Search PubMed⌕ Search

Biomedical subjects

K Tsuiki

Publications and source records attributed to K Tsuiki.

At least 91 records · Page 5Linked to original sources
PubMed1985

Detection of local abnormalities in ventricular activation sequence by body surface isochrone mapping in patients with previous myocardial infarction.

Body surface isochrone mapping was performed in 36 normal subjects and in 85 patients with previous myocardial infarction. Eighty-seven unipolar electrocardiograms distributed over the anterior chest and the back were recorded simultaneously. For each lead, activation time was measured as the time from the onset of QRS to the peak of the R wave. The lead points where R waves were not observed were designated the "no R wave area" (NR area). Isochrone maps of normal subjects had a consistent pattern, with isochrone lines extending from the right upper anterior chest to the left anterior chest and then to the back. NR area was small and was located only on the right upper chest or the upper back. On the isochrone maps of patients with myocardial infarction, abnormal findings were observed; NR area was found in 26 of 28 patients with anterior infarction on the upper to middle anterior chest, in 13 of 22 patients with inferior infarction on the lower chest, and in 24 of 25 patients with anterior and inferior infarction on the upper to lower anterior chest. Activation time was delayed near the NR area (peri-NR area delay) in 37 patients. In patients with apical infarction, an islandlike zone of delayed activation was typically found on the left precordium. These abnormal patterns are considered to indicate local abnormalities in the activation of infarcted myocardium; the NR area indicates dead unexcitable scar, and the peri-NR area delay and islandlike zone of delayed activation indicate partially infarcted myocardium of slow activation. Patients with NR area had greater degree of left ventricular asynergy and lower ejection fraction than those without.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1985

Diagnosis of coronary artery disease by body surface mapping--body surface distribution of exercise-induced ST changes in patients without myocardial infarction.

In 36 patients with effort angina pectoris without myocardial infarction, the sites of exercise-induced ST changes (depression and elevation) on the body surface were investigated. Exercise-induced ST depression was most often seen in left anterior chest leads. The body surface distribution of ST depression failed to identify the obstructed coronary artery. Exercise-induced myocardial ischemia was thought to extend to the greater part of the subendocardial region of the left ventricle. Exercise-induced ST elevation was mainly found on the upper right anterior chest. It has been suggested that these leads face the interior of the left ventricle and the observed ST elevation directly reflects subendocardial ischemia of the left ventricle. This data is important for evaluating ST changes in exercise electrocardiography.

Coronary Disease↗
PubMed1985

The clinical significance of exercise-induced ST-segment elevation in previous anterior myocardial infarction.

To investigate the mechanism of exercise-induced ST elevation in previous anterior myocardial infarction, exercise body surface mapping was performed on 22 patients with anterior myocardial infarction. ST elevation was compared with the findings of exercise radionuclide ventriculography and exercise thallium-201 myocardial perfusion imaging. ST-segment was quantified by the integral of ST-segment voltage. The maximal value of ST segment integral out of the 87 leads on the body surface was defined as ST max. The percent of change in ST max after exercise was closely correlated to the decrease in ejection fraction (r = 0.76). Furthermore, 9 of the 12 patients with increased ST max after exercise had exercise-induced regional wall motion abnormalities mainly in the apical and anterolateral segments, while other 10 patients without increased ST max did not (p less than 0.01). There was no difference in % change of ST max a) between anterior reversible defect (+) group and the (-) group; b) between inferior reversible defect (+) group and the (-) group; c) between single vessel (isolated left anterior descending artery stenosis) group and the multivessel group. This fact indicated that exercise-induced ST elevation did not result from the exercise-induced myocardial ischemia of the infarctional segment or the remote non-infarctional segment. We concluded that exercise-induced ST elevation in previous anterior myocardial infarction is mainly due to the aggravation of anterior wall motion abnormalities induced by exercise.

Adult↗
PubMed1985

[Functional reserve of the ischemic left ventricle with ventricular aneurysm to afterload stress: digital subtraction angiographic assessments].

Digital subtraction angiography (DSA) has been confirmed to be an accurate method for determining left ventricular function. It is a relatively non-invasive technique without inducing premature ventricular complexes. The response of left ventricular function to afterload stress was assessed using DSA for eight patients with old anterior myocardial infarction and ventricular aneurysm including that of the anterior wall (averaging 30.3 months after the acute episodes). Their ages ranged from 36 to 65 years and one patient was a woman. Prior to the investigation, we confirmed that a single DSA procedure did not alter left ventricular function in a pilot study of one patient (No. 8). After initial DSA in the basal state, methoxamine was infused intravenously (1 to 2 mg/min). When aortic systolic blood pressure increased by 30 to 50 mmHg, a second DSA was performed for each patient. Left ventricular volumes and ejection fractions were calculated by the area-length method, and regional wall motion was assessed by the visual method according to the AHA classification and the curvature radius of the apical ventricular aneurysm was calculated. Methoxamine induced neither acute heart failure nor angina pectoris in the present series. The heart rates decreased, and there were a significant increase in end-systolic volumes (p less than 0.05), end-systolic radii (p less than 0.05), and a significant decrease in ejection fractions (p less than 0.02) after methoxamine infusion. In 32 of 40 segments, regional wall motion was unchanged by methoxamine as assessed by the visual method; whereas, in the other eight, there was a deterioration.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1984

Determination of the left ventricular asynergic site by QRST isointegral mapping in patients with myocardial infarction.

QRST isointegral maps were made from 87 body surface ECGs in 41 patients with prior myocardial infarction. To evaluate the abnormalities of QRST isointegral maps, a deviation map was constructed from a deviation index, which expressed the deviation of the QRST time-integral value from the normal value at each lead point. Patients were divided into 3 groups according to the asynergic site on left ventriculograms: patients with anterior wall asynergy (n = 13), those with inferior wall asynergy (n = 13) and those with both anterior and inferior asynergies (n = 15). A consistent deviation map pattern was obtained in each group regardless of the QRS duration. Consequently, the deviation map was considered to be a practical method of identifying the asynergic site in patients with myocardial infarction, especially in those with intraventricular conduction disturbances. It is suggested that the deviation map can reveal abnormally altered intrinsic ventricular recovery properties resulting from a loss of the electromotive force of the infarcted myocardium.

Adult↗
PubMed1984

Attenuation of exercise-induced R wave increase after diltiazem in effort angina pectoris.

Body surface mapping was used to study the effects of diltiazem on exercise-induced QRS amplitude changes in 7 patients with stable effort angina pectoris. Body surface areas showing R or S amplitude changes (greater than 0.2 mV) after treadmill exercise were calculated. After the administration of 90 mg of diltiazem, the R increased area was significantly smaller than that without diltiazem (p less than 0.02), although the same workload was performed. It was suggested that diltiazem diminished the exercise-induced myocardial ischemia and this improvement of ischemia resulted in the reduction of the R increased area after exercise.

Adult↗
PubMed1983

Isointegral analysis of body surface maps for the assessment of location and size of myocardial infarction.

To estimate the location and size of myocardial infarction (MI), an isointegral mapping technique was adopted from among various body surface electrocardiographic mapping techniques. QRS isointegral and departure maps were made in 35 patients with MI. These patients were separated into 3 groups, based on the location of MI: anterior, inferior, and anterior plus inferior. The severity and location of MI were estimated by thallium-201 myocardial perfusion imaging and the degree of scintigraphic defect was represented by a defect score. The extent of MI was expected to be reflected on the QRS isointegral maps as a distribution of negative QRS complex time-integral values. However, the extent and the location of MI were hardly detectable by the original maps. A departure mapping technique was then devised to observe the distribution of departure index on the body surface. Particular attention was given to the area where the departure index was less than -2, and this area was expected to reflect the location and size of specific abnormality of isointegral map due to MI. There were strong correlations between departure area and defect score in the anterior and inferior MI cases (r = 0.88 and r = 0.79, respectively). However, patients with anterior MI plus inferior MI showed no such correlation. Q-wave mapping was compared with QRS isointegral mapping, and QRS isointegral mapping was found to be more accurate in the estimation of the location and size of MI than Q wave mapping. Thus, QRS isointegral mapping, especially departure mapping, is more useful and convenient for detecting the location and size of MI than methods such as isopotential and Q wave mapping.

Adult↗
PubMed1982

Treadmill stress test using body surface mapping in coronary artery disease--the clinical significance of ST depression.

In this study we assessed in 27 patients with coronary artery disease whether the size of the ST-depression area, which was measured by body surface maps recorded before and after treadmill exercise, could be a useful indicator for evaluating coronary artery disease (CAD) quantitatively. The patients were divided into 3 groups on the basis of the findings of the left ventriculograms: patients with anterior asynergy (n = 6), those with inferior asynergy (n = 6) and those with no asynergy (n = 15). Coronary arteriograms were evaluated according to Pujadas, and epsilon Grade, as an index of the severity of CAD, was developed by adding the grade numbers of the 4 main coronary stems (right coronary artery, main trunk of the left coronary artery, left anterior descending artery and left circumflex artery). Patients with inferior asynergy and with no asynergy have ST-depression areas in proportion to their epsilon Grade (r = 0.845, p less than 0.001), whereas none of the patients with anterior asynergy showed ST-depression areas regardless of their epsilon Grade. Of 6 patients who had anterior asynergy, 5 (83%) had pathologic Q waves in the left anterior chest leads. These findings emphasize the clinical value of the ST-depression are for the quantitative and non-invasive diagnosis of CAD, especially in patients without pathologic Q waves in the left anterior chest leads.

Adult↗
PubMed1982

The beneficial effect of diltiazem on exercise-induced ST depression, measured by body surface mapping, in stable effort angina pectoris.

The effect of diltiazem, a calcium antagonist, was examined in eight male patients with stable effort angina pectoris by means of multistage treadmill testing using body surface mapping. The area and severity of exercise-induced ST depression after 90 mg of diltiazem administered orally three hours before exercise were compared with those without diltiazem. Although the same workload was performed, the area and severity of exercise-induced ST depression were significantly diminished (P less than 0.005) after diltiazem. The reproducibility of these observations was confirmed in two of the eight patients studied and in three other patients. Because exercise-induced ST depression in patients with coronary artery disease is generally believed to reflect myocardial ischemia, our results provide objective evidence that diltiazem is able to reduce the exercise-induced myocardial ischemia in effort angina pectoris.

Aged↗