Search PubMed⌕ Search

Biomedical subjects

K Haze

Publications and source records attributed to K Haze.

At least 127 records · Page 7Linked to original sources
PubMed1986

Evaluation of clinical factors involved in onset of myocardial infarction.

In order to discuss the mechanism of onset in myocardial infarction (MI), clinical cases were reviewed and various clinical findings were analyzed according to the premise that the onset of MI requires both a predisposition and a trigger. The majority of subjects did present conditions that constituted predispositions for MI, including a history of angina pectoris (especially unstable angina), poor therapeutic results for angina pectoris, organic stenosis of the coronary artery, life changes, and overwork. Patients with multiple factors tended to develop MI without a definite trigger, i.e., onset during sleep or rest whereas, in patients with fewer predisposing factors, it was obvious effort, excitation or stress that triggered MI. However, not a few of the patients presented with no organic stenosis of the coronary artery or no history of angina pectoris. There were patients without ST segment elevation at onset of MI, and patients in whom ST elevation was recorded after onset. These findings suggest the existence of mechanisms other than coronary occlusion in onset of MI. Occlusion of the coronary artery distributed to the infarct region occurred frequently among patients with delayed CPK efflux as well as prolonged chest pain and ST segment elevation. These lines of evidence suggest extension of infarction due to secondary coronary occlusion.

Angina Pectoris↗
PubMed1986

Current status and problems in long-term management of patients undergoing coronary artery bypass surgery in Japan.

We studied 272 patients undergoing coronary artery bypass surgery (CABS) to clarify the long-term effects of CABS and to identify problems in long-term management. Data on patients' pre and postoperative medical status were obtained from hospital files. A specially designed questionnaire was sent to all patients to assess residual angina, return to work, non-work physical activity and improvement in the quality of life after a mean follow-up of 29 months. Multivessel disease accounted for 89% of all patients and complete revascularization was achieved in 55%. A total of 131 events of complications associated with CABS occurred in 112 patients; post-transfusion hepatitis was the most frequent complication (26%). Graft patency rate was 89% at the time of hospital discharge. Bypass grafts were patent in 95% of 243 grafts which were restudied at a mean period of 19 months after the first study. There was no significant difference in the patency rate between patients with well controlled, poorly controlled or discontinued anticoagulant therapy. Patients who were relieved from angina, returned to gainful work and had no limitation in non-work physical activity accounted for 74%, 79% and 73%, respectively. By subjective assessment, the quality of life improved in 76% of all patients. Objectively, contributing factors preventing improvement in the life quality were residual angina and post-transfusion hepatitis. There were 13 patients who were readmitted because of cardiac events. Three patients died from these events including two from sudden death during follow-up. We conclude that the beneficial effects of CABS are actually attainable.(ABSTRACT TRUNCATED AT 250 WORDS)

Activities of Daily Living↗
PubMed1986

Age-related changes of clinical features and prevalences of coronary risk factors in Japanese patients with vasospastic angina.

From among 899 consecutive patients who underwent their first coronary arteriography, we selected 147 pts with vasospastic angina (VA) and 356 pts with classic angina (CA) and divided them into three different age groups: -49 years old, 50 to 59, and 60-. In these 899 pts, incidences of VA showed no increase with aging. Prevalence of coronary risk factors in CA, such as diabetes, hypercholesterolemia, hypertension, and obesity, was higher than in VA, although prevalence of smoking in CA was lower than in VA. In VA, we found an age-related increase in the incidence of smoking only, in contrast to the other four risk factors. The VA showed no age-related increase in the incidence of complication of fixed coronary stenosis. These findings suggest that aging and atherosclerosis might not play a major role in pathogenesis of VA, although the mere presence of atherosclerosis irrespective of its severity could interact with local susceptibility to spasm, leading to coronary vasospasm.

Adult↗
PubMed1985

Poor responsiveness of heart rate to treadmill exercise in vasospastic angina.

Heart rate response to submaximal graded treadmill exercise was measured in 45 patients with vasospastic angina, 31 with effort angina, and 40 normal controls. There was no difference of resting heart rate among the three groups. Vasospastic angina showed significantly poor responsiveness of heart rate to exercise at every stage: stage 1, 2.5 km/h (10%), stage 3, 4.5 km/h (10%), stage 5, 5.5 km/h (14%), stage 7, 5.5 km/h (22%), when compared with those in normal controls. The effort angina group also showed lower heart rates at stages 3 and 5 than those in control subjects, although their heart rate at stage 1 was not different from that in normals. When abnormal response suggesting vasospastic angina was defined as heart rate at each stage lower than values of mean heart rate +/- 1 SD in normal controls, positive test results were obtained in 15 of 45 patients (33%). The use of heart rate criteria in addition to ischemic criteria raises sensitivity from 27 to 51% (p less than 0.02).

Adult↗
PubMed1985

Abnormal heart rate control in vasospastic angina: effects of calcium antagonists.

We examined the effects of administration of calcium antagonists on the heart rate response to treadmill exercise in 11 patients with vasospastic angina and 8 healthy young volunteers. The exercise test was performed by walking on a treadmill at a constant speed and grade according to a scheme of pseudo-randomized sequence for 19 min. The dynamic property of heart rate response to exercise was evaluated by using a frequency analytic procedure. The exercise test was also studied in 21 age-matched normal controls without drug administration. Administration of calcium antagonists revealed no significant effects on heart rate and blood pressure at rest in young healthy subjects or in patients with vasospastic angina. Young volunteers showed the same normal properties of heart rate response to exercise before and after calcium antagonists. Vasospastic angina showed abnormal heart rate response to exercise and revealed characteristically different transfer function from that in normal controls. These characteristics were not affected by treatment with calcium antagonists except for a slight, uniform decrease of gain of the system over the whole frequency range. Accordingly, the present exercise test can feasibly be used in the diagnosis and management of vasospastic angina even when calcium antagonists are administered to the patients.

Administration, Oral↗
PubMed1985

Classification of non-Q-wave myocardial infarction according to electrocardiographic changes.

The characteristics of 93 patients in whom electrocardiographic recordings were obtained within 12 hours of the onset of non-Q-wave myocardial infarction were studied. Patients were divided into the three groups according to what electrocardiographic changes were seen. Forty nine patients had ST segment depression, 35 had ST segment elevation, and nine had T wave changes. Patients with ST segment depression had a higher rate of pump failure and multivessel disease than the other two groups. There were no significant differences in peak serum creatine kinase activity among the three groups. Twelve of 13 patients who died of non-Q-wave myocardial infarction in hospital had ST segment depression. Furthermore nine of them had attacks of non-Q-wave myocardial infarction with severe ST segment depression in many leads. At necropsy five of six patients who had shown severe ST segment depressions in many leads at the onset of non-Q-wave myocardial infarction were found to have circumferential subendocardial lesions with triple vessel disease. This study suggests there are electrocardiographic subtypes of non-Q-wave myocardial infarction that are associated with specific patient characteristics.

Aged↗
PubMed1985

Effects of right ventricular ischemia on left ventricular geometry and the end-diastolic pressure-volume relationship in the dog.

We studied the effects of right ventricular ischemia on left ventricular three-dimensional geometry and the end-diastolic pressure-volume relationship in 16 open-chest dogs before and after pericardiectomy. Left ventricular volume was calculated from three internal dimensions measured with ultrasonic crystals. In one group of eight dogs, right coronary artery (RCA) occlusion for 2 min with the pericardium intact reduced aortic flow by 24 +/- 9% (p less than .001) and septal-lateral dimension by 8 +/- 5% (p less than .01), without changing anterior-posterior and apical-basal dimensions. However, parameters of left ventricular systolic function (aortic flow, left ventricular systolic pressure, peak dP/dt, and mean percent systolic shortening) were similar to those observed at a comparable level of left ventricular end-diastolic volume during inferior vena caval occlusion. In the other group of eight dogs, during RCA occlusion before pericardiectomy the left ventricular end-diastolic pressure-volume relationship determined during rapid blood transfusion shifted leftward and upward significantly from the preocclusion relationship. After pericardiectomy, RCA occlusion caused less significant changes in aortic flow and septal-lateral dimension as well as in the left ventricular end-diastolic pressure-volume relationship. We concluded that right ventricular ischemia causes a leftward shift of the interventricular septum in end-diastole and an alteration of the left ventricular end-diastolic pressure-volume relationship without changing left ventricular myocardial performance. These changes are enhanced by the intact pericardium.

Animals↗
PubMed1985

Clinical characteristics of coronary artery spasm: electrocardiographic, hemodynamic and arteriographic assessment.

We studied the clinical characteristics of 153 patients with angina pectoris associated with coronary artery spasm (CAS). The study was designed to investigate the relationship of CAS to ST segment deviation and to the site of fixed stenosis, and hemodynamic alteration during a spastic event. Analysis of coronary arteriograms and multilead electrocardiograms obtained simultaneously from 170 events of CAS by the use of radioluscent carbon-fiber electrodes resulted in 58 events with ST elevation which were related to total occlusion of major coronary arteries due to CAS; another 54 events with ST depression, in which the affected coronary arteries demonstrated severe but incomplete occlusion, or total occlusion but were visualized via collateral vessels; and remaining 58 events without ST deviation showing mild occlusion. The results indicate a close correlation between magnitude of CAS and ST segment deviation. CAS occurred at the site of pre-existing fixed stenosis including minor plaque defect in 133 patients and at apparently normal site in 20 patients. In the former group, only four patients had triple vessel disease, while 95 had nonsignificant fixed lesion. In the latter group, 10 patients had minor lesion distant from the site of CAS. Thus, CAS is closely related to fixed stenosis, which may have but a limited role as a cause of CAS. Hemodynamic measurements during spastic events were obtained from 49 patients including 41 events with spasm of the left anterior descending artery (LAD) and 21 events with spasm of the right coronary artery (RCA). The onset of an increase in left ventricular (LV) filling pressure and a reduction in LV dP/dt preceded ST segment deviation in all events. The first hemodynamic variable manifested in the spastic event was the reduction of LV contraction dP/dt in the majority of patients. The increase of LV filling pressure was greater in LAD spasm than RCA spasm (11 +/- 6 mmHg vs 7 +/- 4 mmHg, P less than 0.0125) and in events with ST elevation than with ST depression (11 +/- 5 mmHg vs 6 +/- 5 mmHg, p less than 0.001). Right ventricular functional impairment was mild in most patients during CAS. The study indicates that mechanical impairment precedes electrical impairment during CAS and that LAD spasm with ST elevation represents the most severe LV dysfunction.

Adult↗
PubMed1984

Abnormal heart rate response to exercise in vasospastic angina: pathophysiologic mechanism in the provocation of coronary spasm.

To examine the alteration in control function of the heart, which may account for the pathophysiologic condition precipitating coronary arterial spasm, the dynamic property of heart rate response to exercise in vasospastic angina was evaluated by using our previously developed frequency analytic procedure. We studied 21 patients with vasospastic angina, divided into two groups (active angina and inactive angina) and 12 normal control subjects. When compared with the transfer function of the heart rate control system in normal control subjects, the transfer function in patients with active vasospastic angina showed moderately lower gain, especially in the middle frequency range, and significantly delayed phase angle over the whole frequency range, especially in the middle and high frequency ranges. These abnormalities were not observed in inactive vasospastic angina. The present exercise test to detect abnormal heart rate control can feasibly be used in the detection and management of vasospastic angina.

Adult↗
PubMed1984

Usefulness and limitations of vasodilator therapy in the treatment of pump failure complicated by acute myocardial infarction.

The factors associated with the development of pump failure in patients with acute myocardial infarction (MI) were studied in 475 patients admitted to our coronary care unit (CCU) and a clinical and hemodynamic re-evaluation of vasodilator and catecholamine therapy was carried out in patients with pump failure. The severity of pump failure as represented by Killip's classification was closely related to left ventricular (LV) dysfunction as judged by LV ejection fraction, number of previous MIs and peak creatinine phosphokinase (CPK) value, and the severity of coronary atherosclerotic lesions as assessed by coronary arteriography. Retrospective hemodynamic analysis of vasodilator therapy (intravenous nitroglycerin, nitroprusside and phentolamine) in 94 patients with pump failure revealed that a significant decrease in pulmonary capillary wedge pressure (PCW) with no significant change in cardiac index (CI) resulted in a clinical improvement in pulmonary congestion in Forrester's hemodynamic subset 2. However, in patients in subsets 3 and 4, the slight increase in CI induced by vasodilator therapy was not enough to restore normal systemic perfusion in spite of a significant decrease in PCW and total systemic resistance; catecholamine was far more effective in increasing CI. Thus, the major indication for vasodilator therapy is in patients of subset 2, while combined use with catecholamine is preferable in those with low cardiac output.

Aged↗
PubMed1984

Effectiveness and limitation of the current coronary care unit in treatment of patients with complications following acute myocardial infarction.

For an appraisal of effectiveness and limitation of the current coronary care unit (CCU) in treatment of patients with complications following acute myocardial infarction (MI), consecutive 557 patients hospitalized to our CCU during five years were studied. In order to assess the severity of complicating pump failure, patients were divided into four classes according to Killip's classification. Number of patients, total mortality (%) and mortality due to pump failure (%) were as follows; 333 (6%, 2%) in class I, 118 (17%, 8%) in class II, 42 (19%, 17%) in class III and 55 (84%, 80%) in class IV. Warning arrhythmias, cardiac rupture and interventricular septal perforation complicated in 184 patients, 11 and 10, respectively, and mortality due to these complications was 2%, 91% and 84% in the order. Right ventricular infarction complicated in 54 patients, but only one patient died from right heart failure. Post-MI angina manifested in 156 patients and six of them died postoperatively. Our data indicate that improvement in mortality due to pulmonary edema and arrhythmias and reduction in incidence of cardiac rupture are evident effectiveness of the CCU, and that there is no improvement in survival rate of patients with cardiogenic shock even under the use of newly introduced vasodilator and catecholamine therapy or intraaortic balloon pumping.

Angina Pectoris↗
PubMed1984

Effects of isosorbide dinitrate spray on central hemodynamics. Comparison with sublingual glyceryl trinitrate and isosorbide dinitrate.

Effects of isosorbide dinitrate (ISDN) spray (Iso Mack Spray) on central hemodynamics were determined in comparison to sublingual glyceryl trinitrate (nitroglycerin) and ISDN, paying particular attention to their onset and duration of action. In nine patients with uncomplicated acute myocardial infarction, ISDN spray (2 sprays, 2.5 mg) glyceryl trinitrate (TNG, 0.3 mg) and ordinary ISDN tablet (5 mg) were administered by the single-blind crossover method under hemodynamic monitoring with a Swan-Ganz catheter. Systolic pulmonary artery pressure (s-PA), systolic pressure (s-BP) and heart rate were measured every minute for 10 min, every 5 min for the subsequent 20 min and thereafter every 15 to 30 min up to 120 min. Using s-PA as a measure of nitrate action, the onset and duration of action as well as the magnitude of change was compared among the three drugs. ISDN spray had a quick onset of action (2.67 +/- 2.4 min, mean +/- SD) comparable to that of TNG (2.67 +/- 1.00 min), while ISDN spray had a long duration of action (57.4 +/- 42.1 min), which was comparable to that of sublingual ISDN (85.6 +/- 39.5 min, ns) and was significantly longer than that of TNG (11.4 +/- 6.4 min, p less than 0.05). ISDN spray (2.5 mg) showed the same hemodynamic changes as were induced by 0.3 mg TNG or 5 mg ISDN. The results of this study led us to conclude that ISDN spray is a useful agent which induces the abortion of anginal attacks by its quick onset and long duration of action.

Administration, Topical↗