Ricardo Ruiz-Granell

Diagnosis, management, and outcomes of patients with syncope and bundle branch block

Aims Although patients with syncope and bundle branch block (BBB) are at high risk of developing atrio-ventricular block, syncope may be due to other aetiologies. We performed a prospective, observational study of the clinical outcomes of patients with syncope and BBB following a systematic diagnostic approach. Methods and results Patients with ≥1 syncope in the last 6 months, with QRS duration ≥120 ms, were prospectively studied following a three-phase diagnostic strategy: Phase I, initial evaluation; Phase II, electrophysiological study (EPS); and Phase III, insertion of an implantable loop recorder (ILR). Overall, 323 patients (left ventricular ejection fraction 56 ± 12%) were studied. The aetiological diagnosis was established in 267 (82.7%) patients (102 at initial evaluation, 113 upon EPS, and 52 upon ILR) with the following aetiologies: bradyarrhythmia (202), carotid sinus syndrome (20), ventricular tachycardia (18), neurally mediated (9), orthostatic hypotension (4), drug-induced (3), secondary to cardiopulmonary disease (2), supraventricular tachycardia (1), bradycardia–tachycardia (1), and non-arrhythmic (7). A pacemaker was implanted in 220 (68.1%), an implantable cardioverter defibrillator in 19 (5.8%), and radiofrequency catheter ablation was performed in 3 patients. Twenty patients (6%) had died at an average follow-up of 19.2 ± 8.2 months. Conclusion In patients with syncope, BBB, and mean left ventricular ejection fraction of 56 ± 12%, a systematic diagnostic approach achieves a high rate of aetiological diagnosis and allows to select specific treatment.

Ablation or conservative management of electrical storm due to monomorphic ventricular tachycardia: differences in outcome

AIMS Electrical storm (ES) is a life-threatening condition that predicts bad prognosis. Treatment includes antiarrhythmic drugs (AAD) and catheter ablation (CA). The present study aims to retrospectively compare prognosis in terms of survival and ES recurrence in 52 consecutive patients experiencing a first ES episode. METHODS AND RESULTS Patients were admitted from 1995 to 2011 and treated for ES by conservative therapy (pharmacological, 29 patients) or by CA (23 patients), according to the physicians preference and time of occurrence, i.e. conservative treatments were more frequently administered during the first years of the study, as catheter ablation became more frequent as the years passed by. After a median follow-up of 28 months, no differences either in survival (32% vs. 29% P = 0.8) or in ES recurrence (38% in ablated vs. 57% in non-ablated patients, P = 0.29) were observed between groups. Low left ventricle ejection fraction (LVEF) was the only variable associated with ES recurrence in ablated patients. When including patients with LVEF > 25%, ES recurrence was significantly lower in ablated patients (24 months estimated risk of ES recurrence was 21% vs. 62% in ablated and non-ablated patients, respectively); however, no benefit in survival was observed. CONCLUSION Our data suggest that in most patients, especially those with an LVEF > 25%, catheter ablation following a first ES episode, decreases the risk of ES recurrence, without increasing survival.

Value of Early Cardiovascular Magnetic Resonance for the Prediction of Adverse Arrhythmic Cardiac Events After a First Noncomplicated ST-Segment-Elevation Myocardial Infarction

Background— Infarct size (IS) determined by cardiac magnetic resonance (CMR) has proven an additional value, on top of left ventricular ejection fraction (LVEF), in prediction of adverse arrhythmic cardiac events (AACEs) in chronic ischemic heart disease. Its value soon after an acute ST-segment–elevation myocardial infarction remains unknown. Our aim was to determine whether early CMR can improve AACE risk prediction after acute ST-segment–elevation myocardial infarction. Methods and Results— Patients admitted for a first noncomplicated ST-segment–elevation myocardial infarction were prospectively followed up. A total of 440 patients were included. All of them underwent CMR 1 week after admission. CMR-derived LVEF and IS (grams per meter squared) were quantified. AACEs included postdischarge sudden death, sustained ventricular tachycardia, and ventricular fibrillation either documented on ECG or recorded via an implantable cardioverter-defibrillator. Within a median follow-up of 2 years, 11 AACEs (2.5%) were detected: 5 sudden deaths (1.1%) and 6 spontaneous ventricular tachycardia/ventricular fibrillation. In the whole group, AACEs associated with more depressed LVEF (adjusted hazard ratio [95% confidence interval], 0.90 [0.83–0.97]; P<0.01) and larger IS (adjusted hazard ratio [95% confidence interval], 1.06 [1.01–1.12]; P=0.01). According to the corresponding area under the receiver operating characteristic curve, LVEF ⩽36% and IS ≥23.5 g/m2 best predicted AACEs. The vast majority of AACEs (10/11) occurred in patients with simultaneous depressed LVEF ⩽36% and IS ≥23.5 g/m2 (n=39). Conclusions— In the era of reperfusion therapies, occurrence of AACEs in patients with an in-hospital noncomplicated first ST-segment–elevation myocardial infarction is low. In this setting, assessment of an early CMR-derived IS could be useful for further optimization of AACE risk prediction.

Impact of anti-tachycardia pacing on atrial fibrillation burden when added on top of preventive pacing algorithms: results of the prevention or termination (POT) trial

AIMS The efficacy of preventive pacing algorithms (PPA) and anti-tachycardia pacing (ATP) in reducing atrial fibrillation (AF) burden remains controversial. The aim of this study was to assess whether ATP on top of PPA decreases AF burden. METHODS AND RESULTS A series of 199 consecutive patients, with conventional indications for pacing, and documented AF, received a DDDR (rate adaptive dual chamber pacemaker) pacemaker with ATP capabilities (AT 500 Medtronic). After 3 months of conventional DDDR pacing at 70 b.p.m., AF burden was analysed. If patients had >30 min/week of AF, they were randomized to PPA or to PPA+ATP for 3 months (period 1). They were then crossed to the alternative therapy (period 2) and followed three additional months with a 1-month wash out period in-between. A group of 85 patients were randomized. Mean age 68 +/- 8 years, 61% men. Both groups showed a significant decrease in AF burden at the end of period 1 (64 and 81%, respectively). CONCLUSIONS Atrial pacing with PPA decreases AF burden in patients with pacing indication. We did not observe a further decrease in AF burden or in the number of episodes when adding ATP on top of PPA.

Endo-Epicardial Versus Only-Endocardial Ablation as a First Line Strategy for the Treatment of Ventricular Tachycardia in Patients With Ischemic Heart Disease

Background—Epicardial ablation has shown improvement in clinical outcomes of patients with ischemic heart disease (IHD) after ventricular tachycardia (VT) ablation. However, usually epicardial access is only performed when endocardial ablation has failed. Our aim was to compare the efficacy of endocardial+epicardial ablation versus only endocardial ablation in the first procedure in patients with IHD. Methods and Results—Fifty-three patients with IHD, referred for a first VT ablation to our institution, from 2012 to 2014, were included. They were divided in 2 groups according to enrollment time: from May 2013, we started to systematically perform endo-epicardial access (Epi-Group) as first-line approach in consecutive patients with IHD (n=15). Patients who underwent only an endocardial VT ablation in their first procedure (Endo-Group) included patients with previous cardiac surgery and the historical (before May 2013; n=35). All late-potentials in the scar zone were eliminated, and if VT was tolerated, critical isthmuses were also approached. The end point was the noninducibility of any VT. During a median follow-up of 15±10 months, the combined end point (hospital or emergency admission because of a ventricular tachycardia or reablation) occurred in 14 patients of the Endo-group and in one patient in the Epi-group (event-free survival curves by Grey-test, P=0.03). Ventricular arrhythmia recurrences occurred in 16 and in 3 patients in the Endo and Epi-Group, respectively (Grey-test, P=0.2). Conclusions—A combined endocardial–epicardial ablation approach for initial VT ablation was associated with fewer readmissions for VT and repeat ablations. Further studies are warranted.

Implantation of single-lead atrioventricular permanent pacemakers guided by electroanatomic navigation without the use of fluoroscopy

AIMS Fluoroscopy is the standard and almost unique tool used for cardiac imaging during permanent pacemaker implantation, and its use implies exposure of patients and operators to radiation. The usefulness for this purpose of electroanatomic systems not based on fluoroscopy is unknown. Our aim was to study the feasibility of implanting single-lead VDD pacemakers without the use of fluoroscopy. METHODS AND RESULTS EnSite NavX, a catheter navigation tool based on the creation of a voltage gradient across the thorax of the patient, was used as an exclusive imaging tool during the implantation of single-lead atrioventricular (VDD) permanent pacemakers in 15 consecutive patients with atrioventricular block and normal sinus node function. A retrospective series of 15 consecutive patients in whom VDD pacemakers were implanted under fluoroscopic guidance was used as a control group. The pacemaker could be implanted in all patients. Time spent to obtain the right ventricle anatomy was 10.1 +/- 5.4 min and time to place the lead in an adequate position was 10.1 +/- 7.8 min. Total implant time was 59.3 +/- 15.6 min (51.5 +/- 12.3 min in the control group; P = 0.14). In one patient, a short pulse of radioscopy was needed for a correct catheterization of the subclavian vein. No complications were observed during the procedure. One lead dislodgement that required re-operation was detected 24 h after implantation. At 3 months follow-up, all pacemakers were functioning properly, with adequate pacing and sensing thresholds. CONCLUSION Electroanatomic navigation systems such as NavX can be used for cardiac imaging during single-lead atrioventricular pacemaker implantation as a reliable and safe alternative to fluoroscopy.

Síncope y bloqueo de rama. Rendimiento del uso escalonado del estudio electrofisiológico y de la monitorización electrocardiográfica prolongada

INTRODUCTION AND OBJECTIVES The objective of this study was to determine the diagnostic yield of a stepped protocol involving an electrophysiologic study (EPS) and implantable loop recorders (ILR) in patients with syncope and bundle branch block (BBB). METHODS Eighty-five consecutive patients referred for syncope and BBB after initial non-diagnostic assessment underwent EPS including a pharmacological challenge with procainamide. Those patients without indication for defibrillator implantation received ILRs. Follow-up continued until diagnosis or end of battery life. RESULTS The EPS was diagnostic in 36 patients (42%). The most frequent diagnoses were paroxysmal atrioventricular block (AVB) (n=27), followed by ventricular tachycardia (VT) (n=6). All patients with VT had structural heart disease; left BBB was more prevalent in this group. Thirty-eight patients received ILRs and diagnosis was achieved in 13 (34%) of them; paroxysmal AVB (n=10) was the most frequent diagnosis. Median follow-up to diagnosis of paroxysmal AVB was 97 days (interquartile range 60-117 days). Paroxysmal AVB was more frequent in patients with right BBB and prolonged PR interval and/or axis deviation. We found no occurrence of VT or arrhythmic death during follow-up. CONCLUSIONS The most common etiology of syncope in patients with BBB was paroxysmal AVB, followed by VT. The stepped use of EPS and ILR in negative patients enables us to safely achieve a high diagnostic yield, given that VT is usually diagnosed during EPS.

Consenso sobre la terapia de Resincronización Cardíaca

Dentro del arsenal terapeutico de la insuficiencia cardiaca, la resincronizacion cardiaca cada vez esta adquiriendo un papel mas importante como coadyuvante del tratamiento medico. Se ha demostrado ampliamente que en los pacientes con insuficiencia cardiaca avanzada y bloqueo de rama izquierda, la estimulacion biventricular produce una mejoria hemodinamica y clinica, asi como un remodelado inverso del ventriculo izquierdo. Algunos estudios sugieren tambien una disminucion de la mortalidad. Sin embargo, es una terapia costosa y compleja que no esta libre de complicaciones y con un porcentaje de pacientes que no mejoran. Por ello, para su correcta aplicacion es necesaria una colaboracion multidisciplinaria. El Grupo de Trabajo de Resincronizacion Cardiaca de la Sociedad Espanola de Cardiologia ha redactado el presente documento de consenso con especial interes por exponer las indicaciones de esta terapia, asi como la correcta seleccion de los dispositivos y su adecuada tecnica de implante y seguimiento.

Comments on the 2016 ESC Guidelines for the Management of Atrial Fibrillation.

In line with the methodology recommended by the Guidelines Committee of the Spanish Society of Cardiology,1 the present article discusses the innovations and most controversial aspects of the recent guidelines for atrial fibrillation (AF).2 Notably, of 154 recommendations, only 23 (15%) have a level of evidence A and 80 (52%) a level of evidence B, confirming the need for further clinical research into this condition. Some of the most novel or relevant aspects of the guidelines are summarized in Table, in conjunction with some critical comments.

Time-to-Effect–Based Dosing Strategy for Cryoballoon Ablation in Patients With Paroxysmal Atrial Fibrillation: Results of the plusONE Multicenter Randomized Controlled Noninferiority Trial

Background The optimal dosage of cryotherapy during cryoballoon ablation of pulmonary veins is still unclear. This trial tested the noninferiority of a novel, individualized, cryotherapy-dosing strategy for each vein. Methods and Results This prospective, randomized, multicenter, noninferiority study included 140 patients with paroxysmal atrial fibrillation, which was refractory to antiarrhythmic drugs. Patients were randomly assigned to a conventional strategy of 180-second cryoballoon applications per vein with a bonus freeze (control group, n=70) or to a shorter-time application protocol, with 1 application that lasted the time required for electric block time to effect plus 60- and a 120-second freeze bonus (study group, n=70). Patients were followed with a long-term monitoring system of 30 days. At 1-year follow-up, no difference was observed in terms of free atrial fibrillation-recurrence rates: 79.4% in control versus 78.3% in study group (&Dgr;=1.15%; 90% confidence interval, −10.33% to 12.63%; P=0.869). Time to effect was detected in 72.1% of veins. The control and study groups had similar mean number of applications per patient (9.6±2 versus 9.9±2.4; P=0.76). Compared with controls, the study group had a significantly shorter cryotherapy time (28.3±7 versus 19.4±4.3 minutes; P<0.001), left atrium time (104±25 versus 92±23 minutes; P<0.01), and total procedure time (135±35 versus 119±31 minutes; P<0.01). No differences were observed in complications or acute reconnections. Conclusions The new time-to-effect–based cryotherapy dosage protocol led to shorter cryotherapy and procedure times, with equal safety, and similar acute and 1-year follow-up results, compared with the conventional approach. Clinical Trial Registration URL: https://clinicaltrials.gov. Unique identifier: NCT02789358.