Strict Rate Control Research Articles

Impact of Strict and Lenient Heart Rate Control on Six-Minute Walk Test and Quality of Life in Atrial Fibrillation Patients with Rheumatic Mitral Stenosis: A Preliminary Study

Background: Recent studies showed no outcome difference between strict and lenient rate control in the general Atrial Fibrillation (AF) population. However, for AF and Rheumatic Mitral Stenosis (RMS) patients, evidences were lacking. Objective: To assess the impact of strict and lenient heart rate control on the Six-Minute Walk Test (SMWT) and Health Related Quality of Life (HRQoL) in patients with AF and RMS. Material and Methods: A prospective multicenter trial across tertiary hospitals in East Java assessed strict and lenient heart rate control's impact on the SMWT and HRQoL in AF and RMS patients. Sixty-one participants were randomized into strict and lenient groups over six months from March to August 2023. Medications were adjusted to achieve target heart rates, and HRQoL was assessed using SF-36 and SMWT at baseline and three months post-target heart rate attainment. Result: In our study, 29 patients were under strict heart rate control, and 32 were under lenient control. We found a decrease in HRQoL across all subscales, with significant differences observed in general health perception and physical function among those under strict control (p=0.002 and 0.03, respectively). However, no significant disparity was found in the SMWT distance difference between lenient and strict groups (p=0.529), nor in METs (p=0.326). Conclusion: In the study, lenient heart rate control demonstrates significant effects on the general health perception and physical function subscales compared to strict heart rate control. Keyword: Strict and lenient heart rate, HRQoL, Six-Minute Walk Test, Atrial Fibrillation, Rheumatic Mitral Stenosis.

Lenient rate control versus strict rate control for atrial fibrillation: a statistical analysis plan for the Danish Atrial Fibrillation (DanAF) randomized clinical trial

BackgroundA key decision in the treatment of atrial fibrillation is choosing between a rhythm control strategy or a rate control strategy as the main strategy. When choosing rate control, the optimal heart rate target is uncertain. The Danish Atrial Fibrillation trial is a randomized, multicenter, two-group, superiority trial comparing strict rate control versus lenient rate control in patients with either persistent or permanent atrial fibrillation at inclusion. To prevent bias arising from selective reporting and data-driven analyses, we developed a predefined description of the statistical analysis.MethodsThe primary outcome of this trial is the physical component score of the SF-36 questionnaire. A total of 350 participants will be enrolled based on a minimal important difference of 3 points on the physical component score of the SF-36 questionnaire, a standard deviation of 10 points, a statistical power of 80% (beta of 20%), and an acceptable risk of type I error of 5%. All secondary, exploratory, and echocardiographic outcomes will be hypothesis-generating. The analyses of all outcomes will be based on the intention-to-treat principle. We will analyze continuous outcomes using linear regression adjusting for “site,” type of atrial fibrillation at inclusion (persistent/ permanent), left ventricular ejection fraction (≥ 40% or < 40%), and the baseline value of the outcome (all as fixed effects). We define our threshold for statistical significance as a p-value of 0.05 and assessments of clinical significance will be based on the anticipated intervention effects defined in the sample size and power estimations. Thresholds for both statistical and clinical significance will be assessed according to the 5-step procedure proposed by Jakobsen and colleagues.DiscussionThis statistical analysis plan will be published prior to enrolment completion and before any data are available and is sought to increase the validity of the DANish Atrial Fibrillation trial.Trial registrationClinicaltrials.gov NCT04542785. Registered on Sept 09, 2020.

Abstract 12571: Optimal Rate Control Strategy in Patients With Atrial Fibrillation: A Meta-Analysis of Randomized Trials and Multivariable Adjusted Studies

Introduction: Atrial fibrillation (AF) is associated with an increased risk of impaired quality of life, stroke, and mortality. Despite multiple studies, the optimal target for rate control in AF is not definitively known. Methods: We performed a systematic review and meta-analysis comparing the effects of strict rate control (&lt;80 bpm at rest) with a lenient rate control strategy (&lt;110 bpm at rest) in patients with AF. The outcomes analyzed were all-cause mortality, cardiovascular (CV) death and CV hospitalization. A subgroup analysis was also performed in patients with heart failure (HF). PubMed, Scopus and Cochrane Central were searched for randomized controlled trials or observational studies with multivariable analyses adjusting for confounders. Results: Seven studies were included. All studies were either randomized or reported multivariate adjusted hazard ratios. There were 14,154 (59.6%) patients in the strict rate control strategy and 9,606 (40.4%) in the lenient group. AF was reported as paroxysmal in 1,697 (7.3%) patients. All-cause mortality was not statistically different between a strict vs. lenient heart rate control strategy, although there was a tendency towards improvement in the strict control group (HR 1.10; 95% CI 1.00-1.22; p=0.05; Figure 1A). In patients with AF and HF, there was also no significant difference between groups (HR 1.13; 95% CI 0.99-1.30; p=0.08; Figure 1B). Furthermore, CV death (HR 0.91; 95% CI 0.75-1.11) and CV hospitalization (HR 1.01; 95% CI 0.96-1.06) were also not significantly different between the two strategies. Conclusions: There was no significant difference in all-cause mortality between strict and leninent rate control in patients with AF among randomized trials or multivariable adjusted studies. In a subgroup of patients with HF, there was also no significant difference between the two rate control strategies.

Abstract 13075: Hemodynamic Estimation of Personalized Initial Target Heart Rate in Patients With Atrial Fibrillation With Rapid Ventricular Response

Introduction: Rate control in atrial fibrillation (AF) has played a pivot role in clinical setting even though recent advances in rhythm control. There are few evidences for target heart rate in either acute or chronic situations. Hypothesis: This study tried to estimate personalized initial target heart rate based on hemodynamic assessment in patient with AF with rapid ventricular response. Methods: A total of 72 patients with AF were included. From the equation between preceding RR interval and left ventricular peak ejection velocity adjusted by pre-preceding RR interval, the relationship between cardiac performance representing cardiac output and heart rate was calculated, and heart rate showing maximal cardiac performance (HRmax) was obtained (Left Figure). Results: Mean HRmax was 126±21.8/min (from 75/min to 188/min). Three-fourth patients had HRmax &gt;120/minute (Right Figure). The relationship between Vpe and preceding RR interval showed two types, biphasic or monophasic resulting in similar patterns between cardiac performance and heart rate (Left Figure). HRmax &lt;100/min was found in 7 patients in whom left ventricular dilatation, dysfunction, and/or aortic regurgitation were observed (Left Figure C). Lower HRmax was independently associated with larger aorta size (r=0.48, p&lt;0.001), the absence of mitral regurgitation (r=0.43, p&lt;0.005), prescription of angiotensin converting enzyme inhibitor or angiotensin receptor blocker (r=0.39, p=0.001), and a history of heart failure (r=0.21, p=0.019). Conclusions: In most AF patients, hemodynamic approach suggested that tachycardia of 120/min or more is tolerable. The method of this study may be useful to deliver individually designed management by identifying patient that strict rate control is mandatory. In other patients, management of underlying causes for tachycardia is enough without medications for mechanical heart rate control to avoid adverse effects without clinical benefits.

Abstract 12873: Arrhythmogenic and Ischemic Cardiopathy Mimics Covid-19 Myocarditis

A 63-year-old man with a history of hypertension, hyperlipidemia and severe COVID-19 3 months earlier presented with NYHA class III-IV heart failure (HF) and intermittent claudication. Three months before, patient noted increasing dyspnea. SARS-CoV2 was verified. CT scan showed pneumonia; the severity of disease required dexamethasone and tocilizumab. Atrial fibrillation (AF) and LV EF 30% were first detected. CT scan disclosed left atrial appendage (LAA) thrombosis. Despite anticoagulants, 3 weeks later the patient developed lower limbs ischemia. Ultrasound and CT scan showed multiple thrombosis in the abdominal aorta and lower limbs arteries (Figure A). Surgery for limb ischemia was not performed due to a further decrease of LV EF to 18%. At that point, diagnosis was SARSCoV2-induced myocarditis. Нe visited our hospital for second opinion. ECG showed AF with mean heart rate (HR) of 158/min (B). Careful history collection suggested a longer AF duration which was missed and untreated due to lockdown. CRP, troponin were normal. NT-proBNP was 9326 pg/ml. After strict rate control was achieved, LV EF became 23%. Cardiac MRI with delayed gadolinium contrast revealed no fibrosis or active myocarditis (C). Angiography showed stenosis &gt;70% of the left anterior descending artery (D). After PCI, LV EF became 27%. The patient was discharged on guideline-recommended optimal medical therapy. Three months later LV EF became 30%, six months later - 47%. Thrombus in LAA was dissolved. Pulmonary vein isolation and cardioversion were performed. One week later LV EF was 60%. Currently, the patient has stable sinus rhythm and no signs of HF for &gt; 6 months. Thus, COVID-19 could contribute to the progression of atherosclerosis, modify the substrate and aggravate the severity of AF, but it was not the only cause of a serious illness in the patient. COVID-19 also had an indirect negative impact - delay the detection of cardiac pathology and cause its underdiagnosis under the guise of "post-COVID".

Bayesian Quickest Detection of Propagating Spatial Events

Rapid detection of spatial events that propagate across a sensor network is of wide interest in many modern applications. In particular, in communications, radar, IoT, environmental monitoring, and biosurveillance, we may observe propagating fields or particles. In this paper, we propose Bayesian sequential single and multiple change-point detection procedures for the rapid detection of such phenomena. Using a dynamic programming framework we derive the structure of the optimal single-event quickest detection procedure, which minimizes the average detection delay (ADD) subject to a false alarm probability upper bound. The multi-sensor system configuration is arbitrary and sensors may be mobile. In the rare event regime, the optimal procedure converges to a more practical threshold test on the posterior probability of the change point. A convenient recursive computation of this posterior probability is derived by using the propagation characteristics of the spatial event. The ADD of the posterior probability threshold test is analyzed in the asymptotic regime, and specific analysis is conducted in the setting of detecting random Gaussian signals affected by path loss. Then, we show how the proposed procedure is easy to extend for detecting multiple propagating spatial events in parallel in a multiple hypothesis testing setting. A method that provides strict false discovery rate (FDR) control is proposed. In the simulation section, it is demonstrated that exploiting the spatial properties of the event decreases the ADD compared to procedures that do not utilize this information, even under model mismatch.

AV junction ablation and cardiac resynchronization for patients with permanent atrial fibrillation and narrow QRS: the APAF-CRT mortality trial.

In patients with atrial fibrillation (AF) and heart failure (HF), strict and regular rate control with atrioventricular junction ablation and biventricular pacemaker (Ablation + CRT) has been shown to be superior to pharmacological rate control in reducing HF hospitalizations. However, whether it also improves survival is unknown. In this international, open-label, blinded outcome trial, we randomly assigned patients with severely symptomatic permanent AF >6 months, narrow QRS (≤110 ms) and at least one HF hospitalization in the previous year to Ablation + CRT or to pharmacological rate control. We hypothesized that Ablation + CRT is superior in reducing the primary endpoint of all-cause mortality. A total of 133 patients were randomized. The mean age was 73 ± 10 years, and 62 (47%) were females. The trial was stopped for efficacy at interim analysis after a median of 29 months of follow-up per patient. The primary endpoint occurred in 7 patients (11%) in the Ablation + CRT arm and in 20 patients (29%) in the Drug arm [hazard ratio (HR) 0.26, 95% confidence interval (CI) 0.10-0.65; P = 0.004]. The estimated death rates at 2 years were 5% and 21%, respectively; at 4 years, 14% and 41%. The benefit of Ablation + CRT of all-cause mortality was similar in patients with ejection fraction (EF) ≤35% and in those with >35%. The secondary endpoint combining all-cause mortality or HF hospitalization was significantly lower in the Ablation + CRT arm [18 (29%) vs. 36 (51%); HR 0.40, 95% CI 0.22-0.73; P = 0.002]. Ablation + CRT was superior to pharmacological therapy in reducing mortality in patients with permanent AF and narrow QRS who were hospitalized for HF, irrespective of their baseline EF. ClinicalTrials.gov Identifier: NCT02137187.

Wall Shear Stress Assessment of the False Lumen in Acute Type B Aortic Dissection Visualized by 4-Dimensional Flow Magnetic Resonance Imaging: An Ex-Vivo Study.

Four-dimensional flow magnetic resonance imaging (4D flow MRI) can accurately visualize and quantify flow and provide hemodynamic information such as wall shear stress (WSS). This imaging technique can be used to obtain more insight in the hemodynamic changes during cardiac cycle in the true and false lumen of uncomplicated acute Type B Aortic Dissection (TBAD). Gaining more insight of these forces in the false lumen in uncomplicated TBAD during optimal medical treatment, might result in prediction of adverse outcomes. A porcine aorta dissection model with an artificial dissection was positioned in a validated ex-vivo circulatory system with physiological pulsatile flow. 4D flow MR images with 3 set heartrates (HR; 60 bpm, 80 bpm and 100 bpm) were acquired. False lumen volume per cycle (FLV), mean and peak systolic WSS were determined from 4D flow MRI data. For validation, the experiment was repeated with a second porcine aorta dissection model. During both experiments an increase in FLV (initial experiment: ΔFLV = 2.05 ml, p < 0.001, repeated experiment: ΔFLV = 1.08 ml, p = 0.005) and peak WSS (initial experiment: ΔWSS = 1.2 Pa, p = 0.004, repeated experiment: ΔWSS = 1.79 Pa, p = 0.016) was observed when HR increased from 60 to 80 bpm. Raising the HR from 80 to 100 bpm, no significant increase in FLV (p = 0.073, p = 0.139) was seen during both experiments. The false lumen mean WSS increased significant during initial (2.71 to 3.85 Pa; p = 0.013) and non-significant during repeated experiment (3.22 to 4.00 Pa; p = 0.320). 4D flow MRI provides insight into hemodynamic dimensions including WSS. Our ex-vivo experiments showed that an increase in HR from 60 to 80 bpm resulted in a significant increase of FLV and WSS of the false lumen. We suggest that strict heart rate control is of major importance to reduce the mean and peak WSS in uncomplicated acute TBAD. Because of the limitations of an ex-vivo study, 4D flow MRI will have to be performed in clinical setting to determine whether this imaging model would be of value to predict the course of uncomplicated TBAD.

Heart rate and adverse outcomes in patients with prevalent atrial fibrillation

ObjectiveThe optimal target heart rate in patients with prevalent atrial fibrillation (AF) is not well defined. The aim of this study was to analyse the associations between heart rate and...

Lenient rate control versus strict rate control for atrial fibrillation: a protocol for the Danish Atrial Fibrillation (DanAF) randomised clinical trial

IntroductionAtrial fibrillation is the most common heart arrhythmia with a prevalence of approximately 2% in the western world. Atrial fibrillation is associated with an increased risk of death and morbidity....

A comparison of rate control and rhythm control in tachycardia induced cardiomyopathy patients with persistent atrial flutter

Abstract Background/Introduction Tachycardia induced cardiomyopathy (TIC) is a potentially reversible dysfunction of the left ventricle (LV) caused by tachyarrhythmias. Early recognition of TIC and treatment of the culprit arrhythmia using pharmacological therapy or catheter ablation results in the recovery of LV function. For atrial flutter (AFL)-induced TIC, rhythm control strategy, such as catheter ablation has been recommended. On the other hand, the efficacy of rate control strategy has remained unclear due to the difficulty of control with arrhythmic medications. However, not all patients can take rhythm control treatments due to their backgrounds. Purpose The aim of this cohort study was to establish whether rate control strategy using β-blocker is as effective as invasive rhythm control strategy for the recovery of LV function in patients with TIC due to AFL. Methods We prospectively assessed 47 symptomatic non-ischaemic heart failure (HF) patients with left ventricular ejection fraction (LVEF) below 50% and suspected TIC induced by persistent AFL. Patients were divided into rhythm control strategy group (n=22, treatment: catheter ablation, electrical cardioversion) and rate control strategy group (n=25, treatment: bisoprolol). As a sub-group study, the rate control strategy group was divided into the strict rate control group (n=12, average heart rate below 80 bpm) and lenient rate control group (n=13, average heart rate below 110 bpm). The primary outcome was the recovery of LV function, defined as an increase of LVEF over 20% or to a value of 55% or greater after 6 months. Results There were no significant differences in baseline AFL heart rate, New York Heart Association class, LVEF, estimated glomerular filtration rate, and brain natriuretic peptide between the two groups. A greater proportion of patients who showed the recovery of LVEF after 6 months belonged to the rhythm control strategy group (90.9% vs. 52.0%, p=0.004). The cumulative incidence of HF re-hospitalization was significantly higher in the rate control strategy group than in the rhythm control strategy group (hazard ratio: 4.90, 95% CI: 1.06–22.69). As a result of sub-group study, LVEF recovery was greater in the strict rate control group compared to the lenient rate control group (75.0% vs. 30.8%, p=0.027) Conclusion Rate control strategy was significantly inferior to rhythm control strategy for the recovery of LVEF in TIC patients with persistent AFL. Rhythm control should be the first choice in the management of TIC with AFL, and strict rate control should be an alternative if rhythm control is not available. Primary outcomes Funding Acknowledgement Type of funding source: None

Discharge heart rate and clinical outcomes in hospitalized heart failure patients with coexisted atrial fibrillation

Abstract Background Whether discharge heart rate for hospitalized heart failure (HF) patients with coexisted atrial fibrillation (AF) is associated with long-term clinical outcomes and whether this association differs between patients with and without beta-blockers have not been well studied. Purpose We investigated the associations between discharge heart rate and clinical outcomes in hospitalized HF patients with coexisted AF, while stratified to beta-blockers at discharge. Methods The study cohort included 1631 HF patients hospitalized primarily with AF, which was from the China PEACE Prospective Heart Failure Study. Clinical outcome was 1-year combined all-cause mortality and HF hospitalization after discharge. We analyzed association between outcome and heart rate at discharge with restricted cubic spline and Cox proportional hazard ratios (HR). Results The median age was 68 (IQR: 60- 77) years, 41.9% were women, discharge heart rate was (median (IQR)) 75 (69- 84) beats per minute (bpm), and 60.2% received beta-blockers at discharge. According to the result of restricted cubic spline plot, the relationship between discharge heart rate and clinical outcome may be nonlinear (P&amp;lt;0.01). Based on above result, these patients were divided into 3 groups: lowest &amp;lt;65 bpm, middle 65–86 bpm and highest ≥87 bpm, clinical outcomes occurred in 128 (64.32%), 624 (53.42%) and 156 (59.32%) patients in the lowest, middle, and highest groups respectively. In the Cox proportional hazard analysis, the lowest and highest groups were associated with increased risks of clinical outcome compared with the middle group (HR: 1.289, 95% confidence interval (CI): 1.056 - 1.573, p=0.013; HR: 1.276, 95% CI: 1.06 - 1.537, p=0.01, respectively). And a significant interaction between discharge heart rate and beta-blocker use was observed (P&amp;lt;0.001 for interaction). Stratified analysis showed the lowest group was associated with increased risks of clinical outcomes in patients with beta-blockers (HR: 1.584, 95% confidence interval (CI): 1.215–2.066, p=0.001). Conclusion There may be a U-curve relationship between discharge heart rate and clinical outcomes in hospitalized HF patients with coexisted AF. They may have the best clinical outcomes with heart rates of 65 - 86 bpm. And strict heart rate control (&amp;lt;65 bpm) may be avoided for patients who discharge with beta-blockers. Figure 1 Funding Acknowledgement Type of funding source: Other. Main funding source(s): This work was supported by the National Key Research and Development Program (2017YFC1310803) from the Ministry of Science and Technology of China; the CAMS Innovation Fund for Medical Science (2017-I2M-B&amp;R-02); the 111 Project from the Ministry of Education of China (B16005).

Cardiology Research Institute, Tomsk National Research Medical Center

Aim. To test the hypothesis that the combined use of ivabradine (If inhibitor) and ranolazine (late sodium channel blocker) can reduce the ventricular rate in patients with permanent atrial fibrillation (AF) resistant to standard heart rate-lowering therapy. Material and methods . The study included 25 patients with a permanent AF and an uncontrolled ventricular rate. All patients had NYHA class I-III heart failure with preserved ejection fraction. Patients took ivabradine 2,5 mg twice daily and ranolazine 250 mg twice daily. Twenty-four Holter monitoring was performed after 1, 2, 4 weeks and at the end of the study. The follow-up lasted 8 weeks. Results. In 68% and 16% of patients, strict and lenient rate control was achieved, respectively. There was no ventricular rate decrease in 12% of patients. Adverse effects developed in 4% of subjects. Conclusion. The combined use of ivabradine and ranolazine in patients with a permanent AF and uncontrolled ventricular rate reduces the rate without QT prolongation or reducing left ventricular contractile function. The findings support the hypothesis that the suppression of If current and dominant fibrillation frequency may be a new goal of permanent AF therapy. Prospective, randomized studies are needed to determine the role of drugs for ventricular rate control in patients with permanent AF and to study the effects on efficacy, safety, hospitalization frequency, and other clinical outcomes.

Including non-concurrent control patients in the analysis of platform trials: is it worth it?

BackgroundPlatform trials allow adding new experimental treatments to an on-going trial. This feature is attractive to practitioners due to improved efficiency. Nevertheless, the operating characteristics of a trial that adds arms have not been well-studied. One controversy is whether just the concurrent control data (i.e. of patients who are recruited after a new arm is added) should be used in the analysis of the newly added treatment(s), or all control data (i.e. non-concurrent and concurrent).MethodsWe investigate the benefits and drawbacks of using non-concurrent control data within a two-stage setting. We perform simulation studies to explore the impact of a linear and a step trend on the inference of the trial. We compare several analysis approaches when one includes all the control data or only concurrent control data in the analysis of the newly added treatment.ResultsWhen there is a positive trend and all the control data are used, the marginal power of rejecting the corresponding hypothesis and the type one error rate can be higher than the nominal value. A model-based approach adjusting for a stage effect is equivalent to using concurrent control data; an adjustment with a linear term may not guarantee valid inference when there is a non-linear trend.ConclusionsIf strict error rate control is required then non-concurrent control data should not be used; otherwise it may be beneficial if the trend is sufficiently small. On the other hand, the root mean squared error of the estimated treatment effect can be improved through using non-concurrent control data.

Evaluation of esmolol for heart rate control in patients with acute aortic dissection.

Acute aortic dissection is a serious and life-threatening condition that requires prompt, effective management. The purpose of this study was to evaluate the efficacy and safety of esmolol for heart rate control in patients with acute aortic dissection in the Emergency Department (ED). This was a retrospective, descriptive analysis of patients treated for type A or type B acute aortic dissection in the ED at an academic medical center. The primary outcome was the proportion of patients achieving strict (≤60bpm) or lenient (≤80bpm) heart rate control within the first 60min of therapy at the study site. The primary safety endpoint was the incidence of hypotension, defined as a systolic blood pressure of <90mmHg or a mean arterial pressure of ≤60mmHg. Of 266 patients screened, 40 patients met inclusion criteria. Thirty-three patients (82.5%) attained lenient rate control within the first 60min of esmolol therapy. Eleven patients (27.5%) achieved a strict heart rate goal within the first 60min of esmolol therapy. Five patients (12.5%) experienced an episode of hypotension during the first 3h of esmolol therapy. In patients treated with esmolol infusion for acute aortic dissection, a lenient HR goal was achieved in most patients. In contrast, esmolol was not associated with attainment of strict HR control in most patients included in this sample. Further studies are warranted to evaluate the exact role of esmolol in acute aortic dissection in a larger patient population.

Catheter Ablation of Atrial Fibrillation: Current and Evolving Indications

Catheter ablation (CA) was developed as a potentially curative procedure through electrical isolation of the pulmonary veins to isolate the main triggers of atrial fibrillation (AF). When successful, CA has clearly been shown to decrease AF recurrence and symptoms, and improve quality of life. With advancing technology, increased procedural success, and lower complication risk, CA is being used at much higher rates, with broader indications and in a diverse AF population. Symptomatic paroxysmal AF that is refractory to antiarrhythmic drugs is currently the indication for CA with the best evidence. CA for AF as first-line therapy is reserved for highly selected symptomatic patients with paroxysmal AF. Current studies have not shown an improvement in mortality or quality of life with CA as first-line therapy. In patients with persistent AF who are symptomatic despite medical therapy, CA is a reasonable therapeutic option. Although recent trials have suggested that CA reduced mortality and hospitalizations in patients with heart failure and reduced ejection fraction, the evidence is not conclusive. Therefore, current guidelines recommend CA for similar indications to patients without heart failure, but large trials comparing CA with strict rate control will be reported in the near future. Ongoing studies will assess whether CA of AF reduces major adverse cardiovascular events and whether stopping anticoagulation in the long term is possible after CA. The purpose of this review is to outline the current and evolving indications for CA of AF and the underlying evidence supporting these indications.

Strict Versus Lenient Versus Poor Rate Control Among Patients With Atrial Fibrillation and Heart Failure (from the Get With The Guidelines – Heart Failure Program)

Randomized data suggest lenient rate control (resting heart rate <110 beats/min) is noninferior to strict rate control (resting heart rate <80 beats/min) in patients with atrial fibrillation (AF). However, the optimal rate control strategy in patients with AF and heart failure (HF) remains unknown. Accordingly, we performed an observational analysis using data from the Get With The Guidelines-HF Program linked with Medicare data from July 1, 2011, to September 30, 2014. Of 13,981 patients with AF and HF, 9,100 (65.0%) had strict rate control, 4,617 (33.0%) had lenient rate control, and 264 (1.9%) had poor rate control by resting heart rate on the day of discharge. After multivariable adjustment, compared with strict rate control, lenient rate control was associated with higher adjusted risks of death (hazard ratio [HR] 1.21, 95% confidence interval [CI] 1.11 to 1.33, p <0.001), all-cause readmission (HR 1.09, 95% CI 1.03 to 1.15, p <0.002), death or all-cause readmission (HR 1.11, 95% CI 1.05 to 1.18, p <0.001), but not cardiovascular readmission (HR1.08, 95% CI 1.00 to 1.16, p = 0.051) at 90 days. Associations were comparable in patients with poor rate control and with heart rate modeled as a continuous variable. The presence or absence of reduced ejection fraction did not impact the magnitude of most observed associations. In conclusion, in patients with HF and AF, 2 of 3 patients had a heart rate that met strict-control goals at discharge. Heart rates >80 beats/min were associated with adverse outcomes irrespective of left ventricular ejection fraction.

Influence of heart rate control on exercise capacity and quality of life in patients with permanent atrial fibrillation

BackgroundThe optimal level of heart rate (HR) control in patients with atrial fibrillation (AF) is unknown. To assess the effect of rate control on cardiopulmonary exercise capacity and quality of life (QoL) in permanent AF.MethodsOne hundred forty-three patients with permanent AF were enrolled in this study. All patients received rate control medications and were followed up for 1 year. After 1-year therapy, the exercise capacity and QoL were evaluated by cardiopulmonary exercise testing (CPET) and 36-item Short-Form Health Survey, respectively. Data were compared by dividing the patients according to the following criteria: (1) whether the resting HR was ≤80 or > 80 bpm; (2) whether the exercise HR during moderate exercises on CPET was ≤110 or > 110 bpm; and (3) whether the resting HR was ≤80 bpm and exercise HR was ≤110 bpm.ResultsNo significant differences in peak oxygen uptake, peak metabolic equivalent, and anaerobic threshold were found between the strict control and lenient control groups. Both physical component summary (PCS) and mental component summary (MCS) were significantly higher for the strict rate control group than for the lenient control group. The single-factor correlation analysis revealed a negative correlation between resting HR and both PCS and MCS. The multivariable linear regression analysis indicated that both exercise HR and duration of AF linearly correlated with PCS and MCS.ConclusionsTherefore, in patients with permanent AF, exercise capacity may not be affected by the stringency of rate control, and strict rate control may be associated with better QoL.

Sex-related differences in risk factors, outcome, and quality of life in patients with permanent atrial fibrillation: results from the RACE II study.

AimsAtrial fibrillation (AF) risk factors translate into disease progression. Whether this affects women and men differently is unclear. We aimed to investigate sex differences in risk factors, outcome, and quality of life (QoL) in permanent AF patients.Methods and resultsThe Rate Control Efficacy in Permanent Atrial Fibrillation (RACE II) randomized 614 patients, 211 women and 403 men, to lenient or strict rate control. In this post hoc analysis risk factors, cardiovascular events during 3-year follow-up (cardiovascular death, heart failure hospitalization, stroke, systemic embolism, bleeding, and life-threatening arrhythmic events), outcome parameters, and QoL were compared between the sexes. Women were older (71 ± 7 vs. 66 ± 8 years, P < 0.001), had more hypertension (70 vs. 57%, P = 0.002), and heart failure with preserved ejection fraction (36 vs. 17%, P < 0.001), but less coronary artery disease (13 vs. 21%, P = 0.02). Women had more risk factors (3.7 ± 1.2 vs. 2.9 ± 1.4, P < 0.001) Cardiovascular events occurred in 46 (22%) women and 59 (15%) men (P = 0.03). Women had a 1.52 times [95% confidence interval (CI) 1.03–2.24] higher yearly cardiovascular event-rate [8.2% (6.0–10.9) vs. 5.4% (4.1–6.9), P = 0.03], but this was no longer significant after adjusting for the number of underlying risk factors. Women had reduced QoL, irrespective of age and heart rate but negatively influenced by their risk factors.ConclusionIn this permanent AF population, women had more accumulation of AF risk factors than men. The observed higher cardiovascular event rate in women was no longer significant after adjusting for the number of risk factors. Further, QoL was negatively influenced by the higher number of risk factors in women. This suggests that sex differences may be driven by the greater risk factor burden in women.

Heightened risk of intensive rate control in patients with atrial fibrillation who are obese or have type 2 diabetes: A critical review and re-evaluation.

Atrial fibrillation (AF) is common in patients with obesity and diabetes; the arrhythmia (if long-standing) is typically managed by rate control and anticoagulation. However, the coexistence of these two metabolic disorders complicates therapeutic options for rate control. The likely pathogenesis of AF in these patients is an expansion of epicardial adipose tissue whose inflammation is transmitted to the left atrium causing electromechanical remodeling. However, this same process is also transmitted to the left ventricle (LV), impairing its distensibility and its ability to tolerate volume, leading to heart failure with preserved ejection fraction. Unfortunately, the latter diagnosis (although commonly present in patients with AF and a coexistent metabolic disorder) is often ignored. To achieve rate control, physicians prescribe intensive treatment with atrioventricular (AV) nodal-blocking drugs, often at doses that are titrated to blunt exercise as well as resting heart rate responses. However, strict rate control (target rate, <80/min) is associated with somewhat worse outcomes than lenient rate control (target rate, <110/min). Furthermore, any rate slowing that facilitates diastolic filling may aggravate filling pressures that are already disproportionately increased because the LV is stiff and overfilled as a result of cardiac inflammation. Rate slowing in AF with beta blockers may not achieve the benefit expected from the blockade of adrenergically mediated cardiotoxicity, and some AV nodal-blocking drugs (digoxin and dronedarone) can increase the risk of death in patients with AF. Finally, cardiac fibrosis in obesity and diabetes may affect the conduction system, which can predispose to serious bradyarrhythmias if patients are prescribed AV nodal-blocking drugs.