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

Comprehensive characterization of cardiac contraction for improved post-infarction risk assessment

This study aims at identifying risk-related patterns of left ventricular contraction dynamics via novel volume transient characterization. A multicenter cohort of AMI survivors (n = 1021) who underwent Cardiac Magnetic Resonance (CMR) after infarction was considered for the study. The clinical endpoint was the 12-month rate of major adverse cardiac events (MACE, n = 73), consisting of all-cause death, reinfarction, and new congestive heart failure. Cardiac function was characterized from CMR in 3 potential directions: by (1) volume temporal transients (i.e. contraction dynamics); (2) feature tracking strain analysis (i.e. bulk tissue peak contraction); and (3) 3D shape analysis (i.e. 3D contraction morphology). A fully automated pipeline was developed to extract conventional and novel artificial-intelligence-derived metrics of cardiac contraction, and their relationship with MACE was investigated. Any of the 3 proposed directions demonstrated its additional prognostic value on top of established CMR indexes, myocardial injury markers, basic characteristics, and cardiovascular risk factors (P < 0.001). The combination of these 3 directions of enhancement towards a final CMR risk model improved MACE prediction by 13% compared to clinical baseline (0.774 (0.771-0.777) vs. 0.683 (0.681-0.685) cross-validated AUC, P < 0.001). The study evidences the contribution of the novel contraction characterization, enabled by a fully automated pipeline, to post-infarction assessment.

Relationship between resting heart rate and long-term outcomes in stabilized patients with myocardial infarction: A prospective community-based cohort study

BACKGROUND

Resting heart rate (RHR) during hospitalization has been shown to be associated with adverse outcomes in patients with myocardial infarction (MI). This study aimed to evaluate the long-term prognostic effect of RHR during the stable phase after MI in post-MI patients.

METHODS

Patients who had prior or new-onset MI and RHR measurements during the stable period after MI between 2006 and 2018 in the community-based Kailuan Study were enrolled. RHR was divided into four groups based on quartiles. Cox regression analysis was used to analyze the association of RHR with primary composite outcome of all-cause death, hospitalization for heart failure (HF), stroke, and recurrent MI and its components.

RESULTS

A total of 4447 post-MI patients were included. During a median follow-up of 7.5 years, 1813 patients (40.8%) developed primary outcomes. Compared to RHR ≤67 bpm, patients with 72 < RHR ≤80 bpm and RHR >80 bpm had increased risks of primary outcome, with adjusted hazard ratios (95% confidence intervals) of 1.23 (1.08-1.40) and 1.35 (1.18-1.55), respectively. The risk of primary outcome increased by 12% (1.07-1.17) for each 10-bpm increase in RHR. Similar results were observed in all-cause death and hospitalization for HF. Restricted cubic splines revealed a linear relationship between RHR and primary outcome, all-cause death, and hospitalization for HF (P for nonlinearity >0.05).

CONCLUSIONS

RHR during the stable phase after MI was an independent predictor for primary outcome and all-cause death in post-MI patients, and RHR >72 bpm was associated with increased risk for primary outcome and all-cause death.

Influence of the Apelinergic System on Conduction Disorders in Patients after Myocardial Infarction

BACKGROUND

There is a growing body of evidence for an important role of the apelinergic system in the modulation of cardiovascular homeostasis. The aim of our study was to (1) examine the relationship between apelin serum concentration at index myocardial infarction (MI) and atrioventricular conduction disorders (AVCDs) at 12-month follow-up, and (2) investigate the association between initial apelin concentration and the novel marker of post-MI scar (Q/QRS ratio) at follow-up.

METHODS

In 84 patients with MI with complete revascularization, apelin peptide serum concentrations for apelin-13, apelin-17, elabela (ELA) and apelin receptor (APJ) were measured on day one of hospitalization; at 12-month follow-up, 54 of them underwent thorough examination that included 12-lead electrocardiography (ECG), Holter ECG monitoring and echocardiography.

RESULTS

The mean age was 58.9 years. At 12-month follow-up, AVCDs were diagnosed in 21.4% of subjects, with AV first-degree block in 16.7% and sinoatrial arrest in 3.7%. ELA serum concentration at index MI correlated positively with the occurrence of AVCD (p = 0.003) and heart rate (p = 0.005) at 12-month follow-up. The apelin-13 serum concentration at index MI correlated negatively with the Q/QRS ratio.

CONCLUSIONS

The apelin peptide concentration during an acute phase of MI impacts the development of AVCD and the value of Q/QRS ratio in MI survivors.

Ivabradine in patients with acute ST-elevation myocardial infarction: a meta-analysis of randomized controlled trials

BACKGROUND

Elevated resting heart rate (HR) predicts poor outcomes in patients with coronary artery disease. Ivabradine has been recommended as a second-line anti-anginal agent in chronic coronary syndrome, while there are no clear indications for acute ST-elevation myocardial infarction (STEMI).

RESULTS

We systematically searched PubMed, Medline, EMBASE, Clinical Trials.gov, and the Cochrane Central Register of Controlled Trials with search terms Ivabradine and Acute myocardial infarction. There are two study outcomes from this study: therapeutic and safety effects. Therapeutic effects include the efficacy of Ivabradine on HR, all-cause mortality, heart failure incidence, left ventricular function and remodeling. Safety effects include troponin levels and ischemic events (recurrent angina pectoris). A total of 6 RCTs was included and showed that Ivabradine was associated with greater resting HR reduction [MD - 5.40; 95%CI - 8.60, - 2.20], improvement of left ventricular ejection fraction [MD 2.98; 95%CI 0.44, 5.51], and left ventricular end systolic volume [MD - 3.81; 95%CI - 6.88, - 0.75]. However, Ivabradine had no impact on all-cause mortality [OR 0.76; 95%CI 0.35, 1.67], heart failure incidence [OR 0.61; 95%CI 0.21, 1.80], and recurrent angina pectoris [OR 0.71; 95%CI 0.50, 1.00].

CONCLUSIONS

Ivabradine is safe and effective for resting HR reduction in patients with STEMI; however, it has no significant influence on mortality. These results suggest that an elevated HR is only a marker of risk but not a modifiable determinant of outcomes in patients who have suffered an acute myocardial infarction.

Cardiorespiratory Interaction and Autonomic Sleep Quality Improve during Sleep in Beds Made from Pinus cembra (Stone Pine) Solid Wood

Cardiorespiratory interactions (CRIs) reflect the mutual tuning of two important organismic oscillators—the heartbeat and respiration. These interactions can be used as a powerful tool to characterize the self-organizational and recreational quality of sleep. In this randomized, blinded and cross-over design study, we investigated CRIs in 15 subjects over a total of 253 nights who slept in beds made from different materials. One type of bed, used as control, was made of melamine faced chipboard with a wood-like appearance, while the other type was made of solid wood from stone pine (Pinus cembra). We observed a significant increase of vagal activity (measured by respiratory sinus arrhythmia), a decrease in the heart rate (as an indicator of energy consumption during sleep) and an improvement in CRIs, especially during the first hours of sleep in the stone pine beds as compared to the chipboard beds. Subjective assessments of study participants’ well-being in the morning and sub-scalar assessments of their intrapsychic stability were significantly better after they slept in the stone pine bed than after they slept in the chipboard bed. Our observations suggest that CRIs are sensitive to detectable differences in indoor settings that are relevant to human health. Our results are in agreement with those of other studies that have reported that exposure to volatile phytochemical ingredients of stone pine (α-pinene, limonene, bornyl acetate) lead to an improvement in vagal activity and studies that show a reduction in stress parameters upon contact with solid wood surfaces.

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.

Cardiovascular Reactivity to Acute Mental Stress: THE IMPORTANCE OF TYPE D PERSONALITY, TRAIT ANXIETY, AND DEPRESSION SYMPTOMS IN PATIENTS AFTER ACUTE CORONARY SYNDROMES

PURPOSE

Links between psychophysiological reactions to stress stimuli and perceived mental distress, including type D personality, anxiety, and depression, are still under debate. The aim of this study was to examine associations between cardiovascular reactivity to social stress and mental distress in patients after acute coronary syndrome.

METHODS

Patients (n = 116, 86% males, 52 ± 8 yr) with coronary artery disease 2 wk after acute coronary syndrome were evaluated for sociodemographic, clinical characteristics and coronary artery disease risk factors. The Trier Social Stress Test was employed to measure cardiovascular reactions to social stress (systolic and diastolic blood pressure and heart rate). Mental distress assessment included type D personality (Type D Scale), anxiety and depressive symptoms (Hospital Anxiety and Depression Scale), and state and trait anxiety (State-Trait Anxiety Inventory).

RESULTS

Multiple linear regression analysis showed associations between type D personality and lower heart rate during Trier Social Stress Test periods of task instruction (β = -.196, P < .04), preparation time (β = -.232, P < .01), and recovery time (β = -.209, P < .029). Higher trait anxiety was linked with lower heart rate during baseline rest (β = -.287, P < .01), task instruction (β = -.286, P < .01), preparation time (β = -.241, P < .01), and recovery period (β = -.209, P < .05). Depressive symptoms were associated with higher systolic blood pressure during baseline rest (β =.187, P < .05), task instruction (β = .306 P < .01), and free speech (β = .264, P < .05).

CONCLUSIONS

Mental distress was associated with cardiovascular stress reactions independent from possible covariates, suggesting dysregulated psychophysiological reactions to acute stress.

α-Glucosidase inhibitor miglitol attenuates glucose fluctuation, heart rate variability and sympathetic activity in patients with type 2 diabetes and acute coronary syndrome: a multicenter randomized controlled (MACS) study

Background

Little is known about clinical associations between glucose fluctuations including hypoglycemia, heart rate variability (HRV), and the activity of the sympathetic nervous system (SNS) in patients with acute phase of acute coronary syndrome (ACS). This pilot study aimed to evaluate the short-term effects of glucose fluctuations on HRV and SNS activity in type 2 diabetes mellitus (T2DM) patients with recent ACS. We also examined the effect of suppressing glucose fluctuations with miglitol on these variables.

Methods

This prospective, randomized, open-label, blinded-endpoint, multicenter, parallel-group comparative study included 39 T2DM patients with recent ACS, who were randomly assigned to either a miglitol group (n = 19) or a control group (n = 20). After initial 24-h Holter electrocardiogram (ECG) (Day 1), miglitol was commenced and another 24-h Holter ECG (Day 2) was recorded. In addition, continuous glucose monitoring (CGM) was performed throughout the Holter ECG.

Results

Although frequent episodes of subclinical hypoglycemia (≤4.44 mmo/L) during CGM were observed on Day 1 in the both groups (35% of patients in the control group and 31% in the miglitol group), glucose fluctuations were decreased and the minimum glucose level was increased with substantial reduction in the episodes of subclinical hypoglycemia to 7.7% in the miglitol group on Day 2. Holter ECG showed that the mean and maximum heart rate and mean LF/HF were increased on Day 2 in the control group, and these increases were attenuated by miglitol. When divided 24-h time periods into day-time (0700–1800 h), night-time (1800–0000 h), and bed-time (0000–0700 h), we found increased SNS activity during day-time, increased maximum heart rate during night-time, and glucose fluctuations during bed-time, which were attenuated by miglitol treatment.

Conclusions

In T2DM patients with recent ACS, glucose fluctuations with subclinical hypoglycemia were associated with alterations of HRV and SNS activity, which were mitigated by miglitol, suggesting that these pathological relationships may be a residual therapeutic target in such patients.

Trial registration Unique Trial Number, UMIN000005874 (https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000006929)

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-017-0571-1) contains supplementary material, which is available to authorized users.

Increased sympathetic nerve activity and reduced cardiac baroreflex sensitivity in rheumatoid arthritis

KEY POINTS

Rheumatoid arthritis (RA) is a chronic inflammatory condition associated with an increased risk of cardiovascular mortality. Increased sympathetic nerve activity and reduced cardiac baroreflex sensitivity heighten cardiovascular risk, althogh whether such autonomic dysfunction is present in RA is not known. In the present study, we observed an increased sympathetic nerve activity and reduced cardiac baroreflex sensitivity in patients with RA compared to matched controls. Pain was positively correlated with sympathetic nerve activity and negatively correlated with cardiac baroreflex sensitivity. The pattern of autonomic dysfunction that we describe may help to explain the increased cardiovascular risk in RA, and raises the possibility that optimizing pain management may resolve autonomic dysfunction in RA.

ABSTRACT

Rheumatoid arthritis (RA) is a chronic inflammatory condition associated with increased cardiovascular morbidity/mortality and an incompletely understood pathophysiology. In animal studies, central and blood borne inflammatory cytokines that can be elevated in RA evoke pathogenic increases in sympathetic activity and reductions in baroreflex sensitivity (BRS). We hypothesized that muscle sympathetic nerve activity (MSNA) was increased and BRS decreased in RA. MSNA, blood pressure and heart rate (HR) were recorded in age- and sex-matched RA-normotensive (n = 13), RA-hypertensive patients (RA-HTN; n = 17), normotensive (NC; n = 17) and hypertensive controls (HTN; n = 16). BRS was determined using the modified Oxford technique. Inflammation and pain were determined using serum high sensitivity C-reactive protein (hs-CRP) and a visual analogue scale (VAS), respectively. MSNA was elevated similarly in RA, RA-HTN and HTN patients (32 ± 9, 35 ± 14, 37 ± 8 bursts min^-1 ) compared to NC (22 ± 9 bursts min^-1 ; P = 0.004). Sympathetic BRS was similar between groups (P = 0.927), whereas cardiac BRS (cBRS) was reduced in RA, RA-HTN and HTN patients [5(3-8), 4 (2-7), 6 (4-9) ms mmHg^-1 ] compared to NC [11 (8-15) ms mmHg^-1 ; P = 0.002]. HR was independently associated with hs-CRP. Increased MSNA and reduced cBRS were associated with hs-CRP although confounded in multivariable analysis. VAS was independently associated with MSNA burst frequency, cBRS and HR. We provide the first evidence for heightened sympathetic outflow and reduced cBRS in RA that can be independent of hypertension. In RA patients, reported pain was positively correlated with MSNA and negatively correlated with cBRS. Future studies should assess whether therapies to ameliorate pain and inflammation in RA restores autonomic balance and reduces cardiovascular events.