The incidence of ventricular arrhythmias after myocardial infarction has been compared in a controlled study of procainamide, mexiletine, and placebo. Sixty male patients who has sustained a myocardial infarction and had received lignocaine for ventricular tachycardia or ventricular ectopic beats which were R-on-T, multiform, or close-coupled took part. The efficacy of the drugs was evaluated by continuous 24-hour recordings of the electrocardiogram on the 4th and 10th days after admission to the study. Procainamide was given as 500 mg. 4-hourly and mexiletine as 250 mg. 8-hourly with corresponding placebo regimens for 12 days. 77% of patients receiving placebo showed serious ventricular rhythm disorders compared with 33% receiving antiarrhythmic therapy (p smaller than 0.05). Although only 35% of patients receiving procainamide achieved accepted therapeutic plasma concentrations compared with 95% of those receiving mexiletine, both drugs were equally effective antiarrhythmically. The only major adverse effect of therapy noted was development of a positive antinuclear factor in a procainamide-treated patient. These results demonstrate the efficacy of oral antiarrhythmic agents in the management of ventricular arrhythmias after acute myocardial infarction. Mexiletine has the advantage of less frequent administration and lower toxicity.

The cardiovascular effects of hypoglycaemia, with and without beta-blockade, were compared in fourteen healthy men. Eight received insulin alone, and eight, including two of the original insulin-only group, were given propranolol and insulin. In the insulin-group the period of hypoglycaemia was associated with an increase in heart-rate and a fall in diastolic blood-pressure. In the propranolol-insulin group there was a significant fall in heart-rate in most subjects and an increase in diastolic pressure. Typical S-T/T changes occurred in the insulin-group but in none of the propranolol-insulin group. Hypertension in diabetics prone to hypoglycaemia attacks should not be treated with beta-blockers because these drugs may cause a sharp rise in blood-pressure in such patients.

230 Canadian steelworkers with hypertension took part in a randomised trial to see if compliance with antihypertensive drug regimens could be improved. For care and follow-up these men were randomly allocated to see either their own family doctors outside working-hours or industrial physicians during work shifts; the same men were randomly allocated to receive or not receive an educational programme aimed at instructing them about hypertension and its treatment. Surprisingly, the convenience of follow-up at work had no effect upon these men's compliance with antihypertensive drug regimens. Similarly, although men receiving health education learned a lot about hypertension, they were not more likely to take their medicine.

Conventional methods of monitoring arrhythmias impose heavy demands on staff and are unreliable. On-line arrhythmia computers have been developed to overcome these problems, but there has been no critical evaluation of the functioning of such a system in a clinical setting. A comparison was made of the efficacy of two methods of monitoring in detecting arrhythmias in sixty-four patients in a coronary-care unit. Half the patients were monitored by a commercially available arrhythmia computer; the other half were monitored by conventional means with a rate-triggered alarm system. More than 99 percent of episodes of potentially serious ventricular arrhythmias were detected by the computer; 95 percent of patients with these arrhythmias were treated immediately. In those monitored by conventional means, a large proporation of such arrhythmias were unrecognised: only 17 percent of affected patients received immediate antiarrhythmic therapy. In 30 percent, treatment was delayed for several hours, and none was given in 52 percent. False alarms occurred with both systems but were more readily recognised as such in the computer-monitored patients. It is concluded that an arrhythmia computer improves the standards of arrhythmia detection, leads to quicker institution of treatment, and diminishes the demand on skilled staff.

36 G of wheat fibre, pectin, or guar gum was given over 2-week periods to healthy volunteers taking normal diet. Mean serum-cholesterol levels fell significantly while the volunteers were taking guar and pectin by 36-3 and 29-2 mg, per 100. respectively, but rose slightly after wheat fibre by 6-7, mg per 100., Attention should be focused on fruit and vegetable gels rather than wheat fibre in the search of natural hypocholesterolaemic agents.

The blood-pressure responses to carrying a 15 kg. weight in a shoppong basket, and in a rucksack on the back, were compared in 13 ambulant male patients who were convalescing from an uncomplicated myocardial infarction. In 8 of the patients a sustained-handgrip test was also performed. Carrying the weight in the hand produced a distinct increase in blood-pressure, which did not occur when the weight was carried on the back. There was also a significant increase in blood-pressure during sustained handgrip. In view of the lack of symptoms with these circulatory changes, it is concluded that more specific advice about the possible dangers of sustained static exercise should be given to patients recovering from myocardial infarction.

Urinary calcium and magnesium excretion was measured in two groups of soldiers leaving the temperate climate of the united Kingdom for service in the Persian Gulf. In one group urinary calcium levels and magnesium/calcium ratios were similar, ten days after arrival in the Gulf during the "cold season", to those found in the U.K. The other group went to the Gulf in the "hot season", and calcium excretion rose immediately to levels comparable with those found in the first group after eight months. Mg/Ca ratios fell to levels seen in stonformers, and 2 of 91 soldiers followed up for three years have had urinary calculi. Increased exposure to sunlight seems to be the most likely cause of the hypercalciuria.

10 percent glycerol was given for 6 days to 30 patients who had had acute ischaemic cerebral infarction, and the results were compared with those obtained after treating 31 similar patients with dexamethasone (16 mg. per 24 hours for 6 days). 1 patient treated with glycerol died of haemoglobinuria and acute renal failure. 6 patients treated with dexamethasone died--3 from cerebral oedema and 3 from non-neurological complications (pulmonary embolism, myocardial infarction, and aspiration pneumonia). Improvement was significantly greater in the glycerol group after 8 and 15 days. No improvement was noted using either glycerol or dexamethasone in 7 patients with spontaneous intracerebral haemorrhage.

The distribution of pectoral (external mammary) nodes identified during the operation and removed with the axillary tail of the breast was studied in 45 patients treated by simple (total) mastectomy. Up to 13 nodes may lie within the axillary tail, and these are continuous with the pectoral nodes. Lymph-nodes were identified in 90 percent of patients treated by simple (total) mastectomy without dissection of the axilla.