Elevated heart rate and atherosclerosis: An overview of the pathogenetic mechanisms

Nocturnal pulse rate correlated with ambulatory blood pressure and target organ damage in patients with chronic kidney disease

The relationship between resting pulse rate (PR) and the occurrence of hypertension and cardiovascular (CV) mortality has been described in the general population. Few studies have examined the relationship between ambulatory PR, ambulatory blood pressure (BP), and target organ damage (TOD) in patients with chronic kidney disease (CKD). A total of 1509 patients with CKD were recruited in our hospital. Ambulatory blood pressure monitoring (ABPM) over a 24-hours period was performed and referenced with clinical data in this cross-sectional study. TOD was measured by estimated glomerular filtration rate (eGFR), left ventricular hypertrophy (LVH), and carotid intima-media thickness (cIMT). Univariate and multivariate analyses were used to evaluate the relationship between PR, BP, and TOD. The percentage of male patients was 58.3% with a mean age of 44.6 ± 16.2 years. Nocturnal PR rather than 24-hours PR or daytime PR was an independent risk factor for clinical hypertension, 24-hours hypertension, BP dipper state, poor renal function, and LVH. In addition, the authors found that nighttime PR >74 beats/min (bpm) group was independently associated with clinical hypertension, 24-hours hypertension, day and night hypertension, nondipping BP, lower eGFR, and LVH when compared with nighttime PR <64 bpm group. Furthermore, 1:1 propensity score matching between PR ≤74 bpm group and PR >74 bpm group was performed. Multivariate analyses indicated nighttime PR >74 bpm remained independently associated with clinical hypertension, daytime and nighttime hypertension, and LVH. An increased nocturnal PR is associated with TOD, higher BP, and nondipping BP in patients with CKD.

Ivabradine for the Treatment of Cardiovascular Diseases

Higher heart rate (HR) is independently related to worse outcomes in various cardiac diseases, including hypertension, coronary artery disease, and heart failure (HF). HR is determined by the pacemaker activity of cells within the sinoatrial node. The hyperpolarization-activated cyclic nucleotide-gated (HCN) 4 channel, one of 4 HCN isoforms, generates the I_f current and plays an important role in the regulation of pacemaker activity in the sinoatrial node. Ivabradine is a novel and only available HCN inhibitor, which can reduce HR and has been approved for stable angina and chronic HF in many countries other than Japan. In this review, we summarize the current knowledge of the HCN4 channel and ivabradine, including the function of HCN4 in cardiac pacemaking, the mechanism of action of I_f inhibition by ivabradine, and the pharmacological and clinical effects of ivabradine in cardiac diseases as HF, coronary artery disease, and atrial fibrillation.

Role of High-Dose Beta-Blockers in Patients with Heart Failure with Preserved Ejection Fraction and Elevated Heart Rate

BACKGROUND

Beta-blockers in high target doses are recommended for heart failure with reduced ejection fraction (HFrEF) but not for preserved ejection fraction (HFpEF). Treatment benefits are often more pronounced in high-risk subgroups, and patients with HFpEF with heart rate ≥70 beats per minute have emerged as such a high-risk subgroup. We examined the associations of high-dose beta-blocker use with outcomes in these patients.

METHODS

Of the 8462 hospitalized patients with heart failure with ejection fraction ≥50% in the Medicare-linked Organized Program to Initiate Lifesaving Treatment in Hospitalized Patients with Heart Failure (OPTIMIZE-HF) registry, 5422 had a discharge heart rate ≥70 beats per minute. Of these, 4537 had no contraindications to beta-blocker use, of which 2797 (2592 with dose data) received prescriptions for beta-blockers. Of the 2592, 730 received high-dose beta-blockers, defined as atenolol ≥100 mg/day, carvedilol ≥50 mg/day, metoprolol tartrate or succinate ≥200 mg/day, or bisoprolol ≥10 mg/day, and 1740 received no beta-blockers. Using propensity scores for the receipt of high-dose beta-blockers, we assembled a matched cohort of 1280 patients, balanced on 58 characteristics.

RESULTS

All-cause mortality occurred in 63% and 68% of matched patients receiving high-dose beta-blocker vs no beta-blocker, respectively, during 6 years (median, 2.8) of follow-up (hazard ratio, 0.86; 95% confidence interval, 0.75-0.98; P = .027). The hazard ratios (95% confidence intervals) for all-cause readmission and the combined endpoint of all-cause readmission or all-cause mortality associated with high-dose beta-blocker use were 0.90 (0.81-1.02) and 0.89 (0.80-1.00), respectively.

CONCLUSIONS

In patients with HFpEF and heart rate ≥70 beats per minute, high-dose beta-blocker use was associated with a significantly lower risk of death. Future randomized controlled trials are needed to examine this association.

Dyslipidaemia in type 2 diabetes mellitus: bad for the heart

PURPOSE OF REVIEW

Type 2 diabetes mellitus (T2DM) is associated with increased coronary heart disease (CHD) morbidity and mortality. These patients are also more prone to heart failure, arrhythmias and sudden cardiac death. Furthermore, coronary interventions performed in such high-risk patients have worse outcomes. In this narrative review, we discuss the role of diabetic dyslipidaemia on the risk of CHD in patients with T2DM. The effects of hypolipidaemic, antihypertensive and antidiabetic drugs on lipid and glucose metabolism in T2DM are also considered.

RECENT FINDINGS

Among CHD risk factors, diabetic dyslipidaemia characterized by moderately elevated low-density lipoprotein (LDL) cholesterol, increased triglycerides and small, dense LDL particles as well as decreased high-density lipoprotein cholesterol levels may contribute to the increased CHD risk associated with T2DM. Hypolipidaemic, antihypertensive and antidiabetic drugs can affect lipid and glucose parameters thus potentially influencing CHD risk. Such drugs may improve not only the quantity, but also the quality of LDL as well as postprandial lipaemia.

SUMMARY

Current data highlight the importance of treating diabetic dyslipidaemia in order to minimize CHD risk. Both fasting and postprandial lipids are influenced by drugs in patients with T2DM; physicians should take this into consideration in clinical decision making.

Effects of resting heart rate on blood pressure and hypertension in Chinese children: findings from blood pressure surveillance program

The purpose of this study was to analyze the association between resting heart rate (RHR) and prevalence of hypertension in Chinese children and to identify if this association was mediated by body mass index (BMI). The data of 5445 children who participated in the Blood Pressure Surveillance Program (2011-2017) were analyzed in this study. Children were divided into four groups according to quartiles of RHR in boys and girls, respectively. Compared to those in the first quartile, boys and girls in the fourth quartile were 3.06 (95% CI 2.12, 4.41) and 4.94 (95% CI 3.21, 7.61) times more likely to have hypertension, respectively. Meanwhile, every 10 beats per minute (bpm) increase in RHR was associated with a 41% (95% CI 1.27, 1.56) and 66% (95% CI 1.49, 1.85) greater risk of hypertension in boys and girls, respectively. There were no significant interactions between RHR and BMI on the prevalence of hypertension. This study confirms the existence of a relationship between elevated RHR and increased risk of hypertension in children, independent of BMI. An elevated RHR could be considered as a risk factor for the risk assessment of hypertension, no matter from a clinical setting or a public health perspective.

Role of ivabradine in management of stable angina in patients with different clinical profiles

In chronic stable angina, elevated heart rate contributes to the development of symptoms and signs of myocardial ischaemia by increasing myocardial oxygen demand and reducing diastolic perfusion time. Accordingly, heart rate reduction is a well-known strategy for improving both symptoms of myocardial ischaemia and quality of life (QOL). The heart rate-reducing agent ivabradine, a direct and selective inhibitor of the I_f current, decreases myocardial oxygen consumption while increasing diastolic time, without affecting myocardial contractility or coronary vasomotor tone. Ivabradine is indicated for treatment of stable angina and chronic heart failure (HF). This review examines available evidence regarding the efficacy and safety of ivabradine in stable angina, when used as monotherapy or in combination with beta-blockers, in particular angina subgroups and in patients with stable angina with left ventricular systolic dysfunction (LVSD) or HF. Trials involving more than 45 000 patients receiving treatment with ivabradine have shown that this agent has antianginal and anti-ischaemic effects, regardless of age, sex, severity of angina, revascularisation status or comorbidities. This heart rate-lowering agent might also improve prognosis, reduce hospitalisation rates and improve QOL in angina patients with chronic HF and LVSD.

Heart Rate and Blood Pressure: "Connecting the Dots" in Epidemiology and Pathophysiology

There is robust evidence from epidemiological and clinical studies showing that elevated heart rate (HR) constitutes a powerful predictor of morbidity and mortality in patients with hypertension, underlining the significance of HR measurement in them. Autonomous nervous system dysfunction and atherosclerosis are important features in the pathogenesis of the untoward events. However, the relationship between HR and blood pressure (BP) is complex and differs depending on the type of BP measurement which is considered. This differentiation implicates complex physiological mechanisms and is of clinical importance regarding the divergent effect of the different types of antihypertensive agents on these parameters. The aim of this review is to summarize the current evidence on the relationship between HR and BP based on epidemiological, clinical, and experimental studies.

A multiscale approach for determining the morphology of endothelial cells at a coronary artery

The morphology of endothelial cells (ECs) may be an indication for determining atheroprone sites. Until now, there has been no clinical imaging technique to visualize the morphology of ECs in the arteries. The present study introduces a computational technique for determining the morphology of ECs. This technique is a multiscale simulation consisting of the artery scale and the cell scale. The artery scale is a fluid-structure interaction simulation. The input for the artery scale is the geometry of the coronary artery, that is, the dynamic curvature of the artery due to the cardiac motion, blood flow, blood pressure, heart rate, and the mechanical properties of the blood and the arterial wall, the measurements of which can be obtained for a specific patient. The results of the artery scale are wall shear stress (WSS) and cyclic strains as the mechanical stimuli of ECs. The cell scale is an inventive mass-and-spring model that is able to determine the morphological response of ECs to any combination of mechanical stimuli. The results of the multiscale simulation show the morphology of ECs at different locations of the coronary artery. The results indicate that the atheroprone sites have at least 1 of 3 factors: low time-averaged WSS, high angle of WSS, and high longitudinal strain. The most probable sites for atherosclerosis are located at the bifurcation region and lie on the myocardial side of the artery. The results also indicated that a higher dynamic curvature is a negative factor and a higher pulse pressure is a positive factor for protection against atherosclerosis.

Heart Rate and Outcomes in Hospitalized Patients With Heart Failure With Preserved Ejection Fraction

BACKGROUND

A lower heart rate is associated with better outcomes in patients with heart failure (HF) with reduced ejection fraction (EF). Less is known about this association in patients with HF with preserved ejection fraction (HFpEF).

OBJECTIVES

The aims of this study were to examine associations of discharge heart rate with outcomes in hospitalized patients with HFpEF.

METHODS

Of the 8,873 hospitalized patients with HFpEF (EF ≥50%) in the Medicare-linked OPTIMIZE-HF (Organized Program to Initiate Lifesaving Treatment in Hospitalized Patients with Heart Failure) registry, 6,286 had a stable heart rate, defined as ≤20 beats/min variation between admission and discharge. Of these, 2,369 (38%) had a discharge heart rate of <70 beats/min. Propensity scores for discharge heart rate <70 beats/min, estimated for each of the 6,286 patients, were used to assemble a cohort of 2,031 pairs of patients with heart rate <70 versus ≥70 beats/min, balanced on 58 baseline characteristics.

RESULTS

The 4,062 matched patients had a mean age of 79 ± 10 years, 66% were women, and 10% were African American. During 6 years (median 2.8 years) of follow-up, all-cause mortality was 65% versus 70% for matched patients with a discharge heart rate <70 versus ≥70 beats/min, respectively (hazard ratio [HR]: 0.86; 95% confidence interval [CI]: 0.80 to 0.93; p < 0.001). A heart rate <70 beats/min was also associated with a lower risk for the combined endpoint of HF readmission or all-cause mortality (HR: 0.90; 95% CI: 0.84 to 0.96; p = 0.002), but not with HF readmission (HR: 0.93; 95% CI: 0.85 to 1.01) or all-cause readmission (HR: 1.01; 95% CI: 0.95 to 1.08). Similar associations were observed regardless of heart rhythm or receipt of beta-blockers.

CONCLUSIONS

Among hospitalized patients with HFpEF, a lower discharge heart rate was independently associated with a lower risk of all-cause mortality, but not readmission.

Association of elevated resting pulse rate with increased risk of hypertension development in children: A prospective study in Suzhou, China

BACKGROUND

Elevated resting heart rate (RHR) or resting pulse rate (RPR) is associated with increased risk of hypertension development. However, information is limited to adults. The purpose of this study is to analyze this association among Chinese children in a prospective design.

METHODS

A total of 4861 children who participated in the Blood Pressure Surveillance Program (2011-2017) were selected in this research. To investigate the association between RPR and hypertension development, children were divided into 4 groups according to the quartiles of RPR at baseline. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using logistic regression model.

RESULTS

Over a mean follow-up of 3.0 ± 0.1 years, there were 384 cases of incident hypertension. Compared to boys and girls in the 1st quartile, those in the 4th quartile were 1.73 (95% CI 1.13, 2.65), 2.22 (95% CI 1.43, 3.45) times more likely to have hypertension, respectively. Every 10 bpm increase in RPR was associated with a 26% greater risk of hypertension development in boys (OR: 1.26; 95% CI 1.10, 1.44), while this risk was 1.28 (95% CI 1.13, 1.44) in girls. Baseline blood pressure (BP) and body mass index (BMI) did not have significant interactions with RPR on risk of hypertension development.

CONCLUSION

This study confirms the relationship between elevated RPR and increased risk of hypertension development in children, independent of confounders including baseline BP and BMI. An elevated RPR could be considered as a risk factor for the assessment of hypertension, no matter from a clinical setting or a public health perspective.

Associations of resting heart rate with endothelium-dependent vasodilation and shear rate

Heart rate is an independent risk factor for cardiovascular disease and a hemodynamic factor that can modulate blood flow as it affects the frequency of shear stimuli acting on the arterial wall. However, the association between heart rate and endothelium-dependent vasodilation remains highly controversial. We determined the association between heart rate at rest and endothelium-dependent vasodilation in 98 apparently healthy adults (18-63 years). The mild and positive association between heart rate and flow-mediated dilation (FMD) was no longer significant when age and sex or baseline diameter were controlled for. The path analyses revealed that heart rate was not directly related to FMD but the association was indirectly mediated by shear rate, which was confirmed by a bias-corrected bootstrap 95% CIs (0.0157-0.1056). We concluded that even though heart rate and endothelium-dependent vasodilation were associated with shear rate, there was no independent relation between heart rate and FMD.

The Role of Ivabradine in the Management of Angina Pectoris

Stable angina pectoris affects 2–4 % of the population in Western countries and entails an annual risk of death and nonfatal myocardial infarction of 1–2 % and 3 %, respectively. Heart rate (HR) is linearly related to myocardial oxygen consumption and coronary blood flow, both at rest and during stress. HR reduction is a key target for the prevention of ischemia/angina and is an important mechanism of action of drugs which are recommended as first line therapy for the treatment of angina in clinical guidelines. However, many patients are often unable to tolerate the doses of beta blocker or non-dihydropyridine calcium antagonists required to achieve the desired symptom control. The selective pacemaker current inhibitor ivabradine was developed as a drug for the management of patients with angina pectoris, through its ability to reduce HR specifically. The available data suggest that ivabradine is a well-tolerated and effective anti-anginal agent and it is recommended as a second-line agent for relief of angina in guidelines. However, recent clinical trials of ivabradine have failed to show prognostic benefit and have raised potential concerns about safety. This article will review the available evidence base for the current role of ivabradine in the management of patients with symptomatic angina pectoris in the context of stable coronary artery disease.

Effect of Heart Rate and Use of Beta Blockers on Mortality After Heart Transplantation

Heart transplantation (HT) recipients may have tachycardia secondary to cardiac denervation. As higher heart rate predicts worse outcomes in cardiovascular disease, we hypothesized that tachycardia and nonuse of β blockers are associated with increased mortality after HT. All patients who underwent HT at our institution from 1987 to 2010 were included. The association of heart rate 3 months after HT and β-blocker use during follow-up to mortality was assessed using Kaplan-Meier and multivariate Cox proportional hazards regression analyses adjusting for clinically relevant baseline variables. From 1987 to 2010, there were 493 HT. After excluding 29 who died within 3 months and 3 with follow-up <3 months, 461 HT recipients (50 ± 2 years; 20% women) were included. Over a follow-up of 12 ± 7 years, selected important univariate predictors of post-HT mortality were older age, male gender, higher body mass index, ischemic cardiomyopathy, longer post-HT intensive care unit stay, and hospitalization and at 3 months, increased mean pulmonary artery pressure, right atrial pressure and pulmonary capillary occlusion pressure, higher heart rate, and nonuse of β blockers during follow-up. In multivariate analysis, older ager, longer hospitalization, higher mean pulmonary artery pressure, higher heart rate at 3 months (hazard ratio 1.02 per beat, 95% confidence interval 1.008 to 1.035, p = 0.02) and nonuse of β blockers (hazard ratio 1.43, 95% confidence interval 1.002 to 2.031, p <0.05) were associated with mortality. In conclusion, in a large single-center cohort of HT recipients, higher heart rate and nonuse of β blockers were independently associated with higher mortality.

Intravascular hemodynamics and coronary artery disease: New insights and clinical implications

Intracoronary hemodynamics play a pivotal role in the initiation and progression of the atherosclerotic process. Low pro-inflammatory endothelial shear stress impacts vascular physiology and leads to the occurrence of coronary artery disease and its implications.

Associations of proteins relevant to MAPK signaling pathway (p38MAPK-1,HIF-1 and HO-1) with coronary lesion characteristics and prognosis of peri-menopausal women

BACKGROUND

The present study was intended to explore whether three proteins within MAPK signaling pathway (i.e. p38MAPK-1, HIF-1 and HO-1) were correlated with peri-menopausal women's coronary lesion features and prognosis.

METHODS

Altogether 1449 peri-menopausal women were divided into non-coronary artery disease (CAD) group (n = 860) and CAD group (n = 589), including 167 pre-menopausal CAD populations and 422 post-menopausal CAD populations. General information about CAD risk parameters were gathered, including age, family history of CAD or hypertension or diabetes mellitus, bilirubin, cholesterol, triglyceride, high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) and so on. Coronary angiography results were judged, and CAD score was calculated with application of Genisin scoring method. Besides, detection of MAPK-1 levels was implemented with Strept Avidin-Biotin Complex (SABC) method, while HIF-1 and HO-1 expressions in the serum were determined utilizing ELISA detection kit. Correlations among protein expressions, characteristics of coronary lesions and prognosis of CAD populations were finally evaluated.

RESULTS

Hypertension, hyperlipoidemia, diabetes and smoking history were more prevalent among postmenopausal CAD women than premenopausal CAD women (P < 0.05). Furthermore, postmenopausal women seemed to be significantly associated with multiple (i.e. double and triple) vessel lesions and severe lesion types (type B and C), when compared with premenopausal CAD group (P < 0.05). Similarly, remarkably elevated expressions of p38MAPK-1, HIF-1 and HO-1 were found within postmenopausal CAD populations in comparison to premenopausal ones (P < 0.05). The internal CysC, hs-CRP, TG and LDL-C concentrations all accorded with the following tendency: postmenopausal CAD women > premenopausal CAD women > non-CAD women. Moreover, p38MAPK-1, HIF-1 and HO-1 expressions were up-regulated with increasing number of vessel lesions and severity of coronary lesions among peri-menopausal women. Besides, among both pre-menopausal and post-menopausal CAD groups, positive correlations could be observed between MAPK-1 and TG (r _s = 0.271; r _s = 0.476), between HIF-1α and LDL-C (r _s = 0.077; r _s = 0.470), as well as between HO-1 and CysC (r _s = 0.492; r _s = 0.190) or hs-CRP (r _s = 0.569; r _s = 0.542) (all P < 0.05). MAPK-1, HIF-1α and HO-1 were also, respectively, positively correlated with CysC (r _s = 0.415), hs-CRP (r _s = 0.137), and TG (r _s = 0.142), regarding post-menopausal CAD women (all P < 0.05). Finally, only SBP and TG were regarded as independent risk factors for CAD prognosis (i.e. high Genisin score) among premenopausal women (OR = 1.02, 95%CI: 1.01-1.18, P = 0.043; OR = 1.82, 95%CI: 1.01-3.33, P = 0.047).

CONCLUSIONS

Expressions of p38MAPK-1, HIF-1 and HO-1 could serve as predictive roles for coronary lesions among peri-menopausal women.

Nonpharmacological Correction of Hypersympatheticotonia in Patients with Chronic Coronary Insufficiency and Severe Left Ventricular Dysfunction

BACKGROUND

Control of sympathetic hyperactivity is pivotal for treatment of heart failure (HF) in patients with coronary artery disease (CAD). Our earlier studies demonstrated that the auricular pulsed electrical stimulation of the vagus nerve (VNS) beneficially affected condition of CAD patients with HF. The aim of our study was to evaluate changes in heart rate (HR) and the levels of heat shock proteins in peripheral blood lymphocytes in patients with CAD in the course of VNS.

METHODS

The study comprised 70 individuals aged 50-68 years with chronic coronary insufficiency, severe left ventricular dysfunction, and NYHA functional class (FC) III-IV HF. Main group included 63 patients who received VNS course (group 1). Control patients (n = 7) received sham therapy (group 2).

RESULTS

According to the results of 6-minute walk test and 24-hour ECG monitoring, administration of VNS improved clinical condition of 58 of 63 patients, decreased HF FC, and attenuated HR. Clinical condition in sham therapy group did not change. Immunoenzyme method demonstrated that hsp70 and hsp60 contents in peripheral blood lymphocyte lysate increased by 58% and 48% (P < 0.05), respectively, in patients who initially had HR < 80 bpm. The hsp70 level significantly increased and hsp60 level remained unchanged in patients with initial HR > 80 bpm.

CONCLUSIONS

Correction of autonomous nervous status by VNS attenuated HR and improved functional state of the heart in CAD patients. Cardiotropic effect of VNS was the most pronounced in patients with preserved endogenous stress-limiting systems associated with hsp60 and/or hsp70.

Target organ damage in primary hypertensive patients: role of the morning heart rate surge

BACKGROUND

The morning heart rate surge (MHRS) and morning blood pressure surge (MBPS) may be responsible for the high prevalence of cardiovascular events during the morning period. The clinical significance of the MBPS has been well established, but that of the MHRS remains unclear. Thus, we evaluated the association between the MHRS and target organ damage (TOD).

METHODS

A cross-sectional study of 580 hypertensive patients was performed. MHRS and heart rate variability (HRV) were analyzed by 24 h electrocardiogram. TOD was assessed by estimated glomerular filtration rate, carotid intima-media thickness (IMT), and left ventricular mass index.

RESULTS

The prevalence of TOD tended to decrease with sleep-trough MHRS (first to fourth quartiles: 71%, 70.3%, 58.6%, and 52.7%, respectively) or prewaking MHRS quartiles (first to fourth quartiles: 65.3%, 73.6%, 61.4%, and 54.2%, respectively), whereas the opposite trend was observed for standard deviation of all normal NN intervals (SDNN). Moreover, sleep-trough MHRS, prewaking MHRS, SDNN, and SDNN index were significantly lower in patients with TOD than in those without TOD. According to four logistic regression models, the associations of prewaking MHRS, SDNN, and SDNN index with TOD were lost after adjustment for age and BP. Patients in the first (≤11.125 bpm) and second sleep-trough MHRS quartiles (11.125-15.75 bpm) had a 1.95-2.06-fold increased risk of TOD compared with those in the fourth quartile (p < 0.05).

CONCLUSION

A blunted sleep-trough MHRS, which may serve as a surrogate marker for autonomic imbalance, was independently associated with TOD in primary hypertensive patients.

Localizing factors in atherosclerosis

Atherosclerotic vascular disease is the leading cause of death worldwide. Although the entire vascular bed is constantly exposed to the same risk factors, atheromatous lesions present a distinct intra-individual pattern of localization and progression, being consistently more frequent in specific segments of the arterial vascular bed. This peculiar distribution may be related to selective sensitivity of such locations to the influence of risk factors or to histopathological and flow differences, and has relevant clinical implications, as the prognosis of the disease varies according to localization. We here review the theories that have been formulated to explain such preferential locations, as its understanding can be useful to pursue diagnostic screening strategies and focused preventive measures.

Associations between elevated resting heart rate and subclinical atherosclerosis in asymptomatic Korean adults undergoing coronary artery calcium scoring

Elevated resting heart rate (RHR) and the presence of coronary artery calcium (CAC) are closely related with inflammatory activity and cardiovascular disease outcomes. To date, however, the relationship between a high RHR and CAC has not been well studied, especially in non-western populations. We therefore aimed to examine the cross-sectional relationship between high RHR and the burden of subclinical atherosclerosis as measured by CAC score in a large sample of Korean adults. A total 26,018 subjects were enrolled and underwent CAC screening as part of a broader general health examination. RHR was categorized into four groups as: <60, 60-69, 70-79, and ≥80 beats per minute. Multivariable logistic regression models were employed to estimate the odds of having a CAC score of either >0, >100, or >400 based on RHR. Mean age of the study population was 53.9 ± 8.2 years, and 79.7 % were male. After adjustment, each 10 beat per minute increment in RHR was associated with greater odds of having a CAC score above 100 (OR 1.13, 95 % CI 1.08-1.18) or 400 (OR 1.22, 95 % CI 1.13-1.31). Likewise, following adjustment, the odds of having a CAC >100 or >400 for those with a RHR ≥80 beats per minute were 1.42 (95 % CI 1.19-1.69) and 1.86 (95 % CI 1.42-2.47), respectively, compared with those who had a RHR <60 beats per minute. In a large cohort of Korean adults, elevations in the RHR, particularly above 80 beats per minute, were found to be independently associated with the presence of subclinical atherosclerosis as measured by CAC scoring.

The Relationship Between Resting Heart Rate and SYNTAX Score in Patients With Stable Coronary Artery Disease

We investigated the relationship between resting heart rate (HR) and The Synergy between percutaneous coronary intervention with Taxus and cardiac surgery (SYNTAX) score in patients with stable coronary artery disease (SCAD). A total of 420 patients who were admitted to our outpatient clinic for stable angina pectoris with sinus rhythm and had at least 50% narrowing in at least 1 coronary artery after coronary angiography were included in the study. Patients were divided into 3 tertiles based on the resting HR: HR of tertile 1 was ≤65 (n = 138), tertile 2 was between 66 and 76 (n = 139), and tertile 3 was ≥77 beats/min (n = 143). The SYNTAX score (7.6 ± 4.6, 12.4 ± 5.6, 20.3 ± 8.1; P < .001) was significantly higher for those in tertile 3 than for those in tertiles 1 and 2. Leukocyte count (7.8 ± 2.2, 7.9 ± 2.2, 8.4 ± 2.3 × 109/L; P = .035) and C-reactive protein (CRP) levels (2.4 ± 0.5, 3.2 ± 0.7, 4.5 ± 1.2 mg/L, P < .001) were increasing from the lowest to the highest tertile. Using multiple logistic regression analysis, CRP (odds ratio [OR] 1.54 [1.17-2.11], P = .001) and resting HR (OR 1.67 [1.25-2.19], P < .001) emerged as independent predictors of SYNTAX score. Resting HR is related to SYNTAX score in patients with SCAD.

Cilostazol Enhances Mobilization of Circulating Endothelial Progenitor Cells and Improves Endothelium-Dependent Function in Patients at High Risk of Cardiovascular Disease

This is the first study to investigate the vasculoangiogenic effects of cilostazol on endothelial progenitor cells (EPCs) and flow-mediated dilatation (FMD) in patients at high risk of cardiovascular disease (CVD). This double-blind, placebo-controlled study included 71 patients (37 received 200 mg/d cilostazol and 34 received placebo for 12 weeks). Use of cilostazol, but not placebo, significantly increased circulating EPC (kinase insert domain receptor+CD34+) counts (percentage changes: 149.0% [67.9%-497.8%] vs 71.9% [−31.8% to 236.5%], P = .024) and improved triglyceride and high-density lipoprotein cholesterol levels ( P = .002 and P = .003, respectively). Plasma levels of vascular endothelial growth factor (VEGF)-A165 and FMD significantly increased (72.5% [32.9%-120.4%] vs −5.8% [−46.0% to 57.6%], P = .001; 232.8% ± 83.1% vs −46.9% ± 21.5%, P = .003, respectively) in cilostazol-treated patients. Changes in the plasma triglyceride levels significantly inversely correlated with the changes in the VEGF-A165 levels and FMD. Cilostazol significantly enhanced the mobilization of EPCs and improved endothelium-dependent function by modifying some metabolic and angiogenic markers in patients at high risk of CVD.

Cardiac Protective Effects of Moringa oleifera Seeds in Spontaneous Hypertensive Rats

BACKGROUND

Hypertension is characterized by a maintained high blood pressure leading to cardiac complications such as left ventricular hypertrophy and fibrosis and an increased risk of heart failure and myocardial infarction. This study investigated the cardiac effects of oral administration of Moringa oleifera (MOI) seed powder in spontaneous hypertensive rats (SHR).

METHODS

SHR received food containing MOI seed powder (750mg/d, 8 weeks) or normal food. In vivo measurement of hemodynamic parameters by telemetry and cardiac structure and function analysis by echocardiography were performed. Histological studies were performed to determine fibrosis and protein expression.

RESULTS

MOI treatment did not modify blood pressure in SHR but reduced nocturnal heart rate and improved cardiac diastolic function (reduction of isovolumetric relaxation time and deceleration time of the E wave, increase of ejection volume and cardiac output compared to nontreated SHR). Left ventricular anterior wall thickness, interseptal thickness on diastole, and relative wall thickness were reduced after MOI treatment. Furthermore, we found a significant reduction of fibrosis in the left ventricle of MOI-treated SHR. This antihypertrophic and antifibrotic effect of MOI was associated with increased expression of peroxisome proliferator-activated receptor (PPAR)-α and δ, reduced cardiac triglyceride level, and enhanced plasmatic prostacyclins.

CONCLUSIONS

Our data show a beneficial effect of MOI on the cardiac structure and function in SHR associated with an upregulation of PPAR-α and δ signaling. This study thus provides scientific rational support for the empirical use of MOI in the traditional Malagasy medicine against cardiac diseases associated with blood pressure overload.

An Early-Stage Atherosclerosis Research Model Based on Microfluidics

The arterial microenvironment plays a vital role in the pathology of atherosclerosis (AS). However, the interplay between the arterial microenvironment and atherogenesis remains unclear, partially due to the gap between cell culture and animal experiments. Addressing this problem, the present study reports a microfluidic AS model reconstituting early-stage AS. Physiological or AS-prone hemodynamic conditions are recapitulated on the model. The on-chip model recaptures the atherogenic responses of endothelial cells (ECs) in ways that the Petri dish could not. Significant cytotoxicity of a clinical anti-atherosclerotic drug probucol is discovered on the model, which does not appear on Petri dish but is supported by previous clinical evidence. Moreover, the anti-AS efficiency of platinum-nanoparticles (Pt-NPs) on the model shows excellent consistency with animal experiments. The early-stage AS model shows an excellent connection between Petri dish and animal experiments and highlights its promising role in bridging fundamental AS research, drug screening, and clinical trials.

The Association of Resting Heart Rate and Incident Hypertension: The Henry Ford Hospital Exercise Testing (FIT) Project

BACKGROUND

Given that sympathetic tone is associated with hypertension, we sought to determine whether resting heart rate (RHR), as a surrogate for cardiac autonomic function, was associated with incident hypertension.

METHODS

We analyzed 21,873 individuals without a history of hypertension who underwent a clinically indicated exercise stress test. Baseline RHR was assessed prior to testing and was categorized as <70, 70-85, and >85 beats-per-minute (bpm). Incident hypertension was defined by subsequent diagnosis codes for new-onset hypertension from three or more encounters. We tested for effect modification by age (<60 vs. ≥60 years), sex, race, and history of coronary heart disease (CHD).

RESULTS

Mean (±SD) age was 49 (±12) years, 55% were men and 21% were Black. Compared to the lowest RHR (<70 bpm) category, patients in the highest category (>85 bpm) were younger, more likely to be female, heavier, diabetic, and achieve lower metabolic equivalents (METS). Over a median of 4 years follow-up, there were 8,179 cases of incident hypertension. Compared to RHR <70 bpm, persons with RHR >85 bpm had increased risk of hypertension after adjustment for CHD risk factors, baseline blood pressure (BP), and METS (hazard ratio = 1.15 (95% confidence interval 1.08-1.23)). Age was an effect modifier (interaction P = 0.02), whereas sex, race, and CHD were not. In age-stratified analyses the relationship remained significant only in those younger than 60 years.

CONCLUSION

Elevated RHR is an independent risk factor for incident hypertension, particularly in younger persons. Whether lifestyle modification or other strategies to reduce RHR can prevent incident hypertension in high-risk individuals warrants further study.

Association of heart rate with albuminuria in a general adult population: the 2011 Korea National Health and Nutrition Examination Survey

BACKGROUND

Albuminuria is associated with increased risk of multiple adverse health outcomes, such as progressive renal failure, cardiovascular disease and death. However, in the general population, it is uncertain whether albuminuria is associated with elevated heart rate, which is an independent and powerful risk factor for cardiovascular disease.

AIM

To investigate whether an elevated heart rate is an independent factor associated with albuminuria in the general adult population of Korea.

METHODS

A cross-sectional analysis was carried out on 5198 Korean adults aged 19 years or older who participated in the fifth (2011) Korea National Health and Nutrition Examination Survey (KNHANES V-2).

RESULTS

The prevalence of albuminuria showed an increasing trend throughout the whole range of heart rate, even after adjusting for confounders (P = 0.002). The increment was most profound at the heart rate of 70-75 and >76 beats per minute (b.p.m.; P = 0.011). In multiple logistic regression analysis, age (P < 0.001), hypertension (P < 0.001), diabetes (P < 0.001), hypertriglyceridaemia (P = 0.025), estimated glomerular filtration rate (P = 0.028) and heart rate (P = 0.023) were independently associated with the presence of albuminuria in Korean adults. Compared with participants with heart rate ≤ 64 b.p.m., the odds ratio (95% CI) for albuminuria was 1.50 (1.15-1.96) for those with heart rate ≥ 76 b.p.m.

CONCLUSIONS

The prevalence of albuminuria is independently associated with heart rate in the general adult population of Korea.

Heart Rate Control With If Inhibitor, Ivabradine, in Japanese Patients With Chronic Heart Failure - A Randomized, Double-Blind, Placebo-Controlled Phase II Study

BACKGROUND

Elevated heart rate (HR) is an independent risk factor for cardiovascular outcomes in various cardiac diseases, including heart failure (HF).

METHODS AND RESULTS

Randomized placebo-controlled study was conducted to evaluate the effects of ivabradine, an Ifinhibitor, on the resting HR in 126 Japanese symptomatic HF patients with left ventricular ejection fraction ≤35%, resting HR ≥75 beats/min in sinus rhythm, and stable, optimal background treatment. Patients were randomly allocated into 3 groups: placebo; starting dose of ivabradine 2.5 mg twice daily (BID; 2.5 mg group); 5 mg BID group. The dose was increased up to 7.5 mg BID according to dose-adjustment criteria. After the 6-week treatment, the reductions in resting HR were significant in both the 2.5-mg (16.6±8.1 beats/min) and 5-mg (16.4±9.6 beats/min) groups (P<0.0001 for both groups) compared with placebo (1.7±8.7 beats/min). The most frequent side effect of ivabradine was phosphenes, but all were mild. Treatment was discontinued in 1 patient due to HF in the 5 mg group.

CONCLUSIONS

Ivabradine starting at 2.5 or 5 mg BID effectively reduced resting HR in Japanese HF patients. Ivabradine at the starting dose of 2.5 mg BID could be safer than 5 mg BID. (Circ J 2016; 80: 668-676).

Investigation of Tumor Cell Behaviors on a Vascular Microenvironment-Mimicking Microfluidic Chip

The extravasation of tumor cells is a key event in tumor metastasis. However, the mechanism underlying tumor cell extravasation remains unknown, mainly hindered by obstacles from the lack of complexity of biological tissues in conventional cell culture, and the costliness and ethical issues of in vivo experiments. Thus, a cheap, time and labor saving, and most of all, vascular microenvironment-mimicking research model is desirable. Herein, we report a microfluidic chip-based tumor extravasation research model which is capable of simultaneously simulating both mechanical and biochemical microenvironments of human vascular systems and analyzing their synergistic effects on the tumor extravasation. Under different mechanical conditions of the vascular system, the tumor cells (HeLa cells) had the highest viability and adhesion activity in the microenvironment of the capillary. The integrity of endothelial cells (ECs) monolayer was destroyed by tumor necrosis factor-α (TNF-α) in a hemodynamic background, which facilitated the tumor cell adhesion, this situation was recovered by the administration of platinum nanoparticles (Pt-NPs). This model bridges the gap between cell culture and animal experiments and is a promising platform for studying tumor behaviors in the vascular system.

FSI SIMULATION OF A HEALTHY CORONARY BIFURCATION FOR STUDYING THE MECHANICAL STIMULI OF ENDOTHELIAL CELLS UNDER DIFFERENT PHYSIOLOGICAL CONDITIONS

Atherosclerosis is a world-spread and well-known disease. This disease strongly relates to the endothelial cells (ECs) function. Normally, the endothelial cells align in the flow direction in the atheroprotected sites; however, in the case of atheroprone sites these cells orient randomly. The mechanical stimuli such as wall shear stress and strains could determine the morphology and function of the endothelial cells. In the present study, we numerically simulated the left main coronary artery (LCA) and its branches to left anterior descending (LAD) and left circumflex coronary (LCX) artery using fluid–structure interaction (FSI) modeling. The results were presented as longitudinal and circumferential strains of ECs as well as wall shear stress. Wide ranges of heart rate, cardiac motion, systolic and diastolic pressures were considered and their effects on mechanical stimuli were described in detail. The results showed that these factors could greatly influence the risk of atherosclerosis and the location of atherosclerotic lesions.

Determinants of All-Cause Mortality and Incidence of Cardiovascular Disease (2009 to 2013) in Older Adults

Aim:

Ikaria Island (North-East Aegean, Greece) has been recognized as one of the places with the highest life expectancy around the world (the Blues Zones). Risk factors in relation to 4-year all-cause mortality and cardiovascular disease (CVD) incidence in elders were studied.

Methods:

From June to October 2009, 330 men and 343 women, aged 65 to 100 years, were enrolled, and in June to July 2013, they were reevaluated.

Results:

Age-standardized, gender-specific, all-cause mortality rate was 790 deaths per 10 000 inhabitants, and causes of death were CVD (36%), cancer (21%), infection (10%), respiratory disease (2%), and other (31%). Incidence of CVDwas 520 cases per 10 000 men inhabitants and 320 cases per 10 000 women ( P = .03). Age, male gender, heart rate, urea levels, left atrial maximum volume, left ventricular hypertrophy, thyroid-stimulating hormone, and moderate to severe depression were positively associated with mortality, whereas left ventricular ejection fraction as well as coffee and tea drinking, fruit intake, and exclusive olive oil use were inversely associated with CVD.

Conclusion:

Heart function markers in addition to antioxidant dietary factors were placed in this puzzle of CVD morbidity.

Homocysteine, Ischemic Stroke, and Coronary Heart Disease in Hypertensive Patients

Background and Purpose—

Total homocysteine level (tHcy) is a risk factor of ischemic stroke (IS) and coronary heart disease. However, the results are conflicting and mainly focused on healthy individuals in developed countries.

Methods—

A prospective, population-based cohort study was conducted among 5935 participants from 60 communities in the city of Shenzhen, China. A Cox regression analysis was applied to evaluate the contribution of tHcy to the risk of IS and coronary heart disease. The effect of folic acid supplementation on tHcy levels was also evaluated among 501 patients with essential hypertension, who received an average of 2.5 years of folic acid supplementation.

Results—

After adjustment for confounding factors, the hazard ratios (95% confidence intervals) of IS caused by hyperhomocysteinemia were 2.18 (1.65–2.89), 2.40 (1.56–3.67), and 2.73 (1.83–4.08) in the total, male, and female participants, respectively. Compared with normal levels of tHcy (<15 μmol/L), the hazard ratios (95% confidence intervals) for IS in the highest tHcy category (≥30 μmol/L) were 4.96 (3.03–8.12), 6.11 (3.44–10.85), and 1.84 (0.52–6.46) in the total, males, and females participants, respectively. However, we did not observe a significant relationship between tHcy and the risk of coronary heart disease. The 2.5 years of folic acid supplementation reduced tHcy levels by 6.7 μmol/L (27.92%) in patients with essential hypertension.

Conclusions—

Hyperhomocysteinemia in Chinese hypertensive patients is significantly associated with IS risk but not coronary heart disease susceptibility, and folic acid supplementation can efficiently reduce tHcy levels.

Resting heart rate: risk indicator and emerging risk factor in cardiovascular disease

Resting heart rate is central to cardiac output and is influenced by changes occurring in numerous diseases. It predicts longevity and cardiovascular diseases, and current evidence suggests that it is also an important marker of outcome in cardiovascular disease, including heart failure. Beta-blockers improve outcomes in heart failure; however, they have effects outside reducing heart rate. Ivabradine has demonstrated efficacy in reducing rehospitalizations and mortality in heart failure and in improving exercise tolerance and reducing angina attacks in patients with coronary artery disease, whereas selective heart rate reduction may also prove to be beneficial in therapeutic areas outside those in which ivabradine has already demonstrated clinical efficacy. This review provides an update on the associations between heart rate and cardiovascular outcomes in various conditions, the experimental effects of heart rate reduction with ivabradine, and the potential new indications in cardiovascular disease.

Vigorous physical activity and carotid distensibility in young and mid-aged adults

Although physical activity (PA) improves arterial distensibility, it is unclear which type of activity is most beneficial. We aimed to examine the association of different types of PA with carotid distensibility (CD) and the mechanisms involved. Data included 4503 Australians and Finns aged 26-45 years. Physical activity was measured by pedometers and was self-reported. CD was measured using ultrasound. Other measurements included resting heart rate (RHR), cardiorespiratory fitness (CRF), blood pressure, biomarkers and anthropometry. Steps/day were correlated with RHR (Australian men r = -0.10, women r = - 0.14; Finnish men r = -0.15, women r = -0.11; P<0.01), CRF and biochemical markers, but not with CD. Self-reported vigorous leisure-time activity was more strongly correlated with RHR (Australian men r = -0.23, women r = -0.19; Finnish men r = -0.20, women r = -0.13; P < 0.001) and CRF, and was correlated with CD (Australian men r = 0.07; Finnish men r = 0.07, women r = 0.08; P < 0.05). This relationship of vigorous leisure-time activity with CD was mediated by RHR independently of potential confounders. In summary, vigorous leisure-time PA but not total or less intensive PA was associated with arterial distensibility in young to mid-aged adults. Promotion of vigorous PA is therefore recommended among this population. RHR was a key intermediary factor explaining the relationship between vigorous PA and arterial distensibility.

Associations of daytime, nighttime, and 24-hour heart rate with four distinct markers of inflammation in hypertensive patients: the Styrian Hypertension Study

The current study assessed which measure of heart rate (HR) is most associated with inflammatory activity. Among 368 hypertensive patients (mean age±standard deviation, 60.6±10.8; 52.9% women), mean daytime (from 6 am to 10 pm), nighttime (from 10 pm to 6 am), and 24-hour HR were recorded using a continuous 24-hour ambulatory blood pressure monitoring portable device. Associations of daytime, nighttime, and 24-hour HR with leukocytes, platelets, C-reactive protein (CRP), and 25-hydroxyvitamin D were calculated using multivariate linear regression, reporting unstandardized coefficients (B) with standard errors (SEs). Mean daytime, nighttime, and 24-hour HR were 73, 64, and 71 beats per minute, respectively. All HR measures were positively associated with leukocytes after adjustment. Nighttime HR was additionally related with higher CRP. When all HR measures were simultaneously added to a single multivariate model, only the positive associations of nighttime HR with leukocytes (B [SE]=0.06 [0.03], P=.04), as well as with CRP (B [SE]=0.20 [0.07], P=.005), persisted. Nighttime HR was more closely associated with inflammatory activity. These observations lend some insight toward the pathophysiological mechanisms that implicate HR in cardiovascular risk and provide valuable direction for forthcoming investigations.

Resting heart rate in first year survivors of myocardial infarction and long-term mortality: a community study

OBJECTIVE

To evaluate the long-term prognostic effect of resting heart rate (HR) at index myocardial infarction (MI) and during the first year after MI among 1-year survivors.

PATIENTS AND METHODS

The community-based cohort consisted of 1571 patients hospitalized with an incident MI from January 1, 1983, through December 31, 2007, in Olmsted County, Minnesota, who were in sinus rhythm at index MI and had HR measurements on electrocardiography at index and during the first year after MI. Outcomes were all-cause and cardiovascular deaths.

RESULTS

During a median follow-up of 7.0 years, 627 deaths and 311 cardiovascular deaths occurred. Using patients with HRs of 60/min or less as the referent, this study found that long-term all-cause mortality risk increased progressively with increasing HR at index (hazard ratio, 1.62; 95% CI, 1.25-2.09) and even more with increasing HR during the first year after MI (hazard ratio, 2.16; 95% CI, 1.64-2.84) for patients with HRs greater than 90/min, adjusting for clinical characteristics and β-blocker use. Similar results were observed for cardiovascular mortality (adjusted hazard ratio, 1.66; 95% CI, 1.14-2.42; and adjusted hazard ratio, 1.93; 95% CI, 1.27-2.94; for HR at index and within 1 year after MI, respectively).

CONCLUSION

These data from a large MI community cohort indicate that HR is a strong predictor of long-term all-cause and cardiovascular mortality not only at initial presentation of MI but also during the first year of follow-up.

Physical activity and resting pulse rate in older adults: findings from a randomized controlled trial

BACKGROUND

Elevated resting pulse rate (RPR) is a well-recognized risk factor for adverse outcomes. Epidemiological evidence supports the beneficial effects of regular exercise for lowering RPR, but studies are mainly confined to persons younger than 65 years. We set out to evaluate the utility of a physical activity (PA) intervention for slowing RPR among older adults.

METHODS

A total of 424 seniors (ages 70-89 years) were randomized to a moderate intensity PA intervention or an education-based "successful aging" health program. Resting pulse rate was assessed at baseline, 6 months, and 12 months. Longitudinal differences in RPR were evaluated between treatment groups using generalized estimating equation models, reporting unstandardized β coefficients with robust SEs.

RESULTS

Increased frequency and duration of aerobic training were observed for the PA group at 6 and 12 months as compared with the successful aging group (P < .001). In both groups, RPR remained unchanged over the course of the 12-month study period (P = .67). No significant improvement was observed (β [SE] = 0.58 [0.88]; P = .51) for RPR when treatment groups were compared using the generalized estimating equation method. Comparable results were found after omitting participants with a pacemaker, cardiac arrhythmia, or who were receiving β-blockers.

CONCLUSIONS

Twelve months of moderate intensity aerobic training did not improve RPR among older adults. Additional studies are needed to determine whether PA of longer duration and/or greater intensity can slow RPR in older persons.

The J-curve in arterial hypertension: fact or fallacy?

It is known that a large proportion of patients with arterial hypertension are undertreated. This may result in an increase of the incidence of cardiovascular events. On the other hand, aggressive reduction of blood pressure may increase cardiovascular events (J-curve phenomenon) in certain populations. This phenomenon may be seen in patients with coronary artery disease and left ventricular hypertrophy when the diastolic blood pressure decreases below 70-80 mm Hg, and the systolic blood pressure decreases below 130 mm Hg. This phenomenon is not seen in patients with stroke or renal disease. Thus, a safer and more conservative strategy should be applied in patients with coronary artery disease, left ventricular hypertrophy, elderly, and in patients with isolated systolic hypertension. This is depicted in the recently published European Society of Hypertension/European Society of Cardiology guidelines in which higher targets of blood pressure are suggested in certain cardiovascular diseases and in the elderly.

Ivabradine, coronary artery disease, and heart failure: beyond rhythm control

Elevated heart rate could negatively influence cardiovascular risk in the general population. It can induce and promote the atherosclerotic process by means of several mechanisms involving endothelial shear stress and biochemical activities. Furthermore, elevated heart rate can directly increase heart ischemic conditions because of its skill in unbalancing demand/supply of oxygen and decreasing the diastolic period. Thus, many pharmacological treatments have been proposed in order to reduce heart rate and ameliorate the cardiovascular risk profile of individuals, especially those suffering from coronary artery diseases (CAD) and chronic heart failure (CHF). Ivabradine is the first pure heart rate reductive drug approved and currently used in humans, created in order to selectively reduce sinus node function and to overcome the many side effects of similar pharmacological tools (ie, β-blockers or calcium channel antagonists). The aim of our review is to evaluate the role and the safety of this molecule on CAD and CHF therapeutic strategies.

Association between resting heart rate across the life course and all-cause mortality: longitudinal findings from the Medical Research Council (MRC) National Survey of Health and Development (NSHD)

BACKGROUND

Resting heart rate (RHR) is an independent risk factor for mortality. Nevertheless, it is unclear whether elevations in childhood and mid-adulthood RHR, including changes over time, are associated with mortality later in life. We sought to evaluate the association between RHR across the life course, along with its changes and all-cause mortality.

METHODS

We studied 4638 men and women from the Medical Research Council (MRC) National Survey of Health and Development (NSHD) cohort born during 1 week in 1946. RHR was obtained during childhood at ages 6, 7 and 11, and in mid-adulthood at ages 36 and 43. Using multivariable Cox regression, we calculated the HR for incident mortality according to RHR measured at each time point, along with changes in mid-adulthood RHR.

RESULTS

At age 11, those in the top fifth of the RHR distribution (≥97 bpm) had an increased adjusted hazard of 1.42 (95% CI 1.04 to 1.93) for all-cause mortality. A higher adjusted risk (HR, 95% CI 2.17, 1.40 to 3.36) of death was also observed for those in the highest fifth (≥81 bpm) at age 43. For a >25 bpm increased change in the RHR over the course of 7 years (age 36-43), the adjusted hazard was elevated more than threefold (HR, 95% CI 3.26, 1.54 to 6.90). After adjustment, RHR at ages 6, 7 and 36 were not associated with all-cause mortality.

CONCLUSIONS

Elevated RHR during childhood and midlife, along with greater changes in mid-adulthood RHR, are associated with an increased risk of all-cause mortality.

Long-term cardiovascular risks associated with an elevated heart rate: the Framingham Heart Study

BACKGROUND

Higher heart rate has been associated with an adverse prognosis, but most prior studies focused on individuals with known cardiovascular disease or examined a limited number of outcomes. We sought to examine the association of baseline heart rate with both fatal and nonfatal outcomes during 2 decades of follow-up.

METHODS AND RESULTS

Our study included 4058 Framingham Heart Study participants (mean age 55 years, 56% women). Cox models were performed with multivariable adjustment for clinical risk factors and physical activity. A total of 708 participants developed incident cardiovascular disease (303 heart failure, 343 coronary heart disease, and 216 stroke events), 48 received a permanent pacemaker, and 1186 died. Baseline heart rate was associated with incident cardiovascular disease (hazard ratio [HR] 1.15 per 1 SD [11 bpm] increase in heart rate, 95% CI 1.07 to 1.24, P=0.0002), particularly heart failure (HR 1.32, 95% CI 1.18 to 1.48, P<0.0001). Higher heart rate was also associated with higher all-cause (HR 1.17, 95% CI 1.11 to 1.24, P<0.0001) and cardiovascular mortality (HR 1.18, 95% CI 1.04 to 1.33, P=0.01). Spline analyses did not suggest a lower threshold beyond which the benefit of a lower heart rate abated or increased. In contrast, individuals with a higher heart rate had a lower risk of requiring permanent pacemaker placement (HR 0.55, 95% CI 0.38 to 0.79, P=0.001).

CONCLUSIONS

Individuals with a higher heart rate are at elevated long-term risk for cardiovascular events, in particular, heart failure, and all-cause death. On the other hand, a higher heart rate is associated with a lower risk of future permanent pacemaker implantation.

Initial heart rate and cardiovascular outcomes in patients presenting with acute coronary syndrome

OBJECTIVES

To assess the impact of on-admission heart rate (HR) in patients presenting with acute coronary syndrome (ACS).

METHODS

Data were collected retrospectively from the second Gulf Registry of Acute Coronary Events. Patients were divided according to their initial HR into: (I: < 60, II: 60-69, III: 70-79, IV: 80-89 and V: ≥ 90 bpm). Patients' characteristics and hospital and one- and 12-month outcomes were analyzed and compared.

RESULTS

Among 7939 consecutive ACS patients, groups I to V represented 7%, 13%, 20%, 23.5%, and 37%, respectively. Mean age was higher in groups I and V. Group V were more likely males, diabetic and hypertensive. ST-elevation myocardial infarction was the main presentation in groups I and V. Reperfusion therapies were less likely given to group V. Beta blockers were more frequently prescribed to group III in comparison to groups with higher HR. Groups I and V were associated with worse hospital outcomes. Multivariate analysis showed initial tachycardia as an independent predictor for heart failure (OR 2.2; 95%CI: 1.39-3.32), while bradycardia was independently associated with higher one-month mortality (OR 2.0; 95%CI: 1.04-3.85) CONCLUSION: The majority of ACS patients present with tachycardia. However, low or high HR is a marker of high risk that needs more attention and management.