Biomedical subjects

A D Harrower

Publications and source records attributed to A D Harrower.

59 records · Page 4Linked to original sources

PubMedDate not supplied

The value of continuous ECG monitoring during treatment of diabetic ketoacidosis. A computer study.

In order to confirm or refute the previously held view that electrocardiographic (ECG) abnormalities are frequent in diabetic ketoacidosis, we have undertaken continuous ECG monitoring for 24 h, with subsequent computer analysis, in 14 diabetic patients admitted with severe ketoacidosis. There was a steady fall in heart rate during the 24-h except in 3 severely dehydrated patients. Depression of the ST-segment was minimal and ST-segment height correlated significantly with heart rate, whereas no consistent relationship was found between T-wave amplitude and either heart rate or plasma potassium. Two patients developed short periods of supraventricular ectopic beats. Although ECG monitoring has been claimed to be a useful aid in the management of diabetic ketoacidosis, this study clearly demonstrates that significant ECG changes are rare and ECG monitoring thereafter adds little to careful clinical observation and regular biochemical assessment.

Adolescent↗

PubMedDate not supplied

Assessment of myocardial perfusion during cold stress using thallium-201 scintigraphy in diabetic patients with abnormal changes in left ventricular function during cold stress.

Eleven type-I (insulin-dependent) diabetic patients with abnormal changes in left ventricular function in response to cold stress (CS) were investigated to try and determine the cause of these abnormal responses. Resting M-mode echocardiography demonstrated that all 11 patients had normal left ventricular dimensions and wall motion, thereby excluding overt cardiomyopathy. Thallium-201 scintigraphy was used to assess myocardial perfusion during CS and eight patients were found to have perfusion defects during stress which persisted in four. It is possible that CS unmasks evidence of myocardial ischemia but it is also possible that the abnormal responses to CS reflect altered vasomotor reactivity in the diabetic patient, producing coronary spasm. Left ventricular function may be influenced by many factors in diabetes and an abnormal CS test may not necessarily indicate structural disease. Such tests, however, may help in the further understanding of the pathophysiology of heart disease in diabetes.

Adult↗

PubMedDate not supplied

Cardiac function during stress testing in long-standing insulin-dependent diabetics.

Four dynamic tests of cardiac function were compared in a group of 13 long-standing insulin-dependent diabetics who had no clinical evidence of cardio-respiratory disease. One patient developed abnormal features during 24 hour ambulatory electrocardiograms while all 13 patients had normal exercise electrocardiograms. The change in left ventricular ejection fraction during dynamic supine exercise as measured by gated blood-pool scintigraphy was not significantly different from control subjects (p less than 0.1) while during cold stimulation testing the change in left ventricular ejection fraction in the diabetics was highly significantly different from the control subjects (p less than 0.01). Five of the patients had one or more abnormal tests of autonomic function. The cold stimulation test may be a sensitive index of cardiac dysfunction in diabetics but as the mechanism is unclear alternative explanations are possible. While the etiology of heart disease in such patients is uncertain it is likely to be multifactorial and this test may prove useful in investigating the natural history and pathogenesis of cardiac disease in diabetics.

Adolescent↗

PubMedDate not supplied

Comparison of efficacy, secondary failure rate, and complications of sulfonylureas.

The data from three clinical trials are presented, comparing the efficacy of different sulfonylureas in the treatment of type II diabetes. In a multicenter study, gliclazide improved control in 49% of patients who had failed on other drugs. When five groups of type II diabetic patients were treated concurrently with five randomly allocated different sulfonylureas over 1 year, the percentage of patients achieving normal HbA1 levels was best with gliclazide (80%) and glibenclamide (74%), when compared with chlorpropamide (17%), glipizide (40%), and gliquidone (40%). Secondary failure rate over 5 years was assessed in 248 type II diabetic patients randomly allocated to three different sulfonylureas and found to be lowest with gliclazide (7%) compared with glibenclamide (17.9%): p < 0.1) and glipizide (25.6%: p < 0.005). The incidence of hypoglycemia was significantly higher with glibenclamide than with gliclazide (p < 0.05). The differences in efficacy and secondary failure rate between sulfonylureas may be related to the mechanism of insulin release from the beta-cell and the more physiological action of gliclazide could partly explain this. These trials suggest that gliclazide is a potent sulfonylurea with a low rate of secondary failure and a low incidence of side effects and may be a better choice in long-term sulfonylurea therapy.

Clinical Trials as Topic↗

PubMedDate not supplied

Effect of indapamide on blood pressure and glucose tolerance in non-insulin-dependent diabetes.

Ten hypertensive non-insulin-dependent diabetic patients were treated with the antihypertensive drug indapamide to assess its effect on glucose tolerance over 1 year. Both systolic and diastolic blood pressures fell significantly (p less than 0.001) over the first month of treatment, and no change in plasma glucose or plasma insulin levels during an oral glucose tolerance test occurred at any time. Indapamide is an effective antihypertensive drug and, in contrast to thiazide diuretics, has no adverse effect on glucose tolerance in non-insulin-dependent diabetic patients.

Adult↗