Transcatheter options for atrial fibrillation treatment: an overview of the ablative techniques currently available and future perspectives.

Atrial fibrillation (AF) is the most common arrhythmia in the adult population and catheter ablation has emerged as an important rhythm-control strategy and is the most common cardiac ablation procedure performed worldwide. The antiarrhythmic drugs have demonstrated moderate efficacy in long-term maintenance of sinus rhythm; moreover, they are often not tolerated and are associated with adverse events. Catheter ablation has proven to be effective in treating AF, although long-term outcomes have been significantly less favorable in persistent AF than in paroxysmal. The current guidelines recommend catheter ablation as class I indication for patients whom antiarrhythmic drugs have failed or are not tolerated, and as first-line rhythm-control therapy in selected patients with symptomatic AF. Advances in technology and innovative ablation protocols resulted in a remarkable improvement of the efficacy outcomes after pulmonary vein isolation. This review seeks to provide an updated report of the current practices and approaches, and to describe the latest advances in technology that aim to improve procedural safety, efficacy and to reduce procedural requirements in terms of duration and fluoroscopy exposure.

Arrhythmic risk profile in mitral valve prolapse: A systematic review and metanalysis of 1715 patients.

INTRODUCTION: Mitral valve prolapse (MVP) is a common clinical condition in the general population. A subgroup of patients with MVP may experience ventricular arrhythmias and sudden cardiac death ("arrhythmic mitral valve prolapse" [AMVP]) but how to stratify arrhythmic risk is still unclear. Our meta-analysis aims to identify predictive factors for arrhythmic risk in patients with MVP. METHODS: We systematically searched Medline, Cochrane, Journals@Ovid, Scopus electronic databases for studies published up to December 28, 2022 and comparing AMVP and nonarrhythmic mitral valve prolapse (NAMVP) for what concerns history, electrocardiographic, echocardiographic and cardiac magnetic resonance features. The effect size was estimated using a random-effect model as odds ratio (OR) and mean difference (MD). RESULTS: A total of 10 studies enrolling 1715 patients were included. Late gadolinium enhancement (LGE) (OR: 16.67; p = .005), T-wave inversion (TWI) (OR: 2.63; p < .0001), bileaflet MVP (OR: 1.92; p < .0001) and mitral anulus disjunction (MAD) (OR: 2.60; p < .0001) were more represented among patients with AMVP than in NAMVP. Patients with AMVP were shown to have longer anterior mitral leaflet (AML) (MD: 2.63 mm; p < .0001), posterior mitral leaflet (MD: 2.96 mm; p < .0001), thicker AML (MD: 0.49 mm; p < .0001), longer MAD length (MD: 1.24 mm; p < .0001) and higher amount of LGE (MD: 1.41%; p < .0001) than NAMVP. AMVP showed increased mechanical dispersion (MD: 8.04 ms; 95% confidence interval: 5.13-10.96; p < .0001) compared with NAMVP. CONCLUSIONS: Our meta-analysis proved that LGE, TWI, bileaflet MVP, and MAD are predictive factors for arrhythmic risk in MVP patients.

Impact of first-line cryoablation for atrial fibrillation on healthcare utilization, arrhythmia disease burden and efficacy outcomes: real-world evidence from the Cryo Global Registry.

BACKGROUND: Cryoballoon ablation (CBA) is an effective first-line treatment for symptomatic atrial fibrillation (AF), as recently demonstrated by three randomized trials. This sub-analysis of the Cryo Global Registry aims to examine current clinical practices of first-line CBA. METHODS: AF patients treated with first-line CBA were compared to CBA in antiarrhythmic drug (AAD)-refractory patients at 12 months. Efficacy was examined using time-to-first atrial arrhythmia recurrence following a 90-day blanking period. Healthcare utilization was evaluated by repeat ablations and hospitalizations. Disease burden was examined by assessing quality of life (QOL) and patients' reporting of symptoms. RESULTS: Of 1394 patients, 433 (31.1%) were treated with first-line CBA, which was more frequent in high-volume centers. Serious procedure-related adverse event rates were similar. Efficacy at 12 months was higher in the first-line group (87.8 vs. 81.6%, HRunadj 0.64 (95% CI 0.47-0.88); p < 0.01) regardless of the centers' CBA experience; when controlling for baseline characteristics, the difference was not significant (HRadj 0.87 (95% CI 0.56-1.37); p = 0.55). No difference was observed in repeat ablations and hospitalizations between cohorts. First-line patients experienced a larger mean reduction in symptoms and were prescribed AADs at a lower rate at 12-month follow-up (9.7 vs. 29.9%). QOL improved in both cohorts from baseline to 12 months with no significant difference between groups (p = 0.29). CONCLUSIONS: In this global real-world experience, first-line CBA in patients with symptomatic AF is effective, with a larger symptom reduction compared with CBA after AAD failure and without a difference in healthcare utilization at mid-term follow-up. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT02752737.

Standard versus strict stability criteria in radiofrequency paroxysmal atrial fibrillation ablation using ablation index.

PURPOSE: To compare the outcome of paroxysmal atrial fibrillation (AF) ablation via pulmonary vein isolation using Ablation Index (AI) with strict or standard stability criteria. METHODS: We enrolled 130 consecutive naive patients affected by paroxysmal AF who underwent PVI at two high-volume centers. AI target was ≥380 at the posterior wall and ≥500 at the anterior wall. Strict versus standard stability criteria were set for Group 1 (65 patients) and Group 2 (65 patients), respectively. We compared those strategies with a historical cohort of 72 consecutive patients treated at same centers in the VISITALY study, using average force ≥10 g and strict stability criteria as target parameters. Interlesion distance target was <6 mm. Recurrence was defined as any AF, atrial tachycardia (AT) or atrial flutter (AFL) during the 12 months after ablation, excluding a 90-days blanking period. RESULTS: Procedure duration (224.05 ± 47.21 vs. 175.61 ± 51.29 min; p < .001), fluoroscopy time (11.85 ± 4.38 vs. 10.46 ± 6.49 min; p = .019) and pericardial effusion rate (9.23% vs. 0%; p = .01) were higher in Group 1 than in Group 2. Freedom from AF/AT/AFL at 12 months was not significantly different (Group 1: 86.15%; Group 2: 90.77%; p = .42). Compared to VISITALY study, there were not significant differences in terms of recurrences. CONCLUSION: A strategy of PVI using AI with standard stability criteria performed the best in terms of procedure efficiency and safety. Twelve-months arrhythmia-free survival rate was comparable with other strategies pursuing an interlesion distance target <6 mm, regardless of the use of AI.

Safety of cryoballoon ablation for the treatment of atrial fibrillation: First European results from the cryo AF Global Registry.

BACKGROUND: Cryoballoon ablation for the treatment of patients with atrial fibrillation (AF) has been utilized in Europe for >15 years. OBJECTIVES: Report patient and procedural characteristics that influence the safety of cryoablation for the treatment of AF. METHODS: Patients enrolled in the prospective, multicenter Cryo AF Global Registry were treated at 38 European centers. Freedom from a ≥30s episode of AF/atrial flutter (AFL)/atrial tachycardia (AT) at 12-months and serious complications were analyzed. Univariate and multivariable models identified baseline patient and procedural characteristics that predicted a procedure-related complication. RESULTS: Of the 1418 subjects who completed an index procedure, the cohort was 62 ± 11 years of age, 37.7% female, and 72.2% paroxysmal AF (PAF). The mean procedure, left atrial dwell, and fluoroscopy times were 81 ± 34, 54 ± 25, and 14 ± 13 min, respectively. Among the 766 patients with 12-month follow-up, freedom from a ≥30 s AF/AFL/AT recurrence was 83.3% (95% CI: 79.8%-86.3%) and 71.6% (95% CI: 64.6%-77.4%) in patients with PAF and persistent AF. The serious procedure- and device-related adverse event rates were 4.7% and 2.0%. No baseline patient characteristic independently predicted a procedure-related adverse event; however, prolonged procedure duration (OR = 1.01 [95% CI: 1.00-1.01]), use of general anesthesia (OR = 1.71 [95% CI: 1.01-2.92]), and delivery of a cavotricuspid isthmus line (OR = 3.04 [95% CI: 1.01-9.20]) were each independently associated with the occurrence of a serious procedural safety event (all p < .05). CONCLUSIONS: Cryoballoon ablation is safe and effective in real-world use across a broad cohort of patients with AF.

Role of pre-procedural CT imaging on catheter ablation in patients with atrial fibrillation: procedural outcomes and radiological exposure.

BACKGROUND: Cardiac computed tomography (CT) is commonly used to study left atrial (LA) and pulmonary veins (PVs) anatomy before atrial fibrillation (AF) ablation. The aim of the study was to determine the impact of pre-procedural cardiac CT with 3D reconstruction on procedural outcomes and radiological exposure in patients who underwent radiofrequency catheter ablation (RFA) of AF. METHODS: In this registry, 493 consecutive patients (age 62 ± 8 years, 70% male) with paroxysmal (316) or persistent (177) AF who underwent first procedure of RFA were included. A pre-procedural CT scan was obtained in 324 patients (CT group). Antral pulmonary vein isolation was performed in all patients using an open-irrigation-tip catheter with a 3D electroanatomical navigation system. Procedural outcome, including radiological exposure, and clinical outcomes were compared among patients who underwent RFA with (CT group) and without (no CT group) pre-procedural cardiac CT. RESULTS: Acute PV isolation was obtained in all patients, with a comparable overall complication rate between CT and no CT group (4.3% vs 3%, p = 0.7). No differences were observed about mean duration of the procedure (231 ± 60 vs 233 ± 58 min, p = 0.7) and fluoroscopy time (13 ± 10 vs 13 ± 8 min, p = 0.6) among groups. Cumulative radiation dose resulted significantly higher in the CT group compared with no CT group (8.9 ± 24 vs 4.8 ± 15 mSv, P = 0.02). At 1 year, freedom from AF/atrial tachycardia were comparable among groups (CT group, 227/324 (70%), vs no CT group,119/169 (70%), p = ns). CONCLUSIONS: Pre-procedural CT does not improve safety and efficacy of AF ablation, increasing significantly the cumulative radiological exposure.

Predictors of zero X ray procedures in supraventricular arrhythmias ablation.

To evaluate predictors of zero-X ray procedures for supraventricular arrhythmias (SVT) using minimally fluoroscopic approach (MFA). Patients referred for RF catheter ablation of SVT were admitted for a MFA with an electro-anatomical navigation system or a conventional fluoroscopic approach (ConvA). Exclusion criterion was the need to perform a transseptal puncture. 206 patients (98 men, age 53 ± 19 years) underwent an EP study, 93 (45%) with an MFA and 113 (55%) with a ConvA. Fifty-five had no inducible arrhythmias (EPS). Fifty-four had AV nodal reentrant tachycardia (AVNRT), 49 patients had typical atrial flutter (AFL), 37 had AV reciprocating tachycardia (AVRT/WPW), 11 had focal atrial tachycardia (AT), and underwent a RF ablation. X-ray was not used at all in 51/93 (58%) procedures (zero X ray). MFA was associated with a significant reduction in total fluoroscopy time (5.5 ± 10 vs 13 ± 18 min, P = 0.01) and operator radiation dose (0.8 ± 2.5 vs 3 ± 8.2 mSV, P < 0.05). The greatest absolute dose reduction was observed in AVNRT (0.1 ± 0.3 vs 5.1 ± 10 mSV, P = 0.01, 98% relative dose reduction) and in AFL (1.3 ± 3.6 vs 11 ± 16 mSV, P = 0.003, 88% relative dose reduction) groups. Both AVNRT or AFL resulted the only statistically significant predictors of zero x ray at multivariate analysis (OR 4.5, 95% CI 1.5-13 and OR 5, 95% CI 1.7-15, P < 0.001, respectively). Success and complication rate was comparable between groups (P = NS). Using MFA for SVT ablation, radiological exposure is significantly reduced. Type of arrhythmia is the strongest predictor of zero X ray procedure.

Micra pacemaker implant after cardiac implantable electronic device extraction: feasibility and long-term outcomes.

AIMS: We aimed at investigating the feasibility and outcome of Micra implant in patients who have previously undergone transvenous lead extraction (TLE), in comparison to naïve patients implanted with the same device. METHODS AND RESULTS: Eighty-three patients (65 males, 78.31%; 77.27 ± 9.96 years) underwent Micra implant at our centre. The entire cohort was divided between 'post-extraction' (Group 1) and naïve patients (Group 2). In 23 of 83 patients (20 males, 86.96%; 73.83 ± 10.29 years), Micra was implanted after TLE. Indication to TLE was an infection in 15 patients (65.21%), leads malfunction in four (17.39%), superior vena cava syndrome in three (13.05%), and severe tricuspid regurgitation in one case (4.35%). The implant procedure was successful in all patients and no device-related events occurred at follow-up (median: 18 months; interquartile range: 1-24). No differences were observed between groups in fluoroscopy time (13.88 ± 10.98 min vs. 13.15 ± 6.64 min, P = 0.45), single device delivery (Group 1 vs. Group 2: 69.56% vs. 55%, P = 0.22), electrical performance at implant and at 12-month follow-up (Group 1 vs. Group 2: pacing threshold 0.48 ± 0.05 V/0.24 ms vs. 0.56 ± 0.25 V/0.24 ms, P = 0.70; impedance 640 ± 148.83 Ohm vs. 583.43 ± 99.7 Ohm, P = 0.27; and R wave amplitude 10.33 ± 2.88 mV vs. 12.62 ± 5.31 mV, P = 0.40). A non-apical site of implant was achievable in the majority of cases (72.3%) without differences among groups (78.26% vs. 70%; P = 0.42). CONCLUSION: Micra implant is an effective and safe procedure in patients still requiring a ventricular pacing after TLE, with similar electrical performance and outcome compared with naïve patients at long-term follow-up.

Leadless pacing in a patient with superior vena cava syndrome undergoing lead extraction and percutaneous angioplasty.

Superior vena cava (SVC) syndrome is an uncommon but serious complication associated with chronic transvenous implanted leads. In the recent past, open-heart surgery combining lead extraction and epicardial implant was usually performed to reduce syndrome recurrences. We describe the case of a 78-year-old man successfully treated by percutaneous lead extraction associated with venous balloon angioplasty and reimplantation of leadless pacemaker. .

Major predictors of fibrous adherences in transvenous implantable cardioverter-defibrillator lead extraction.

BACKGROUND: Percutaneous removal of implantable cardioverter-defibrillator (ICD) leads is a difficult procedure because of the consequence of massive fibrous tissue growth along the lead. OBJECTIVE: The purpose of this study was to describe the occurrence and location of fibrous adherences in ICD lead extraction and to identify potential predictors among patient and lead characteristics. METHODS: We studied 637 consecutive patients who underwent transvenous extraction of 678 ICD leads from 1997 to 2013. RESULTS: Procedural success rate was 99%, without major complications. Areas of adherence were found in the subclavian vein (78%), innominate vein (65%), superior vena cava (66%), and heart (73%). Dwell-time, passive fixation, and dual-coil lead design were independently associated with adherences. Dual-coil lead design was associated with adherences in the innominate vein and superior vena cava, whereas coil treatment (eg, expandable polytetrafluoroethylene-coated or medical adhesive back-filled strategies) prevented adherences. Passive fixation mechanism was associated with adherences in the heart. CONCLUSION: ICD leads, after long dwell-time, are affected by fibrous adherences uniformly distributed along the lead course. Lead features represent major predictors of the phenomenon. Careful lead selection is recommended at the time of implantation to prevent adherences. In addition, lead-related risk stratification is mandatory before a transvenous extraction procedure.

Large, single-center experience in transvenous coronary sinus lead extraction: procedural outcomes and predictors for mechanical dilatation.

BACKGROUND: The aim of this study was to evaluate procedural outcomes of coronary sinus (CS) lead extraction, focusing on predictors and need for mechanical dilatation (MD) in the event that manual traction (MT) is ineffective. METHODS: The study assessed results in 145 consecutive patients (age 69 ± 10 years; 121 men)--a total of 147 CS pacing leads--who underwent transvenous CS lead removal between January 2000 and March 2010. RESULTS: All leads but one (99%) (implantation time 29 ± 25 months) were successfully removed. MT was effective in 103 (70%), and MD was necessary in the remaining 44 (30%) procedures. In multivariate analyses, unipolar design (odds ratio [OR] 3.22, 95% confidence interval [CI] 1.43-7.7; P = 0.005) and noninfective indication (OR 4.8, 95% CI 1.8-13, P = 0.002) were independent predictors for MD (P < 0.0001), with a predictive trend for prior cardiac surgery (OR 2.2, 95% CI 0.98-5.26; P = 0.06). Five (3.4%) complex procedures required a transfemoral vein approach (TFA) or repeat procedure. No deaths occurred, and there was one major complication (0.7%), cardiac tamponade, after MT. No complication predictors were identified. CONCLUSIONS: CS leads were safely and effectively removed in nearly all patients, and 70% were removed with MT alone; 30% required MD. Preoperative predictors suggesting the need for MD or TFA were noninfective indication and unipolar lead design. Complications were rare, and there was no predictable pattern among MT or MD removal techniques.

Cardiac resynchronization therapy after coronary sinus lead extraction: feasibility and mid-term outcome of transvenous reimplantation in a tertiary referral centre.

AIMS: Few data are available on cardiac resynchronization therapy (CRT) after coronary sinus (CS) lead extraction. We aimed to evaluate the feasibility and mid-term outcome of transvenous CS lead reimplantation in a tertiary referral centre. METHODS AND RESULTS: We enrolled all patients who were referred to our hospital for CS lead removal from December 2000 through to May 2009 and were transvenously reimplanted with a CRT system before June 2009. One-year follow-up was performed to evaluate the incidence of infections, malfunctions, and mortality. We studied 113 consecutive patients undergoing successful CS lead extraction; 90 patients (75 male, mean age 69.2, range 35-84) underwent CS lead reimplantation (success rate: 95.6%; right-sided approach: 64.4%). In these patients, cardiac device infection was the usual indication for extraction (74.4%) and the subsequent reimplantation was performed after a median time of 3 days. The coronary sinus lead was usually positioned in the left ventricular (LV) postero-lateral region (62.2%); two procedures were required in two cases (2.2%). Balloon angioplasty was necessary for two patients (failure in one), whereas for the others we used a conventional implant technique. During follow-up, we observed four cases (4.4%) of local infection and six cases (6.7%) of system malfunction, requiring reintervention (two cases during the same hospitalization). One-year mortality was 5.5%. CONCLUSION: Left ventricular lead reimplantation is in our experience an effective and safe procedure, also in the case of right-sided approach. During follow-up, 1-year mortality was particularly low, whereas overall infection rate was higher than first implant procedures.

Radiofrequency catheter ablation of atrioventricular nodal reciprocating tachycardia using intracardiac echocardiography in pregnancy.

We describe a case report of a 32-year-old woman during the 10th week of pregnancy with symptomatic and recurrent atrioventricular nodal reciprocating tachycardia successfully treated by conventional radiofrequency ablation, under intracardiac echocardiography surveillance.

An arrhythmic storm: a potential complication on opening the umbrella for percutaneous closure of interatrial communications.

Interatrial communications (ICs) have been linked to paradoxic embolism, which may be prevented using both surgical and percutaneous interventions. The case of a 61-year-old woman with a history of transient cerebral ischemic attack who developed repetitive ventricular arrhythmias and an intermittent left branch bundle block immediately after percutaneous closure of an IC is described. Transthoracic echocardiography showed that the device had migrated into the left ventricular outflow tract, and the patient consequently underwent emergency cardiac surgery to retrieve the device and repair the IC. In conclusion, percutaneous transcatheter closure of ICs is more rapid and less invasive compared with surgery, but nevertheless may be associated with significant short-term morbidity.

Usefulness of mechanical transvenous dilation and location of areas of adherence in patients undergoing coronary sinus lead extraction.

AIMS: Few data have been currently reported on the outcome of coronary sinus (CS) lead removal, particularly using mechanical dilation (MD). We aimed to evaluate feasibility, safety, and effectiveness of CS lead extraction, focusing on MD usefulness, in the event that lead traction (LT) was ineffective. METHODS AND RESULTS: We studied 37 consecutive patients (30 males, mean age 68.1, range 52-80), who underwent left ventricle (LV) pacing lead removal; the indication for extraction was local infection in 16 patients (43.3%), sepsis in 11 patients (29.7%), and lead malfunction in 10 patients (27%). The procedure was first attempted by LT, followed, if unsuccessful, by MD using polypropylene sheaths. All CS leads (time from implant 19.5 +/- 16.5, range 2-84 months) were successfully removed; LT was effective (LT group) in 27 patients (73%) and ineffective in 10 patients (27%), for whom MD was necessary (MD group). There were no major complications. The areas of adherence were in the CS in only one patient. No differences were noted in the data analysed between LT and MD groups; in particular, time from implant was similar in the two groups (MD vs. LT group: 17 +/- 8.9 vs. 20.4 +/- 18.6 months; P = ns). CONCLUSION: Our study suggests that CS leads, after medium-term implantation, can be effectively and safely removed using MD with polypropylene sheaths, in the case of unsuccessful LT. No pre-operative elements predictive of LT failure could be identified. Areas of adherence were rarely located in the CS or its tributaries.

Severe aortic stenosis and myocardial function: diagnostic and prognostic usefulness of ultrasonic integrated backscatter analysis.

BACKGROUND: The aim of this study was to assess the myocardial reflectivity pattern in severe aortic valve stenosis through the use of integrated backscatter (IBS) analysis. Patients with aortic stenosis (AS) were carefully selected in the Department of Cardiology. METHODS AND RESULTS: Thirty-five subjects (AS: valve orifice < or =1 cm2; 12 female; mean age, 71.8+/-6.2 years) and 25 healthy subjects were studied. All subjects of the study had conventional 2D-Doppler echocardiography and IBS. Backscatter signal was sampled at the septum and posterior wall levels. Patients with AS were divided into 2 groups: 16 patients with initial signs of congestive heart failure and a depressed left ventricular systolic function (DSF) (ejection fraction [EF] range, 35% to 50%) and 19 asymptomatic patients with normal left ventricular systolic function (NSF) (EF >50%). Myocardial echo intensity (pericardium related) was significantly higher at the septum and posterior wall levels in DSF than in NSF and in control subjects. IBS variation, as an expression of variation of the signal, appeared to be significantly lower in AS with DSF than in NSF and in control subjects, at both the septum and posterior wall levels. Patients with DSF underwent aortic valve replacement, and, during surgical intervention, a septal myocardial biopsy was made for evaluation of myocardium/fibrosis ratio. Abnormally increased echo intensity was detected in left ventricular pressure overload by severe aortic stenosis and correlated with increase of myocardial collagen content (operating biopsy). CONCLUSIONS: One year after aortic valve replacement, we observed a significant reduction of left ventricular mass, and, only if pericardial indexed IBS value (reduction of interstitial fibrosis) decreased, it was possible to observe an improvement of EF and of IBS variation.

Interventricular hydatid cyst with atrioventricular block: a case report.

Hydatid cyst in the heart is rare, occurring in about 3% of human echinococcosis. A 21-year-old woman was admitted to hospital with a third degree atrioventricular block. Echocardiography showed a cystic mass with a diameter of 2.5 cm within the interventricular septum. Serologic testing for Echinococcus was clearly positive, and hence cardiac surgery was planned. Sterilization of the cystic cavity was achieved by injecting formaldehyde solution in the cavity before cystectomy. Definitive pacemaker implantation was necessary before discharge. Cardiac hydatid cysts constitute an indication for surgery which is necessary to prevent potentially lethal complications such as cystic rupture with embolic phenomena and anaphylactic shock.