European journal of cardiology最新文献

A case of intermittent and at times alternating, nonrate-dependent left bundle branch block, with alternation of normal and reduced indexes of contractility (dP/dt, dP/dt/P) in a borderline normal heart is reported. The reduction of left ventricular contractility in the presence of left bundle branch block, as compared to what is found by other authors, is supposedly related to a different location of the block in the left branch (peripheral vs high).

Na+,K+-ATPase activity was assessed indirectly in three groups of subjects of differing age, and in a group of patients with renal failure, by measuring the 86-rubidium uptake in the patients' own erythrocytes. The inhibiting action of digoxin on this activity was also measured in vitro. Erythrocyte 86Rb uptake was found to be lower in the elderly as was the calculated volume of distribution of digoxin. Sensitivity to the inhibiting action of digoxin increased with age. In the renal failure group 86Rb uptake was diminished and the sensitivity to digoxin was variable. This suggested that Na+,K+-ATPase activity could be one determinant of the volume of distribution of digoxin and that quantitative and qualitative changes of this enzyme could explain features of the pharmacokinetics of digoxin in renal failure and in old age.

Measurements of plasma pancreatic polypeptide and gastrin are reported for the first time in patients with acute myocardial infarction and compared with clinical signs of vagal or sympathetic overactivity. Pancreatic polypeptide concentrations were assessed as an index of vagal activity, but elevated values of pancreatic polypeptide found in 7 of the 13 patients on admission did not correlate with clinical evidence of vagal overactivity. The mean pancreatic polypeptide concentrations were not higher in patients with clinical vagal overactivity than in patients with clinical sympathetic overactivity during the 12 h after the onset of symptoms of acute myocardial infarction. Mean gastrin levels were significantly higher on admission and at 4, 5, 6 and 8 h after the onset of infarction in the patients with clinical features of sympathetic overactivity than in the patients with clinical vagal overactivity. Thus plasma gastrin warrants further assessment as an index of sympathetic overactivity in acute myocardial infarction.

This report describes a young boy with previous myocardial infarction and hypertension. Demonstration of coronary arterial ostial stenosis and a variant of subclavian steal was documented by selective arteriography. Surgical resolution of the most important stenosis is descending aorta, permitted effective control of hypertension. It is considered that one could reach this arteritis through different etiologies, tuberculosis having a preponderant place, and that it is important in all cases to carry out coronary arteriography.

Development of an experimental preparation aided to investigate arrhythmogenic and antiarrhythmogenic factors influencing incidence of spontaneous and yet predictable ventricular arrhythmias is described. Using the isolated perfused guinea-pig heart and a system for quantitating rhythm disturbances based on computer-aided statistical analysis of beat-to-beat intervals, a number of factors influencing the incidence of rhythm disturbances were investigated. Manipulation of perfusate composition revealed that, after 'moderate' ischaemia, reperfusion arrhythmias were increased in the presence of noradrenaline and non-glucose fuels. Free fatty acids, unless in the presence of catecholamines, were not particularly arrhythmogenic. In contrast, the presence of pyruvate or lactate, endproduct inhibitors of glycolysis, significantly increased incidence of reflow rhythm disturbances. The dose-dependent arrhythmogenic effects of pyruvate and anti-arrhythmogenic effects of glucose support the thesis that inadequate glycolytic flux could be important in the development of arrhythmias.

Lorcainide hydrochloride given at the doses of 150 mg i.v. proved to be well tolerated at the acute stage of a myocardial infarction; the subjective signs were benign and never prevented us from completing the injection. The haemodynamic changes reflect some depressive effects on the myocardial function. Most of the observed changes are transient, and when significant from the statistical point of view, they remain very mild: the cardiac output decreased from 3.4 to 3.2 l/min per m2, the stroke index from 46 to 41 ml/m2, the pulmonary wedge pressure increases from 6.6 to 8.4 mm Hg (mean values). Lorcainide hydrochloride may thus be used as an antiarrhythmic drug in acute myocardial infarction.

Instantaneous measurements of ejection phase indices throughout the whole systole have been performed in 10 normal subjects (normal group), and in 8 coronary artery disease (CAD) patients (CAD group). All the patients of the CAD group were selected from 230 CAD patients because of their normal values in standard ejection phase indices (i.e. ejection fraction, EF; mean velocity of circumferential fiber shortening, VcfM; mean normalized systolic ejection rate, MNSER). An 'instantaneous' evaluation of the ventricular function, by means of a frame-by-frame analysis throughout the ejection period, allowed us to detect abnormalities of ventricular ejection in the early phase of systole in these CAD patients. In comparison with the control group, the CAD group presented similar peak values of dV/dt, dV/dt/EDV and Vcf, and a significantly longer time to peak values of these indices; EF curve analysis showed similar values at the end of systole in the two groups, but the mean curve of the CAD group was significantly lower in the first third of ejection when compared with that of control group. A segmental wall motion analysis in the early phase of systole showed a diffuse delayed ventricular wall motion (tardokinesis) related to abnormalities demonstrated by frame-by-frame analysis of ejection phase indices. Our results confirm that the CAD patients may have abnormalities of ventricular performance in the early phase of systole even when standard ejection phase indices are still within the normal range. In addition, the chronological appearance of these abnormalities during the whole systole has been clearly assessed; finally, these data confirm the importance of acceleration in blood ejection from the left ventricle as an index of ventricular function.

Report of a case of obstructive dysfunction of a tricuspid Starr-Edwards (6120) ball prosthesis, diagnosed on phonocardiographic (PCG) diastolic anomalies with abnormal diastolic pattern of the jugular pulse, abnormal jugular flow velocity curve, and confirmed by cinefluoroscopy. The thrombotic origin of the obstruction was assessed on the regression of PCG and cinefluoroscopic anomalies under fibrinolytic therapy.