Long-term outcome after totally thoracoscopic ablation for atrial fibrillation.

INTRODUCTION: Totally thoracoscopic ablation for symptomatic atrial fibrillation (AF) refractory to drug or catheter based therapy is indicated as a Class 2A recommendation according to latest guidelines. Evidence for long-term rhythm control and stroke reduction is limited. The aim of this study was to report on long-term outcome after totally thoracoscopic ablation. METHODS AND RESULTS: In total 82 consecutive patients were included that underwent totally thoracoscopic ablation including left appendage closure (2012-2013). The primary outcome was freedom from atrial arrhythmia recurrence. Secondary outcomes were survival, freedom from cerebrovascular events, freedom from reablation and definite pacemaker implantation. The mean age was 59.9 ± 8.6 years and 71% were male. The mean CHA2 DS2 -VASc score was 1.2 ± 1.0. The overall freedom from atrial arrhythmia was 60% after a mean follow up of 4.0 ± 0.6 years. Freedom from cerebrovascular events was 98.8% after mean follow-up of 4.4 ± 0.3 years and overall survival was 98.8%, with one noncardiac related death. The observed rate of ischemic stroke, hemorrhagic stroke or transient ischemic attack was 0.3 per 100 patient-years. CONCLUSIONS: Totally thoracoscopic ablation is an effective sustainable rhythm control therapy for AF with a reasonable recurrence rate and low stroke rate when performed in dedicated AF centers.

Thoracoscopic ablation for the treatment of atrial fibrillation: a systematic outcome analysis of a multicentre cohort.

AIMS: To perform a systematic outcome analysis in order to provide cardiologists and general pactitioners with more adequate information to guide their decision making regarding rhythm control. Totally thoracoscopic maze (TTmaze) for the treatment of atrial fibrillation (AF) is recommended as a Class 2a indication mainly based on single centre studies including small patient cohorts and inconsistent lesion sets. METHODS AND RESULTS: We studied consecutive patients undergoing TTmaze in three European referral centres (2012-15). Primary outcome was freedom from atrial tachyarrhythmia (ATA). Secondary outcomes were 30-day complications, the composite endpoint of ischaemic stroke, haemorrhagic stroke or transient ischaemic attack (TIA), all-cause mortality, and predictors of ATA recurrence. Four hundred and seventy-five patients were included, with a mean age of 61 ± 9 years and 69.5% male. The mean CHA2DS2-VASc score was 1.7 ± 1.3. The overall freedom from ATA was 68.8% after a mean follow-up period of 20 ± 9 months. Freedom from ATA was 72.7% for paroxysmal AF, 68.9% for persistent AF, and 54.2% for longstanding persistent AF. Multivariate analysis revealed female gender [hazard ratio (HR): 1.87, P = 0.005], in-hospital AF (HR: 1.95, P = 0.040), longer duration of preoperative AF (HR: 1.06, P = 0.003) and mitral regurgitation (HR: 1.84, P = 0.025) as independent predictors of ATA recurrence. Overall 30-day freedom from any complication was 92.4%. Freedom from cerebrovascular events after mean follow-up of 30 ± 16 months was 98.7% and overall survival was 98.3%. The observed rate of ischaemic stroke, haemorrhagic stroke, or TIA was low (0.5 per 100 patient-years). CONCLUSION: Totally thoracoscopic maze is a safe and effective rhythm control therapy.

Rationale and design of the PRAETORIAN trial: a Prospective, RAndomizEd comparison of subcuTaneOus and tRansvenous ImplANtable cardioverter-defibrillator therapy.

BACKGROUND: Implantable cardioverter-defibrillators (ICDs) are widely used to prevent fatal outcomes associated with life-threatening arrhythmic episodes in a variety of cardiac diseases. These ICDs rely on transvenous leads for cardiac sensing and defibrillation. A new entirely subcutaneous ICD overcomes problems associated with transvenous leads. However, the role of the subcutaneous ICD as an adjunctive or primary therapy in patients at risk for sudden cardiac death is unclear. STUDY DESIGN: The PRAETORIAN trial is an investigator-initiated, randomized, controlled, multicenter, prospective 2-arm trial that outlines the advantages and disadvantages of the subcutaneous ICD. Patients with a class I or IIa indication for ICD therapy without an indication for bradypacing or tachypacing are included. A total of 700 patients are randomized to either the subcutaneous or transvenous ICD (1:1). The study is powered to claim noninferiority of the subcutaneous ICD with respect to the composite primary endpoint of inappropriate shocks and ICD-related complications. After noninferiority is established, statistical analysis is done for potential superiority. Secondary endpoint comparisons of shock efficacy and patient mortality are also made. CONCLUSION: The PRAETORIAN trial is a randomized trial that aims to gain scientific evidence for the use of the subcutaneous ICD compared with the transvenous ICD in a population of patients with conventional ICD with respect to major ICD-related adverse events. This trial is registered at ClinicalTrials.gov with trial ID NCT01296022.

Anatomical perspective on radiofrequency ablation of AV nodal reentry tachycardia after Mustard correction for transposition of the great arteries.

A case of radiofrequency catheter ablation of atrioventricular (AV) nodal reentry tachycardia, in a patient with transposition of the great arteries after venous rerouting according to Mustard, is described. An electroanatomical map of the His and AV nodal region was created from inside the systemic venous atrium. Retrograde mapping of the pulmonary venous atrium was performed and the arterial catheter retracted to a position in close proximity to the venous catheter inside the intraatrial baffle. This position was chosen to deliver radiofrequency current.

Requirement for coronary sinus lead interventions and effectiveness of endovascular replacement during long-term follow-up after implantation of a resynchronization device.

AIMS: The aim of this study was to assess the requirement for coronary sinus (CS) lead intervention after cardiac resynchronization therapy (CRT) and to evaluate the effectiveness of endovascular replacement. METHODS AND RESULTS: All patients receiving a CRT device with CS lead in the Leiden University Medical Center in the period from 1999 to 2007 were prospectively evaluated and followed. Five hundred and seventy-seven patients were successfully implanted with a CRT device. Nine (1.6%) patients were lost to follow-up. The remaining 568 patients were included in the analysis. During a median follow-up time of 645 days (inter-quartile range, 260-1148), 7% of the patients required a CS lead intervention. Cause of the intervention was an elevated threshold (n = 13), loss of capture (n = 20), or intractable phrenic nerve stimulation (n = 6). Fifteen patients (38%) required a CS lead intervention before first scheduled follow-up (2 months after implantation). Thirteen patients (33%) warranted a CS lead intervention more than 6 months after implantation. The first endovascular replacement was successful in 86% (32 of 37), whereas a second endovascular approach failed in 66% (2 of 3). CONCLUSION: The long-term requirement for CS lead interventions is 7%. Endovascular repositioning or replacement is successful in the majority of cases.

Totally thoracoscopic left atrial Maze: standardized, effective and safe.

OBJECTIVES: The totally thoracoscopic left atrial Maze (TT-Maze) is a relatively new surgical solution for the treatment of atrial fibrillation (AF). The procedure consists of a complete left atrial Maze, which is performed by video-assisted thoracoscopy with the use of radiofrequency ablation. We describe our rhythm results as well as our learning curve experience of the TT-Maze. METHODS: To evaluate the learning curve, all consecutive patients who underwent a TT-Maze and were operated by one surgeon (Bart P. Van Putte) were included in the study. The endpoint of surgery was sinus rhythm with a bidirectional block of the box and pulmonary veins. RESULTS: A total of 83 patients were included. Fifty percent of the patients had paroxysmal AF. The mean indexed left atrial volume was 44 ± 15 ml/m(2) and 38% of the patients had a previous catheter ablation for AF. During a mean follow-up of 10.9 ± 4.9 months, there were no major events. At latest follow-up, 82% of the patients did not have a single registration of AF or other atrial tachyarrhythmias longer than 30 s. Patients without AF were also free from anti-arrhythmic drugs in 90% of the cases, free from coumadins or direct oral anticoagulants in 63% of the cases and free from both in 58% of the cases. CONCLUSIONS: After almost 1-year follow-up, the TT-Maze is proved to be a successful, safe and reproducible strategy for the treatment of all types of AF including patients with enlarged left atria and previously failed catheter ablation.

Non-sustained ventricular tachycardia in patients with congenital heart disease: An important sign?

BACKGROUND: Sustained ventricular tachycardia (susVT) and ventricular fibrillation (VF) are observed in adult patients with congenital heart disease (CHD). These dysrhythmias may be preceded by non-sustained ventricular tachycardia (NSVT). The aims of this study are to examine the 1] time course of ventricular tachyarrhythmia (VTA) in a large cohort of patients with various CHDs and 2] the development of susVT/VF after NSVT. METHODS: In this retrospective study, patients with VTA on ECG, 24-hour Holter or ICD-printout or an out-of-hospital-cardiac arrest due to VF were included. In patients with an ICD, the number of shocks was studied. RESULTS: Patients (N=145 patients, 59% male) initially presented with NSVT (N=103), susVT (N=25) or VF (N=17) at a mean age of 40 ± 14 years. Prior to VTA, 58 patients had intraventricular conduction delay, 14 an impaired ventricular dysfunction and 3 had coronary artery disease. susVT/VF rarely occurred in patients with NSVT (N=5). Fifty-two (36%) patients received an ICD; appropriate and inappropriate shocks, mainly due to supraventricular tachycardia (SVT), occurred in respectively 15 (29%) (NSVT: N=1, susVT: N=9, VF: N=5) and 12 (23%) (NSVT: N=4, susVT: N=5, VF: N=3) patients. CONCLUSIONS: VTA in patients with CHD appear on average at the age of 40 years. susVT/VF rarely developed in patients with only NSVT, whereas recurrent episodes of susVT/VF frequently developed in patients initially presenting with susVT/VF. Hence, a wait-and-see treatment strategy in patients with NSVT and aggressive therapy of both episodes of VTA and SVT in patients with susVT/VF seems justified.

Left ventricular dyssynchrony predicts response and prognosis after cardiac resynchronization therapy.

OBJECTIVES: This study was designed to predict the response and prognosis after cardiac resynchronization therapy (CRT) in patients with end-stage heart failure (HF). BACKGROUND: Cardiac resynchronization therapy improves HF symptoms, exercise capacity, and left ventricular (LV) function. Because not all patients respond, preimplantation identification of responders is needed. In the present study, response to CRT was predicted by the presence of LV dyssynchrony assessed by tissue Doppler imaging. Moreover, the prognostic value of LV dyssynchrony in patients undergoing CRT was assessed. METHODS: Eighty-five patients with end-stage HF, QRS duration >120 ms, and left bundle-branch block were evaluated by tissue Doppler imaging before CRT. At baseline and six months follow-up, New York Heart Association functional class, quality of life and 6-min walking distance, LV volumes, and LV ejection fraction were determined. Events (death, hospitalization for decompensated HF) were obtained during one-year follow-up. RESULTS: Responders (74%) and nonresponders (26%) had comparable baseline characteristics, except for a larger dyssynchrony in responders (87 +/- 49 ms vs. 35 +/- 20 ms, p < 0.01). Receiver-operator characteristic curve analysis demonstrated that an optimal cutoff value of 65 ms for LV dyssynchrony yielded a sensitivity and specificity of 80% to predict clinical improvement and of 92% to predict LV reverse remodeling. Patients with dyssynchrony >/=65 ms had an excellent prognosis (6% event rate) after CRT as compared with a 50% event rate in patients with dyssynchrony <65 ms (p < 0.001). CONCLUSIONS: Patients with LV dyssynchrony >/=65 ms respond to CRT and have an excellent prognosis after CRT.

Comparison of effectiveness of cardiac resynchronization therapy in patients with versus without diabetes mellitus.

The effect of long-term cardiac resynchronization therapy (CRT) was evaluated in 32 patients with heart failure (HF) and diabetes mellitus (DM) compared with 65 patients with HF and no DM. Clinical parameters were obtained before and after 6 months of CRT. Long-term follow-up was performed <2 years after implantation.

Comparison of effectiveness of cardiac resynchronization therapy in patients <70 versus > or =70 years of age.

In the present study, the effects of cardiac resynchronization therapy (CRT) in elderly patients were evaluated. The study included 170 consecutive patients whose clinical and echocardiographic improvements were evaluated after 6 months of follow-up. Survival was evaluated up to 2 years. The effects of CRT in elderly patients (age > or =70 years) were compared with those in younger patients (age <70 years).

Frequency of left ventricular dyssynchrony in patients with heart failure and a narrow QRS complex.

Cardiac resynchronization therapy (CRT) is considered a major advance in the treatment of patients with heart failure. The presence of left ventricular (LV) dyssynchrony seems mandatory for a positive response to CRT. Currently, only patients with wide QRS complexes are considered for CRT, although patients with narrow QRS complexes may also have LV dyssynchrony. In the present study, the incidence of LV dyssynchrony was prospectively evaluated in 64 patients with heart failure and narrow QRS complexes using tissue Doppler imaging.

Effect of cardiac resynchronization therapy on inducibility of ventricular tachyarrhythmias in cardiac arrest survivors with either ischemic or idiopathic dilated cardiomyopathy.

We evaluated whether long-term cardiac resynchronization therapy affects the inducibility of ventricular tachyarrhythmias in relation to reverse remodeling in cardiac arrest survivors with either ischemic or idiopathic dilated cardiomyopathy. Clinical, electrophysiologic, and echocardiographic data of 18 patients were obtained before and after 6 months of cardiac resynchronization.

Dispersion of repolarization in cardiac resynchronization therapy.

BACKGROUND: Proarrhythmic effects of cardiac resynchronization therapy (CRT) as a result of increased transmural dispersion of repolarization (TDR) induced by left ventricular (LV) epicardial pacing in a subset of vulnerable patients have been reported. The possibility of identifying these patients by ECG repolarization indices has been suggested. OBJECTIVES: The purpose of this study was to test whether repolarization indices on the ECG can be used to measure dispersion of repolarization during pacing. METHODS: CRT devices of 28 heart failure patients were switched among biventricular, LV, and right ventricular (RV) pacing. ECG indices proposed to measure dispersion of repolarization were calculated. The effects of CRT on repolarization were simulated in ECGSIM, a mathematical model of electrocardiogram genesis. TDR was calculated as the difference in repolarization time between the epicardial and endocardial nodes of the heart model. PATIENTS: The interval from the apex to the end of the T wave was shorter during biventricular pacing (102 +/- 18 ms) and LV pacing (106 +/- 21 ms) than during RV pacing (117 +/- 22 ms, P < or =.005). T-wave amplitude and area were low during biventricular pacing (287 +/- 125 microV and 56 +/- 22 microV.s, respectively, P = .0006 vs RV pacing). T-wave complexity was high during biventricular pacing (0.42 +/- 0.26, P = .004 vs RV pacing). Simulations: Repolarization patterns were highly similar to the preceding depolarization patterns. The repolarization patterns of different pacing modes explained the observed magnitudes of the ECG repolarization indices. Average and local TDR were not different between pacing modes. CONCLUSION: In patients treated with CRT, ECG repolarization indices are related to pacing-induced activation sequences rather than transmural dispersion. TDR during biventricular and LV pacing is not larger than TDR during conventional RV endocardial pacing.

Time Course of Atrial Fibrillation in Patients With Congenital Heart Defects.

BACKGROUND: The incidence of atrial fibrillation (AF) is rising in the aging patients with congenital heart defects (CHD). However, studies reporting on AF in patients with CHD are scarce. The aim of this multicenter study was to examine in a large cohort of patients with a variety of CHD: (1) the age of onset and initial treatment of AF, coexistence of atrial tachyarrhythmia and (2) progression of paroxysmal to (long-standing) persistent/permanent AF during long-term follow-up. METHODS AND RESULTS: Patients (n=199) with 15 different CHD and documented AF episodes were studied. AF developed at 49±17 years. Regular atrial tachycardia (AT) coexisting with AF occurred in 65 (33%) patients; 65% initially presented with regular AT. At the end of a follow-up period of 5 (0-24) years, the ECG showed AF in 81 patients (41%). In a subgroup of 114 patients, deterioration from paroxysm of AF to (long-standing) persistent/permanent AF was observed in 29 patients (26%) after only 3 (0-18) years of the first AF episode. Cerebrovascular accidents/transient ischemic attacks occurred in 26 patients (13%), although a substantial number (n=16) occurred before the first documented AF episode. CONCLUSIONS: Age at development of AF in patients with CHD is relatively young compared with the patients without CHD. Coexistence of episodes of AF and regular AT occurred in a considerable number of patients; most of them initially presented with regular AT. The fast and frequent progression from paroxysmal to (long-standing) persistent or permanent AF episodes justifies close follow-up and early, aggressive therapy of both AT and AF.

Effectiveness of resynchronization therapy in patients with end-stage heart failure.

Biventricular pacing has been introduced to treat patients with end-stage heart failure, and short-term results of this technique are promising. Because data on longer follow-up are limited to 3-month follow-up, the sustained effect of biventricular pacing is unclear and long-term survival is unknown. Forty patients with end-stage heart failure in New York Heart Association (NYHA) functional class III or IV with left ventricular (LV) ejection fraction (EF) <35%, QRS duration >120 ms, and left bundle branch block morphology received a biventricular pacemaker. At baseline, and at 3 and 6 months after implantation, the following parameters were evaluated: NYHA class, Minnesota quality-of-life score, QRS duration on surface electrocardiogram, 6-minute walking distance, and LVEF. Long-term follow-up was obtained for up to 2 years. All clinical parameters improved significantly at 3 months and remained unchanged at 6-month follow-up. LVEF increased from 24 +/- 9% to 34 +/- 11%. Before implantation, patients were hospitalized (for congestive heart failure) an average of 3.9 +/- 5.3 days/year compared with 0.5 +/- 1.5 days/year after implantation. Long-term follow-up showed a survival of 87.5% at 2 years. Thus, biventricular pacing resulted in improvement of symptoms and quality of life, accompanied by improvement in 6-minute walking distance and LVEF. These effects were observed at 3 months after implantation and were maintained at 6-month follow-up. Moreover, 2-year survival was excellent.

Comparison of response to cardiac resynchronization therapy in patients with sinus rhythm versus chronic atrial fibrillation.

Cardiac resynchronization therapy (CRT) is a new therapeutic option for patients who have drug-refractory end-stage heart failure. Much information has been obtained from patients who have sinus rhythm, but the use of CRT in patients who have chronic atrial fibrillation (AF) has not been studied extensively. Accordingly, we evaluated the clinical response and long-term survival rate of CRT in patients who had heart failure and chronic AF, and the results were compared with those in patients who had sinus rhythm and who underwent CRT. Sixty patients who had end-stage heart failure (30 had sinus rhythm and 30 had chronic AF), New York Heart Association classes III to IV, left ventricular ejection fraction <35%, QRS interval >120 ms, and a left bundle branch block received a biventricular pacemaker. New York Heart Association class, Minnesota Quality of Life score, and 6-minute walking distance were evaluated at baseline and after 6 months of CRT. Long-term follow-up was

Comparison of benefits from cardiac resynchronization therapy in patients with ischemic cardiomyopathy versus idiopathic dilated cardiomyopathy.

Cardiac resynchronization therapy (CRT) is a recently introduced therapeutic option for patients with severe heart failure and intraventricular conduction disturbances. However, it is estimated that 20% to 30% of patients may not respond to CRT. Patients with ischemic cardiomyopathy (IC) may respond less favorably to CRT compared with patients with idiopathic dilated cardiomyopathy (IDC). Accordingly, the beneficial effects of CRT were evaluated in 2 subsets of patients (IC and IDC). Seventy-four patients with end-stage heart failure, New York Heart Association (NYHA) class III or IV, left ventricular (LV) ejection fraction <35%, QRS >120ms, and left bundle branch block received a biventricular pacemaker. At baseline and 6 months after implantation these parameters were evaluated: NYHA class, Minnesota quality-of-life score, QRS duration, and 6-minute walking distance. LV ejection fraction and severity of mitral regurgitation were assessed before and 6 months after CRT using 2-dimensional echocardiography. Long-term follow-up and hospitalization rates were obtained up to 2 years. Of the 74 patients, 46% (n = 34) had IC and 54% (n = 40) IDC. At 6 months follow-up all clinical parameters, QRS duration, LV ejection fraction, and mitral regurgitation improved significantly in both groups. Long-term (2-year) follow-up showed a survival rate of 87.5% for patients with IDC and 88.3% for patients with IC. The percentages of responders to CRT (defined as an improvement in NYHA class >or=1 grade) were comparable in both groups (65% vs 71%). Therefore, the underlying etiology of heart failure (IC vs IDC) was not related to the response to CRT.

Effect of left ventricular remodeling after cardiac resynchronization therapy on frequency of ventricular arrhythmias.

We evaluated whether cardiac resynchronization therapy affects the prevalence of ventricular tachycardia in relation to reverse remodeling in patients with end-stage heart failure. Clinical, echocardiographic, and implantable cardioverter-defibrillator (ICD) data of 17 patients with ICDs were obtained before and after they had received an upgrade to an ICD-cardiac resynchronization therapy device.

Left ventricular dyssynchrony predicts benefit of cardiac resynchronization therapy in patients with end-stage heart failure before pacemaker implantation.

We evaluated patients with end-stage heart failure who have a high likelihood of response to cardiac resynchronization therapy (biventricular pacing). It appears that 20% of patients do not respond to this expensive therapy despite the use of selection criteria (dilated cardiomyopathy, heart failure, New York Heart Association class II or IV, left ventricular ejection fraction <35%, left bundle branch block, and QRS >120 ms). The presence of left ventricular dyssynchrony is needed to result in improvement after cardiac resynchronization therapy.