José Olagüe

Comparison of Effectiveness of Right Ventricular Septal Pacing Versus Right Ventricular Apical Pacing

Chronic right ventricular apical pacing (RVAP) has been associated with negative hemodynamic and clinical effects. The aim of the present study was to compare RVAP with right ventricular septal pacing (RVSP) in terms of echocardiographic features and clinical outcomes. A total of 93 patients without structural heart disease and with an indication for a permanent pacemaker were randomly assigned to receive a screw-in lead either in the RV apex (n = 46) or in the RV mid-septum (n = 47). The patients were divided into 3 subgroups according to the percentage of ventricular pacing: control group (n = 21, percentage of ventricular pacing < or =10%), RVAP group (n = 28), or RVSP group (n = 32; both latter groups had a percentage of ventricular pacing >10%). The RVAP group had more intraventricular dyssynchrony and a trend toward a worse left ventricular ejection fraction compared to the RVSP and control groups at 12 months of follow-up (maximal delay to peak systolic velocity between any of the 6 left ventricular basal segments was 57.8 +/- 38.2, 35.5 +/- 20.6, and 36.5 +/- 17.8 ms for RVAP, RVSP, and control group, respectively; p = 0.006; mean left ventricular ejection fraction 62.9 +/- 7.9%, 66.5 +/- 7.2%, and 66.6 +/- 7.2%, respectively, p = 0.14). Up to 48.1% of the RVAP patients showed significant intraventricular dyssynchrony compared to 19.4% of the RVSP patients and 23.8% of the controls (p = 0.04). However, no overt clinical benefits from RVSP were found. In conclusion, RVAP was associated with increased dyssynchrony compared to the RVSP and control patients. RVSP could represent an alternative pacing site in selected patients to reduce the harmful effects of traditional RVAP.

Evaluation of a new standardized protocol for the perioperative management of chronically anticoagulated patients receiving implantable cardiac arrhythmia devices

BACKGROUND Perioperative management of oral anticoagulation (OAC) in patients receiving pacemakers or implantable cardioverter-defibrillators remains an issue of concern. OBJECTIVE We sought to evaluate the safety and the effect on the hospital length of stay of a new standardized protocol for perioperative management of OAC in this setting. METHODS The new standardized protocol classified patients according to a renewed evaluation of their thromboembolic (TE) risk. Briefly, patients were considered at moderate-to-high TE risk if they had a mechanical valvular prostheses irrespective of type and location or atrial fibrillation associated with a CHADS(2)score of ≥2, mitral stenosis or previous stroke, and underwent device implantation without stopping OAC (OAC continued, n = 129). Complete interruption of OAC before surgery was performed in low-TE-risk patients (OAC interrupted, n = 82). A retrospective cohort of patients managed with a classic heparin-bridging strategy served as a control group, with 62 patients considered at moderate-to-high TE risk according to previous guidelines (receiving pre- and postoperative low-molecular-weight heparin) and 146 considered at low TE risk (receiving only low doses of postoperative low-molecular-weight heparin). RESULTS TE events were comparable between the 2 strategies. Patients entering the new standardized protocol had significantly lower rates of pocket hematoma (2.3% for OAC continued vs 17.7% for moderate-to-high TE risk bridging controls, P = .0001, and 0% for OAC interrupted vs 13% for low-TE-risk bridging controls, P <.0001) and shorter hospital stays. A mean of 3.34 hospitalization days per patient were saved with the new standardized protocol, with an estimated cost savings of €850.83 per patient. CONCLUSIONS Implantation of the new standardized protocol resulted in a significant reduction in bleeding complications and hospital stays, with adequate protection against TE events and significant cost savings.

Cardiac magnetic resonance imaging at 1.5 T in patients with cardiac rhythm devices

AIMS Recent studies suggest that non-cardiac magnetic resonance imaging (MRI) scanning can be performed safely in selected cardiac rhythm device patients. However, little is known about the safety of performing specific cardiac MRI in this setting. We sought to determine the feasibility of cardiac MRI in patients with pacemakers (PMs) or implantable cardioverter-defibrillators (ICDs). METHODS AND RESULTS Thirty-eight patients underwent a total of 39 (8 ICDs and 31 PM) cardiac MRI examinations at 1.5 T using usual protocols without specific absorption rate (SAR) restrictions. Nine PM-dependent patients were included. All devices were interrogated before and immediately after MRI. During the scan, pacing mode was programmed to asynchronous for PM-dependent patients whereas ICDs were programmed to a monitor-only mode. All devices were functioning appropriately after cardiac MRI. Comparison of device parameters obtained before and immediately after MRI revealed no significant changes in pacing threshold, lead impedance, battery status, or sensing signal amplitude. Neither clinical events nor patient complaints were reported. Significant imaging artefacts were present on 11 of 39 scans (28.2%). These artefacts were significantly more frequent in ICDs (8 of 8, 100%) vs. PMs (3 of 31, 9.7%) (P < 0.001). Diagnostic questions were answered in 92.3% of the cases, with just three pronounced artefacts preventing an adequate diagnosis in three ICD patients. CONCLUSIONS Our results suggest that cardiac MRI may be performed safely in appropriately selected patients with close monitoring during the scan without limitation of peak SAR level using several precautionary measures. Image artefacts were more frequent in ICD patients.

Incidence and predictors of clinically relevant cardiac perforation associated with systematic implantation of active-fixation pacing and defibrillation leads: a single-centre experience with over 3800 implanted leads

Aims Active-fixation leads have been associated with higher incidence of cardiac perforation. Large series specifically evaluating this complication are lacking. We sought to evaluate the incidence and predictors of clinically relevant cardiac perforation in a consecutive series of patients implanted with active-fixation pacing and defibrillation leads. Methods and results We conducted a retrospective observational study including all consecutive patients implanted with an active-fixation pacing/defibrillation lead at our institution from July 2008 to July 2015. The incidence of clinically relevant cardiac perforation and cardiac tamponade was evaluated. Univariate and multivariate analyses were used to identify predictors of cardiac perforation. Acute and long-term management of these patients was also investigated. A total of 3822 active-fixation pacing (n = 3035) and defibrillation (n = 787) leads were implanted in 2200 patients. Seventeen patients (0.8%) had clinically relevant cardiac perforation (13 acute and 4 subacute perforations), and 13 (0.5%) had cardiac tamponade resolved with pericardiocentesis. None of the patients with cardiac perforation required surgical treatment. In multivariate analysis, an age >80 years (OR 3.84, 95% CI 1.14–12.87, P = 0.029), female sex (OR 3.14, 95% CI 1.07–9.22, P = 0.037), and an apical position of the right ventricular lead (OR 3.37, 95% CI 1.17–9.67, P = 0.024) were independent predictors of cardiac perforation. Conclusions Implantation of active-fixation leads is associated with a low incidence of clinically relevant cardiac perforation. Older and female patients have a higher risk of perforation as well as those patients receiving the ventricular lead in an apical position.

The use of multisite left ventricular pacing via quadripolar lead improves acute haemodynamics and mechanical dyssynchrony assessed by radial strain speckle tracking: initial results.

AIMS The objective of the present study was to evaluate the effect of multipoint pacing (MPP) on acute haemodynamics, cardiac contractility, and left ventricle (LV) dyssynchrony, in comparison with conventional cardiac resynchronization therapy (CRT). METHODS AND RESULTS An open-label, non-randomized, single-centre, prospective study was designed. Twenty-seven consecutive patients were included. Evaluation of pacing configurations was performed in a random order. Transthoracic echocardiography was used to obtain haemodynamic and dyssynchrony parameters. Left ventricular ejection fraction (LVEF) was significantly superior in MPP compared with baseline (38.4 ± 1.8% vs. 26.1 ± 2.2%; P < 0.001), and in conventional pacing configuration compared with baseline (33.2 ± 1.8% vs. 26.1 ± 2.2%; P = 0.007). Cardiac index (CI) was increased by 21.8 ± 5.4% and 34.7 ± 5.1% in conventional and MPP configurations, respectively (P = 0.19). Percentage of acute responders (CI increase ≥10%) was 62.9 and 85.2% in conventional and MPP, respectively (P < 0.001). LV dyssynchrony was defined by radial strain rate parameters. Baseline anteroseptal-to-posterior wall time delay was 168 ± 21 ms. It was reduced until 70.4 ± 29 ms in conventional and -6.6 ± 11 ms in MPP (conventional vs. baseline P = 0.04; MPP vs. conventional P = 0.05). Standard deviation of the time-to-peak radial strain of the 6 LV basal segments was 101 ± 9.7, 80.3 ± 9.2, and 66 ± 8.03 ms in baseline, conventional, and MPP configurations, respectively (MPP vs. basal P = 0.012). Finally, we observed a positive correlation (r = 0.69) between reduction in dyssynchrony and CI increase (P < 0.0001). CONCLUSION MPP showed a further reduction in LV dyssynchrony compared with conventional biventricular pacing. Moreover, MPP resulted in an additional improvement in LVEF and in CI, and this was translated into a higher number of acute responders to CRT.

Resonancia magnética nuclear en pacientes portadores de dispositivos de estimulación cardiaca

La resonancia magnetica esta actualmente contraindicada a los pacientes portadores de dispositivos de estimulacion cardiaca. Ante la necesidad de concretar los riesgos potenciales derivados de esta situacion, surgio este estudio. De forma prospectiva, se evaluaron parametros clinicos, electricos y tecnicos antes y despues de la realizacion de la prueba en 33 pacientes (5 desfibriladores automaticos implantables, 28 marcapasos), en los que se considero clinicamente indispensable realizarla. No se apreciaron complicaciones clinicas. Se detectaron dos casos de fallo temporal de telemetria, dos errores de deteccion durante la exploracion y una respuesta de seguridad en un marcapasos a frecuencia magnetica y salida maxima. No hubo limitaciones tecnicas en la adquisicion de imagenes ni alteraciones permanentes del funcionamiento de los dispositivos de estimulacion cardiaca.

Nuclear Magnetic Resonance Imaging in Patients With Cardiac Pacing Devices

Currently, nuclear magnetic resonance imaging is contraindicated in patients with a pacemaker or implantable cardioverter-defibrillator. This study was carried out because the potential risks in this situation need to be clearly defined. This prospective study evaluated clinical and electrical parameters before and after magnetic resonance imaging was performed in 33 patients (five with implantable cardioverter-defibrillators and 28 with pacemakers). In these patients, magnetic resonance imaging was considered clinically essential. There were no clinical complications. There was a temporary communication failure in two cases, sensing errors during imaging in two cases, and a safety signal was generated in one pacemaker at the maximum magnetic resonance frequency and output level. There were no technical restrictions on imaging nor were there any permanent changes in the performance of the cardiac pacing device.

Technical Reliability and Clinical Safety of a Remote Monitoring System for Antiarrhythmic Cardiac Devices

INTRODUCTION AND OBJECTIVES In recent years, physicians have experienced a huge increase in workload associated with cardiac devices. Remote monitoring enables these devices to be monitored at a distance and could reduce the number of hospital visits. The aim of this study was to assess the technical reliability and clinical safety of the Home MonitoringTM remote monitoring system (Biotronik GmbH, Germany). METHODS The study included 162 patients: 115 with pacemakers, 44 with implantable cardioverter-defibrillators (ICDs) and three with ICDs incorporating cardiac resynchronization therapy (CRT). Patients were followed up for a mean of 303+/-244 days. We compared the survival time free of event alerts in patients with pacemakers and in those with ICDs. The remote monitoring systems reliability was evaluated by comparing the data it transmitted with clinical observations made immediately afterwards. RESULTS The mean percentage of days monitored was 88.2%. The incidence of event alerts was higher in pacemaker than ICD patients (45% vs. 34%; P=.01). Event alerts preceded the following hospital visit by 76+/-47 days. In the ICD group, the data sent by the monitoring system were judged as true-positives in 42% of cases, as true-negatives in 57% and as false-positives in 1%. No false-negative was observed. In the ICD group, the remote monitoring system had a sensitivity of 100% and a specificity of 97% (positive predictive value 96%, negative predictive value 100%). CONCLUSIONS Remote monitoring was a reliable and safe method for following up patients with cardiac devices. Its routine use could enable the early detection of device malfunctions or arrhythmic events.

Electrodo de desfibrilación Sprint Fidelis: experiencia de nueve centros en España

INTRODUCTION AND OBJECTIVES Sprint Fidelis defibrillation leads are prone to early failure. Most of the reported series come from a single institution. This paper describes the clinical experience in nine Spanish hospitals. METHODS Clinical, implant, and follow-up data of all patients with a Sprint Fidelis lead were analyzed. All cases of lead failure were identified, medium-term lead survival was calculated, and possible predictors for lead failure were determined. RESULTS In total, 378 leads in 376 patients were studied. The mean age (male 85.7%) was 64.9 ± 13.6 years. The majority of patients (59.8%) had ischemic heart disease. Mean left ventricular ejection fraction was 33.4% ± 14.5%. Left subclavian vein puncture was used in 74.8%. During a mean follow-up of 30.9 ± 14 months, 16 lead failures have occurred, with a lead survival of 96.1% at 36 months after implantation. Eleven of 16 lead failures were caused by failure of pace/sense conductors, 3 by defects in the high-voltage conductor, and 2 by defects in both types of conductors. A less depressed left ventricular ejection fraction was associated with an increased probability of lead failure (42.4% ± 16% vs. 33% ± 14.3%; P =.011). Three hospitals presented a rate of lead failure higher than 10%; the rate was less than 5% in the remaining 6 hospitals. CONCLUSIONS In this multicenter series of 378 leads, the 3-year estimated survival was higher than that reported in prior series. Clinical presentation of lead failures was similar to that reported previously. Left ventricular ejection fraction and hospital of implantation were variables associated to lead failure.

Safety and Feasibility of a Minimally Fluoroscopic Approach for Ventricular Tachycardia Ablation in Patients With Structural Heart Disease Influence of the Ventricular Tachycardia Substrate

Background—We sought to evaluate the safety and feasibility of a minimally fluoroscopic approach using the CARTOUNIVU module during scar-related ventricular tachycardia (VT) ablation. Methods and Results—Consecutive patients with structural heart disease undergoing VT ablation using the CARTOUNIVU module were prospectively included and classified depending on their VT substrate: (1) ischemic VT (IVT) and (2) nonischemic VT and depending on the presence of an epicardial access. Radiation exposure parameters and major and minor procedure-related complications were registered. A near-zero fluoroscopy exposure was defined as those procedures with an effective dose ⩽1 mSv. A total of 44 VT ablation procedures were performed in 41 patients (22 IVT and 19 nonischemic VT). The use of the CARTOUNIVU module resulted in low levels of radiation exposure: median total fluoroscopy time and effective dose of 6.08 (1.51–12.36) minutes and 2.15 (0.58–8.22) mSv, respectively. Patients with IVT had lower radiation exposure than patients with nonischemic VT (total fluoroscopy time, 2.53 [1.22–11.22] versus 8.51 [5.55–17.34] minutes; P=0.016). Epicardial access was associated with significantly higher levels of radiation exposure. Complications occurred in 4.9% patients, none of them being related to the use of the image integration tool. A near-zero fluoroscopy ablation could be performed in 14 of 44 procedures (32%), 43% of IVT procedures, and 50% of procedures with endocardial access only. Conclusions—The use of the CARTOUNIVU module during scar-related VT ablation resulted in low levels of radiation exposure. A near-zero fluoroscopy approach can be achieved in up to half of the procedures, especially in IVT patients with endocardial ablation.