Sex-Related Differences in Ventricular Tachyarrhythmia Events in Patients With Implantable Cardioverter-Defibrillator and Prior Ventricular Tachyarrhythmias.

BACKGROUND: Data on the risk of ventricular tachycardia (VT), ventricular fibrillation (VF), and death by sex in patients with prior VT/VF are limited. OBJECTIVES: This study aimed to assess sex-related differences in implantable cardioverter-defibrillator (ICD)-treated VT/VF events and death in patients implanted for secondary prevention or primary prevention ICD indications who experienced VT/VF before enrollment in the RAID (Ranolazine Implantable Cardioverter-Defibrillator) trial. METHODS: Sex-related differences in the first and recurrent VT/VF requiring antitachycardia pacing or ICD shock and death were evaluated in 714 patients. RESULTS: There were 124 women (17%) and 590 men observed during a mean follow-up of 26.81 ± 14.52 months. Compared to men, women were at a significantly lower risk of VT/VF/death (HR: 0.67; P = 0.029), VT/VF (HR: 0.68; P = 0.049), VT/VF treated with antitachycardia pacing (HR: 0.59; P = 0.019), and VT/VF treated with ICD shock (HR: 0.54; P = 0.035). The risk of recurrent VT/VF was also significantly lower in women (HR: 0.35; P < 0.001). HR for death was similar to the other endpoints (HR: 0.61; P = 0.162). In comparison to men, women presented with faster VT rates (196 ± 32 beats/min vs 177 ± 30 beats/min, respectively; P = 0.002), and faster shock-requiring VT/VF rates (258 ± 56 beats/min vs 227 ± 57 beats/min, respectively; P = 0.30). There was a significant interaction for the risk of VT/VF by race (P = 0.013) with White women having significantly lower risk than White men (HR: 0.36; P < 0.001), whereas Black women had a similar risk to Black men (HR: 1.06; P = 0.851). CONCLUSIONS: Women with a history of prior VT/VF experienced a lower risk recurrent VT/VF requiring ICD therapy when compared to men. Black Women had a risk similar to men, whereas the lower risk for VT/VF in women was observed primarily in White women. (Ranolazine Implantable Cardioverter-Defibrillator Trial; NCT01215253).

Reduction in Ventricular Tachyarrhythmia Burden in Patients Enrolled in the RAID Trial.

BACKGROUND: The RAID (Ranolazine Implantable Cardioverter-Defibrillator) randomized placebo-controlled trial showed that ranolazine treatment was associated with reduction in recurrent ventricular tachycardia (VT) requiring appropriate implantable cardioverter-defibrillator (ICD) therapy. OBJECTIVES: This study aimed to identify groups of patients in whom ranolazine treatment would result in the highest reduction of ventricular tachyarrhythmia (VTA) burden. METHODS: Andersen-Gill analyses were performed to identify variables associated with risk for VTA burden among 1,012 patients enrolled in RAID. The primary endpoint was VTA burden defined as VTA episodes requiring appropriate treatment. RESULTS: Multivariate analysis identified 7 factors associated with increased VTA burden: history of VTA, age ≥65 years, New York Heart Association functional class ≥III, QRS complex (≥130 ms), low ejection fraction (<30%), atrial fibrillation (AF), and concomitant antiarrhythmic drug (AAD) therapy. The effect of ranolazine on VTA burden was seen among patients without concomitant AAD therapy (HR [HR]: 0.68; 95% CI: 0.55-0.84; P < 0.001), whereas no effect was seen among those who are concomitantly treated with other AADs (HR: 1.33; 95% CI: 0.90-1.96; P = 0.16); P = 0.003 for interaction. In patients with cardiac resynchronization therapy (CRT) ICDs, ranolazine treatment was associated with a 36% risk reduction for VTA recurrence (HR: 0.64; 95% CI: 0.47-0.86; P < 0.001), whereas among patients with ICDs without CRT no significant effect was noted (HR: 0.94; 95% CI: 0.74-1.18; P = 0.57); P = 0.047 for interaction. CONCLUSIONS: In patients with high risk for VTA, ranolazine is effective in reducing VTA burden, with significantly greater effect in CRT-treated patients, those without AF, and those not treated with concomitant AADs. In patients already on AADs or those with AF, the addition of ranolazine did not affect VTA burden. (Ranolazine Implantable Cardioverter-Defibrillator Trial [RAID]; NCT01215253).

Junctional AV ablation in patients with atrial fibrillation undergoing cardiac resynchronization therapy (JAVA-CRT): results of a multicenter randomized clinical trial pilot program.

INTRODUCTION: Cardiac resynchronization therapy (CRT) improves outcomes in sinus rhythm, but the data in atrial fibrillation (AF) is limited. Atrio-ventricular junctional ablation (AVJA) has been proposed as a remedy. The objective was to test if AVJA results in LV end-systolic volume (ESV) reduction ≥ 15% from baseline to 6 months. METHODS: The trial was a prospective multicenter randomized trial in 26 patients with permanent AF who were randomized 1:1 to CRT-D with or without AVJA. RESULTS: LVESV improved similarly by at least 15% in 5/10 (50%) in the CRT-D-only arm and in 6/12 (50%) in the AVJA + CRT-D arm (OR = 1.00 [0.14, 7.21], p = 1.00). In the CRT-D-only arm, the median 6-month improvement in LVEF was 9.2%, not different from the AVJA + CRT-D arm, 8.2%. When both groups were combined, a significant increase in LVEF was observed (25.4% at baseline vs 36.2% at 6 months, p = 0.002). NYHA class from baseline to 6 months for all patients combined improved 1 class in 15 of 24 (62.5%), whereas 9 remained in the same class and 0 degraded to a worse class. CONCLUSION: In patients with permanent AF, reduced LVEF, and broad QRS who were eligible for CRT, there was insufficient evidence that AVJA improved echocardiographic or clinical outcomes; the results should be interpreted in light of a smaller than planned sample size. CRT, however, seemed to be effective in the combined study cohort overall, suggesting that CRT can be reasonably deployed in patients with AF. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02946853.

Sinus node sparing novel hybrid approach for treatment of inappropriate sinus tachycardia/postural sinus tachycardia: multicenter experience.

BACKGROUND: The ideal treatment of inappropriate sinus tachycardia (IST) and postural orthostatic tachycardia syndrome (POTS) still needs to be defined. Medical treatments yield suboptimal results. Endocardial catheter ablation of the sinus node (SN) may risk phrenic nerve damage and open-heart surgery may be accompanied by unjustified invasive risks. METHODS: We describe our first multicenter experience of 255 consecutive patients (235 females, 25.94 ± 3.84 years) having undergone a novel SN sparing hybrid thoracoscopic ablation for drug-resistant IST (n = 204, 80%) or POTS (n = 51, 20%). As previously described, the SN was identified with 3D mapping. Surgery was performed through three 5-mm ports from the right side. A minimally invasive approach with a bipolar radiofrequency clamp was used to ablate targeted areas while sparing the SN region. The targeted areas included isolation of the superior and the inferior caval veins, and a crista terminalis line was made. All lines were interconnected. RESULTS: Normal sinus rhythm (SR) was restored in all patients at the end of the procedure. All patients discontinued medication during the follow-up. After a blanking period of 6 months, all patients presented stable SR. At a mean of 4.07 ± 1.8 years, normal SN reduction and chronotropic response to exercise were present. In the 51 patients initially diagnosed with POTS, no syncope occurred. During follow-up, pericarditis was the most common complication (121 patients: 47%), with complete resolution in all cases. Pneumothorax was observed in 5 patients (1.9%), only 3 (1.1%) required surgical drainage. Five patients (1.9%) required a dual-chamber pacemaker due to sinus arrest > 5 s. CONCLUSIONS: Preliminary results of this multicenter experience with a novel SN sparing hybrid ablation of IST/POTS, using surgical thoracoscopic video-assisted epicardial ablation combined with simultaneous endocardial 3D mapping may prove to be an efficient and safe therapeutic option in patients with symptomatic drug-resistant IST and POTS. Importantly, in our study, all patients had a complete resolution of the symptoms and restored normal SN activity.

Robotic application of a novel dual-energy device for left atrial ablation: intraoperative and early postoperative results.

OBJECTIVE: Recent trials show that in patients with atrial fibrillation (AF), pulmonary vein isolation performed with bipolar surgical ablation clamps using small bilateral thoracotomies is more effective than pulmonary vein isolation using standard catheter ablation. This improved efficacy comes with higher invasiveness including difficulty in execution and potentially more acute complications. Monopolar "loop" devices overcome these drawbacks but at the potential cost of decreased efficacy. Technology that has bipolar effectiveness but with improved access and safety profiles, capable of being deployed endoscopically on a beating heart, would be desirable. We evaluated an ablation system that may have all of these characteristics. METHODS: Between May 2012 and May 2013, 30 patients were treated surgically for AF using a right-sided endoscopic approach with robotic assistance. In each patient, a "box" ablation lesion set was created around all pulmonary veins with a new linear suction-applied dual-mode (monopolar and bipolar) radiofrequency (RF) ablation device that was looped around the pulmonary veins. Temperature-controlled RF was applied for 60 seconds, with a set temperature of 70°C, first in the bipolar mode and then in a separate RF ablation for 60 seconds at 70°C in the monopolar mode. Acute effectiveness of the procedure was assessed using conduction block testing and by attempting to induce sustained AF with rapid atrial pacing. The left atrial appendage (LAA) was occluded in all patients with multiple ENDOLOOP snares using a left video-assisted thoracoscopic surgery approach under transesophageal echocardiography guidance, after which the tip of the LAA was incised to empty the LAA of blood. All patients were seen clinically at 30, 90, and 180 days with routine electrocardiography monitoring: at 6 months, 24-hour Holter monitoring was performed. RESULTS: Acute conduction block was achieved in 93% the of patients, and sustained AF could not be induced by rapid atrial pacing after the surgical ablation procedure in 90% of the patients. At 3- and 6-month follow-up, 88% and 81% of the patients, respectively, were in sinus rhythm. Of 16 the patients seen at 12-month follow-up, 14 (88%) were in sinus rhythm with 44% still on antiarrhythmic medications. CONCLUSIONS: The newly introduced bipolar/monopolar RF ablation device can be easily positioned using a right endoscopic approach. Robotic assistance enables effective fat removal for accurate and easy placement of the device around the pulmonary veins. With the use of this approach, the device is safe and effective in electrically isolating the pulmonary veins.

Anatomic substrate, procedural results, and clinical outcome of ultrasound-guided left atrial-pulmonary vein disconnection for treatment of atrial fibrillation.

This report summarizes the efficacy, safety, and feasibility of intracardiac ultrasound (ICUS) and local electrographic-guided pulmonary vein (PV)-left atrial disconnection, including the isolation of common PV trunks accomplished in 170 consecutive patients with atrial fibrillation (AF). A left common PV was found in 43% of patients with AF. During a follow-up of 549 +/- 330 days after ablation, the AF-free survival rate was 80% and comparable in paroxysmal and persistent AF. PV stenosis was detected in only 1 asymptomatic patient, who required no intervention.

Increased incidence of life-threatening ventricular arrhythmias in implantable defibrillator patients after the World Trade Center attack.

OBJECTIVES: This study was designed to evaluate whether the destruction of the World Trade Center (WTC) on September 11, 2001 (9/11), led to an increased frequency of ventricular arrhythmias among patients fitted with an implantable cardioverter-defibrillator (ICD). BACKGROUND: The WTC attack induced psychological distress. Because ICDs store all serious arrhythmias for months, the attack provided a unique opportunity to compare pre- and post-9/11 frequencies of potentially lethal arrhythmias among ICD patients. METHODS: Two hundred consecutive ICD patients who presented for regularly scheduled follow-up to six affiliated clinics were recruited into this observational study. The electrograms stored in the ICDs for the three months before 9/11 and 13 months thereafter were scrutinized in a blinded manner (relative to date) for all ventricular tachyarrhythmias (tachycardia or fibrillation) triggering ICD therapy. RESULTS: The frequency of tachyarrhythmias increased significantly for the 30 days post-9/11 (p = 0.004) relative to all other months between May 2001 and October 2002. In the 30 days post-9/11, 16 patients (8%) demonstrated tachyarrhythmias, compared with only seven (3.5%) in the preceding 30 days, representing a 2.3-fold increase in risk (95% confidence interval 1.1 to 4.9; p = 0.03). The first arrhythmic event did not occur for three days following 9/11, with events accumulating in a progressive non-clustered pattern. CONCLUSIONS: Ventricular arrhythmias increased by more than twofold among ICD patients following the WTC attack. The delay in onset and the non-clustered pattern of these events differ sharply from effects following other disasters, suggesting that subacute stress may have served to promote this arrhythmogenesis.

Robotically assisted left ventricular epicardial lead implantation for biventricular pacing.

OBJECTIVES: Ventricular resynchronization might be achieved in a minimally invasive fashion using a robotically assisted, direct left ventricular (LV) epicardial approach. BACKGROUND: Approximately 10% of patients undergoing biventricular pacemaker insertion have a failure of coronary sinus (CS) cannulation. Rescue therapy for these patients currently is limited to standard open surgical techniques. METHODS: Ten patients with congestive heart failure (New York Heart Association class 3.4 +/- 0.5) and a widened QRS complex (184 +/- 31 ms) underwent robotic LV lead placement after failed CS cannulation. Mean patient age was 71 +/- 12 years, LV ejection fraction (EF) was 12 +/- 6%, and LV end-diastolic diameter was 7.1 +/- 1.3 cm. Three patients had previous cardiac surgery, and five patients had a prior device implanted. RESULTS: Nineteen epicardial leads were successfully placed on the posterobasal surface of the LV. Intraoperative lead threshold was 1.0 +/- 0.5 V at 0.5 ms, R-wave was 18.6 +/- 8.6 mV, and impedance was 1,143 +/- 261 ohms at 0.5 V. Complications included an intraoperative LV injury and a postoperative pneumonia. Improvements in exercise tolerance (8 of 10 patients), EF (19 +/- 13%, p = 0.04), and QRS duration (152 +/- 21 ms, p = 0.006) have been noted at three to six months follow-up. Lead thresholds have remained unchanged (2.1 +/- 1.4 V at 0.5 ms, p = NS), and a significant drop in impedance (310 +/- 59 ohms, p < 0.001) has been measured. CONCLUSIONS: Robotic LV lead placement is an effective and novel technique which can be used for ventricular resynchronization therapy in patients with no other minimally invasive options for biventricular pacing.