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

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.

Heart rate: control mechanisms, pathophysiology and assessment of the neurocardiac system in health and disease

The monitoring of physiological function and dysfunction is an important principle in modern medicine. Heart rate is a basic example of this type of observation, particularly assessing the neurocardiac system, which entails the autonomic nervous system and intracardiac processes. The neurocardiac axis is an underappreciated and often overlooked system which, if measured appropriately in the clinical setting, may allow identification of patients at risk of disease progression and even mortality. While heart rate itself is a simplistic tool, more information may be gathered through assessing heart rate variability and heart rate recovery time. Studies have demonstrated an association of slow heart rate recovery and lower heart rate variability as markers of elevated sympathetic and lower parasympathetic tone. These parameters have additionally been shown to relate to development of arrhythmia, heart failure, systemic inflammatory processes, ischaemic heart disease and an increased rate of mortality. The aim of this review is to detail how heart rate is homeostatically controlled by the autonomic nervous system, how heart rate can impact on pathophysiological processes, and how heart rate variability and heart rate recovery time may be used in the clinical setting to allow the neurocardiac system to be assessed.

Adaptation of Arterial Wall Viscosity to the Short-Term Reduction of Heart Rate: Impact of Aging

Background Changes in arterial wall viscosity, which dissipates the energy stored within the arterial wall, may contribute to the beneficial effect of heart rate (HR) reduction on arterial stiffness and cardiovascular coupling. However, it has never been assessed in humans and could be altered by aging. We evaluated the effect of a selective HR-lowering agent on carotid arterial wall viscosity and the impact of aging on this effect. Methods and Results This randomized, placebo-controlled, double-blind, crossover study performed in 19 healthy volunteers evaluated the effects of ivabradine (5 mg BID, 1-week) on carotid arterial wall viscosity, mechanics, hemodynamics, and cardiovascular coupling. Arterial wall viscosity was evaluated by the area of the hysteresis loop of the pressure-lumen cross-sectional area relationship, representing the energy dissipated (W_V), and by the relative viscosity (W_V/W_E), with W_E representing the elastic energy stored. HR reduction by ivabradine increased W_V and W_E whereas W_V/W_E remained stable. In middle-aged subjects (n=11), baseline arterial stiffness and cardiovascular coupling were less favorable, and W_E was similar but W_V and therefore W_V/W_E were lower than in youth (n=8). HR reduction increased W_V/W_E in middle-aged but not in young subjects, owing to a larger increase in W_V than W_E. These results were supported by the age-related linear increase in W_V/W_E after HR reduction (P=0.009), explained by a linear increase in W_V. Conclusion HR reduction increases arterial wall energy dissipation proportionally to the increase in W_E, suggesting an adaptive process to bradycardia. This mechanism is altered during aging resulting in a larger than expected energy dissipation, the impact of which should be assessed. Registration URL: https://www.clinicaltrials.gov; Unique identifier: 2015/077/HP. URL: https://www. eudract.ema.europa.eu; Unique identifier: 2015-002060-17.

Protection of Ivabradine Combined with Trimetazidine on Myocardial Injury after Percutaneous Coronary Intervention in Patients with Coronary Artery Disease Evaluated by Magnetic Resonance Image under Convolutional Neural Network

Objective

To evaluate the myocardial protection of Ivabradine (IBD) combined with Trimetazidine (TMZ) in patients with coronary artery disease (CAD) after percutaneous coronary intervention (PCI), magnetic resonance imaging (MRI) images under convolutional neural network (CNN) algorithm were used.

Methods

A CNN artificial intelligence algorithm was proposed to process the image artifacts caused by undersampling magnetic resonance, so as to be used in the diagnosis and efficacy evaluation of myocardial injury. 120 patients with CAD after PCI were rolled into group A (TMZ treatment), group B (IBD treatment), and group C (IBD + TMZ combined treatment) randomly, with 40 patients in each group. All the patients were treated for two consecutive weeks and followed up for six months. Clinical indicators of patients in the two groups were observed, detected, and statistically analyzed.

Results

The accuracy, sensitivity, specificity, and area under the curve (AUC) of MRI images based on CNN algorithm for the diagnosis of myocardial injury were 91.04%, 97.60%, 87.04%, and 96.43%, respectively. After treatment, the left ventricular end diastolic diameter (LVEDD), LVE diastolic volume (LVEDV), LVE systolic diameter (LVESD), and LVE systolic volume (LVESV) were greatly reduced in all groups after treatment, whereas the left ventricular ejection fraction (LVEF) increased considerably (P < 0.05). LVEDD, LVEDV, LVESD, and LVESV in group C were substantially inferior to those in groups A and B, and LVEF was remarkably superior to that in groups A and B (P < 0.05). After treatment, cTnI, hs-CRP, sICAM-1, ET-1, and MDA in three groups were greatly decreased (P < 0.05), while SOD was substantially increased (P < 0.05). After treatment, cTnI, hs-CRP, SICAM-1, ET-1, and MDA in group C were notably inferior to groups A and B (P < 0.05), while SOD was greatly higher (P < 0.05).

Conclusion

MRI based on CNN had high application value in the diagnosis and efficacy evaluation of myocardial injury after PCI. For patients with CAD, IBD combined with TMZ after PCI can effectively play the role of anti-inflammatory and antioxidative damage and improve intradermal function.

Exercise Intolerance in Heart Failure With Preserved Ejection Fraction: Arterial Stiffness and Aabnormal Left Ventricular Hemodynamic Responses During Exercise

BACKGROUND

Arterial stiffness is thought to contribute to the pathophysiology of heart failure with preserved ejection fraction (HFpEF). We sought to examine arterial stiffness in HFpEF and hypertension and investigate associations of arterial and left ventricular hemodynamic responses to exercise.

METHODS AND RESULTS

A total of 385 symptomatic individuals with an EF of ≥50% underwent upright cardiopulmonary exercise testing with invasive hemodynamic assessment of arterial stiffness and load (aortic augmentation pressure, augmentation index, systemic vascular resistance index, total arterial compliance index, effective arterial elastance index, and pulse pressure amplification) at rest and during incremental exercise. An abnormal hemodynamic response to exercise was defined as a steep increase in pulmonary capillary wedge pressure relative to cardiac output (∆PCWP/∆CO > 2 mm Hg/L/min). We compared rest and exercise measures between HFpEF and hypertension in multivariable analyses. Among 188 participants with HFpEF (mean age 61 ± 13 years, 56% women), resting arterial stiffness parameters were worse compared with 94 hypertensive participants (mean age 55 ± 15 years, 52% women); these differences were accentuated during exercise in HFpEF (all P ≤ .0001). Among all participants, exercise measures of arterial stiffness correlated with worse ∆PCWP/∆CO. Specifically, a 1 standard deviation higher exercise augmentation pressure was associated with 2.15-fold greater odds of abnormal LV hemodynamic response (95% confidence interval 1.52-3.05; P < .001). Further, exercise measures of systemic vascular resistance index, elastance index, and pulse pressure amplification correlated with a lower peak oxygen consumption.

CONCLUSIONS

Exercise accentuates the increased arterial stiffness found in HFpEF, which in turn correlates with left ventricular hemodynamic responses. Unfavorable ventricular-vascular interactions during exercise in HFpEF may contribute to exertional intolerance and inform future therapeutic interventions.

Effects of selective heart rate reduction with ivabradine on LV function and central hemodynamics in patients with chronic coronary syndrome

Objectives

We assessed left ventricular (LV) function and central hemodynamic effects in patients with a heart rate (HR) at rest of ≥70 beats per minute (bpm) and chronic coronary syndrome (CCS) after long-term treatment with ivabradine compared to placebo by cardiac magnetic resonance (CMR) imaging.

Methods and results

In a randomized, double-blinded, prospective cross-over design, 23 patients (18 male, 5 female) were treated with ivabradine (7.5 mg bid) or placebo for 6 months. CMR imaging was performed at baseline and after 6 and 12 months to determine LV functional parameters.Mean resting HR on treatment with ivabradine was 58 ± 8.2 bpm and 70.2 ± 8.3 bpm during placebo (p < 0.0001).There was no difference in systolic LV ejection fraction (ivabradine 57.4 ± 11.2% vs placebo 53.0 ± 10.9%, p = 0.18), indexed end-diastolic (EDVi) or end-systolic volumes (ESVi). Indexed stroke volume (SVi) (ml/m²) remained unchanged after treatment with ivabradine. Volume time curve parameters reflecting systolic LV function (peak ejection rate and time) were unaffected by ivabradine, while both peak filling rate (PFR) and PFR/EDV were significantly increased. Mean aortic velocity (cm/s) was significantly reduced during treatment with ivabradine (ivabradine 6.7 ± 2.7 vs placebo 9.0 ± 3.4, p = 0.01). Aortic flow parameters were correlated to parameters of vascular stiffness. The strongest correlation was revealed for mean aortic velocity with aortic distensibility (AD) (r = -0.86 [-0.90 to -0.85], p < 0.0001).

Conclusion

Long-term reduction of HR with ivabradine in patients with CCS improved diastolic function and reduced mean aortic flow velocity.

Effects of adding ivabradine to usual care in patients with angina pectoris: a systematic review of randomised clinical trials with meta-analysis and Trial Sequential Analysis

OBJECTIVE

To determine the impact of ivabradine on outcomes important to patients with angina pectoris caused by coronary artery disease.

METHODS

We conducted a systematic review. We included randomised clinical trials comparing ivabradine versus placebo or no intervention for patients with angina pectoris due to coronary artery disease published prior to June 2020. We used Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, Cochrane methodology, Trial Sequential Analysis, Grading of Recommendations Assessment, Development, and Evaluation, and our eight-step procedure. Primary outcomes were all-cause mortality, serious adverse events and quality of life.

RESULTS

We included 47 randomised clinical trials enrolling 35 797 participants. All trials and outcomes were at high risk of bias. Ivabradine compared with control did not have effects when assessing all-cause mortality (risk ratio [RR] 1.04; 95% CI 0.96 to 1.13), quality of life (standardised mean differences -0.05; 95% CI -0.11 to 0.01), cardiovascular mortality (RR 1.07; 95% CI 0.97 to 1.18) and myocardial infarction (RR 1.03; 95% CI 0.91 to 1.16). Ivabradine seemed to increase the risk of serious adverse events after removal of outliers (RR 1.07; 95% CI 1.03 to 1.11) as well as the following adverse events classified as serious: bradycardia, prolonged QT interval, photopsia, atrial fibrillation and hypertension. Ivabradine also increased the risk of non-serious adverse events (RR 1.13; 95% CI 1.11 to 1.16). Ivabradine might have a statistically significant effect when assessing angina frequency (mean difference (MD) 2.06; 95% CI 0.82 to 3.30) and stability (MD 1.48; 95% CI 0.07 to 2.89), but the effect sizes seemed minimal and possibly without any relevance to patients, and we identified several methodological limitations, questioning the validity of these results.

CONCLUSION

Our findings do not support that ivabradine offers significant benefits on patient important outcomes, but rather seems to increase the risk of serious adverse events such as atrial fibrillation and non-serious adverse events. Based on current evidence, guidelines need reassessment and the use of ivabradine for angina pectoris should be reconsidered.

PROSPERO REGISTRATION NUMBER

CRD42018112082.

Arterial Stiffness Is Associated With Increased Symptom Burden in Patients With Atrial Fibrillation

BACKGROUND

Increased arterial stiffness (AS) has been described as a predictor of atrial fibrillation (AF). This study was performed to assess whether increased AS leads to a higher symptom burden in patients with AF.

METHODS

One hundred sixty-two consecutive patients (104 male, 58 female) with diagnosed AF (paroxysmal or persistent) were enrolled. Symptoms most likely attributable to AF were quantified according to the Canadian Cardiovascular Society Severity of Atrial Fibrillation (SAF) scale. AS indices (aortic distensibility, cyclic circumferential strain, and aortic compliance) were characterized using transoesophageal echocardiography.

RESULTS

The cohort was divided into asymptomatic to oligosymptomatic (SAF scale 0-1, n = 78 [48.1%]) and symptomatic (SAF scale ≥ 2, n = 84 [51.9%]) patients. Symptomatic patients tended to be younger (median, 75 [interquartile range (IQR) 67-80] vs 71 [65-79]; P = 0.047) and were more likely to be female (22 [28.2%] vs 36 [42.9%]; P = 0.052). Hypertension was more frequent in symptomatic patients. Aortic compliance indices each were reduced in symptomatic patients, most pronounced for aortic compliance (median, 0.05 [IQR 0.03-0.06] vs 0.04 [0.03-0.05] cm/mm Hg; P = 0.01) followed by cyclic circumferential strain (median, 0.09 [IQR 0.07-0.11] vs 0.07 [0.04-0.10]; P = 0.02) and aortic distensibility (10^-3 mm Hg^-1, median, 1.74 [IQR 1.34-2.24] vs 1.54 [1.12-2.08]; P = 0.03). Multivariable analysis revealed aortic compliance as an independent predictor for symptoms in patients with AF with an odds ratio of 2.6 (95% confidence interval, 1.2-3.4; P = 0.003).

CONCLUSIONS

AS contributes to a high symptom burden in patients with AF, emphasizing the prognostic role of AS in the early detection and prevention in patients with AF.

Ivabradine and endothelium: an update

Ivabradine is a pure heart-rate lowering drug that is nowadays used, accordingly to the last ESC Guidelines, to reduce mortality and heart failure (HF) hospitalization in patients with HF with reduced ejection fraction and in symptomatic patiens with inappropriate sinus tachycardia. Moreover, interesting effect of ivabradine on endothelial and myocardial function and on oxidative stress and inflamation pathways are progressively emerging. The aim of this paper is to highlight newer evidences about ivabradine effect (and consequently possible future application of the drug) in pathological settings different from guidelines-based clinical practice.

Effects of Whey Protein Supplementation on Aortic Stiffness, Cerebral Blood Flow, and Cognitive Function in Community-Dwelling Older Adults: Findings from the ANCHORS A-WHEY Clinical Trial

ANCHORS A-WHEY was a 12-week randomized controlled trial (RCT) designed to examine the effect of whey protein on large artery stiffness, cerebrovascular responses to cognitive activity and cognitive function in older adults. Methods: 99 older adults (mean ± SD; age 67 ± 6 years, BMI 27.2 ± 4.7kg/m², 45% female) were randomly assigned to 50g/daily of whey protein isolate (WPI) or an iso-caloric carbohydrate (CHO) control for 12 weeks (NCT01956994). Aortic stiffness was determined as carotid-femoral pulse wave velocity (cfPWV). Aortic hemodynamic load was assessed as the product of aortic systolic blood pressure and heart rate (Ao SBP × HR). Cerebrovascular response to cognitive activity was assessed as change in middle-cerebral artery (MCA) blood velocity pulsatility index (PI) during a cognitive perturbation (Stroop task). Cognitive function was assessed using a computerized neurocognitive battery. Results: cfPWV increased slightly in CHO and significantly decreased in WPI (p < 0.05). Ao SBP × HR was unaltered in CHO but decreased significantly in WPI (p < 0.05). Although emotion recognition selectively improved with WPI (p < 0.05), WPI had no effect on other domains of cognitive function or MCA PI response to cognitive activity (p > 0.05 for all). Conclusions: Compared to CHO, WPI supplementation results in favorable reductions in aortic stiffness and aortic hemodynamic load with limited effects on cognitive function and cerebrovascular function in community-dwelling older adults.

Pharmacokinetic profile of ivabradine hemisulfate sustained-release tablets administered in Chinese healthy volunteers: An open-label, randomized, single-dose, three-period crossover study

We aimed to determine the pharmacokinetics and safety of three single oral doses (5, 10 and 15 mg) of ivabradine hemisulfate sustained-release tablets in healthy Chinese volunteers. A total of 12 volunteers (six males and six females) were randomized to receive a single oral dose of ivabradine hemisulfate sustained-release tablets 5, 10 or 15 mg, with a 1-week washout between periods. Blood samples were collected at regular intervals from 0 to 48 h after drug administration, and the concentrations of ivabradine and N-desmethyl ivabradine were determined by HPLC-tandem mass spectrometry. Pharmacokinetic parameters were estimated by non-compartmental analysis. After administering single doses of 5, 10 and 15 mg, the mean maximum concentration (C_max ) levels of ivabradine were 4.36, 7.29 and 12.62 ng/mL, and the mean area under the curve from time 0 to 48 h (AUC_0-48 ) values were 55.66, 101.16 and 182.09 h·ng/mL, respectively. The mean C_max levels of N-desmethyl ivabradine were 1.05, 2.03 and 3.16 ng/mL, and the mean AUC_0-48 values were 20.61, 39.44 and 65.72 h·ng/mL, respectively. The median time of maximum concentration (T_max ) levels of ivabradine and N-desmethyl ivabradine were 5 h for all three doses tested. The pharmacokinetic properties of ivabradine hemisulfate sustained-release tablets were linear at doses from 5 to 15 mg. Ivabradine hemisulfate sustained-release tablet appears to be well tolerated in these healthy volunteers.

Validation of simple measures of aortic distensibility based on standard 4-chamber cine CMR: a new approach for clinical studies

Objective

Aortic distensibility (AD) represents a well-established parameter of aortic stiffness. It remains unclear, however, whether AD can be obtained with high reproducibility in standard 4-chamber cine CMR images of the descending aorta. This study investigated the intra- and inter-observer agreement of AD based on different angles of the aorta and provided a sample size calculation of AD for future trials.

Methods

Thirty-one patients underwent CMR. Angulation of the descending aorta was performed to obtain strictly transversal and orthogonal cross-sectional aortic areas. AD was obtained both area and diameter based.

Results

For area-based values, inter-observer agreement was highest for 4-chamber AD (ICC 0.97; 95% CI 0.93–99), followed by orthogonal AD (ICC 0.96; 95% CI 0.91–98) and transversal AD (ICC 0.93; 95% CI 0.80–97). For diameter-based values, agreement was also highest for 4-chamber AD (ICC 0.97; 95% CI 0.94–99), followed by orthogonal AD (ICC 0.96; 95% CI 0.92–98) and transversal AD (ICC 0.91; 95% CI 0.77–96). Bland–Altman plots confirmed a small variation among observers. Sample size calculation showed a sample size of 12 patients to detect a change in 4-chamber AD of 1 × 10⁻³ mmHg⁻¹ with either the area or diameter approach.

Conclusion

AD measurements are highly reproducible and allow an accurate and rapid assessment of arterial compliance from standard 4-chamber cine CMR.

Graphic abstract

Electronic supplementary material

The online version of this article (10.1007/s00392-019-01525-8) contains supplementary material, which is available to authorized users.