Search PubMed⌕ Search

Biomedical subjects

K Hayasaki

Publications and source records attributed to K Hayasaki.

At least 55 records · Page 3Linked to original sources
PubMed1984

The clinical feature of pre-hospital phase of acute myocardial infarction--the advantages and limitations of the MCCU.

For purposes of evaluating the clinical features in the prehospital phase of acute myocardial infarction, 22 patients presenting prehospital syncope and patients presenting in-hospital re-attack were chiefly studied. Cardiac or ventricular standstill, acute mechanical failure, ventricular fibrillation, serious block, bradycardia-hypotension syndrome, cardiogenic shock, cardiac failure and cardiac rupture may be cited as the complications likely to occur in the early phase of the onset of acute myocardial infarction. Among these complications, cardiac or ventricular standstill results from overactivity of the vagus nerve, and acute mechanical failure is a result of drastically decreased cardiac output due to extensive infarction. There is no report of either complication, and both may be considered to be the fatal complications occurring almost simultaneously with the onset of acute myocardial infarction. The time intervals from the onset of symptoms to hospital admission were perspectively analyzed on 72 patients transported by the MCCU and 139 by ordinary ambulance. The interval from the onset of symptoms to medical help and that from the examination by personal physician to the call for ambulance were the greatest of all time factors, while the interval for emergency transport of the patient was short. There was no significant difference in the interval to hospital admission between the patients transported by the MCCU and those by ordinary ambulance. However, the in-transit death rate was 1/72 patients transported by the MCCU and 8/139 by ordinary ambulance: in other words, this death rate tended to be high in the latter. Twenty-two normal volunteers were studied for changes in heart rate, blood pressure and double product with the speed of transport. The transport at a low speed caused less changes in these parameters than that at a high speed.

Aged↗
PubMedDate not supplied

Feasibility of ventricular function analysis by digital subtraction angiography.

Continuous or cine mode of digital subtraction angiography (DSA) following intravenous injection of contrast media was evaluated in regard to feasibility of obtaining physiologic data in cardiac abnormalities. Computer programs for cardiac function analysis including stroke volume, ejection fraction and display of left ventricular wall motion in end-diastole and end-systole have been developed with use of automatic contour plotting and densitometry for depth information. Experiments with contrast-filled balloons demonstrated good correlation between the true volumes and the calculated volumes. Clinical study also demonstrated good correlation between the values obtained from conventional left ventriculography and DSA.

Angiography↗
PubMedDate not supplied

Determination of left ventricular volumes with use of DSA density values.

A computer program was developed to obtain left ventricular volumes from the density values of DSA. The highest density value along the horizontal pixel line over the left ventricle in 30 degrees RAO was considered to correspond to the greatest width on the same level of 60 degrees LAO. The left ventricular volume was obtained by converting the density values into the width and integrating these values. This method estimated experimental balloon volumes with considerable accuracy. Clinical evaluation revealed good correlation between DSA and conventional cine left ventriculography.

Angiography↗