Novel SCN5A gene mutation in a patient affected by multifocal ectopic premature Purkinje-related contractions syndrome.

We report the case of a 36-year-old woman who presented to the emergency department complaining of palpitations and asthenia. Investigations showed frequent ventricular ectopy and severe left ventricular ejection fraction impairment. She was diagnosed with a peculiar condition defined multifocal ectopic premature Purkinje-related contractions syndrome, which in some cases can be associated with a dilated cardiomyopathy phenotype. Genetic testing showed a novel mutation in the SCN5A gene (c.673C > G). In the context of acute left ventricular dysfunction in a young patient, we discuss the clinical presentation of this rare condition and its clinical management, as well as its genetic substrate.

Predictors of adverse cardiac events of coronary myocardial bridging diagnosed with computed tomography angiography.

AIMS: Myocardial bridging (MB) is a frequent congenital anomaly of the epicardial coronary arteries commonly considered a benign condition. However, in some cases a complex interplay between anatomical, clinical and physiology factors may lead to adverse events, including sudden cardiac death. Coronary CT angiography (CCTA) emerged as the gold standard noninvasive imaging technique for the evaluation of MB. Aim of the study was to evaluate MB prevalence and anatomical features in a large population of patients who underwent CCTA for suspected CAD and to identify potential anatomical and clinical predictors of adverse cardiac events at long-term follow-up. METHODS AND RESULTS: Two-hundred and six patients (mean age 60.3 ± 11.8 years, 128 male) with MB diagnosed at CCTA were considered. A long MB was defined as ≥25 mm of overlying myocardium, whereas a deep MB as ≥2 mm of overlying myocardium. The study endpoint was the sum of the following adverse events: cardiac death, bridge-related acute coronary syndrome, hospitalization for angina or bridge-related ventricular arrhythmias and MB surgical treatment. Of the 206 patients enrolled in the study, 9 were lost to follow-up, whereas 197 (95.6%) had complete follow-up (mean 7.01 ± 3.0 years) and formed the analytic population. Nineteen bridge-related events occurred in 18 patients (acute coronary syndrome in 7, MB surgical treatment in 2 and hospitalization for bridge-related events in 10). Typical angina at the time of diagnosis and long MB resulted as significant independent predictors of adverse outcome. CONCLUSIONS: Typical angina and MB length ≥ 25 mm were independent predictors of cardiac events.

Prevalence and prognosis of structural heart disease among athletes with negative T waves and normal transthoracic echocardiography.

INTRODUCTION: The aim of the present study was to evaluate the prevalence and prognosis of structural heart disease (SHD) among competitive athletes with negative T waves without pathological findings at transthoracic echocardiogram. METHODS: From a prospective register of 450 athletes consecutively evaluated during a second-level cardiological examination, we retrospectively identified all subjects with the following inclusion criteria: (1) not previously known cardiovascular disease; (2) negative T waves in leads other than V1-V2; (3) normal transthoracic echocardiogram. Patients underwent cardiac MRI and CT. The primary endpoint was the diagnosis of definite SHD after multimodality imaging evaluation. A follow-up was collected for a combined end-point of sudden death, resuscitated sudden cardiac death and hospitalization for any cardiovascular causes. RESULTS: A total of 55 competitive athletes were finally enrolled (50 males, 90%) with a mean age of 27.5 ± 14.1 years. Among the population enrolled 16 (29.1%) athletes had a final diagnosis of SHD. At multivariate analysis, only deep negative T waves remained statistically significant [OR (95% CI) 7.81 (1.24-49.08), p = 0.0285]. Contemporary identification of deep negative T waves and complex arrhythmias in the same patients appeared to have an incremental diagnostic value. No events were collected at 49.3 ± 12.3 months of follow-up. CONCLUSIONS: In a cohort of athletes with negative T waves at ECG, cardiac MRI (and selected use of cardiac CT) enabled the identification of 16 (29.1%) subjects with SHD despite normal transthoracic echocardiography. Deep negative T waves and complex ventricular arrhythmias were the only clinical characteristic associated with SHD diagnosis.

Pulsed-field ablation of pulmonary vein and left atrial posterior wall combined with left atrial appendage occlusion as single procedure.

Pulmonary vein isolation and left atrial posterior wall ablation using the Farapulse system, followed by left atrial appendage occlusion, have been achieved as single combined procedure to treat long-standing persistent atrial fibrillation in a patient at high hemorrhagic risk.

Anomalous origin of left circumflex artery from the right sinus of Valsalva: Clinical outcomes in a consecutive series of master athletes.

BACKGROUND: Aim of the study was to collect and describe a case series of consecutive master athletes in whom an anomalous origin of left circumflex artery (LCx) from the right sinus of Valsalva (ALCx) was detected at a clinically indicated coronary computed tomography angiography CCTA) to establish a focused clinical management and counseling about sport activity in those subjects. METHODS: We analyzed a prospective registry of subjects referred to a clinically indicated CCTA. Information about the clinical status was obtained by previous clinical records and clinical evaluation at time of image acquisition; follow-up allowed to record symptoms, outcomes and downstream testing. RESULTS: The study population consisted in 14 subjects, of which one competitive athlete and 13 recreational master athletes. Mean age was of 67.2 ± 10.6 years (71% of male); follow-up lasted 6.4 ± 2.6 years. The major high-risk anatomy features (inter-arterial course, intramural segment, high take-off and slit-like ostium) were absent. None had abnormal ostial morphology and all had full retroaortic course; three subjects (21%) presented an acute take-off angle. Coronary artery disease (CAD) was present in 10 patients (71%). Major outcomes (cardiac hospitalization, death for all causes) recorded were not related to the anomalous LCx. Symptoms were most related to atherosclerotic CAD in different vessels whereas two subjects without CAD exhibited cardiac symptoms, without hospitalization. CONCLUSIONS: Our study suggests that the diagnosis of ALCx, being usually associated to low-risk anatomical characteristics, could be considered a benign finding, with scarce or no implications for physically active individuals neither for recreational athletes.

Ventricular arrhythmias in athletes: Role of a comprehensive diagnostic workup.

BACKGROUND: Ventricular arrhythmias (VAs) represent a critical issue with regard to sports eligibility assessment in athletes. The ideal diagnostic evaluation of competitive and leisure-time athletes with complex VAs has not been clearly defined. OBJECTIVE: The purpose of this study was to assess the clinical implications of invasive electrophysiological assessments and endomyocardial biopsy (EMB) among athletes with VAs. METHODS: We evaluated 227 consecutive athletes who presented to our institutions after being disqualified from participating in sports because of VAs. After noninvasive tests, electrophysiological study (EPS), electroanatomic mapping (EAM), and EAM- or cardiac magnetic resonance imaging-guided EMB was performed, following a prespecified protocol. Sports eligibility status was redefined at 6-month follow-up. RESULTS: From our sample, 188 athletes (82.8%) underwent EAM and EPS, and 42 (15.2%) underwent EMB. A diagnosis of heart disease could be formulated in 30% of the study population (67/227; 95% confidence interval [CI] 0.24-0.36) after noninvasive tests; in 37% (83/227; 95% CI 31%-43%) after EPS and EAM; and in 45% (102/227; 95% CI 39%-51%) after EMB. In the subset of athletes undergoing EMB, invasive diagnostic workup allowed diagnostic reclassification of half of the athletes (n = 21 [50%]). Reclassification was particularly common among subjects without definitive findings after noninvasive evaluation (n = 23; 87% reclassified). History of syncope, abnormal echocardiogram, presence of late gadolinium enhancement, and abnormal EAM were linked to sports ineligibility at 6-month follow-up. CONCLUSION: A comprehensive invasive workup provided additional diagnostic elements and could improve the sports eligibility assessment of athletes presenting with VAs. The extensive invasive evaluation presented could be especially helpful when noninvasive tests show unclear findings.

Sudden Cardiac Death in Athletes: From the Basics to the Practical Work-Up.

Sudden cardiac death in athletes is a relatively rare event, but due to the increasing number of individuals practicing high-performance sports, in absolute terms, it has become an important issue to be addressed. Since etiologies are many and the occurrence is rare, tracing the ideal preparticipation screening program is challenging. So far, as screening tools, a comprehensive clinical evaluation and a simple 12-lead electrocardiogram (ECG) seem to be the most cost-effective strategy. Recent technological advances came to significantly help as second-line investigation tools, especially the cardiac magnetic resonance, which allows for a more detailed ventricular evaluation, cardiac tissue characterization, and eliminates the poor acoustic window problem. This article aims to review all aspects related to sudden cardiac death in athletes, beginning with definitions and epidemiology, passing through etiology and clinical characteristics, then finishing with a discussion about the best ambulatory investigational approach.

Cryoballoon atrial fibrillation ablation: Single-center safety and efficacy data using a novel cryoballoon technology compared to a historical balloon platform.

INTRODUCTION: Catheter ablation is superior to drugs regarding atrial fibrillation (AF) recurrence, symptoms improvement, and mortality reduction in heart failure. POLARx™ is a novel cryoballoon, with technical improvements seeking to improve outcomes. So far, its clinical evidence is restricted to a case report. METHODS: To compare the POLARx™ cryoballoon procedural safety and efficacy to the already established Arctic Front Advance PRO™ (AFAP) in a single-center cohort study, consecutive patients undergoing AF cryoablation with the POLARx™ were enrolled. Data were prospectively gathered. POLARx™ patients were compared with a historical cohort of patients submitted to AF cryoablation with the AFAP. RESULTS: Seventy patients were analyzed, 20 in POLARx™, and 50 in the AFAP group. They all underwent first-time pulmonary vein isolation, 77% were male, 94% had paroxysmal AF, median age was 62.5 years, median CHA2 DS2 -VASc 1, left-atrium size 34 ml/m², and 65% were receiving anticoagulation. The primary end-point, all pulmonary veins isolation, was 100% in both groups. The complication rate was similar (0% POLARx™ vs. 5.7% AFAP, p = .39). The median total procedural time was longer in the POLARx™ group (90 min vs. 60 min, p < .001), but the overall time-to-isolation (TTI; 44.8 s vs. 39 s, p = .253) and ablation time (15 min vs. 13.7 min, p = .122) was similar between POLARx™ and AFAP groups, respectively. Despite equal TTI, the POLARx™ had a lower minimal temperature reached (-57°C vs -47°C, p < .001). CONCLUSION: The novel POLARx™ cryoballoon had similar efficacy and safety compared with the AFAP. It was also associated with longer procedural times, similar TTI, and lower minimum temperature reached.

Use of a multi-electrode radiofrequency balloon catheter to achieve pulmonary vein isolation in patients with paroxysmal atrial fibrillation: 12-Month outcomes of the RADIANCE study.

BACKGROUND: The RADIANCE first-in-man study evaluated acute (3-month) safety and design concept in terms of utility of a new multi-electrode radiofrequency (RF) balloon catheter (HELIOSTAR, Biosense Webster) to achieve pulmonary vein isolation (PVI). After study conclusion, a subset of patients was followed up to 12 months. METHODS: Patients with drug refractory paroxysmal atrial fibrillation were enrolled. Neurological assessment, cardiac and cerebral magnetic resonance imagings were performed pre and post procedure. Ablation was delivered at 15 Watts to each PV for 60 seconds (electrodes adjacent to the posterior wall limited to 20 seconds). Adenosine or isoproterenol was administered to confirm PVI. Esophageal endoscopy was performed 48 hours post procedure. Patients were clinically followed up for 12 months. RESULTS: Thirty-nine patients underwent catheter ablation from four centers. Mean age was 60.7 ± 10.0 years with 23 (57.5%) being male. Confirmation of PVI was performed in all PVs treated (152/152). Confirmation of isolation after one delivery was performed solely on 137 of 152 PVs of which 79.6% (109/137) achieved isolation with a single delivery of RF energy. Acute PV reconnection was seen in 4.6% (7/150) of PVs. Freedom from documented atrial arrhythmia at 12 months in those followed up was 86.4% (32/37). A total of 75.7% (28/37) of patients were free from atrial arrhythmia and off antiarrhythmic medications. CONCLUSION: The HELIOSTAR RF balloon catheter allows for rapid and safe PVI with majority of PVs only requiring one application.

Novel risk calculator performance in athletes with arrhythmogenic right ventricular cardiomyopathy.

BACKGROUND: Disease progression and ventricular arrhythmias (VAs) in arrhythmogenic right ventricular cardiomyopathy (ARVC) are correlated with physical exercise, and clinical detraining and avoidance of competitive sport practice are suggested for ARVC patients. An algorithm assessing primary arrhythmic risk in ARVC patients was recently developed by Cadrin-Tourigny et al. Data regarding its transferability to athletes are lacking. OBJECTIVE: The purpose of this study was to assess the reliability of the Cadrin-Tourigny risk prediction algorithm in a cohort of athletes with ARVC and to describe the impact of clinical detraining on disease progression. METHODS: All athletes undergoing clinical detraining after ARVC diagnosis at our institution were enrolled. Baseline and follow-up clinical characteristics and data on VA events occurring during follow-up were collected. The Cadrin-Tourigny algorithm was used to calculate the a priori predicted VA risk, which was compared with the observed outcomes. RESULTS: Twenty-five athletes (age 36.1 ± 14.0 years; 80% male) with definite ARVC who were undergoing clinical detraining were enrolled. Over median (interquartile range) follow-up of 5.3 (3.2-6.6) years, a reduction in premature ventricular complex (PVC) burden (P = .001) was assessed, and 10 VA events (40%) were recorded. The a priori algorithm-predicted risk seemed to fit with the observed cohort arrhythmic risk [mean observed-predicted risk difference over 5 years -0.85% (interquartile range -4.8% to +3.1%); P = .85]. At 1-year follow-up, 11 patients (44%) had an improved stress ECG response, and no significant changes in right ventricular ejection fraction were observed. CONCLUSION: Clinical detraining is associated with PVC burden reduction in athletes with ARVC. The novel risk prediction algorithm does not seem to require any correction for its application to ARVC athletes.

Lesion index: a novel guide in the path of successful pulmonary vein isolation.

PURPOSE: Previous studies indicate force time integral (FTI) as a radiofrequency (RF) lesion quality marker, while not considering power supply. Tacticath™ Quartz catheter provides Lesion index (LSI), a lesion quality marker derived by contact force (CF), power supply, and RF time combined. Our aim is to assess LSI and FTI correlation and a LSI-related cutoff of atrial fibrillation (AF) recurrences 12 months after pulmonary vein isolation (PVI). METHODS: We retrospectively enrolled 37 patients who underwent RF ablation using Tacticath™ Quartz catheter. AF recurrence rate was evaluated 3, 6, and 12 months after PVI procedure. RESULTS: AF recurrence was detected in 32% of patients. FTI mean value was significantly lower in left superior pulmonary vein (LSPV: 256 ± 86 gs vs 329 ± 117 gs, p = 0.05) and right inferior pulmonary vein (RIPV: 253 ± 128 gs vs 394 ± 123 gs p = 0.006) in patients with AF recurrences; no significant differences were found in right superior pulmonary vein (RSPV) and left inferior pulmonary vein (LIPV). LSI instead was significantly higher for all veins in patients without AF recurrences: LSPV (5.2 ± 0.7 vs 4.6 ± 0.8, p = 0.03), LIPV (5.0 ± 0.8 vs 4.5 ± 0.6, p = 0.04), RSPV (5.5 ± 0.6 vs 5.1 ± 0.6, p = 0.05), and RIPV (5.5 ± 0.7 vs 4.7 ± 0.8, p = 0.006). Receiver operator characteristic curve suggests 5.3 as LSI overall cutoff value predicting freedom from disease at 1-year follow-up. CONCLUSIONS: Our preliminary data suggest that a LSI mean value higher than 5.3 can be considered a good predictor of AF freedom at 1-year follow-up.

X-Ray Exposure in Cardiac Electrophysiology: A Retrospective Analysis in 8150 Patients Over 7 Years of Activity in a Modern, Large-Volume Laboratory.

BACKGROUND: Only a few studies have systematically evaluated fluoroscopy data of electrophysiological and device implantation procedures. Aims of this study were to quantify ionizing radiation exposure for electrophysiological/device implantation procedures in a large series of patients and to analyze the x-ray exposure trend over years and radiation exposure in patients undergoing atrial fibrillation ablation considering different technical aspects. METHODS AND RESULTS: We performed a retrospective analysis of all electrophysiological/device implantation procedures performed during the past 7 years in a modern, large-volume laboratory. We reported complete fluoroscopy data on 8150 electrophysiological/device implantation procedures (6095 electrophysiological and 2055 device implantation procedures); for each type of procedure, effective dose and lifetime attributable risk of cancer incidence and mortality were calculated. Over the 7-year period, we observed a significant trend reduction in fluoroscopy time, dose area product, and effective dose for all electrophysiological procedures (P<0.001) and a not statistically significant trend reduction for device implantation procedures. Analyzing 2416 atrial fibrillation ablations, we observed a significant variability of fluoroscopy time, dose area product and effective dose among 7 different experienced operators (P<0.0001) and a significant reduction of fluoroscopy use over time (P<0.0001) for all of them. Considering atrial fibrillation ablation techniques, fluoroscopy time was not different (P = 0.74) for radiofrequency catheter ablation in comparison with cryoablation, though cryoablation was still associated with higher dose area product and effective dose values (P<0.001). CONCLUSIONS: Electrophysiological procedures involve a nonnegligible x-ray use, leading to an increased risk of malignancy. Awareness of radiation-related risk, together with technological advances, can successfully optimize fluoroscopy use.

Collateral findings during computed tomography scan for atrial fibrillation ablation: Let's take a look around.

The growing number of atrial fibrillation catheter ablation procedures warranted the development of advanced cardiac mapping techniques, such as image integration between electroanatomical map and cardiac computed tomography. While scanning the chest before catheter ablation, it is frequent to detect cardiac and extracardiac collateral findings. Most collateral findings are promptly recognized as benign and do not require further attention. However, sometimes clinically relevant collateral findings are detected, which often warrant extra diagnostic examinations or even invasive procedure, and sometimes need to be followed-up over time. Even though reporting and further investigating collateral findings has not shown a clear survival benefit, almost all the working groups providing data on collateral findings reported some collateral findings eventually coming out to be malignancies, sometimes at an early stage. Therefore, there is currently no clear agreement about the right strategy to be followed.

Near zerO fluoroscopic exPosure during catheter ablAtion of supRavenTricular arrhYthmias: the NO-PARTY multicentre randomized trial.

AIMS: Aim of this study was to compare a minimally fluoroscopic radiofrequency catheter ablation with conventional fluoroscopy-guided ablation for supraventricular tachycardias (SVTs) in terms of ionizing radiation exposure for patient and operator and to estimate patients' lifetime attributable risks associated with such exposure. METHODS AND RESULTS: We performed a prospective, multicentre, randomized controlled trial in six electrophysiology (EP) laboratories in Italy. A total of 262 patients undergoing EP studies for SVT were randomized to perform a minimally fluoroscopic approach (MFA) procedure with the EnSiteTMNavXTM navigation system or a conventional approach (ConvA) procedure. The MFA was associated with a significant reduction in patients' radiation dose (0 mSv, iqr 0-0.08 vs. 8.87 mSv, iqr 3.67-22.01; P < 0.00001), total fluoroscopy time (0 s, iqr 0-12 vs. 859 s, iqr 545-1346; P < 0.00001), and operator radiation dose (1.55 vs. 25.33 µS per procedure; P < 0.001). In the MFA group, X-ray was not used at all in 72% (96/134) of cases. The acute success and complication rates were not different between the two groups (P = ns). The reduction in patients' exposure shows a 96% reduction in the estimated risks of cancer incidence and mortality and an important reduction in estimated years of life lost and years of life affected. Based on economic considerations, the benefits of MFA for patients and professionals are likely to justify its additional costs. CONCLUSION: This is the first multicentre randomized trial showing that a MFA in the ablation of SVTs dramatically reduces patients' exposure, risks of cancer incidence and mortality, and years of life affected and lost, keeping safety and efficacy. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01132274.

Electrical storm: A clinical and electrophysiological overview.

Electrical storm (ES) is a clinical condition characterized by three or more ventricular arrhythmia episodes leading to appropriate implantable cardioverter-defibrillator (ICD) therapies in a 24 h period. Mostly, arrhythmias responsible of ES are multiple morphologies of monomorphic ventricular tachycardia (VT), but polymorphic VT and ventricular fibrillation can also result in ES. Clinical presentation is very dramatic in most cases, strictly related to the cardiac disease that may worsen electrical and hemodynamic decompensation. Therefore ES management is challenging in the majority of cases and a high mortality is the rule both in the acute and in the long-term phases. Different underlying cardiomyopathies provide significant clues into the mechanism of ES, which can arise in the setting of structural arrhythmogenic cardiomyopathies or rarely in patients with inherited arrhythmic syndrome, impacting on pharmacological treatment, on ICD programming, and on the opportunity to apply strategies of catheter ablation. This latter has become a pivotal form of treatment due to its high efficacy in modifying the arrhythmogenic substrate and in achieving rhythm stability, aiming at reducing recurrences of ventricular arrhythmia and at improving overall survival. In this review, the most relevant epidemiological and clinical aspects of ES, with regard to the acute and long-term follow-up implications, were evaluated, focusing on these novel therapeutic strategies of treatment.

Usefulness of intracardiac echocardiography during pulmonary vein isolation with the novel multipolar irrigated ablation catheter (nMARQ™).

BACKGROUND: Previous studies reported the usefulness of an irrigated circular radiofrequency ablation catheter (nMARQ(TM), Biosense Webster) for pulmonary vein isolation (PVI). We evaluated the role of intracardiac echocardiography (ICE) to optimize the manipulation of nMARQ(TM) catheter. METHODS: Thirty-seven patients (pts), (mean age 55 ± 12 years; 28 males) were enrolled to perform PVI. All pts underwent PVI with the nMARQ(TM) catheter. In 20 pts (group 1), we utilized ICE to guide nMARQ(TM) catheter positioning at the PV ostia; in the other 17 pts (group 2), nMARQ(TM) catheter was positioned at the PV ostia guided by fluoroscopy and TissueConnect(TM) technology. RESULTS: Radiofrequency (RF) applications were significantly lower in group 1 compared to group 2 [left PVs: 6 (range 3 to 12) in group 1 and 12 (range 5 to 16) in group 2 (p < 0.001); right PVs: 7 (range 4 to 14) in group 1 and 10 (range 5 to 16) in group 2 (p = 0.04)]; similarly regarding the time of RF delivery [left PVs: 318 ± 194 s in group 1 vs. 542 ± 104 s in group 2 (p < 0.001); right PVs: 410 ± 270 s in group 1 vs. 550 ± 156 s in group 2 (p = 0.05)]. Fluoroscopy time (23 ± 9 min vs. 28 ± 5 min; p = 0.05), procedural time (83 ± 23 min vs. 160 ± 42 min; p < 0.001), and radiation dose (109 ± 20 Gy/cm(2) vs. 127 ± 29 Gy/cm(2); p = 0.04) were significantly lower in group 1 compared to group 2. CONCLUSION: ICE might be a useful tool to guide nMARQ(TM) catheter position in the left atrium during atrial fibrillation (AF) ablation procedures.

Feasibility of combined unipolar and bipolar voltage maps to improve sensitivity of endomyocardial biopsy.

BACKGROUND: Endomyocardial biopsy (EMB) has a low sensitivity. Electroanatomic voltage mapping (EVM) is effective in guiding EMB thanks to its ability in identifying and locating low-voltage regions. The analysis of unipolar EVM can correlate with epicardial pathological involvement. We evaluated the unipolar EVM in EMB areas to determine whether it can increase EMB sensitivity in diagnosing epicardial diseases. METHODS AND RESULTS: We performed endocardial bipolar EVM-guided EMBs in 29 patients and we analyzed unipolar EVM at withdrawal sites. Eighty myocardial samples were collected (mean, 2.8±0.9; median, 3 fragments per patient) and 60 were suitable for histological analysis. Ten specimens (17%) were collected from an area with discordant normal bipolar/low-voltage unipolar EVM and they were diagnostic or suggestive for arrhythmogenic right ventricular dysplasia/cardiomyopathy in 6 patients, for myocarditis and sarcoidosis in 1 patient each. Six samples (10%) were collected from an area with discordant low-voltage bipolar/normal unipolar EVM and they showed nonspecific features. The sensitivity of unipolar EVMs for a diagnostic biopsy finding EMB was significantly higher compared with bipolar EVMs analyzed according to samples (P<0.01) and patients (P=0.008). The specificity of unipolar EMB was better than bipolar EMB when analyzed for all samples (P=0.0014) but the difference did not reach statistical significance when analyzed by patient (P=0.083). The diagnostic yield was 63.3% for the bipolar and 83.3% for the unipolar EVM. CONCLUSIONS: These findings suggest that use of a combined bipolar/unipolar map may be able to improve the diagnostic yield of endomyocardial ventricular biopsy.

Idiopathic Ventricular Tachycardia: Transcatheter Ablation or Antiarrhythmic Drugs?

INTRODUCTION: Ventricular tachycardia or frequent premature ventricular contractions (PVCs) can occur in the absence of any detectable structural heart disease. In this clinical setting, these arrhythmias are termed idiopathic. Usually, they carry a benign prognosis and any potential ablative intervention is carried out if patients are highly symptomatic or, more importantly, if frequent ventricular arrhythmias can lead to ventricular dysfunction. METHODS: In this paper, different forms of idiopathic ventricular tachycardia are reviewed. Outflow tract ventricular tachycardia from the right ventricle is the most frequent form of the so-called idiopathic ventricular tachycardia. Other forms of idiopathic ventricular arrhythmias include ventricular tachycardia/PVCs arising from tricuspid annulus, from the mitral annulus, inter-fascicular ventricular tachycardia and papillary muscle ventricular tachycardia. When interventional treatment is deemed necessary, detailed mapping ( earliest activation during VT/PVC, pace mapping ) is crucial as to identify the successful ablation site. Catheter ablation more than antiarrhythmic drug treatment is usually highly effective in eliminating idiopathic ventricular arrhythmias and providing prevention of recurrence. CONCLUSIONS: Idiopathic VTs are not considered life-threatening arrhythmias and, prevention of recurrences is often achieved by means of catheter ablation that provides an improvement of quality of life. The overall acute success rate of catheter ablation is about 85-90% with a long-term prevention of arrhythmia recurrence of about 75-80%. It is advisable that the procedure is carried out by electrophysiologists with expertise in VT catheter ablation and extensive knowledge of cardiac anatomy as to ensure a high success rate and reduce the likelihood of major complications.

Electrical storm in systemic sclerosis: Inside the electroanatomic substrate.

We report the case of a 63-year-old woman affected by a severe form of systemic scleroderma with pulmonary involvement (interstitial fibrosis diagnosed by biopsy and moderate pulmonary hypertension) and cardiac involvement (paroxysmal atrial fibrillation, right atrial flutter treated by catheter ablation, ventricular tachyarrhythmias, previous dual chamber implantable cardioverter defibrillator implant). Because of recurrent electrical storms refractory to iv antiarrhythmic drugs the patient was referred to our institution to undergo catheter ablation. During electrophysiological procedure a 3D shell of cardiac anatomy was created with intracardiac echocardiography pointing out a significant right ventricular dilatation with a complex aneurysmal lesion characterized by thin walls and irregular multiple trabeculae. A substrate-guided strategy of catheter ablation was accomplished leading to a complete electrical isolation of the aneurism and to the abolishment of all abnormal electrical activities. The use of advanced strategies of imaging together with electroanatomical mapping added important information to the complex arrhythmogenic substrate and improved efficacy and safety.