Cardiac Dysrhythmias in Patients with Acute Myocardial Infarction

Abstract A series of 676 patients with acute myocardial infarction were evaluated with regard to initial serum potassium level, prior diuretic therapy and occurrence of cardiac dysrhythmias during their first 24 hours in a coronary care unit. Serious dysrhythmias (ventricular tachycardia, ventricular fibrillation, and asystole) were significantly more frequent in hypokalemic patients. In this regard no differences were observed between patients on or off prior diuretic therapy     

Diabetes Mellitus in Friedreich's Ataxia

In a clinical study of Friedreich's ataxia diabetes mellitus was found in nine of 50 typical cases. The mean age of the diabetes onset was 21.9 years and the clinical type was a severe ketosis-prone diabetes. In 18 non-diabetics an intravenous glucose tolerance test was performed. One of these cases was disclosed to be a prediabetes. The mean rate of glucose disappearance was normal. Serum lipid analysis showed a slight elevation in non-diabetics and a higher in diabetics. The frequency of diabetes mellitus, including the prediabetic case, was 20%. Owing to the low age of the cases and as the glucose tolerance test was performed only in about half of the non-diabetics, this figure was estimated to be lower than the total frequency in Friedreich's ataxia. A brief survey of the literature is given, and the aetiology of diabetes mellitus in Friedreich's ataxia is discussed. The marked frequency of a known heredity to diabetes in the diabetic cases lends support to the hypthesis of a genetic aetiology. The possibility of an interplay between the defective genes of the two diseases is assumed. The pronouncedly vegetative syndrome occurring in Friedreich's ataxia suggests the possibility of a central nervous factor, though this can hardly be a primary cause of the diabetes.     

Electrophysiological effects of prenalterol on the cardiac conduction system

The electrophysiological effects of prenalterol, a new beta-receptoragonist, in a dose of 100 µg/kg body weight given intravenouslyfor 5 min, were studied in 13 patients with signs of sinus nodedysfunction and/or conduction defects within or distal to theatrioventricular (AV) node. In nine patients with signs of sinus node dysfunction a significantreduction was found in corrected sinus node recovery time, onan average by 1955±640ms (–61%, P<0.05) andin atrial refractoriness, by 61 ±21 ms (–20%, P<0.05).Similar but insignificant changes were also seen in the fourpatients with normal sinus node function. In eight patientswith AV nodal dysfunction, a significant increase was foundin the Wenckebach point, by 51±10b.p.m (+52%. P<0.01)and a decrease in the AH interval, by 23±9ms(–14%,P<0.05). AV nodal refractoriness tended to decrease by 115±58ms(–24%, NS). Similar changes were found in the five patientswith normal AV conduction. Heart rate increased in all 13 patients,on an average by 28±5 b.p.m. (+44%, P<0.001) and systolicblood pressure by 18±8 mmHg (+13% P0.01). In conclusion, prenalterol increased sinus node automaticityand atrial and AV nodal conductivity, but did not improve infranodalconduction. Thus, the drug might be useful in the treatmentof patients with sinus node dysfunction as well as in patientswith spontaneous or induced atrioventricular conduction abnormalities.     

Histamine nasal provocation test

This study is a methodological approach to histamine nasal provocation. The test uses active anterior rhinomanometry and a histamine titration method, challenging both nasal cavities with a metered dose pump. It has been confirmed that the histamine nasal provocation test can differentiate between controls and non-allergic rhinitis patients. This study shows, moreover, that the method is more sensitive in assessing response to histamine provocation when a 25% increase of post-saline nasal airway resistance (PD25) is considered than a PD50 or PD100 criterion. The histamine response, was found to be independent of the baseline nasal airway resistance value. Pronounced unilateral responsiveness was frequently noticed. Both nasal cavities should be challenged and the most reactive side considered.     

The Adherence of Polymorphonuclear Leucocytes to an Albumin-coated Glass Surface

ABSTRACT. Dahlgren C, Norberg B, Eriksson S (Department of Medical Microbiology, University Hospital, Linköping, and Departments of Internal Medicine and Geriatric Medicine, University Hospital, Umeå, Sweden). The adherence of polymorphonuclear leucocytes to an albumin-coated glass surface. Acta Med Scand 1987; 221:109–13. The Catharantus derivatives are microtubule antagonists employed in immunosuppression and chemotherapy of neoplasms. The role of cytoplasmic microtubules in polymorphonuclear leucocyte (PMN) adherence was studied by means of therapeutic concentrations of the Catharantus derivatives vincristine, vinblastine and vindesine. PMN adherence was measured as retention on an albumin-coated glass surface. PMN adherence was reduced by 4–54% by the Catharantus derivatives, as compared with control values. The suppression of adherence was statistically significant. Since the Catharantus derivatives are microtubule antagonists, it is reasonable to assume that PMN adherence is a partially microtubule-dependent process. It is suggested that reduction of PMN adherence could account for at least Dart of the immunosuppressive properties of the Catharantus derivatives.