Large Controlled Observational Study on Remote Monitoring of Pacemakers and Implantable Cardiac Defibrillators: A Clinical, Economic, and Organizational Evaluation.

BACKGROUND: Patients with implantable devices such as pacemakers (PMs) and implantable cardiac defibrillators (ICDs) should be followed up every 3-12 months, which traditionally required in-clinic visits. Innovative devices allow data transmission and technical or medical alerts to be sent from the patient's home to the physician (remote monitoring). A number of studies have shown its effectiveness in timely detection and management of both clinical and technical events, and endorsed its adoption. Unfortunately, in daily practice, remote monitoring has been implemented in uncoordinated and rather fragmented ways, calling for a more strategic approach. OBJECTIVE: The objective of the study was to analyze the impact of remote monitoring for PM and ICD in a "real world" context compared with in-clinic follow-up. The evaluation focuses on how this service is carried out by Local Health Authorities, the impact on the cardiology unit and the health system, and organizational features promoting or hindering its effectiveness and efficiency. METHODS: A multi-center, multi-vendor, controlled, observational, prospective study was conducted to analyze the impact of remote monitoring implementation. A total of 2101 patients were enrolled in the study: 1871 patients were followed through remote monitoring of PM/ICD (I-group) and 230 through in-clinic visits (U-group). The follow-up period was 12 months. RESULTS: In-clinic device follow-ups and cardiac visits were significantly lower in the I-group compared with the U-group, respectively: PM, I-group = 0.43, U-group = 1.07, P<.001; ICD, I-group = 0.98, U-group = 2.14, P<.001. PM, I-group = 0.37, U-group = 0.85, P<.001; ICD, I-group = 1.58, U-group = 1.69, P=.01. Hospitalizations for any cause were significantly lower in the I-group for PM patients only (I-group = 0.37, U-group = 0.50, P=.005). There were no significant differences regarding use of the emergency department for both PM and ICD patients. In the I-group, 0.30 (PM) and 0.37 (ICD) real clinical events per patient per year were detected within a mean (SD) time of 1.18 (2.08) days. Mean time spent by physicians to treat a patient was lower in the I-group compared to the U-group (-4.1 minutes PM; -13.7 minutes ICD). Organizational analysis showed that remote monitoring implementation was rather haphazard and fragmented. From a health care system perspective, the economic analysis showed statistically significant gains (P<.001) for the I-group using PM. CONCLUSIONS: This study contributes to build solid evidence regarding the usefulness of RM in detecting and managing clinical and technical events with limited use of manpower and other health care resources. To fully gain the benefits of RM of PM/ICD, it is vital that organizational processes be streamlined and standardized within an overarching strategy.

Long-term clinical outcome of patients who failed catheter ablation of atrial fibrillation.

AIMS: Left atrial ablation fails to prevent symptomatic recurrences of atrial fibrillation (AF) in 20-30% of patients up to 3 years of follow-up despite multiple procedures. Data are lacking on the long-term clinical outcome of those patients for whom the decision was taken to renounce performing further ablation procedures. METHODS AND RESULTS: In this multicentre study, 218 (34%) of 631 consecutive patients, who had undergone AF catheter ablation in the years 2001-11 for drug-refractory symptomatic AF, had symptomatic AF recurrences after 1.5 ± 0.6 procedures. Their long-term clinical outcome was assessed in March 2012 (minimum follow-up 1 year). At a mean of 5.1 ± 2.6 years since their last ablation, 82 (38%) patients improved, 103 (47%) remained unchanged and 33 (15%) worsened, but only 17 (8%) had such a severe impairment of their quality of life as to require atrioventricular junction ablation and pacing (#13) or cardiac surgery (#4); 22 (10%) patients had had adverse clinical events (death in five, heart failure in five, stroke and transient ischaemic cerebral attack in four, severe haemorrhage in four, pacemaker or implantable cardioverter-defibrillator implantation in seven) and 98 (45%) patients had developed permanent AF. Compared with patients without permanent AF, fewer patients with permanent AF improved (3% vs. 66%, P = 0.001) and more got worse (28% vs. 5%, P = 0.001). At multivariable logistic regression, single ablation procedure, left atrial diameter, persistent AF and time from the last ablation were independent predictors of permanent AF. CONCLUSION: More than 5 years after a failed AF ablation, a small minority of patients had such an impaired quality of life as to require non-pharmacological interventions. Almost half developed permanent AF, which significantly impaired quality of life. Permanent AF was more common in patients who had left atrial enlargement, history of persistent AF, longer follow-up, and had performed a single ablation procedure, thus hypothesizing that reablation could reduce the chronicization of arrhythmia. A low risk of stroke was observed in the long-term follow-up.

Late atrial tachycardia following pulmonary vein isolation: analysis of successful discrete ablation sites.

BACKGROUND: The role of additional left atrial linear lesions performed during pulmonary vein isolation (PVI) to prevent atrial tachycardias (ATs) is not yet clear. OBJECTIVE: To analyse successful ablation sites of late-onset post-PVI AT, and to understand whether additional ablation lines at mitral isthmus and left atrium (LA) roof could have been useful in preventing these jatrogenic ATs. METHODS: From March, 2002 to August, 2008, 366 patients underwent PVI alone for drug-refractory atrial fibrillation (AF). Twenty-six (7.1%) of these patients developed late AT during follow-up, and were referred for ablation. Successful discrete ablation sites were analysed. In no patient the index AT was terminated by a linear lesion in mitral isthmus or LA roof. RESULTS: Twenty-seven ATs were mapped; mean CL was 261 ± 71.6 ms. In 3/26 patients (11.5%), mapping was unsuccessful, while 23/26 (88.5%) patients underwent a successful procedure (24 AT morphologies in 23 patients - 3/24 were mapped as mitral isthmus, and 1/24, as LA roof-dependent AT). Among the 24 successfully mapped ATs, 17/24 (70.8%) displayed a macroreentrant activation and the remaining 7/24 (29.1%), a focal pattern. Finally, in 22/26 (84.6%) patients, ATs were no more inducible. At a mean f/u of 22.4 ± 12.2 months, 23/26 (88.4%) patients remained AT-free (antiarrhythmic drugs prescribed in 5/26, 19.2% patients for AF prevention). CONCLUSIONS: In our case series, less than one-fifth of late-onset post-PVI ATs were mapped as mitral isthmus- or LA roof-dependent circuits.

Straight screw-in atrial leads "J-post shaped" in right appendage versus J-shaped systems for permanent atrial pacing: a safety comparison.

BACKGROUND AND OBJECTIVES: The reliability of active-fixation atrial leads has been compared with that of passive-fixation leads; comparisons have also been made between straight and J-shaped screw-in lead systems. However, few data are available on procedural and short-term safety. This retrospective study compared the procedural safety of non-pre-shaped screw-in leads with that of passive- and active-fixation J-shaped leads. PATIENTS AND METHODS: From January 2004 to January 2010, 1,464 patients underwent new pacemaker/implantable cardioverter-defibrillator implantation. Of these, 915 (study population) received a passive- or active-fixation pre-J-shaped lead, or a straight screw-in atrial lead; the remaining 549 patients, who received only a ventricular lead, were excluded. The three study groups were: Group S-FIX (165 patients, 18%), receiving a straight screw-in atrial lead (postshaped in the right appendage); Group J-PASS (690 patients, 75.4%), receiving a passive-fixation J-shaped atrial lead; and Group J-FIX (60 patients, 6.6%), receiving an active-fixation screw-in J-shaped atrial lead. Procedural and short-term complication rates were analyzed up to 3 months postimplantation. RESULTS: One complication occurred in each group (S-FIX 0.6% vs J-PASS 0.1% vs J-FIX 1.6%, P = 0.3, 0.1, and 0.4, respectively, for each comparison). The rate of atrial lead dislodgement was higher in Group J-PASS than in S-FIX but not J-FIX (Group S-FIX 0 vs Group J-PASS 16 vs Group J-FIX 1 dislodgements; P = 0.04 and 0.7, respectively). CONCLUSION: Straight screw-in atrial leads, "J-post shaped" in the right appendage, offer better stability than passive-fixation J-shaped leads and display a similarly acceptable safety profile compared with both the J-shaped systems.

Integration of three-dimensional left atrial magnetic resonance images into a real-time electroanatomic mapping system: validation of a registration method.

BACKGROUND: The alignment of three-dimensional (3D) left atrial images acquired by magnetic resonance (MR) with the anatomical information yielded by 3D mapping systems is one of the most critical issues in image integration techniques for catheter ablation of atrial fibrillation (AF). We assessed the accuracy of a simplified method of superimposing 3D MR left atrial images on real-time left atrial electroanatomic maps (registration). METHODS: MR data on the left atrium in 40 patients with drug-refractory AF were imported into the CartoMerge (Biosense Webster, Inc., Diamond Bar, CA, USA) electroanatomic mapping system. Registration was obtained by combining "visual alignment" of one endocardial point and "surface registration" of a limited number of points sampled on the posterior wall of the left atrium. The accuracy of the registration process was assessed through a statistical algorithm incorporated into the CartoMerge system, and through the percentage of pulmonary veins (PVs) in which electrical isolation was achieved after anatomical ablation. RESULTS: The mean registration surface-to-point distance and ablation surface-to-point distance were 1.33 +/- 0.96 mm and 1.47 +/- 1.15 mm, respectively. Upon completion of the circumferential anatomical ablation around the PVs, electrical PV isolation was confirmed by a multipolar circular mapping catheter in 129 of 146 PVs (89%). CONCLUSIONS: Our registration method, which is mainly based on the surface registration of the posterior wall of the left atrium, enables almost 90% of PVs to be isolated by means of an anatomically based catheter ablation approach.

Atrio-ventricular block during left atrial flutter ablation.

We present a case of a patient treated with catheter ablation for atrial fibrillation aiming to pulmonary veins isolation. During ablation, atrial fibrillation organized into a left atrial flutter. Electroanatomic and electrophysiologic mapping revealed the anterior left atrium area between the mitral annulus and left atrium septum as a critical region for flutter ablation. After a few pulses of radiofrequency, complete atrio-ventricular block appeared. Finally, we propose pace mapping of the mitral annulus to detect left dislodgment of the compact atrio-ventricular node.