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T Nishii

Publications and source records attributed to T Nishii.

At least 73 records · Page 4Linked to original sources
PubMed1989

[Coronary artery bypass surgery with internal mammary artery grafts: clinical and angiographic results].

We report clinical and angiographic results of coronary artery bypass grafting (CABG) surgery in 307 patients. IMA grafts can be utilized in the wide ranges of patient ages and/or coronary lesions including left main trunk disease, and have good adaptive capability to coronary flow demand with very low probability of atherosclerotic changes. Postoperative (5.2 +/- 4.4 months) patency rates for IMA grafts and SVG were 96% and 86%, respectively; a significant difference (p less than 0.001). From the benefits of this graft, the use of IMA has become a routine procedure in our CABG surgery and the rate of multiple bypasses with IMA grafts has increased recently. The late cardiac events have significantly (p less than 0.05) decreased in patients with the IMA graft than in those without it. We believe that the use of IMA has improved the quality of CABG in Japanese patients and this operative modality can bring better late results than multivessel PTCA.

Adolescent↗
PubMed1989

Quantitative and morphological studies of the bones by mathematical morphology--theory and practice of mathematical morphology.

To quantitatively analyze internal bone structures, trabecular bones were quantitatively studied through the application of mathematical morphology. Mathematical morphology considers the shape of the analyze objects and utilizes image processing theory in an approach that is extremely effective on for studying the complex shapes of trabecular bones. This paper describes quantitative studies made of trabecular bone density and width, trabecular specific length per unit area, and trabecular bone orientation.

Bone Density↗
PubMed1989

[A right common iliac aneurysm perforating into the inferior vena cava with resultant congestive heart failure].

A 69 year-old male with a right common iliac aneurysm perforating into the inferior vena cava was admitted with severe cardiomegaly and dyspnea. He had been suffering from recurrent congestive heart failure for the last 8 years prior to surgery. At operation, the fistula of 15mm diameter was closed with interrupted sutures of 3-0 nylon with pledgets within the aneurysm by controlling bleeding from the fistula by digital compression. The right common iliac aneurysm was resected and replaced with a double velour knitted dacron graft of 10mm diameter. The postoperative course was uneventful. The CTR was reduced to 57% from 70%, and the cardiac index was normalized from 6.10 to 3.39 l/min/m2. This complication is rare with only 4 previous reports in Japan. Hemodynamic improvements were dramatic after surgery in spite of poor response to medical treatments. This complication should be surgically managed as soon as the diagnosis is confirmed.

Aged↗
PubMed1989

[Surgical treatment of postinfarction ventricular septal perforation--the difference between a cardiogenic shock group and a congestive heart failure group].

Twelve patients with postinfarction ventricular septal perforation (VSP) were divided into 2 groups based upon the preoperative status and the time interval between the operation and the occurrence of VSP after acute myocardial infarction (AMI). Group I were in cardiogenic shock unresponsive to either pharmacologic supports or IABP, and needed an emergency repair of VSP. The other group (group II) were in congestive heart failure responding to some extent to pharmacologic supports and IABP, and VSP of this group was repaired on the elective or semiemergency basis. Group I comprised of 7 patients, 5 males and 2 females, with a mean age of 65.9 +/- 12.6 years, and group II included 5 patients, 2 males and 3 females with an averaged age of 72.6 +/- 3.4 years. The mean time duration between AMI and the operation, and between the occurrence of VSP and the operation were 3.1 and 1.6 days in group I and 13.4 and 8.0 days in group II. The operative mortalities were 57% in group I and 0% in group II, a remarkable difference. The reasons why group I had a poor prognosis were analysed and were found as follows: (1) group I sustained a larger AMI of anteroseptal area together with the lateral and/or inferior infarctions more often than group II. (2) Group I had frequently multiple organ failure (MOF) even prior to operation due to cardiogenic shock. (3) Group I had severer right ventricular failure than group II, in which the right atrial pressure was markedly elevated. In group I, the right heart failure remained and was prolonged even after surgery reflected by the RAP/LAP ratio over 1 and finally resulting in MOF. To improve surgical results in group I, the operation should be undertaken on the emergency basis before MOF is completed, and patch reconstruction of the left ventricular free wall is recommended in patients with a wide AMI and a high positioned anterior septal perforation. When RV failure is dominant, not only a LV assist device but also a RV assist device may also improve the results.

Aged↗
PubMed1989

[Clinical experiences with a new membrane oxygenator with low priming volume (D702 MASTER FLO 51), studies during pulsatile and constant flow perfusion].

The newly developed oxygenator "D702" is a compact hollow fiber membrane oxygenator with a priming volume of 170 ml. The maximum flow allowance is 4 liters per/minute. We used this oxygenator in 16 patients (11 infants and children, and 5 adults) undergoing various open heart surgery, and function of this oxygenator was studied. Pulsatile cardiopulmonary bypass was performed in 8 patients and nonpulsatile constant flow perfusion was employed in the remaining 8 patients. Our clinical experience showed excellent maintenance of PaO2 and PaCO2 during both pulsatile and constant flow bypasses. A low pressure drop was encountered across the membrane oxygenator, and therefore, this oxygenator is applicable for pulsatile cardiopulmonary bypass. The D702 is a very useful and applicable for a wide range of patients from infants to adults with a small body structure.

Adolescent↗
PubMed1989

[Successful recovery and long-term survival following postcardiotomy (mitral valve replacement) cardiogenic shock by means of a left ventricular assist device].

A 48-year-old woman who had had mitral regurgitation associated with hypertension and left ventricular hypertrophy underwent mitral valve replacement with a 29 mm xenograft. Following the uneventful procedure, she could not come off cardiopulmonary bypass for 6 times even with an aid of IABP and with re-replacement of the mitral valve using a 29 mm Duromedics prosthesis because of the fear of xenograft malfunction. A left ventricular assist device (LVAD) was then utilized with a resultant dramatic recovery from profound postcardiotomy cardiogenic shock, and cardiopulmonary bypass was successfully terminated. Postoperatively, her hemodynamics were maintained with a LVAD and IABP. Heparin was used to keep the prosthesis from blood clotting by monitoring the ACT. The heart recovered gradually from intraoperative myocardial damage and the LVAD was successfully removed at the 5th postoperative day. Postoperative cardiac catheterization studies showed decreases in left ventricular wall motion and ejection fraction, although improvements of pulmonary hypertension and left ventricular end-diastolic pressure at rest were observed. At present, 1 year and 9 months after the use of LVAD, she is leading nearly normal life of NYHA grade 1. Because of the excellent present clinical condition of this patient, the benefit of a LVAD in perioperative cardiogenic shock is stressed.

Female↗
PubMed1988

Relations of preoperative hemodynamics and coronary blood flow to improved left ventricular function after valve replacement for aortic regurgitation.

In this study of the limits of reversibility of left ventricular function after aortic valve replacement for aortic regurgitation, measurements were made of pre- and postoperative coronary blood flow and left ventricular volumes. Eighteen patients who had undergone aortic valve replacement for pure aortic regurgitation using the Björk-Shiley valve or the Bicerval valve were restudied an average of 8 +/- 3 months after surgery. Postoperative left ventricular end-systolic and end-diastolic volumes returned to near normal values. The slight left ventricular wall thickening apparent before surgery remained unchanged after surgery and, consequently, left ventricular mass, though somewhat reduced, remained abnormally high. Ejection fraction, which was low preoperatively, returned to normal postoperatively. Total coronary sinus blood flow decreased after surgery, but coronary sinus blood flow per 100 g of left ventricular mass increased. This recovery of coronary flow per unit mass was believed to cause the improvement in left ventricular function. A significant correlation was found between postoperative systolic function and preoperative left ventricular end-systolic and end-diastolic volumes, wall thickness and, especially, left ventricular mass, the latter indicating that, if preoperative left ventricular mass is less than 350 g/m2, postoperative improvement of systolic function is attainable. Another significant correlation was indicated by measurements of coronary sinus blood flow per 100 g of left ventricular mass. If this is greater than 35 ml/min before surgery, a postoperative improvement in systolic function to within the normal range may be expected.

Adult↗
PubMed1988

Excellent patency and growth potential of internal mammary artery grafts in pediatric coronary artery bypass surgery. New evidence for a "live" conduit.

Coronary artery bypass grafting in pediatric patients provides a unique opportunity to evaluate the characteristics of graft material. Twelve pediatric patients with severe coronary artery involvement secondary to Kawasaki disease underwent coronary artery bypass grafting with internal mammary artery and autologous saphenous vein grafts. Eleven patients were boys and one was a girl; their ages ranged from 5 to 13 years (mean age +/- SD, 8.7 +/- 3.0 years). These 12 patients had 17 internal mammary artery and 11 autologous saphenous vein grafts with a mean value of 2.3 +/- 0.7 grafts per patient. Five patients underwent bilateral internal mammary artery grafting with or without concomitant autologous saphenous vein grafting. There was no mortality, and all patients are leading almost normal lives, although strenuous exercise is still prohibited for some. Biplanar cineangiography was performed before and 1 month after (early postoperative period) coronary artery bypass grafting in all patients and was repeated more than 1 year after (late postoperative period) bypass in eight patients. Changes in graft diameter and graft length were assessed by computer-assisted graphic analysis of 10 internal mammary artery grafts and of seven saphenous vein grafts between the early and late postoperative periods. Patency rates of saphenous vein grafts and of internal mammary artery grafts were 91% and 100%, respectively, at the early postoperative period (p = NS), and 50% and 100%, respectively, at the late postoperative period (p less than 0.05). In addition to the excellent patency of internal mammary artery grafts in the late postoperative period, an in situ internal mammary artery graft was found to have grown 125% in length with 112% body growth (112% body surface area) (r = 0.88, p less than 0.001) and to have enlarged 149% in diameter when the native coronary stenosis was tight. In contrast, the lengths of saphenous vein grafts either failed to change or were slightly decreased at the late postoperative period (p = NS). Growth potential of the internal mammary artery graft provides a new demonstration of the viability and adaptability of this graft. We conclude that the internal mammary artery graft is a "live" conduit with potential for growth and adaptation. This growth potential may be the most important reason for its excellent long-term patency, which suggests that in situ internal mammary artery grafts are the graft of choice for pediatric coronary artery bypass grafting.

Adolescent↗
PubMed1987

Results of internal mammary artery-coronary artery bypass surgery and the characteristics of internal mammary artery grafts.

Coronary artery bypass grafting utilizing the internal mammary artery (IMA) was performed in 108 patients with an operative mortality (less than 1 month) of 0% and a hospital mortality of 1.9%. The IMA was used most often in the left anterior descending artery system in combination with saphenous vein grafts (SVG) to the right and left circumflex artery systems. Although the IMA flow was smaller than the SVG flow when measured intraoperatively by an electromagnetic flow meter, postoperative clinical, electrocardiographic, isotopic, angiographic and coronary sinus flow-metric studies all demonstrated that the IMA can respond well to myocardial blood flow demand both at rest and during exercise, resulting in excellent clinical improvements with no detectable signs of flow deficiency. In addition, no signs of ischemia were detected in any of the 15 patients with stenosis in the left main trunk treated with an IMA graft. The IMA graft appears to have a great adaptive capacity to meet increased myocardial demand. Postoperative angiography performed at an average of 3 months after surgery in 60 unselected patients demonstrated an IMA patency rate of 98% in comparison with 88% patency in SVGs to the left anterior descending artery (p less than 0.05). Not only the patency rate, but also the graft wall characteristics were much better in IMA grafts than in SVGs. Some SVGs showed marked wall irregularity as early as 3 months after surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗