Kanji Kawachi

Effects of hormonal supplements on the maintenance of cardiac function in potential donor patients after cerebral death.

It is well-known that cardiac function in cerebrally dead patients rapidly deteriorates, leaving the organ unfit for donation. This study investigated whether or not cardiac function in patients with cerebral death can be maintained in a desirable condition with hormonal supplementation. In studies of changes in hormones before and after cerebral death, insulin, glucagon, triiodothyronine, thyroxine, cortisol, vasopressin, epinephrine, and norepinephrine values were measured with a lapse of time after cerebral death. Among them, triiodothyronine and cortisol levels were markedly reduced after cerebral death; therefore, these two hormones were selected as hormonal supplements. The average period from the judgment of cerebral death to cardiac arrest was 4.3 days in 12 patients with no hormonal supplement (group I) and more than 11.5 days in 4 patients with hormonal supplement (group II). This period for patients in group II was significantly longer (p less than 0.05). In 2 of the group II patients the hormonal supplementation was discontinued at the familys request, and in the other 2 patients, it was discontinued because of proposed renal donation. Hemodynamic comparisons between the two groups showed that the mean arterial pressure and the left ventricular maximum dp/dt were significantly higher (p less than 0.01) as was the cardiac index (p less than 0.05) on the 3rd day after cerebral death in members of group II. Thereafter, in group II, an excellent hemodynamic state was maintained until hormonal supplements were discontinued. We conclude that the triiodothyronine and cortisol supplements were effective in the maintenance of cardiac function in patients after cerebral death.

Angiographic demonstration of no-flow anatomical patency of internal thoracic-coronary artery bypass grafts

To clarify the no-flow situation of the stringlike internal thoracic artery graft, we angiographically examined such grafts by temporarily occluding the recipient coronary artery with a percutaneous transluminal coronary angioplasty balloon and were able to reveal anatomical patency of the internal thoracic artery graft in 2 patients 1 year and 3 years after the operations. Thus, there is a possibility that internal thoracic artery grafts may continuously maintain anatomical patency even under no-flow situations just like nonfunctioning collateral vessels and may function properly later as a graft when the native coronary flow decreases. Also, this angiographic technique can be a new method for detecting anatomical patency of no-flow and functionally closed internal thoracic artery grafts.

Surgery for coronary heart disease due to mucocutaneous lymph node syndrome (Kawasaki disease): Report of 6 patients

Early and late surgical results in 6 patients with coronary heart disease secondary to mucocutaneous lymph node syndrome (MLNS) (Kawasaki disease) are presented. There were 5 male patients and 1 female patient, ranging in age from 2.5 to 26 years at the time of operation. They had severe coronary artery narrowings, obstructions, and aneurysms with or without mitral regurgitation. Previous myocardial infarction was documented in 5 patients. Aortocoronary bypass grafting utilizing the autologous saphenous vein was performed in 5 patients; in the remaining patient, mitral valve replacement was carried out. No operative or late deaths have been encountered. A long-term bypass graft patency was demonstrated in patients aged 26, 17, and 10 years with resulting clinical, angiographic, or scintigraphic improvements, or a combination of these. However, the graft that had been patent in a 4-year-old boy was found completely obstructed 3 years after surgery without any symptomatic changes. The formation of rich collateral channels was found. The risk of saphenous vein graft closure may be high in young growing children. In older children or adolescents, however, coronary vein bypass grafting for this specific inflammatory coronary artery lesion has been effective with long-term graft patency. Severe mitral regurgitation is also an indication for surgery, but poor left ventricular function associated with mitral regurgitation, probably secondary to myocarditis, persists after surgery and may give rise to future problems.

Effect of warm ischemia and cryopreservation on cell viability of human allograft valves

Fibroblast viability of the allograft valve leaflet has been suggested to affect clinical durability. Warm ischemic time is thought to be one of the critical determinants of cell viability. We assessed cell viability of allograft valves by flow cytometry, using a fluorescein diacetate-propidium iodide stain to characterize the effects of warm ischemia and cryopreservation on viability. Twelve human pulmonary valves with harvest-related warm ischemic times (range, 70 to 520 minutes; mean +/- standard deviation, 225 +/- 157 minutes) were studied by flow cytometry. We assessed cell viability of the allograft valve leaflets before and 30 days after storage. A significant negative correlation was found between warm ischemic time (x minutes) and cell viability (y%) before (y = -0.024x + 96.7; r2 = 0.62; p = 0.002) and after 30 days of storage (y = -0.036x + 94.0; r2 = 0.86; p = 0.001). Cell viability of the cryopreserved allograft valves was well preserved (> 70%) with a warm ischemic time less than 520 minutes (8.7 hours).

Systolic and diastolic function after patch reconstruction of left ventricular aneurysms

Left ventricular function after patch reconstruction for postinfarction left ventricular aneurysms is largely unknown. In this study, 16 patients with an anteroseptal-lateral left ventricular aneurysm were treated by reconstruction of the left ventricle using a Dacron patch. Coronary artery bypass grafting was performed concomitantly in 9 patients. The size of the patch used was 57% +/- 19% of the resected myocardial scar area, including the sewing cuff area to be sutured. In these patients, the ejection fraction increased significantly from 0.28 +/- 0.12 to 0.39 +/- 0.12 (p = 0.007) at rest and from 0.32 +/- 0.14 to 0.41 +/- 0.10 (p = 0.008) during exercise. The left ventricular end-diastolic pressure and left ventricular end-diastolic volume index were reduced significantly from 14 +/- 7.0 to 8 +/- 3.2 mm Hg (p = 0.032), and from 178 +/- 116 to 92 +/- 21 mL/m2 (p = 0.016). The peak filling rate was improved significantly from 1.2 +/- 0.47 to 1.8 +/- 0.6/s (p = 0.048) postoperatively. The ratio of the peak flow velocity during the atrial kick phase to the peak flow velocity in the rapid filling phase, at the level of the mitral valve, improved (p = 0.016) after operation and remained improved up to 16 to 24 months after operation. Patch reconstruction of the left ventricle resulted in the recovery of systolic and diastolic function soon after operation, which has persisted into the late postoperative period.

Internal thoracic artery grafting for congenital coronary malformations

We report 2 patients with congenital coronary anomalies (atresia of left main coronary artery and anomalous origin of the left coronary artery from the pulmonary artery) successfully treated with single or double internal thoracic artery grafting. Because the internal thoracic artery has a potential for circumferential as well as longitudinal development, and because of the uncertainty of ultimate vein graft function, we believe that the internal thoracic artery is the best graft material for the treatment of congenital coronary malformations requiring bypass operation in children, adolescents, or even in adults.

Lower extremity ischemia secondary to internal thpraciccoronary artery bypass grafting

Vascular complications associated with the use of the internal thoracic artery as a conduit for coronary artery bypass are infrequent. However, acute limb-threatening ischemia can occur after the use of the internal thoracic artery for myocardial revascularization when this vessel forms an important collateral to an obstructed aortoiliac artery system. Although this is a rare complication, the consequences are devastating. Due to the risk of peripheral vascular insufficiency, we now perform simultaneous revascularization of the myocardium and the lower extremity when an internal thoracic artery that appears to be a major collateral to the ipsilateral aortoiliac system is used.

Annuloplasty for severe mitral regurgitation due to dilated cardiomyopathy

We present a 74-year-old woman who underwent corrective annuloplasty for severe mitral regurgitation due to dilated cardiomyopathy. Postoperatively, congestive heart failure improved, with her New York Heart Association status changing from IV to II, although her cardiac functional improvement was minimal. Severe mitral regurgitation may be the indication for annuloplasty in symptomatic patients with dilated cardiomyopathy when cardiac transplantation is not indicated.

A pathohistological and biochemical study of arteriosclerosis in the internal thoracic artery, a vessel commonly used as a graft in coronary artery bypass surgery

Pathohistological and biochemical studies were conducted on the severity of arteriosclerosis in the internal thoracic artery (ITA), an artery commonly used for coronary artery bypass grafting (CABG). For the pathohistological examination, 26 bilateral ITAs and 13 left anterior descending coronary arteries (LADs) obtained in full length from 13 autopsy cases, none of which had died of arteriosclerotic heart disease, were used. The ratio of the thickness of the intima to that of the media (R) was used as the index for arteriosclerosis. ITAs and LADs were classified as grades I to IV according to the value of R. The R of the ITAs was approximately 1/10 that of the LADs (P<0.01). Most ITAs showed a low arteriosclerotic grade, with no variation in arteriosclerosis along their length and a low R in all segments. No difference was found between right and left ITAs. Biochemical examination was conducted on 12 ITAs and 11 LADs, obtained from 12 different and unselected autopsy cases. The lipid content in the vascular wall was determined to evaluate the severity of arteriosclerosis, with the following results: Total cholesterol, 5.5±1.8 and 17.8±13.6 μg/mg wet weight (P<0.05); triglyceride, 90.4±90.3 and 114.4±117.2 μg/mg wet weight (n.s.); and phospholipid, 7.4±3.9 and 11.2±3.9 μg/mg wet weight (P<0.05), respectively, for the ITAs and LADs. These findings thus demonstrate that arteriosclerosis of the ITA in Japanese people is very mild, compared to that of the LAD in the same individuals.

Development of a second-generation radiofrequency ablation using sintered MgFe2O4 needles and alternating magnetic field for human cancer therapy

Magnetic metal particles are known to induce heat energy under an alternating magnetic field (AMF). We developed a local tumor-heating device incorporating an MgFe(2)O(4) needle for the purpose of mild ablation for cancer treatment. A needle made from sintered MgFe(2)O(4) particles was embedded in the hepatic or breast tumors. Tumors were then heated by the energy dissipated from the needle exposed to an AMF. We sequentially evaluated histological changes, cellular activity of tumors, and the extent of thermal effect using nicotinamide adenine dinucleotide (NADH) diaphorase and terminal deoxynucleotidyl tranferase-mediated digoxigenin-DUTP nick-end labeling (TUNEL) staining. The mean temperature of the tumor tissue during heating was about 60 degrees C. Nuclei of the tumor cells became hyper-chromatin immediately after heating. The injured area spread progressively until 3 days after heating; when the area was surrounded by fibroblasts (meaning is not clear). Tumors disappeared after treatment without complications. This is the first time that the complete death of tumor cells has been realized by raising the tumor temperature above 60 degrees C using the heat generated by magnetic metal particles exposed to AMF. This device may be useful in the future for local hyperthemic treatment of human cancers.