European journal of cardiology最新文献

3 patients with atrial fibrillation, of varying origin, have been successfully converted to sinus rhythm by D.C. shock while on the antiarrhythmic drug amiodarone. D.C. shock did not cause rhythm disturbance. D.C. conversion may not be contraindicated in patients taking amiodarone.

The St. Jude medical (SJM) heart valve prosthesis presents a new bi-leaflet design which in preclinical evaluation exhibited favourable haemodynamic characteristics. Therefore clinical trials started in February 1978. The entire valve is made of pyrolytic carbon which has a poor X-ray visibility and therefore an alternative for the noninvasive routine control of valvular function and postoperative follow-up had to be found. Experimental studies in a left heart simulator provided adequate echovisualisation of both leaflets, however, depending on the direction of their motion in relation to the echobeam. Identification of both leaflets and an analysis of their motion was possible with a transducer at right angles to the leaflet axis. The experimental data were confirmed by clinical observations after implantation of the SJM prosthesis in patients. Based on the information obtained, we are providing recommendations for the implantation of the SJM prosthesis in order to achieve optimal echocardiographic visualisation of the valve and its moving parts in the postoperative follow-up.

Previous studies have shown a significant relationship between the clinical effect of digoxin and a tissue response, namely the inhibition of 86Rb uptake by the patients' erythrocytes. In the present study, this relationship is confirmed in patients, in heart failure with sinus rhythm. The slowing of the heart rate but not the QS2 index changes correlates significantly with the 86Rb uptake inhibition.

A case with a ball thrombus in the left atrium with a normal mitral orifice is presented. This is an extremely rare combination. The patient, aged 76, suffered from attacks of cyanosis, dyspnoea and shock because of lodging of the thrombus in the mitral orifice. In addition she had abdominal pain. The autopsy showed the thrombus in a dilated left atrium, and there were recent infarctions in the liver and a thrombus in the left renal artery. The clinical diagnosis is difficult because of the rarity of this phenomenon, but one should think of emboli from the left atrium, when an atrial fibrillation is diagnosed. One should also consider the possibility of a myxoma with these symptoms.

Electrophysiologic and histopathologic correlation has been carried out in a patient with scleroderma heart disease, affected by syncopal seizures, who died of recorded ventricular fibrillation. The electrophysiological investigation disclosed dysfunction of sinoatrial conduction, revealed by sinoatrial blocks and by an abnormal return cycle pattern after premature atrial beats. Atrial effective and functional refractory periods were increased and an unusual 'pseudo-Wenckebach' phenomenon between artificial stimulus and atrium was observed during atrial pacing. Intra-AV nodal conduction time was at normal upper limits and Wenckebach-type AV block was obtained on pacing the atrium at 100 beats/min. HV conduction was moderately prolonged in the presence of left anterior hemiblock. The histopathologic substrates of these electrophysiologic disturbances were fibrosis of the sinus node, disrupted internodal pathways and atrio-AV nodal connections, and left bundle branch atrophy. As far as fatal tachyarrhythmia is concerned, myofibrillar degeneration may have contributed to its pathogenesis. It is suggested that both lesions of the ordinary myocardium and specialized conduction system account for the electrical instability of sclerodermic patients.

We studied 9 men with antero-apical left ventricular aneurysms. All suffered from incapacitating angina pectoris without heart failure. Aneurysmectomy was done in 4 patients as the sole procedure while it was combined with revascularisation of the residual myocardium in the other 5. Haemodynamic measurements were made at rest and during submaximal supine-leg exercise before and approximately 6 mth after operation in each patient. Compared to the preoperative levels, we observed a significant increase in respiratory rate at rest (P less than 0.001) and during exercise (P less than 0.01), in ventilation during exercise (P less than 0.05), in mean pulmonary arterial pressure at rest (P less than 0.001) and during exercise (P less than 0.01) and in mean pulmonary wedge pressure during exercise (P less than 0.01). These changes were accompanied by a significant reduction in cardiac output during exercise (P less than 0.01) and in stroke volume at rest (P less than 0.05) and during exercise (P less than 0.01). Heart rate and blood pressure remained essentially unchanged. . The curve representing the relationship between the left ventricular stroke work and the filling pressure shifted downwards and to the right after operation compared to that before operation. Patients who show only minimal haemodynamic disturbances associated with an aneurysm, maintain an effective forward stroke volume by an augmented fibre-shortening of the residual myocardium as well as an increase in the diastolic volume of the heart. Results of our study demonstrated that the compensatory ventricular dilatation may be critical in this group of patients. Despite an increase in average ejection fraction after operation, the removal of the aneurysm led to considerable haemodynamic deterioration in all the patients studied.

The authors compare the effects of beta-blockers without intrinsic sympathetic activity (ISA) (propranolol, 160 mg/day), moderate ISA (acebutolol, 800 mg/day) and high ISA (pindolol, 20 mg/day). The sinus rate decreases more with propranolol than with acebutolol, during the day (P less than 0.01) and during the night (P less than 0.001), whereas pindolol does not change the daylight rate and increases the nighttime rate (P less than 0.001). The ventricular rate during atrial fibrillation (AV nodal transmission) is modified as is sinus rate. There is no significant difference between propranolol and acebutolol, and a highly significant difference between pindolol and propranolol (P less than 0.001) or acebutolol (P less than 0.01). Moreover, the eurythmic effect of beta-blockers, making RR intervals more regular, is maximal with propranolol and minimal with pindolol, as judged on RR interval histograms. The ISA of the beta-blockers is of major importance for the clinical use of these drugs, and in the case of SA or AV node dysfunction ISA can be useful, but it can obscure the beneficial effects of beta-blocking therapy.

The pulsed Doppler echocardiography (PDE) was used to evaluate the character of mitral valve flow in a large atrial tumor. The tumor obstructed the mitral orifice during diastole. PDE findings, however, showed normal triphasic diastolic flow within the actual mitral orifice and no changes typical for mitral stenosis. The same turbulence pattern as in mitral stenosis was detected in the left ventricle. In addition, PDE revealed the presence of mild mitral regurgitation in agreement with angiography.