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

Impact of Functional Mitral Regurgitation on Left Ventricular Strain in Nonischemic Dilated Cardiomyopathy Patients with Type 2 Mellitus Diabetes: A Magnetic Resonance Feature Tracking Study

BACKGROUND

The impact of functional mitral regurgitation and type 2 mellitus diabetes (T2DM) on left ventricular (LV) strain in nonischemic dilated cardiomyopathy (NIDCM) patients remains unclear.

PURPOSE

To evaluate the impact of mitral regurgitation severity on LV strain, and explore additive effect of T2DM on LV function across varying mitral regurgitation severity levels in NIDCM patients.

STUDY TYPE

Retrospective.

POPULATION

352 NIDCM (T2DM-) patients (49.1 ± 14.6 years, 67% male) (207, 85, and 60 no/mild, moderate, and severe mitral regurgitation) and 96 NIDCM (T2DM+) patients (55.2 ± 12.4 years, 77% male) (47, 30, and 19 no/mild, moderate, and severe mitral regurgitation).

FIELD STRENGTH/SEQUENCE

3.0 T/balanced steady-state free precession sequence.

ASSESSMENT

LV geometric parameters and strain were measured and compared among groups. Determinants of LV strain were investigated.

STATISTICAL TEST

Student's t-test, Mann-Whitney U test, one-way ANOVA, Kruskal-Wallis test, univariable and multivariable linear regression. P < 0.05 was considered statistically significant.

RESULTS

LV GLPS and longitudinal PDSR decreased gradually with increasing mitral regurgitation severity in NIDCM patients with T2DM(GLPS: -5.7% ± 2.1% vs. -4.3% ± 1.6% vs. -2.6% ± 1.3%; longitudinal PDSR:0.5 ± 0.2 sec-1 vs. 0.4 ± 0.2 sec-1 vs. 0.3 ± 0.1 sec-1). NIDCM (T2DM+) demonstrated decreased GCPS and GLPS in the no/mild subgroup, reduced LV GCPS, GLPS, and longitudinal PDSR in the moderate subgroup, and reduced GRPS, GCPS, GLPS, and longitudinal PDSR in the severe subgroup compared with NIDCM (T2DM-) patients. Multivariable regression analysis identified that mitral regurgitation severity (β = -0.13, 0.15, and 0.25 for GRPS, GCPS, and GLPS) and the presence of T2DM (β = 0.14 and 0.13 for GCPS and GLPS) were independent determinants of LV strains in NIDCM patients.

DATA CONCLUSION

Increased mitral regurgitation severity is associated with reduced LV strains in NIDCM patients with T2DM. The presence of T2DM exacerbated the decline of LV function across various mitral regurgitation levels in NIDCM patients, resulting in reduced LV strains.

LEVEL OF EVIDENCE: 3

TECHNICAL EFFICACY

Stage 3.

Reference ranges for ambulatory heart rate measurements in a middle-aged population

BACKGROUND

Elevated heart rate (HR) predicts cardiovascular disease and mortality, but there are no established normal limits for ambulatory HR. We used data from the Swedish CArdioPulmonary Imaging Study to determine reference ranges for ambulatory HR in a middle-aged population. We also studied clinical correlates of ambulatory HR.

METHODS

A 24-hour ECG was registered in 5809 atrial fibrillation-free individuals, aged 50-65 years. A healthy subset (n=3942) was used to establish reference values (excluding persons with beta-blockers, cardiovascular disease, hypertension, heart failure, anaemia, diabetes, sleep apnoea or chronic obstructive pulmonary disease).Minimum HR was defined as the lowest 1-minute HR. Reference ranges are reported as means±SDs and 2.5th-97.5th percentiles. Clinical correlates of ambulatory HR were analysed with multivariable linear regression.

RESULTS

The average mean and minimum HRs were 73±9 and 48±7 beats per minute (bpm) in men and 76±8 and 51±7 bpm in women; the reference range for mean ambulatory HR was 57-90 bpm in men and 61-92 bpm in women. Average daytime and night-time HRs are also reported. Clinical correlates, including age, sex, height, body mass index, physical activity, smoking, alcohol intake, diabetes, hypertension, haemoglobin level, use of beta-blockers, estimated glomerular filtration rate, per cent of predicted forced expiratory volume in 1 s and coronary artery calcium score, explained <15% of the interindividual differences in HR.

CONCLUSION

Ambulatory HR varies widely in healthy middle-aged individuals, a finding with relevance for the management of patients with a perception of tachycardia. Differences in ambulatory HR between individuals are largely independent of common clinical correlates.

The clinical value of β-blockers in patients with stable angina

Stable angina, one manifestation of chronic coronary syndrome (CCS), is characterised by intermittent episodes of insufficient blood supply to the myocardium, provoking symptoms of myocardial ischaemia, particularly chest pain. These attacks usually occur during exercise or stress. Anti-ischaemic drugs are the mainstay of pharmacologic management of CCS with symptoms of angina. β-blockers reduce heart rate and myocardial contractility, thus reducing myocardial oxygen consumption. These drugs have been shown to ameliorate the frequency of anginal attacks and to improve exercise capacity in these patients. Current management guidelines include β-blockers as a first-line management option for most patients with CCS and symptoms of myocardial ischaemia, alongside dihydropyridine calcium channel blockers (CCB). The presence of comorbid angina and heart failure is a strong indication for starting with a β-blocker. β-blockers are also useful in the management of angina symptoms accompanied by a high heart rate, hypertension (with or without a renin-angiotensin-aldosterone-system [RAS] blocker or CCB), or microvascular angina (with a RAS blocker and a statin). A β-blocker is not suitable for a patient with low heart rate (<50 bpm), although use of a β-blocker may be supported by a pacemaker if the β-blocker is strongly indicated) and should be used at a low dose only in patients with low blood pressure.

Heart rate: an accessible risk indicator in adult congenital heart disease

BACKGROUND

Higher resting heart rate has been described as a risk factor for adverse outcome in healthy individuals and cardiovascular patients. The aim of this study was to evaluate resting heart rate as risk factor in adult congenital heart disease (ACHD).

METHODS

In this prospective observational cohort study, patients with moderate or complex ACHD were included at routine outpatient visit. Standard 12-lead ECGs were obtained in rest. Heart rate was obtained from the ECG automatically by the Modular ECG Analysis System (MEANS). The primary endpoint was all-cause mortality and the secondary endpoint was a composite of all-cause mortality and heart failure. Survival was derived using the Kaplan-Meier estimator. Subgroups based on heart rate tertiles were compared by the log-rank test. Cox proportional hazards models were adjusted for clinical factors including age, sex and diagnosis (moderate vs complex ACHD).

RESULTS

A total of 556 patients were included (median age 32 years (IQR 24-41), 57.6% male). Mean heart rate was 69±13 bpm. Negative chronotropic medication was used by 74 (13.3%) patients. During a median follow-up of 10.1 (IQR 9.6-10.5) years, 36 patients (6.5%) died and 83 (14.9%) reached the secondary endpoint. Patients with higher heart rates had significantly lower survival and heart failure-free survival. After adjusting for clinical factors, heart rate remained associated with mortality (HR 1.57 per 10 bpm, 95% CI 1.26 to 1.96) and mortality or heart failure (HR 1.33 per 10 bpm, 95% CI 1.13 to 1.57).

CONCLUSION

Higher heart rate is associated with lower survival and heart failure-free survival in ACHD.

Added value of arterial stiffness index for the 10-year atherosclerotic cardiovascular disease risk determination in a middle-aged population-based study

OBJECTIVE

Atherosclerotic cardiovascular disease (ASCVD) is considered the leading cause of mortality worldwide. Arterial stiffness, measured by arterial stiffness index (ASI), could be a main predictor in target damage of organs. Uncertainty remains regarding the contribution of ASI to estimated ASCVD risk. This study investigates the added value of ASI in ASCVD risk determination using the general UK Biobank middle-aged population.

METHODS

Among 100,598 participants from the UK Biobank population, ASI was assessed and associations between ASCVD risk were stratified by sex and estimated using multiple linear and logistic regressions adjusted for heart rate, physical activity, alcohol status, smocking pack years, BMI categories and CKD.

RESULTS

Males presented higher ASCVD risk than females (8.58% vs. 2.82%, p < 0.001) and higher ASI levels (9.50 m/s vs. 7.00 m/s, p < 0.001). The Youden index was determined at 9.70 m/s in males (p < 0.001) and 10.46 m/s in females (p < 0.001). Among females, participants with ASI > 10.46 m/s showed higher ASCVD risk than others (3.64% vs. 2.56%, p < 0.001), similar results were observed for males (9.92% vs. 7.21%, p < 0.001). In males, ASI showed significant added value information when including overall covariates (AUC = 0.695 vs. AUC = 0.663, p < 0.001). Similar results were observed in females (AUC = 0.693 vs. AUC = 0.687, p = 0.001). In both genders, for the association between ASI and ASCVD risk, nonlinear relationships were observed with higher accuracies than linear models.

CONCLUSION

Further studies should investigate ASCVD risk stratification management depending on ASI measurement.

Association of cumulative resting heart rate exposure with rapid renal function decline: a prospective cohort study with 27,564 older adults

OBJECTIVE

To evaluate the prospective association between cumulative resting heart rate (cumRHR) and rapid renal function decline (RRFD) in a cohort of individuals aged 60 and older.

METHODS

In the Tianjin Chronic Kidney Disease Cohort Study, the individuals who underwent three consecutive physical examinations between 2014 and 2017, with estimated glomerular filtration rate (eGFR) greater than 60 mL/min per 1.73 m2 and aged 60 years or older were enrolled. A total of 27,564 patients were prospectively followed up from January 1, 2017 to December 31, 2020. The 3-year cumRHR was calculated. The primary outcome was RRFD, defined as an annualized decline in eGFR of 5 mL/min per 1.73 m2 or greater. Logistic and restricted spline regression models and subgroup analysis were used to investigate the association of cumRHR with RRFD after adjusting for all confounders.

RESULTS

During a median follow-up of 3.2 years, a total of 4,347 (15.77%) subjects developed RRFD. In fully-adjusted models, compared with the lowest quartile of cumRHR, the odds ratio (OR) for the highest was 1.44 (1.28-1.61), P < 0.001. Furthermore, each 1-standard deviation (27.97 beats/min per year) increment in cumRHR was associated with a 17% (P < 0.001) increased risk of RRFD, with a linear positive correlation (P for non-linear = 0.803). Participants with a 3-year cumRHR ≥ 207 (beats/min) * year (equivalent to ≥ 69 beats/min per year in 3 years) were found to be at a higher risk of RRFD.

CONCLUSIONS

The cumRHR is significantly associated with a higher risk of RRFD among older adults. These results might provide an effective goal for managing and delaying the decline of renal function in the older adults.

Autonomic dysfunction is associated with the development of arterial stiffness: the Whitehall II cohort

This study aims to examine the association between baseline level and change of autonomic nervous function with subsequent development of arterial stiffness. Autonomic nervous function was assessed in 4901 participants of the Whitehall II occupational cohort by heart rate variability (HRV) indices and resting heart rate (rHR) three times between 1997 and 2009, while arterial stiffness was assessed by carotid-femoral pulse wave velocity (PWV) measured twice between 2007 and 2013. First, individual HRV/rHR levels and annual changes were estimated. Then, we modelled the development of PWV by HRV/rHR using linear mixed effect models. First, we adjusted for sex and ethnicity (model 1), and then for socioeconomic and lifestyle factors, various clinical measurements, and medications (model 2). A decrease in HRV and unchanged rHR was associated with subsequent higher levels of PWV, but the effect of a change in HRV was less pronounced at higher ages. A typical individual aged 65 years with a SDNN level of 30 ms and a 2% annual decrease in SDNN had 1.32 (0.95; 1.69) higher PWV compared to one with the same age and SDNN level but with a 1% annual decrease in SDNN. Further adjustment had no major effect on the results. People who experience a steeper decline in autonomic nervous function have higher levels of arterial stiffness. The association was stronger in younger people.

Apoe-knockout induces strong vascular oxidative stress and significant changes in the gene expression profile related to the pathways implicated in redox, inflammation, and endothelial function

Apolipoprotein E (APOE) was recognized as a key regulator of lipid metabolism, which prompted the Apoe-knockout (Apoe^-/-) mouse to be the most widely used atherosclerotic model. However, with more and more important physiological roles of APOE being revealed, it is necessary to reacquaint its comprehensive function in the aorta. In this study, we aimed to reveal how Apoe-knockout impacts the gene pathways and phenotypes in the aorta of mice. We performed transcriptome sequencing to acquire the gene expression profile (GEP) for C57BL/6J and Apoe^-/- mouse aorta, and used enrichment analysis to reveal the signal pathways enriched for differentially expressed genes (DEGs). In addition, we used immunofluorescence and ELISA to detect the phenotypic differences of vascular tissues and plasma in the two-group mice. Apoe-knockout resulted in significant changes in the expression of 538 genes, among which about 75% were up-regulated and 134 genes were altered more than twice. In addition to the lipid metabolism pathways, DEGs were also mainly enriched in the pathways implicated in endothelial cell proliferation, migration of epithelial cells, immune regulatory, and redox. GSEA shows that the up-regulated genes are mainly enriched in 'immune regulation pathways' and 'signal regulation' pathways, while the down-regulated genes are enriched in lipid metabolism pathways, 'regulation_of_nitric_oxide_synthase_activity' and the pathways involved in redox homeostasis, including 'monooxygenase regulation', 'peroxisomes' and 'oxygen binding'. A significant increase of reactive oxygen species and a remarkable reduction of GSH/GSSG ratio were respectively observed in the vascular tissues and plasma of Apoe^-/- mice. In addition, endothelin-1 significantly increased in the vascular tissue and the plasma of Apoe^-/- mice. Taken together, our results suggest that besides functioning in lipid metabolism, APOE may be an important signal regulator that mediates the expression of the genes related to the pathways involved in redox, inflammation, and endothelial function. Apoe-knockout-induced strong vascular oxidative stress is also the key factor contributing to atherosclerosis.

The controversial role of beta-blockers in heart failure with preserved ejection fraction

Beta-blocker (BB) therapy is a main pillar in treating patients with heart failure and reduced ejection fraction and has shown a prognostic benefit. However, evidence for application of BB in heart failure with preserved ejection fraction (HFpEF), especially in the absence of coronary artery disease, atrial fibrillation or arterial hypertension, is scarce. HFpEF is characterized by elevations in left atrial pressure and reduced compliance of the left ventricle leading to a hampered increase of cardiac output (CO) during exercise, which results in exertional dyspnea. This may be due to either a limited increase in stroke volume or reduced chronotropy during physical activity. We critically discuss the pathophysiological background of HFpEF, current data on BB in heart failure therapy, as well as the potential benefits and harms of BB therapy in HFpEF. Furthermore, we argue that non-cardio selective BB with peripheral activity to reduce afterload may be more suitable in this population than cardio-selective BB. Although preliminary data on BB in HFpEF are available, multicenter prospective trials to assess a reduction of cardiovascular morbidity are warranted. Future trials need to focus on phenotyping HFpEF patients and assess who may benefit most from tailored BB therapy.

Minimum heart rate and mortality after cardiac surgery: retrospective analysis of the Multi-parameter Intelligent Monitoring in Intensive Care (MIMIC-III) database

Low heart rate is a risk factor of mortality in many cardiovascular diseases. However, the relationship of minimum heart rate (MHR) with outcomes after cardiac surgery is still unclear, and the association between optimum MHR and risk of mortality in patients receiving cardiac surgery remains unknown. In this retrospective study using the Multi-parameter Intelligent Monitoring in Intensive Care (MIMIC-III) database, 8243 adult patients who underwent cardiac surgery were included. The association between MHR and the 30-day, 90-day, 180-day, and 1-year mortality of patients undergoing cardiac surgery was analyzed using multivariate Cox proportional hazard analysis. As a continuous variable, MHR was evaluated using restricted cubic regression splines, and appropriate cut-off points were determined. Kaplan-Meier curve was used to further explore the relationship between MHR and prognosis. Subgroup analyses were performed based on age, sex, hypertension, diabetes, and ethnicity. The rates of the 30-day, 90-day, 180-day, and 1-year mortalities of patients in the low MHR group were higher than those in the high MHR group (4.1% vs. 2.9%, P < 0.05; 6.8% vs. 5.3%, P < 0.05; 8.9% vs. 7.0%, P < 0.05, and 10.9% vs. 8.8%, P < 0.05, respectively). Low MHR significantly correlated with the 30-day, 90-day, 180-day, and 1-year mortality after adjusting for confounders. A U-shaped relationship was observed between the 30-day, 90-day, 180-day, and 1-year mortality and MHR, and the mortality was lowest when the MHR was 69 bpm. Kaplan-Meier curve analysis also indicated that low MHR had poor prognosis in patients undergoing cardiac surgery. According to subgroup analyses, the effect of low MHR on post-cardiac surgery survival was restricted to patients who were < 75 years old, male, without hypertension and diabetes, and of White ethnicity. MHR (69 bpm) was associated with better 30-day, 90-day, 180-day, and 1-year survival in patients after cardiac surgery. Therefore, effective HR control strategies are required in this high-risk population.

A higher resting heart rate is associated with cardiovascular event risk in patients with type 2 diabetes mellitus without known cardiovascular disease

A higher resting heart rate (RHR) is associated with an increased risk of cardiovascular events in patients with type 2 diabetes mellitus (T2DM) and cardiovascular diseases. The aim of this study was to investigate the association between RHR and cardiovascular events in T2DM patients with diabetic retinopathy and without known cardiovascular disease. We analyzed the association between RHR and cardiovascular events, including coronary, cerebral, renal and vascular events or cardiovascular death in T2DM patients with retinopathy and hyperlipidemia without prior cardiovascular events who were enrolled in the EMPATHY study. Data from 4746 patients were analyzed. The median RHR was 76 bpm. Patients were divided into four groups based on their baseline RHR ( < 60, 60-69, 70-79, and ≥80 bpm). Patients with a higher RHR were more likely to be younger and had a higher body mass index, blood pressure value, HbA1c value, and estimated glomerular filtration rate and a lower B-type natriuretic peptide value; they also had a higher proportion of current smoking status, neuropathy, and nephropathy. After adjusting for confounders, including the aforementioned risk factors, a RHR of 70-79 bpm and a RHR ≥ 80 bpm were significantly associated with cardiovascular events (hazard ratio 1.50, 95% CI 1.03-2.20; and hazard ratio 1.62, 95% CI 1.11-2.36; respectively) compared to a RHR of 60-69 bpm. The analysis using restricted cubic splines indicated that the cardiovascular risk seemed to be similarly high when the RHR range was ≥70 bpm. In conclusion, in T2DM patients with diabetic retinopathy and without known cardiovascular disease, a high RHR, particularly ≥70 bpm, was associated with the risk of cardiovascular events compared to a RHR of 60-69 bpm. High resting heart rate (RHR), particularly ≥70 bpm, was associated with the risk of cardiovascular events compared to RHR 60-69 bpm in patients with type 2 diabetes mellitus (T2DM), diabetic retinopathy, and hyperlipidemia, but without known cardiovascular disease.

Parasympathetic tonus in type 2 diabetes and pre-diabetes and its clinical implications

Autonomic imbalance reflected by higher resting heart rate and reduced parasympathetic tone may be driven by low-grade inflammation (LGI) and impaired glycemic control in type 2 diabetes mellitus (T2DM) and pre-diabetes. We examined the interaction of parasympathetic components of heart rate variability (HRV), variables of LGI, and glucose metabolism in people with T2DM, pre-diabetes, and normal glucose metabolism (NGM). We recorded HRV by Holter (48 h) in 633 community-dwelling people of whom T2DM n = 131, pre-diabetes n = 372, and NGM n = 130 and mean HbA1c of 7.2, 6.0 and 5.3%, respectively. Age was 55-75 years and all were without known cardiovascular disease except from hypertension. Fasting plasma glucose, fasting insulin, HOMA-IR, HbA1c and LGI (CRP, Interleukin-18 (IL-18), and white blood cells) were measured. Root-mean-square-of-normal-to-normal-beats (RMSSD), and proportion of normal-to-normal complexes differing by more than 50 ms (pNN50) are accepted measures of parasympathetic activity. In univariate analyses, RMSSD and pNN50 were significantly inversely correlated with level of HbA1c and CRP among people with T2DM and pre-diabetes, but not among NGM. RMSSD and pNN50 remained significantly inversely associated with level of HbA1c after adjusting for age, sex, smoking, and BMI among people with T2DM (β = - 0.22) and pre-diabetes (β = - 0.11); adjustment for LGI, HOMA-IR, and FPG did not attenuate these associations. In backward elimination models, age and level of HbA1c remained associated with RMSSD and pNN50. In people with well controlled diabetes and pre-diabetes, a lower parasympathetic activity was more related to age and HbA1c than to markers of LGI. Thus, this study shows that the driver of parasympathetic tonus may be more the level of glycemic control than inflammation in people with prediabetes and well controlled diabetes.

Regular physical activity: a major component of isolated systolic hypertension in the young

In the last few decades there has been much debate about the clinical significance of isolated systolic hypertension in youth (ISHY). Purpose of this article is to discuss the epidemiology and pathophysiology of ISHY focusing on the relationship between ISHY and aerobic exercise. There is evidence to suggest that regular physical activity produces favourable long-standing cardiovascular effects in young individuals including the improvement of arterial elasticity as measured from carotid-femoral pulse wave velocity and from small artery compliance. A recent ESH document recognises the heterogeneity of ISHY which may be associated with multiple factors that can interact to determine this BP phenotype. Several studies have shown that long-term training in aerobic sports is one main factor contributing to ISHY. In the athlete, the increased stroke volume secondary to low heart rate and the high arterial elasticity causes an increase in peripheral pulse pressure. This explains why ISHY is more common in physically trained than in sedentary individuals and is considered by some authors as a spurious hypertension. Recent results from the HARVEST study confirm the existence of an association between ISHY and endurance training. In that study the prevalence of ISHY was directly related to physical activity habits being 8.8% in the sedentary subjects and 25.7% in the athletes. Eligibility to competitive athletics of athletes with ISHY should be based on the results of 24-hour ambulatory BP monitoring and careful clinical assessment of all cardiovascular risk factors and target organ involvement in order to establish the global level of risk.

The Nadir Oxygen-Specific Heart Rate Response in Sleep Apnea Links With the Occurrence of Acute Myocardial Infarction

Background

Little is known regarding the quantification of sleep apnea- and hypoxemia-elicited heart rate (HR) response and its prognostic significance of the cardiovascular risk. We sought to explore the impact of HR response and variability specific to obstructive sleep apnea (OSA) on the occurrence of a common cardiovascular event – acute myocardial infarction (AMI).

Methods

Consecutive patients with suspected OSA were enrolled and underwent nocturnal respiratory study and electrocardiography monitoring. The minimal oxygen saturation (minSpO2) was determined from the oxygen saturation curve under a subject-specific search window. Primary HR metrics such as maximal HR in response to minSpO2 and respiratory event-specific HR variability were computed from the synchronized recordings. Multivariate regression analyses were conducted to analyze the associations between individualized HR metrics and the occurrence of AMI.

Results

Of 2,748 patients recruited, 39% (n = 1,071) had moderate-to-severe OSA (respiratory event index, REI ≥ 15), and 11.4% (n = 313) patients had AMI. Patients with AMI experienced severe OSA, severe minSpO2, and greater HR reactions. Patients with minSpO2 &lt;90% had an adjusted odds ratio (OR) of 1.48 [95% confidence interval (CI): 1.09–2.00, p = 0.012) for AMI. Notably, minSpO2-induced elevated mean HR response (HRmean &gt; 73 bpm) was significantly associated with AMI (OR 1.72, 95% CI: 1.32–2.23, p &lt; 0.001). Patients with both severe minSpO2 (&lt;90%) and elevated HRmean carried an additive OR of 2.65 (95% CI: 1.74–4.05, p &lt; 0.001) for the risk of AMI after adjustment for potential confounders. A large total power spectrum specific to respiratory events was correlated with an adjusted OR of 0.61 for AMI risk.

Conclusion

Patients with substantial HR reactions to OSA-induced oxygen nadir and restricted cardiac cycle shifting to respiratory events were likely at increased risk of developing AMI. Detection of nocturnal HR response to hypoxemia may help improve cardiovascular risk stratification.

Ivabradine in the management of COVID-19-related cardiovascular complications: A perspective

Abstract:

Besides acute respiratory distress syndrome, acute cardiac injury is a major complication in severe coronavirus disease 2019 (COVID-19) and associates with a poor clinical outcome. Acute cardiac injury with COVID-19 can be of various etiologies, including myocardial ischemia or infarction and myocarditis, and may compromise cardiac function, resulting in acute heart failure or cardiogenic shock. Systemic inflammatory response increases heart rate (HR), which disrupts the myocardial oxygen supply/demand balance and worsens cardiac energy efficiency, thus further deteriorating the cardiac performance of the injured myocardium. In fact, the combination of elevated resting HR and markers of inflammation synergistically predicts adverse cardiovascular prognosis. Thus, targeted HR reduction may potentially be of benefit in cardiovascular pathologies associated with COVID-19. Ivabradine is a drug that selectively reduces HR via If current inhibition in the sinoatrial node without a negative effect on inotropy. Besides selective HR reduction, ivabradine was found to exert various beneficial pleiotropic effects, either HR-dependent or HR-independent, including anti-inflammatory, anti-atherosclerotic, anti-oxidant and antiproliferative actions and the attenuation of endothelial dysfunction and neurohumoral activation. Cardioprotection by ivabradine has already been indicated in cardiovascular pathologies that are prevalent with COVID-19, including myocarditis, acute coronary syndrome, cardiogenic shock or cardiac dysautonomia. Here, we suggest that ivabradine may be beneficial in the management of COVID-19-related cardiovascular complications.

Effect of Presence versus Absence of Hypertension on Admission Heart Rate-Associated Cardiovascular Risk in Patients with Acute Coronary Syndrome

Background and Aims

Heart rate (HR) and hypertension are both important risk factors for adverse cardiovascular (CV) events in patients with established coronary artery disease (CAD). We sought to evaluate whether hypertension can modify the effect of admission HR on adverse CV events in patients with acute coronary syndrome (ACS).

Methods

A total of 1056 patients with ACS undergoing percutaneous coronary intervention (PCI) were analyzed. All patients were classified into three groups according to the tertiles of admission HR (T1: ≤66 bpm, n = 369; T2: 67–73 bpm, n = 322; and T3: ≥74 bpm, n = 365). The primary endpoint was defined as major adverse CV events (MACEs), including all-cause death, stroke, myocardial infarction, or unplanned repeat revascularization. The multivariate Cox regression model was performed to evaluate the association of admission HR with MACE stratified by hypertension.

Results

During the median follow-up of 30 months, a total of 232 patients developed at least one event. After adjusting for other covariates, elevated admission HR was significantly associated with an increased risk of MACE only in patients with hypertension (when T1 was taken as a reference, the adjusted HR of T2 was 1.143 [95% CI: 0.700–1.864] and that of T3 was 2.062 [95% CI: 1.300–3.270]); however, in patients without hypertension, admission HR was not associated with the risk of MACE (when T1 was taken as a reference, the adjusted HR of T2 was 0.744 [0.406–1.364] and that of T3 was 0.614 [0.342–1.101]) (P=0.025 for interaction).

Conclusions

In patients with ACS undergoing PCI, the association of elevated admission HR with an increased risk of MACE was present in individuals with hypertension but not in those without hypertension. This finding suggests a potential benefit of HR control for ACS patients when they concomitantly have hypertension.

Effects of high-intensity interval training on improving arterial stiffness in Chinese female university students with normal weight obese: a pilot randomized controlled trial

Background

High intensity interval training (HIIT) has been reported to exert better effects on cardiovascular fitness in obesity, but little known about the arterial stiffness (AS) in female university students with normal weight obesity (NWO). Thus, this study aimed to investigate the effects of HIIT on the body composition, heart rate (HR), blood pressure (BP), blood lipids metabolism as well as the novel parameters of propensity for AS (arterial velocity pulse index [AVI], arterial pressure volume index [API]) for female university students with NWO.

Methods

Forty female university students with NWO were randomly assigned to control group (n = 20) and HIIT group (3 bouts of 9‑min intervals at 90% of the maximal heart rate [HR_max], interspersed by 1 min rest, 5 days a week, n = 20). Tests were performed before and after 4 weeks of training. Repeated measures ANOVA and simple effect test analysis were used to analyze dependent variable changes.

Results

After 4 weeks HIIT statistically significantly improved the body composition by decreasing the body mass index, body fat percent, total body fat mass (BFM), BFM of left arm, measured circumference of left arm, and obesity degree, and increasing the total body skeletal muscle mass, protein content, total body water, fat free mass, body cell mas, and InBody score. HIIT also statistically significantly decreased the HR and BP. As for the lipid profile, HIIT obviously ameliorated the blood lipids metabolism by decreasing the levels of total cholesterol (TC), triglyceride, low-density lipoprotein, and TC/HDL, and increasing the levels of high-density lipoprotein (HDL). In addition, the AVI and API were markedly decreased via HIIT intervention.

Conclusions

HIIT produced significant and meaningful benefits for body composition, HR, BP, and blood lipids metabolism, and could decrease AS in female university students with NWO. This suggests that HIIT may effectively reduce the risk of arteriosclerosis and protect the cardiovascular function for female university students with NWO.

Trial registration ChiCTR2100050711. Registered 3 September 2021. Retrospectively registered.

Mechanism of cell death of endothelial cells regulated by mechanical forces

Cell death of endothelial cells (ECs) is a common devastating consequence of various vascular-related diseases. Atherosclerosis, hypertension, sepsis, diabetes, cerebral ischemia and cardiac ischemia/reperfusion injury, and chronic kidney disease remain major causes of morbidity and mortality worldwide, in which ECs are constantly subjected to a great amount of dynamic changed mechanical forces including shear stress, extracellular matrix stiffness, mechanical stretch and microgravity. A thorough understanding of the regulatory mechanisms by which the mechanical forces controlled the cell deaths including apoptosis, autophagy, and pyroptosis is crucial for the development of new therapeutic strategies. In the present review, experimental and clinical data highlight that nutrient depletion, oxidative stress, tumor necrosis factor-α, high glucose, lipopolysaccharide, and homocysteine possess cytotoxic effects in many tissues and induce apoptosis of ECs, and that sphingosine-1-phosphate protects ECs. Nevertheless, EC apoptosis in the context of those artificial microenvironments could be enhanced, reduced or even reversed along with the alteration of patterns of shear stress. An appropriate level of autophagy diminishes EC apoptosis to some extent, in addition to supporting cell survival upon microenvironment challenges. The intervention of pyroptosis showed a profound effect on atherosclerosis. Further cell and animal studies are required to ascertain whether the alterations in the levels of cell deaths and their associated regulatory mechanisms happen at local lesion sites with considerable mechanical force changes, for preventing senescence and cell deaths in the vascular-related diseases.

The effect of grape (Vitis vinifera) seed extract supplementation on flow-mediated dilation, blood pressure, and heart rate: A systematic review and meta-analysis of controlled trials with duration- and dose-response analysis

The objective of this systematic review and meta-analysis of controlled trials was to assess the long-term effect of grape seed extract (GSE) supplementation on flow-mediated dilation (FMD), systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) in adults. Web of Science, Scopus, Medline, Cochrane Library, and Google Scholar were searched up to May 24, 2021. Nineteen trials were included in this study. Weighted mean difference (WMD) and 95% confidence interval (CI) were calculated using a random-effects model. GSE supplementation significantly reduced DBP (WMD: -2.20 mmHg, 95% CI: -3.79 to -0.60, I² = 88.8%) and HR (WMD: -1.25 bpm, 95% CI: -2.32 to -0.19, I² = 59.5%) but had no significant effects on FMD (WMD: 1.02%, 95% CI: -0.62 to 2.66, I² = 92.0%) and SBP (WMD: -3.55 mmHg, 95% CI: -7.59 to 0.49, I² = 97.4%). Subgroup analysis revealed that the dose and duration of GSE administration and the characteristics of study participants could be sources of between-study heterogeneity. Significant non-linear relationships were found between DBP and the duration of GSE supplementation (P = 0.044) and its dose (P = 0.007). In conclusion, GSE may be beneficial for individuals with or at risk of cardiovascular disease because it may have hypotensive and HR-lowering properties.

Remodelling is inversely proportional to left ventricular dimensions in a real-life population of patients with chronic heart failure after therapy with sacubitril/valsartan

BACKGROUND

Left ventricular (LV) remodelling is a major mechanism underlying disease progression in patients with heart failure (HF) with reduced ejection fraction (EF). Previous studies that LVEF improvement and reverse remodelling can be achieved after therapy with Sacubitril/Valsartan in real-world settings. Therefore, we sought to investigate possible predictors of LV remodelling, in particular echocardiographic parameters derived by Tissue Doppler Imaging.

METHODS

Patients with chronic HF, LV dysfunction (EF < 35%), NYHA class II-III were followed up between September 2016 and January 2019. All patients underwent clinical and echocardiography follow up at baseline and after 12 months of therapy with sacubitril/valsartan.

RESULTS

Fifty-four consecutive outpatients were enrolled in the study. At follow-up visit LVEF (38 ± 9 vs. 30 ± 5%, p < 0.0001), LVEDD (61 ± 8 vs. 62 ± 8 mm, p = 0.0085), LVESV (114 ± 57 vs. 130 ± 56 mm³, p = 0.0001), mitral regurgitation severity (1 ± 1 vs. 2 ± 1, p < 0.0001), and left atrial area (23 ± 6 vs. 24 ± 6 mm², p = 0.0121) changed compared to the baseline value. Changes in LVEF (follow up vs baseline) correlated with baseline levels of heart rate (r = 0.24, p = 0.048), LVEDD (r= -0.33, p = 0.004), LVEDV (r= -0.39, p = 0.001), LVESV (r = 0.37, p = 0.002), and changes in LVESV (r=-0.34, p = 0.006). Correlations remained significant even after correction at multivariate analysis including age and gender.

CONCLUSIONS

Treatment with sacubitril/valsartan in patients with systolic dysfunction is associated with an improvement in LVEF in a real world scenario. Smaller LV volumes are associated with better reverse LV remodelling.

Prognostic impact of resting heart rate in patients with peripheral artery disease

OBJECTIVES

Resting heart rate has been increasingly identified as a marker of cardiovascular risk and has been extensively studied as a predictor of coronary artery disease progression. In peripheral artery disease, the prognostic impact of resting heart rate remains elusive.

METHODS

Consecutive patients undergoing invasive peripheral procedures were included. Data included resting heart rate determination by averaging manual radial pulse palpation measurements taken 24 h before and after an invasive peripheral procedure.

RESULTS

A total of 1720 patients were included (mean age 70±11 years, 38% were female, 39% had critical limb ischemia). During a median follow-up of 729 days, 364 (21.2%) patients died. Resting heart rate emerged as an independent predictor of mortality, even after adjusting for clinical characteristics, peripheral artery disease manifestation and anatomic extent, traditional risk factors, co-morbidities, and disease-modifying therapies: hazard ratio for heart rate >75 bpm was 1.010 (95% confidence interval 1.001-1.109), with each bpm increase in resting heart rate conferring a 1.1% increase in the risk of all-cause mortality (95% confidence interval 0.1-10.9%, adjusted p = 0.030).

CONCLUSIONS

Resting heart rate is an independent predictor of mortality in patients with peripheral artery disease; our findings extend heart rate as a possible marker of prognosis to non-coronary atherosclerotic vascular disease.

The relationship between resting heart rate and new-onset microalbuminuria in people with type 2 diabetes: An 8-year follow-up study

AIMS

Microalbuminuria is an indicator of adverse cardiovascular events and chronic kidney disease. Studies have described an elevated resting heart rate as a risk factor for microalbuminuria in people with cardiovascular disease, but none have clarified its role in microalbuminuria development in people with type 2 diabetes. Therefore, this study investigated the relationship between resting heart rate and new-onset microalbuminuria in type 2 diabetes.

METHODS

A total of 788 people from a glycaemic control trial in Taiwan were enrolled. Microalbuminuria was defined as a fasting urine albumin-to-creatinine ratio ≥30 mg/g in two consecutive urine tests. Resting heart rate and other covariates were measured at baseline. The quartile of resting heart rates, categorized as <70, 70-74, 75-80 and >80 beats/min, was used for analysis. Cox proportional hazard models were used to evaluate the association between resting heart rate and risk of microalbuminuria.

RESULTS

During the follow-up period, 244 people (31%) developed microalbuminuria. Those who developed microalbuminuria had a longer diabetes duration (median = 3.0 vs. 2.0 years, p < 0.001), higher rate of hypertension (77% vs. 66%, p = 0.003), higher rate of angiotensin-converting enzyme inhibitor/angiotensin receptor blocker treatment (50% vs. 38%, p = 0.001) and higher baseline HbA_1c level (70 vs. 64 mmol/mol, 8.6 vs. 8.0%, p < 0.001). After adjusting for demographics, metabolic profiles and inflammatory markers, developing microalbuminuria was significantly associated with baseline resting heart rate of 70-74, 75-80 and >80 beats/min (with hazard ratios [95% CI] of 2.05 [1.32, 3.18], 2.10 [1.32, 3.32] and 1.62 [1.01, 2.59], respectively) compared to resting heart rates <70 beats/min. An average increased risk of microalbuminuria for increment of 10 beats/min was about 24% among those with hypertension (with hazard ratios of 1.24 [1.05, 1.47] in the multivariable Cox model).

CONCLUSIONS

This prospective cohort study showed that resting heart rate may be an associative risk factor for developing microalbuminuria in type 2 diabetes.

Resting Heart Rate as a Cardiovascular Risk Factor in Hypertensive Patients: An Update

A large body of evidence has shown that resting heart rate (RHR) holds important prognostic information in several clinical conditions. In the majority of the general population studies, a graded association between RHR and mortality from all causes, cardiovascular (CV) disease, ischemic heart disease, and stroke has been observed. These associations appeared even stronger and more consistent in hypertensive patients. Studies performed with 24-hour ambulatory recording have shown that an elevated nighttime heart rate may confer an additional risk on top of office RHR. The mechanisms by which tachycardia alone or in association with sympathetic overactivity induces CV damage are well understood. Fast RHR is a strong predictor of future hypertension, metabolic disturbances, obesity, and diabetes. Several experimental lines of research point to high RHR as a main risk factor for the development of atherosclerosis, large artery stiffness, and CV disease. Elevated RHR is a common feature in patients with hypertension. Thus, there is a large segment of the hypertensive population that would benefit from a treatment able to decrease RHR. Improvement of unhealthy lifestyle should be the first goal in the management of the hypertensive patient with elevated RHR. Most clinical guidelines now recommend the use of combination therapies even in the initial treatment of hypertension. Although no results of clinical trials specifically designed to investigate the effect of RHR lowering in human beings without CV diseases are available, in hypertensive patients with high RHR a combination therapy including a cardiac slowing drug at optimized dose seems a sensible strategy. Tachycardia can be considered both as a marker of sympathetic overactivity and as a risk factor for cardiovascular events. In this sketch, the main cardiovascular and metabolic effects of increased sympathetic tone underlying high heart rate are shown. The link between tachycardia and cardiovascular events can be explained also by the direct hemodynamic action of heart rate on the arteries and the left ventricular (LV) wall.

Minimum heart rate and mortality in critically ill myocardial infarction patients: an analysis of the MIMIC-III database

Background

Low minimum heart rate (MHR) is common in critically ill myocardial infarction (MI) patients. However, the association between MHR and the mortality of critically ill MI patients remains unclear.

Methods

In this retrospective cohort study, a total of 2,031 critically ill MI patients were enrolled from the Medical Information Mart for Intensive Care (MIMIC)-III database. Patients were divided into a low MHR group [MHR <60 beats per minute (bpm)] and a high MHR group (MHR ≥60 bpm). A Cox proportional hazard model was used to elucidate the association between these two groups and the mortality of MI patients. The association between mortality and MHR as a continuous variable was analyzed non-parametrically using restricted cubic splines. Sensitivity analyses were conducted to determine the impact of different admission heart rate, hypertension, atrial fibrillation, and vasopressor use on our results.

Results

MI patients in the low MHR group had higher 30-day and 1-year mortality than those in the high MHR group (20.59% vs. 10.91%, P<0.001 and 29.76% vs. 19.31%, P<0.001, respectively). After adjustment, the low MHR group was significantly correlated with 30-day mortality [hazard ratio, 1.779, 95% confidence interval (CI), 1.400-2.261, P<0.001] and 1-year mortality (hazard ratio, 1.537, 95% CI, 1.272-1.859, P<0.001). This correlation remained remarkable in patients with low or high admission heart rate, with or without hypertension, and with or without atrial fibrillation. An apparent L-curve relationship was observed between the 30-day mortality or 1-year mortality and MHR as a continuous variable.

Conclusions

MHR under 60 bpm may be associated with a higher risk for both 30-day and 1-year mortality in critically ill MI patients. These findings highlight the possibility of MHR as an early risk indicator and potential therapeutic target for mortality in critically ill MI patients, which warrants further investigation.

High heart rate amplifies the risk of cardiovascular mortality associated with elevated uric acid

AIMS

Whether the association between uric acid (UA) and cardiovascular disease is influenced by some facilitating factors is unclear. The aim of this study was to investigate whether the risk of cardiovascular mortality (CVM) associated with elevated UA was modulated by the level of resting heart rate (HR).

METHODS AND RESULTS

Multivariable Cox analyses were made in 19 128 participants from the multicentre Uric acid Right for heArt Health study. During a median follow-up of 11.2 years, there were 1381 cases of CVM. In multivariable Cox models both UA and HR, either considered as continuous or categorical variables were independent predictors of CVM both improving risk discrimination (P ≤ 0.003) and reclassification (P < 0.0001) over a multivariable model. However, the risk of CVM related to high UA (≥5.5 mg/dL, top tertile) was much lower in the subjects with HR

CONCLUSION

This data suggest that the contribution of UA to determining CVM is modulated by the level of HR supporting the hypothesis that activation of the sympathetic nervous system facilitates the action of UA as a cardiovascular risk factor.

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Key Words

• Cardiovascular
• Heart rate
• Longitudinal study
• Mortality
• Sympathetic activity
• Uric acid

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Affiliation(s)

Paolo Palatini Department of Medicine, Studium Patavinum, University of Padova, Via S. Fris 121, 31029 Vittorio Veneto, Italy
Gianfranco Parati S. Luca Hospital, Istituto Auxologico Italiano & University of Milan-Bicocca, Milan, Italy
Agostino Virdis Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
Gianpaolo Reboldi Department of Medical and Surgical Science, University of Perugia, Perugia, Italy
Stefano Masi Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
Alessandro Mengozzi Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
Edoardo Casiglia Department of Medicine, University of Padua, Padua, Italy
Valerie Tikhonoff Department of Medicine, University of Padua, Padua, Italy
Arrigo F G Cicero Alma Mater Studiorum University of Bologna, Bologna, Italy
Andrea Ungar Department of Geriatric and Intensive Care Medicine, Careggi Hospital and University of Florence, Florence, Italy
Giulia Rivasi Department of Geriatric and Intensive Care Medicine, Careggi Hospital and University of Florence, Florence, Italy
Massimo Salvetti Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
Carlo M Barbagallo Biomedical Department of Internal Medicine and Specialistics, University of Palermo, Palermo, Italy
Michele Bombelli Department of Cardiovascular, Neural and Metabolic Sciences, Clinica Medica, Monza, Italy Department of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
Raffaella Dell'Oro Department of Cardiovascular, Neural and Metabolic Sciences, Clinica Medica, Monza, Italy Department of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
Berardino Bruno Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy
Luciano Lippa Italian Society of General, Medicine (SIMG), Avezzano, L'Aquila, Italy
Lanfranco D'Elia Department of Clinical Medicine and Surgery, "Federico II" University of Naples Medical School, Naples, Italy
Paolo Verdecchia Hospital S. Maria della Misericordia, Perugia, Italy
Fabio Angeli Department of Medicine and Surgery, University of Insubria, Varese, Italy Department of Medicine and Cardiopulmonary Rehabilitation, Maugeri Care and Research Institutes, IRCCS Tradate, Varese, Italy
Francesca Mallamaci CNR-IFC, Clinical Epidemiology of Renal Diseases and Hypertension, Reggio Cal Unit, Reggio Calabria, Italy
Massimo Cirillo Department of Public Health, "Federico II" University of Naples, Napoli, Italy
Marcello Rattazzi Department of Medicine-DIMED, University of Padova, Medicina, Interna 1°, Ca' Foncello University Hospital, Treviso, Italy
Pietro Cirillo Department of Emergency and Organ Transplantation-Nephrology, Dialysis and Transplantation Unit, Aldo Moro University of Bari, Bari, Italy
Loreto Gesualdo Department of Emergency and Organ Transplantation-Nephrology, Dialysis and Transplantation Unit, Aldo Moro University of Bari, Bari, Italy
Alberto Mazza Department of Internal Medicine, Hypertension Unit, General Hospital, Rovigo, Italy
Cristina Giannattasio Cardiology IV, 'A. De Gasperis' Department, Niguarda Ca' Granda Hospital, Milano, Italy Health Science Department, Milano-Bicocca University, Milano, Italy
Alessandro Maloberti Cardiology IV, 'A. De Gasperis' Department, Niguarda Ca' Granda Hospital, Milano, Italy Health Science Department, Milano-Bicocca University, Milano, Italy
Massimo Volpe Hypertension Unit, Division of Cardiology, Department of Clinical and Molecular Medicine, Faculty of Medicine and Psychology, University of Rome Sapienza, Sant'Andrea Hospital, Rome, Italy IRCCS Neuromed, Pozzilli (IS), Italy
Giuliano Tocci Hypertension Unit, Division of Cardiology, Department of Clinical and Molecular Medicine, Faculty of Medicine and Psychology, University of Rome Sapienza, Sant'Andrea Hospital, Rome, Italy IRCCS Neuromed, Pozzilli (IS), Italy
Georgios Georgiopoulos First Department of Cardiology, 'Hippokration' Hospital, University of Athens, Medical School, Athens, Greece
Guido Iaccarino Department of Advanced Biomedical Sciences, "Federico II" University of Naples, Napoli, Italy
Pietro Nazzaro Department of Medical Basic Sciences, Neurosciences and Sense Organs, University of Bari Medical School, Bari, Italy
Ferruccio Galletti Department of Clinical Medicine and Surgery, "Federico II" University of Naples Medical School, Naples, Italy
Claudio Ferri Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy
Giovambattista Desideri Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy
Francesca Viazzi Department of Internal Medicine, University of Genoa and Policlinico San Martino, Genova, Italy
Roberto Pontremoli Department of Internal Medicine, University of Genoa and Policlinico San Martino, Genova, Italy
Maria Lorenza Muiesan Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
Guido Grassi Department of Cardiovascular, Neural and Metabolic Sciences, Clinica Medica, Monza, Italy Department of Medicine and Surgery, University of Milano-Bicocca, Monza, Italy
Claudio Borghi Alma Mater Studiorum University of Bologna, Bologna, Italy

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Prognostic impact of mean heart rate by Holter monitoring on long-term outcome in patients with ST-segment elevation myocardial infarction undergoing percutaneous coronary intervention

BACKGROUND

Previous studies have shown elevated admission heart rate (HR) was associated with worse outcome in patients with myocardial infarction (MI). However, the prognostic value of mean heart rate (MHR) with Holter monitoring remains unclear.

OBJECTIVES

Our present study aims to evaluate the impact of MHR by Holter monitoring on long-term mortality in patients with ST-segment elevation myocardial infarction (STEMI).

METHODS

1013 STEMI patients were divided into four groups according to the quartiles of MHR by Holter monitoring, Q1 (< 66 bpm), Q2 66-72 bpm), Q3 (73-78 bpm), and Q4 (> 78 bpm). The endpoint was long-term all-cause mortality. The predictive value of admission HR, discharge HR, and MHR was compared with receiver operating characteristic (ROC) curves.

RESULTS

Patients in Q4 were more likely to present with anterior MI, high Killip class, relatively lower admission blood pressure, significantly increased troponin I, B-type natriuretic peptide, and decreased left ventricular ejection fraction. During a median of 28.3 months follow up period, 91 patients (8.9%) died. The mortality in Q4 was significantly higher than in the other three groups (P < 0.001). After multivariate adjustment, Q4 was associated with a 1.0-fold increased risk of long-term all-cause mortality (HR = 2.096, 95% CI 1.190-3.691, P = 0.010). ROC analysis shows MHR with Holter (AUC = 0.672) was superior to admission HR (AUC = 0.556) or discharge HR (AUC = 0.578).

CONCLUSIONS

MHR based on Holter monitoring provided important prognostic value and MHR > 78 bpm was independently associated with increased risk of long-term all-cause mortality in patients with STEMI, and its predictive validity was superior to admission or discharge HR.

Heart rate at discharge in patients with acute decompensated heart failure is a predictor of mortality

Aims

Heart failure is a syndrome with increasing prevalence in concordance with the aging population and better survival rates from myocardial infarction. Morbidity and mortality are high in chronic heart failure patients, particularly in those with hospital admission for acute decompensation. Several risk stratification tools and score systems have been established to predict mortality in chronic heart failure patients. However, identification of patients at risk with easy obtainable clinical factors that can predict mortality in acute decompensated heart failure (ADHF) are needed to optimize the care-path.

Methods and results

We retrospectively analyzed electronic medical records of 78 patients with HFrEF and HFmrEF who were hospitalized with ADHF in the Heart Center of the University Hospital Cologne in the year 2011 and discharged from the ward after successful treatment. 37.6 ± 16.4 months after index hospitalization 30 (38.5%) patients had died. This mortality rate correlated well with the calculated predicted survival with the Seattle Heart Failure Model (SHFM) for each individual patient. In our cohort, we identified elevated heart rate at discharge as an independent predictor for mortality (p = 0.016). The mean heart rate at discharge was lower in survived patients compared to patients who died (72.5 ± 11.9 vs. 79.1 ± 11.2 bpm. Heart rate of 77 bpm or higher was associated with an almost doubled mortality risk (p = 0.015). Heart rate elevation of 5 bpm was associated with an increase of mortality of 25% (p = 0.022).

Conclusions

Patients hospitalized for ADHF seem to have a better prognosis, when heart rate at discharge is < 77 bpm. Heart rate at discharge is an easily obtainable biomarker for risk prediction of mortality in HFrEF and HFmrEF patients treated for acute cardiac decompensation. Taking into account this parameter could be useful for guiding treatment strategies in these high-risk patients. Prospective data for validation of this biomarker and specific intervention are needed.

Effects of heart rate reduction with ivabradine on vascular stiffness and endothelial function in chronic stable coronary artery disease

INTRODUCTION

Epidemiological and clinical studies have shown a relevant association between heart rate and cardiovascular mortality. Experimental studies identified vascular effects of heart rate reduction with the If channel inhibitor ivabradine. Therefore, the effects of heart rate reduction on endothelial function and indices of arterial stiffness were examined in patients with stable coronary artery disease in a prospective, placebo-controlled clinical crossover study.

METHODS AND RESULTS

Twenty-three patients (18 men and 5 women) with a resting heart rate (HR) of at least 70 beats per minute (bpm) and stable coronary artery disease were enrolled in this study. In a cross-over design, all patients were treated with ivabradine (Iva, 7.5 mg b.i.d.) and placebo for 6 months each. Iva reduced heart rate by 11.4 bpm (Iva 58.8 ± 8.2 bpm vs. placebo 70.2 ± 8.3 bpm, P < 0.0001). Augmentation index (AIx75), carotid-femoral pulse wave velocity (cfPWV) and central aortic blood pressure were measured using applanation tonometry (SphygmoCor). HRR by Iva increased AIx75 by 12.4% (Iva 24.3 ± 10.5% vs. placebo 21.3 ± 10.1%, P < 0.05) and reduced cfPWV by 14.1% (Iva 6.3 ± 1.7 m/s vs. placebo 7.3 ± 1.4 m/s, P < 0.01). Iva increased mean central blood pressure by 7.8% (Iva 107.5 ± 15.4 mmHg vs. placebo 99.1 ± 12.2 mmHg, P < 0.001). Endothelial function was determined measuring the flow-mediated vasodilation (FMD) of the brachial artery. HRR by Iva increased FMD by 18.5% (Iva 7.3 ± 2.2% vs. placebo 6.0 ± 2.0%, P < 0.001). Aortic distensibility was characterized by MRI. HRR by Iva increased aortic distensibility by 33.3% (Iva 0.003 ± 0.001/mmHg vs. placebo 0.002 ± 0.010/mmHg, P < 0.01) and circumferential cyclic strain by 37.1% (Iva 0.062 ± 0.027 vs. placebo 0.039 ± 0.018, P < 0.0001).

CONCLUSION

Heart rate reduction with Iva increased endothelium-dependent vasodilation and reduced arterial stiffness in patients with stable CAD. These findings corroborate and expand the results collected in experimental studies and indicate the importance of heart rate as a determinant of vascular function.

Elevated resting heart rate in adolescent men and risk of heart failure and cardiomyopathy

Aims

This study aims to investigate the association of resting heart rate (RHR) measured in late adolescence with long‐term risk of cause‐specific heart failure (HF) and subtypes of cardiomyopathy (CM), with special attention to cardiorespiratory fitness.

Methods and results

We performed a nation‐wide, register‐based cohort study of all Swedish men enrolled for conscription in 1968–2005 (n = 1 008 363; mean age = 18.3 years). RHR and arterial blood pressure were measured together with anthropometrics as part of the enlistment protocol. HF and its concomitant diagnoses, as well as all CM diagnoses, were collected from the national inpatient, outpatient, and cause of death registries. Risk estimates were calculated by Cox‐proportional hazards models while adjusting for potential confounders. During follow‐up, there were 8400 cases of first hospitalization for HF and 3377 for CM. Comparing the first and fifth quintiles of the RHR distribution, the hazard ratio (HR) for HF associated with coronary heart disease, diabetes, or hypertension was 1.25 [95% confidence interval (CI) = 1.13–1.38] after adjustment for body mass index, blood pressure, and cardiorespiratory fitness. The corresponding HR was 1.43 (CI = 1.08–1.90) for HF associated with CM and 1.34 (CI = 1.16–1.54) for HF without concomitant diagnosis. There was an association between RHR and dilated CM [HR = 1.47 (CI = 1.27–1.71)] but not hypertrophic, alcohol/drug‐induced, or other cardiomyopathies.

Conclusions

Adolescent RHR is associated with future risk of HF, regardless of associated aetiological condition. The association was strongest for HF associated with CM, driven by the association with dilated CM. These findings indicate a causal pathway between elevated RHR and myocardial dysfunction that warrants further investigation.

Electroacupuncture Ameliorates Acute Myocardial Ischemia: A Potential Role of the Locus Coeruleus

The locus coeruleus (LC) is closely linked with cardiovascular disease. However, whether it mediates the alleviating effect of electroacupuncture (EA) on acute myocardial ischemia (AMI) remains unclear. A rat model of myocardial ischemia was established through occlusion of the left anterior descending coronary artery. Multichannel in vivo recording and other techniques were used to assess neurons in the LC, norepinephrine (NE) and dopamine (DA) levels in central and myocardial tissue, serum levels of inflammatory factors, and cardiac function. After induction of AMI, LC neuron activity increased and the central NE concentrations increased, while those of DA decreased. Moreover, the serum levels of high-sensitivity C-reactive protein (hs-CRP) increased, whereas those of interleukin-10 (IL-10) decreased. However, these effects were reversed by EA. Additionally, LC lesioning affected NE and DA levels in myocardial tissue and weakened the antimyocardial ischemic effect of EA. Collectively, our results indicated that LC is closely related to AMI and plays an important role in the antimyocardial ischemic effect of EA. This mechanism may be related to inhibition of LC neuron activity by EA, which inhibits the release of large amounts of hs-CRP and promotes that of IL-10 in the serum. Besides, after LC lesioning, EA may improve cardiac function by inhibiting the release of large amounts of NE and promoting the release of DA in myocardial tissue.

Heart rate and early progression of cardiac allograft vasculopathy: A prospective study using highly automated 3-D optical coherence tomography analysis

INTRODUCTION

Heart rate slowing agents are frequently prescribed to manage heart transplant (HTx) patients with the assumption that higher heart rate is a risk factor in cardiovascular disease.

PATIENTS AND METHODS

This prospective two-center study investigated early progression of cardiac allograft vasculopathy (CAV) in 116 HTx patients. Examinations by coronary optical coherence tomography and 24-hour ambulatory ECG monitoring were performed both at baseline (1 month after HTx) and during follow-up (12 months after HTx).

RESULTS

During the first post-HTx year, we observed a significant reduction in the mean coronary luminal area from 9.0 ± 2.5 to 8.0 ± 2.4 mm² (P < .001), and progression in mean intimal thickness (IT) from 106.5 ± 40.4 to 130.1 ± 53.0 µm (P < .001). No significant relationship was observed between baseline and follow-up mean heart rates and IT progression (R = .02, P = .83; R = -.13, P = .18). We found a mild inverse association between beta-blocker dosage at 12 months and IT progression (R = -.20, P = .035).

CONCLUSION

Our study did not confirm a direct association between mean heart rate and progression of CAV. The role of beta blockers warrants further investigation, with our results indicating that they may play a protective role in early CAV development.

[The Use of Selective Inhibitor of If-Channels Ivabradine in Patients with Ischemic Heart Disease, Heart Failure with High Heart Rate]

Ischemic heart disease (IHD) and chronic heart failure (CHF) belong to leading causes of death among patients with cardiovascular diseases (CVD). Modern medical approaches to the treatment of patients with CHF do not always provide a significant improvement in the quality of life, a decrease in the frequency of CHF exacerbations and hospitalizations, and an improvement of the long-term prognosis. According to the neurohumoral theory of IHD and CHF development, the blockade of the sympathoadrenal system with β-adrenoblockers (β-AB) is pathogenetically substantiated, and preparations of this group are recommended as one of the main classes of drugs for the treatment of patients with CHF. However, selection of heart rhythm slowing therapy in patients with CHF of ischemic genesis is often difficult due to the development of undesirable side effects of β-AB, intolerance and/or due to the presence of contraindications for their use. Randomized studies have shown that prescribing a combination of β-AB and If-channel blocker ivabradine for heart rate (HR) reduction or solely ivabradine when use of β-AB is impossible in complex CHF therapy, improves the left ventricle (LV) diastolic function, reducing mortality from CHF decompensation. However, the prognostic significance of the use of ivabradine in patients with CHF with preserved left ventricular ejection fraction of ischemic genesis with heart rate higher than 70 beats/min receiving maximum tolerated doses of β-AB remains not fully investigated.

Tiaopi huxin recipe improved endothelial dysfunction and attenuated atherosclerosis by decreasing the expression of caveolin-1 in ApoE-deficient mice

The Tiaopi Huxin recipe (TPHXR) is widely used in traditional Chinese medicine for the clinical treatment of coronary heart disease. However, the mechanism of TPHXR treatment of atherosclerosis (AS) has not been fully elucidated. In this study, we have aimed to explore the potential antiatherosclerotic effect of TPHXR and its underlying mechanisms. Male ApoE knockout (ApoE^-/- ) mice were fed a high-fat diet for 12 weeks and were randomly divided into four groups: the control group, and the low-dose, medium-dose, and high-dose TPHXR groups. The nitric oxide (NO) levels in arterial tissue and human umbilical vein endothelial cells (HUVECs) were measured by diaminofluorescein-2 diacetate staining. Vasorelaxation of mice aorta was performed by wire myograph. Inflammatory cytokines, including tumor necrosis factor-α (TNF-α), hs-CRP, IL-6, and IL-1β, in mice plasma were analyzed by enzyme-linked immunosorbent assay. Western blot analysis was applied to observe protein expression. Oil Red O staining was utilized for the quantification of atherosclerotic plaques. Results showed that 4 weeks of high- and medium-dose TPHXR treatment by oral gavage reduced atheromatous lesions in ApoE ^-/- mice. The high- and medium-dose TPHXR treatment, but not the low-dose treatment, promoted eNOS phosphorylation, increased NO levels and improved endothelium-dependent vasorelaxation in ApoE ^-/- mice. High- and medium-dose TPHXR, but not low-dose TPHXR, decreased the expression of cav-1, NF-κB p50, NF-κB p65, ICAM1, VCAM-1, TNF-α, IL-6, and IL-1β in the vasculature of ApoE ^-/- mice. Enzyme-linked immunosorbent assay analysis indicated that high- and medium-dose TPHXR decreased the levels of TNF-α, IL-6, hs-CRP, and IL-1β. In conclusion, our findings show that TPHXR improved the endothelial function and reduced atheromatous lesions in ApoE ^-/- mice. This result may be due to the decreased expression of caveolin-1 and NF-κB and, hence, the attenuated inflammatory response in AS mice vasculature. TPHXR may represent a promising intervention in patients with AS.

Regulation of Cell Behavior by Hydrostatic Pressure

Hydrostatic pressure (HP) regulates diverse cell behaviors including differentiation, migration, apoptosis, and proliferation. Abnormal HP is associated with pathologies including glaucoma and hypertensive fibrotic remodeling. In this review, recent advances in quantifying and predicting how cells respond to HP across several tissue systems are presented, including tissues of the brain, eye, vasculature and bladder, as well as articular cartilage. Finally, some promising directions on the study of cell behaviors regulated by HP are proposed.

Resting heart rate and the risk of hypertension and heart failure: a dose-response meta-analysis of prospective studies

BACKGROUND

Studies on the relationship of resting heart rate to the risks of hypertension and heart failure have been inconsistent, and the question as to whether there is a linear association between them is unanswered.

OBJECTIVE

To evaluate this possible relationship, we carried out a dose-response meta-analysis of studies that looked at risks associated with resting heart rate and hypertension or heart failure.

METHODS

We searched PubMed, Embase, CNKI and WanFang databases for articles published before 15 June 2017. A random-effect model was used to pool relative risks and 95% confidence intervals. Restricted cubic spline analysis was used to model the resting heart rate-hypertension and heart failure risk association.

RESULTS

We identified 13 and 17 cohort studies for hypertension and heart failure, respectively. The risk for each disease, respectively, increased by 11% relative risk: 1.11 (95% confidence interval: 1.07-1.15) and 19% relative risk: 1.19 (95% confidence interval: 1.13-1.25) for each 10 beats-per-minute increment in resting heart rate. The relationship between resting heart rate and hypertension or heart failure was consistent in most subgroup analyses except for gender subgroups, with no significant association observed in the women subgroup. The results provide no evidence of a nonlinear association of elevated resting heart rate with hypertension and heart failure risk.

CONCLUSION

Resting heart rate shows a linear positive association with the incidence of hypertension and heart failure.

Semaglutide as a promising antiobesity drug

Semaglutide is a glucagon-like peptide-1 receptor agonist (GLP-1 RA) with a long elimination half-life, allowing subcutaneous (sc) administration once per week. Both the European Medicines Agency (EMA) and the Food and Drug Administration (FDA) recently approved once-weekly sc semaglutide for the treatment of type 2 diabetes mellitus (T2DM). The weight loss efficacy of once-weekly sc semaglutide appears to be superior compared with the other once-weekly GLP-1 RAs in patients with T2DM. Semaglutide was recently evaluated as an antiobesity drug in a phase II dose-finding trial, which demonstrated superior weight loss efficacy of once daily sc semaglutide compared with both placebo and once daily 3.0 mg liraglutide in patients with obesity but without T2DM. The magnitude of semaglutide-induced weight loss in this study exceeded the criteria of both the EMA and FDA for antiobesity drugs, and there were no safety concerns, indicating the eligibility of once daily sc semaglutide as a future antiobesity drug.

Differential impacts of brain stem oxidative stress and nitrosative stress on sympathetic vasomotor tone

Based on work-done in the rostral ventrolateral medulla (RVLM), this review presents four lessons learnt from studying the differential impacts of oxidative stress and nitrosative stress on sympathetic vasomotor tone and their clinical and therapeutic implications. The first lesson is that an increase in sympathetic vasomotor tone because of augmented oxidative stress in the RVLM is responsible for the generation of neurogenic hypertension. On the other hand, a shift from oxidative stress to nitrosative stress in the RVLM underpins the succession of increase to decrease in sympathetic vasomotor tone during the progression towards brain stem death. The second lesson is that, by having different cellular sources, regulatory mechanisms on synthesis and degradation, kinetics of chemical reactions, and downstream signaling pathways, reactive oxygen species and reactive nitrogen species should not be regarded as a singular moiety. The third lesson is that well-defined differential roles of oxidative stress and nitrosative stress with distinct regulatory mechanisms in the RVLM during neurogenic hypertension and brain stem death clearly denote that they are not interchangeable phenomena with unified cellular actions. Special attention must be paid to their beneficial or detrimental roles under a specific disease or a particular time-window of that disease. The fourth lesson is that, to be successful, future antioxidant therapies against neurogenic hypertension must take into consideration the much more complicated picture than that presented in this review on the generation, maintenance, regulation or modulation of the sympathetic vasomotor tone. The identification that the progression towards brain stem death entails a shift from oxidative stress to nitrosative stress in the RVLM may open a new vista for therapeutic intervention to slow down this transition.

Resting Heart Rate and Long-term Outcomes Among the African American Population: Insights From the Jackson Heart Study

Importance

Increased resting heart rate is associated with worse outcomes in studies of mostly white populations, but its significance is not well established in African Americans persons whose cardiac comorbidities and structural abnormalities differ.

Objective

To study the prognostic utility of heart rate in a community-based African American cohort in the Jackson Heart Study.

Design, Setting, and Participants

A total of 5261 participants in the Jackson Heart Study, a prospective, community-based study in Jackson, Mississippi, were evaluated. Baseline heart rate was assessed by quintiles and as a continuous variable. All participants with baseline heart rate documented by a 12-lead electrocardiogram without pacing or atrial fibrillation noted on their baseline Jackson Heart Study examination were included in the study. Follow-up began September 26, 2000, and was completed December 31, 2011. Data analysis was performed from July to October 2015.

Main Outcomes and Measures

Unadjusted and adjusted associations between heart rate and all-cause mortality and heart failure hospitalization using Cox proportional hazards regression models.

Results

Of the 5261 individuals included in the analysis, 1921 (36.5%) were men; median (25th-75th percentile) age was 55.7 (45.4-64.8) years. Median (25th-75th percentile) baseline heart rate was 63 beats per minute (bpm) (57-71 bpm). The highest heart rate quintile (73-118 bpm) had higher rates of diabetes (398 [37.4%]; P < .001) and hypertension (735 [69.1%]; P < .001), higher body mass index (median [IQR], 32.4 [28.1-38.3]; P < .001), less physical activity (0 hours per week, 561 [52.8%]; P < .001), and lower β-blocker use (73 [6.9%]; P < .001) compared with lower quintiles. Caffeine intake (from 80.7 to 85.5 mg/d; P = .57) and left ventricular ejection fraction (from 62% to 62.3%; P = .01) were similar between groups. As a continuous variable, elevated heart rate was associated with increased mortality and heart failure hospitalizations, with adjusted hazard ratios for every 5-bpm increase of 1.14 (95% CI, 1.10-1.19) and 1.10 (95% CI, 1.05-1.16), respectively. Similar patterns were observed in comparisons between the highest and lowest quintiles.

Conclusions and Relevance

Higher baseline heart rate was associated with increased mortality and heart failure hospitalizations among African American participants in the Jackson Heart Study. These findings are similar to those seen in white populations, but further study is needed to understand whether African American individuals benefit from interventions targeting heart rate reduction.

Admission Heart Rate Is Associated With Coronary Artery Disease Severity and Complexity in Patients With Acute Coronary Syndrome

We evaluated the relationship between admission heart rate (HR) and coronary artery disease severity and complexity in patients with acute coronary syndrome (ACS). A total of 884 patients (mean age 59 [11] years, 24.7% female) who underwent coronary angiography for ACS and were treated with primary or selective percutaneous coronary intervention were included in this cross-sectional study. The measurement of admission HR was based on the first available resting electrocardiogram after admission. The SYNTAX score (SS) was calculated. Patients with an SS ≤ 22 (n = 538) were classified as the low SS group and those with an SS > 22 (n = 346) were classified as the intermediate-to-high SS group. Admission HR was greater in the intermediate-to-high SS group compared with the low SS group (75 [10] bpm vs 67 [8] bpm, P < .001). Admission HR was positively and significantly correlated with the SS (r = 0.475, P < .001). After multivariate analysis, admission HR (per 1 standard deviation, ie, 10 bpm) remained an independent predictor of intermediate-to-high SS (odds ratio: 3.135, 95% confidence interval: 2.538-3.873, P < .001). Admission HR is independently and positively associated with the SS. Thus, elevated admission HR may be useful to identify patients with ACS with a high coronary atherosclerotic plaque burden.

Higher heart rates increase risk of diabetes and cardiovascular events: A prospective cohort study among Inner Mongolians

AIM

The study examined the association between resting heart rate and risk of type 2 diabetes (T2D) and cardiovascular events in an Inner Mongolian population.

METHODS

Based on a cross-sectional survey carried out in 2003, 2530 participants were reinvestigated between 2013 and 2014. All participants were classified into four groups (quartiles) according to heart rate. Primary outcomes were hypertension, T2D, major macrovascular events and all-cause deaths. Logistic regression models were used to estimate odds ratios (ORs), and shape-restricted cubic spline regressions were conducted to investigate the associations between resting heart rate and study outcomes.

RESULTS

During the 10-year follow-up, 502 (41.6%) patients developed hypertension, 200 (10.4%) had diabetes, 464 (18.3%) experienced major macro-vascular events and 306 (14.3%) died. Resting heart rate was significantly associated with an increased risk of hypertension, T2D, major macro-vascular events and all-cause deaths: adjusted ORs (95% CI) for the highest vs lowest quartiles of heart rate were 1.51 (1.06-2.15), 2.44 (1.54-3.85), 1.55 (1.14-2.10) and 1.57 (1.05-2.34), respectively. Multivariable-adjusted restricted cubic spline regression models showed a linear association between heart rate and the four outcomes (all P < 0.05 for linearity). The addition of heart rate to basic risk factors improved the prediction of risk of diabetes and all-cause deaths [indices of continuous net reclassification improvement and of integrated discrimination improvement were 21.92% (P = 0.002) and 22.69% (P < 0.001), and 0.72% (P = 0.01) and 0.58% (P = 0.03), respectively].

CONCLUSION

Higher heart rates were associated with an increased risk of hypertension, T2D, major macro-vascular events and all-cause deaths among Inner Mongolians, suggesting that heart rate measurement may be of value as a potential clinical and diagnostic marker.

The Association between Resting Heart Rate and Urinary Albumin/Creatinine Ratio in Middle-Aged and Elderly Chinese Population: A Cross-Sectional Study

OBJECTIVE

In general population, resting heart rate (RHR) is associated with cardiovascular disease. However, its relation to chronic kidney disease (CKD) is debated. We therefore investigated the relationship between RHR and urinary albumin/creatinine ratio (UACR, an indicator of early kidney injury) in general population at different levels of blood pressure and blood glucose.

METHODS

We screened out 32,885 subjects from the REACTION study after excluding the subjects with primary kidney disease, heart disease, tumor history, related drug application, and important data loss. The whole group was divided into four groups (Q1: RHR ≤ 71, Q2: 72 ≤ RHR ≤ 78, Q3: 79 ≤ RHR ≤ 86, and Q4: 87 ≤ RHR) according to the quartile of average resting heart rate. The renal function was evaluated by UACR (divided by quartiles of all data in the center to which the subject belonged). Ordinary logistic regression was carried out to explore the association between RHR and UACR at diverse blood pressure and blood glucose levels.

RESULTS

The subjects with higher RHR quartile tend to have a higher UACR, even multifactors were adjusted. After stratifying the subjects according to blood pressure and blood glucose, the positive relationship between RHR and UACR remained in the subjects with normal blood pressure and normal glucose tolerance, while in the hypertension (SBP ≥ 140 mmHg and/or DBP ≥ 90 mmHg) group and the diabetic mellitus (FPG ≥ 7.0 mmol/L and/or PPG ≥ 11.1 mmol/L) group, the relationship disappeared. In the subjects without hypertension, compared with the Q1 group, the UACR is significant higher in the Q3 group (OR: 1.11) and the Q4 group (OR: 1.22). In the subjects with normal glucose tolerance (NGT), compared with the Q1 group, the UACR is significantly higher in the Q3 group (OR: 1.13) and the Q4 group (OR: 1.19).

CONCLUSIONS

The population with higher RHR tend to have a higher UACR in the normal blood pressure group and the normal glucose tolerance group.

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.