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E Sosa

Publications and source records attributed to E Sosa.

At least 37 records · Page 2Linked to original sources
PubMed1996

In vivo detection of Trypanosoma cruzi antigens in hearts of patients with chronic Chagas' heart disease.

The heart is the most commonly affected organ in chronic Chagas' disease, and lymphocytic myocarditis is often observed. However, the pathogenesis of chronic Chagas' heart disease is controversial. The purpose of this study was to determine whether in vivo T. cruzi antigens could be detected in hearts from patients with chronic Chagas' disease and to investigate whether a correlation between these antigens and the intensity of myocardial inflammation exists. We studied 16 patients with chronic Chagas' heart disease. Ten patients had severely impaired left ventricular function and refractory heart failure, and six had episodes of sustained ventricular tachycardia without severe left ventricular dysfunction. Eight patients underwent magnetic resonance imaging with gadolinium enhancement to guide endomyocardial and surgical biopsies to sites with more intense inflammatory processes. Myocardial specimens were studied with immunohistochemical techniques by using rabbit anti-T. cruzi immune serum to detect the presence of T. cruzi antigen. All patients had evidence of some myocarditis in at least one myocardial fragment. T. cruzi antigen was detected in 11 (69%) patients. T. cruzi antigens were detected in 10 (71%) of 14 regions with histopathologic evidence of moderate or severe myocarditis. In contrast, T. cruzi antigens were detected in 3 of 18 regions with only mild or absent myocarditis. There was a statistically significant correlation between the presence of T. cruzi antigens and moderate or severe myocarditis (chi-square = 5.169, p = 0.023). The results of this in vivo study demonstrate that T. cruzi antigens are frequently detected in chronic Chagas' heart disease. In addition, there is an association between the intensity of the inflammatory process and the presence of T. cruzi antigens. The presence of the T. cruzi antigen and its correlation with the severity of myocardial inflammatory process provide strong supportive evidence for the role of T. cruzi even in the chronic forms of Chagas' heart disease.

Adult↗
PubMed1996

Electrocardiographic identification of mid-septal accessory pathways in close proximity to the atrioventricular conduction system.

In order to identify ECG characteristics of overt mid-septal accessory pathways (APs) predictive of close proximity to the AV conduction system we analyzed data from patients who underwent successful RF catheter ablation of a mid-septal AP. Mean patient age was 31 +/- 16 years, and 13 were male. The 40 degrees right anterior oblique view was used to divide the mid-septal area into 3 zones: 1 (anterior portion); 2 (intermediate); and 3 (posterior portion). The 12-lead ECG was analyzed with regard to delta wave polarity and R/S transition in the precordial leads. The findings from patients ablated at zone 3 were compared to those at zones 1 and 2. All patients had a positive delta wave in the leads I, II, aVL, and negative delta wave in the leads III and aVR. The R/S transition occurred in lead V2 in 80% of patients. The delta wave in lead aVF was the only ECG characteristic that correlated with the AP ablation zone. Six of 8 patients ablated at zone 3 had a negative delta wave in lead aVF while 6 out of 7 patients ablated at zone 1 or 2 had a positive or isoelectric delta wave in lead aVF (P = 0.03). A positive or isoelectric delta wave in lead aVF identifies mid-septal AP in close proximity to the AV conduction system.

Adolescent↗
PubMed1996

A new technique to perform epicardial mapping in the electrophysiology laboratory.

INTRODUCTION: A possible epicardial site of origin may be the reason for unsuccessful endocardial application of radiofrequency energy to control recurrent ventricular tachycardia. This study tests the feasibility and safety of a new epicardial mapping technique in patients with Chagas' disease and recurrent ventricular tachycardia. METHODS AND RESULTS: Epicardial mapping was performed through a pericardial puncture as an epidural introducer needle was advanced into the pericardial space under fluoroscopic guidance. Medium contrast was injected to demonstrate the position of the needle tip, and a guidewire was introduced until its tip lay within the pericardial space. A 8-French Hemaquet was advanced and 4-mm deflectable tip catheter introduced into the pericardial sac to map the right and left ventricular epicardium. Transthoracic echocardiographic monitoring was performed on the day of the procedure and on the day of hospital discharge. The pericardial space was reached in all patients with no complications. Electrophysiologic data suggesting the existence of an epicardial circuit was found in one patient. No complications occurred during the hospitalization period. CONCLUSION: Epicardial mapping can be safely performed through a pericardial puncture in the electrophysiology laboratory.

Body Surface Potential Mapping↗
PubMed1995

A fast and reliable algorithm to localize accessory pathways based on the polarity of the QRS complex on the surface ECG during sinus rhythm.

BACKGROUND: Many criteria have been published to localize accessory pathways from the 12-lead ECG during sinus rhythm. This study analyzed whether the localization of an accessory pathway could be predicted by using the polarity of the QRS complex during sinus rhythm on the surface ECG, instead of the delta wave polarity as used in many reports. METHODS: The ECGs of 140 patients with an overt and single accessory pathway were evaluated. Eight localizations were taken into account. The precise location was previously known from successful radiofrequency ablation sites. RESULTS: In 128 patients (92%), the new algorithm allowed an accurate diagnosis of the site of implantation of the accessory pathway. CONCLUSION: Analysis of the polarity of the QRS complex on five electrocardiographic leads provides an easy, fast and reliable way to localize accessory pathways during sinus rhythm.

Algorithms↗
PubMed1994

Clinical and electrophysiologic features of syncope in chronic chagasic heart disease.

INTRODUCTION: Syncope in patients with chronic Chagasic heart disease (CCHD) is a frequent but poorly studied problem. METHODS AND RESULTS: Fifty-three patients with CCHD and recurrent syncope were followed for 2 to 127 months. They were classified into the following groups: G-I (n = 15) without inducible ventricular tachycardia (VT) and normal HV interval; G-II (n = 17) with only inducible VT; G-III (n = 11) with only an abnormal HV interval; and G-IV (n = 10) with both an inducible VT and an abnormal HV interval. Empiric pharmacologic therapy was given in G-I; pharmacologic therapy guided by electrophysiologic study in G-II; atrioventricular pacing in G-III; and empiric pharmacologic with atrioventricular pacing in G-IV. Age and sex were similar among groups; New York Heart Association Functional Class I symptoms were more prevalent (P = 0.0001) in G-I. The ejection fraction by echocardiography was higher in G-I (P = 0.0122). The density of premature ventricular complexes by Holter monitoring was similar among groups. The complexity of premature ventricular complexes by Holter was significantly higher in G-II (P = 0.0270); this variable, analyzed from the exercise electrocardiogram, was not different among groups. All deaths were sudden, prevalence was higher in G-II and absent in G-III, and recurrence of syncope was similar among groups. CONCLUSION: The most probable causes of recurrent syncope were VT (43%) with poor prognosis, and paroxysmal atrioventricular block (21%) with a favorable prognosis. Absence of congestive heart failure, complexity of premature ventricular complexes by Holter, and absence of intraventricular heart block showed statistical correlation with normal electrophysiologic study, inducible VT, and normal HV interval, respectively.

Adult↗
PubMed1994

[The pseudo-pacemaker syndrome].

We describe three cases of the pseudo-pacemaker syndrome. One of them due to selective fast pathway fulguration of atrioventricular nodal reentrant tachycardia and two others have occurred in spontaneous form. All cases were related with the presence of first-degree atrioventricular block and sinus node tachycardia. The treatment was done with complete atrioventricular block induction catheter ablation and permanent pacemaker implantation in two patients. In conclusion, the procedure of radiofrequency ablation to control AV nodal reentry tachycardia must preserve the fast nodal pathway in order to avoid the pseudo-pacemaker syndrome and this syndrome can spontaneously occur and must be considered during investigation of etiology of syncope.

Adult↗
PubMed1994

Arrhythmias and sudden death after dynamic cardiomyoplasty.

BACKGROUND: The main causes of death in patients with severe cardiomyopathy are progressive heart failure and sudden death. The influence of cardiomyoplasty on the incidence of sudden death and arrhythmias in patients with cardiomyopathy remains unclear. The aim of this study was to investigate the occurrence of arrhythmias and sudden death after cardiomyoplasty. METHODS AND RESULTS: We studied 32 patients (26 male, 6 female; mean age, 48 +/- 12 years) who submitted to cardiomyoplasty for treatment of heart failure in New York Heart Association (NYHA) class III (n = 24) or class IV (n = 8). The etiology was idiopathic dilated cardiomyopathy in 27 patients, ischemic heart disease in 3 patients, and Chagas' heart disease in 2 patients. Patients were routinely studied before and every 6 months after cardiomyoplasty by means of radioisotopic angiography and 24-hour Holter monitor recordings. There were no operative or immediate postoperative deaths. During the postoperative period, 5 patients presented with acute atrial fibrillation and 1 had an episode of sustained ventricular tachycardia. All episodes were successfully treated with intravenous antiarrhythmic drugs or cardioversion. During follow-up (from 2 to 66 months), 15 patients died from sudden death (n = 5) or progressive heart failure (n = 10). Survival rates at 1, 2, and 4 years were 79.9 +/- 7%, 62.5 +/- 9.7% and 35 +/- 12.1%, respectively. At 6-month follow-up, NYHA functional class improved from 3.2 +/- 0.4 to 1.7 +/- 0.6 (P = .001) and left ventricular ejection fraction increased from 19.8 +/- 3.3% to 24 +/- 8.2% (P = .004). The mean values per day of premature ventricular complexes (PVCs) and episodes of nonsustained ventricular tachycardia (NSVT) did not change statistically. The mean number of PVCs per 24 hours before and at 6, 12, 24, 36, and 48 months after surgery were 126 +/- 44, 96 +/- 33, 90 +/- 29, 81 +/- 35, 71 +/- 35, and 59 +/- 48. The mean number of episodes of NSVT per 24 hours before and at 6, 12, 24, 36, and 48 months after surgery were 3.3 +/- 1.3, 1.9 +/- 0.5, 1.3 +/- 0.5, 1 +/- 0.5, 1.5 +/- 1.1, and 0.6 +/- 0.5, respectively. With respect to analysis of the idiopathic dilated cardiomyopathy subgroup, there also were no significant differences in the incidences of pre- and postoperative arrhythmias. CONCLUSIONS: Despite NYHA functional class and left ventricular function improvements observed after cardiomyoplasty, the incidence of arrhythmias did not change, and sudden death was an important finding mainly in late follow-up. The problem of sudden death after cardiomyoplasty, the mechanism that produces it, and the means to prevent it remain critical areas for future research.

Arrhythmias, Cardiac↗
PubMed1994

[Arrhythmias following orthotopic heart transplantation].

PURPOSE: To correlate the incidence of arrhythmias to the degree of allograft rejection on endomyocardial biopsy. METHODS: Seventeen patients who underwent orthotopic heart transplantation were submitted to ambulatory Holter monitoring 24h prior to endomyocardial biopsy. The biopsy results were compared to Holter monitoring results. RESULTS: The mean study period was 252 +/- 166 days (15 to 515). We found a high incidence of ventricular premature beats (> 70%), except in patients with severe rejection (25%), but there was no statistically significant difference between the groups with no rejection, mild and moderate rejection. Atrial premature beats were more common in patients with mild and moderate rejection (53% and 70%, respectively) when compared to patients with no rejection (33%) and patients with severe rejection (9%), (p < 0.05). Sinus bradycardia was present in 50% of patients with severe rejection, but only in 9% of moderate, 3% of mild and 5% of the patients with no rejection (p < 0.05). CONCLUSION: Supraventricular tachycardia and atrial premature beats are related to moderate rejection. Ventricular premature beats are not related to degree of rejection. Sinus bradycardia occurring in the first year after transplantation should suggest severe cardiac allograft rejection.

Arrhythmias, Cardiac↗
PubMed1993

Complications of laparoscopic pelvic lymph node dissection.

Intraoperative and postoperative complications were assessed in the first 372 patients undergoing laparoscopic pelvic lymph node dissection at 8 medical centers. In 16 patients laparoscopic node dissection could not be completed due to patient body habitus or technical difficulties. Of these aborted procedures 14 occurred during the initial 8 dissections at each institution. A total of 55 complications (15%) occurred: 14 were noted in the intraoperative and 41 in the postoperative period. Of these patients 13 required open surgical intervention for the treatment of a complication. Complications included vascular injury (11 patients), viscus injury (8), genitourinary problems (10), functional/mechanical bowel obstruction (7), lower extremity deep venous thrombosis (5), infection/wound problem (5), lymphedema (5), anesthetic complications (2) and obturator nerve palsy (2). Based on our experience, there is a significant learning curve associated with performing laparoscopic pelvic node dissection. However, with experience and adherence to laparoscopic surgical principles, the risk of complications may be minimized.

Adenocarcinoma↗
PubMed1993

[Catheter ablation of accessory pathways with low energy. Results in 40 consecutive patients].

PURPOSE: To evaluate the results of direct current catheter ablation of accessory pathways by mean of a new low energy power source. METHODS: Catheter ablation was performed in 40 consecutive patients (23 male, mean age 31 +/- 11 years) with accessory atrioventricular pathways (AP) using a low energy DC power source. The electrophysiologic study and AP ablation were performed in the same procedure by endocardial approach using non-deflectable 6F bi, tri, or quadripolar electrodes. RESULTS: AP was located at left free wall (LFW) in 22 patients (55%), posteroseptal (PS) in 11 patients (27.5%), anteroseptal (AS) in 5 patients (12.5%) and right lateral (RL) in 2 patients (5.0%). A mean of 7.7 +/- 7 catodal shocks of 5-75 (20) joules (J) was delivered in 1.45 +/- 7 sessions, with a mean cumulative energy of 178 +/- 213J per patient. The mean values of number of shocks, number of sessions and cumulative energy per patient were lower in LFW AP ablation than in other positions (5 +/- 4 x 11 +/- 8 - p = 0.008; 1.1 +/- 0.3 x 1.8 +/- 0.9 - p = 0.008 and 118 +/- 150 x 260 +/- 245 - p = 0.03). The mean CK-MB rise was 18.5 +/- 7.8U/1. Three patients (7.5%) presented hemopericardium after PS AP ablation and in 1 patient (2.5%), a PS AP (paranodal pathway) ablation resulted in total atrioventricular block. During a follow-up of 9.5 +/- 4 months AP was absent in 28 (70%) patients; 18/22 (82%) with LFW AP, 6/11 (54%) with PS AP, 3/5 (60%) with AS AP and 1/2 (50%) with RL-AP, (p = 0.10). CONCLUSION: Low energy DC ablation is effective for AP ablation. The results are related with AP position.

Adolescent↗
PubMed1992

Ventricular arrhythmias induced by programmed ventricular stimulation after uncomplicated myocardial infarction.

The aim of this study was to correlate the occurrence of ventricular dysrhythmias induced by programmed ventricular stimulation and sudden cardiac death (SCD) after a first episode of acute myocardial infarction (AMI). Twenty-seven consecutive male patients aged fifty-four +/- six (forty-seven to seventy) years were studied prospectively. Thirty days after AMI, patients were submitted to coronary arteriography and programmed ventricular stimulation with the S2-S3-S4 protocol. Noninvasive assessments, including Holter monitoring, ECG stress test, and radionuclide ejection fraction, were also repeated six and twelve months after AMI. Ventricular dysrhythmias were induced in all patients. According to such response, patients were divided into three groups: (1) repetitive ventricular response (n = 9); (2) nonsustained ventricular tachycardia (n = 8); and (3) sustained ventricular tachycardia (n = 10). All patients consistently developed complex ventricular dysrhythmias at Holter monitoring and ECG stress test. One patient from group 2 suffered SCD and another presented a syncope. Similarly, in group 3, 2 patients suffered SCD, 1 during a documented episode of recurrent AMI. Except for 1 patient, radionuclide ejection fraction remained unchanged throughout the study in all cases. SCD was also unrelated to the presence and type of dysrhythmias at noninvasive evaluation. Therefore, the type of ventricular dysrhythmia induced by the S2-S3-S4 protocol has no correlation with late SCD in patients with a first AMI and preserved ejection fraction.

Adult↗
PubMed1992

[The surgical treatment of nodal reentry tachycardia. The late results].

PURPOSE: To analyze the long-term results of surgical treatment of atrioventricular nodal reentrant tachycardia (AVNT). METHODS: From March 1987 to March 1990, 20 patients with AVNT were submitted to surgical therapy, 14 female, aged 12 to 70 (42.8 +/- 17) years. All presented crisis of AVNT from 6 months to 60 (18.4 +/- 15.9) years. Ten of them had syncope or near syncope and two with cardiac arrest during reversion of AVNT with antiarrhythmic drugs. They used 1 to 6 (3.75 +/- 1.45) antiarrhythmic drugs before surgery. The electrophysiologic study (EPS) showed the common form of AVNT in all cases. The surgical procedure was anatomically directed to the posterior area of the AV node. Programmed atrial stimulation (PAS) were applied on 18 patients after surgery. The long-term results were analysed by clinical evaluation, EPS and Holter when they were necessary. RESULTS: The postoperative PAS was done in 18 patients and did not induce any AVNT, even after atropine IV. The PR interval was 153 +/- 50 ms before and 152 +/- 38 ms after surgery (p > 0.05). During follow up (26 +/- 10 m) there were not AVNT recurrence. Two patients developed chronic atrial fibrillation after 24 months of surgery. CONCLUSION: The perinodal dissection technique used was safe and successful to treat AVNT, preserving AV nodal conduction.

Adolescent↗
PubMed1992

[The late results of fulguration of the atrioventricular node using high-energy shocks in patients with supraventricular tachycardias].

PURPOSE: To evaluate the long-term efficacy and safety at long term after atrioventricular junction fulguration (complete AV block induction, using high energy shocks, to control drug-resistant supraventricular tachyarrhythmias. METHODS: Twenty-eight patients, 17 (60.7%) men, with mean age 48.1 years, were submitted to one up to six ablation sessions with high energy shocks. The total delivered energy per patient was 1304 +/- 868 J. Each shock ranged from 100 to 400 J. RESULTS: After 12 months, at least, 60.6% of patients were in complete atrioventricular block; three (10.8%) were asymptomatic without complete AV block, and in five (17.8%) the ablation was unsuccessful. CONCLUSION: AV junction ablation with high energy shocks is safe and efficient in long-term follow-up.

Adult↗
PubMed1992

Recurrent ventricular tachycardia associated with postinfarction aneurysm. Results of left ventricular reconstruction.

Left ventricular reconstruction was used to control recurrent ventricular tachycardia in 19 patients (16 male), mean age of 56 years, with postinfarction anteroseptal aneurysms. The "origin" of recurrent ventricular tachycardia was not determined because the ventricular tachycardia induced by programmed stimulation produced hemodynamic deterioration in all patients. The average ejection fraction was 30.7% +/- 10.1%. In the left ventricular reconstruction technique, the plication of the aneurysmal septum and the reduction of the orifice of the left ventricular cavity after aneurysmal resection with a purse-string suture appear important to prevent the functioning of the reentry circuits. There was one death in the immediate postoperative period. The mean ejection fraction was 47.8% +/- 8.1% (p less than 0.001). The postoperative programmed stimulation induced ventricular tachycardia in only one patient. There were two late deaths. The other 16 patients are asymptomatic (five with antiarrhythmic drugs) in functional class I and without recurrence of ventricular tachycardia. Left ventricular reconstruction is an acceptable technique that changes the spatial orientation in eventual tachycardia circuits. Hence this technique is an alternative for long-term control of the right ventricular tachycardia associated with postinfarction anteroseptal aneurysm without previous electrophysiologic mapping.

Bundle-Branch Block↗
PubMed1991

Incessant ectopic atrial tachycardia and sudden death.

A patient with refractory and incessant ectopic atrial tachycardia (IEAT) is reported in whom it was possible to document, during ECG (Holter) the occurrence of aborted sudden death by spontaneous ventricular fibrillation (VF). Following the second of two attempts at surgical ablation of the origin of the IEAT, the patient has been asymptomatic without antiarrhythmic drugs and in sustained sinus rhythm for 24 months. Although we cannot exclude the residual action of amiodarone and flecainide (proarrhythmia) or the residual peripartum cardiomyopathy it is probable that the observed VF was a true complication of a cardiomyopathy induced by a chronically increased heart rate (HR). Although unclear, this VF might be considered as a form of adrenergic-dependent long QT syndrome due to early afterdepolarization in the presence of predisposing myocardial conditions.

Adult↗
PubMed1990

[Predictive value of programmed ventricular stimulation after myocardial infarction].

PURPOSE: To find out whether is there a relation between electrophysiology laboratory ventricular arrhythmias through programmed ventricular stimulation, and the occurrence of relevant clinical events, particularly, sudden death, in patients victims of first episode of myocardial infarction. PATIENTS AND METHODS: Twenty-seven patients (all males) who suffered non-complicated first myocardial infarction, with age varying from 47 to 70 (mean 54 +/- 6) years were prospectively and consecutively studied. Upon consent, patients were at first submitted to conventional cinecoronaryography and to programmed ventricular stimulation utilizing the S2, S3, S4 protocol, 30 days after infarction. Moreover, patients were submitted to continuous electrocardiographic (Holter system), exercise test, and radioisotopic studies for left ventricle ejection fraction (phase I). The last three studies were subsequently repeated at 6 and 12 months (phases II and III), respectively. RESULTS: All patients had ventricular arrhythmia induced, and according to the kind of response, patients were grouped into: group I--repetitive ventricular response, RVR, nine (33.5%) patients; group II--non sustained ventricular tachycardia. NSVT, eight (29.5%) patients; group III--sustained ventricular tachycardia SVT, ten (37%) patients. The patients of three groups, when submitted to electrocardiographic exercise test and Holter system studies, revealed complex arrhythmias in all phases. One patient of group II suddenly died at home, and another was injured with syncope, whereas in group III, two suddenly died, one at home and the other at the admission to the hospital, after an acute myocardial infarction. All patients but one of group I, who had a non-fatal reinfarction, showed preserved ventricular function. CONCLUSION: Holter system and electrocardiographic exercises test revealed complex dysrhythmia in the tree phases of the study, independently of the induced response; C--Holter system and electrocardiographic exercise test studies revealed no relation. between sudden death and the kind of ventricular induced response or complex arrhythmia. Ventricular arrhythmia induced with S2, S3 and S4 protocol in patients with preserved ventricular function seems to indicate results without predictive value for cardiac sudden death.

Aged↗