[Why there is atrial fibrillation after cardiac operations?]. / Preco vzniká fibrilácia predsiení po kardiochirurgických operáciách?

Atrial fibrillation (AF) is the most frequent arrhythmias after cardiac operations. Its incidence ranges from 10-65%. Often there is a patient discomfort, prolongs hospitalization, increases costs of operation and may be permanent or recurrent course. The cause of postoperative AF is multifactorial. The prevention of non-pharmacological and pharmacological interventions. The conventional treatment strategies include monitoring ventricular rate, restoration of sinus rhythm and prevention of thromboembolic events. The development of effective therapies designed to decrease the high incidence of postoperative AF may be important in the future.

The effect of myocardial revascularization on malignant ventricular arrhythmias in coronary artery disease.

BACKGROUND: Malignant ventricular arrhythmia in coronary artery disease (CAD) is a severe life-threatening disease and a risk factor for sudden cardiac death. Myocardial revascularization influences the arrhythmogenic substrate of the malignant ventricular arrhythmia in the secondary prevention of sudden cardiac death. Its effectivity remains controversial. OBJECTIVES: The aim of this study is to assess the inducibility of sustained ventricular tachycardia (VT) or ventricular fibrillation (VF) in patients after myocardial revascularization and to compare the effectivity of complete and incomplete revascularization. PATIENTS: Fifty patients with documented sustained VT or VF and CAD were examined in our department. RESULTS: Conservatively treated patients were significantly older than revascularized patients (68 +/- 8 versus 62 +/- 9 years, p<0.05). We registered a trend towards a lower inducibility of malignant ventricular arrhythmias in the revascularized group and completely revascularized subgroup, but without statistical significance. Incompletely revascularized patients comprised only of men (100% versus 66.6%, p<0.05). Fewer ICDs were implanted in the completely revascularized group (55.6% versus 92.3%, p<0.05). CONCLUSION: Myocardial revascularization has little effect on the inducibility of malignant ventricular arrhythmias after myocardial revascularization. Complete revascularization significantly decreases the need of ICD implantation when compared to incomplete one (Tab. 3, Fig. 4, Ref. 24). Full Text (Free, PDF) www.bmj.sk.

[Non-fluoroscopic mapping techniques in contemporary catheter ablation therapy of dysrhythmias]. / Nefluoroskopické mapovacie techniky v súcasnei katétrovei ablacnei liecbe dysrytmií.

Rapid development and clinical introduction of 3D techniques of intracardial mapping significantly extended the possibilities of catheter ablation therapy of dysrhythmias. Contemporary imaging techniques allow precise determination of the source and the way of propagation of dysrhythmia in myocardium, which is an evitable condition of a successful ablation therapy. Although the fluoroscopic image during electrophysiologic examination allows continuous check of the position of catheters in the heart, due to its low resolution it remains just rough estimation of their real position. The objective of the authors of this lucid work was to give a brief characteristic of the basic principles of the activity of 3D mapping systems used nowadays and to approximate their significance and advantages for ablation therapy of individual dysrhythmias in clinical practice.

[Plasminogen activator inhibitor-1 (PAI-1), ischemic heart disease and diabetes mellitus]. / Inhibítor aktivátora plazminogénu (PAI-1), ischemická choroba srdca a diabetes mellitus.

The classic risk factors can only in part explain the increased incidence and extent of coronary artery disease. Plasminogen activator inhibitor type-1 (PAI-1), the main human regulator of endogenous fibrinolysis, is considered to be an important cardiovascular risk factor. The article discuss the current knowledge of the PAI-1 importance and role in the in the pathogenesis of atherosclerosis and mechanisms of its synthesis predominantly in patients with coronary artery disease associated with diabetes mellitus type 2. It explains contributions of PAI-1 to the pathophysiologic links between diabetes mellitus and cardiovascular diseases and shows current therapeutic interventions normalising PAI-1 activity, their beneficial effect on prognosis and course of coronary artery disease.

[Effect of passive leg lifting on sodium excretion in patients with liver cirrhosis]. / Vplyv pasivneho zdvihnutia dolnych koncatin na exkreciu sodika u chorych s cirhozou pecene.

18 healthy subjects and 15 patients with liver cirrhosis were examined using a 2-hour method of passive leg rising (PLR). Renal and hormonal responses to PLR were investigated. There was a significant increase in diuresis (p < 0.01) and sodium excretion (p < 0.01) simultaneously with a decrease in plasma renin activity (p < 0.01) and plasma aldosterone (p < 0.01) in the group of healthy subjects. Similarly, in the group of patients with liver cirrhosis a significant increase in diuresis (p < 0.01), natriuresis (p < 0.05) together with a decrease in plasma renin activity (p < 0.05) and aldosterone (p < 0.01) were detected. 3 of 15 patients were nonrespondents. We conclude that PLR leads to central volume expansion which causes suppression of sodium retaining factors, and the increase in diuresis and natriuresis not only in healthy objects but also in cirrhotics. This simple method may be used as the first therapeutic regimen in patients with cirrhosis and edemas. (Tab. 2, Fig. 3, Ref. 13.)

[High resolution electrocardiography of P-wave signals in clinical cardiology]. / Význam vysokorozlisovacej elektrokardiografie vlny P v klinickej kardiológii.

Signal-averaged electrocardiography of the QRS complex detects presence of late potentials which represent significant arrhythmogenic marker responsible for increased risk of life-threatening ventricular arrhythmias especially in post myocardial infarction patients. The P wave signal-averaged electrocardiography has been designed to predict development of atrial fibrillation in different populations of patients. Many P wave signal-averaging methodological procedures have been developed. However their common disadvantages remain lack of standardization, relatively low specificity and sensitivity, low positive predictive value as well as limited number of larger prospective clinical trials. Recent software and technological improvements of the P wave high resolution techniques as well as some new reports about the influence of antiarrhythmic drugs on the parameters of the P wave signal-averaged electrocardiography are creating new possibilities not only for the diagnosis of paroxysmal atrial fibrillation but also for the prediction of antiarrhythmic drug efficiency.

A study of the renal sodium excretion during the normal menstrual cycle using method of passive leg rising.

12 healthy women (age 18-38 years) were examined using the 2-hour's method of passive leg rising (PLR) in follicular (FP) and luteal (LP) phases of normal ovulatory cycle. Renal and hormonal response to PLR was investigated. There was a significant increase of diuresis (from 53 +/- 9 ml/h to 298 +/- 27 ml/h in FP, from 69 +/- 12 to 324 +/- 28 ml/h in LP) and natriuresis (from 4.5 +/- 0.9 to 9.8 +/- 1 mmol/h in FP, from 5.7 +/- 0.3 to 12.1 +/- 1.1 mmol/h in LP), simultaneously with a decrease of plasma renin activity (PRA) and plasma aldosterone (PA) in both FP and LP. Baseline PRA was mildly and PA was significantly higher in LP compared to FP. Urinary osmolarity, heart rate and systolic blood pressure dropped significantly. Renal and hormonal response to PLR were identical in the two phases of the menstrual cycle. Authors conclude that 1/PLR causes significant diuresis and natriuresis due to central volume expansion and may be used as a simple stimulating test of renal sodium excretion, 2/renal sodium retention does not occur in the LP of normal ovulatory cycle.