Some notes on the history of rheumatic carditis

The history of rheumatic heart disease is briefly surveyed. Mitral regurgitation was recognized as the dominant lesion in acute carditis in the 1830s. This diagnosis fell out of favour in the early twentieth century. Also valvular lesions were then considered to be less important than myocardial disease as a cause of symptoms in chronic rheumatic heart disease. Successful mitral valvotomies in 1948 corrected this view. Mitral stenosis takes years to develop after acute valvulitis. Studies from the rheumatic fever research unit at Taplow showed absence of cardiac dilatation in first attacks of rheumatic carditis, poor prognosis with pericardial effusions, changing murmurs recorded by phonocardiography and cardiac output studies that justified treatment by bed rest. The multicentre trial of cortisone, adrenocorticotrophic hormone (ACTH) and salicylates showed no differences in development of chronic valvular disease. There is need for a more specific test for rheumatic activity than the erythrocyte sedimentation rate (ESR). It is hoped that a test can be developed to identify the minority of children at risk from rheumatic fever after a streptococcal throat infection in order to target antibiotic use. The declining prevalence of rheumatic fever is confined to the more prosperous countries. It remains common in the developing world. Penicillin prophylaxis is the sole advance in therapy. Better socio-economic environments are needed to reduce prevalence.

Some notes on the history of rheumatic carditis.

The history of rheumatic heart disease is briefly surveyed. Mitral regurgitation was recognized as the dominant lesion in acute carditis in the 1830s. This diagnosis fell out of favour in the early twentieth century. Also valvular lesions were then considered to be less important than myocardial disease as a cause of symptoms in chronic rheumatic heart disease. Successful mitral valvotomies in 1948 corrected this view. Mitral stenosis takes years to develop after acute valvulitis. Studies from the rheumatic fever research unit at Taplow showed absence of cardiac dilatation in first attacks of rheumatic carditis, poor prognosis with pericardial effusions, changing murmurs recorded by phonocardiography and cardiac output studies that justified treatment by bed rest. The multicentre trial of cortisone, adrenocorticotrophic hormone (ACTH) and salicylates showed no differences in development of chronic valvular disease. There is need for a more specific test for rheumatic activity than the erythrocyte sedimentation rate (ESR). It is hoped that a test can be developed to identify the minority of children at risk from rheumatic fever after a streptococcal throat infection in order to target antibiotic use. The declining prevalence of rheumatic fever is confined to the more prosperous countries. It remains common in the developing world. Penicillin prophylaxis is the sole advance in therapy. Better socio-economic environments are needed to reduce prevalence.

The value of exercise-induced U-wave inversion on ECG chest wall mapping in the identification of individual coronary arterial lesions.

Exercise-induced U-wave inversion on chest wall mapping was compared with coronary arteriographic findings in 160 consecutive patients who presented with chest pain suggestive of ischaemic heart disease. ECG recordings were made from 16 points on the chest wall before, during and after exercise. None of the 27 patients with normal coronary arteriograms developed U-wave inversion during or after exercise (specificity = 100%). In 21 (all males) of the 133 patients (15.8%) with significant coronary arterial lesions, U-wave inversion on exercise was noticed on different coronary artery territories on the chest wall map, and its localization was correlated with angiographic evidence of individual coronary arterial lesions (100% projection rate). In 9 patients (6.8%) this sign was observed in the absence of any ST segment changes or Q waves. Exercise-induced U-wave inversion was the sole ECG criterion reflecting a lesion of the left anterior descending artery in 12 cases (9%), of the circumflex in 6 cases (4.5%), and in only one case of right coronary artery disease. This sign was not detectable in the conventional V5 site in 9 cases (7.1%) with significant disease of the left anterior descending coronary artery. These nine patients showed U-wave inversion on other areas of the left anterior descending coronary artery territory on exercise. Exercise-induced U-wave inversion disappeared in all the ten patients who underwent coronary artery bypass graft surgery. It is suggested that exercise-induced U-wave inversion shown on chest wall mapping is a reliable indicator of coronary artery disease, which disappears after myocardial revascularization, and in addition, aids identification of individual coronary arterial lesions.

A dose response study with oral prenalterol in patients with chronic congestive cardiac failure.

Prenalterol is an orally active cardioselective beta agonist, with a long half-life. Previous studies have confirmed its inotropic activity following intravenous infusion in patients with heart failure. It has little chronotropic activity and no significant arrhythmogenicity. We have studied the response to sustained-release oral prenalterol given over four weeks at doses of 20, 40, 100, and 200 mg daily in 10 patients with New York Heart Association class II and III heart failure due to ischemic heart disease. All were in sinus rhythm and already receiving diuretics and digoxin. The drug was well tolerated and without side effects. Nine patients showed a dose-related improvement in their exercise tolerance as measured on the treadmill, up to a dose of 100 mg daily, with a significant increase in estimated oxygen uptake. There was a dose-related reduction in maximum heart rate, systolic blood pressure, and rate-pressure product during exercise, which is suggestive of a reduction in myocardial oxygen consumption. We conclude that prenalterol improves exercise tolerance without any significant cardiovascular or other side effects, and produces a clinically relevant and sustained improvement in patients with chronic heart failure. M-mode echocardiographic measurements of left ventricular dimension and function at rest did not show any change during the study.

Electrocardiographic chest wall mapping in the diagnosis of coronary artery disease.

Chest wall mapping of ST segment changes, inverted U waves, and Q waves using 16 electrocardiographic electrodes was performed at rest and during and after bicycle ergometry in 150 patients presenting with chest pain suggestive of angina. All patients underwent coronary angiography. The presence or absence of appreciable coronary artery disease (greater than or equal to 50% stenosis) was detected with a sensitivity of 98% and a specificity of 88%. The identification of lesions in individual coronary arteries was also possible with a sensitivity and specificity of 87% and 85% respectively for the territory of the left anterior descending and diagonal artery, 71% and 85% respectively for the right coronary artery, and 85% and 80% respectively for the circumflex artery. This test appears to be a reliable non-invasive screening method for selecting patients for angiography.

How disturbing are side effects of beta blockers.

Drug side effects are notoriously difficult to evaluate accurately. In this particular context there are further problems arising from the exclusion of many patients in some of the few published series of populations exposed to beta-blocking drugs. In some of these same series, placebo side effects appear to affect almost as many patients as the active drug. However, detailed breakdown of these side effects show significant differences in the actual complaints made by patients of each group. Apart from the well known major complications of beta-blocking drugs, the lesser but still disturbing ones to mention include generalized fatigue, muscle weakness, cold extremities, nightmares and impotence. A change of beta-blocking preparation or else lowering the dosage often ameliorates these problems.

Initial assessment of meptazinol in the treatment of the pain of myocardial infarction/unstable angina.

Meptazinol, a new analgesic agent, was used to treat chest pain in patients admitted to a coronary care unit with suspected myocardial infarction or unstable angina. A pilot study showed that meptazinol was effective in relieving pain in 15 out of 22 subjects. There were no adverse haemodynamic effects nor respiratory depression. Nausea and/or vomiting occurred with administration of the drug but as these symptoms may occur in patients with myocardial infarction who have not received any analgesia (Ingram et al., 1980), a cause and effect relationship cannot be inferred in this respect. The incidence of other side effects ascribed to meptazinol was low.

A comparison of the effects of the slow release formulations of metoprolol and oxprenolol in hypertension.

The therapeutic control of blood pressure and heart rate throughout the 24 hour period, was assessed in ten hypertensive patients, following the administration of placebo, conventional metoprolol 100 mg twelve hourly, and the slow release formulations of metoprolol (metoprolol S.A.) and oxprenolol (oxprenolol S.R.), given once daily. Good blood pressure control at rest was observed at two hours post dose following the three drug regimes. Analysis of blood pressure and heart rate values in response to exercise showed no difference between conventional and metoprolol S.A. at either two hours or 12/24 hours post dose. However, at 24 hours, metoprolol S.A. gave better clinical control of the systolic blood pressure and heart rate than oxprenolol S.R. with metoprolol inhibiting exercise induced tachycardia by 29% at 2 hours and 20% at 24 hours (oxprenolol 24% and 11% respectively). In this study, metoprolol S.A. was effective in the control of hypertension throughout the 24 hours period, both at rest and during exercise. The control at 24 hours by oxprenolol S.R. was poor and suggests that the present formulation should be reconsidered.

A clinical evaluation of sustained release metoprolol durules in the treatment of angina pectoris.

A clinical comparison of the sustained release form of metoprolol, consisting of a 200 mg metoprolol durule, with 100 mg conventional metoprolol twice daily, has been carried out to assess the therapeutic control of ten patients with stable angina pectoris. Objective measurements of heart rate, blood pressure, and ECG recordings were assessed during exercise on a bicycle ergometer. Ten patients completed the 8-week double-blind study. There were similar changes in heart rate and blood pressure at rest and during exercise, both at 2 h and at 12 and 24 h postdose. Although similar exercise tolerance was achieved on both regimes, there was significantly less ST-segment depression at 24 h post durule, in comparison with the 12 h post conventional metoprolol reading, suggesting that metoprolol durules produce a more effective reduction in the degree of myocardial ischemia.