|Cardiac resynchronization therapy in heart failure patients with atrial fibrillation.|
|Jump to Full Text|
|PMID: 19861396 Owner: NLM Status: MEDLINE|
|Cardiac resynchronization therapy (CRT) is an important device-based, non-pharmacological approach that has shown, in large randomized trials, to improve left ventricular (LV) function and reduce both morbidity and mortality rates in selected patients affected by advanced heart failure (HF): New York Heart Association (NYHA) functional class III-IV, reduced LV systolic function with an ejection fraction (EF) <or=35%, QRS duration >or=120 ms, on optimal medical therapy, and who were in sinus rhythm. For the first time, the latest ESC and AHA/ACC/HRS Guidelines have considered atrial fibrillation (AF) patients, who constitute an important subgroup of HF patients, as eligible to receive CRT. Nevertheless, these Guidelines did not include a strategy for defining differentiated approaches according to AF duration or burden. In this review, the authors explain in which way AF may interfere with adequate CRT delivery, how to manage different AF burden, and finally present a brief overview on the effects of CRT in AF patients.|
|Maurizio Gasparini; François Regoli; Paola Galimberti; Carlo Ceriotti; Alessio Cappelleri|
Related Documents :
|22581166 - Risk stratification and timing of revascularization: which patients benefit from early ...
14575626 - Contemporary medical, surgical, and device therapies for end-stage heart failure.
17461866 - Evidence for electrical remodeling of the native conduction system with cardiac resynch...
18091646 - A review of factors contributing to health related quality of life achieved with cardia...
23562116 - Role of echocardiography in takotsubo cardiomyopathy.
7748046 - Antiarrhythmic drug prescription in patients after myocardial infarction in the last de...
|Type: Journal Article; Research Support, Non-U.S. Gov't; Review|
|Title: Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology Volume: 11 Suppl 5 ISSN: 1532-2092 ISO Abbreviation: Europace Publication Date: 2009 Nov|
|Created Date: 2009-10-28 Completed Date: 2010-02-02 Revised Date: 2010-09-28|
Medline Journal Info:
|Nlm Unique ID: 100883649 Medline TA: Europace Country: England|
|Languages: eng Pagination: v82-6 Citation Subset: IM|
|IRCCS Istituto Clinico Humanitas, Via Manzoni 56, Rozzano/Milano, Italy. email@example.com|
|APA/MLA Format Download EndNote Download BibTex|
Cardiac Pacing, Artificial / methods*
Heart Failure / physiopathology, therapy*
Journal ID (nlm-ta): Europace
Journal ID (publisher-id): europace
Journal ID (hwp): europace
Publisher: Oxford University Press
Published on behalf of the European Society of Cardiology. All rights reserved. ? The Author 2009. For permissions please email: firstname.lastname@example.org.
Print publication date: Month: 11 Year: 2009
pmc-release publication date: Month: 11 Year: 2009
Volume: 11 Issue: suppl_5
First Page: v82 Last Page: v86
PubMed Id: 19861396
Publisher Id: eup273
|Cardiac resynchronization therapy in heart failure patients with atrial fibrillation|
1IRCCS Istituto Clinico Humanitas, Via Manzoni 56, Rozzano/Milano, Italy
2Division of Cardiology, Cardiocentro Ticino, Lugano, Switzerland
|*Corresponding author. Tel: +39 02 8224 4622, Fax: +39 02 8224 4693, Email: email@example.com
Cardiac resynchronization therapy (CRT) is an important device-based, non-pharmacological approach that has shown to improve the outcome in selected patients with chronic heart failure (HF). Large randomized trials have demonstrated that CRT improves left ventricular (LV) function and reduces both morbidity and mortality rates.1?5 Until recently, CRT was indicated in patients with advanced HF [New York Heart Association (NYHA) functional class III?IV], reduced LV systolic function [ejection fraction (EF) ?35%], evidence of electrical dyssynchrony (QRS duration ?120 ms), receiving optimal medical therapy, and who were in sinus rhythm (SR).6 In the last ESC recommendations,7 for the first time, atrial fibrillation (AF) patients, who constitute an important subgroup of HF patients treated with CRT,8 have been considered as eligible to receive CRT on the condition that the effects of underlying rhythm be neutralized by atrio-ventricular junction (AVJ) ablation. The AHA/ACC/HRS Guidelines9 also favourably considered CRT in HF patients with AF, without however emphasizing the possible need for aggressive rate control. Also, these Guidelines remain imprecise in defining differentiated approaches according to the forms of AF other than permanent. The present review explains, in the first instance, in which way AF interferes with adequate CRT. Secondly, a brief overview on the effects of CRT in AF patients is presented, followed by some recommendations, based on current evidence, on the most adequate approach according to patient characteristics, emphasizing the extent of atrial arrhythmic [atrial tachycardia (AT)/AF] burden. It is important to point out that these recommendations remain unsupported by evidence derived from randomized controlled trials (RCTs), which are much needed.10
Atrial fibrillation (whether permanent, persistent, or paroxysmal) poses a number of challenges for adequate CRT delivery. An intrinsic, intermediate-to-high, irregular spontaneous AF rhythm reduces the percentage of effectively biventricular paced captured beats (BVP%). Even in a patient who has normal rate AF, phases of effective biventricular capture alternate with phases of competing AF rhythm which causes spontaneous, fusion, or pseudo-fusion beats (Figure?1). This suggests that the global effective ?CRT-dose? may be markedly reduced compared with atrial-synchronous rhythm with a short AV interval (as is achieved during SR) since the number of effective biventricular captured beats are reduced. Moreover, in AF patients, during exertion, spontaneous ventricular rate tends to override BVP rates, determining a further reduction of paced beats precisely when patients are most in need of having biventricular capture, thus greatly limiting functional capacity. Another problem is the possible negative impact on prognosis of using combinations of negative chronotropic therapy to achieve adequate rate control. In fact, some studies have ?indirectly? suggested that the use of either digoxin or amiodarone in HF may increase morbidity and mortality.4
Adequate management of AF and other atrial arrhythmias is primarily based on defining the AT/AF burden and how it impacts negatively on CRT delivery.
Defining atrial arrhythmic burden is derived from integrating clinical, device-derived data, as well as instrumental findings (such as echocardiographic measures). Any HF patient with a history of atrial arrhythmias requires particular attention, especially in the first months of CRT, in order to ensure that resynchronization be adequately delivered.
From a clinical standpoint, it is important to identify symptoms such as palpitations, and more importantly, worsening effort dyspnoea which may suggest that the resynchronization effect is reduced because of the interference of the underlying atrial rhythm. These clinical aspects should be substantiated by instrumental echocardiographic data, which may show unchanged or further progression of LV dysfunction expressed through increased ventricular volumes and further EF reduction. Retrieving relevant information (BVP%, duration, and numbers of ?mode switch? episodes, etc.) through device monitoring (Figure?2) may complement clinical and echocardiographic data and, thus, provide a more complete picture on the extent of AF/AT burden in each patient. These different aspects, all obtainable during a routine outpatient visit, allow provision of an approximation of the effective AF/AT burden influencing CRT delivery. Atrial tachycardia/AF burden may be considered high, intermediate, or low. Recently, Kamath11 pointed out the importance of an accurate evaluation of CRT-dose using sophisticated 12-lead Holter monitoring, which seemed to be more accurate than conventional device-based information.
Rate control strategy encompasses treatment options which effectively reduce and regularize heart rate in patients who usually have permanent AF or a persistent AF which cannot be readily cardioverted to SR. The rate control strategy embodies two aspects which act favourably on cardiac mechanics. First, lowering heart rate to intermediate-to-low rate allows better diastolic filling and increases stroke volume in hearts with conserved Frank?Starling mechanism. Secondly, the regularization of heart rate further reinforces favourable effects on diastolic function.12 The recourse to rate control drugs and/or activation of device-based algorithms is reasonable as first-line approach when AF/AT burden is low/intermediate.
Rate control drugs considered effective in HF patients with depressed LV function include digoxin, amiodarone, and beta-blockers. However, more recent findings derived from randomized trials have suggested caution in the use of digoxin and amiodarone in patients with HF.13
Some device-derived features may be helpful to improve rate control and thus improve CRT delivery. These features include ventricular rate regularization (VRR) which consists in performing BVP, which ?overrides? intrinsic rhythm, through faster ventricular-paced depolarization allowing to reduce short cycles through retrograde concealed penetration of the AV node.14,15 The benefits of rate control achieved by activating VRR function is well established in patients with chronic AF and no or only mild HF treated with a single chamber right ventricular (RV) pacing. In these patients, VRR has been demonstrated to confer acute haemodynamic benefits,16 to restore autonomic balance,17 and to provide a more regular rhythm during exercise,14 thus potentially improving functional status.
Another useful feature is ?ventricular sense response? (also called ?trigger? function) which triggers LV pacing after a premature RV sense event is detected:17 this option may be activated in all CRT devices of the latest generation.
In the context of CRT, the effectiveness of such rate control and rate regularization algorithms combined with the use of rate control drugs has not been investigated in an RCT. Findings derived from different large observational cohort studies on the effects of CRT in patients with permanent AF have yielded contrasting results. One of these studies18 observed that treatment combining negative chronotropic drugs and activation of device features (VRR and trigger mode), even if permitting 85% of biventricular stimulation, did not yield significant long-term improvements in functional status, LVEF, or LV end-systolic volume (LVESV) reduction. The ineffectiveness of this approach further found confirmation through another more extensive multicentre European study, which reported relatively high death rate, particularly occurring for worsening progressive HF in AF patients treated with negative chronotropic drugs.19 Quite differently, other smaller studies have advocated20 that to achieve good results after CRT in terms of survival, aggressive rate control strategy is not necessary. It is worth emphasizing, however, that when the survival curves of the HF patients with AF treated with a combined device-based/drug regimen are compared,21 yearly death rate for any cause is considered to be remarkably high, amounting to over 14%/year in both separate cohorts of non-ablated patients (Figure?3).
It therefore follows that in HF patients treated with CRT who present a high or intermediate AT/AF burden, the pursuit of an aggressive treatment strategy, such as AVJ ablation, is warranted.
Atrio-ventricular junction ablation is commonly performed in patients with symptomatic, drug-refractory, fast, permanent AF as part of the conventional ?ablate and pace? strategy, and has been shown to confer symptomatic relief.22?24 Atrio-ventricular junction ablation in individuals with AF treated with CRT has mainly been confined to selected patients in whom high-rate AF or AT jeopardizes satisfactory biventricular stimulation, and in CRT-implantable cardioverter defibrillator (ICD) recipients determines inappropriate ICD interventions.25 The problem of inappropriate ICD therapies during AF, constituting ?30% of all ICD interventions,25 has an important negative impact on the quality of life of patients and may be completely resolved after AVJ ablation. However, in the context of CRT in HF patients with concomitant AF, a growing amount of evidence has demonstrated that AVJ ablation may be useful to optimize CRT delivery by eliminating the deleterious haemodynamic effects of a competing, irregular, spontaneous intrinsic rhythm. The MUSTIC AF randomized trial,26 besides being the first randomized trial demonstrating possible benefits of CRT in HF patients with permanent AF and conventional indication for CRT, also showed that in these patients, the preferred mode of ventricular stimulation was biventricular as opposed to RV. The study enrolled AF patients with either slow-rate AF or those who underwent ablation of the AV node; the effects between pacing modes were compared using a crossover design with two 3-month periods. Although no result was found in the intention-to-treat analysis between the two modes (because of high numbers of dropouts), HF patients who completed the study improved in terms of functional status26 with BVP. These effects were maintained after 1 year for most patients.27
Two other prospective studies investigated the effects of pacing mode in the management of AF with rapid ventricular rates following AVJ ablation. The OPSITE trial28 showed that ?rate control? achieved following AVJ ablation significantly improved symptoms and functional status with no difference between the pacing modalities, whether LV or RV, but in a population with much better LV function. The PAVE29 trial further confirmed the benefits of the ?ablate and pace? approach using different pacing modes. The latter study observed a greater benefit of the BVP mode in patients with depressed LVEF (?45%) and/or in NYHA functional class III.
Further observational studies have investigated the acute and short-term effects of AVJ ablation in HF patients with AF treated with CRT and have demonstrated an increase in global LV function, a reduction of mitral regurgitation, and an increase in exercise capacity;30?32 others have confirmed the chronic effects of CRT in this patient subgroup, reporting improvements in NYHA class, exercise capacity, and global LV function.18,26,27,33,34 It is important to stress that these benefits appear to be confined to AF patients with previous AVJ ablation or spontaneous low-rate AF.
One large observational prospective investigation18 specifically evaluated the effects of AVJ ablation on CRT delivery using a pre-defined protocol. This study showed that only those AF patients who underwent AVJ ablation (and thus approaching 100% effective BVP) showed significant improvements in LVEF, LVESV, and exercise capacity. Furthermore, a significantly higher proportion of responders (response defined as a ?10% reduction in LVESV) were observed in the AVJ ablation group (68%) compared with the non-ablated group (18%) at 12 months. As later observed by the same groups in a more extensive observational multicentre study, CRT combined with AVJ ablation conferred a significant reduction of deaths for any cause compared with CRT alone, particularly by reducing deaths for progressive HF.
Taken together, based on current observational data on AF populations treated with CRT, the benefits of AVJ ablation in allowing appropriate CRT delivery seem to outweigh the risks associated with creating pacemaker dependency. The peculiarity of CRT devices (using an RV and an LV pacing leads) should, theoretically, at least reduce the risks of pacemaker dependency related to lead fractures or malfunction. Nonetheless, the fear of pacemaker dependency remains a limiting aspect for the wider diffusion of AVJ ablation.
Further studies are of course needed10 to investigate the extensive benefits of adding AVJ ablation to CRT in HF patients with AF following a prospective, randomized, multicentre design. The AVERT-AF35 (Atrio-Ventricular Junction Ablation Followed by Resynchronization Therapy in patients with CHF and AF) and the An-Art study36 (AV node ablation in CRT) are both concerned with establishing whether AVJ ablation coupled with BVP may significantly improve functional capacity compared with pharmacological therapy in HF patients with permanent AF and depressed EF. It should be stated that such studies aiming to assess the effects of CRT according to soft/subjective endpoints may add little to the current recommendations. There is a great need to design RCTs with strong endpoints, even though such designs may be difficult to implement for ethical and financial reasons. A reasonable and ?up-dated? approach to investigate the effects of CRT in this group involves using device-based surrogates of major clinical events. Device-based remote continuous patient monitoring may provide information on a daily basis of the patients' functional and clinical status, before the onset of an overt clinical event becomes manifest.37,38 But before these parameters may be validated as surrogates for strong endpoints of major cardiovascular events, better definition of their accuracy is needed.
Atrial fibrillation and other atrial rhythm disturbances in patients with HF may have an important negative impact on the clinical benefit conveyed by CRT, if these are not appropriately managed. Careful overall evaluation is mandatory to define precisely the AT/AF burden in order to articulate tailored diagnostic and therapeutic strategies. On the basis of recent observational data, in patients presenting intermediate or elevated AT/AF burden, AVJ ablation may represent a fundamental tool to achieve full CRT delivery and, thus, confer marked improvements in global cardiac function, and, further, in survival. More studies are necessary to further support the recourse to AVJ ablation in this situation. Efforts should also be dedicated towards establishing tailored treatment approaches to adequately manage different atrial rhythm issues in HF patients treated with CRT.
Conflict of interest: none declared.
Funding to pay the Open Access publication charges for this article was provided by Electrophysiology and Pacing Unit, IRCCS Istituto Clinico Humanitas, Rozzano, Milano.
|1.||Cazeau S,Leclercq C,Lavergne T,Walker S,Varma C,Garrigue S,et al. Effects of multisite biventricular pacing in patients with heart failure and intraventricular conduction delayN Engl J MedYear: 20013448738011259720|
|2.||Abraham WT,Fisher WG,Smith AL,Delurgio DB,Leon AR,Loh E,et al. Cardiac resynchronization in chronic heart failureN Engl J MedYear: 200234618455312063368|
|3.||Auricchio A,Stellbrink C,Sack S,Block M,Vogt J,Bakker P,et al. Long-term clinical effect of hemodynamically optimized cardiac resynchronization therapy in patients with heart failure and ventricular conduction delayJ Am Coll CardiolYear: 20023920263312084604|
|4.||Bristow MR,Saxon LA,Boehmer J,Krueger S,Kass DA,De Marco T,et al. Cardiac-resynchronization therapy with or without an implantable defibrillator in advanced chronic heart failureN Engl J MedYear: 200435021405015152059|
|5.||Cleland JGF,Daubert JC,Erdmann E,Freemantle N,Gras D,Kappenberger L,et al. The effect of cardiac resynchronization on morbidity and mortality in heart failureN Engl J MedYear: 200535215394915753115|
|6.||Swedberg K,Cleland JGF,Dargie H,Drexler H,Follath F,Komajda M,et al. Guidelines for the diagnosis and treatment of chronic heart failure: executive summary (update 2005): the Task Force for the diagnosis and treatment of chronic heart failure of the European Society of CardiologyEur Heart JYear: 20052611154015901669|
|7.||Vardas PE,Auricchio A,Blanc JJ,Daubert JC,Drexler H,Ector H,et al. Guidelines for cardiac pacing and cardiac resynchronization therapy: the Task Force for cardiac pacing and cardiac resynchronization therapy of the European Society of Cardiology. Developed in collaboration with the European Heart Rhythm AssociationEur Heart JYear: 20072822569517726042|
|8.||Auricchio A,Metra M,Gasparini M,Lamp B,Klersy C,Curnis A,et al. Long-term survival of patients with heart failure and ventricular conduction delay treated with cardiac resynchronization therapyAm J CardiolYear: 200799232817223424|
|9.||Epstein AE,DiMarco JP,Ellenbogen KA,Estes NA,Freedman RA,Gettes LS,et al. ACC/AHA/HRS 2008 Guidelines for device-based therapy of cardiac rhythm abnormalities: a report of the American College of Cardiology/American Heart Association Task Force on practice guidelines (Writing committee to revise the ACC/AHA/NASPE 2002 Guideline update for implantation of cardiac pacemakers and antiarrhythmia devices): developed in collaboration with the American Association for Thoracic Surgery and Society of Thoracic SurgeonsCirculationYear: 2008117e35040818483207|
|10.||Steinberg JS. Desperately seeking a randomized clinical trial of resynchronization therapy for patients with heart failure and atrial fibrillationJ Am Coll CardiolYear: 200648744616904543|
|11.||Kamath GS,Cotiga D,Koneru JN,Arshad A,Pierce W,Aziz E,et al. The utility of 12-lead Holter monitoring in patients with permanent atrial fibrillation for the identification of non-responders following cardiac resynchronization therapyJ Am Coll CardiolYear: 2009531050519298918|
|12.||Ueng KC,Tsai TP,Tsai CF,Wu DJ,Lin CS,Lee SH,et al. Acute and long-term effects of atrioventricular junction ablation and VVIR pacemaker in symptomatic patients with chronic lone atrial fibrillation and normal ventricular responseJ Cardiovasc ElectrophysiolYear: 200112303911291803|
|13.||Bardy GH,Lee KL,Mark DB,Poole JE,Packer DL,Boineau R,et al. Amiodarone or an implantable cardioverter-defibrillator for congestive heart failureN Engl J MedYear: 20053522253715659722|
|14.||Lau CP,Jiang ZY,Tang MO. Efficacy of ventricular rate stabilization by right ventricular pacing during atrial fibrillationPacing Clin ElectrophysiolYear: 19982154289558685|
|15.||Simpson CS,Yee R,Lee JK,Braney M,Klein GJ,Krahn AD,et al. Safety and feasibility of a novel rate-smoothed ventricular pacing algorithm for atrial fibrillationAm Heart JYear: 200114229430011479469|
|16.||Kerr AJ,Williams MJA,Stewart RAH. Ventricular rate and beat-to-beat variation of stroke volume in atrial fibrillationAm J CardiolYear: 2001871116911348616|
|17.||Ciaramitaro C,Sgarito G,Solimene F,Maglia G,Vicentini A,Di Donato G,et al. Role of rate control and regularization through pacing in patients with chronic atrial fibrillation and preserved ventricular function: The VRR studyPacing Clin ElectrophysiolYear: 2006298667416923003|
|18.||Gasparini M,Auricchio A,Regoli F,Fantoni C,Kawabata M,Galimberti P,et al. Four-year efficacy of cardiac resynchronization therapy on exercise tolerance and disease progression: the importance of performing atrioventricular junction ablation in patients with atrial fibrillationJ Am Coll CardiolYear: 2006487344316904542|
|19.||Gasparini M,Auricchio A,Metra M,Regoli F,Fantoni C,Lamp B,et al. Long-term survival in patients undergoing cardiac resynchronization therapy: the importance of performing atrio-ventricular junction ablation in patients with permanent atrial fibrillationEur Heart JYear: 20082916445218390869|
|20.||Khadjooi K,Foley PW,Chalil S,Anthony J,Smith REA,Frenneaux MP,et al. Long-term effects of cardiac resynchronisation therapy in patients with atrial fibrillationHeartYear: 2008948798318208826|
|21.||Gasparini M,Regoli F. Cardiac resynchronisation therapy in patients with atrial fibrillationHeartYear: 20099583 author reply 83?4. 19047444|
|22.||Brignole M,Menozzi C,Gianfranchi L,Musso G,Mureddu R,Bottoni N,et al. Assessment of atrioventricular junction ablation and VVIR pacemaker versus pharmacological treatment in patients with heart failure and chronic atrial fibrillation: a randomized, controlled studyCirculationYear: 199898953609737514|
|23.||Natale A,Zimerman L,Tomassoni G,Newby K,Leonelli F,Fanelli R,et al. AV node ablation and pacemaker implantation after withdrawal of effective rate-control medications for chronic atrial fibrillation: effect on quality of life and exercise performancePacing Clin ElectrophysiolYear: 1999221634910598967|
|24.||Ozcan C,Jahangir A,Friedman PA,Patel PJ,Munger TM,Rea RF,et al. Long-term survival after ablation of the atrioventricular node and implantation of a permanent pacemaker in patients with atrial fibrillationN Engl J MedYear: 200134410435111287974|
|25.||Sweeney MO,Wathen MS,Volosin K,Abdalla I,DeGroot PJ,Otterness MF,et al. Appropriate and inappropriate ventricular therapies, quality of life, and mortality among primary and secondary prevention implantable cardioverter defibrillator patients: results from the pacing fast VT reduces shock therapies (PainFREE Rx II) trialCirculationYear: 2005111289890515927965|
|26.||Leclercq C,Walker S,Linde C,Clementy J,Marshall AJ,Ritter P,et al. Comparative effects of permanent biventricular and right-univentricular pacing in heart failure patients with chronic atrial fibrillationEur Heart JYear: 2002231780712419298|
|27.||Linde C,Leclercq C,Rex S,Garrigue S,Lavergne T,Cazeau S,et al. Long-term benefits of biventricular pacing in congestive heart failure: results from the MUltisite STimulation in cardiomyopathy (MUSTIC) studyJ Am Coll CardiolYear: 200240111812103264|
|28.||Brignole M,Gammage M,Puggioni E,Alboni P,Raviele A,Sutton R,et al. Comparative assessment of right, left, and biventricular pacing in patients with permanent atrial fibrillationEur Heart JYear: 2005267122215618036|
|29.||Doshi RN,Daoud EG,Fellows C,Turk K,Duran A,Hamdan MH,et al. Left ventricular-based cardiac stimulation post AV nodal ablation evaluation (The PAVE study)J Cardiovasc ElectrophysiolYear: 2005161160516302897|
|30.||Garrigue S,Bordachar P,Reuter S,Ja?s P,Ha?ssaguerre M,Clementy J. Comparison of permanent left ventricular and biventricular pacing in patients with heart failure and chronic atrial fibrillation: a prospective hemodynamic studyCard Electrophysiol RevYear: 200373152415071245|
|31.||Puggioni E,Brignole M,Gammage M,Soldati E,Bongiorni MG,Simantirakis EN,et al. Acute comparative effect of right and left ventricular pacing in patients with permanent atrial fibrillationJ Am Coll CardiolYear: 200443234814736442|
|32.||Hay I,Melenovsky V,Fetics BJ,Judge DP,Kramer A,Spinelli J,et al. Short-term effects of right-left heart sequential cardiac resynchronization in patients with heart failure, chronic atrial fibrillation, and atrioventricular nodal blockCirculationYear: 200411034041015557370|
|33.||Leon AR,Greenberg JM,Kanuru N,Baker CM,Mera FV,Smith AL,et al. Cardiac resynchronization in patients with congestive heart failure and chronic atrial fibrillation: effect of upgrading to biventricular pacing after chronic right ventricular pacingJ Am Coll CardiolYear: 20023912586311955841|
|34.||Molhoek SG,Bax JJ,Bleeker GB,Boersma E,van Erven L,Steendijk P,et al. Comparison of response to cardiac resynchronization therapy in patients with sinus rhythm versus chronic atrial fibrillationAm J CardiolYear: 2004941506915589005|
|35.||Hamdan MH,Freedman RA,Gilbert EM,DiMArco JP,Ellenbogen KA,Page RL. Atrioventricular junction ablation followed by resynchronization therapy in patients with congestive heart failure and atrial fibrillation (AVERT-AF) study designPacing Clin ElectrophysiolYear: 2006291081817038140|
|36.||Sticherling C. Atrioventricular (AV) node ablation in cardiac resynchronization therapy www.clinicaltrial.gov/ct2/results?term=Atrioventricular+%28AV%29+node+ablation+in+cardiac+resynchronization+therapy.|
|37.||Kawabata M,Fantoni C,Regoli F,Raffa S,Pastori F,Fratini S,et al. Activity monitoring in heart failure patients with cardiac resynchronization therapyCirc JYear: 20077118859218037741|
|38.||Ypenburg C,Bax JJ,Van der Wall EE,Schalij MJ,Van Erven L. Intrathoracic impedance monitoring to predict decompensated heart failureAm J CardiolYear: 200799554717293202|
[Figure ID: EUP273F1]
A patient with AF and HF treated with CRT, spontaneous irregular intrinsic beats alternate with fusion and pseudo-fusion beats, thus markedly reducing effective CRT. As shown in the figure, this may occur even during normal rate AF.
[Figure ID: EUP273F2]
Different aspects of CRT patients with AF before and after AVJ ablation, which may be appreciated through device features. In a 59-year-old female with permanent AF treated with a CRT-D device, AVJ ablation yielded the following improvements: better functional status as shown by the number of hours of activity per day; maximization of BVP%; and improvement of heart rate variability profile.
[Figure ID: EUP273F3]
Comparison of Kaplan?Meier analysis for freedom from death for any cause between the Gasparini et al.19 and the Khadjooi et al.20 studies. The figure?is adapted from Gasparini et al.19 and Khadjooi et al.20 SR, sinus rhythm; AF, atrial fibrillation; AF-drugs: atrial fibrillation with preserved AV node conduction; AF-abl, atrial fibrillation group with ablated AV node.
Keywords: Atrial fibrillation, Heart failure, Resynchronization, Defibrillators, Ablation.
Previous Document: Biventricular pacing in paced patients with normal hearts.
Next Document: Cardiac resynchronization therapy in combination with implantable cardioverter-defibrillator.