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Objective: Pulmonary vein isolation (PVI) using ablation energy appears an effective treatment for atrial fibrillation (AF) with a success rate of approximately 80%. However, post-procedural neurological complications still occur in 0.5-10% of all patients undergoing PVI, presumably due to embolism. Therefore, we investigated the occurrence of cerebral micro-embolic signals (MES) as a surrogate marker for the risk of neurological impairment of two different PVI methods: (1) percutaneous endocardial radio-frequency (RF) ablation and (2) thoracoscopic epicardial ablation using RF energy. Methods: Ten patients (eight persistent AF and two paroxysmal AF) underwent a minimally invasive thoracoscopic epicardial (EPI) RF ablation and 10 patients (one persistent AF and nine paroxysmal AF) underwent a percutaneous endocardial (ENDO) isolation. Transcranial Doppler (TCD) was used to detect an MES in the middle cerebral arteries. Results: An average of 5 (+/- 6) MES were detected during epicardial PVI procedure versus 3908 (+/- 2816) MES during percutaneous endocardial PVI procedure. During the ablation application period, respectively, 1 (+/- 1) and 2566 (+/- 2296) cerebral MES were detected. Conclusions: Cerebral micro-emboli during epicardial ablation are almost absent when compared to the thousands of emboli measured during percutaneous endocardial ablation. (C) 2009 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.

Objectives Our purpose was to evaluate the efficacy of antiarrhythmic drugs (AADs) in recurrent ventricular fibrillation (VF) associated with inferolateral early repolarization pattern on the electrocardiogram. Background Although an implantable cardioverter-defibrillator is the treatment of choice, additional AADs may be necessary to prevent frequent episodes of VF and reduce implantable cardioverter-defibrillator shock burden or as a lifesaving therapy in electrical storms. Methods From a multicenter cohort of 122 patients (90 male subjects, age 37 +/- 12 years) with idiopathic VF and early repolarization abnormality in the inferolateral leads, we selected all patients with more than 3 episodes of VF (multiple) including those with electrical storms (>= 3 VF in 24 h). The choice of AAD was decided by individual physicians. Follow-up data were obtained for all patients using monitoring with implantable defibrillator. Successful oral AAD was defined as elimination of all recurrences of VF with a minimal follow-up period of 12 months. Results Multiple episodes of VF were observed in 33 (27%) patients. Electrical storms (34 +/- 47 episodes) occurred in 16 and were unresponsive to beta-blockers (11 of 11), lidocaine/mexiletine (9 of 9), and verapamil (3 of 3), while amiodarone was partially effective (3 of 10). In contrast, isoproterenol infusion immediately suppressed electrical storms in 7 of 7 patients. Over a follow-up of 69 +/- 58 months, oral AADs were poorly effective in preventing recurrent VF: beta-blockers (2 of 16), verapamil (0 of 4), mexiletine (0 of 4), amiodarone (1 of 7), and class 1C AADs (2 of 9). Quinidine was successful in 9 of 9 patients, decreasing recurrent VF from 33 +/- 35 episodes to nil for 25 +/- 18 months. In addition, quinidine restored a normal electrocardiogram. Conclusions Multiple recurrences of VF occurred in 27% of patients with early repolarization abnormality and may be life threatening. Isoproterenol in acute cases and quinidine in chronic cases are effective AADs. (J Am Coll Cardiol 2009; 53: 612-9) (C) 2009 by the American College of Cardiology Foundation

Udgivelsesdato: 2008-Mar AIMS: Several clinical studies have shown that, in patients with intact atrioventricular (AV) conduction, unnecessary chronic right ventricular (RV) pacing can be detrimental. The managed ventricular pacing (MVP) algorithm is designed to give preference to spontaneous AV conduction, thus minimizing RV pacing. The clinical outcomes of MVP are being studied in several ongoing trials in patients undergoing a first device implantation, but it is unknown to what extent MVP is beneficial in patients with a history of ventricular pacing. The purpose of the Prefer for Elective Replacement MVP (PreFER MVP) study is to assess the superiority of the MVP algorithm to conventional pacemaker and implantable cardioverter-defibrillator programming in terms of freedom from hospitalization for cardiovascular causes in a population of patients exposed to long periods of ventricular pacing. METHODS AND RESULTS: PreFER MVP is a prospective, 1:1 parallel, randomized (MVP ON/MVP OFF), single-blinded multi-centre trial. The study population consists of patients with more than 40% ventricular pacing documented with their previous device. Approximately, 600 patients will be randomized and followed for at least 24 months. The primary endpoint comprises cardiovascular hospitalization. CONCLUSION: The PreFER MVP trial is the first large prospective randomized clinical trial evaluating the effect of MVP in patients with a history of RV pacing.

Cardiac resynchronization therapy (CRT) decreases muscle sympathetic nerve activity (MSNA) in patients with severe congestive heart failure (CHF) and cardiac asynchrony. Whether this affects equally patients who clinically respond or not to CRT is unknown. We tested the hypothesis that the favorable effects of CRT on MSNA disappear on CRT interruption only in those who respond to CRT. Twenty-three consecutive CHF patients participated in the study, among whom 16 presented a symptomatic improvement by one or more New York Heart Association (NYHA) functional classes 15 ± 5 mo after CRT (responders), and seven had not improved after 12 ± 4 mo of CRT (nonresponders). MSNA and echocardiographic recordings were obtained in random order during atrio-right ventricular pacing (ARV), without stimulation in patients who were not pacemaker dependent (OFF, n = 17), and during atrio-biventricular pacing (BIV). Responders had a longer 6-min walking distance, a lower NYHA class and brain natriuretic peptide levels, and a better quality of life than did nonresponders (all P < 0.05). MSNA increased by 25 ± 7% in the responders, whereas it remained unchanged in the nonresponders, when shifting from the BIV mode to a nonsynchronous condition (ARV and OFF modes) ( P < 0.01). Cardiac output decreased by 0.7 ± 0.2 l/min in the responders but did not change when shifting from the BIV mode to the nonsynchronous pacing mode in the nonresponders ( P < 0.01). In conclusion, reversible sympathoinhibition is a marker of the clinical response to CRT.

Since the first publication of the Brugada syndrome in 1992 several variants of this ECG pattern have been described. We report a very unusual case of preexcitation with changing electrocardiographic morphologies which appeared to be an association of a variable Brugada pattern with a persistent antegrade preexcitation.

Background— The origin of 40% of syncope cases remains unknown even after a complete diagnostic workup. Previous studies have suggested that ATP testing has value in selecting successful therapy. This patient-blinded, multicenter, randomized superiority trial tested whether, in patients with syncope of unknown origin, selecting cardiac pacing in those with a positive ATP test leads to fewer recurrences than those who do not receive pacing. Methods and Results— From 2000 to 2005, 80 consenting patients (mean age, 75.9±7.7 years; 81% women; 56% without diagnosed structural heart disease) with syncope of unknown origin and atrioventricular or sinoatrial block lasting >10 seconds (average, 17.9±6.8 seconds) under ATP administration (20-mg IV bolus) were recruited from 10 hospitals, implanted with programmable pacemakers, and randomized to either active pacing (dual-chamber pacing at 70 bpm) or backup pacing (atrial pacing at 30 bpm). Patients were followed up regularly for up to 5 years for any syncope recurrence, the primary outcome. Mean follow-up was 16 months. Syncope recurred in 8 of 39 patients (21%) randomized to active pacing and in 27 of 41 (66%) randomized to backup pacing (control), yielding a hazard ratio of 0.25 (95% confidence interval, 0.12–0.56). After recurrence, the 27 recurrent control patients were reprogrammed to active pacing, and only 1 reported subsequent syncope. Conclusion— This study suggests that, in elderly patients with syncope of unknown origin and positive ATP tests, active dual-chamber pacing reduces syncope recurrence risk by 75% (95% confidence interval, 44–88). Clinical Trial Registration— URL: http://www.controlled-trials.com/ISRCTN00029383 . Unique identifier: ISRCTN00029383.

Current European guidelines recommend prophylactic implantation of cardioverter defibrillators (ICDs) in patients with a reduced left ventricular ejection fraction (LVEF) who are not in NYHA class IV and have reasonable life expectancy. Cost and benefit implications of this recommendation have not been reported from a European perspective.Markov modelling estimated lifetime costs and effects [life years (LY) and quality-adjusted LY (QALY) gained] of prophylactic ICD implantation vs. conventional treatment, among patients with a reduced LVEF. Efficacy was estimated from a meta-analysis of mortality rates in the six primary prevention trials with inclusion criteria matching ACC/AHA/ESC Class I or IIa recommendations. Direct medical costs were estimated using Belgian national references. Costs and effects were discounted at 3 and 1.5% per annum, respectively. Probabilistic sensitivity and scenario analyses estimated the uncertainty around the incremental cost-effectiveness ratio. An ICD implantation increased the lifetime direct costs by euro 46,413. Estimated mean LY/QALY gained were 1.88/1.57, respectively. Probabilistic analysis estimated mean lifetime cost per QALY gained as euro 31,717 (95% CI: euro 19,760-euro 61,316). Cost-effectiveness was influenced most by ICD efficacy, time to replacement, utility, and patient age at implantation.In a European healthcare setting, prophylactic ICD implantation may be cost-effective if current guidelines for patients with a reduced LVEF are followed.

Assessment of volume in relation with left atrial (LA) shape alteration before and after PV isolation. We compared trapezoidal modification of LA using echocardiography with the ellipsoid formula (Eel) and CT, with both ellipsoid (CTel) and truncated cone formulas (CTtr), in 40 patients, before and ±3 months after AF ablation. A trapezoidal shape was present in 76.3% of patients. The different volume measurements were statistically correlated (r = 0.603–0.837, p

A 66-year-old patient had a left central venous catheter in place for 8 days. The catheter, which had to be removed, was withdrawn while the patient was in a 180° supine position during a Valsalva maneuver, with positive pressure during removal. A massage at the site of puncture was performed for 3 minutes, and a compressive plaster was applied. Several minutes after removal, the patient, still supine, needed to cough. He immediately became sweaty and breathless, with progressive improvement after 5 to 10 minutes. However, after ≈20 minutes, the patient was still coughing and became more breathless and somnolent, with an O2 saturation of 93% …

Background Pulmonary vein isolation (PVI) has become an established treatment for patients with atrial fibrillation (AF). But post-intervention complications like, TIA, stroke and cognitive decline, might occur. In this study the incidence of microembolic signals (MES) was determined during percutaneous PVI; non-irrigated tip radiofrequency (RF) ablation versus irrigated tip RF ablation. Methods and Results Twelve patients underwent PV catheter RF ablation. Two patient groups were selected; Group NON-IRRIGATED RF: a non-irrigated RF ablation catheter (temperature< 55°, power< 30 W) was used in 7 patients, Group IRRIGATED RF: an irrigated tip RF ablation catheter (temperature< 43°, power< 25 W) was used in 5 patients. Transcranial Doppler (TCD) was used to detect microembolic signals in the middle cerebral arteries. The duration of the procedure, the number of applications and the total ablation time was not different between both groups. In the IRRIGATED RF group versus the NON-IRRIGATED group less cerebral MES were detected during the complete procedure (1570 vs. 3515) and per 1 minute of ablation (4 vs.89). Conclusions Ablation of the pulmonary veins in a percutaneous endocardial approach causes a significant number of cerebral MES during the procedure. The cerebral MES detected during ablation are most likely gas bubbles and solid emboli due to overheating of the tissue and blood. Because a positive association between the number of cerebral MES and the risk of stroke and neurological impairment has been reported, the RF irrigated tip ablation catheter might be preferable in an effort to reduce the stroke risk. Number of MES during irrigated and non-irrigated PVI

Trans-septal approach has to be performed by trained cardiologists, and even after the obligatory learning curve it entails some risky complications. Sometimes the dilator and the introducer sheat passes through a narrow foramen ovale and glides into the left atrium without needle puncture. This seems to be a convenient …

A simplified technique to treat patients in stand-alone atrial fibrillation with a right thoracoscopic approach is described. An electrical isolation of the four pulmonary veins ( box lesion) is achieved with a microwave antenna.

Right ventricular perforation by a temporary endocardial pacing electrode can be fatal and needs to be detected promptly. This usually symptomatic situation is diagnosed by X-ray or echocardiographic findings. We present the case of a patient with an asymptomatic right ventricular perforation, in whom serial electrocardiograms enabled us to detect the displacement of the right ventricular lead.