Hyperinsulinemic response to oral glucose in obese patients with essential hypertension

Background and objectives: Hypertension is a common health problem. The prevalence of hypertension increases progressively with increasing Body Mass Index. The aim of this study is to investigate changes in blood pressure (BP), plasma glucose (PG) and insulin level after ingestion of oral glucose; and to assess the relation between insulin level and BP in obese and non-obese normo-tensive and hypertensive subjects. Materials and Methods: Seventy five g glucose dissolved in 250 ml of water was given orally to 20 fasting newly diagnosed untreated patients with essential hypertension and 15 normo-tenisve control subjects matched for age, gender and Body Mass Index (BMI). Smokers and subjects with diabetes, hyperlipidemia, cardiac or renal disease or those taking medications were excluded. Subjects were monitored for 2 hours.Half hourly BP, PG and insulin were measured. Results: Subjects were classified into obese (BMI≥ 30 Kg/m2) (11 patients, 8 normo-tensives) and nonobese (BMI< 30 Kg/m2) (9 patients, 7 normo-tensives). In obese hypertensive patients, insulin showed significant positive correlation with: systolic BP (SBP) (P=.04), diastolic BP (DBP) (P=.04) and mean BP(MBP)(P=.03). Obese hypertensive patients showed a significantly higher insulin response to oral glucose than obese normo-tensive subjects (P=.02).In obese and non-obese hypertensive patients glucose intake was associated with significant drop in DBP((P≤ .005), (P< .05)) and MBP ((P< .005), (P< .05)) respectively.Conclusions: In obese hypertensive patients, the hyperinsulinemic response to oral glucose and the positive correlation of insulin with BP suggest that insulin may be involved in development of essential hypertension especially in obese patients

Acute rheumatic fever in southern Saudi Arabia.

Forty six attacks of acute rheumatic fever (ARF) in forty patients were diagnosed between November 1987 and August 1995. Thirty four were initial attacks and 12 were recurrences. Arthritis was the commonest feature, 84.8%. Carditis occurred in 65.2% of the group, 67.6% of the initial attacks and 58.3% of the recurrences; however, the frequency of moderate/severe carditis was higher in recurrences, 25% versus 11.8%. Of those with carditis, mitral regurgitation occurred in 93.3%, aortic regurgitation in 16.7% and significant tricuspid regurgitation in 6.7%. Mitral stenosis was not encountered. No mortality occurred during ARF. Chorea, erythema marginatum and subcutaneous nodules were infrequent. These data are similar with those from a previous study which demonstrated the mild nature of ARF in Saudi Arabia, but showed higher frequency of carditis and suggested the frequency of carditis was not significantly higher during recurrences as compared to frequency of moderate/severe carditis.

Oral nitroglycerin in angina pectoris--evaluation of effect by computerized exercise testing using two different doses.

The antianginal effects of sustained-released oral nitroglycerin were evaluated in patients with chronic stable angina using a double-blind randomized protocol. Nineteen patients were inducted into the trial and 17 of these completed the study. Two doses of oral nitroglycerin were used; 2.6 mg and 6.5 mg given three times daily for a period of 2 weeks, the patients crossing over to the alternative dose at the end of each period. Evaluation of effect was carried out 2 hours after the morning dose using graded treadmill exercise testing with on-line computer analysis of the electrocardiogram (EKG) (CASE, Marquette Electronics, Inc.). Various exercise parameters were measured and the results compared to placebo values and between the two dosages. The aim was to demonstrate an antianginal effect and to look for a dose-response relationship and for attenuation of effect if any on continued administration. The mean +/- SEM exercise time on placebo was 6.7 +/- 0.6 min, increasing to 8.6 +/- 8 min (p less than 0.02) with 2.6 mg tds dosage and 8.4 +/- 0.7 min (p less than 0.01) with 6.5 mg tds of oral nitroglycerin. None of the other exercise-derived indices were altered significantly by oral nitroglycerin. Two patients were withdrawn because of severe headaches and both were receiving the higher dose. The data did not demonstrate any dose-response relationship but confirmed the anti-anginal efficacy of sustained action oral nitroglycerin. This efficacy did not show any significant attenuation of effect on continued administration, indicating a possible lack of development of tolerance.

Acute and sustained effects of isosorbide 5-mononitrate in stable angina pectoris.

Isosorbide 5-mononitrate (IS 5-MN) is an active metabolite of isosorbide dinitrate and is widely used as an antianginal agent. The acute and subacute (2 weeks) effects of IS 5-MN, 40 mg twice daily, were evaluated in 18 patients with stable angina pectoris using computerized exercise testing and a placebo-controlled, double-blind, randomized trial protocol. There were 2 phases of 2 weeks each in which patients received placebo or active IS 5-MN. Acute testing (8 patients) was performed 2 hours after the first dose and subacute testing 2 hours after the morning dose on day 14. Acute testing showed an increase in exercise time from a mean (+/- standard error of mean) of 8.2 +/- 0.6 minutes to 11.1 +/- 0.5 minutes (p less than 0.001) after a single dose of IS 5-MN. Time to 1 mm of ST depression increased significantly and peak exercise ST-segment depression decreased significantly. Rest and peak exercise heart rate increased significantly during acute testing with IS 5-MN; blood pressure did not change significantly. After 2 weeks of therapy, exercise time had not changed (9.9 +/- 0.6 with placebo to 9.7 +/- 0.6 minutes). The beneficial effects on ST-segment variables were sustained at 2 weeks. The data suggest that there is an attenuation of effect with respect to exercise time and sustained beneficial effect on the ST-segment variables. This may be a result of development of partial tolerance to IS 5-MN after 2 weeks of therapy.

Efficacy of once daily bisoprolol in stable angina pectoris: an objective comparison with atenolol and long term follow-up.

Bisoprolol is a new cardioselective beta-blocker with a long half-life. The efficacy of once daily bisoprolol (10 mg) and atenolol (100 mg) was assessed in 20 patients with stable angina using a placebo controlled double-blind randomized crossover protocol. Efficacy was assessed by computer assisted treadmill exercise testing with monitoring of leads CM5 and CC5, carried out 22-24 h after the last dose. The mean +/- SEM exercise time on placebo was 6.5 +/- 0.4 min increasing to 7.8 +/- 0.5 min on bisoprolol (P less than 0.001) and 8.6 +/- 0.6 mins on atenolol (P less than 0.001). The time to 1 mm ST depression in CM5 and CC5 was also prolonged significantly with both drugs. The mean basal resting heart rate of 84 +/- 4 bpm decreased to 63 +/- 2 bpm on bisoprolol (P less than 0.001) and 64 +/- 3 bpm on atenolol (P less than 0.001), with a significant decrease in the peak exercise heart rate seen with both drugs (P less than 0.001). The peak rate-pressure product was 175 +/- 8 after placebo, 146 +/- 7 (P less than 0.001) with bisoprolol and 149 +/- 5 (P less than 0.001) after atenolol. One patient was withdrawn because he suffered a myocardial infarction. Eighteen patients were prescribed bisoprolol 10 mg once a day for 6 weeks and an exercise test was performed at the end of this period. Bisoprolol retained its efficacy at the end of this period and was well tolerated.(ABSTRACT TRUNCATED AT 250 WORDS)

The effects of long-term physical training in patients with coronary heart disease.

A previous trial was completed in 24 patients with coronary heart disease, randomly assigned to a group who undertook a 6-month exercise training programme (5BX/XBX) and a control (no training) group. It was shown that the patients in the training group were able to achieve during exercise a higher heart rate at ST segment depression of 0.1 mV (HR/ST threshold) and that the patients in the control group showed a reduction in the threshold as well as symptomatic deterioration; the results indicated that the training programme had resulted in a reduction in the severity of myocardial ischaemia. In the present trial 9 patients of the previous training group were followed up to examine the effect of long-term maintenance training (up to 4.5 years). The same methods were used to examine the effect of maintenance training in a further group of 8 patients with coronary heart disease, 6 of whom were on beta-blocker therapy. By the end of the study, the heart rate achieved during exercise in the 17 patients was still significantly greater (P less than 0.0004) by 12.1 +/- 2.85 beats/min (mean +/- SEM) than that at the beginning of the trial; similar results were obtained in the 6 patients on beta-blocker therapy. Therefore a maintenance exercise training programme in patients with coronary heart disease can result in a sustained improvement in the form of a reduction in the severity of myocardial ischaemia, and this can occur in patients on beta-blocker therapy.

Assessment of aortocoronary bypass grafting using exercise ST segment/heart rate relation.

The maximal rate of progression of ST segment depression relative to increases in heart rate (maximal ST/HR slope) has recently been shown to be an accurate index of the presence and the severity of coronary heart disease in patients with angina. The value of this new exercise test was assessed in patients undergoing aortocoronary bypass. The maximal ST/HR slope and the results of coronary angiography were obtained in each of 46 patients before aortocoronary bypass surgery and in 26 of the 46 patients six months after the operation. At each stage of the investigation the maximal ST/HR slope detected without false results the absence and the number of significantly diseased vessels as shown by angiocardiography. As in previous findings the ranges of the maximal ST/HR slope showed no overlap between the four groups of patients: those with no significant disease and those with single, double, or triple vessel disease. In each of the 46 patients in whom the maximal ST/HR slope was determined before operation and three months afterwards the slope was lower after operation than before, indicating improvement. Follow up examinations showed that the maximal ST/HR slopes accurately detected the number of patent grafts used to bypass significantly diseased coronary arteries. Furthermore, the development of a significant narrowing or occlusion in any vein graft caused an increase in the maximal ST/HR slope which was equivalent to the value of single vessel disease. It is suggested that the maximal ST/HR slope may be used reliably in individual patients to indicate restoration of adequate blood supply to the myocardium after successfully aortorcoronary bypass surgery and the to detect in the period of six months after the operation the degree of severity of coronary heart disease whether it is caused by occlusion of the graft of significant disease of the coronary arteries.

Accurate detection of coronary heart disease by new exercise test.

The ability of a new exercise test accurately to detect the presence and severity of coronary heart disease has been examined in 206 patients with anginal pain, including patients on beta blockers or with concomitant cardiac lesions. From recordings of 13 electrocardiographic leads during exercise, the maximal rate of progression of ST segment depression relative to increased in heart rate (maximal ST/HR slope) was obtained and used as an index of myocardial ischaemia. The maximal ST/HR slope and results of coronary arteriography were independently obtained and the two sets of data compared the ranges of the maximal ST/HR slopes in the 38 patients with no significant disease, 49 with single vessel, 75 with double vessel, and 44 patients with triple vessel disease were different from each other and there was no overlap in the data between adjacent groups; there were no false positive, false negative, or indeterminate results. It is concluded that the maximal ST/HR slope can be used reliably to predict the presence of absence and severity of coronary heart disease in individual patients presenting with anginal pain in a hospital population.