Arrhythmias in congenital heart defects.

AIM OF THE STUDY: Evaluation of the incidence and severity of late arrhythmias in patients with predisposing congenital heart defects--either due to the anatomy of the defect itself or as a result of a particular type of surgical intervention. PATIENTS AND METHODS: In a retrospective long-term study authors analyzed 158 patients (divided into 5 groups) with congenital heart defects after surgical correction. Evaluated were: the incidence of rhythm disturbances, the type of arrhythmia and the need for medication or intervention. RESULTS: The most rhythm disturbances occurred in patients after physiological correction of D-transposition of the great arteries (68.5%) and these patients also mostly needed medication or pacemaker implantation; followed were by patients with hypoplastic left heart syndrome after Fontan procedure (40%), then were patients after long-term correction of tetralogy of Fallot (31.1%), atrial septal defect sinus venosus type with partial anomalous pulmonary venous return after Warden correction (25.7%) and congenitally corrected L-transposition of the great arteries (25 %). Most of these arrhythmias were asymptomatic and there was no need to treat them. There was an increased incidence of arrhythmias with time (p < 0.05). DISCUSSION: During childhood in patients after surgical correction late arrhythmias mostly do not represent a severe problem, but with time, when reaching adulthood, this may be an issue. It is therefore very important to understand the anatomy, physiology and the arrhythmogenic substrate of every high risk congenital heart defect (Tab. 2, Fig. 6, Ref. 10).

Prospective study of antibacterial susceptibility, risk factors and outcome of 157 episodes of Acinetobacter baumannii bacteremia in 1999 in Slovakia.

This study prospectively investigated all 157 cases of Acinetobacter baumannii bacteremia occurring in major university hospitals or tertiary care institutions in Slovakia during 1999 in order to determine the antimicrobial susceptibility, risk factors and outcome. Resistance to meropenem was 7.4, gentamicin 35.6, amikacin 26.5, cefepime 20.4 and ciprofloxacin 32.7%, but was only 17.3% to cefoperazone/sulbactam or ampicillin/sulbactam. Antimicrobial susceptibility of A. baumanii was lowest among isolates from cancer patients (ceftazidime 58%, piperacillin/tazobactam 52% and azthreonam 48%; p < or = 0.01-0.001). In univariate analysis, several risk factors, such as wound infection (p < or = 0.01) and ventilatory support (p < or = 0.0001), were significantly related to A. baumannii bacteremia in surgical patients. Neutropenia (p < or = 0.0001), antineoplastic chemotherapy (p < or = 0.0001) and prior antibiotic therapy (p < or = 0.0006) were significant risk factors for A. baumannii bacteremia in cancer patients. In addition, ventilatory support and surgery (p < or = 0.0001) and prior antibiotic therapy (p < or = 0.01) were significantly related to A. baumannii bacteremia in children. Colonization at other body sites (p < or = 0.05), diabetes mellitus (p < or = 0.04) and decubital ulcers/burns (p < or = 0.002) as underlying disease were significantly related to death due to A. baumannii bacteremia. In a multiple logistic regression model, decubital ulcers/burns as underlying disease (p < or = 0.0006; relative risk 5.08) and nosocomial pneumonia (p < or = 0.045; relative risk 5.08) were independent predictors of mortality. Mortality was similar between cancer and surgical patients but significantly lower in children vs. adults (p < or = 0.009).

Native valve staphylococcal endocarditis: etiology, risk factors and outcome in 53 cases.

Fifty-three cases of staphylococcal endocarditis from a national endocarditis survey were analyzed for risk factors and outcome. Thirty of 53 patients had predisposing heart disease (39.6% rheumatic fever) but only 3 were on dialysis, only 2 had central venous catheter, only 2 intravenous drug abuse but 7 had prior cardiosurgery. Mortality was 39.6%. In analyzing risk factors for death, attributable mortality was significantly associated with skin infections (P < 0.05), embolization (P < 0.02), inappropriate therapy (P < 0.005) either because of too short therapy (P < 0.003) or wrong antibiotic combination (P < 0.01). Surgical therapy was associated with better outcome (4.8% deaths vs. 31.2% survivors, P < 0.04).

Triggered activity as the proposed mechanism of left atrial tachycardia induced by premature ventricular beats.

In a 57-year-old woman with complex ventricular ectopy, a paroxysmal supraventricular tachycardia initiated by premature ventricular beats is presented. She underwent an electrophysiologic study. The tachycardia origin was localised to the left atrium. At the presence of retrograde dual atrioventricular nodal pathway, the atrial tachycardia was induced by programmed ventricular stimulation. Triggered activity was shown to be the likely mechanism of both atrial and ventricular arrhythmias.

Parasympathetic overactivity and its evaluation in patients with sinus nodal dysfunction.

In 17 controls, and 17 patients with sinus nodal dysfunction, an electrophysiologic study was made of sinus nodal function and atrioventricular nodal conduction in the basal state. The study was then repeated in all patients after atropine. The heart rate, mean sinus cycle length, variations of sinus cycle length, sinus node recovery times, sinuatrial conduction time, AH interval, and atrioventricular nodal Wenckebach threshold were significantly different in patients from those of controls. All these parameters changed significantly in patients after atropine, and were comparable to those of controls except for the atrioventricular nodal Wenckebach threshold. Atropine failed to increase the heart rate beyond 90 beats per minute in 10 of 17 patients (sensitivity of 59%) or by at least 30% above the resting heart rate only in 4 of them (sensitivity of 24%). The variations of sinus cycle length, and their standardized value, could detect sinus nodal dysfunction with sensitivities of 59 and 47%, respectively. From our results, we conclude that there is parasympathetic overactivity in patients with sinus nodal dysfunction. Because of their very low sensitivities, the atropine test and variations of sinus cycle length were not useful in identifying sinus nodal dysfunction noninvasively. The normal response of the heart rate to atropine does not exclude sinus nodal dysfunction, but atropine may help to differentiate abnormalities intrinsic and extrinsic to the sinus node during the electrophysiologic study.

[Ventricular tachycardia in patients with arrhythmogenic right ventricular dysplasia. Electrophysiologic characteristics and testing of the effectiveness of anti-arrhythmia therapy]. / Komorová tachykardia u chorých s arytmogénnou dyspláziou pravej komory. Elektrofyziologická charakteristika a testovanie úcinnosti antiarytmickej terapie.

The authors present a clinical and electrophysiological characteristic in two cases of symptomatic sustained ventricular tachycardia (VT) with a QRS morphology of left bundle branch block, refractory to common antiarrhythmic treatment. It was confirmed that the mechanism of this arrhythmia associated with a high risk of sudden death is the reentry phenomenon and the authors analyzed its relationship to arrhythmogenic dysplasia of the right ventricle. In a way uncommon in our literature the authors demonstrate the importance of comprehensive electrophysiological examination in these serious cases and its usefulness in confirming the origin of VT in the right ventricle, its importance for mapping the accurate localization of tachycardia and the investigation of effectiveness of drugs and the evaluation of aptness of non-pharmacological treatment.

Retrograde dual atrioventricular nodal pathway in patients with atrioventricular reciprocating tachycardia using concealed accessory pathways.

We present electrophysiological studies in two patients with atrioventricular reciprocating tachycardias. The first patient had anterograde dual atrioventricular nodal pathways with a right-sided concealed accessory pathway. The retrograde atrioventricular nodal pathway showed evidence suggestive of slow pathway properties. After block was induced with ajmaline in the accessory pathway, a typical pattern of discontinuous retrograde atrioventricular nodal conduction curves was recognized. We then observed three types of induced atrioventricular reentry. The other patient had continuous anterograde atrioventricular nodal conduction, a fast-conducting retrograde atrioventricular nodal pathway and a left-sided concealed accessory pathway. After refractoriness had been induced in the accessory pathway with ajmaline, a typical pattern of retrograde dual atrioventricular nodal pathways was recognized, and it proved impossible to induce atrioventricular nodal echoes. Induction of block or impairment of conduction with ajmaline in the concealed accessory pathway proved helpful in the disclosure of retrograde dual atrioventricular nodal pathways by means of the ventricular extrastimulus method.

[A rational diagnostic program for hypertension in children]. / Racionálny diagnostický program hypertenzie u detí.

Early screening of subjects liable to develop cardiovascular diseases is one of the main tasks of preventive cardiology of child age. The authors present a rational programme for the screening and diagnostic of hypertension in children, its aim being to differentiate primary and the most frequent secondary forms of hypertension; this will create prerequisites for its adequate treatment (non-pharmacological and pharmacological) as well as for dispensarization. Review.

Comparison of indirect and direct methods for determination of sinoatrial conduction time.

We have performed an electrophysiologic study (EPS) in 18 subjects (mean age 21 +/- 17 years) with normal sinus node function (group A) and in 15 patients (mean age 43 +/- 26 years) with sinus node dysfunction (group B). Three extrastimulus methods (both Strauss and Kirkorian methods and our modification of the extrastimulus method) were carried out in 31 patients of both groups and sinoatrial conduction times (SACTSTR, SACTKIR,SACTMOD) could be estimated in 27 of them. SACT by the Narula method (SACTNAR) was assessed in 25 patients of both groups. Sinus node electrograms (SNEs) were attempted in 22 patients and were obtained in 17 of them. Among the indirect methods, by comparison with SACTSTR in group A the best correlation was for SACTMOD (r = 0.81) and the weakest for SACTKIR (r = 0.67); there was no significant difference between SACTs estimated by Strauss and other methods. In group B the weakest correlation was also for SACTKIR (r = 0.68), whereas the correlations for both SACTMOD and SACTNAR were similar (r = 0.72 and r = 0.74, respectively); in this group SACT was significantly underestimated only by the Kirkorian method (P less than 0.01; sensitivity of 45%). By our method sensitivity was 82%, similar to both the Strauss and Narula methods (92 and 92%, respectively). By comparison of indirect methods with the direct measurement of SACT we have found similar good correlations for the Strauss, our own, and the Narula methods in group A (r = 0.81, r = 0.75, r = 0.79, respectively) and in group B (r = 0.81, r = 0.86, and r = 0.72, respectively); here too the weakest correlation was, in both groups, for the Kirkorian method (r = 0.67, and r = 0.68, respectively). The SACT in group B was the more significantly underestimated (P less than 0.001). Significant underestimation of SACT occurred also by our method and the Strauss method (P less than 0.01, and P less than 0.001, respectively), whereas the Narula method did not significantly underestimate the directly measured SACT. From the SNEs after atrial pacing we have shown the limitation of the Kirkorian method and observed the conspicuous beat-to-beat variability of SACTdirect' as the possible explanation of chaotic pattern of return cycles by the extrastimulus methods in some patients of group B.(ABSTRACT TRUNCATED AT 400 WORDS)

Treatment of renal hypertension in children by captopril.

Nine children aged 2 months to 13 (mean 6.6) years with renal hypertension were treated with captopril. The treatment lasted for 1.5 to 14 months. Maintenance doses ranged between 1 and 5 mg/kg/day. Good effect was achieved with captopril in children with normal renal function and in mild renal insufficiency. In patients with end-stage renal disease when dialysis failed to maintain normal body water captopril was ineffective.

Pediatrical case histories analyzed by means of a computer.

The authors present their first version of the formation of anamnestic case histories (family, personal, epidemiological, and social) by means of a conversation between the physician and the computer. During the recording a set of the means of expression is used, this allows for an exhaustive compilation and recording of various types of case histories. The means of expression called variables make up the questionnaire sentence. The case histories- conversations about them, are presented by the algorithm of the questionnaire in logical sequences which permit suprabound jumps off to other linkages. The created complexes-sentences are verified as a whole and then recorded. Portions of different types of case histories are demonstrated in this paper together with their possible side jumps. The possibilities of computer analysis lie in repeated recording, corrections, in the formation of statistical analyses of various data and, in the future, also in the formation of differential diagnostic considerations with the assistance of computers.