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Biomedical subjects

M Nishimi

Publications and source records attributed to M Nishimi.

24 records · Page 2Linked to original sources

An evaluation of long-term results over 10 years after intracardiac repair of tetralogy of Fallot.

A follow-up study was conducted of 166 patients who had survived for more than 10 years after total correction of tetralogy of Fallot. The total number of patients in NYHA class I was 141 (85%); the other 25 patients had been medically treated or had followed a prudent life style. The factors which caused postoperative symptoms were residual lesions and ventricular arrhythmia. Ultrasonic echocardiography showed that among 72 patients with transannular patch, 68 (95%) showed moderate or severe pulmonary incompetence. There was a correlation of gamma = 0.43 between the severity of pulmonary incompetence and cardiothoracic ratio in the 48 patients without any residual lesions, while two cases with severe pulmonary incompetence showed obvious right ventricular failure. Ambulatory ECG monitoring was employed to study 53 patients. As a result, 21 patients were found to present solitary moderate or severe pulmonary incompetence, while premature ventricular contraction of Lown's grade 4A was seen in nine patients (42.9%). In conclusion, it is considered essential to carefully follow up patients after intracardiac repair of tetralogy of Fallot, especially those with severe pulmonary incompetence.

Adolescent↗

[Percutaneous transluminal angioplasty of a constricting coronary artery bypass graft: a case report].

A case with percutaneous transluminal coronary angioplasty (PTCA) for the stenosis of saphenous vein bypass graft was reported. A 68-year-old woman developed repeated effort angina two months after emergency triple CABG. Coronary angiographic study revealed 90% stenotic lesion in a sequential vein graft which was located between proximal and distal OM. PTCA was successful to dilate the stenotic lesion from 90% to 25% narrowing. She has been free from angina after the CABG and PTCA.

Aged↗

Ultrastructural alterations of right and left ventricular myocytes in tetralogy of Fallot.

We examined the ultrastructure of right and left ventricular myocardial biopsies obtained prior to cardiopulmonary bypass in fourteen patients undergoing total correction of tetralogy of Fallot (TOF). Twelve patients were undergoing primary one-stage repair and two patients had had a previous Blalock-Taussig shunt operation. The ages of the patients ranged from 3 to 35 years. In left ventricular (LV) myocytes, the sarcolemma often formed pouches filled with mitochondria and the muscle fibers showed a disoriented arrangement. In addition, the myofibrils showed hypercontraction and the Z-bands were thickened; the degree of the myofibril contraction was more severe than that in right ventricular (RV) myocytes. These ultrastructural findings are similar to those observed in myocytes under hypoxic conditions. The number of lysosomes in LV myocytes, but not in RV myocyte increased in the older patients. While we have not established a causal relationship between the ultrastructural findings and clinical features in our cases, our observations are consistent with the possibility that early total correction of TOF may be required to prevent the development of hypoxic changes and degeneration of heart muscle.

Adolescent↗

Improvement of postoperative graft patency rate for coronary revascularization.

For coronary artery revascularization, the long term patency rate of internal thoracic artery (ITA) is excellent and arterial conduit for coronary bypass grafting (CABG) has been actively pursued. Application of the right gastroepiploic artery (GEA) is on the increase but, the patency of the GEA graft is more technically demanding than that of ITA. To improve early postoperative graft patency for coronary artery bypass grafting (CABG) for arterial graft, we modified the technique for anastomosis and demonstrated the patency by postoperative angiogram in 26 consecutive patients receiving CABG. The graft was anastomosed to the coronary artery using two 8-0. Prolene sutures for arterial graft and 7-0 Prolene sutures for saphenous vein (SV) graft. The heal and toe sides of the graft were sutured separately by the parachute technique (double parachute technique), followed by running suturing and typing at bilateral sides. The number of distal anastomoses was 3.4/patient and 44 arterial grafts and 40 SV grafts were used for coronary revascularization. Arterial grafts consisted of 33 ITAs, 9 GEAs, and two inferior epigastric arteries. The angiograms taken 10 to 14 days after operation demonstrated 100% patency rate of arterial grafts and 39 out of 40 SV grafts were patent. The overall patency rate in the early postoperative period was 98.8% The "double parachute" technique for CABG is highly accurate anastomosis with good visualization and the patency rates for all kinds of grafts were found to have improved.

Adolescent↗