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Dipyridamole was compared with exercise as a method of enhancing myocardial perfusion defects on thallium-201 scintiscans. Twenty patients with angina had scans after treadmill exercise to near the limit of effort tolerance, and again 4 h later in the redistribution phase. On a separate occasion the same patients had scans after intravenous dipyridamole 0.6 mg/kg. Fifteen of them were also investigated by coronary angiography. Exercise and drug-induced coronary dilatation caused segmental abnormalities of similar degree but the anatomical areas showing these perfusion defects correlated less well. Neither technique offered any clear advantage over the other in predicting the site of coronary stenosis, or in the quality of images obtained. Unwanted drug effects after intravenous dipyridamole were minor but included chest pain in four patients. Intravenous dipyridamole can reasonably be used instead of exercise for thallium-201 scintiscans. The technique will be of particular value when exercise testing is impracticable. [ABSTRACT FROM PUBLISHER]

A consecutive series of 559 hospital survivors of acute myocardial infarction aged less than 66 years were studied; 93 were designated prospectively as low-risk because they were suitable for early submaximal exercise testing and had none of the following clinical or exercise test ‘risk’: (1) angina for at least one month prior to infarction; (2) symptomatic ventricular arrhythmias, or (3) recurrent ischaemic pain, both after the first 24 h of infarction; (4) cardiac failure; (5) cardiomegaly; and (6) an abnormal exercise test (angina, ST-depression or poor blood pressure response). Altogether 301 patients were exercised; their mortality over a median follow-up of 2.4 years was 10.2%, versus 24.6% in the 258 patients not exercised (P=0.0005). Absence of clinical ‘risk factors’ alone, in the exercised patients, identified 156 with a mortality of 5.4% versus 15.6% in the 145 with at least one clinical ‘risk factor’ (P=0.004). The fully defined low-risk group comprised 93 of the former patients who had neither clinical nor exercise test ‘risk factors’. None of these patients died compared with 19 of those with at least one ‘risk factor’ (mortality=14.7% P=0.002). Their respective rates of non-fatal reinfarction were similar and never exceeded 5% per annum. Therefore, simple clinical and exercise test criteria can positively identify low-risk patients after infarction in whom secondary prevention may be inappropriate. [ABSTRACT FROM PUBLISHER]

The role of combined alpha and beta blockade as a means of limiting infarct size has been studied in a randomised controlled trial using labetalol. Only 166 of 630 (26%) consecutive patients admitted to a cardiac care unit with suspected myocardial infarction were deemed suitable for inclusion; most of the remainder had delayed admission to hospital, were over the age limit of 75, or had complications which precluded the use of labetalol. Those on active treatment received a loading dose followed by a slow intravenous infusion over six hours, and oral therapy for the subsequent five days. Doses were adjusted to maintain systolic pressure in the range 100 to 120 mmHg. The control group received only conventional therapy. Labetalol caused lowering of the blood pressure and heart rate during the phase of intravenous treatment, but little effect occurred subsequently because oral dosage was constrained by low systolic pressures. The group that received active treatment had significantly greater release of CKMB enzyme. Little difference was observed in R wave scores or ejection fraction. Only low doses of labetalol can be used for most patients with acute myocardial infarction. Labetalol cannot be recommended as routine treatment for normotensive patients admitted to hospital with suspected infarction. [ABSTRACT FROM PUBLISHER]

The current CAA requirements for routine electrocardiographs surveillance of flyers is outlined, and the need for care in recording techniques is stressed. Electrocardiographs should meet current standards and be in good repair. Exercise electrocardiograms should not be employed routinely, except possibly for flyers over 50 years of age engaged in single-pilot commercial operations. Exercise tests are of value for individuals with equivocal symptoms or equivocal repolarization changes but the results should be interpreted as far as possible on the basis of probability analysis: to report tests as ‘positive’ without amplification and with implication of high predictive accuracy is unsatisfactory. The techniques of effort testing should be standardized, should be conducted with scrupulous attention to detail, and should be performed only in centres specified and approved for the evaluation of pilots' fitness to fly. [ABSTRACT FROM PUBLISHER]

Aims: The second Randomized Intervention Treatment of Angina (RITA-2) trial compares an initial strategy of PTCA with continued medical management in patients with arteriographically proven coronary artery disease. This paper employs resource use data collected in the trial to compare the health service costs of the two strategies over 3 years follow-up., Methods and Results: 1018 patients were randomized, 504 to PTCA and 514 to continued medical management. Health service resource use data were collected prospectively on all patients. Hospital unit costs were estimated in collaboration with five U.K. centres. PTCA patients underwent more subsequent coronary arteriograms, but subsequent (non-randomized) PTCAs were more common in patients randomized to medical management (118 procedures in 102 patients) compared to those randomized to PTCA (73 procedures in 62 patients). The likelihood of undergoing CABG was similar in the two groups. The use of antianginal medications was higher in patients randomized to an initial strategy of medical management. There was an overall mean additional cost per patient over 3 years in patients randomized to PTCA of pound 2685 (95% CI pound 2074- pound 3322)., Conclusions: In RITA-2, the cost of an initial strategy of PTCA exceeded the cost of an initial strategy of medical management by 74% over 3 years., (Copyright 2002 The European Society of Cardiology. Published by Elsevier Science Ltd.)