Low resting heart rates are associated with new-onset atrial fibrillation in patients with vascular disease: results of the ONTARGET/TRANSCEND studies

Heart rate-lowering drugs and outcomes in hypertension and/or cardiovascular disease: a meta-analysis

BACKGROUND AND AIMS

The benefits of heart rate (HR)-lowering drug treatment in hypertension remain controversial. The effects of HR lowering on cardiovascular (CV) outcomes, mortality, and adverse events in patients with hypertension and/or CV disease were evaluated.

METHODS

PubMed, the Embase, and the Cochrane Library were searched for randomized trials comparing HR-lowering drugs with placebo or less intensive treatment. Risk ratios and 95% confidence intervals for eight outcomes were calculated (random-effects model). Subgroup analyses for a standard HR reduction were used to compare risk estimates in different HR groups or age strata (PROSPERO CRD42024540924).

RESULTS

The database included 74 HR-lowering treatment trials (n = 157 764 patients). The average HR reduction over 2.7 years was 8.2 b.p.m. (baseline/attained HR: 76.2/65.6 b.p.m.). HR-lowering reduced coronary heart disease by 16%, heart failure by 9%, CV mortality by 14%, and all-cause mortality by 13% but increased adverse event-driven discontinuations by 25%. Significant mortality reductions were noted in post-acute myocardial infarction and heart failure. No significant outcome changes were observed with HR reduction in hypertension without CV disease, while the entire hypertensive population experienced increased stroke and mortality. Threshold analysis revealed that the effect on outcomes was not different across cutoffs (from ≥80 b.p.m. to almost 70 b.p.m.), except for heart failure. Treatment outcome effects were not different across progressively lower targets (from ≥70 b.p.m. to <65 b.p.m.), except for permanent discontinuations, which showed an incremental trend.

CONCLUSIONS

The HR reduction benefits are context-dependent. Optimising outcomes while considering potential risks, targeting 65-70 b.p.m. for all HR thresholds above 70 b.p.m. seems reasonable.

Heart Rate at Rest and Incident Atrial Fibrillation in Patients With Diastolic Dysfunction

Diastolic dysfunction (DD) is associated with incident atrial fibrillation (AF). The influence of heart rate at rest (RHR) on incident AF in patients with DD has not been investigated. The goal of this study is to assess the influence of RHR on incident AF in patients with DD. Patients from a large health system with no previous history of AF, a left ventricular ejection fraction ≥50%, and documented DD on echocardiography were divided into quartiles (<66, 66 to 76, 77 to 91, >91 beats per minute) based on RHR. Incident AF was estimated using AF hospitalization during follow-up. Hazard ratios (HR) for AF hospitalization and all-cause death were calculated with a Cox proportional hazards model. A total of 19,046 patients were analyzed. Over a median follow-up of 42.2 months, 742 (3.9%) patients were hospitalized for AF. Both slower and faster RHR were associated with increased risk of AF hospitalization (HR 1.40, confidence interval [CI] 1.14 to 1.71, p = 0.001, HR 1.23, CI 0.99 to 1.53, p = 0.06 and HR 1.72, CI 1.38 to 2.14, p <0.001, for quartiles 1, 2, and 4, respectively), suggesting a J-shaped relation. Progressive increase in all-cause death was noted with faster RHR (HR1.19 per quartile increase, CI 1.16 to 1.22, p <0.001). These results persisted after adjustment for age, cardiovascular co-morbidities, grade of DD, and β-blocker use. In conclusion, this large, real-world analysis indicates increased risk of incident AF with slower and faster RHR in patients with DD. Randomized trials are needed to evaluate the potential of RHR modification to mitigate the risk of incident AF.

Lower heart rates and beta-blockers are associated with new-onset atrial fibrillation

Background

Lower heart rates (HRs) prolong diastole, which increases filling pressures and wall stress. As a result, lower HRs may be associated with higher brain natriuretic peptide (BNP) levels and incident atrial fibrillation (AF). Beta-blockers may increase the risk for AF due to suppression of resting HRs.

Objective

Examine the relationships of HR, BNP, beta-blockers and new-onset AF in the REVEAL-AF and SPRINT cohort of subjects at risk for developing AF.

Methods

In REVEAL-AF, 383 subjects without a history of AF and a mean CHA₂DS₂VASC score of 4.4 ± 1.3 received an insertable cardiac monitor and were followed up to 30 months. In SPRINT, 7595 patients without prior history of AF and a mean CHA₂DS₂VASC score of 2.3 ± 1.2 were followed up to 60 months.

Results

The median daytime HR in the REVEAL-AF cohort was 75bpm [IQR 68-83]. Subjects with below-median HRs had 2.4-fold higher BNP levels compared to subjects with above-median HRs (median BNP [IQR]: 62 pg/dl [37-112] vs. 26 pg/dl [13-53], p < 0.001). HRs <75bpm were associated with a higher incidence of AF: 37% vs. 27%, p < 0.05. This was validated in the SPRINT cohort after adjusting for AF risk factors. Both a HR < 75bpm and beta-blocker use were associated with a higher rate of AF: 1.9 vs 0.7% (p < 0.001) and 2.5% vs. 0.6% (p < 0.001), respectively. The hazard ratio for patients on beta-blockers to develop AF was 3.72 [CI 2.32, 5.96], p < 0.001.

Conclusions

Lower HRs are associated with higher BNP levels and incident AF, mimicking the hemodynamic effects of diastolic dysfunction. Suppression of resting HR by beta-blockers could explain their association with incident AF.

Resting heart rate and risk of atrial fibrillation in Chinese general population: Kailuan prospective cohort study

OBJECTIVE

Previous research has shown an association of higher heart rate with an increased risk of atrial fibrillation (AF). However, the relationship between resting heart rate (RHR) and AF is unknown. The aim of this study was to investigate the association between RHR and AF in the general population of China.

DESIGN

Prospective observational cohort study.

SETTING

Community based.

PARTICIPANTS

A total of 46 126 individuals from the Kailuan study who participated in the first three surveys (2006/2007, 2008/2009 and 2010/2011) and were followed up at 2-year intervals were enrolled.

PRIMARY OUTCOME MEASURES

The association between RHR and risk of incident AF was evaluated using Cox proportional hazards regression and restricted cubic spline models.

RESULTS

Two hundred and forty-one individuals (0.52%) developed AF during 7.5 years of follow-up. After adjustment for age, sex, low-density and high-density lipoprotein, physical activity, alcohol consumption, smoking status, body mass index, mean systolic blood pressure, and history of diabetes and hypertension, the HRs were 2.32 (95% CI 1.45 to 3.72) for an RHR <60 beats/min and 2.80 (1.13 to 6.94) for an RHR ≥100 beats/min in comparison with an RHR of 70-80 beats/min. Restricted cubic spline models revealed a U-shaped relationship between RHR and incident AF.

CONCLUSION

These findings indicate that RHR and incident AF have a U-shaped relationship in the Chinese general population. Both lower and higher RHRs were associated with an increased risk of AF.

Initial In-Hospital Visit-to-Visit Heart Rate Variability Is Associated with Higher Risk of Atrial Fibrillation in Patients with Acute Ischemic Stroke

BACKGROUND

To evaluate the association between the visit-to-visit heart rate variability and the risk of atrial fibrillation (AF) in acute ischemic stroke (AIS).

METHODS

We analyzed the data of 8179 patients with AIS. Patients without AF on 12-lead electrocardiography underwent further 24 h Holter monitoring. They were categorized into four subgroups according to the visit-to-visit heart rate variability expressed as the coefficient of variation in heart rate (HR-CV). Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using the HR-CV < 0.08 subgroup as a reference.

RESULTS

The adjusted OR of paroxysmal AF was 1.866 (95% CI = 1.205-2.889) for the HR-CV ≥ 0.08 and <0.10 subgroup, 1.889 (95% CI = 1.174-3.038) for the HR-CV ≥ 0.10 and <0.12 subgroup, and 5.564 (95% CI = 3.847-8.047) for the HR-CV ≥ 0.12 subgroup. The adjusted OR of persistent AF was 2.425 (95% CI = 1.921-3.062) for the HR-CV ≥ 0.08 and <0.10 subgroup, 4.312 (95% CI = 3.415-5.446) for the HR-CV ≥ 0.10 and <0.12 subgroup, and 5.651 (95% CI = 4.586-6.964) for the HR-CV ≥ 0.12 subgroup.

CONCLUSIONS

HR-CV can facilitate the identification of patients with AIS at a high risk of paroxysmal AF.

Frequency of Visit-to-Visit Variability of Resting Heart Rate and the Risk of New-Onset Atrial Fibrillation in the General Population

Resting heart rate (RHR) has been an established predictor for atrial fibrillation (AF). However, the association of visit-to-visit heart rate variability (VVHRV) with new-onset AF risk over long term remains unclear. Our study investigates the relation of VVHRV to new-onset AF in general population in the prospective study of the Kailuan cohort. A total of 46,126 individuals without arrhythmia were included. They underwent 3 health examinations from 2006 to 2010 and performed follow up. VVHRV was measured by coefficient of variation (CV), variability independent of the mean (VIM), and standard deviation (SD). Participants were separately divided into 5 categories by quintiles of visit-to-visit RHR-CV, RHR-VIM and RHR-SD. Multivariate Cox regression and restricted cubic spline models were performed to establish the association between VVHRV and new-onset AF. 241 new-onset AF occurred during a median follow-up of 7.54 years. The incidence of new-onset AF in the group of the lowest (Q1) and highest quintiles (Q5) of RHR-CV were higher than that in other groups. The HRs for the new-onset AF were 2.07 (95% CI, 1.34-3.21, p < 0.01), in the highest quintile group(Q5) compared with group Q2, and 1.89(95% CI, 1.20-2.97, p < 0.01) in the lowest quintile group(Q1) compared with group Q2. The risk for new-onset AF showed a similar trend using RHR-VIM (p < 0.01) and RHR-SD (p < 0.05) parameters. Further sensitivity analyses indicated the consistent results in subjects without prior cardiovascular disease and without taking beta blockers or CCB. To match the covariates, analyses were also performed by propensity score matching, and prominent trends were also found in RHR-SD and RHR-VIM. In conclusion, the study indicated that higher and lower VVHRV were associated with the increasing risk of new-onset AF, which supporting a U-shaped curve existence.

Heart Rate, Brain Imaging Biomarkers and Cognitive Impairment in Older (≥63 years) Women

Evidence on the relations between heart rate, brain morphology, and cognition is limited. We examined the associations of resting heart rate (RHR), visit-to-visit heart rate variation (VVHRV), brain volumes and cognitive impairment. The study sample consisted of postmenopausal women enrolled in the Women's Health Initiative Memory Study and its ancillary MRI sub-studies (WHIMS-MRI 1 and WHIMS-MRI 2) without a history of cardiovascular disease, including 493 with one and 299 women with 2 brain magnetic resonance imaging (MRI) scans. HR readings were acquired annually starting from baseline visit (1996-1998). RHR was calculated as the mean and VVHRV as standard deviation of all available HR readings. Brain MRI scans were performed between 2005 and 2006 (WHIMS-MRI 1), and approximately 5 years later (WHIMS-MRI 2). Cognitive impairment was defined as incident mild cognitive impairment or probable dementia until December 30, 2017. An elevated RHR was associated with greater brain lesion volumes at the first MRI exam (7.86 cm3 [6.48, 9.24] vs 4.78 cm3 [3.39, 6.17], p-value <0.0001) and with significant increases in lesion volumes between brain MRI exams (6.20 cm3 [4.81, 7.59] vs 4.28 cm3 [2.84, 5.73], p-value = 0.0168). Larger ischemic lesion volumes were associated with a higher risk for cognitive impairment (Hazard Ratio [95% confidence interval], 2.02 [1.18, 3.47], p-value = 0.0109). Neither RHR nor VVHRV were related to cognitive impairment. In sensitivity analyses, we additionally included women with a history of cardiovascular disease to the study sample. The main results were consistent to those without a history of cardiovascular disease. In conclusion, these findings show an association between elevated RHR and ischemic brain lesions, probably due to underlying subclinical disease processes.

Independent effect of physical activity and resting heart rate on the incidence of atrial fibrillation in the general population

While physical activity (PA) may influence resting heart rate (RHR), and a low RHR may be a risk factor for atrial fibrillation (AF), controversy exists regarding the association between PA and development of AF. Using data from a Korean, prospective population cohort, we investigated the independent effect of PA and RHR on the incidence of AF in the general population. A total of 8,811 participants aged 40-69 years were analyzed. Total PA assessed based on questionnaires was divided into quartiles, with the lowest to the highest being Q1, Q2, Q3, and Q4. During a median follow-up of 139 months, AF developed in 167 participants (1.9%). Q3 of total PA was associated with a significantly lower risk of AF than Q1 even after adjusting for RHR as a covariate, but Q4 was not. The risk of AF was higher in participants with RHR < 60 bpm than in those with RHR 70-85 bpm, and the significance persisted after adjusting for PA as a covariate. This study showed that a moderate amount of total PA was associated with a lower risk of incident AF independent of RHR and that low RHR was an independent risk factor for AF in the general Korean population.

Resting Heart Rate and the Risk of Atrial Fibrillation

In a previous meta-analysis, it was demonstrated that the resting heart rate (RHR) is a potential risk factor for atrial fibrillation (AF). However, the results of that meta-analysis were conflicting, and the relationship between the RHR and AF is still not well established. In the current meta-analysis, our aim is to update evidence with a better statistical model. We searched the Cochrane Library, PubMed, and Embase databases for relevant studies and used a "one-stage approach" with a restricted cubic spline model to summarize the dose-specific relationships between the RHR and AF. Relative risk (RR) was used to measure the effects. In total, 10 studies were included, with a total of 18,630 cases of AF among 431,432 participants. In the dose-response analysis, there was evidence of a nonlinear association between the RHR and the risk of AF (nonlinearity, P < 0.0001), which exhibited a significant J-shaped association between the two factors. An RHR between 68 and 80 bpm had the lowest risk of AF. Among people who had RHR < 70 bpm, the summary RR was 1.09 per 10-RHR decrease (95% confidence interval [CI] = 1.06-1.12; P < 0.001). The results were similar for participants with RHR > 70 bpm (per 10 bpm increase) (RR = 1.06, 95% CI = 1.03-1.08; P < 0.001). Our dose-response meta-analysis revealed a significant J-shaped association between the RHR and AF. Both low RHR and high RHR were associated with an increased risk of AF compared with a modest RHR of 68-80 bpm.

Resting Heart Rate and Ischemic Stroke in Patients with Heart Failure

BACKGROUND

Although high resting heart rate (RHR) is known to be associated with an increased risk of mortality and hospital admission in patients with heart failure, the relationship between RHR and ischemic stroke remains unclear. This study is aimed at investigating the relationship between RHR and ischemic stroke in patients with heart failure in sinus rhythm.

METHODS

We examined 2,060 patients with systolic heart failure in sinus rhythm from the Warfarin versus Aspirin in Reduced Cardiac Ejection Fraction trial. RHR was determined from baseline electrocardiogram, and was examined as both a continuous variable and a categorical variable using quartiles. Ischemic strokes were identified during follow-up and adjudicated by physician review.

RESULTS

During 3.5 ± 1.8 years of follow-up, 77 patients (5.3% from Kaplan-Meier [KM] curve) experienced an ischemic stroke. The highest incidence of ischemic stroke (21/503 [KM 6.9%]) was observed in the lowest RHR quartile (RHR <64 beats/min) compared to other groups; 22/573 (KM 5.3%) in 64-70 beats/min, 13/465 (KM 3.5%) in 71-79 beats/min, and 21/519 (KM 5.4%) in RHR >79 beats/min (p = 0.693). Multivariable Cox proportional hazards analysis revealed that RHR was significantly associated with ischemic stroke (hazard ratio per unit decrease: 1.07, 95% CI 1.02-1.13, when RHR <64/beats/min; p = 0.038), along with a history of stroke or transient ischemic attack and left ventricular ejection fraction.

CONCLUSIONS

In contrast to its beneficial effect on mortality and hospital re-admissions, lower RHR may increase the risk of ischemic stroke in patients with systolic heart failure in sinus rhythm.

Relation of Resting Heart Rate to Incident Atrial Fibrillation (from the Henry Ford Hospital Exercise Testing Project)

Autonomic nervous system (ANS) dysfunction plays a role in atrial fibrillation (AF) initiation. Cardiorespiratory fitness modulates ANS function and is inversely associated with resting heart rate (RHR) and risk of AF. Thus, we sought to study the association between RHR, as a surrogate for ANS function, and incident AF independent of exercise capacity (EC). We analyzed 51,436 subjects without previous AF who underwent a clinically indicated exercise stress test. Incident AF was ascertained through claims files. RHR was measured before stress testing, and EC was estimated by peak metabolic equivalents of task. We studied the association between RHR categories (<70, 70 to 85 [reference], and >85 beats/min) and incident AF using Cox models adjusted for risk factors and for EC. We tested for interaction between RHR and age, gender, smoking, and EC. Mean (SD) age was 53 (13) years, 53% were men, and 28% were black. Participants with RHR <70 beats/min were older, more likely to be men, have higher EC, and more likely to smoke but less likely to have diabetes and hypertension. Over a median of 5.5 years, RHR <70 beats/min was associated with 14% increased risk of AF (95 CI 6% to 25%) in fully adjusted models, whereas RHR >85 beats/min was not associated with AF risk after adjusting for EC. Results for RHR analyzed continuously and by quartile were similar. No interaction was seen. In conclusion, subjects with low RHR at all levels of EC are at increased risk of AF and may benefit from heart rhythm surveillance, particularly in the presence of other AF risk factors.

Association Between Heart Rate at Rest and Incident Atrial Fibrillation (from the Copenhagen Electrocardiographic Study)

Heart rate (HR) at rest is a well-known marker of cardiovascular morbidity and mortality. Results on the association between HR and incident atrial fibrillation (AF) have, however, been conflicting. Using digital electrocardiograms from 281,451 primary care patients, we aimed to describe the association between HR at rest and the hazards of incident AF. Secondary end points were death from all causes and pacemaker implantation. Data on drug use, co-morbidity, and outcomes were collected from nationwide administrative health care registries. During a median follow-up time of 8.4 years, 15,666 subjects were observed to develop AF, of which 1,631 were lone AF. A HR at rest from 30 to 51 beats/min was associated with an adjusted hazard ratio of 1.16 (95% CI 1.06 to 1.27) for AF compared with the reference group (66 to 72 beats/min). From 72 beats/min and upward, the hazard ratio of AF increased in a dose-response manner, reaching an adjusted hazard ratio of 1.36 (95% CI 1.26 to 1.46) for HR between 95 and 120 beats/min. Both for low and high HR, the associations were accentuated for the outcome lone AF (adjusted hazard ratios of 1.48, 95% CI 1.19 to 1.84 and 1.84, 95% CI 1.47 to 2.30 for HR between 30 to 51 and 95 to 120 beats/min, respectively). For death from all causes, the hazard increased almost linearly with increasing HR. A HR at rest from 30 to 51 beats/min was associated with an adjusted hazard ratio of 1.80 (95% CI 1.46 to 2.21) for pacemaker implantation. In conclusion, a U-shaped association was found between HR at rest and incident AF, and this association was strongest for the outcome lone AF.

Heart rate and ischemic stroke: the REasons for Geographic And Racial Differences in Stroke (REGARDS) study

BACKGROUND

The association between resting heart rate and ischemic stroke remains unclear.

AIM

To examine the association between resting heart rate and ischemic stroke.

METHODS

A total of 24 730 participants (mean age: 64 ± 9·3 years; 59% women; 41% blacks) from the REasons for Geographic And Racial Differences in Stroke (REGARDS) study who were free of stroke at the time of enrollment (2003-2007) were included in this analysis. Resting heart rate was determined from baseline electrocardiogram data. Heart rate was examined as a continuous variable per 10 bpm increase and also as a categorical variable using tertiles ( <61 bpm, 61 to 70 bpm, and >70 bpm). First-time ischemic stroke events were identified during follow-up and adjudicated by physician review.

RESULTS

Over a median follow-up of 7·6 years, a total of 646 ischemic strokes occurred. In a Cox regression model adjusted for socio-demographics, cardiovascular risk factors, and potential confounders, each 10 bpm increase in heart rate was associated with a 10% increase in the risk of ischemic stroke (hazard ratio = 1·10, 95% confidence interval = 1·02, 1·18). In the categorical model, an increased risk of ischemic stroke was observed for heart rates in the middle (hazard ratio = 1·29, 95% confidence interval = 1·06, 1·57) and upper (hazard ratio = 1·37, 95% confidence interval = 1·12, 1·67) tertiles compared with the lower tertile. The results were consistent when the analysis was stratified by age, gender, race, exercise habits, hypertension, and coronary heart disease.

CONCLUSION

In REGARDS, high resting heart rates were associated with an increased risk of ischemic stroke compared with low heart rates. Further research is needed to examine whether interventions aimed to reduce heart rate decrease stroke risk.