16 research outputs found
Unidentified candidates for cardiac resynchronization therapy: guideline adherence in a large academic outpatient clinic in the Netherlands
Cardiac resynchronization therapy (CRT) reduces mortality and morbidity in patients with heart failure, diminished left ventricular function, and prolonged QRS duration. We investigated adherence to the CRT guidelines and screened for unidentified CRT candidates. Every unique patient visiting the outpatient clinic during three months was analyzed. In patients with QRS duration ≥120 ms or a paced QRS duration ≥200 ms on the electrocardiogram (ECG), left ventricular ejection fraction (LVEF), and New York Heart Association functional class were retrieved from hospital records and compared with the institutional implantable cardioverter defibrillator/pacemaker implantation database. The appropriateness of CRT indication was studied in patients who previously received CRT. QRS duration was 91% of patients fulfilling guideline criteria received CRT, and 8.2% of patients were unidentified. Systematic ECG screening of every patient may prove a simple tool to detect CRT candidates who were otherwise unrecognize
Acetylcholine Delays Atrial Activation to Facilitate Atrial Fibrillation
Background: Acetylcholine (ACh) shortens action potential duration (APD) in human atria. APD shortening facilitates atrial fibrillation (AF) by reducing the wavelength for reentry. However, the influence of ACh on electrical conduction in human atria and its contribution to AF are unclear, particularly when combined with impaired conduction from interstitial fibrosis. Objective: To investigate the effect of ACh on human atrial conduction and its role in AF with computational, experimental, and clinical approaches. Methods: S1S2 pacing (S1 = 600 ms and S2 = variable cycle lengths) was applied to the following human AF computer models: a left atrial appendage (LAA) myocyte to quantify the effects of ACh on APD, maximum upstroke velocity (Vmax), and resting membrane potential (RMP); a monolayer of LAA myocytes to quantify the effects of ACh on conduction; and 3) an intact left atrium (LA) to determine the effects of ACh on arrhythmogenicity. Heterogeneous ACh and interstitial fibrosis were applied to the monolayer and LA models. To corroborate the simulations, APD and RMP from isolated human atrial myocytes were recorded before and after 0.1 μM ACh. At the tissue level, LAAs from AF patients were optically mapped ex vivo using Di-4-ANEPPS. The difference in total activation time (AT) was determined between AT initially recorded with S1 pacing, and AT recorded during subsequent S1 pacing without (n = 6) or with (n = 7) 100 μM ACh. Results: In LAA myocyte simulations, S1 pacing with 0.1 μM ACh shortened APD by 41 ms, hyperpolarized RMP by 7 mV, and increased Vmax by 27 mV/ms. In human atrial myocytes, 0.1 μM ACh shortened APD by 48 ms, hyperpolarized RMP by 3 mV, and increased Vmax by 6 mV/ms. In LAA monolayer simulations, S1 pacing with ACh hyperpolarized RMP to delay total AT by 32 ms without and 35 ms with fibrosis. This led to unidirectional conduction block and sustained reentry in fibrotic LA with heterogeneous ACh during S2 pacing. In AF patient LAAs, S1 pacing with ACh increased total AT from 39.3 ± 26 ms to 71.4 ± 31.2 ms (p = 0.036) compared to no change without ACh (56.7 ± 29.3 ms to 50.0 ± 21.9 ms, p = 0.140). Conclusion: In fibrotic atria with heterogeneous parasympathetic activation, ACh facilitates AF by shortening APD and slowing conduction to promote unidirectional conduction block and reentry
Feasibility of a semi-automated method for cardiac conduction velocity analysis of high-resolution activation maps
Myocardial conduction velocity is important for the genesis of arrhythmias. In the normal heart, conduction is primarily dependent on fiber direction (anisotropy) and may be discontinuous at sites with tissue heterogeneities (trabeculated or fibrotic tissue). We present a semi-automated method for the accurate measurement of conduction velocity based on high-resolution activation mapping following central stimulation. The method was applied to activation maps created from myocardium from man, sheep and mouse with anisotropic and discontinuous conduction. Advantages of the presented method over existing methods are discusse
Epicardial confirmation of conduction block during thoracoscopic surgery for atrial fibrillation - a hybrid surgical-electrophysiological approach
Background: Totally thoracoscopic epicardial pulmonary vein ablation is an emerging treatment of atrial fibrillation (AF). A hybrid surgical-electrophysiological procedure with periprocedural confirmation of conduction block might reduce recurrences of AF or atrial tachycardia and improve surgical success. Methods and results: We report our joint surgical-electrophysiological approach for confirmation of conduction block across pulmonary vein ablation lines and those compartmentalizing the left atrium during totally thoracoscopic surgery. A diagnostic electrophysiology (EP) catheter positioned under the left atrium is used as reference and a custom-made multi-electrode for recording. Determination of conduction block across the pulmonary vein (PV) ablation lines requires measurement of activation time differences of milliseconds. Second, a stable reference electrogram to which to relate local activation time is required. Third, the recording electrode terminals and the inter-electrode distance should be small to prevent recording of far field activity and to allow recording of very small electrograms. We confirm entry and exit block and determine conduction block across linear ablation lines with differential pacing. Conclusion: A joint surgical-electrophysiological protocol for confirmation of conduction block across PV isolation lines and left atrial ablation lines is feasible and might prevent recurrences and further improve the success of minimally invasive surgery for A
Electrocardiographic P wave changes after thoracoscopic pulmonary vein isolation for atrial fibrillation
Changes in P wave duration (PWD) and P wave area (PWA) have been described following catheter ablation for atrial fibrillation (AF). We hypothesize that video-assisted thoracoscopic pulmonary vein isolation (VATS-PVI) for AF results in decrease of PWD, PWA and P wave dispersion, which may resemble reverse electrical remodeling of the atrium after restoration of sinus rhythm. VATS-PVI consisted of PVI and ganglionic plexus ablation in 29 patients (mean age, 59 ± 7 years; 23 males; 17 paroxysmal AF) and additional left atrial lesions in patients with persistent AF. PWD and PWA were measured in ECG lead II, aVF and V2 of ECGs during sinus rhythm before, directly after, and 6 months postprocedure. P wave dispersion was derived from the 12 lead ECG. Prior to VATS-PVI, PWD did not correlate with left atrial size and no difference in left atrial size was found between patients with paroxysmal or persistent AF (p = 0.27). Following VATS-PVI, PWD initially prolonged in all patients from 115 ± 4.6 ms to 131 ± 3.6 ms (p  < 0.01) but shortened to 99 ± 3.2 ms after 6 months (p  < 0.01). PWA was 5.60 ± 0.32 mV*ms at baseline, 6.44 ± 0.32 mV*ms post-VATS-PVI (P = NS), and 5.40 ± 0.28 mV*ms after 6 months (p = NS vs. baseline, p  < 0.05 vs. post-VATS-PVI). P wave dispersion decreased in the persistent AF group from baseline 67 ± 3.3 to 64 ± 2.5 ms post-VATS-PVI (p = 0.30) and to 61 ± 3.4 ms after 6 months (p  < 0.05). PWD increases significantly directly after successful VATS-PVI in both groups. There was significant decrease in PWD after 6 months. Similarly, P wave dispersion decreased in the persistent group. These changes suggest an immediate procedure related effect, but the later changes may represent reverse electrical atrial remodeling following cessation of A
Navigating the mini-maze: systematic review of the first results and progress of minimally-invasive surgery in the treatment of atrial fibrillation
In this paper we present a systematic literature overview and analysis of the first results and progress made with minimally-invasive surgery using RF energy in the treatment of AF. The minimally-invasive treatment for atrial fibrillation (AF) tries to combine the success rate of surgical treatment with a less invasive approach to surgery. It has the additional potential advantage of ganglion plexus (GP) ablation and left atrial appendage exclusion. Furthermore, additional left atrial ablation lines (ALAL) can be created in non-paroxysmal AF patients. For the search query multiple databases were used. Exclusion and inclusion criteria were applied to select the publications to be screened. All remaining articles were critically appraised and only relevant and valid articles were included in our results. Twenty-three studies were included. In 15 studies GPs around the pulmonary veins were ablated. In four studies ALAL were performed. Single procedure success rate was 69% (95% CI, range 58%-78%) without antiarrhythmic drugs (AAD) and 79% (95% CI, range 71%-85%) with AAD at one year follow-up. Mortality was 0.4%, and various complications were reported (3.2% surgical, 3.2% post-surgical, 2.6% cardiac, 2.1% pulmonary, 1.7% other). Twenty-three studies of minimally-invasive surgery for AF have been reviewed with success rates between that of the standard maze procedure and catheter ablation. These first combined results show promise; however, minimally-invasive surgery is still evolving, for instance by the recent inclusion of electrophysiological endpoints. Furthermore, the type of ALAL and the additional value of GP ablation have to be elucidate
Documented atrial fibrillation recurrences after pulmonary vein isolation are associated with diminished quality of life
Pulmonary vein isolation (PVI) aims at eliminating symptomatic atrial fibrillation. In this regard, the most relevant indication for this procedure is the reduction of symptoms and improvement of quality of life (QoL) in patients who remain symptomatic despite antiarrhythmic drug treatment. We investigated the relation between documented atrial fibrillation recurrences and QoL in patients after PVI. One hundred and six PVIs were performed in 99 patients. Follow-up was mainly performed at referring hospitals. Short Form 36 (SF-36) QoL questionnaires were completed before and 1 year after PVI. Electrocardiographic recordings from the first postprocedural year were retrospectively collected, 3 months blanking excluded. Atrial fibrillation recurrence was defined as any recurrence of atrial arrhythmia documented on ECG or 24-h-Holter. Before PVI, patients had lower QoL than the general Dutch population in 7/8 SF-36 questionnaire subscales (sumQoL 419.4 ± 161 vs. 617.9, P  < 0.001). Atrial fibrillation recurred in 52 (49%) patients. In these patients, four subscales increased following PVI (physical functioning P  < 0.001, role physical P = 0.006, bodily pain P = 0.011 and social functioning P = 0.047). SumQoL remained lower than the general Dutch population (546.7 ± 157, P = 0.003). In patients without documented recurrences, QoL improved to a level similar to that of the general Dutch population (602.9 ± 148; P = 0.46). The number of electrocardiographic recordings was lower in the group without documented recurrences (2.5 ± 1.8 vs. 3.8 ± 1.7, P = 0.002). In patients without documentation of atrial fibrillation, QoL increased up to the level of the general population after PVI, but it remained lower in patients with recurrences. In the latter group more ECGs were done, suggesting that QoL relates particularly to symptomatic episodes. Improvement of QoL is therefore an important attribute of PV
Quality of life improves after thoracoscopic surgical ablation of advanced atrial fibrillation: Results of the Atrial Fibrillation Ablation and Autonomic Modulation via Thoracoscopic Surgery (AFACT) study
We evaluated health-related quality of life at 12 months after thoracoscopic surgical ablation in patients enrolled in the Atrial Fibrillation Ablation and Autonomic Modulation via Thoracoscopic Surgery study. The Atrial Fibrillation Ablation and Autonomic Modulation via Thoracoscopic Surgery study assessed the efficacy and safety of ganglion plexus ablation in patients with symptomatic advanced atrial fibrillation undergoing thoracoscopic surgical ablation. Patients (n = 240) underwent thoracoscopic pulmonary vein isolation with additional ablation lines in patients with persistent atrial fibrillation. Subjects were randomized to additional ganglion plexus ablation or control. Short Form 36 quality of life questionnaires were collected at baseline and at 6 and 12 months of follow-up. A total of 201 patients were eligible for quality of life analysis (age 59 ± 8 years, 72% were men, 68% had an enlarged left atrium, 57% had persistent atrial fibrillation). Patients improved in physical and mental health at 6 months (both P < .01) and 12 months (both P < .01) relative to baseline, with no difference between the ganglion plexus (n = 101) and control (n = 100) groups. Short Form 36 subscores in patients with 1 or no atrial fibrillation recurrences were similar to those in the general Dutch population after 12 months. Patients with multiple atrial fibrillation recurrences (30%) improved in mental (P < .01), but not physical health, and 6 of 8 Short Form 36 subscales remained below those of the general Dutch population. Patients with irreversible, but not with reversible procedural complications had persistently diminished quality of life scores at 12 months. Thoracoscopic surgery for advanced atrial fibrillation results in improvement in quality of life, regardless of additional ganglion plexus ablation. Quality of life in patients with no or 1 atrial fibrillation recurrence increased to the level of the general Dutch population, whereas in patients with multiple atrial fibrillation recurrences quality of life remained lower. Irreversible but not reversible procedural complications were associated with persistently lower quality of lif
Thoracoscopic Video-Assisted Pulmonary Vein Antrum Isolation, Ganglionated Plexus Ablation and Periprocedural Confirmation of Ablation Lesions. First Results of a Hybrid Surgical-Electrophysiological Approach for Atrial Fibrillation
BACKGROUND: -Thoracoscopic pulmonary vein isolation (PVI) and ganglionated plexus (GP) ablation is a novel approach in the treatment of atrial fibrillation (AF). We hypothesize that meticulous electrophysiological confirmation of PVI results in fewer recurrences of AF during follow-up. METHODS AND RESULTS: -Surgery was performed through three ports bilaterally. GPs were localized and subsequently ablated. PVI was performed and entry and exit block was confirmed. Additional left atrial ablation lines (ALAL) were created, and conduction block verified, in patients with non-paroxysmal AF. The left atrial appendage was removed. Freedom of AF was assessed by ECGs and Holter monitoring every 3 months or during symptoms of arrhythmia. Anti-arrhythmic drugs (AAD) were discontinued after 3 months and oral anticoagulants were discontinued according to the guidelines. Thirty-one patients were treated (16 paroxysmal AF, 13 persistent AF, 2 long standing persistent (LSP) AF). Thirteen patients with non-paroxysmal received ALAL. After one year, 19/22 patients (86%) had no recurrences of AF, atrial flutter or atrial tachycardia and were not using AAD (11/12 paroxysmal, 7/9 persistent, 1/1 LSP). Three patients had a sternotomy because of uncontrolled bleeding during thoracoscopic surgery. Four adverse events were; 1 hemothorax, 1 pneumothorax and 2 pneumonia. No thromboembolic complications or mortality occurred. CONCLUSIONS: -Thoracoscopic surgery with PVI and GP ablation for AF is a safe and successful procedure with a single procedure success rate of 86% at one year. Electrophysiological guided thorough PVI and ALAL creation presumably contributes in achieving a high success rate in the surgical treatment of A
Ganglion Plexus Ablation in Advanced Atrial Fibrillation: The AFACT Study
Patients with long duration of atrial fibrillation (AF), enlarged atria, or failed catheter ablation have advanced AF and may require more extensive treatment than pulmonary vein isolation. The aim of this study was to investigate the efficacy and safety of additional ganglion plexus (GP) ablation in patients undergoing thoracoscopic AF surgery. Patients with paroxysmal AF underwent pulmonary vein isolation. Patients with persistent AF also received additional lines (Dallas lesion set). Patients were randomized 1:1 to additional epicardial ablation of the 4 major GPs and Marshall's ligament (GP group) or no extra ablation (control) and followed every 3 months for 1 year. After a 3-month blanking period, all antiarrhythmic drugs were discontinued. Two hundred forty patients with a mean AF duration of 5.7 ± 5.1 years (59% persistent) were included. Mean procedure times were 185 ± 54 min and 168 ± 54 min (p = 0.015) in the GP (n = 117) and control groups (n = 123), respectively. GP ablation abated 100% of evoked vagal responses; these responses remained in 87% of control subjects. Major bleeding occurred in 9 patients (all in the GP group; p <0.001); 8 patients were managed thoracoscopically, and 1 underwent sternotomy. Sinus node dysfunction occurred in 12 patients in the GP group and 4 control subjects (p = 0.038), and 6 pacemakers were implanted (all in the GP group; p = 0.013). After 1 year, 4 patients had died (all in the GP group, not procedure related; p = 0.055), and 9 were lost to follow-up. Freedom from AF recurrence in the GP and control groups was not statistically different whether patients had paroxysmal or persistent AF. At 1 year, 82% of patients were not taking antiarrhythmic drugs. GP ablation during thoracoscopic surgery for advanced AF has no detectable effect on AF recurrence but causes more major adverse events, major bleeding, sinus node dysfunction, and pacemaker implantation. (Atrial Fibrillation Ablation and Autonomic Modulation via Thoracoscopic Surgery [AFACT]; NCT01091389