[Atrial fibrillation in Wolff-Parkinson-White syndrome]. / Fibrilhação auricular na síndroma de Wolff-Parkinson-White.

The authors describe the main etiopathogenic factors and clinical importance of atrial fibrillation and analyse the results of catheter ablation of atrioventricular accessory pathways in Wolff-Parkinson-White syndrome. Atrial vulnerability is the principal mechanism and radiofrequency catheter ablation of atrioventricular accessory pathways seems to be useless to prevent atrial fibrillation.

[Guided anti-arrhythmia therapy by programmed ventricular stimulation. A case of arrhythmogenic dysplasia of the right ventricle]. / Terapêutica antiarrítmica guiada por estimulação ventricular programada. Um caso de displasia arritmogénica do ventrículo direito.

Right ventricle dysplasia (RVD) is a rare clinical entity, described in young people, and a known cause of ventricular arrhythmias and sudden death. A genetic transmission has been suggested from the study of familial cases. The disease is characterized by a dilated right ventricle, cardiac infiltration with fatty tissue and focal fibrosis. Lymphoplasmocyte infiltrates are documented. The diagnosis is based on electrocardiography, echocardiography, magnetic resonance imaging and right ventricular endomyocardial biopsy. The authors report a case of a young woman with symptomatic ventricular tachycardia (VT) in whom the diagnosis of RVD was established. Programmed ventricular stimulation was used to reproduce the clinical VT and to test the efficacy of the anti-arrhythmic drug therapy. The diagnosis criteria and therapeutic options are discussed.

[Prevalence of human herpesvirus 7 in Mexican blood donors]. / Prevalencia del virus humano herpes 7 en donadores de sangre Mexicanos.

The human herpes virus 7 (HHV-7) has been recently isolated from CD4 cells of healthy persons. The present study describes the antibody prevalence of this virus in a healthy Mexican population. Two hundred blood samples from candidates for blood donation at the Hospital General de Mexico were studied with the indirect immunofluorescence test (IFA) in HHV-7 infected SupT1 cells. The testing was done in the University of Cologne, Germany; 167 were males and 33 female; the donors came from 12 of the 31 states in the Mexican republican, predominantly from Mexico City (60.5%) and the State of Mexico (28%). Their mean age was 29.2 years. All but three samples were positive to the HHV-7 (98.5% positivity). Nearly 85% had high titers (> or = 1:80). Other serology testing in the samples revealed 1% positive tests to hepatitis B, 2% to syphilis, and 0.5% to brucella. Hepatitis C and the HIV test were negative in all. The high prevalence of HHV-7 in our donor population should be further studied in order to determine titers indicative of an active infection and of their association with illnesses.

[The QTc interval and its dispersion in hypertrophic myocardiopathy--its relation to complex ventricular arrhythmias and the effect of anti-arrhythmia agents]. / Intervalo QTc e sua dispersão na miocardiopatia hipertrófica--relação com arritmias ventriculares complexas e efeito dos fármacos anti-arrítmicos.

UNLABELLED: The aim of the present study was to evaluate, in patients with hypertrophic cardiomyopathy (HCM): 1. The relation of rate corrected QT interval (QTc) and of QTc interlead variability (QTc dispersion) to complex ventricular arrhythmias (CVA); 2. The effects of amiodarone (Am), beta-blockers (beta B) and calcium antagonists (CA) on QTc and on QTc dispersion. Surface 12 leads ECG was analysed in 55 patients with HCM (39 +/- 12 years, 32 males). All patients were in sinus rhythm, without bundle branch block. Maximum (max), minimum (min) and mean QTc values were considered. QTc dispersion was calculated as: a) max QTc - min QTc (max-min); b) dispersion index (DI) = standard deviation of QTc/mean QTcx100. Patients groups were defined accordingly to: 1--the absence (group A1-35 patients) or the presence (group A2-20 patients) of CVA on 24 hours Holter monitoring; II--absence of cardioactive medication (group B1-20 patients) versus monotherapy with Am (group B3-10 patients), or beta B (group B4-15 patients), or CA (group B5-10 patients). Age, gender, type of HCM (asymmetric versus concentric) and echocardiographic fractional shortening were not different in the studied groups. RESULTS: [table: see text] CONCLUSIONS: 1. Maximum QTc interlead QTc dispersion are increased in patients with HCM that show CVA on Holter monitoring; 2. Amiodarone prolongs QTc but reduces QTc dispersion, while beta-blockers and calcium antagonists do not significantly change neither the duration nor the dispersion of ventricular repolarization.

Clinical and electrophysiologic characteristics in patients with Wolff-Parkinson-White pattern.

OBJECTIVES: (1) To obtain a relation between clinical and electrophysiologic characteristics in patients with Wolff-Parkinson-White pattern. To evaluate the atrial vulnerability for inducing atrial fibrillation and its relation to the electrophysiologic protocol phase. (3) To study the effects of flecainide on the treatment of induced sustained supraventricular arrhythmias. SETTING: Department of Cardiology at Santa Marta Hospital. METHODS: An electrophysiologic testing was performed in twenty-three consecutive patients aged from 14 to 55 years, with Wolff-Parkinson-White (WPW) pattern on ECG. Two groups of patients were considered: group I with 12 asymptomatic or nearly asymptomatic patients; group II with 11 symptomatic patients. The parameters studied were the anterograde effective refractory period of the accessory pathway, the number of patients with different types of supraventricular tachycardias (SVT), the relation between the stimulation protocol phase (scanning/DDT/burst) and the occurrence of atrial fibrillation, and the effects of the flecainide on the treatment of induced sustained supraventricular arrhythmias. RESULTS: Statistically significant differences were obtained between group I and II concerning the number of patients in whom induced atrial fibrillation with conduction by the accessory pathway and RR < or = 250 msec was found (0 vs 6, p = 0.0045). No differences were obtained among the anterograde refractory period, the induction of atrial fibrillation independently of the type of atrioventricular conduction, and the induction of atrioventricular reentrant tachycardia and or atrial flutter. The induction of atrial fibrillation was attained during the Scanning/DDT protocol phase in 7 patients in whom this arrhythmia was found with conduction by the accessory pathway and in 2 without preexcitation. All the induced sustained supraventricular arrhythmias were converted by intravenous flecainide. CONCLUSIONS: (1) Only the symptomatic patients have a high risk profile which suggest that electrophysiologic testing do not need to be performed in those with no symptoms. (2) As atrial vulnerability is higher in patients with induced atrial fibrillation and conduction by the accessory pathway, a more intensive ambulatory control seems to be necessary. (3) The results of intravenous flecainide administration on the treatment of sustained induced supraventricular arrhythmias, advocate its use during the electrophysiologic procedures in patients with ventricular preexcitation and WPW pattern.

Effects of diltiazem on myocardial ischemia in patients with coronary artery disease.

OBJECTIVES: To evaluate the effect of diltiazem on the characteristics of ischemic episodes detected by Holter monitoring in a group of patients with proven coronary artery disease. SETTING: Department of Cardiology, Santa Marta Hospital, Lisbon. METHODS: Eleven selected out-patients, aged 48 to 79 years, with transient ST-segmental depression on Holter monitoring and proven coronary artery disease, were submitted to a double-blind crossover placebo controlled study, during hospitalization. The total ischemic burden of each patient and an analysis of ischemic episodes were evaluated before and during the drug/placebo phase trial. Three groups of ischemic episodes were considered: group I constituted by 66 episodes found on basal Holter recording; group II by 28 episodes detected during placebo trial and group III by 12 episodes detected during diltiazem trial. RESULTS: A reduction of the number of ischemic episodes was predominantly observed with the diltiazem administration. Statistically significant differences were observed between basal and placebo groups and especially between basal and diltiazem groups concerning the mean maximum ST-segment depression (2.17 vs 1.80; p = 0.030 and 2.17 vs 1.54; p = 0.0091). Significant differences were also obtained between the above mentioned groups concerning the heart rate variation from the onset of ST-segment depression to its maximum depression (13.5 vs 9.69; p = 0.023 and 13.5 vs 2.91; p = 0.01) and from two minutes before the onset of ST-segment depression to its maximum depression (21.2 vs 12.67; p = 0.012 and 21.2 vs 8.75 p = 0.016). CONCLUSIONS: Diltiazem seems to reduce the number of ischemic episodes in patients with coronary artery disease, during hospitalization. The study of its effects on the characteristics of ischemia requires further investigation with a greater number of patients. The limitations of the present study, described in the discussion, must be taken into account in future pharmacological investigations with Holter monitoring.

[Contribution of Holter monitoring in the diagnosis of a case of Prinzmetal's angina]. / Contributo do registo de Holter para o diagnóstico de um caso de angina de prinzmetal.

Prinzmetal angina is a peculiar kind of angina pectoris, in which Holter monitoring has been particularly useful for diagnosis. In this paper it is reported a 56 years old male patient with coronary artery spasm induced during coronary arteriography in which the Holter electrocardiography was of most importance for decision making.

[Dilated myocardiopathies: the relationship between the degree of cardiac dysfunction and ventricular arrhythmias. A clinical follow-up]. / Miocardiopatias dilatadas: relação entre o grau de disfunção cardíaca e arritmias ventriculares. Seguimento clínico.

STUDY OBJECTIVE: Characterization of the arrhythmic profile of idiopathic dilated cardiomyopathy (DMC); Evaluation of the relation of complex ventricular ectopy and cardiac dysfunction; Clinical outcome. PATIENTS: We studied 20 patients (P) with idiopathic DCM, 15 males P and 5 female P, mean age 51.3 +/- 17.4 years (between 17 and 75 years). MATERIAL AND METHODS: 24-hours Holter study and left cardiac catheterization with ventriculography were performed. Patients were followed at the consults. RESULTS: We detected in the Holter study the presence of ventricular ectopy in 19 P (95%). Nine P had complex ventricular arrhythmias (45%), 10 P had simple ventricular arrhythmias (50%) and 1 P had no ventricular arrhythmia (5%). The mean left ventricular ejection fraction was 28.6 +/- 14.1% (12 to 44%). Two groups were defined based on the severity of left ventricular dysfunction: Group I with 12 P and Group II with 8 P. In Group I, 8 P had complex ventricular ectopy and, in Group II, 1 P had complex ventricular ectopy (p < 0.05). Comparing mean left ventricular ejection fraction in the two groups of arrhythmias (simple and complex), 33.9 +/- 12.5% and 22.1 +/- 13.8%, we found out a statistically significant difference (p < 0.05). After an eight to thirty six months of follow-up, a greater number of cardiac events (mortality, transplant) were detected in the groups of complex arrhythmia and of more severe cardiac dysfunction. CONCLUSIONS: We conclude that there is a high frequency of ventricular arrhythmias in this group of patients with idiopathic DCM. Complex ventricular arrhythmias were more frequently associated to more severe left ventricular dysfunction. The number of cardiac events at follow-up was higher in patients with complex ventricular arrhythmias and in those with more depressed cardiac function.

Coronariographic significance of heart rate variation related to ischemic episodes in patients undergoing peripheral vascular surgery.

OBJECTIVES: To evaluate the characteristics of myocardial ischemia during daily life and their coronariographic significance in a group of patients with proven coronary artery disease undergoing peripheral vascular surgery. SETTING: Department of Cardiology--Central Hospital--Lisbon. METHODS: In 14 patients undergoing peripheral vascular surgery and in whom coronariography revealed coronary significative lesions, Holter monitoring was performed during a 24-hour period. Two groups of ischemic episodes were considered: Group A constituted by 44 episodes detected in patients with left main or three vessel disease and group B by 12 episodes detected in patients with one ot two vessel disease. In each group the ischemic parameters were studied. RESULT: The incidence of myocardial ischemia was 64%. Statistically significant differences were observed between group A and B concerning the mean heart rate variation from two minutes before the onset of ST-segment depression to its onset (2.39 bpm vs 8.75 bpm; p < 0.05), from the onset of ST-segment depression to its maximal depression (4.43 bpm vs 16.67 bpm; p < 0.001) and from two minutes before St-segment depression to its maximal depression (6.82 bpm vs 25.4 bpm; p < 0.00001). No differences were found in duration and maximal ST-segment depression. CONCLUSION: Particular characteristics of heart rate variation related to the ischemic episodes seem to have a relation with the severity of coronary artery disease in patients undergoing peripheral vascular surgery.

[Multiple thromboembolism associated with anti-thrombin III deficiency]. / Tromboembolias múltiplas associadas a défice de anti-trombina III.

Congenital deficiency of antithrombin III is considered as one serious primary hypercoagulable state. The authors present a case of deficiency of antithrombin III in a 28 years old young male, with aortic valve disease and several thromboembolic events. When discussing their diagnostical and therapeutical aspects they call the attention to the need for investigation of the situations in which thrombophilia presents with recurrent venous and arterial thrombosis.

[Arrhythmic profiles evaluated by Holter's technique in sick sinus syndrome]. / Perfis arrítmicos avaliados por método de Holter na doença do nódulo sinusal.

OBJECTIVES: The aim of this study was to evaluate in a group of patients with sick sinus syndrome: 1) Characteristics of arrhythmia on Holter monitoring. 2) Value of Holter monitoring to select patients for pacemaker implantation. SETTING: Department of Cardiology in a Central Hospital. METHODS: In 40 patients (27 men and 13 women, aged 37 to 83 years) Holter monitoring during a 24-hour period was performed. According to the arrhythmia profiles four groups of patients were considered: group A--with severe sinus bradycardia; group B--with sinus bradycardia associated to sinoatrial exit block or to sinus pauses; group C--characterized by the bradycardia-tachycardia syndrome and group D--defined by the finding of atrial fibrillation with a slow ventricular response. Symptoms and the presence of structural heart disease were evaluated. RESULTS: In this patients population, 24 patients had coronary artery disease and/or hypertensive heart disease. A severe sinus bradycardia was found in 14 patients (group A) and in other 11 patients it was accompanied by sinoatrial exist block of sinus pauses (group B); 12 patients had the bradycardia-tachycardia syndrome (group C) and periods of atrial fibrillation with a slow ventricular response were found in 3 other patients (Group D). Nonspecific clinical pattern was observed in this population. CONCLUSIONS: Holter monitoring was important to the diagnosis of sick sinus syndrome and for posterior definitive pacemaker implantation. Coronary artery disease and/or hypertensive heart disease were the main pathologies found in this study, being the severe sinus bradycardia and the bradycardia-tachycardia syndrome the principal manifestations of the sick sinus syndrome.

Incidence, characteristics and coronariographic significance of myocardial ischemia during daily life in patients with angina pectoris.

OBJECTIVES: To evaluate the incidence, characteristics and angiographic significance of myocardial ischemia detected on Holter monitoring in a group of patients with stable angina pectoris. SETTING: Department of Cardiology of a Central Terciary Hospital. METHODS: In 24 patients (pts) with stable angina pectoris and proven coronary artery disease (11 pts with left main or three vessel disease; 13 pts with one or two vessel disease), a 24 hour Holter monitoring was performed. Two groups of ischemic episodes were considered: Group I with 65 ischemic episodes detected in pts with left main or three vessel disease and group II constituted by 17 ischemic episodes detected in pts with one or two vessel disease. RESULTS: The incidence of myocardial ischemia was 91% in pts with left main or three vessel disease and 46% in pts with one or two vessel disease. Statistically significant differences were seen between group I and II concerning the mean heart rate variation from two minutes before onset of ST-segment depression to its onset (3.5 bpm vs 7.4 bpm; p less than 0.05) and from the onset of ST-segment depression to its maximal depression (6.5 bpm vs 15 bpm; p less than 0.000001). CONCLUSIONS: The presence of myocardial ischemia and some of its characteristics on Holter monitoring seem to have a relation with the severity of coronary artery disease in patients with stable angina pectoris.

[Dysrhythmic profile and clinical aspects in a population of 23 patients with hypertrophic cardiomyopathy]. / Perfil disrítmico e aspectos clínicos numa população de 23 doentes com cardiomiopatia hipertrófica.

OBJECTIVES: To evaluate: 1. The incidence and characteristics of ventricular arrhythmias on Holter monitoring and their relation to the clinical, functional and morphological aspects. 2. The survival and therapeutical efficiency of amiodarone in a subgroup of patients with ventricular tachycardia. SETTING: Department of Cardiology in a General Hospital. METHODS: 23 patients (pts) aged 19 to 74 years with an echocardiographic diagnosis of cardiomyopathy were studied during a four year period by 24 hours Holter monitoring. Ventricular arrhythmias were defined according the Lown classification. Patients were classified according to: obstructive or nonobstructive hypertrophy (funtional groups, 11 and 12 pts respectively), asymmetric hypertrophy of the septum or ventricular concentric hypertrophy or apical hypertrophy (morphological groups, 18, 3 and 2 pts respectively). They were also classified according medical therapy (pharmacological with B-blockers or calcium antagonists and nonpharmacological groups, 7 and 16 pts respectively). RESULTS: the incidence of severe ventricular arrhythmias was 57.1% and 62.5% in the pharmacological and nonpharmacological groups respectively. In both obstructive and nonobstructive forms, severe ventricular arrhythmias were also found (7/8 pts in each group). 12 pts with asymmetric hypertrophy of the septum and 2 pts with the concentric hypertrophic form also had severe ventricular arrhythmias. Five pts with nonsustained ventricular tachycardia have been submitted to oral amiodarone therapy in a dosage of 200 mg daily. All these pts are alive (follow-up ranged from 15 to 54 months) and in five no significant ventricular arrhythmias have been detected on serial Holter records. CONCLUSIONS: the incidence of ventricular arrhythmias was high in this patients population and no definitive relation could be found between the severity of ventricular arrhythmias and the previous described groups. Meanwhile, classic medical therapy seems not to alter the incidence and the characteristics of ventricular arrhythmias. On other hand, amiodarone therapy seems to abolish ventricular tachycardia in a large percentage of cases and no death occurred during a significant period of time (maximal 54 months).

[Clinical and hemodynamic efficacy of enalapril in severe congestive heart failure]. / Eficácia clínica e hemodinâmica do enalapril na insuficiência cardíaca congestiva grave.

OBJECTIVES: Evaluate the clinical and hemodynamic efficacy of enalapril in the treatment of severe congestive heart failure, refractory to the classic therapeutics with diuretics and digitalis. SETTING: Hospitalized patients (pts) of a cardiac department. MATERIAL AND METHODS: 10 pts with a mean age of 57.8 years in whom a Swan-Ganz catheter was placed for 72 hours to monitor the right pressures and cardiac output, with regular control of arterial blood pressure and cardiac frequency. Low doses of enalapril (2.5 mg) were utilized at the start of the treatment and this dose was readjusted depending on the clinic and hemodynamic parameters. RESULTS: the 10 pts had the following characteristics: Basal-mean pulmonary arterial pressure (PAP) 34.1 mmHg, Pulmonary wedge pressure (PWP) 21.1 mmHg, cardiac output (CO) 4.8 l/min, cardiac index (CI) 2.8 l/min/m2. After 72 hours with enalapril treatment, these measurements were: PAP-23.8 mmHg, PWP-12.6 mmHg, CO-5.2 l/min and Cl-3.0 ll/min/m2. These differences were statistically significant. With a follow-up of 18.4 months, there was also a clinical improvement; of the 4 pts in class III, 2 moved to class II and 2 to class I; the 4 pts in class IV 4 moved to class II; two pts had died. CONCLUSIONS: In severe heart failure, the addition of enalapril to the classic therapy has allowed the immediate improvement of the clinical and hemodynamic indexes and this improvement was maintained in the follow-up period.