Usefulness of Genetic Testing in Sudden Cardiac Arrest Survivors With or Without Previous Clinical Evidence of Heart Disease.

Genetic testing in survivors of sudden cardiac arrest (SCA) with a suspicious cardiac phenotype is considered clinically useful, whereas its value in the absence of phenotype is disputed. We aimed to evaluate the clinical utility of genetic testing in survivors of SCA with or without cardiac phenotype. Sixty unrelated SCA survivors (median age: 34 [interquartile range 20 to 43] years, 82% male) without coronary artery disease were included: 24 (40%) with detectable cardiac phenotype (Ph(+)SCA) after the SCA event and 36 (60%) with no clear cardiac phenotype (Ph(-)SCA). The targeted exome sequencing was performed using the TruSight-One Sequencing Panel (Illumina). Variants in 185 clinically relevant cardiac genes with minor allele frequency <1% were analyzed. A total of 32 pathogenic or likely pathogenic variants were found in 27 (45%) patients: 17 (71%) in the Ph(+)SCA group and 10 (28%) in the Ph(-)SCA group. Sixteen (67%) Ph(+)SCA patients hosted mutations congruent with the suspected phenotype, in which 12 (50%) were cardiomyopathies and 4 (17%) channelopathies. In Ph(-)SCA cases, 6 (17%) carried a mutation in cardiac ion channel genes that could explain the event. The additional 4 (11%) mutations in this group, could not explain the phenotype and require additional studies. In conclusion, cardiac genetic testing was positive in nearly 2/3 patients of the Ph(+)SCA group and in 1/6 of the Ph(-)SCA group. The test was useful in both groups to identify or confirm an inherited heart disease, with an important impact on the patient care and first-degree relatives at risk.

Safety of Uninterrupted Periprocedural Edoxaban Versus Phenprocoumon for Patients Who Underwent Left Atrial Catheter Ablation Procedures.

Data about the safety of edoxaban in patients who underwent left atrial (LA) radiofrequency (RF) ablation procedures are lacking. This study sought to compare the safety of uninterrupted edoxaban with uninterrupted phenprocoumon administration during LA RF ablation for atrial fibrillation and atrial tachycardia. In total, 231 patients (mean age 64 ± 11years, male 71%) who underwent LA RF ablation under continuous oral anticoagulation (OAC) with edoxaban or phenprocoumon were included in the study. Patients on uninterrupted edoxaban (60 mg or 30 mg/day for at least 4 weeks) were matched for gender, age and type of arrhythmia with 2 patients on uninterrupted phenprocoumon (international normalized ratio 2 to 3). We identified 77 consecutive patients on edoxaban and n = 154 patients on phenprocoumon. Heparin was administered periprocedurally to achieve an activated clotting time of 280 to 300 seconds. No protamine was administered periprocedurally. The primary end point was a composite of bleeding, thromboembolic events, and death. The primary end point was met in 9 patients in the edoxaban group and in 22 patients in the phenprocoumon group (p = 0.69). No patient in either group died or had a thromboembolic complication. No major bleeding complication was observed in the edoxaban group, whereas one was found in 1 patient in the phenprocoumon group (p ≥0.99). Minor bleeding complications occurred in 9 patients (12%) in the edoxaban group and in 21 patients (14%) in the phenprocoumon group (p = 0.84). Uninterrupted OAC with edoxaban appeared to be as safe as uninterrupted OAC with phenprocoumon in patients who underwent LA RF ablation procedures.

Catheter Ablation of Ventricular Arrhythmias using a Fluoroscopy Image Integration Module.

BACKGROUND: The impact of the CartoUnivu™ technology (Biosense Webster, Diamond Bar, CA, USA) on fluoroscopy exposure compared to a conventional approach using electroanatomical mapping (Carto 3™) was evaluated in patients undergoing radiofrequency ablation for ventricular tachyarrhythmias (VT). METHODS AND RESULTS: We prospectively evaluated 23 patients undergoing VT ablation using the CartoUnivu™ technology. The CartoUnivu™ Module integrates fluoroscopic images and cine loops into the electroanatomical mapping system. As a control group, 23 out of 88 VT patients (ablated using conventional fluoroscopy supplemented by electromagnetic mapping with the Carto 3™ System) were matched for age, gender, body surface area, operator, redo-procedure, presence of coronary artery disease, and left ventricular dysfunction using propensity score matching. A significant reduction in fluoroscopy exposure was observed in the CartoUnivu™ group when compared to the conventional group (10.57 ± 7.93 minutes vs 18.52 ± 11.24 minutes, P_= 0.008; 611 cGy/cm(2) vs 1650 cGy/cm(2) , P = 0.001). In multivariate analysis, the CartoUnivu™ module was an independent predictor of reduced fluoroscopy use. CONCLUSION: This is a report on the clinical application of the CartoUnivu system for VT ablation. CartoUnivu™ markedly reduced fluoroscopy time and dose compared to conventional fluoroscopy/electroanatomical mapping.

Recurrence of paroxysmal atrial fibrillation after pulmonary vein isolation: is repeat pulmonary vein isolation enough? A prospective, randomized trial.

AIMS: In patients with paroxysmal atrial fibrillation (pAF), pulmonary vein isolation (PVI) has become an accepted treatment option with single procedure success rates of 60-80%. A repeat ablation is performed in ∼30% of patients because of arrhythmia recurrence. The strategy for this repeat procedure is not defined. METHODS AND RESULTS: Patients with pAF recurrence after PVI were prospectively randomized and underwent a second ablation procedure with either PVI of all reconnected veins or PVI with an additional left atrial anterior line. Follow-up in our arrhythmia clinic was every 3 months up to 12 months including 7 day Holter monitoring. A total of 77 patients (mean age 63 ± 9 years, 69% males) were included in the analysis. A repeat PVI was performed in 41 patients, PVI + anterior line in 36 patients. After a follow-up of 12 months, 26 of 41 (63%) patients after repeat PVI and 18 of 36 (50%) patients with PVI + anterior line were in stable sinus rhythm off antiarrhythmic medication (P = 0.26). In most patients (12 of 15 patients with PVI and 14 of 18 patients with PVI + anterior line) with an arrhythmia recurrence after the second procedure, the recurring arrhythmia was paroxysmal AF. In 2 of 15 patients of the PVI group and in 4 of 18 patients of the PVI + anterior line group atypical flutter was the reoccurring arrhythmia (P = NS). CONCLUSION: In this prospective randomized trial, patients with a recurrence of paroxysmal AF had no better outcome after repeat PVI + one left atrial line compared with patients with repeat PVI only.

Pulmonary vein isolation using new technologies to improve ablation lesion formation: Initial results comparing enhanced catheter tip irrigation (Surround Flow(®)) with contact force measurement (Smarttouch(®)).

INTRODUCTION: Pulmonary vein reconnection after pulmonary vein isolation (PVI) is a significant problem in the treatment of paroxysmal atrial fibrillation (AF). We report about patients who underwent contact force (CF) guided PVI using CF catheter and compared them to patients with PVI using an ablation catheter with enhanced tip irrigation. METHODS: A total of 59 patients were included in the analysis. In 30 patients circumferential PVI was performed using the Thermocool Smarttouch(®) ablation catheter (ST) whereas in 29 patients circumferential PVI using the Thermocool Surround Flow SF(®) ablation catheter (SF) was performed. Patients were compared in regard to procedure time, fluoroscopy time/dose as well as RF-application duration and completeness of PVI. Adverse events (pericardial effusion, PV stenosis, stroke, death) were evaluated. The presence of sinus rhythm off antiarrhythmic medication was assessed during 6 months follow-up using multiple 7 day Holter-ECGs. RESULTS: In both groups, all PVs were isolated without serious adverse events. Procedure time was 2.15 ± 0.5 h (ST) vs. 2.37 ± 1.13 h (SF) (p = 0.19). Duration of RF-applications was 46.6 ± 18 min (ST) and 49.8 ± 19 min (SF) (p = 0.52). Fluoroscopy time was 25.2 ± 13 min (ST) vs. 29 ± 18 min (SF), fluoroscopy dose 2675.6 ± 1658 versus 3038.3 ± 1997 cGym(2) (p = 0.36 and 0.46 respectively). Sinus rhythm off antiarrhythmic medication validated with 7 day Holter ECGs was present in both groups in 72% of patients after 6 months of follow up. CONCLUSION: PVI using the new contact force catheter is safe and effective in patients with paroxysmal AF.

Comparison of safety of left atrial catheter ablation procedures for atrial arrhythmias under continuous anticoagulation with apixaban versus phenprocoumon.

Apixaban is increasingly used for stroke prevention in patients with atrial fibrillation. Data about the safety of left atrial radiofrequency ablation procedures under continuous apixaban therapy are lacking. We performed a matched-cohort study of patients undergoing left atrium ablation procedures for atrial fibrillation or left atrial flutter. For each patient on apixaban, 2 patients on phenprocoumon were matched by age, gender, and type of arrhythmia. The primary safety end point was a composite of bleeding, thromboembolic events, and death. We identified 105 consecutive patients (35 women; mean age 63 years) on apixaban and matched 210 phenprocoumon patients (70 women, mean age 64 years). The primary end point was met in 11 patients of the apixaban group and 26 patients of the phenprocoumon group (10.5% vs 12.3%, p = 0.71). Major bleeding complications occurred in 1 patient of the apixaban group and 1 patient of the phenprocoumon group (1% vs 0.5%, p >0.99). Minor bleeding complications were observed in 10 patients of the apixaban group and 25 patients of the phenprocoumon group (9.5% vs 11.9%, p = 0.61). No patient in either group experienced a thromboembolic event and no patient died. In patients on apixaban, no clinical variable was predictive for bleeding complications. Left atrial ablation procedures under continuous oral anticoagulation with apixaban are feasible and as safe as under continuous oral anticoagulation with phenprocoumon.

Safety of continuous periprocedural rivaroxaban for patients undergoing left atrial catheter ablation procedures.

BACKGROUND: This study aimed to evaluate the safety of continuous periprocedural rivaroxaban administration during left atrial radiofrequency ablation (RFA) in comparison with uninterrupted oral vitamin K antagonist administration. Data about the use of rivaroxaban in the setting of left atrial RFA procedures are lacking. METHODS AND RESULTS: The study cohort included 544 patients (mean age, 63±10 years) who underwent left atrial RFA procedures between February 2012 and May 2013. All patients (n=272) receiving uninterrupted periprocedural rivaroxaban 15 or 20 mg/d before the procedure (rivaroxaban) were matched by age, sex, and type of rhythm disorder with an equal number of patients managed with uninterrupted vitamin K antagonist phenprocoumon (international normalized ratio, 2-3). During RFA, heparin was given intravenously to maintain an activated clotting time at 270 to 300 s. The safety end point was a composite of bleeding, thromboembolic events, and death. There were no thromboembolic complications and no deaths in either group. The prevalence of major bleeding complications was similar in both groups (1 tamponade in RivG and 1 groin hematoma requiring transfusion in phenprocoumon). Minor bleeding complications occurred equally in both groups (20 of 272; 7% in the rivaroxaban versus 33 of 272, 12% in the phenprocoumon; P=0.08). In multivariable analyses, female sex was associated with a greater risk of complications (odds ratio, 1.96; 95% confidence interval, 1.10-3.49). CONCLUSIONS: In patients undergoing left atrial RFA, continuous periprocedural rivaroxaban use seems to be as safe as uninterrupted periprocedural phenprocoumon administration.

A prospective randomized study comparing isolation of the arrhythmogenic vein versus all veins in paroxysmal atrial fibrillation.

BACKGROUND: Ablation procedures in patients with paroxysmal atrial fibrillation (PAF) includes isolation of all pulmonary veins (PVs). We hypothesized that an approach using an algorithm to detect arrhythmogenic PVs (aPVs) might lead to shorter procedure duration (PD) and fewer proarrhythmic effects (PE). HYPOTHESIS: Isolation of the aPVs only leads to a reduced PD, reduced PEs, and fewer adverse events, with a success rate comparable to the standard all-PV approach. METHODS: In this prospective trial, 207 patients with PAF were randomized to undergo isolation of the aPV (AG group, n = 105) or isolation of all PVs (VG group, n = 102). The aPV was identified by atrial fibrillation (AF) induction, focal discharge, or short local PV decremental conduction during PV pacing. Patients were followed with repetitive 7-day Holter electrocardiograms (ECGs) after 3, 6, and 12 months in our arrhythmia clinic. RESULTS: In 97% of patients, at least 1 aPV was identified (mean, 2.1). PD did not differ significantly (152.3 ± 57.1 minutes vs 162 ± 68 minutes, P = 0.27) between the groups, but the number of radiofrequency (RF) applications and fluoroscopy time (FT) and dose were significantly lower in the AG group than in the VG group. The occurrence of PE (new-onset atrial tachycardia) and adverse events (AE) did not differ between the 2 groups (P = 0.1). Sinus rhythm off antiarrhythmic medication (documented on 7-day Holter ECGs) 12 months after a single procedure was achieved in 53% in the AG group and 59% in the VG group (P = 0.51). CONCLUSIONS: Isolation of the aPVs detected by a straightforward algorithm leads to similar success rates compared to a standard all-PV approach with regard to PD, AE, or PE and is associated with less RF and a shorter FT.

Importance of sinus rhythm as endpoint of persistent atrial fibrillation ablation.

BACKGROUND: The endpoint of persistent atrial fibrillation (AF) ablation is still a matter of debate. The purpose of this study was to evaluate if sinus rhythm (SR) as endpoint of persistent AF ablation has a better long-term outcome compared to atrial tachycardia (AT) or AF at the end of the procedure. METHODS AND RESULTS: Between 2008 and 2011, 191 consecutive patients undergoing de novo catheter ablation for symptomatic persistent and long-standing persistent AF using a sequential ablation approach (including pulmonary vein isolation, ablation of complex fractionated electrograms and linear lesions) were included in the study. According to the result at the end of ablation procedure, patients were classified into 3 groups: patients with termination of AF into SR (Group 1, n = 62), patients with AT undergoing cardioversion (CV) (Group 2, n = 47), or patients with AF undergoing CV (Group 3, n = 82). The primary endpoint was freedom from any atrial tachyarrhythmia off antiarrhythmic drugs at 12 months. At 12 months, estimated proportions of patients free from any arrhythmia recurrence were 42% for Group 1, 13% for Group 2, and 25% for Group 3 (P = 0.002). In a Cox regression analysis only termination into SR was associated with a lower risk of arrhythmia recurrence (HR: 0.62; P = 0.04). CONCLUSION: If SR is achieved as endpoint of persistent and long-standing persistent AF ablation using a sequential ablation approach it is associated with the highest long-term single procedure success rate compared to AT or AF at the end of the procedure.

Continuous respiratory monitoring for sleep apnea screening by ambulatory hemodynamic monitor.

AIM: To validate the sleep-disordered breathing components of a portable electrocardiography and hemodynamic monitor to be used for sleep apnea screening. METHODS: Sleep-disordered breathing (SDB) is associated with cardiovascular disease. Patients with existing cardiovascular disease may have unrecognized SDB or may develop SDB while under the care of a cardiologist. A screening device for SDB, easy to use and appealing to cardiologists, would assist in referral of appropriate patients for full polysomnography (PSG). A cardiac and respiratory monitor (CPAM) was attached to patients undergoing PSG and an apnea/hypopnea index (AHI) generated. The CPAM device produced respiration rate, snoring rate, individual apnea/hypopnea events and an SDB severity score (SDBSS). In addition to AHI, an expert over-reader annotated individual breaths, snores and SDB breathing events to which the automated algorithms were compared. RESULTS: The test set consisted of data from 85 patients (age: 50.5 ± 12.4 years). Of these, 57 had a positive PSG defined as AHI ≥ 5.0 (mean: 30.0 ± 29.8, negative group mean: 1.5 ± 1.2). The sensitivity and specificity of the SDBSS compared to AHI was 57.9% and 89.3%, respectively. The correlation of snoring rate by CPAM compared to the expert over-reader was r = 0.58 (mean error: 1.52 snores/min), while the automated respiration rate had a correlation of r = 0.90 (mean error: 0.70 breaths/min). CONCLUSION: This performance assessment shows that CPAM can be a useful portable monitor for screening and follow-up of subjects for SDB.

Assessment of systolic and diastolic function in asymptomatic subjects using ambulatory monitoring with acoustic cardiography.

BACKGROUND: Adequately recording diastolic heart sounds and systolic time intervals over longer periods is difficult. Thus, information on the circadian variation of these parameters in an ambulatory population is lacking. Moreover, age-related changes in the prevalence of diastolic heart sounds and measurements of systolic time intervals in an asymptomatic population have not been studied in continuous recordings. HYPOTHESIS: Diastolic heart sounds and systolic time intervals will have age and circadian variations that reflect known changes in cardiac function due to aging and circadian rhythms. METHODS: We studied 128 asymptomatic subjects wearing an ambulatory monitor with acoustic cardiography. The recording spanned a mean duration of 14 hours, including sleep. Data were analyzed for the presence of third (S3) and fourth (S4) heart sounds and for systolic time intervals. RESULTS: In these asymptomatic subjects, S3 was significantly more prevalent in those age <40 years than in those age >40 years, and significantly more pronounced during sleep in the younger group. Also, S4 was significantly more prevalent in those age >40 years and significantly more pronounced during sleep in those age >40 years. In contrast, time intervals reflecting systolic function showed less circadian variation and less worsening with age. CONCLUSIONS: The nocturnal increase of S4 in the elderly reflects diastolic impairment-likely a result of changes in diastolic filling patterns with increasing age. An S3 after the age of 40 is a relatively uncommon finding and therefore should be a specific sign of cardiac disease. Continuous monitoring of diastolic heart sounds and systolic time intervals is possible using acoustic cardiography.

Prevalence of preexcitation in a young population of male Swiss conscripts.

BACKGROUND: Sudden cardiac death can be the first clinical presentation of asymptomatic ventricular preexcitation. Recent data about prevalence of preexcitation in the electrocardiograms (ECG) of the general population are scarce. OBJECTIVE: The aim of the present study was to analyze the prevalence of preexcitation in a contemporary population of young conscripts. METHODS: We reanalyzed all consecutive ECGs of Swiss citizens who underwent conscription for the army between March 1, 2004, and July 31,2006. All ECGs with the diagnosis preexcitation were included in the present study. RESULTS: We analyzed ECGs of 41,699 male conscripts. Mean age was 19.2 ± 1.1 years. Preexcitation was found in 53 individuals. The length of the delta wave was 46 ± 10 ms. The most frequent localization of the accessory pathway was the left free wall. CONCLUSION: The prevalence of preexcitation in young, predominantly male conscripts is 0.13%. This is comparable with previous findings in children.

Assessment of systolic and diastolic function in heart failure using ambulatory monitoring with acoustic cardiography.

INTRODUCTION. The circadian variation of heart function and heart sounds in patients with and without heart failure (HF) is poorly understood. We hypothesized HF patients would exhibit less circadian variation with worsened cardiac function and sleep apnea. METHODS. We studied 67 HF patients (age 67.4 ± 8.2 years; 42% acute HF) and 63 asymptomatic control subjects with no history of HF (age 61.6 ± 7.7 years). Subjects wore a heart sound/ECG/respiratory monitor. The data were analyzed for sleep apnea, diastolic heart sounds, and systolic time intervals. RESULTS. The HF group had significantly greater prevalence of the third heart sound and prolongation of electro-mechanical activation time, while the control group had an age-related increase in the prevalence of the fourth heart sound. The control group showed more circadian variation in cardiac function. The HF subjects had more sleep apnea and higher occurrence of heart rate non-dipping. CONCLUSIONS. The control subjects demonstrated an increasing incidence of diastolic dysfunction with age, while systolic function was mostly unchanged with aging. Parameters related to systolic function were significantly worse in the HF group with little diurnal variation, indicating a constant stimulation of sympathetic tone in HF and reduction of diurnal regulation.

Noninvasive detection of left-ventricular systolic dysfunction by acoustic cardiography in atrial fibrillation.

Objectives. Assessment of left ventricular (LV) systolic function in patients with atrial fibrillation can be difficult. Acoustic cardiography provides several parameters for quantifying LV systolic function. We evaluated the ability of acoustic cardiography to detect LV systolic dysfunction in patients with and without atrial fibrillation. Design. We studied 194 patients who underwent acoustic cardiography and cardiac catheterization including measurement of angiographic ejection fraction (EF) and maximum LV dP/dt. LV systolic dysfunction was defined as LV maximum dP/dt <1600 mmHg/s. Acoustic cardiographic parameters included electromechanical activation time (EMAT) and the systolic dysfunction index (SDI). Results. Acoustic cardiography detected systolic dysfunction with high specificity and moderate sensitivity with similar performance to EF (sensitivity/specificity without afib: EMAT 30/96, SDI 40/90, EF at 35% 30/96; sensitivity/specificity with afib: EMAT 64/82, SDI 59/100, EF at 35% 45/82). Conclusions. Acoustic cardiography can be used for diagnosis of LV systolic dysfunction in atrial fibrillation.