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Biomedical subjects

M Yasuno

Publications and source records attributed to M Yasuno.

At least 55 records · Page 3Linked to original sources

Myocardial infarction after acute carbon monoxide poisoning: case report.

A 28-year-old man with acute myocardial infarction after carbon monoxide poisoning is reported. He had chest pain after the exposure to carbon monoxide. The electrocardiogram, serum enzymes, and technetium-99m pyrophosphate scintigrams showed anterior myocardial infarction. The coronary angiogram, which was performed one month after the onset, showed no visible atherosclerotic lesion. As to the cause of myocardial infarction, it is assumed that carbon monoxide reduced the oxygen supply to the myocardium and might induce coronary artery spasm with or without accompanying coronary thrombosis.

Adult↗

Clinical experience with a new rate-responsive TX pacemaker.

In this report, we describe our initial experience with a new rate-responsive TX pacemaker in 10 patients. This pacemaker system uses a conventional transvenous ventricular electrode, which senses the evoked QT interval after a ventricular paced beat, as an indicator of physiological metabolic demand. Implantation of the TX pacemaker does not differ from that of conventional VVI units, and two special modes are available after implantation: TX and VVI mode. Bicycle ergometer tests showed that significantly higher rate response and exercise ability were achieved during the TX mode compared with the VVI mode (mean maximal heart rate: 115 +/- 13 bpm vs 96 +/- 21 bpm, p less than 0.01, and mean maximal exercise time; 10.7 +/- 3.9 min vs 8.0 +/- 3.8 min, p less than 0.01, respectively). In one patient, cardiac index was measured by a thermodilution method during the bicycle ergometer test, which confirmed that an adequate increase in cardiac index (rest: 3.38 liters/min/m2, vs exercise; 7.34 liters/min/m2) was obtained by an increase of the pacing rate (rest: 72 bpm vs exercise: 128 bpm). Our results show that physiological rate-responsive pacing using the QT interval provides a simple means of increasing the heart rate and cardiac index.

Aged↗

Importance of coronary collaterals for restoration of left ventricular function after intracoronary thrombolysis.

In an evaluation of the role of coronary collaterals in the early period of acute myocardial infarction (AMI), 30 patients with acute total coronary occlusion treated with intracoronary thrombolysis 2 to 8 hours after the onset of symptoms were studied. Only 13 patients with well-developed collaterals in the early period of AMI and successful thrombolysis showed improvement of global and regional ejection fraction (EF) from the acute phase to the chronic phase (global EF from 50% to 71%, p less than 0.001; regional EF from 25.4% to 49.2%, p less than 0.001). In patients with no or less well-developed collaterals and successful thrombolysis, global and regional EF were similar to those in patients in whom thrombolysis was unsuccessful. Among the 19 patients with successful thrombolysis, there was no significant correlation between the duration of ischemia and the improvement of regional EF (r = -0.03, difference not significant). These data suggest that the extent of coronary collateral vessels in the early period of AMI is an important determinant of restoration of left ventricular function after intracoronary thrombolysis.

Acute Disease↗

Effects of percutaneous transluminal coronary angioplasty: intracoronary thrombolysis with urokinase in acute myocardial infarction.

Coronary angiography and percutaneous transluminal coronary angioplasty (PTCA) were performed in 32 patients with evolving acute myocardial infarction. Of the 25 patients with complete occlusion of an infarct-related coronary artery, in 18 (72%) the occluded vessel was successfully opened by an intracoronary infusion of urokinase. With a small dose of urokinase the successful recanalization was achieved in only 25%; with a larger dose it was achieved in 94%. After PTCA, all patients received glucose-insulin-potassium solution for 76 hours. Repeat angiography 42 days later showed a patent coronary artery in 12 (group A) of 18 patients with successful PTCA. In group A, left ventricular ejection fraction increased from 51 +/- 13% to 72 +/- 10% (p less than 0.01) and regional wall shortening from 4.5 +/- 9.5% to 29 +/- 19% (p less than 0.01). In contrast, these variables did not change significantly in patients with unsuccessful PTCA or late reocclusion of an infarct-related vessel (group B). These data suggest that successful PTCA with sustained patency of an infarct-related coronary artery has a beneficial effect on the salvage of the jeopardized myocardium, and glucose-insulin-potassium therapy may enhance the beneficial effect of PTCA.

Adult↗

Angiographic and pathologic evidence of hemorrhage into the myocardium after coronary reperfusion.

Severe myocardial hemorrhage can occur as a potential adverse effect of reperfusion therapy in evolving myocardial infarction. This report describes a 83-year-old man, who showed angiographic evidence of extravasation of contrast medium from the reperfused right coronary artery into the inferoposterior left ventricular wall. At autopsy, severe hemorrhage was transmurally observed in the inferoposterior wall of the left ventricle. The finding of extravasation is a useful angiographic sign of the production of hemorrhage during coronary reperfusion therapy, and great attention should be focused to the existence of this sign to prevent further hemorrhage.

Aged↗

Pulmonary embolism as a complication of transfemoral arteriography--incidence, symptoms, and prevention.

In order to evaluate the pulmonary embolism as a complication of transfemoral arteriography, we performed lung perfusion scintigrams before and after arteriography in consecutive 120 patients. Of the initial 60 patients who did not receive subcutaneous low-dose heparin, 19 (32%) demonstrated new pulmonary perfusion defects. There was no significant difference in regard to the incidence of new defects with or without right heart catheterization. On the other hand, in the latter 60 patients who received prophylactic heparin, the incidence of new defects decreased to 10%, without increasing clinically important bleeding. We believe that the source of emboli is from the leg vein thrombosis due to compression of the groin and subsequent bed rest. These data suggest that pulmonary embolism is a more common complication of transfemoral arteriography than previously appreciated and low-dose heparin is useful in reducing this complication.

Adult↗

[A case of Marfan's syndrome with a ruptured distal middle cerebral aneurysm].

A case of ruptured distal middle cerebral aneurysm is reported, A 20-year-old man with Marfan's syndrome suffered from sudden loss of consciousness. A CT scan and cerebral angiogram revealed a distal middle cerebral aneurysm with a large intracerebral hematoma. The aneurysm was clipped and the hematoma was evacuated successfully. This case is presented and the literature related to the aneurysm associated with Marfan's syndrome is reviewed.

Adult↗

Enzyme immunoassay for the quantification of mitomycin C using beta-galactosidase as a label.

A mitomycin C (MMC) antibody was produced following immunization of rabbits with a MMC-bovine serum albumin conjugate, which was newly synthesized by coupling MMC to mercaptosuccinylated bovine serum albumin via a cross-linker, N-maleoyl aminobutyric acid. Enzyme labeling of MMC was performed using beta-D-galactosidase (EC 3.2.1.23) via m-maleoyl benzoic acid. An enzyme immunoassay for MMC was developed utilizing these reagents by a double-antibody technique. The standard curve of the assay was linear on a logit-log plot, and the lower limit of detection was 12 nM (0.2 ng/tube) so the enzyme immunoassay was found to be approximately 25 times more sensitive than a microbiological assay. Further, the enzyme immunoassay is practically free from interference by any other anticancer drugs. No significant decrease in MMC immunoreactivity was observed following 24 hr of incubation of the drug in normal human serum or urine at 37 degrees. Using this assay, serum or urine levels of MMC can be determined accurately after administration of the drug to rats at a single dose of 600 micrograms/kg. The sensitivity and specificity of the enzyme immunoassay for MMC should provide a valuable new tool for use in pharmacokinetic and toxicity studies of MMC.

Animals↗