[Studies on tissue PO2 and biochemical analysis of the skeletal muscle of legs with chronic arterial occlusive diseases]

Measurements of maximum tissue PO2 during 100% O2 inhalation (PtO2max) and biochemical analysis of the skeletal muscle were performed in 3 legs without ischemia and 14 legs with chronic arterial occlusive disease requiring amputation. There were significant good correlations between PtO2max and levels of pH, lactate, enzymes (CPK, LDH, Aldolase) and ATP in the skeletal muscle with ischemia. In regions in which PtO2max was below 10mmHg, ischemic changes in the muscle were considered to be irreversible. On the contrary, primary wound healing was obtained in regions with 40mmHg or more of PtO2max. Measurements of the PtO2max of the ischemic muscles provided much useful information concerning the reversibility of muscle ischemia and for decision of the amputation level.

Magnetooptic recording readout performance improvement

This paper describes magnetooptical (MO) readout and recording performance improvement that increase the MO disk drive performance. In regard to readout performance, a <60-dB readout carrier-to-noise ratio is achieved for an MO disk with a polycarbonate substrate. Also, in regard to recording performance, a new MO head is presented that achieves high optical transmission efficiency (~57%) without sacrificing the readout performance. As a result, disk rotation speed can be increased, and the data transfer rate can be improved.

Recent morbidity trends in myocardial infarction in Japan: investigation of death certificates and the survival rates at coronary care units

To elucidate recent trends in the mortality and morbidity of myocardial infarction (MI), we investigated death certificates and changes in the survival rate of MI patients at coronary care units (CCUs), which may affect the death rates. For all cases of MI, acute heart failure (AHF), heart failure (HF) as underlying cause, and hypertension as underlying cause with HF or AHF (categorized as hypertensive heart disease) on death certificates in two rural and two urban populations between 1981 and 1984, medical records were reviewed and case histories obtained from interviews with patients' families to validate the diagnosis. The number of MI deaths on the death certificates was not underestimated because some MI deaths were misdiagnosed as AHF, HF and hypertensive heart disease and some MI death certificates were misdiagnosed. Survival of MI patients at CCUs improved in several major cities, Tokyo, Osaka, Wakayama and Asahikawa between 1978 and 1984; a total of 4318 MI deaths were estimated to be averted by CCUs in 1984 compared with the number of deaths in 1978. Therefore, improvement of MI cases at CCUs may be one of the factors attenuating the rise in death rates in all of Japan.

[Surgical treatment for thoracoabdominal and suprarenal abdominal aortic aneurysm]

We experienced 4 cases of thoracoabdominal and suprarenal abdominal aortic aneurysm in the last 6 months. There were 3 males and 1 female ranging in age from 43 to 66 years, 2 with an etiology of aortitis syndrome, 1 with non-specific inflammation and 1 with atherosclerosis. In all cases the modified Hardy procedure was employed. A 18 to 22mm X 9 to 11mm bifurcation, double velour woven dacron graft was sutured from the side of the lower descending thoracic aorta to the side of both common iliac arteries. Grafts of the same kind as above 6 to 7mm in size were attached from the main graft to major visceral arteries by end-to-end or end-to-side anastomosis. A permanent aortic-excluding clamp was attached to the normal aorta just proximal to the aneurysm. Another clamp, or double ligature with silk, was placed on the lower abdominal aorta or both common iliac arteries distal to the aneurysm. No renal and spinal preservation of any kind was employed, but renal failure and paraplegia were not recognized in any of the cases. One patient died 2 days and another 21 days after the operation due to uncontrollable bleeding and multiple organ failure. The other two are doing well.

[Several factors influencing the male sexual function in patients with atherosclerotic disease]

Patients with arteriosclerosis obliterans (ASO, n = 58), abdominal aortic aneurysm (AAA, n = 27) and the combined disease (n = 4) were the subjects of this study. All patients were evaluated by retrograde aortography and questioned personally as to their present male sexual function. The penile and ankle systolic pressure index (PSPI and ASPI) of patients with ASO were measured using a Doppler device, but in the patients with AAA, only the PSPI was taken. Several factors relating to male sexual function, such as, age, PSPI, ASPI, sites of the arterial occlusion or dilatation, classification of the ischemic symptoms according to Fontaine's category, numbers of pulsations of the femoral artery, were statistically analysed. All of the patients with both diseases, 66 percent of those with ASO and 52 percent of those with AAA were impotent. In the patients with AAA, the PSPI of the potent group was not significantly higher than that of the impotent group; however, in patients with ASO, the PSPI of the former group was significantly higher than that of the latter group. In the patients with ASO, a significant correlation between the PSPI and the ASPI (r = 0.49, p less than 0.01) was found. When a PSPI value (PSPI = 0,70) was chosen as a demarcation between the impotent group and the potent group, 84 percent of the patients with ASO were correctly classified. However, when the ASPI (ASPI = 0.45) was used, only 69 percent were properly classified.(ABSTRACT TRUNCATED AT 250 WORDS)

Computer-assisted education system for arrhythmia (CAESAR)

A computer-assisted education system for arrhythmia (CAESAR) was developed for students to acquire the ability to logically diagnose complicated arrhythmias. This system has a logical simulator of cardiac rhythm using a mathematical model of the impulse formation and conduction system of the heart. A simulated arrhythmia (ECG pattern) is given on a graphic display unit with simulated series of the action potential of five pacemaker centers and the "ladder diagram" of impulse formation and conduction, which show the mechanism of that arrhythmia. For the purpose of the evaluation of this system, 13 medical students were given two types of tests concerning arrhythmias before and after 2-hr learning with this system. The scores they obtained after learning increased significantly from 73.3 +/- 11.9 to 93.2 +/- 3.0 (P less than 0.001) in one test and from 47.2 +/- 17.9 to 64.9 +/- 19.6 (P less than 0.001) in another one. These results proved that this CAI system is useful and effective for training ECG interpretation of arrhythmias.