Primary prevention implantable cardioverter-defibrillator and cardiac resynchronization therapy-defibrillator in elderly patients: results of a Spanish multicentre study.

AIMS: Currently, there continues to be a lack of evidence regarding outcomes associated with device-based therapy for ventricular arrhythmias in elderly patients, even more in primary-prevention indications. We aimed to describe the follow-up in terms of efficacy and safety of implantable cardioverter-defibrillator (ICD) therapy in a large cohort of elderly patients. METHODS AND RESULTS: Retrospective multicentre study performed in 15 Spanish hospitals. Consecutive patients referred for ICD implantation before 2011 were included. One hundred and sixty-two of 1174 patients (13.8%) ≥75 years were considered as 'elderly'. When compared with those patients <75, this subgroup presented more co-morbid conditions, including hypertension, chronic obstructive pulmonary disease , and renal failure, and more previous hospitalizations due to heart failure (HF). During a mean follow-up of 104.4 ± 3.3 months, 162 patients (14%) died, 120 in the younger age (12.4%), and 42 (24.4%) in the elderly. Kaplan-Meier analysis showed an increased probability of death with increasing age (17, 24, 28, and 69% at 12, 24, 48, and 60 months of follow-up in the elderly group). There was neither difference regarding the rate of appropriate nor inappropriate ICD intervention. CONCLUSION: In a real-world scenario, elderly patients comprise ∼15% of ICD implantations for primary prevention of sudden cardiac death (SCD). Although the rate of appropriate therapy is similar between groups, the benefit of ICD is attenuated for a major increase in mortality risk among those patients ≥75 years at the moment of device implantation.

Implantable loop recorder allows an etiologic diagnosis in one-third of patients. Results of the Spanish reveal registry.

BACKGROUND: The implantable loop recorder (ILR) is a useful tool for diagnosing paroxysmal conditions potentially related to arrhythmias. Most investigations have focused on selected clinical studies or high-volume centers. The aim of this study was to evaluate the indications and outcomes of the ILR in real clinical practice. METHODS AND RESULTS: This was a prospective, multicenter registry of patients undergoing ILR implantation for clinical indications (April 2006-December 2008). Clinical characteristics (symptoms, arrhythmias, treatments) were recorded in a database. Follow-up data at 1 year or after the occurrence of the first episode were also recorded. Total enrollment: 743 patients (male, 413, 55.6%; 64.9 ± 16 years); 228 (30.7%) had structural heart disease (SHD), and 183 (24.6%), bundle branch block (BBB). Recurrent syncope (76.4%) was the most common indication for implantation. Complete follow-up was obtained for 680 patients (91.5%). Three hundred and twenty-five patients (48%) presented 414 events, with a final diagnosis in 230 patients (70.8% of patients with events; 33.1% of patients with follow-up). Syncope secondary to bradyarrhythmia was the most frequent diagnosis. Similar rates of final diagnoses were noted in subgroups of SHD, BBB and normal heart. Regarding the cause of implantation, higher event rates were registered among patients with recurrent syncope. CONCLUSIONS: One-third of patients obtained a final diagnosis with the ILR, independent of the baseline characteristics. Only the cause of implantation provided different rates of final diagnosis.

Dronedarone for recurrent ventricular tachycardia: a real alternative?

Sustained ventricular tachycardia (VT) is an important cause of morbidity and sudden death in patients with dilated cardiomyopathy. Although ICD effectively terminate VT episodes and improve survival, shocks reduce quality of life, and episodes of VT predict increased risk of heart failure and death despite effective therapy. Patients suffering recurrent VT episodes remain a challenge. Antiarrhytmic therapy reduces VT episodes, but it is associated with serious adverse events, and disappointing efficacy. Catheter ablation has emerged as an important option to control recurrent VT, but major procedure-related complications, and even death, are still issues to concern. And even with these armamentaria, some patients still have recurrent VT episodes and ICD shocks. We report on a patient with non-ischemic dilated cardiomyopathy and recurrent ventricular tachycardia resistant to multiple antiarrhytmic agents, in whom dronedarone was effective in completely suppressing ventricular tachycardia episodes.

Stroke and Systemic Embolism After Successful Ablation of Typical Atrial Flutter.

BACKGROUND: Following successful cavotricuspid isthmus (CTI) ablation during typical atrial flutter (AFL), anticoagulation therapy is usually withdrawn. However, potential subsequent atrial fibrillation (AF) in these patients may increase embolic risk in the long term. Embolic rates in this setting have not been clearly established. Our aim was to determine the incidence of stroke/systemic embolism following radiofrequency ablation of AFL, particularly in those without a prior history of AF. HYPOTHESIS: After succesful AFL ablation, patients may suffer embolic complications in the long-term follow-up, mainly due to asymptomatic AF episodes. METHODS: We conducted a retrospective analysis of all patients who underwent CTI ablation due to AFL in our center between 2006 and 2009. RESULTS: During the study period, 188 patients (mean age, 62.9 ± 8.6 years) underwent CTI ablation; 120 without prior AF were included in the study. At the end of the follow-up period (mean, 5.0 ± 2.4 years), 56.7% of patients (68/120) remained in sinus rhythm, 7/120 experienced a recurrence of AFL, and 45/120 (38%) developed AF. Ischemic stroke occurred in 11 patients and systemic embolism in 1. Of these patients, 5 had documented AF following AFL ablation. In the remaining 7 cases, previously undiagnosed AF was subsequently diagnosed at the time of stroke/embolism. CONCLUSIONS: Patients with AFL who undergo successful ablation are by no means free from embolic complications during long-term follow-up, mainly due to a high rate of AF development. Given the difficulties in detecting AF and the uncertainty about the temporal relation of AF and stroke, oral anticoagulation may need to be continued in those patients with underlying stroke risk factors.

Initial experience and treatment of atrial fibrillation using a novel irrigated multielectrode catheter: Results from a prospective two-center study.

BACKGROUND: PV electrical isolation has become the cornerstone of catheter ablation for the treatment of atrial fibrillation (AF). Several strategies have been proposed to achieve this goal. The aim of this study was to assess the efficacy and safety of AF ablation using a new circular irrigated multielectrode ablation catheter designed to achieve single-delivery pulmonary vein (PV) isolation. METHODS: Thirty-five patients with drug refractory paroxysmal AF and normal ejection fraction from two centers were prospectively enrolled in this study. All patients underwent PV isolation with an nMARQ circular irrigated multielectrode ablation catheter guided by an electroanatomic mapping system. Magnetic resonance imaging was performed to exclude PV stenosis. RESULTS: PV isolation was achieved in 138 of 140 (98.57%) targeted veins. The mean procedure time was 79.5 min (SD 39.3 min). During a mean follow up of 16.8±2.8 months, 27 of 35 (77.2%) patients were free of AF. No PV narrowing was observed. One case of pericardial effusion due to perforation of the left atrial free wall during catheter manipulation did occur. CONCLUSIONS: PV isolation with a circular irrigated multielectrode ablation catheter is a feasible technique with a high acute success rate. The majority of patients remained asymptomatic during the midterm follow-up period. PV stenosis was not detected. While only a single serious adverse event occurred, this technique׳s safety profile should be tested in larger studies.

Differences in the yield of the implantable loop recorder between secondary and tertiary centers.

BACKGROUND: The implantable loop recorder (ILR) is a useful tool for diagnosis of syncope or palpitations. Its easy use and safety have extended its use to secondary hospitals (those without an Electrophysiology Lab). The aim of the study was to compare results between secondary and tertiary hospitals. METHODS: National prospective and multicenter registry of patients with an ILR inserted for clinical reasons. Data were collected in an online database. The follow-up ended when the first diagnostic clinical event occurred, or 1 year after implantation. Data were analyzed according to the center of reference; hospitals with Electrophysiology Lab were considered Tertiary Hospitals, while those hospitals without a lab were considered Secondary Hospitals. RESULTS: Seven hundred and forty-three patients (413 [55.6%] men; 65 ± 16 year-old): 655 (88.2%) from Tertiary Centers (TC) and 88 (11.8%) from Secondary Centers (SC). No differences in clinical characteristics between both groups were found. The electrophysiologic study and the tilt table test were conducted more frequently in Tertiary Centers. Follow-up was conducted for 680 (91.5%) patients: 91% in TC and 94% in SC. There was a higher rate of final diagnosis among SC patients (55.4% vs. 30.8%; p < 0.001). Tertiary Hospital patients showed a trend towards a higher rate of neurally mediated events (20% vs. 4%), while bradyarrhythmias were more frequent in SC (74% vs. 60%; p = 0.055). The rate of deaths and adverse events was similar in both populations. CONCLUSIONS: Patients with an ILR in SC and TC have differences in terms of the use of complementary tests, but not in clinical characteristics. There was a higher rate of diagnosis in Secondary Hospital patients.

[Sirolimus-eluting stents to treat lesions with a high risk of restenosis. Six-month clinical follow-up in the first 100 patients]. / Stent liberador de rapamicina en el tratamiento de lesiones coronarias con alto riesgo de reestenosis. Seguimiento clínico a 6 meses de los primeros 100 pacientes.

INTRODUCTION: Sirolimus-eluting stents have been shown to be effective in de-novo coronary lesions, reducing restenosis strikingly in a subset of lesions with a low or moderate risk of restenosis. We decided to assess their usefulness in lesions with a high risk of restenosis. PATIENTS AND METHOD: We included consecutive patients with lesions that met at least one of the following criteria: a) in-stent restenosis; b) diffuse lesion (>20 mm); c) small vessel (< or =2.5 mm), and d) total occlusion. RESULTS: Between June 2002 to December 2002, 100 patients were included (61 [11] years, 84% men, 21% with diabetes). In all, 154 lesions were treated (34% diffuse lesions, 36% in small vessels, 20% in-stent restenosis and 20% occlusions). An average of 1.6 (0.7) stents were implanted per patient. Mean diameter was 2.74 (0.26) mm, mean length was 21 (8.5) mm and total stent length per patient was 33 (16) mm. The acute success rate was 98%. After the procedure 2 (2%) non-Q-wave infarctions were diagnosed. No episodes of acute or subacute thrombosis occurred. During a follow-up period of 8.5 (2) months (range 6-12 months) there were two (2%) late thromboses, one of which caused an infarction. Target lesion revascularization was required in 3 patients (3%), two of whom were the patients with late thrombosis. CONCLUSIONS: Sirolimus-eluting stents can be used in lesions with a high risk of restenosis. The rate of thrombosis was low, and the use of these stents was associated with a strikingly low rate of target lesion revascularization during follow-up.

[Importance of severe lesions left untreated in patients with acute coronary syndromes and angioplasty of the culprit lesion]. / Importancia de las lesiones severas no tratadas en pacientes con síndrome coronario agudo y angioplastia de la lesión causante.

INTRODUCTION AND OBJECTIVES: Patients with acute coronary syndromes may have significantly stenotic nonculprit lesions that do not show complex lesion morphology. We investigated whether these lesions were prone to become unstable since they exist within a prothrombotic and inflammatory systemic milieu. PATIENTS AND METHOD: We evaluated the clinical course of 150 patients after successful angioplasty of a culprit lesion: 75 patients with a severely stenotic but uncomplicated nonculprit lesion (group A) and 75 patients without these lesions (group B). RESULTS: In group A, 1 patient (1.3%) required angioplasty of an initially nonculprit lesion, and in group B, 2 patients (2.6%) died in cardiogenic shock. After 1 year of follow-up, in group A, 4 patients (5.3%) died (cardiac deaths), 1 patient (1.3%) had a myocardial infarction, and 10 patients (13.3%) underwent a repeat revascularization procedure, which in 6 cases (8%) was angioplasty of an initially nonculprit lesion. In all 6 patients with angioplasty of the initially nonculprit lesion, revascularization was done within the first 4 months and was indicated for unstable angina. In group B, 1 patient (1.3%) died (noncardiac death) and 2 patients (2.6%) underwent a repeat revascularization procedure because of restenosis. Survival curves were significantly different between both groups. Belonging to group A was the only independent predictor for events, and within this group location of the lesion in the left anterior descending artery was the main predictor. CONCLUSIONS: The presence of nonculprit lesions of uncomplicated morphology at the time of a percutaneous revascularization procedure for a culprit lesion in patients with acute coronary syndrome is a short- and middle-term predictor of a moderate rate of recurrent events when these initially innocuous lesions become unstable.

Cryoablation versus radiofrequency ablation for the treatment of atrioventricular nodal reentrant tachycardia: results of a prospective randomized study.

PURPOSE: Radiofrequency ablation (RF) of atrioventricular reentrant tachycardia (AVNRT) is an effective method for treating this arrhythmia. However, inadverted AV block requiring implantation of permanent pacemaker is a worrisome side effect. Although permanent AV block seems to be rare nowadays, patients are by no means spared from this severe complication. Catheter cryoablation is emerging as an alternative technology with an excellent safety profile, but limited data exist regarding its efficacy. METHODS: We conducted a randomized study among patients with AVNRT remitted to our center for EP study and ablation between January 2008 and June 2010. After giving a written consent, patients were randomized to conventional RF or cryoablation, unless specific preference of patient was stated. Primary outcomes were acute success, SVT recurrence, and complications, including AV block. RESULTS: One hundred nineteen patients were included (60 cryoablation and 59 conventional RF). There were no differences in demographic and clinical baseline data between groups. Acute procedural success was achieved in 59 patients (98 %) in cryoablation group and 59 (100 %) in RF. One patient in RF group underwent complete AV block and pacemaker implantation. Over a mean follow-up period of 256.6 days, there was a significant difference in AVNRT recurrence between cryoablation and RF patients (15 versus 3.4 %, p = 0.03). CONCLUSION: Catheter cryoablation of AVNRT is a clinically effective alternative to RF ablation, with excellent acute success rate. Despite a slightly higher rate of recurrence during long-term follow-up, these results suggest that cryoablation may be considered as first-line approach, especially in younger people, where the risk of permanent pacing because of inadvertent AV block may be relevant.

Prevención primaria con cardiodesfibrilador implantable y terapia de resincronización cardíaca en pacientes ancianos: resultados de un estudio multicéntrico español

Propósito: a la fecha sigue sin haber pruebas en cuanto a los resultados del uso de dispositivos para arritmias ventriculares en pacientes añosos, y menos aun para indicaciones de prevención primaria. La finalidad del estudio fue describir la evolución en términos de la eficacia y seguridad de la terapia con cardiodesfibriladores implantables (CDI) en una gran cohorte de pacientes añosos. Métodos y resultados: estudio multicéntrico retrospectivo realizado en 15 hospitales españoles. Se incluyeron pacientes consecutivos referidos para implante de CDI antes de 2011. Se consideró que 162 de los 1.174 pacientes (13,8%) con 75 años o más eran “añosos”. Comparado con aquellos pacientes <75 años, este subgrupo presentaba más comorbilidades como hipertensión, enfermedad pulmonar obstructiva crónica y falla renal, y más internaciones previas debido a insuficiencia cardíaca (IC). A lo largo de una media de seguimiento de 104,4 ± 3,3 meses, fallecieron 162 pacientes (14%), 120 de los más jóvenes (12,4%) y 42 (24,4%) de los añosos. El análisis de Kaplan-Meier mostró un aumento de la probabilidad de morir con el aumento de la edad (17, 24, 28, y 69% a los 12, 24, 48, y 60 meses de seguimiento en el grupo de pacientes añosos). No hubo diferencias entre la tasa de intervenciones con CDI apropiadas o inapropiadas. Conclusión: en el mundo real, los pacientes añosos constituyen ~15% de los implantes de CDI para prevención primaria de la muerte súbita cardíaca (MSC). Si bien la tasa de terapias apropiadas es similar en los diferentes grupos, el beneficio de CDI se ve atenuado por un mayor aumento del riesgo de mortalidad entre los pacientes que son mayores de 75 años al momento del implante.

[Management of syncope in the emergency department without hospital admission: usefulness of an arrhythmia unit coordinated protocol]. / Manejo del síncope en el servicio de urgencias sin ingreso hospitalario: utilidad de un protocolo coordinado con la unidad de arritmias.

INTRODUCTION AND OBJECTIVES: The main aim of this study was to demonstrate that a protocol for managing syncope in the emergency department that is based on the early detection of heart disease enables patients to be diagnosed quickly and with few admissions, without there being a negative impact on prognosis. METHODS: The study was performed prospectively in 199 consecutive patients (54% male; mean age, 67 [17] years) who presented with syncope at the emergency department of our hospital during a 17-month period. A two-step diagnostic algorithm was developed in which patients initially underwent clinical and electro-cardiographic assessment, and thereafter were submitted to a diagnostic protocol that involved carrying out a sequence of diagnostic tests in the emergency room to avoid hospital admission. RESULTS: A presumptive diagnosis was established in 120 (60%) patients during the initial assessment. After completion of the diagnostic protocol, 78% of patients were given a clear diagnosis within a mean stay of 19 [15] h in the emergency department. Some 10% of patients were admitted. Three patients died during a mean follow-up period of 237 days. CONCLUSIONS: Implementation of a protocol for managing syncope in the emergency department that was based on screening patients according to the presence of heart disease enabled a large percentage to receive a diagnosis. Moreover, the majority of patients could be discharged rapidly from the emergency department without there being any negative impact on medium-term prognosis.