into 2 groups. Group A consisted of 38 patients in whom the left internal thoracic artery and additional saphenous vein graft (SVG) had been used. Group B consisted of 42 patients in whom 2 or 3 arterial grafts and additional SVGs had been used. No mediastinitis was shown in either group. Actuarial survival rates, including all deaths, and estimated by cardiac deaths at 8 years, were 28% and 83%, respectively, in Group A and 93% and 100%, respectively, in Group B with a significant difference (p = 0.014 and 0.016, respectively). Cardiac event-free rates at 8 years were 43% and 96% in Groups A and B, respectively, with a significant difference (p = 0.0016). Multiarterial grafting improved long-term results after CABG for dialysis patients compared with single internal thoracic artery grafting with minimal complications related to graft harvesting.
    Artificial Organs 05/2001; 25(4):248-51. · 2.00 Impact Factor
  • Article: One-stage thoracic aortic aneurysm treatment and coronary artery bypass grafting.
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    ABSTRACT: The treatment of thoracic aortic aneurysm accompanied by ischemic heart disease presents a surgical challenge and has up to now shown a high hospital mortality rate. This report discusses the factors contributing to improved results in these cases. We conducted a retrospective analysis of the records of 24 consecutive patients who had undergone replacement of thoracic aorta with combined coronary artery bypass grafting (CABG) between May 1991 and October 1998. Fifteen patients received total arch replacement (Arch-with-CABG Group), and the other 9 patients received the Bentall operation (Bentall-with-CABG Group). These results were compared with those patients who had undergone replacement of the thoracic aorta without CABG (Without-CABG Group). In the combined CABG groups, the overall operative mortality rate was 16.7%. In comparison with the Arch-without-CABG Group, there was a significantly longer cardiopulmonary bypass time and longer selective cerebral perfusion time in the Arch-with-CABG Group. However, no significant difference was observed in postoperative complications between the two groups. In addition, there was no significant difference in either actuarial survival or the cardiac-event-free rate at 5 years between the replacement of thoracic aorta with- and without-CABG Groups (83.1% vs. 90.4%, and 78.5% vs. 77.7%, respectively). No reoperation and no late death were observed during the follow-up period (mean 21.3 months). We concluded that replacement of the thoracic aorta combined with CABG can be carried out safely, and that revascularization for coronary artery disease is useful for preventing any occurrence of cardiac event.
    The Japanese Journal of Thoracic and Cardiovascular Surgery 05/2001; 49(4):236-43.
  • Article: Bilateral internal thoracic artery use for dialysis patients: does it increase operative risk?
    Y Nakayama, R Sakata, M Ura
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    ABSTRACT: The efficacy and risk of using the bilateral internal thoracic artery (BITA) for coronary artery bypass grafting in dialysis patients is virtually unknown. Twenty-five patients on dialysis who underwent coronary artery bypass grafting using the BITA were retrospectively studied (BITA group). For comparison purposes, 52 patients on dialysis who underwent coronary artery bypass grafting using the left ITA were selected (LITA group). No wound healing problems occurred in the BITA group. Mean postoperative bleeding volume was 1,427 +/- 808 mL and 800 +/- 508 mL in the BITA and LITA groups, respectively (p = 0.00009). Blood transfusions for the BITA and LITA groups required an average of 6.8 and 6.2 units of packed red blood cells, respectively, with no significant difference. Five patients in the BITA group (20%) showed severe atherosclerotic deterioration of the ascending aorta, precluding clamping. Hospital mortality was 4% (1 of 25 patients) in the BITA group and 7.7% (4 of 52 patients) in the LITA group, with no significant difference (p = 0.49). In patients on dialysis, especially those with severe atherosclerotic or calcified deterioration of the ascending aorta, coronary artery bypass grafting using BITA grafting (arterial in situ conduits) may offer the easiest and most suitable solution without increased operative risk.
    The Annals of Thoracic Surgery 04/2001; 71(3):783-7. · 3.74 Impact Factor
  • Article: The impact of chronic renal failure on atherosclerosis of the internal thoracic arteries.
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    ABSTRACT: Little is known about the impact of renal failure on atherosclerotic changes in the internal thoracic artery (ITA). A total of 20 consecutive patients on chronic dialysis who underwent coronary artery bypass grafting (CABG) during April 1998 through September 1999 were investigated. The 20 control patients were selected from the same interval to rigorously match risk factors. Atherosclerosis of the ITA collected from each patient was analyzed using the subjective evaluation proposed by Kay and colleagues. There were no cases of greater than 25% atherosclerotic luminal narrowing among a total of 35 ITA specimens from dialysis patients. The degree of atherosclerosis was not significantly different from that of the specimens from matched patients (p = 0.18). No calcification was found in ITA grafts either microscopically or macroscopically. The number of elastic lamellae, an index of the elasticity of the ITA graft, was not significantly different from those obtained from the matched patients. Analysis of preoperative coronary angiography revealed that coronary calcification was significantly more frequent in dialysis patients (15 patients, 75%) than in matched patients (p < 0.05). By analysis of postoperative angiography in dialysis patients, no evidence of atherosclerotic changes was found in 28 opacified ITAs. In addition, despite the presence of calcification in the native coronary, no calcification was evident along the entire length of the ITAs. This study revealed the minimal impact of chronic renal failure on atherosclerotic changes in the ITA. The results of this study support the continued use of ITA grafting in dialysis patients.
    The Annals of Thoracic Surgery 02/2001; 71(1):148-51. · 3.74 Impact Factor
  • Article: Growth potential of left internal thoracic artery grafts: analysis of angiographic findings.
    Y Nakayama, R Sakata, M Ura
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    ABSTRACT: The growth potential of the internal thoracic artery (ITA) is still undetermined, and little is known about the long-term effects of anastomosing it to the coronary artery. Fifty-three patients whose left ITA (LITA) had been anastomosed to the left anterior descending (LAD) coronary artery underwent coronary angiography within 1 month of operation and in late follow-up (mean interval: 4.5 +/- 1.5 years). The diameter ratios of LITA to LAD were designated as the matching ratio. In follow-up, the diameter of the LITA increased from 1.83 +/- 0.40 to 2.46 +/- 0.53 mm in the 29 patients with progressive proximal native coronary stenosis. However, late results indicate that the matching ratio did not vary according to the location of the LITA anastomosis on the LAD (proximal portion: 1.13 +/- 0.16, distal portion 1.19 +/- 0.13), and reached an upper limit of about 1.4. Growth potential of the LITA is limited by the diameter of the coronary artery onto which it is anastomosed. The most effective procedure for enhancing the growth potential of the LITA is to anastomose as proximally as possible onto the LAD.
    The Annals of Thoracic Surgery 02/2001; 71(1):142-7. · 3.74 Impact Factor
  • Article: Long-term angiographic evaluation of free internal thoracic artery grafting for myocardial revascularization.
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    ABSTRACT: Between 1990 and 1998, 41 patients underwent free internal thoracic artery grafting for coronary artery bypass. To investigate usefulness of free internal thoracic artery grafting, we compared the postoperative graft patency of free internal thoracic artery grafts with that of in situ internal thoracic artery grafts, and compared the long-term results such as actual survival and cardiac-event free rate in patients receiving free internal thoracic artery grafts with those results in patients receiving in situ internal thoracic artery grafts. Postoperative changes in luminal diameter of free internal thoracic artery grafts were calculated as the difference between the first and secondary angiographic evaluation in 17 patients who were followed-up for more than 5 years. The early postoperative graft patency rate of free internal thoracic artery was 95.2%. All these early patent grafts remained patent at the time of the late study. At 9 years post-surgery, patients who received free internal thoracic artery grafts had a survival rate of 100% and a cardiac event-free rate of 77.5%; the luminal diameter enlargement was 0.57 mm, and the mean matching rate increased 27.8%. We conclude that the free internal thoracic artery provides long-term results comparable with those of in situ internal thoracic artery.
    Annals of thoracic and cardiovascular surgery: official journal of the Association of Thoracic and Cardiovascular Surgeons of Asia 01/2001; 6(6):378-82. · 0.69 Impact Factor
  • Article: Long-term results of bilateral internal thoracic artery grafting.
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    ABSTRACT: Little is known about the long-term results of the uniform group of patients who had bilateral internal thoracic artery (ITA) grafting with the method of left ITA-to-left anterior descending coronary artery and right ITA-to-circumflex artery. Late follow-up study was performed in the first consecutive 203 patients (mean age, 62.6 +/- 9.1 years) who underwent isolated coronary artery bypass grafting with the left ITA anastomosed to the left anterior descending coronary artery and the right ITA to major branches of the circumflex artery. The patients were grouped according to the patency of ITA grafts demonstrated by early postoperative angiography (Both patent (BP) group, 168 patients: both ITAs showed complete patency; Not patent (NP) group, 23 patients: at least one ITA was dysfunctional). Actuarial 7-year survival in all patients was 89.3% +/- 3.1%. The cumulative probability of event-free survival for cardiac death, myocardial infarction, intervention, and angina at 7 years was 96.6% +/- 1.8%, 98.0% +/- 1.5%, 86.7% +/- 3.2%, and 90.7% +/- 2.9%, respectively. NP group had more myocardial infarction and angina than the BP group, but was not statistically significant. Because of failed grafts at the early angiography, intervention was performed more frequently in NP group (p < 0.01). Our results of actuarial 7-year survival and the cumulative probability of event-free survival were at least comparable to the results of other similar studies using bilateral ITA. The freedom from angina appeared to be better than in the previous study. Overall our study supports the continued use of this method of ITA grafting.
    The Annals of Thoracic Surgery 12/2000; 70(6):1991-6. · 3.74 Impact Factor
  • Article: Complete revascularization of the left anterior descending coronary artery.
    Y Nakayama, R Sakata, M Ura, Y Arai
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    ABSTRACT: To assess the efficacy of complete revascularization of the left anterior descending coronary artery. To obtain such revascularization, 81 patients required the use of such complex techniques as the onlay patch technique or double bypasses during bypass grafting. The onlay patch technique was used in 39 (48%) and double bypasses in 42 (52%). The wall motion in all anterior segments of the left ventricle showed an improving trend postoperatively. The patency rate was 99% overall, and the bypass grafts to the left anterior descending coronary artery were all patent with flow in all left anterior descending coronary artery areas. Perioperative myocardial infarction occurred in only 1 patient (1.2%), and hospital mortality was 2.5% (2/81). Long-term results of 79 hospital survivors were as follows: the mean follow-up time was 77 months (3 to 236); the actuarial survival rate including all deaths and estimated by cardiac death was 90% and 95% at the eighth postoperative year respectively; the cardiac event free rate at the fifth and eighth postoperative year was 90% and 63% respectively. A total of 8 cardiac events were observed. Excluding 3 cardiac deaths, no cardiac events were clearly attributable to the left anterior descending coronary artery. Complete revascularization of the left anterior descending coronary artery using these techniques improved the anterior wall motion in the left ventricle and cardiac performance at low risk, and provided excellent long-term results.
    The Japanese Journal of Thoracic and Cardiovascular Surgery 12/2000; 48(11):717-24.
  • Article: [Surgical results of valvular heart disease combined with myocardial revascularization].
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    ABSTRACT: Risk factors for hospital death after combined valvular and coronary artery bypass surgery were examined in 131 consecutive cases between October 1988 and December 1999. These accounted for 8.0% of all 1,644 cases of coronary revascularization surgery and 15.3% of all 854 cases of valvular heart disease surgery. 84 men and 43 women underwent combined valvular and coronary artery bypass surgery. The mean age of the patients was 68.9 +/- 3.9 (22-86) years old. Numbers of cases comprised 58 undergoing aortic valve surgery, 63 undergoing mitral valve surgery, and 10 undergoing eight patients died during hospitalization after the operation: four due to cardiac death and four due to non-cardiac death. We studied pre- and perioperative risk factors for hospital death by means of multivariate analysis. As the major factors, ischemic mitral regurgitation, chronic renal failure, and duration of cardiopulmonary bypass were identified as three major predictors of hospital death. Ischemic mitral regurgitation was the strong predictor (p = 0.03) with 5 hospital deaths out of 38 ischemic mitral regurgitation cases (13.1%), whereas only 3 hospital deaths were seen in 93 other cases (3.2%) operated on in the same period. Over all operation results were not unfavorable, indicating that combined operations may be electively performed if severe coronary artery disease was present. The surgical results with ischemic mitral regurgitation are as yet not well documented and will require further study.
    Kyobu geka. The Japanese journal of thoracic surgery 08/2000; 53(8 Suppl):644-9.
  • Article: Long-term results of root reconstruction using the Carrel patch.
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    ABSTRACT: The treatment of annuloaortic ectasia in patients, including those with Marfan syndrome, ascending aortic dissection, and other disorders of the ascending aorta and aortic valve presents a surgical challenge that has, unfortunately, shown high hospital mortality up to now. Improvements in graft materials and advanced surgical techniques have, however, begun to reduce hospital mortality. We retrospectively analyzed the records of 47 consecutive patients who undergoing aortic root reconstruction using the Carrel patch between January 1991 and March 1999. Postoperative complications included myonephrotic metabolic syndrome caused by femoral artery cannulation in 2 patients. Reexploration was done to halt bleeding in 2 patients. In 1 of 4 acute dissection patients, retrograde filling of the false lumen was demonstrated postoperatively. Overall surgical mortality in this series was 2.1% (1 of 47). The cardiac-event free rate was 98% at 5 years and 88% at 8 years. Actual survival is 97.8% at 8 years. No anastomosis complications were seen during follow-up (average: 32.7 months) (about 2.73 years). Surgery is considered feasible in any anatomic variation of aortic root disease, even in coronary ostial minimal dislocation, and the Carrel patch holds hope in preventing of anastomotic pseudaneurysm and ensuring long-term survival. Our experience suggests that modified Bentall operation, or aortic root remodeling using the Carrel patch, has few late-term complications, even in Marfan patients.
    The Japanese Journal of Thoracic and Cardiovascular Surgery 06/2000; 48(5):267-73.
  • Article: Echocardiographic and pathological evaluation of atherosclerosis in the ascending aorta during coronary artery bypass grafting.
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    ABSTRACT: We performed intraoperative echocardiography with an epiaortic probe to assess the correlation between echocardiographic appearance and pathological findings of the aorta and to examine the effect of cross-clamping on the aortic wall in 276 patients who underwent coronary artery bypass grafting. The ascending aorta was divided into three segments as follows: lower (L), upper (U), and innominate. The anterior (ant) and posterior (post) intimal thicknesses of each of the three segments were measured. The echogenicity at each of the six locations was examined and was classified as isoechoic or nonisoechoic (hyperechoic, hypoechoic, or mixed type). Tissue punched from the ant L wall of the ascending aorta for vein anastomosis was examined for the presence of atheroma. At the ant L, the prevalence of atheroma was significantly higher in nonisoechoic walls than in isoechoic walls (P = 0.049). We divided patients into two groups according to echogenicity at the U segments. Group A (n = 213) consisted of patients whose echogenicities at both ant U and post U were isoechoic. Group B (n = 63) consisted of patients with nonisoechoic echogenicity at ant U and/or post U. The intimal thicknesses at all six locations in Group B patients were greater than those of Group A (P < 0.01). Deformities at the clamp site after cardiopulmonary bypass were observed significantly more often in Group B than in Group A (P < 0.01). Our data suggest that a nonisoechoic aortic wall indicates more advanced atheroma and a higher risk of deformities at the clamp site. Examination of the echogenicity of the ascending aorta may be one method to reduce perioperative neurological complications. Implications: We performed epiaortic echocardiography during coronary artery bypass grafting and found that the presence of atheroma and deformities at the cross-clamping site were significantly more prevalent in nonisoechoic walls than isoechoic walls.
    Anesthesia & Analgesia 06/2000; 90(6):1262-8. · 3.29 Impact Factor
  • Article: Cardiac operations in patients with severe pulmonary impairment.
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    ABSTRACT: Many reviews concerning pulmonary complications after cardiac surgical procedures in patients with serious pulmonary disease have been published. However, no strict pulmonary function guidelines were proposed to help the clinician identify the patients at greater risk. We considered whether a low pulmonary function became a risk factor of cardiac operations. We conducted a retrospective analysis of records of 32 patients with severely impaired preoperative pulmonary function who had undergone cardiac operations between July 1988 and March 1999. There was 1 hospital death. The over-all mortality rate was 3.1% (1 of 32). However, this death could not be directly attributed to postoperative pulmonary complications. Postoperative pulmonary complications were seen in 2 patients (6.3%) who required tracheostomy due to atelectasis and pneumonia. No late deaths due to pulmonary complications were observed during the follow-up period. The actual survival rate is 68% at 7 years. A low pulmonary function did not, by itself, become a risk factor of cardiac operations, although a pulmonary function test can be used to alert the clinician to possible postoperative complications, including the requirement of tracheostomy. Especially strict control of postoperative respiration is necessary in patients with forced expiratory volume (FEV) of 1.0 <= 800 ml and/or FEV1.0/BSA <= 600 ml/m2.
    Annals of thoracic and cardiovascular surgery: official journal of the Association of Thoracic and Cardiovascular Surgeons of Asia 05/2000; 6(2):100-5. · 0.69 Impact Factor
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    Article: Ultrasonographic demonstration of manipulation-related aortic injuries after cardiac surgery.
    M Ura, R Sakata, Y Nakayama, T Goto
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    ABSTRACT: This study was performed to evaluate the frequency and risk factors associated with new aortal lesions induced by surgical manipulation and their correlation with postoperative stroke. Little is known about the causative mechanism of intraoperative atheroembolism after cardiac surgery. Epiaortic echocardiography was performed before cannulation and after decannulation in 472 patients undergoing cardiac surgery with extracorporeal circulation. A new lesion in the ascending aortal intima was identified in 16 patients (3.4%) after decannulation. New lesions were severe, with mobile lesions or disruption of the intima in 10 patients. Six of the severe lesions were related to aortic damping and the other four to aortic cannulation. Three patients in this group had postoperative stroke. Univariate analysis identified only the maximal thickness of the atheroma near the aorta manipulation site as a predictor of new lesions. The incidence of new lesions was 11.8% if the atheroma was approximately 3 to 4 mm thick and as high as 33.3% if the atheroma was >4 mm, but only 0.8% when it was <3 mm. Total 10 patients (2.1%) sustained neurological complications. Arteriosclerosis obliterans, atherosclerosis of the aorta and new mobile lesions were identified as predictors of strokes. This study demonstrated an association between new lesions created by surgical maneuvers and postoperative stroke. Embolic strokes were more likely to occur if new lesions were complicated with intimal disruption, especially of the mobile type. Modifications in surgical procedures will be needed if thick plaque (especially >4 mm) is noted near the manipulation site.
    Journal of the American College of Cardiology 04/2000; 35(5):1303-10. · 14.16 Impact Factor
  • Article: Craniocervical and aortic atherosclerosis as neurologic risk factors in coronary surgery.
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    ABSTRACT: Advanced age is associated with increased systemic atherosclerosis and is a consistent neurologic risk factor after coronary artery bypass grafting (CABG). We studied prospectively whether varying degrees of a total atherosclerotic score derived from the brain, carotid arteries, and ascending aorta predicted postoperative neuropsychologic (NP) dysfunction and stroke in 177 elderly patients (> or = 60 years) undergoing CABG. Group L (low total atherosclerotic score) had rates of NP dysfunction of 25% and 4%, group I (intermediate) had rates of 33% and 22%, and group H (high) had rates of 79% and 43% on postoperative days 1 and 7, respectively (p < 0.001). The incidence of stroke was higher in group H (14.3%) than in groups I and L (7.8% and 0.9%; p = 0.013). Stepwise logistic regression analysis demonstrated the significant predictors of NP dysfunction on postoperative day 7 to be total atherosclerotic score, peripheral vascular disease, and diabetes mellitus, and those of stroke to be total atherosclerotic score, peripheral vascular disease, and hyperlipidemia. Perioperative evaluation of craniocervical and aortic atherosclerosis is useful to identify a high-risk patient at postoperative NP dysfunction and stroke after CABG.
    The Annals of Thoracic Surgery 03/2000; 69(3):834-40. · 3.74 Impact Factor
  • Article: Analysis by early angiography of right internal thoracic artery grafting via the transverse sinus : predictors of graft failure.
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    ABSTRACT: There has been debate regarding whether technically demanding right internal thoracic artery (RITA) grafting via the transverse sinus can be extensively applied to patients in high-risk groups, such as patients with a small body size, elderly patients, and woman with relatively smaller coronary artery and internal thoracic artery (ITA) diameters. Of the 1456 patients who underwent isolated coronary artery bypass grafting between January 1989 and December 1998 at Kumamoto Central Hospital, 393 patients (mean age, 62.4+/-9.0 years) with the RITA anastomosed to the major branches of the circumflex artery were studied. Left ITA grafting was performed in 384 patients, and in 369, the in situ left ITA was anastomosed to the left anterior descending coronary artery using standard methods. Early postoperative angiography was performed in 381 patients. The RITA was occluded in 4 patients, and string-like artery and significant stenosis were present in 11 and 7 patients, respectively; RITA graft patency was thus 94.1%. Of the preoperative variables and angiographic data, simple and multiple logistic regression analyses identified decreased severity of native stenosis, diffuse sclerosis of native vessels, and residual side branches of the ITA as independent predictors of nonfunctional grafts. The method of ITA grafting did not influence the patency of the graft. The excellent patency rate demonstrated by this study, the largest angiographic study to date of RITA grafting via the transverse sinus, indicates that this technique can provide reliable revascularization of the left ventricle and that it has the potential to be applied to a wide variety of patients with diseased circumflex arteries.
    Circulation 03/2000; 101(6):640-6. · 14.74 Impact Factor
  • Article: Coronary artery bypass grafting in dialysis patients.
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    ABSTRACT: To analyze the characteristic problems of coronary artery bypass grafting in patients with chronic renal failure. Fifty-one consecutive dialysis patients who required isolated coronary bypass grafting over a 9-year period were studied retrospectively. Nine patients (18%) had emergent operation, 4 of whom had intraaortic balloon counterpulsation instituted preoperatively. A mean of 3.3 +/- 1.0 bypasses per patient were grafted; 14 patients (27%) had bypass with two arterial grafts, 13 (25%) of which used left internal mammary artery and gastroepiploic artery and one of which used bilateral internal mammary artery grafts. A mean of 4.2 +/- 2.6 coronary artery segments were calcific according to American Heart Association classification. Eight patients (16%) required operative modifications to avoid manipulating calcific plaques on the ascending aorta. Four patients (7.8%) died, and 15 had nonlethal complications. The actuarial survival rates in 47 hospital survivors at 1, 3, and 5 years were overall 89%, 84%, and 71%, respectively, and estimates for cardiac deaths 93%, 93%, and 82%, respectively. Cardiac event-free rates after coronary artery bypass grafting were 83% and 65% for 3- and 5-year periods, respectively. Calcification of coronary arteries and the ascending aorta is a serious problem in long-term dialysis patients. However using arterial grafts, preferentially, in situ, seems to provide a practical alternative to minimize manipulating the ascending aorta during coronary artery bypass grafting, with acceptable perioperative morbidity and mortality rates and long-term survival.
    The Annals of Thoracic Surgery 11/1999; 68(4):1257-61. · 3.74 Impact Factor
  • Article: Bileaflet mechanical valve (St. Jude Medical valve) replacement in long-term dialysis patients.
    M Ura, R Sakata, Y Nakayama, H Fukui
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    ABSTRACT: Few reports exist on the results of bileaflet mechanical valve (St. Jude Medical prosthesis; St. Jude Medical, Inc, St. Paul, MN) replacement in long-term dialysis patients. We retrospectively reviewed 12 patients, ranging in age from 50 to 86, undergoing long-term renal dialysis who had also undergone mechanical valve replacement at our institution. Operative procedures included aortic valve replacement, aortic and mitral valve replacement, aortic valve replacement and mitral annuloplasty, mitral valve replacement, and modified Bentall's operation. There was 1 hospital death (8.3%). During the mean follow-up period of 37.1 months (range: 5-87 months), there were 2 noncardiac late deaths. Bleeding from the esophageal varix and from a duodenal ulcer occurred in 1 patient with end-stage liver cirrhosis. There were no other major cases of bleeding or cerebrovascular accidents. There were no valve-related complications. All the survivors demonstrated excellent clinical improvement under the NYHA functional classification. Our study demonstrated good early and long-term results of mechanical valve replacement in patients undergoing long-term dialysis. These favorable results support the continued use of mechanical valves in dialysis patients.
    The Annals of Thoracic Surgery 10/1999; 68(3):870-3. · 3.74 Impact Factor