X-ray management in electrophysiology: a survey of the Italian Association of Arrhythmology and Cardiac Pacing (AIAC).

AIMS: Radiation use in medicine has significantly increased over the last decade, and cardiologists are among the specialists most responsible for X-ray exposure. The present study investigates a broad range of aspects, from specific European Union directives to general practical principles, related to radiation management among a national cohort of cardiologists. METHODS AND RESULTS: A voluntary 31-question survey was run on the Italian Arrhythmology and Pacing Society (AIAC) website. From June 2019 to January 2020, 125 cardiologists, routinely performing interventional electrophysiology, participated in the survey. Eighty-seven (70.2%) participants are aware of the recent European Directive (Euratom 2013/59), although only 35 (28.2%) declare to have read the document in detail. Ninety-six (77.4%) participants register the dose delivered to the patient in each procedure, in 66.1% of the cases both as fluoroscopy time and dose area product. Years of exposition (P = 0.009) and working in centers performing pediatric procedures (P = 0.021) related to greater degree of X-ray equipment optimization. The majority of participants (72, 58.1%) did not recently attend radioprotection courses. The latter is related to increased awareness of techniques to reduce radiation exposure (96% vs. 81%, P = 0.022), registration of the delivered dose in each procedure (92% vs. 67%, P = 0.009), and X-ray equipment optimization (50% vs. 36%, P = 0.006). CONCLUSION: Italian interventional cardiologists show an acceptable level of radiation awareness and knowledge of updated European directives. However, there is clear space for improvement. Comparison to other health professionals, both at national and international levels, is needed to pursue proper X-ray management and protect public health.

Accessory Pathway-Mediated Tachycardias: Precision Electrocardiology Through Standard and Advanced Electrocardiogram Recording Techniques.

An accessory pathway (AP) can be apparent during sinus rhythm if it depolarizes part of the ventricles ahead of the normal wave front from the conduction system. An AP can generate an anatomic circuit able to sustain a macroreentrant atrioventricular reentrant tachycardia. This arrhythmia can engage the normal conducting system in an antegrade direction or retrogradely, generating, respectively, a narrow or a wide complex tachycardia. The combined use of a standard electrocardiogram and an esophageal recording-pacing can be particularly useful in the first approach to patients with Wolff-Parkinson-White syndrome, further stratifying patients requiring electrophysiology study and transcatheter ablation.

Clinical Approach to Symptomatic and Asymptomatic Patients with Ventricular Pre-excitation.

Despite extensive knowledge of the physiopathology of ventricular pre-excitation, management of asymptomatic patients with this condition remains controversial.

Ablation of Accessory Pathways with Uncommon Electrophysiologic Properties.

In rare cases, atrioventricular reentrant arrhythmias are sustained by accessory pathways with peculiar electrophysiologic features that may be related to their specific anatomy. Most of these bundles show decremental nodelike conduction properties and sustain peculiar forms of arrhythmias that require careful differential diagnosis. On the other hand, some pathways do not actively sustain any reentrant circuit and should nevertheless be promptly recognized to avoid unnecessary ablation attempts. Although rare, these variants of accessory pathway should be known to warrant a safe and effective catheter ablation procedure.

Temporary transvenous cardiac pacing: a survey on current practice.

BACKGROUND: Temporary transvenous cardiac pacing (TTCP) is a standard procedure in current practice, despite limited coverage in consensus guidelines. However, many authors reported several complications associated with TTCP, especially development of infections of cardiac implantable electronic devices (CIED). The aim of this survey was to provide a country-wide picture of current practice regarding TTCP. METHODS: Data were collected using an online survey that was administered to members of the Italian Association of Arrhythmology and Cardiac Pacing. RESULTS: We collected data from 102 physicians, working in 81 Italian hospitals from 17/21 regions. Our data evidenced that different strategies are adopted in case of acute bradycardia with a tendency to limit TTCP mainly to advanced atrioventricular block. However, some centers reported a greater use in elective procedures. TTCP is usually performed by electrophysiologists or interventional cardiologists and, differently from previous reports, mainly by a femoral approach and with nonfloating catheters. We found high inhomogeneity regarding prevention of infections and thromboembolic complications and in post-TTCP management, associated with different TTCP volumes and a strategy for management of acute bradyarrhythmias. CONCLUSION: This survey evidenced a high inhomogeneity in the approaches adopted by Italian cardiologists for TTCP. Further studies are needed to explore if these divergences are associated with different long-term outcomes, especially incidence of CIED-related infections.

[2017 Catheter Ablation Registry of the Italian Association of Arrhythmology and Cardiac Pacing]. / Registro Italiano Ablazioni 2017. Associazione Italiana di Aritmologia e Cardiostimolazione.

BACKGROUND: This report describes the findings of the 2017 Catheter Ablation Registry of the Italian Association of Arrhythmology and Cardiac Pacing (AIAC). METHODS: Data collection was retrospective. A standardized questionnaire was completed by each of the participating centers. RESULTS: A total of 15 601 ablation procedures were performed by 91 institutions, with a mean of 184 ± 213 procedures per center. The most frequently treated arrhythmia was atrial fibrillation (34%), followed by atrioventricular nodal reentrant tachycardia (25%) and common atrial flutter (14%). About 10% of overall ablation procedures were performed in patients with ventricular arrhythmias. On-site cardiothoracic surgery was available in 42% of the centers performing ablation and in 49% of the centers performing atrial fibrillation ablation. In most patients, the ablation procedure was guided by a three-dimensional mapping system, and in 15% of patients a near-zero X-ray strategy was used. CONCLUSIONS: The Italian Catheter Ablation Registry systematically collected 1-year data on ablation procedures performed in Italy, revealing that atrial fibrillation is the most commonly treated arrhythmia in the ablation centers with an increasing number of patients treated for ventricular tachycardia.

Advanced Cardiac Signal Recording.

Implantable loop recorders allow prolonged and continuous single-lead electrocardiogram recording, with the pivotal addition of remote monitoring. They have significantly shortened time to electrocardiographic diagnosis and appropriate therapy of many bradyarrhythmias/tachyarrhythmias and proved helpful in arrhythmia burden definition, offering invaluable information in the diagnostic workup for syncope and atrial fibrillation. Advanced cardiac signal recording is also possible by transesophageal catheters. They have been used to orient diagnosis during wide and narrow QRS complex tachycardias and also to perform minimally invasive pacing. Intracardiac electrophysiologic study remains, however, essential for diagnosis of several arrhythmias in the perspective of curative catheter ablation.

Emerging therapeutic uses of direct-acting oral anticoagulants: An evidence-based perspective.

Direct-acting oral anticoagulants (DOACs) were claimed to cause a potential paradigm shift in the therapeutic scenario of patients requiring short- and long-term anticoagulation, by virtue of their pharmacological properties, perceived as innovative. The evidence gathered so far (from pre-approval pivotal trials to real-world post-marketing observational data) consistently confirmed that DOACs are overall comparable to vitamin-K antagonists (VKAs) in terms of safety, efficacy and effectiveness and unequivocally documented a consistent and clinically relevant reduced risk of intracranial bleeding in the settings of non-valvular atrial fibrillation (NVAF) and venous thromboembolism (VTE). Interestingly, two parallel paths can be identified in the current research scenario: A) in the aforementioned consolidated therapeutic indications, an innovative approach is directed towards tailored treatment strategies, to identify patients most likely to benefit from one of the different anticoagulant drugs, in particular subpopulations at increased risk of adverse events (e.g., bleeding); B) in unconventional settings, DOACs are gaining interest for potential use in emerging diseases characterized by arterial and venous thromboembolic risk. In these scenarios, the risk-benefit profile of DOACs, as compared to VKAs or heparins, is less defined. The aim of this review is to critically assess the body of evidence underlying emerging therapeutic uses of DOACs (e.g., heparin-induced thrombocytopenia, anti-phospholipid antibody syndrome), including evolving issues in special populations (e.g., patients with VTE and cancer or cirrhosis). This will be achieved by analyzing the strength (i.e., systematic reviews, randomized clinical trials, observational studies, case report/series) and consistency (i.e., concordance) of both published and unpublished evidence registered in major public repositories.

Invasive electrophysiological evaluation and ablation in patients with asymptomatic ventricular pre-excitation persistent at exercise stress test.

AIMS: In patients with asymptomatic ventricular pre-excitation (VPE) persistent at exercise stress test, this study evaluates the proportion of cases with adverse conduction properties of the atrioventricular accessory pathway (AP) at invasive electrophysiological study and the long-term follow-up after they received treatment according to pre-determined criteria. METHODS AND RESULTS: Over 10 years, asymptomatic patients with VPE persistent at exercise stress test referred for invasive electrophysiological evaluation including isoproterenol (IPN) infusion were included. Ablation was planned if they had at least one of the following criteria: (i) shortest pre-excited R-R interval (SPERRI) ≤250 ms and/or (ii) inducible atrioventricular re-entrant tachycardia (AVRT). Cryoablation was electively used in para-hisian and mid-septal APs. Patients non-eligible for ablation received no therapy. Sixty-three patients (45 males; mean age 26 ± 14 years) underwent electrophysiological evaluation: 7 had fasciculo-ventricular fibres and were excluded, whereas 56 had 58 APs. Thirty-one patients (55%) were eligible and underwent successful ablation: 87% had at least the SPERRI ≤ 250 ms and 61% had at least inducible AVRT. In 15 cases (48%) the ablation criteria were met only during IPN infusion. During follow-up (73 ± 33 months), one patient was successfully retreated for resumption of VPE in the ablation group, whereas no event was observed in the group of patients who received no treatment. CONCLUSION: In this subset of patients with asymptomatic VPE, invasive electrophysiological evaluation shows fast antegrade conduction over the AP and/or inducible AVRT in about half of the cases. Patients who received no therapy because of a benign electrophysiological profile had an event-free follow-up.

Simulator training reduces radiation exposure and improves trainees' performance in placing electrophysiologic catheters during patient-based procedures.

BACKGROUND: Currently, training in interventional electrophysiology is based on conventional methodologies, and a paucity of data on the usefulness of simulation in this field is available. OBJECTIVE: The purpose of this study was to evaluate the impact of simulator training on trainees' performance in electrophysiologic catheter placement during the early phase of their learning curve. METHODS: Inexperienced electrophysiology fellows were considered. A hybrid high-fidelity simulator (Procedicus VIST, version 7.0, Mentice AB Gothenburg, Sweden for Biosense Webster) was used. The following parameters were evaluated in 3 consecutive patient-based procedures before and after two training sessions of at least 1.5 hours on the simulator: (1) ability to place catheters in conventional recording/pacing sites (coronary sinus, His-bundle area, high right atrium, and right ventricular apex); (2) amount of help provided by the supervisor (scale from 1-3; 3 for maximal help); (3) fluoroscopy time; and (4) positioning time. RESULTS: Seven fellows performed 168 catheter placements during 42 patient-based procedures with no complications. Comparing parameters before and after simulator training, there was a significant reduction in the mean amount of help and in fluoroscopy and positioning times per placement: from 1.71 ± 1.24 to 0.42 ± 0.68 (P <.001), from 121 ± 88 seconds to 76 ± 54 seconds (P <.001), and from 175 ± 138 seconds to 102 ± 74 seconds (P <.001), respectively. Overall fluoroscopy time per patient decreased from 567 ± 220 seconds to 305 ± 111 seconds (P <.0001). Improvement appeared to be related to simulator training alone and not to the previously performed patient-based procedures. CONCLUSION: During the early phase of the trainees' learning curve, simulator training significantly improves the independent trainees' performance with reduction in radiation exposure.

Atrial tachycardias in patients with congenital heart disease: a minimally invasive simplified approach in the use of three-dimensional electroanatomic mapping.

AIMS: Atrial tachycardia (AT) is a common complication after repair of congenital heart disease (CHD). This two-centre prospective study evaluated the ability of three-dimensional electroanatomic mapping (EAM) to guide ablation of ATs in this particular population with a minimally invasive simplified approach. METHODS AND RESULTS: Thirty-one consecutive patients (mean age 26 ± 17 years) with AT after repair of CHD were treated with a very limited number of intracavitary catheters and a specific setting of the Window of Interest (WoI) for the ablation of post-surgical ATs. A single-intracavitary catheter approach was performed in 22 patients, whereas an overall use of two intracavitary catheters in the other nine patients. Thirty-one patients exhibited 41 ATs. Seventy-six per cent of these were macro-reentrant ATs (MRATs), and 24% were focal ATs (FAT). The mid-diastolic isthmus (MDI) was located in the right atrial free wall (RAFW) in 82.8% of MRATs. Also in FATs, the RAFW was the most common site (77.8%) of the ectopic focus. Fifty-eight per cent of MRATs showed a double-loop reentry, with both loops sharing the same MDI in all cases. In 87% of cases, the abolition of the MRAT was obtained by applying radiofrequency energy to the MDI. Ninety per cent of FATs were successfully ablated. Mean conduction velocity and voltage amplitude had significantly lower values in successfully treated than in unsuccessfully treated MRATs. CONCLUSION: Three-dimensional EAM, performed with a minimally invasive simplified approach and by using a specific parameter setting of the WoI, showed to be very effective to guide ablation of ATs in CHD patients.

Use of a novel sharp-tip, J-shaped guidewire to facilitate transseptal catheterization.

AIMS: Transseptal catheterization (TSP-C) is a demanding procedure and at the same time one of the key points of atrial fibrillation ablation, an increasingly diffused procedure. This study prospectively evaluates the usefulness of a novel sharp-tip, J-shaped 0.014'' transseptal guidewire (TSP-GW) to facilitate TSP-C in case of resistant atrial septum (AS). METHODS AND RESULTS: Consecutive patients undergoing TSP-C for arrhythmia ablation in a single centre were considered for the study. TSP-C was performed according to a standardized technique. The criterion to use the TSP-GW was a resistant AS, defined as inability to perforate the fossa ovalis by applying moderate pressure to a standard Brockenbrough needle. The TSP-GW was inserted in the needle lumen and advanced to puncture the AS and enter the left atrium; subsequently, the transseptal assembly was advanced over the TSP-GW. Double transseptal puncture was routinely performed for ablation of atrial fibrillation. Eighty-one patients (54 males, 27 females; mean age 54 +/- 17 years, range 12-81) undergoing TSP-C were enrolled; 132 TSP-C procedures were planned and accomplished. Nineteen patients (23%) in 27 procedures showed a resistant AS. In all these procedures, the TSP-GW was safely and successfully used to accomplish the TSP-C. In patients with a resistant AS, only a significantly lower prevalence of structural heart disease was observed when compared with controls. No complication related to TSP-C was observed. CONCLUSION: The TSP-GW facilitates TSP-C in 23% of the patients, in whom a resistant AS is encountered. In this population, there was no clinical predictor of such anatomy.

Treatment of macro-re-entrant atrial tachycardia based on electroanatomic mapping: identification and ablation of the mid-diastolic isthmus.

AIMS: This multicentre prospective study evaluated the ability of electroanatomic mapping (EAM) using a specific parameter setting to identify clearly the mid-diastolically activated isthmus (MDAI) and guide ablation of macro-re-entrant atrial tachycardia (MAT). METHODS AND RESULTS: Consecutive patients with MAT, different from typical isthmus-dependent atrial flutter, were enrolled. EAM was performed using a specific setting of the window of interest, calculated to identify the MDAI and guide ablation of this area. Sixty-five patients exhibiting 81 MATs (mean cycle length 308 +/- 68 ms) were considered. Thirty-two (49.2%) had previous heart surgery. In 79 of 81 morphologies (97.5%), EAM reconstructed 95.9 +/- 4.3% of the tachycardia circuit and identified the MDAI; 23 of the 79 morphologies (29.1%) were double-loop re-entry. Mapping of two morphologies was incomplete due to MAT termination after catheter bumping. In 73 of 79 mapped morphologies (92.4%), abolition of the MAT was obtained by 13.2 +/- 12.4 applications. During the 14 +/- 4 month follow-up, MAT recurred in 4 of the successfully treated patients (6.8%). CONCLUSION: EAM using a specific parameter setting proved highly effective at identifying the MDAI in MAT, even in patients with previous surgery and multiple re-entrant loops. Ablation of the MDAI yielded acute arrhythmia suppression with low rate of recurrence during follow-up.

Simultaneous dual fast and slow pathway conduction upon induction of typical atrioventricular nodal reentrant tachycardia: electrophysiologic characteristics in a series of patients.

INTRODUCTION: Simultaneous dual atrioventricular nodal conduction (SDNC) through slow (SP) and fast pathway (FP) is a rare phenomenon observed upon the induction of atrioventricular nodal reciprocating tachycardia (AVNRT). The aim of this study is to report the electrophysiological features of patients showing typical AVNRT induced through SDNC. METHODS AND RESULTS: Among 461 consecutive patients with typical AVNRT submitted to radiofrequency catheter ablation (RFCA), seven patients (1.5%) with SDNC at tachycardia onset (group I: 6 female; age 60-72 years, mean 65.2 +/- 3.8 years) and 118 age-matched controls (group II: 60 female; age 60-88 years, mean 68.4 +/- 6.8 years) were considered. Controls were further subdivided into two subgroups according to age: subgroup A (94 patients, age 60-75 years) and subgroup B (24 patients, age >75 years). The value of the following parameters was significantly higher in group I than in group II and in subgroup A: A-H interval [113 +/- 26 vs. 89 +/- 27 (P < 0.01) vs. 84 +/- 19 (P < 0.001)], ventriculoatrial conduction effective refractory period [355 +/- 85 vs. 293 +/- 87 (P < 0.05) vs. 281 +/- 82 (P < 0.05)], SP conduction time upon AVNRT induction [444 +/- 104 vs. 350 +/- 72 (P < 0.01); vs. 345 +/- 67 (P < 0.001)], AVNRT cycle length [484 +/- 103 vs. 396 +/- 71 ms (P < 0.05); vs. 384 +/- 69 (P < 0.05)], and rate of AVNRT induction from ventricle [71% vs. 10% (P = 0.001); vs. 6% (P = 0.001)]. Differences were mostly not significant between group I and subgroup B. SP location and RFCA success rate were similar in all groups. CONCLUSION: In a population of AVNRT patients, SDNC at AVNRT induction is infrequent and it prevails beyond the fifth decade of life and in females. SDNC is associated with peculiar AVN conduction features, which resemble the age-related modifications of AVN conduction.

Computerized high-density mapping of the pulmonary veins: new insights into their electrical activation in patients with atrial fibrillation.

AIM: To report the method and findings of computerized high-density mapping of pulmonary veins (PVs) in patients undergoing their electrical isolation for atrial fibrillation (AF). METHODS AND RESULTS: In 17 consecutive patients (8 M, age 55+/-11 years), a 64 electrode basket catheter was placed in the target PVs and 56 bipolar electrograms were recorded, analyzed and isochronal maps were generated. PVs were mapped during sinus rhythm, left-sided pacing and ectopic activity. The sites of earliest activation at the veno-atrial junction were defined as the atrium to vein conduction breakthroughs. PV activation pattern was classified as predominantly longitudinal or transverse, according to the direction of the impulse from the breakthroughs. The ectopic pattern was defined as multifocal, when distant areas in the PV had activation times within 10ms. Thirty-one PVs were mapped. The activation pattern was predominantly longitudinal in 13 PVs and transverse in 18 PVs. Two breakthroughs were identified in 22 PVs and three in nine. All the breakthroughs were evident simultaneously in sinus rhythm and left-sided pacing changed only the predominance of the breakthrough. Ectopies were mapped in 10 PVs: eight showed a multifocal and two a monofocal pattern; six ectopies originated from the proximal tract of the PV. CONCLUSION: High-density mapping of PV identifies a typical activation pattern. Multiple and discrete breakthroughs are simultaneously identified in sinus rhythm. The majority of the mapped ectopies has a multifocal pattern and proximal origin.