The prevalence of left and right bundle branch block morphology ventricular tachycardia amongst patients with arrhythmogenic cardiomyopathy and sustained ventricular tachycardia: insights from the European Survey on Arrhythmogenic Cardiomyopathy.

AIMS: In arrhythmogenic cardiomyopathy (ACM), sustained ventricular tachycardia (VT) typically displays a left bundle branch block (LBBB) morphology while a right bundle branch block (RBBB) morphology is rare. The present study assesses the VT morphology in ACM patients with sustained VT and their clinical and genetic characteristics. METHODS AND RESULTS: Twenty-six centres from 11 European countries provided information on 954 ACM patients who had ≥1 episode of sustained VT spontaneously documented during patients' clinical course. Arrhythmogenic cardiomyopathy was defined according to the 2010 Task Force Criteria, and VT morphology according to the QRS pattern in V1. Overall, 882 (92.5%) patients displayed LBBB-VT alone and 72 (7.5%) RBBB-VT [alone in 42 (4.4%) or in combination with LBBB-VT in 30 (3.1%)]. Male sex prevalence was 79.3%, 88.1%, and 56.7% in the LBBB-VT, RBBB-VT, and LBBB + RBBB-VT groups, respectively (P = 0.007). First RBBB-VT occurred 5 years after the first LBBB-VT (46.5 ± 14.4 vs 41.1 ± 15.8 years, P = 0.011). An implanted cardioverter-defibrillator was more frequently implanted in the RBBB-VT (92.9%) and the LBBB + RBBB-VT groups (90%) than in the LBBB-VT group (68.1%) (P < 0.001). Mutations in PKP2 predominated in the LBBB-VT (65.2%) and the LBBB + RBBB-VT (41.7%) groups while DSP mutations predominated in the RBBB-VT group (45.5%). By multivariable analysis, female sex was associated with LBBB + RBBB-VT (P = 0.011) while DSP mutations were associated with RBBB-VT (P < 0.001). After a median follow-up of 103 (51-185) months, death occurred in 106 (11.1%) patients with no intergroup difference (P = 0.176). CONCLUSION: RBBB-VT accounts for a significant proportion of sustained VTs in ACM. Sex and type of pathogenic mutations were associated with VT type, female sex with LBBB + RBBB-VT, and DSP mutation with RBBB-VT.

Prognostic Value of Nonischemic Ringlike Left Ventricular Scar in Patients With Apparently Idiopathic Nonsustained Ventricular Arrhythmias.

BACKGROUND: Left ventricular (LV) scar on late gadolinium enhancement (LGE) cardiac magnetic resonance has been correlated with life-threatening arrhythmic events in patients with apparently idiopathic ventricular arrhythmias (VAs). We investigated the prognostic significance of a specific LV-LGE phenotype characterized by a ringlike pattern of fibrosis. METHODS: A total of 686 patients with apparently idiopathic nonsustained VA underwent contrast-enhanced cardiac magnetic resonance. A ringlike pattern of LV scar was defined as LV subepicardial/midmyocardial LGE involving at least 3 contiguous segments in the same short-axis slice. The end point of the study was time to the composite outcome of all-cause death, resuscitated cardiac arrest because of ventricular fibrillation or hemodynamically unstable ventricular tachycardia and appropriate implantable cardioverter defibrillator therapy. RESULTS: A total of 28 patients (4%) had a ringlike pattern of scar (group A), 78 (11%) had a non-ringlike pattern (group B), and 580 (85%) had normal cardiac magnetic resonance with no LGE (group C). Group A patients were younger compared with groups B and C (median age, 40 vs 52 vs 45 years; P<0.01), more frequently men (96% vs 82% vs 55%; P<0.01), with a higher prevalence of family history of sudden cardiac death or cardiomyopathy (39% vs 14% vs 6%; P<0.01) and more frequent history of unexplained syncope (18% vs 9% vs 3%; P<0.01). All patients in group A showed VA with a right bundle-branch block morphology versus 69% in group B and 21% in group C (P<0.01). Multifocal VAs were observed in 46% of group A patients compared with 26% of group B and 4% of group C (P<0.01). After a median follow-up of 61 months (range, 34-84 months), the composite outcome occurred in 14 patients (50.0%) in group A versus 15 (19.0%) in group B and 2 (0.3%) in group C (P<0.01). After multivariable adjustment, the presence of LGE with ringlike pattern remained independently associated with increased risk of the composite end point (hazard ratio, 68.98 [95% CI, 14.67-324.39], P<0.01). CONCLUSIONS: In patients with apparently idiopathic nonsustained VA, nonischemic LV scar with a ringlike pattern is associated with malignant arrhythmic events.

Electrocardiographic Repolarization Abnormalities and Electroanatomic Substrate in Arrhythmogenic Right Ventricular Cardiomyopathy.

BACKGROUND: Repolarization abnormalities in arrhythmogenic right ventricular (RV) cardiomyopathy and their relationship to ventricular tachycardia substrate are incompletely understood. METHODS AND RESULTS: In 40 patients (29 men, mean age 38 years) with arrhythmogenic RV cardiomyopathy, we compared the extent and location of abnormal T (NegT) waves ≥1 mm in depth (n=32) and downsloping elevated ST segment (n=13), in ≥2 adjacent leads, to area and location of endocardial bipolar (<1.5 mV) and unipolar (<5.5 mV) and epicardial bipolar (<1.0 mV) voltage abnormalities. Abnormal unipolar RV endocardial area of 33.4±19.3% was present in 8 patients without NegT waves. Patients with NegT waves extending beyond lead V3 (n=20) had larger low bipolar (31.4±18.9% versus 16.5±14.6%; P=0.008) and unipolar endocardial areas (66.0±19.6% versus 47.4±25.1%; P=0.013) and larger epicardial low bipolar area (56.0±19.3% versus 40.1±24.9%; P=0.030) compared with those with NegT waves limited to leads V1 through V3 (n=20). ECG location of NegT waves regionalized to location of substrate. Patients with downsloping elevated ST segment, all localized to leads V1 and V2, had more unipolar endocardial abnormalities (71.8±18.1% versus 49.4±23.5%; P=0.005) involving outflow and mid-RV, compared with patients without downsloping elevated ST segment. CONCLUSIONS: In arrhythmogenic RV cardiomyopathy, abnormal electroanatomic mapping areas are proportional to extent of T-wave inversion on 12-lead ECG. Marked voltage abnormalities can exist without repolarization change. Downsloping elevated ST-segment pattern in V1 and V2 occurs with more unipolar endocardial voltage abnormality, consistent with more advanced transmural disease.

A Balanced View of Efficacy and Safety of Aspirin in Cardiovascular Diseases.

This review highlights practical aspects related to aspirin therapy in cardiovascular diseases, specifically, the benefits and hazards in different clinical settings. Aspirin reduces one fourth of all major cardiovascular events but also increases major gastrointestinal bleeds by about half. As with other cardiovascular prevention strategies, the absolute benefit of aspirin is linearly related to the cardiovascular risk of the patient. The risk-benefit of aspirin can vary substantially in different settings: in secondary prevention, the benefits usually outweigh the excess of major bleeding complications. In primary prevention, it is not unusual that the number of vascular events avoided equals the number of major bleeds induced by aspirin. Finally, there is a growing body of evidence suggesting that aspirin may interfere with the early stages of cancer, metastasis and mortality. For all these reasons, in this article new developments in the field directed towards individualized risk assessment strategies are also discussed.

Pulmonary vein isolation in patients with Brugada syndrome and atrial fibrillation: a 2-year follow-up.

AIMS: Pharmacological treatment of atrial fibrillation (AF) in the setting of Brugada syndrome (BS) might be challenging as many antiarrhythmic drugs (AADs) with sodium channel blocking properties might expose the patients to the development of ventricular arrhythmias. Moreover, patients with BS and implantable cardioverter-defibrillator (ICD) might experience inappropriate shocks because of AF with rapid ventricular response. The role of pulmonary vein isolation (PVI) in patients with BS and recurrent episodes of AF has not been established yet. In this study, we analysed the outcome of PVI using radiofrequency energy or cryoballoon (CB) ablation at 2 years follow-up. METHODS AND RESULTS: Consecutive patients with BS having undergone PVI for drug-resistant paroxysmal AF were eligible for this study. Nine patients (three males; mean age: 52 ± 26 years) were included. Six patients (67%) had an ICD implanted of whom three had inappropriate shocks because of rapid AF. At a mean 22.1 ± 6.4 months follow-up, six patients (67%) were free of AF without AADs. None of the three patients who had experienced inappropriate ICD interventions for AF had further ICD shocks after ablation. CONCLUSION: In our study PVI can be an effective and safe procedure to treat patients with BS and recurrent episodes of paroxysmal AF.

Initial experience of three-minute freeze cycles using the second-generation cryoballoon ablation: acute and short-term procedural outcomes.

BACKGROUND: The second-generation cryoballoon (CB-A) (Arctic Front Advance, Cryocath, Medtronic, MN, USA) might significantly improve procedural outcome with respect to the first-generation balloon. These technological improvements might also question the current recommendation of the need a 4-min freeze to achieve durable pulmonary vein isolation (PVI). OBJECTIVE: The main aim of the study was to analyze the procedural efficacy of a 3-min freeze-thaw cycles with the CB-A balloon in the terms of rates of acute PVI and 6-month outcome. METHODS: Patients having undergone CB-A for PAF or early persistent AF, with 3-min freeze-thaw cycles were consecutively included in our analysis. Acute procedural success was measured in terms of the rate of PVI. Short-term follow-up was evaluated by the means of 24-h Holters and clinical examinations at regular intervals. RESULTS: Fifty-two consecutive patients (35 male (67 %); mean age, 59.8 ± 10.5) were included. Mean procedure and fluoroscopy times were 96 ± 15 and 13.2 ± 8.3 min, respectively. Mean time from groin puncture to catheter extraction was 60.4 ± 20 min. After a mean of 1.5 freeze cycles per vein of 3 min in duration, all 208 (100 %) PVs could be isolated with the CB-A. A total 192 (91 %) veins were isolated during the first freeze. At a mean of 5.7-month follow-up, 82 % of patients were free of AF. CONCLUSION: CB-A is effective in producing PVI by using 3-min-duration freeze cycles. After a mean of 1.5 freeze per vein, freedom from AF was achieved in 82 % of patients at 6-month follow-up.

Cryoballoon ablation as index procedure for paroxysmal atrial fibrillation: long-term results from a single center early experience.

AIMS: Cryoballoon ablation (CRAB) as a modality for pulmonary vein isolation (PVI) is increasingly being accepted. We aim to study the long-term durability of CRAB in atrial fibrillation. METHODS: The first 51 consecutive patients with documented paroxysmal atrial fibrillation(PAF) who underwent CRAB at our institute were considered. Forty patients formed the study group. Successful PVI was achieved in all the patients. Patients were evaluated with Holter ECG recordings at 1, 3, 6 and 12 months and subsequent follow-up was biannual and based on the clinical status and physician discretion whether symptoms occurred. For the study purpose, a baseline ECG, a 24-h Holter and clinical evaluation were performed in all patients at final follow-up. RESULTS: A large 28-mm cryoballoon (CB) was used in 38 patients (95%), and the small 23-mm CB in the remaining two individuals (2%). The freedom from atrial fibrillation off-antiarrhythmic drug treatment (AAD) after a single procedure at a mean follow-up of 36.6 ±â€Š4 months was 57.5% (23/40). Transient right phrenic nerve palsy was the most common complication. CONCLUSION: Single balloon size CRAB provides a durable atrial fibrillation-free-AAD-free survival in drug-resistant PAF patients over long-term follow-up with a success rate of 57.5% with a single procedure.

Safe single-dose administration of propofol in patients with established Brugada syndrome: a retrospective database analysis.

BACKGROUND: Propofol is an anesthetic drug with a very attractive pharmacokinetic profile, which makes it the induction agent of choice, especially in day-case surgery. Data on its potential proarrhythmic effects in patients with Brugada syndrome (BS) patients are still lacking. The aim of our study was to investigate whether a single dose of propofol triggered any adverse events in consecutive high-risk patients with BS. METHODS: All consecutive patients with BS having undergone an implantable cardiac defibrillator implantation under general anesthesia were eligible for this study. The anesthetic chart of each patient was reviewed, and the occurrence of malignant arrhythmic events as well as the need for defibrillation during induction and maintenance of anesthesia was investigated. Further monitoring of the patient comprised five-lead electrocardiogram (ECG), pulse oxymetry, and continuous carbon dioxide monitoring through side sampling from the ventilator tubes. Anesthesia was induced with propofol and sufentanyl. Injection of propofol occurred in a single-shot bolus-as often performed by most anesthetists-over a few seconds. Anesthesia was maintained with volatile anesthetics (sevoflurane or desflurane) in an oxygen-air mixture. RESULTS: From 1996 to 2011, 57 high-risk patients with BS (35 males; mean age: 43 ± 16 years) underwent an automated implantable cardioverter defibrillator implantation at our center using propofol as induction drug of general anesthesia. Three patients had a history of spontaneous type I ECG, three had aborted sudden death, and 51 had a history of recurrent or unexplained syncope. The induction dose ranged between 0.8 mg/kg and 5.0 mg/kg (2.2 ± 0.7 mg/kg). Only one case received propofol to maintain anesthesia. The surgical procedure involved an anesthetic period of 75 ± 25 minutes. No patient developed a malignant rhythm during induction and maintenance of anesthesia. All patients were then safely discharged from the postanesthetic care unit after 1 hour. No adverse events were noticed during the recovery phase. In our study, administration of a single-dose propofol in patients with BS was safe. Nevertheless, extreme caution is still recommended when conducting general anesthesia in patients with BS, especially if BS patients are sedated with propofol for longer periods.

Impact of transseptal puncture site on acute and mid-term outcomes during cryoballoon ablation: a comparison between anterior, medial and posterior transatrial access.

BACKGROUND: Cryoballoon ablation (CBA) (Arctic Front, Medtronic, USA) has proven very effective in achieving pulmonary vein isolation (PVI). Different transseptal (TS) puncture sites might influence CBA procedure. The aim of the present study was to analyze the influence of different TS puncture sites (anterior, medial and posterior) on the acute and midterm outcomes of CBA in a series of patients undergoing PVI for drug resistant AF. METHODS AND RESULTS: A total 103 patients (78 males, mean age: 57 ± 13 years) formed the study group. Transseptal punctures were performed in the anterior, medial and posterior portion of the FO in 41 (39.8%), 35 (34%) and 27 (26.2%) patients respectively. We found no statistical significant difference between the various sites of TS puncture in 1) the grade of PV occlusion (p = ns), the rate of PV isolation (p = ns), freedom from AF at a mean 12 month follow-up (p = ns) and complication rates (p = ns). Mean grade of occlusion was slightly lower in the RIPV when puncturing in the posterior FO but did not reach statistical significance. Mean procedural and fluoroscopy times were significantly lower when using the inner lumen mapping catheter (ILMC) (Achieve, Medtronic, USA) than the circular mapping catheter (CMC) (Lasso, Biosense Webster, California, USA) (107.24 mn vs 97.74 (p ≤ 0.001) and 25.7 mn vs 19.2 mn (p ≤ 0.001)). CONCLUSION: Different sites of TS puncture on the horizontal axis of the FO (anterior, medial and posterior) did not influence grades of PV occlusion, rates of isolation, mid-term outcome and rates of complications during CB ablation.

Phrenic nerve paralysis during cryoballoon ablation for atrial fibrillation: a comparison between the first- and second-generation balloon.

BACKGROUND: Phrenic nerve palsy (PNP) is the most frequently observed complication during cryoballoon ablation (CB; Arctic Front, Medtronic, MN) occurring in roughly 7%-9% of the cases. The new second-generation cryoballoon ablation Arctic Front Advance (CB-A) (Arctic Front) has recently been launched in the market. OBJECTIVE: To evaluate the incidence of right PNP with the new CB-A in comparison with the first-generation balloon in a series of consecutive patients that underwent pulmonary vein isolation with this modality. METHODS: The study was designed as an observational study with a prospective follow-up. In total, 121 consecutive patients were included: 80 patients with the CB (group 1) and 41 with the CB-A (group 2). RESULTS: Mean procedural times, fluoroscopic times, and time to pulmonary vein isolation documented by real-time recordings were significantly lower in group 2 (P ≤ .05). The occurrence of PNP was significantly higher in group 2 (6.25% [5 of 80] in group 1 vs 19.5% [8 of 41] in group 2; P = .033). At 7 months, PNP persisted in 1 (2.5%) patient in the CB-A group. CONCLUSIONS: Right PNP seems to occur in a significantly larger number of patients with the second-generation CB-A. However, this complication is reversible in nearly all cases on short-term follow-up. More refined phrenic nerve monitoring during right-sided pulmonary vein ablation and less vigorous wedging maneuvers in the pulmonary vein ostia might significantly reduce the occurrence of this complication.

Repeat procedure using radiofrequency energy for recurrence of atrial fibrillation after initial cryoballoon ablation: a 2-year follow-up.

AIMS: The ideal energy source needed to perform 're-isolation' of the pulmonary veins (PVs) during a repeat procedure for recurrence of paroxysmal atrial fibrillation (AF) has not been established yet. In this study we analysed the outcome of repeat procedure using radiofrequency (RF) energy after initial cryoballoon (CB) ablation at 2-year follow-up. METHODS AND RESULTS: Consecutive patients having undergone PVs isolation as repeat procedure for recurrent AF after an initial CB ablation were eligible for this study. Twenty-nine patients (22 male 76%, mean age: 55 ± 17 years) were included. Mean time to repeat ablation was 12 ± 7 months. Recovered PV conduction could be documented in a mean 2.45 ± 0.7 veins in each patient. At mean 20.2 ± 10.7 months follow-up, a total of 16 patients (55%) were free of AF at without antiarrhythmic drugs (AADs). An adjunctive 31% was AF free with previously ineffective AADs. A major complication with no permanent clinical sequelae occurred only in one patient. CONCLUSION: Repeat RF ablation following CB in case of AF recurrence is effective and safe.

Verification of pulmonary vein isolation during single transseptal cryoballoon ablation: a comparison between the classical circular mapping catheter and the inner lumen mapping catheter.

AIMS: Cryoballoon ablation has proven very effective in achieving pulmonary vein isolation (PVI). The novel Achieve inner lumen mapping catheter designed to be used in conjunction with the cryoballoon, serves as both a guidewire and a mapping catheter. To our knowledge, this is the first study comparing the latter to verification of electrical isolation with the 'traditional' circular mapping catheter. METHODS AND RESULTS: We assigned 40 consecutive patients matched for age and left atrial diameter suffering of paroxysmal atrial fibrillation to cryoballoon PVI using either the circular mapping catheter or the Achieve as a mapping catheter. Duration of procedure as well as fluoroscopy times were significantly lower in the Achieve group than in the circular mapping catheter group (111 ± 14 min vs. 126 ± 13 min, P < 0.005 and 22 ± 5 min vs. 29 ± 4 min, P < 0.0001, respectively). There were no significant differences between both groups in terms of mean degree of occlusion, mean minimal temperatures, and PVI. Pulmonary vein isolation could be documented by real-time recordings in 55% of veins in the Achieve group with mean time to isolation of 65 ± 23 s. CONCLUSION: Cryoballoon ablation in conjunction with the novel Achieve is feasible, safe, and affords PVI in nearly all veins in similar proportions to the approach with the traditional guidewire. Furthermore, if compared to the procedure with the circular mapping catheter, cryoballoon ablation with the Achieve is significantly faster and associated to shorter fluoroscopy times.

Balancing the risk and benefits of low-dose aspirin in clinical practice.

Antiplatelet agents are widely used in primary and secondary prevention of cardiovascular events. The scientific evidence has provided strong support for the benefits of aspirin in decreasing the risk of cardiovascular events in a wide range of pathologies. The relatively rare occurrence of major bleeding complications should not be underestimated, mainly due to its high morbi-mortality. The assessment of both gastrointestinal risk and cardiovascular benefits of low-dose aspirin for any individual patient may be difficult in clinical practice. In this review, we summarize the evidence supporting the efficacy of aspirin and the risks of side effects due to hemorrhagic complications. This article proposes a unifying framework for application to help the clinician in the decision making process of individuals who have different risk of cardiovascular and bleeding events with different examples. Finally, new developments in the field directed towards individualized risk assessment strategies are described.

Pulmonary vein isolation during cryoballoon ablation using the novel Achieve inner lumen mapping catheter: a feasibility study.

AIMS: Cryoballoon (CB) ablation has proven very effective in achieving pulmonary vein isolation (PVI). The Achieve catheter (AC) is a novel inner lumen catheter designed to be used in conjunction with the CB, which serves the double purpose of a guidewire and a mapping catheter. We aimed to evaluate the feasibility of CB ablation in conjunction with the novel AC, in terms of PVI and safety in a series of patients affected by drug resistant paroxysmal atrial fibrillation (AF). METHODS AND RESULTS: Seventy patients (49 male) affected by paroxysmal AF were assigned to CB PVI using the AC as a mapping catheter. Patients underwent loop-Holter monitoring 1, 3 and 6 months after ablation. Isolation occurred in 98% of PVs with the CB-AC association without having switching to a regular guidewire. Pulmonary vein isolation could be documented by real-time (RT) recordings in 47% (132) of veins. Time to isolation was significantly longer in PVs exhibiting early left atrium-PV reconnection if compared with veins with sustained isolation (117 ± 25 s vs. 59 ± 25 s; P< 0,005). No serious complications occurred; four transient phrenic nerve palsies occurred all resolving completely before the end of the procedure. CONCLUSION: Cryoballoon ablation in conjunction with the novel AC is feasible, safe, and most importantly affords PVI in nearly all veins without having to switch to a regular guidewire. However, RT recordings could be documented in only 47% of pulmonary veins.