[Treatment of hypertrophic cardiomyopathy]. / Behandling af hypertrofisk kardiomyopati.

The medical management of hypertrophic cardiomyopathy is reviewed. Four cases of hypertrophic cardiomyopathy are presented, and serve to describe the currently available invasive treatment modalities, i.e. septal myectomy, dual chamber pacing, cardioverter defibrillator implantation and heart transplantation. These different invasive treatments all seem to be symptomatically effective in carefully selected patients, but studies of prognostic effects are not available. Finally, new experimental procedures are presented.

[Alcohol and the heart]. / Alkohol og hjertet.

Structural cardiac morphological changes develop in a considerable number of chronic alcoholics, and preclinical cardiomyopathy is frequent especially among those with alcoholic liver disease. Alcohol exerts an acute albeit transient toxic effect on cardiac performance resulting in an impaired contraction of the myocardium. The effect is dose-dependent at rest, whereas compensatory mechanisms counterbalance the alcohol-induced changes during exercise. Similar cardiovascular reactions are recorded in patients with coronary artery disease, in whom the vasodilatory effect is measurable. In predisposed individuals heavy alcohol intake may induce atrial fibrillation or even malignant arrhythmias. Arterial hypertension is often found during the period following an alcohol excess, but this effect seems to be reversible. Alcohol intake inhibits aggregation of blood platelets and induces an increase in the level of high density lipoprotein cholesterol inhibiting atherogenesis. These mechanisms may well be dominant factors in the interpretation of the obvious protective effect of alcohol as seen in the U- or J-shaped relation between daily alcohol consumption and rate of survival. This relation clearly demonstrates a lower mortality among people consuming one to two drinks per day compared with both those who drink more and with alcohol abstainers, justifying that these people should continue their drinking habits unless they have diseases contraindicating alcohol consumption or have an increased risk of developing chronic alcoholism.

[Reproducibility of electrocardiographic interpretation in patients with suspected myocardial infarction. A controlled study of the effect of a training trial]. / Reproducerbarheden af bedømmelse af elektrokardiogrammer hos patienter mistaenkt for akut myokardieinfarkt. En kontrolleret undersøgelse af effekten af et undervisiningsforsøg.

We examined the effect of a training programme to reduce interobserver variation in interpretation of electrocardiography in suspected myocardial infarction. Sixteen doctors with 6-24 months of clinical training in internal medicine read serial electrocardiographic recordings in 107 patients and assessed whether signs indicative of acute myocardial infarction were present. There was disagreement in approximately 70% of cases. Eight of the doctors were randomly allocated to attend an eight hour long intensive course on interpretation of electrocardiography in myocardial infarction. The remaining eight participants were allocated to a control group, received no training, and were not told about the subject of the study. All the doctors then reviewed another series of electrocardiographic recordings. No difference was found in the level of agreement within the two groups before and after the training programme, or between the two groups before and after the training. The raters' ability to discriminate between electrocardiograms with a high and low indication of infarction remained unaffected. We conclude that the training programme did not increase agreement regarding the interpretation of electrocardiographic data in suspected myocardial infarction. Our results suggest that the diagnostic approach of physicians is established at a very early stage in their clinical training. The effect of training programmes should be evaluated by the use of randomized clinical studies.

[201-thallium myocardial scintigraphy before and after percutaneous transluminal coronary angioplasty]. / 201thallium myokardieskintigrafi før og efter perkutan transluminal koronar angioplastik.

We describe our experience from the first 30 patients treated with percutaneous transluminal coronary angioplasty (PTCA) in the Cardiologic Department P, Gentofte Hospital. The main purpose was to evaluate the value of thallium scintigraphy performed before and three months after PTCA. After PTCA, 23 (77%) had no angina and 22 (73%) had normal exercise-ECG. On the basis of the scintigraphies before PTCA, the patients were divided into two groups: In group 1, five had normal scintigraphy and 14 reversible perfusion defects only. In group 2, all 11 patients had both persistent and reversible defects. In patients without persistent defects, significantly more were free from angina. No difference was observed between group 1 and 2 in percentage stenosis of the vessel or in reduction of the diameter. Significant reduction in the extent of reversible perfusion defects after PTCA was observed in both groups and also in the extent of persistent defects in group 2. In about 1/3 of the patients, the changes in percentage stenosis after PTCA and in the perfusion as judged by the scintigraphies differed. Therefore, as the two methods supplement each other, the main conclusions are: 1) Evaluation of the revascularization procedure is more reliable if a scintigraphy is obtained both before and after PTCA than if only coronary arteriography is performed. 2) Scintigraphy alone suffices for the three-month follow-up examination, partly because it gives better information about the myocardial perfusion than does the arteriography, partly because scintigraphy is a noninvasive procedure.

[Confidence intervals instead of p-values]. / Sikkerhedsintervaller i stedet for p-vaerdier.

International scientific journals expect authors of articles to an increasing extent to calculate confidence intervals for their statistical findings. Confidence intervals are more informative than p-values in hypothesis testing as the confidence interval expresses how great the value of an investigated effect may be anticipated to be in the population. Examples of calculation of confidence intervals are presented on the basis of data frequently occurring in medical investigations.