Cardiac electrophysiology review最新文献

{"title":"Atrial pacing therapies for prevention of atrial fibrillation in patients with implantable defibrillators.","authors":"Anne M Gillis","doi":"10.1023/B:CEPR.0000023135.19859.6d","DOIUrl":"https://doi.org/10.1023/B:CEPR.0000023135.19859.6d","url":null,"abstract":"<p><p>Atrial fibrillation (AF), atrial flutter and atrial tachycardia (AT) occur frequently in patients following implantation of an implantable cardioverter defibrillator (ICD) for the treatment of ventricular tachyarrhythmias. Some new generation ICDs have incorporated atrial antitachycardia pacing therapy (ATP) and atrial pacing algorithms designed specifically for the prevention of AF. In the GEM III AT clinical evaluation, atrial ATP efficacy for termination of AF and AT was assessed. Overall ATP efficacy for AF/AT, based on device classification, was 40% when adjusted using the Generalized Estimating Equations to account for correlated data that arises from utilizing multiple episodes in some patients. However, many episodes of AF/AT were noted to terminate within 10 minutes of onset. Applying a more conservative definition of efficacy, termination within 20 sec of delivery of the last atrial ATP, efficacy for termination of AF/AT was 26%. 50 Hz burst pacing was shown to have minimal efficacy for termination of AF and modest incremental benefit following ramp or burst pacing therapies for AT. These observations provide a more realistic expectation of the value of atrial ATP in the ICD population with AF. Atrial ATP terminates some episodes of AT but previously reported efficacy rates of 40-50% are exaggerated and in part reflect spontaneous terminations of some AF/AT episodes.</p>","PeriodicalId":80888,"journal":{"name":"Cardiac electrophysiology review","volume":"7 4","pages":"345-7"},"PeriodicalIF":0.0,"publicationDate":"2003-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1023/B:CEPR.0000023135.19859.6d","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"24457687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Is Bachmann's Bundle the only right site for single-site pacing to prevent atrial fibrillation? Results of a multicenter randomized trial.","authors":"Steven J Bailin","doi":"10.1023/B:CEPR.0000023131.13609.ab","DOIUrl":"https://doi.org/10.1023/B:CEPR.0000023131.13609.ab","url":null,"abstract":"<p><p>The site of atrial pacing influences atrial activation patterns. It is believed that disparities in atrial activation and repolarization are contributors to the development and recurrence of atrial arrhythmias. We hypothesized that pacing from Bachmann's Bundle would improve clinical outcomes in patients with paroxysmal atrial fibrillation compared to right atrial appendage pacing. Pacing from Bachmann's Bundle results in a significant reduction in P wave duration and improvement in biatrial activation symmetry compared to right atrial appendage pacing. Compared to right atrial appendage pacing, Bachmann's bundle pacing improves sinus rhythm (75% vs. 47% at two years, p < 0.01) in patients with a history of paroxysmal atrial fibrillation. Recent studies have confirmed the benefits of Bachmann's Bundle pacing on atrial activation and rhythm regulation. Thus, Bachman's Bundle should be considered the preferred site for atrial pacing in patients with a history of paroxysmal atrial fibrillation.</p>","PeriodicalId":80888,"journal":{"name":"Cardiac electrophysiology review","volume":"7 4","pages":"325-8"},"PeriodicalIF":0.0,"publicationDate":"2003-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1023/B:CEPR.0000023131.13609.ab","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"24458407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Role of beta-blocker therapy in heart failure and atrial fibrillation.","authors":"Jeffrey W H Fung,&nbsp;Cheuk M Yu,&nbsp;Leo C C Kum,&nbsp;Gabriel W K Yip,&nbsp;John E Sanderson","doi":"10.1023/B:CEPR.0000012390.43937.2c","DOIUrl":"https://doi.org/10.1023/B:CEPR.0000012390.43937.2c","url":null,"abstract":"<p><p>Heart failure is a serious disorder associated with substantial morbidity and mortality. Approximately 15-30% patients with systolic heart failure are in atrial fibrillation and the proportion increases with severity of heart failure. Patients with heart failure and atrial fibrillation have worse outcome than those in sinus rhythm. Beta-blockers, together with angiotensin-converting enzymes inhibitors, are the standard therapy in patients with chronic heart failure. Retrospective studies have suggested that despite the improvement in left ventricular systolic function after treatment with beta-blockers, the exercise capacity and symptoms in those heart failure patients with atrial fibrillation was not improved as much as those in sinus rhythm. Moreover, the use of bisoprolol in the Cardiac Insufficiency Bisoprolol Study II, unlike those in sinus rhythm, failed to produce any survival benefit in patients with poor systolic function and atrial fibrillation. It seems that those patients with heart failure and atrial fibrillation may have different response to beta-blocker therapy. Prospective trials to clarify the impact of beta-blocker therapy and the optimal therapeutic strategy in this high-risk group of patients are warranted.</p>","PeriodicalId":80888,"journal":{"name":"Cardiac electrophysiology review","volume":"7 3","pages":"236-42"},"PeriodicalIF":0.0,"publicationDate":"2003-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1023/B:CEPR.0000012390.43937.2c","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"24177914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Significance of atrial fibrillation during acute myocardial infarction, and its current management: insights from the GUSTO-3 trial.","authors":"Cheuk-Kit Wong,&nbsp;Harvey D White,&nbsp;Robert G Wilcox,&nbsp;Douglas A Criger,&nbsp;Robert M Califf,&nbsp;Eric J Topol,&nbsp;E Magnus Ohman","doi":"10.1023/B:CEPR.0000012382.81986.47","DOIUrl":"https://doi.org/10.1023/B:CEPR.0000012382.81986.47","url":null,"abstract":"<p><p>The Global Use of Strategies to Open Occluded Coronary Arteries (GUSTO)-3 atrial fibrillation (AF) substudy assessed the prognostic significance of AF during acute myocardial infarction (AMI), the use of antiarrhythmic therapies, and whether different antiarrhythmic therapies were associated with different outcomes. The timing of the onset of AF relative to other post-AMI complications was recorded in the study. Of the 13,858 patients who were in sinus rhythm at the time of enrolment into GUSTO-3, 906 (6.5%) developed AF and 12,952 did not. Worsening heart failure, hypotension, third-degree heart block, and ventricular fibrillation were independent predictors of new-onset AF. The risks of 30-day and 1-year mortality were increased among patients with AF versus patients without AF before (odds ratio [OR] 2.74, 95% confidence interval [CI] 2.56-3.34; and OR 2.93, 95% CI 2.48-3.46, respectively) and after adjustment for baseline factors and pre-AF complications (OR 1.49, 95% CI 1.17-1.89; and OR 1.64, 95% CI 1.35-2.01, respectively). A total of 1,138 patients had data available on the management of their AF, including 117 with a history of paroxysmal AF and 138 with chronic AF prior to AMI. Of these 1,138 patients, 317 (28%) received antiarrhythmic therapies: class I antiarrhythmic drugs in 12%, sotalol in 5% and amiodarone in 15%. Electrical cardioversion was attempted in 116 patients (10%). Sinus rhythm was restored in 72% of patients given class I drugs, 67% of those given sotalol, 79% of those given amiodarone, and 64% of those who underwent electrical cardioversion. After adjustment for baseline characteristics and pre-AF complications, none of the specific antiarrhythmic therapies was associated with a higher chance of having sinus rhythm at discharge or before deterioration to in-hospital death. However, the use of class I antiarrhythmic drugs or sotalol was associated with lower unadjusted 30-day and 1-year mortality rates. After adjustment for baseline factors and pre-AF complications, the ORs for 30-day and 1-year mortality were 0.42 (95% CI 0.19-0.89) and 0.58 (95% CI 0.33-1.04), respectively, with class I agents, and 0.31 (95% CI 0.07-1.32) and 0.31 (95% CI 0.09-1.02), respectively, with sotalol. In contrast, there was no association between the use of amiodarone or electrical cardioversion and 30-day or 1-year mortality. New AF is often secondary to other post-AMI complications, but is in itself an independent predictor of a worse outcome. Clinical management of AF is variable, but in GUSTO-3 there was a strong trend towards lower mortality associated with the use of class I antiarrhythmic agents or sotalol. Randomized trials are needed to investigate this observation further.</p>","PeriodicalId":80888,"journal":{"name":"Cardiac electrophysiology review","volume":"7 3","pages":"201-7"},"PeriodicalIF":0.0,"publicationDate":"2003-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1023/B:CEPR.0000012382.81986.47","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"24177464","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of electrode position on the outcome of cardioversion.","authors":"Paulus Kirchhof,&nbsp;Martin Borggrefe,&nbsp;Günter Breithardt","doi":"10.1023/B:CEPR.0000012399.96959.ab","DOIUrl":"https://doi.org/10.1023/B:CEPR.0000012399.96959.ab","url":null,"abstract":"<p><p>Acute termination of atrial fibrillation is the starting point of any therapy aimed at preventing atrial fibrillation and improves cardiac output in patients with hemodynamic compromise due to the arrhythmia. External electrical cardioversion is a simple procedure to terminate persistent atrial fibrillation in the majority of cases. Initially, Lown et al. used an anterior-lateral position of electrodes to apply a cardioversion shock. Recent pathophysiological studies have shown that atrial fibrillation is maintained by functional re-entry circuits anchored in the left atrium. As the left atrium is located posteriorly in the thorax, an anterior-posterior electrode position may be more efficient for external cardioversion of atrial fibrillation than the commonly used anterior-lateral electrode position. Several recent studies have confirmed that an anterior-posterior electrode position is superior to an anterior-lateral electrode position for external cardioversion of atrial fibrillation. There are no indications that an anterior-posterior electrode position is less safe than an anterior-lateral electrode position. We therefore suggest that an anterior-posterior electrode position should initially be used for external cardioversion of atrial fibrillation.</p>","PeriodicalId":80888,"journal":{"name":"Cardiac electrophysiology review","volume":"7 3","pages":"292-6"},"PeriodicalIF":0.0,"publicationDate":"2003-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1023/B:CEPR.0000012399.96959.ab","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"24177353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Facilitating electrical cardioversion of persistant atrial fibrillation by antiarrhythmic drugs: update on clinical trial results.","authors":"Ruey J Sung","doi":"10.1023/B:CEPR.0000012401.72234.cd","DOIUrl":"https://doi.org/10.1023/B:CEPR.0000012401.72234.cd","url":null,"abstract":"<p><p>Results from clinical trials suggest that antiarrhythmic drugs (AD) can facilitate electrical cardioversion (EC) for persistent atrial fibrillation (AF) (duration >48 hours, no spontaneous termination) by suppression of immediate reinitiation of AF following the procedure. Class IC agents may increase the atrial defibrillation threshold (DFT) by significantly reducing the availability of Na+-channel for depolarization. In contrast, class III agents may decrease the atrial DFT by markedly prolonging atrial refractoriness. Among all AD, ibutilide and amoidarone have been shown to be most effective in enhancing the acute outcome of EC. In patients who are over 65 years of age at high risks of stroke (e.g., atherosclerotic cardiovascular disease, diabetes, hypertension, previous thromboembolism, etc.), the rhythm control strategy offers no survival advantage over the rate control strategy and frequently subjects patients to serious adverse effects of AD therapy. It can not be overemphasized that adequate anticoagulation (INR 2.0-3.0) with warfarin is needed regardless of whichever strategy is chosen unless there are contraindications. On the other hand, in patients who are under 65 years of age without structural heart disease or other risk factors of stroke, rhythm control can be the treatment of choice. Specifically, if a patient has failed EC alone or if the patient has characteristics (e.g., duration of AF >6 months, left atrium >50 mm, etc.) that EC could fail, AD may be given before the procedure to facilitate EC. In the subgroup of patients who are symptomatic with hypertrophic cardiomyopathy and severe diastolic dysfunction requiring maintenance of sinus rhythm to have sufficient ventricular function for optimization of cardiac output, an aggressive approach for rhythm control with amiodarone along with adequate anticoagulation with warfarin should be encouraged.</p>","PeriodicalId":80888,"journal":{"name":"Cardiac electrophysiology review","volume":"7 3","pages":"300-3"},"PeriodicalIF":0.0,"publicationDate":"2003-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1023/B:CEPR.0000012401.72234.cd","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"24177355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Does conversion and prevention of atrial fibrillation enhance survival in patients with left ventricular dysfunction? Evidence from the Danish Investigations of Arrhythmia and Mortality ON Dofetilide/(DIAMOND) study.","authors":"Ole Dyg Pedersen,&nbsp;Bente Brendorp,&nbsp;Hanne Elming,&nbsp;Steen Pehrson,&nbsp;Lars Køber,&nbsp;Christian Torp-Pedersen","doi":"10.1023/B:CEPR.0000012386.82055.81","DOIUrl":"https://doi.org/10.1023/B:CEPR.0000012386.82055.81","url":null,"abstract":"<p><strong>Background: </strong>Atrial fibrillation is a common arrhythmia in patients with left ventricular dysfunction associated with increased morbidity and mortality. The present study investigated the potential of dofetilide to restore and maintain sinus rhythm in patients with left ventricular dysfunction, which might reduce mortality and hospitalizations.</p><p><strong>Methods and results: </strong>In the Danish Investigations of Arrhythmia and Mortality ON Dofetilide (DIAMOND) studies, 506 patients were in atrial fibrillation (AF) or atrial flutter (AFl) at baseline. Over the course of study, cardioversion occurred in 148 (59%) dofetilide- and 86 (34%) placebo-treated patients. In these patients, the probability of maintaining sinus rhythm for 1 year was 79% with dofetilide versus 42% with placebo ( P < 0.001). Dofetilide had no effect on all-cause mortality, but restoration and maintenance of sinusrhythm (independent of study treatment) was associated with a significant reduction in mortality (risk ratio [RR], 0.44; 95% CI, 0.30 to 0.64; P < 0.0001). In addition, dofetilide therapy was associated with a significantly lower risk ratio versus placebo for either all-cause (RR, 0.70; 95% CI, 0.56 to 0.89; P < or = 0.005) or congestive heart failure (RR, 0.69; 95% CI, 0.51 to 0.93; P < or = 0.02) rehospitalization.</p><p><strong>Conclusions: </strong>Dofetilide is safe and increases the probability of obtaining and maintaining sinus rhythm in patients with structural heart disease. The present study suggests that restoration of sinus rhythm--on placebo or dofetilide--is associated with improved survival.</p>","PeriodicalId":80888,"journal":{"name":"Cardiac electrophysiology review","volume":"7 3","pages":"220-4"},"PeriodicalIF":0.0,"publicationDate":"2003-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1023/B:CEPR.0000012386.82055.81","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"24177468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Conducting randomized trials in the electrophysiology laboratory: lessons from a randomized comparison of recording methods during pulmonary vein isolation by segmental ostial ablation.","authors":"Hakan Oral,&nbsp;Fred Morady","doi":"10.1023/B:CEPR.0000012392.47852.e8","DOIUrl":"https://doi.org/10.1023/B:CEPR.0000012392.47852.e8","url":null,"abstract":"<p><p>Accurate identification of pulmonary vein (PV) potentials during segmental ostial ablation for PV isolation is very important to completely isolate the PVs and also to avoid unnecessary applications of radiofrequency energy. A prior post hoc analysis of unipolar and bipolar electrograms recorded from successful and unsuccessful ablation sites demonstrated that unipolar electrograms recorded at successful sites were more likely to have a rapid intrinsic deflection, larger amplitude, and earlier activation than electrograms recorded at unsuccessful sites. Moreover, unipolar electrograms recorded from the ablation and circular ostial mapping catheters were almost identical at successful sites. Based on these observations, a prospective, randomized study was conducted to test whether unipolar and bipolar electrograms would facilitate the ablation procedure when compared to bipolar electrograms alone during PV isolation in patients with atrial fibrillation (AF). In 44 consecutive patients with paroxysmal AF, 114 PVs were randomized to segmental ostial ablation guided by unipolar and bipolar electrograms (61) or by bipolar electrograms only (53). Segmental ostial ablation guided by unipolar and bipolar electrograms was associated with a approximately 20-30% decrease in the procedure and fluoroscopy times necessary for isolation of a PV and also in the duration of radiofrequency energy application required for complete isolation of a PV. Although the sample size was not sufficient to detect a 5% change, the success rate for complete electrical isolation and the risk of symptomatic PV stenosis were similar between the 2 groups. Online analysis of unipolar electrograms facilitated the PV isolation procedure and was incremental to the analysis of bipolar electrograms alone. However, because segmental ostial ablation has only modest efficacy in achieving long-term freedom from recurrent AF, alternative ablation strategies that may or may not target PVs will eventually evolve. The role of unipolar electrograms in these new methods remains to be determined.</p>","PeriodicalId":80888,"journal":{"name":"Cardiac electrophysiology review","volume":"7 3","pages":"247-51"},"PeriodicalIF":0.0,"publicationDate":"2003-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1023/B:CEPR.0000012392.47852.e8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"24177916","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Left versus bi-atrial intraoperative saline-irrigated radiofrequency modified maze procedure for atrial fibrillation.","authors":"Mustafa Guden,&nbsp;Belhhan Akpinar,&nbsp;Baris Caynak,&nbsp;Cavlan Turkoglu,&nbsp;Zeki Ozyedek,&nbsp;Ilhan Sanisoglu,&nbsp;Ertan Sagbas,&nbsp;Saide Aytekin,&nbsp;Seher Deniz Oztekin","doi":"10.1023/B:CEPR.0000012393.09666.26","DOIUrl":"https://doi.org/10.1023/B:CEPR.0000012393.09666.26","url":null,"abstract":"<p><strong>Background: </strong>This study was conducted to evaluate the effectiveness of the saline-irrigated radiofrequency modified maze operation for the treatment of chronic atrial fibrillation (AF) and compare the results of the left and bi-atrial procedures.</p><p><strong>Material and method: </strong>During a period of two years, 105 patients with chronic AF having concomitant cardiac surgery underwent the procedure. Patients underwent either a bi-atrial ( n = 48) or left atrial ( n = 57) maze procedure. The first twenty patients underwent a bi-atrial maze procedure regardless of the pathology. In the following patients we adopted the bi-atrial approach in patients with a history of atrial flutter and where the right atrium has to be opened. Otherwise the procedure is restricted to the left atrial side. Mean age was 52 +/- 11 years in bi-atrial group and 54 +/- 9 years in left atrial group.</p><p><strong>Results: </strong>Three patients died early postoperatively (2.9%). There were 4 revisions for bleeding (3.8%). Two patients in bi-atrial group received a permanent pacemaker (4.1%). Patients in both groups were free of AF at the end of the procedure. (Bi-atrial group: sinus: 79.2%, pacemaker: 20.8%), (Left atrial group: sinus: 82.5%, pacemaker: 17.5%) ( p > 0.05). During the last follow-up, sinus rhythm was maintained in 79.6% of cases in bi-atrial group, while this rate was 75.6% in left atrial group ( p > 0.05).</p><p><strong>Conclusion: </strong>Saline irrigated radiofrequency modified maze procedure was performed safely and efficiently. Both the left and bi-atrial procedures were successful in terms of restoring sinus rhythm. Our current policy is to adopt the bi-atrial approach in patients with a history of atrial flutter and where the right atrium has to be opened. Otherwise the procedure is restricted to the left atrial side.</p>","PeriodicalId":80888,"journal":{"name":"Cardiac electrophysiology review","volume":"7 3","pages":"252-8"},"PeriodicalIF":0.0,"publicationDate":"2003-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1023/B:CEPR.0000012393.09666.26","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"24177917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Beta-blocker efficacy according to heart rate and rhythm in patients with heart failure. Commentary on the Cardiac Insufficiency Bisoprolol Study II analysis.","authors":"Philippe P Lechat","doi":"10.1023/B:CEPR.0000012389.01561.27","DOIUrl":"https://doi.org/10.1023/B:CEPR.0000012389.01561.27","url":null,"abstract":"<p><p>Large randomized trials have demonstrated that beta-blocker treatment reduces morbidity and mortality in patients in chronic heart failure. Questions remain about the influence of individual characteristics on the magnitude of the benefit of beta-blockers in patients with heart failure including the influence of heart rate and cardiac rhythm. In the Cardiac Insufficiency Bisoprolol Study II, baseline heart rate and heart rate change over time had prognostic value but treatment with bisoprolol was associated with a benefit at all levels of baseline heart rate and additional benefit related to heart rate slowing was observed. In the subgroup of patients with atrial fibrillation, morbidity and mortality rates were similar in placebo and bisoprolol treated patients. It is possible that patients with atrial fibrillation had a higher level of sympathetic stimulation that would have required higher doses of bisoprolol to achieve a similar level of beta-blockade. Alternatively, the failure to observe improved outcome in the subgroup with atrial fibrillation may have been due to chance. However, because this finding was not observed in other large trials, and because there was no clear explanation, it should not be concluded that patients with chronic heart failure and atrial fibrillation do not benefit from beta-blockade.</p>","PeriodicalId":80888,"journal":{"name":"Cardiac electrophysiology review","volume":"7 3","pages":"233-5"},"PeriodicalIF":0.0,"publicationDate":"2003-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1023/B:CEPR.0000012389.01561.27","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"24177471","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}