Applicability of the PAINESD risk score for 30-day mortality prediction post ventricular tachycardia catheter ablation in Chagas disease.

PURPOSE: The PAINESD risk score was developed in 2015 as a tool to stratify the risk of acute hemodynamic decompensation during ventricular tachycardia (VT) ablation in structural heart disease patients and further then used for post procedure 30-day mortality prediction. The original cohort however did not include Chagas disease (ChD) patients. We aim to evaluate the relevance of the score in a ChD population. METHODS: The PAINESD risk score gives weighted values for specific characteristics (chronic obstructive pulmonary disease, age > 60 years, ischemic cardiomyopathy, New York Heart Association [NYHA] functional class 3 or 4, ejection fraction less than 25%, VT storm, and diabetes). The score was applied in a retrospective cohort of ChD VT ablations in a single tertiary center in Brazil. Data were collected by VT study reports and patient record analysis at baseline and on follow-up. RESULTS: Between January 2013 and December 2018, 157 VT catheter ablation procedures in 121 ChD patients were analyzed. Overall, 30-day mortality was 9.0%. Multivariate analysis correlated NYHA functional class (HR 1.78, 95% CI 1.03-3.08, P 0.038) and the need for urgent surgery (HR 31.5, 95% CI 5.38-184.98, P < 0.001), as well as a tendency for VT storm at presentation (HR 2.72, 95% CI 0.87-8.50, P 0.084) as risk factors for the primary endpoint. The median PAINESD risk score in this population was 3 (3-8). The area under the receiver operating characteristic (ROC) curve was 0.64 (95% CI 0.479-0.814). CONCLUSIONS: The PAINESD risk score did not perform well in predicting 30-day mortality in ChD patients. Pre-procedure NYHA functional class and the need for urgent surgery due to refractory pericardial bleeding were independently associated with increased 30-day mortality. Prospective studies are needed to take final conclusions in Chagas disease when using PAINESD score.

Transthoracic epicardial catheter ablation to treat recurrent ventricular tachycardia.

Nonsurgical epicardial transthoracic catheter ablation is a minimally invasive procedure that has proven to be efficacious for the treatment of ventricular tachycardia (VT). The usefulness of this technique depends on the prevalence of epicardial circuits, which seem more frequent in Chagasic than post-myocardial infarction VT. This approach is limited by concern regarding the potential adverse effects of radiofrequency (RF) ablation on the coronary arteries. However, the effects of RF ablation delivered in the vicinity of a major coronary artery are limited to the medial artery. Severe intimal hyperplasia and intravascular thrombosis may occur only when RF ablation is delivered above the artery. Moreover, susceptibility to damage is inversely proportional to the vessel size. Coronary artery injury is an uncommon (< 1%) complication that could be prevented by a coronary angiogram prior to ablation. Hemopericardium, another predictable complication occurring in 10% of patients, can be easily controlled in the electrophysiology laboratory.

Diagnostic value of the tilt-table test for the assessment of syncope in children and adolescents.

OBJECTIVE - To assess the diagnostic value, the characteristics, and feasibility of tilt-table testing in children and adolescents. METHODS - From August 1991 to June 1997, we retrospectively assessed 94 patients under the age of 18 years who had a history of recurring syncope and presyncope of unknown origin and who were referred for tilt-table testing. These patients were divided into 2 groups: group I (children) - 36 patients with ages ranging from 3 to 12 (mean of 9.19+/-2.31) years; group II (adolescents) - 58 patients with ages ranging from 13 to 18 (mean of 16.05+/-1.40) years. We compared the positivity rate, the type of hemodynamic response, and the time period required for the test to become positive in the 2 groups. RESULTS - The positivity rates were 41.6 % and 50% for groups I and II, respectively. The pattern of positive hemodynamic response that predominated in both groups was the mixed response. The mean time period required for the test to become positive was shorter in group I (11.0+/-7.23 min) than in group II (18.44+/-7.83 min). No patient experienced technical difficulty or complications. CONCLUSION - No difference was observed in regard to feasibility, positivity rate, and pattern of positive response for the tilt-table test in children and adolescents. Pediatric patients had earlier positive responses.

Pulmonary vein stenosis complicating catheter ablation of focal atrial fibrillation.

INTRODUCTION: A recently described focal origin of atrial fibrillation, mainly inside pulmonary veins, is creating new perspectives for radiofrequency catheter ablation. However, pulmonary venous stenosis may occur with uncertain clinical consequences. This report describes a veno-occlusive syndrome secondary to left pulmonary vein stenosis after radiofrequency catheter ablation. METHODS AND RESULTS: A 36-year-old man who experienced daily episodes of atrial fibrillation that was refractory to antiarrhythmic medication, including amiodarone, was enrolled in our focal atrial fibrillation radiofrequency catheter ablation protocol. The left superior pulmonary vein was the earliest site mapped, and radiofrequency ablation was performed. Atrial fibrillation was interrupted and sinus rhythm restored after one radiofrequency pulse inside the left superior pulmonary vein. Atrial fibrillation recurred and a new procedure was performed in an attempt to isolate (26 radiofrequency pulses around the ostium) the left superior pulmonary vein. Ten days later, the patient developed chest pain and hemoptysis related to severe left superior and inferior pulmonary veins stenosis. Balloon angioplasty of both veins was followed by complete relief of symptoms after 2 months of recurrent pulmonary symptoms. The patient has been asymptomatic for 12 months, without antiarrhythmic drugs. CONCLUSION: Multiple radiofrequency pulses applied inside the pulmonary veins ostia can induce severe pulmonary venous stenosis and veno-occlusive pulmonary syndrome.

Nonsurgical transthoracic epicardial catheter ablation to treat recurrent ventricular tachycardia occurring late after myocardial infarction.

OBJECTIVES: We sought to evaluate feasibility, safety and results of transthoracic epicardial catheter ablation in patients with ventricular tachycardia occurring late after an inferior wall myocardial infarction. BACKGROUND: Transthoracic epicardial catheter ablation effectively controls recurrent ventricular tachycardia (VT) in patients with Chagas' disease in whom epicardial circuits predominate. Epicardial circuits also occur in postinfarction VT. METHODS: Fourteen consecutive patients aged 53.6 +/- 14.5 years with postinfarction VT related to the inferior wall were studied. The VT cycle length was 412 +/- 51 ms. Two patients had previously undergone unsuccessful standard endocardial radiofrequency energy (RF) ablation. The VT was incessant in one patient. Left ventricular angiography showed inferior akinesia in 13 patients and an inferior aneurysm in 1 patient. Ablation was performed with a regular steerable catheter placed into the pericardial sac by pericardial puncture. RESULTS: The pericardial space was reached in all patients. Electrophysiologic evidence of an epicardial circuit was present in 7 of 30 VTs. Due to a high stimulation threshold, empirical thermal mapping was the only criterion used to select the site for ablation. Three VTs were interrupted during the first RF pulse. Two pulses were necessary to render it noninducible in 3 patients (1 VT per patient). In the remaining 4 VTs, 3, 3, 4 and 5 RF pulses, respectively, were used. The overall success was 37.14% (95% confidence interval, 11.83% to 62.45%). Patients are asymptomatic for 14 +/- 2 months. CONCLUSIONS: Postinfarction pericardial adherence does not preclude epicardial mapping and ablation to control VT related to an epicardial circuit in postinferior wall myocardial infarction.

Nonsurgical transthoracic mapping and ablation in a child with incessant ventricular tachycardia.

We report the case of an 11-month-old child with incessant ventricular tachycardia who underwent two unsuccessful endocardial ablations with standard catheters and in whom the ventricular tachycardia was interrupted only during transthoracic epicardial catheter ablation. This report outlines the usefulness and safety of this novel approach in pediatric patients before surgery when endocardial ablation fails.

Probability of occurrence of life-threatening ventricular arrhythmias in Chagas' disease versus non-Chagas' disease.

The implantable cardioverter defibrillator (ICD) is highly effective in the treatment of ventricular arrhythmias (VA) responsible for sudden cardiac death. However, the probability of occurrence of these arrhythmic events in presence of cardiomyopathy remains uncertain. The aim of this study was to compare the probability of nonoccurrence of life-threatening VA in ICD recipients with Chagas' versus non-Chagas' heart disease. Over a mean follow-up of 10.5 months, 53 ICD recipients (mean age = 50.1 years, 48 male) were evaluated. Eleven patients had Chagas' heart disease, 19 had idiopathic dilated cardiomyopathy and 23 had ischemic cardiomyopathy. Ventricular tachyarrhythmias with a cycle length < 315 ms were considered life-threatening. The cumulative probability of nonoccurrence of life-threatening VA was examined by Kaplan-Meyer method and the outcomes were submitted to the log rank test. At 2 years, the cumulative probability of life-threatening VA nonoccurrence was 0 in the Chagas' heart disease group versus 40% up to 55 months of follow-up in the non-Chagas' disease group (P = 0.0097). Among patients with cardiomyopathies of different etiologies, those with Chagas' heart disease had the lowest cumulative probability of nonoccurrence of life-threatening VA, confirming its unfavorable prognosis and the importance of preventive measures against sudden death in this disease.

Radiofrequency catheter ablation of ventricular tachycardia guided by nonsurgical epicardial mapping in chronic Chagasic heart disease.

We report a case of a 63-year-old women with Chagas' disease and recurrent, syncopal VT treated by RF catheter ablation in whom endocardial application of RF energy was guided by nonsurgical epicardial mapping. The procedure was undertaken in the electrophysiology laboratory under deep anesthesia. VT was interrupted after 2.4 seconds of application and rendered noninducible afterwards. Two weeks after the procedure, a distinct morphology VT was induced by programmed ventricular stimulation, and the patient was started on amiodarone, remaining asymptomatic 12 months after the procedure.

Long-term results of visually guided left ventricular reconstruction as single therapy to treat ventricular tachycardia associated with postinfarction anteroseptal aneurysm.

INTRODUCTION: Postinfarction ventricular tachycardia (VT), anteroseptal aneurysm, and ventricular dysfunction are commonly associated and predict a poor long-term prognosis. Surgical left ventricular reconstruction, which includes double plication of the anterior and septal wall, can improve ventricular function. This article analyzes the long-term efficacy of such a procedure to control recurrence of VT in a group of 50 consecutive patients. METHODS AND RESULTS: The study group consisted of 50 consecutive patients operated on between December 1986 and December 1994. The group comprised 44 men and 6 women. The mean age was 56+/-11 years. All patients had spontaneous VT following an anterior myocardial infarction. Twenty-five patients had two or more episodes of VT (eight presented as cardiac arrest, nine as syncope). Coronary artery disease was limited to the left anterior descending artery in 27 patients. An anteroseptal aneurysm was present in 49 patients. All patients had VT induced by programmed ventricular stimulation before surgery, and left ventricular reconstruction was performed without intraoperative mapping in all cases. Total mortality, VT recurrence, and sudden death rate were the endpoints of the study. In-hospital mortality was 8%. Postoperative left ventricular ejection fraction improved from 0.38 to 0.50 (P<0.05). Only two patients had postoperative inducible VT. Overall survival, VT recurrence rate, and sudden death rate were 73%, 12%, and 10%, respectively, after a median follow-up period of 6.25 years (0 to 8 years). CONCLUSION: Visually guided left ventricular reconstruction with septal and anterior wall plicature can be utilized effectively to treat recurrent VT associated with postinfarction anteroseptal aneurysm.

[Relationship between conduction persistence through the slow pathway after atrioventricular nodal reentry tachycardia radiofrequency ablation and its recurrence]. / Relação entre a persistência da condução pela via lenta nodal após ablação de taquicardia por reentrada nodal e a recorrência clínica.

PURPOSE: The aim of this study is to verify whether the persistence of conduction over the slow pathway is related to an increased trend for recurrence. METHODS: Recurrence rate was retrospectively analyzed in 126 patients who underwent slow pathway radiofrequency (RF) catheter ablation during a follow-up of 20 +/- 12 months. The ablative procedure was interrupted when AVNRT was no longer induced by atrial stimulation after intravenous infusion of isoproterenol. Ninety-eight patients had no evidence of slow pathway whereas 28 patients persisted with AV node jump and atrial echo beat. RESULTS: There were 15 recurrences: 9% of those who had no evidence of slow pathway (9 of 98 patients) and 21% of those with AV node jump and/or atrial echo beat but this difference was not statistically significant. CONCLUSION: As long as AVNRT cannot be induced by atrial pacing and isoproterenol infusion after slow pathway RF catheter ablation, the presence of AV node jump and/or atrial echo beat does not increase the risk of recurrence of AVNRT.

Endocardial and epicardial ablation guided by nonsurgical transthoracic epicardial mapping to treat recurrent ventricular tachycardia.

INTRODUCTION: An epicardial site of origin of ventricular tachycardia (VT) may explain unsuccessful endocardial radiofrequency (RF) catheter ablation. A new technique to map the epicardial surface of the heart through pericardial puncture was presented recently and opened the possibility of using epicardial mapping to guide endocardial ablation or epicardial catheter ablation. We report the efficacy and safety of these two approaches to treat 10 consecutive patients with VT and Chagas' disease. METHODS AND RESULTS: Epicardial mapping was carried out with a regular steerable catheter introduced into the pericardial space. An epicardial circuit was found in 14 of 18 mapable VTs induced in 10 patients. Epicardial mapping was used to guide endocardial ablation in 4 patients and epicardial ablation in 6. The epicardial earliest activation site occurred 107+/-60 msec earlier than the onset of the QRS complex. At the epicardial site used to guide endocardial ablation, earliest activation occurred 75+/-55 msec before the QRS complex. Epicardial mid-diastolic potentials and/or continuous electrical activity were seen in 7 patients. After 4.8+/-2.9 seconds of epicardial RF applications, VT was rendered noninducible. Hemopericardium requiring drainage occurred in 1 patient; 3 others developed pericardial friction without hemopericardium. Patients remain asymptomatic 5 to 9 months after the procedure. Interruption during endocardial pulses occurred after 20.2+/-14 seconds (P = 0.004), but VT was always reinducible and the patients experienced a poor outcome. CONCLUSION: Epicardial mapping does not enhance the effectiveness of endocardial pulses of RF. Epicardial applications of RF energy can safely and effectively treat patients with VT and Chagas' disease.

Reduction of radiation exposure time during catheter ablation with the use of pulsed fluoroscopy.

UNLABELLED: Prolonged exposure to radiation during radiofrequency catheter ablation implies a potential risk of radiodermatitis, neoplasm and genetic defects to the patient and to the operator-physician. The use of pulsed fluoroscopy is thought to reduce such a risk because the radiation dose decreases for the same period of time. The aim of the present study was to compare the radiation exposure time during pulse and continuous radiofrequency catheter ablation. METHODS: Procedures were divided according to the sort of fluoroscopy utilized and the last four cases of atrioventricular (AV) junction ablation, four of atrial flutter, five of atrial tachycardia, 16 of AV node reentrant tachycardia, 16 of AV tachycardia and 10 of ventricular tachycardia in which pulsed and continuous fluoroscopy were utilized were respectively separated into Group I (pulse fluoroscopy) and Group II (continuous fluoroscopy) with 55 patients in each group. Fluoroscopy was generated by the same device in the two groups. Continuous fluoroscopy used 2 mA and automatic kV adjustment (automatic brightness stabilizer) ranging from 70 to 110 kV. Pulsed fluoroscopy was set at 7 squares/s with 25 mA and automatic kV adjustment. Fluoroscopy time was registered by the fluoroscopy device counter. RESULTS: Procedure duration, success rate and complications did not differ between Groups I and II. Fluoroscopy time, however, was 4.4+/-4 min during pulsed fluoroscopy and 27+/-23 min during continuous fluoroscopy (p=0.001). CONCLUSION: During radiofrequency catheter ablation procedures, the use of pulsed fluoroscopy set at 7 squares/s, decreases the radiation exposure time by 80% as compared to continuous fluoroscopy without changing procedure duration and success rate.

Síncope / Syncope

Síncope é um evento clínico bastante comum, de difícil diagnóstico, muitas vezes incapacitante e, em diversas situaçöes, de mau prognóstico. Muitas são as possíveis etiologias e o principal papel do médico é distinguir causas benignas daquelas de mau prognóstico. Na maioria das vezes, muitos testes dispendiosos têm sido realizados, sem que se atinja o sucesso esperado. O objetivo deste artigo será determinar os principais mecanismos fisiopatológicos da síncope e qual a melhor estratégia para que se determine a etiologia e, portanto, a terapêutica ideal.