Angina Severity, Mortality, and Healthcare Utilization Among Veterans With Stable Angina

Minimal clinically important differences in patient-reported outcomes after coronary artery bypass surgery in the arterial revascularization trial

OBJECTIVES

This article identifies minimal clinically important differences (MCIDs) in quality of life (QoL) measures among patients who had coronary artery bypass grafting (CABG) and were enrolled in the arterial revascularization trial (ART).

METHODS AND RESULTS

The European Quality of Life-5 Dimensions (EQ-5D) and the Short Form Health Survey 36-Item (SF-36) physical component (PC) and mental component (MC) scores were recorded at baseline, 5 years and 10 years in ART. The MCIDs were calculated as changes in QoL scores anchored to 1-class improvement in the New York Heart Association functional class and Canadian Cardiovascular Society scale at 5 years. Cox proportional hazard models were used to evaluate associations between MCIDs and mortality. Patient cohorts were examined for the SF-36 PC (N = 2671), SF-36 MC (N = 2815) and EQ-5D (N = 2943) measures, respectively. All QoL scores significantly improved after CABG compared to baseline. When anchored to the New York Heart Association, the MCID at 5 years was 17 (95% confidence interval: 17-20) for SF-36 PC, 14 (14-17) for the SF-36 MC and 0.12 (0.12-0.15) for EQ-5D. Using the Canadian Cardiovascular Society scale as an anchor, the MCID at 5 years was 15 (15-17) for the SF-36 PC, 12 (13-15) for the SF-36 MC and 0.12 (0.11-0.14) for the EQ-5D. The MCIDs for SF-36 PC and EQ-5D at 5 years were associated with a lower risk of mortality at the 10-year follow-up point after surgery.

CONCLUSIONS

MCIDs for CABG patients have been identified. These thresholds may have direct clinical applications in monitoring patients during follow-up and in designing new trials that include QoL as a primary study outcome.

CLINICAL TRIAL REGISTRATION NUMBER

ISRCTN46552265.

Exploring the retrospective and prospective associations between the big five personality traits and clinical diagnosis of angina in middle-aged and older adults

OBJECTIVE

The goal of the present research was to test the retrospective and prospective associations between the Big Five personality traits and clinical diagnosis of angina while controlling for demographic characteristics.

METHODS

Data from middle-aged and older adults from a cohort study Understanding Society: the UK Household Longitudinal Study (UKHLS) were extracted and analyzed using binary logistic regressions (N = 10,124 for the retrospective study and N = 5485 for the prospective study). Personality was measured using a self-report 15-item version of the Big Five inventory between 2011 and 2012. Angina was measured by a self-report clinical diagnosis history question in each wave from until 2019. Covariates in our models included age, sex, income (monthly), education, and marital status.

RESULTS

Neuroticism was positively related to the likelihood of clinical angina diagnosis in both the retrospective (OR = 1.22, 95% C.I. [1.11, 1.34]) and the prospective (OR = 1.52, 95% C.I. [1.19, 1.94]) study whereas Extraversion had a positive association with odds of angina (OR = 1.52, 95% C.I. [1.17, 1.97]) in the prospective study only. The negative association between Openness and clinical angina diagnosis in the cross-sectional analysis is borderline significant (OR = 0.91, p = 0.048, 95% C.I. [0.83, 1.00]).

CONCLUSION

Our research indicated that personality traits are associated with the risk of angina. These findings emphasize the importance of considering personality traits in understanding the etiology of angina and potentially informing personalized prevention and intervention strategies.

Effectiveness of Device-Guided Breathing in Chronic Coronary Syndrome: A Randomized Controlled Study

Background

Chronic coronary syndrome (CCS) is one of the most life-restricting coronary artery diseases, and symptom relief is the main goal in CCS patients who suffer from angina.

Objectives

To assess the potential benefits of device-guided breathing in CCS patients with angina in this randomized, controlled, single-blinded study.

Methods

Fifty-one patients with CCS received device-guided breathing for 7 days/8 weeks. Exercise capacity [exercise stress test], cardiac function [transthoracic echocardiography], and angina severity [Canadian Cardiovascular Society Classification] were evaluated initially and after the training. Device-guided breathing was performed at the lowest resistance of the device (POWERbreathe® Classic LR) for the control group (n = 17). The low load training group (LLTG; n = 18) and high load training group (HLTG; n = 16) were trained at 30% and 50% of maximal inspiratory pressure. Baseline characteristics were compared using one-way ANOVA and Kruskal-Wallis test. Categorical data were compared using the chi-square test. ANCOVA was performed to compare changes between three groups. A p value < 0.05 was considered statistically significant.

Results

Metabolic equivalent values were significantly improved in both HLTG and LLTG groups (p < 0.001, p = 0.003). The Duke treadmill score significantly improved and shifted to low-risk both in the HLTG (p < 0.001) and LLTG (p < 0.001) groups. Angina severity significantly alleviated after the training in both HLTG and LLTG groups (p < 0.001, p = 0.002).

Conclusions

An 8-week long program of short-term respiratory muscle training provided positive gains in exercise capacity and angina severity in CCS patients with angina. The effects of long-term training programs on CCS patients should be investigated clinically because of the possibility of helping to decrease the need for invasive treatments.

Contemporary Risk Stratification of Acute Coronary Syndrome

Chest pain is one of the most common presenting concerns of patients seeking care in the emergency department, and the underlying etiology can range from acute coronary syndrome to various other non-cardiac causes. Initial evaluation should focus on characterizing symptoms and identifying risk factors, but further risk stratification using clinical decision pathways and biomarkers (cardiac troponin) is essential. The 2021 American Heart Association/American College of Cardiology guidelines for the evaluation and diagnosis of chest pain represent the first ever guidelines for the evaluation of patients with acute chest pain. The contemporary risk stratification methods described in these guidelines allow for the identification of patient subgroups: patients who do not require further testing, patients who should proceed directly to the cath lab, and patients who will benefit from further anatomic or functional testing. In this review, we describe contemporary risk stratification methods for acute coronary syndrome and summarize the recommendations put forth by the guidelines.

No Healthcare Utilization and Death

BACKGROUND

An inappropriately low frequency of healthcare utilization has been reported to be associated with poor control of chronic diseases, accelerating healthcare disparities. However, the evidence is limited regarding the association between no healthcare utilization and mortality.

OBJECTIVES

To examine whether individuals without healthcare utilization have the increased risks of mortality among the US general population.

DESIGN

Prospective cohort study PARTICIPANTS: Adults aged ≥ 20 years (n = 39,067) in the National Health and Nutrition Examination Survey (NHANES)1999-2014 linked to national mortality data through December 2015.

MAIN MEASURES

The exposure was the number of visits to healthcare providers during the past year (healthcare utilization): none, 1-3 times (referent), 4-9 times, or ≥ 10 times. Cox hazard regression models were employed to estimate the adjusted hazard ratios (aHR) of all-cause, cardiovascular, and cancer mortality adjusting for socio-demographic characteristics and comorbidities.

KEY RESULTS

During a median follow-up of 7.4 years, participants without visit over the past year showed higher risks of all-cause mortality (aHR [95% CI] = 1.16 [1.04-1.30]) and cardiovascular mortality (aHR [95% CI] = 1.62 [1.28-2.05]) than those who visited the office 1-3 times. We found no evidence of the association between no visit and cancer mortality. The association between no providers' office visit and all-cause mortality was stronger among males (aHR [95% CI] = 1.22 [1.06-1.40]) than females (aHR [95% CI] = 0.97 [0.79-1.19]; p-for-interaction = 0.01) and among uninsured individuals (aHR [95% CI] = 1.22 [0.98-1.51]) than insured individuals (aHR [95% CI] = 1.09 [0.95-1.25]; p-for-interaction = 0.04).

CONCLUSION

No providers' office visit over a year was associated with increased risks of all-cause and cardiovascular mortality. Further investigations are warranted to identify the underlying reasons for the elevated mortality risks due to no healthcare utilization.

Correlation of the disease-specific Canadian Cardiovascular Society (CCS) classification and health-related quality of life (15D) in coronary artery disease patients

Background

Generic health-related quality of life (HRQoL) and disease-specific instruments measure HRQoL from different aspects, although generic instruments often contain dimensions that reflect common symptoms. We evaluated how the change in 15D HRQoL and Canadian Cardiovascular Society (CCS) grading of angina severity correlate among coronary artery disease patients during 12-month follow-up.

Methods

Altogether 1 271 patients scheduled for coronary angiography between June 2015 and February 2017 returned the 15D HRQoL and CCS questionnaires before angiography and after one-year follow-up as a part of routine clinical practice. Spearman correlations between one-year changes in the CCS and the 15D and its dimensions were evaluated. Changes in 15D were classified into 5 categories based on the reported minimal important difference (MID) for the instrument.

Results

Change in the CCS grade correlated moderately with the MID-based change in the 15D (r = 0.33, 95% confidence interval 0.27–0.39). Correlations between these instruments were similar in different age groups, between sexes and treatment modalities. Of the individual 15D dimensions, changes in breathing (r = 0.40) and vitality (r = 0.30) had the strongest correlations with CCS change.

Conclusion

The symptom-based evaluation of the change in the CCS grade may not catch the full benefit or harm of the treatment and vice versa, a generic instrument, such as 15D, likely does not fully capture change in disease-specific symptoms. Thus, generic and disease-specific instruments are complementary and should be used in conjunction.

Reversing mitochondrial defects in aged hearts: role of mitochondrial calpain activation

Aging chronically increases endoplasmic reticulum (ER) stress that contributes to mitochondrial dysfunction. Activation of calpain 1 (CPN1) impairs mitochondrial function during acute ER stress. We proposed that aging-induced ER stress led to mitochondrial dysfunction by activating CPN1. We posit that attenuation of the ER stress or direct inhibition of CPN1 in aged hearts can decrease cardiac injury during ischemia-reperfusion by improving mitochondrial function. Male young (3 mo) and aged mice (24 mo) were used in the present study, and 4-phenylbutyrate (4-PBA) was used to decrease the ER stress in aged mice. Subsarcolemmal (SSM) and interfibrillar mitochondria (IFM) were isolated. Chronic 4-PBA treatment for 2 wk decreased CPN1 activation as shown by the decreased cleavage of spectrin in cytosol and apoptosis inducing factor (AIF) and the α1 subunit of pyruvate dehydrogenase (PDH) in mitochondria. Treatment improved oxidative phosphorylation in 24-mo-old SSM and IFM at baseline compared with vehicle. When 4-PBA-treated 24-mo-old hearts were subjected to ischemia-reperfusion, infarct size was decreased. These results support that attenuation of the ER stress decreased cardiac injury in aged hearts by improving mitochondrial function before ischemia. To challenge the role of CPN1 as an effector of the ER stress, aged mice were treated with MDL-28170 (MDL, an inhibitor of calpain 1). MDL treatment improved mitochondrial function in aged SSM and IFM. MDL-treated 24-mo-old hearts sustained less cardiac injury following ischemia-reperfusion. These results support that age-induced ER stress augments cardiac injury during ischemia-reperfusion by impairing mitochondrial function through activation of CPN1.

The Effectiveness of CS Reducer for the treatment of Refractory Angina - a Meta-Analysis

BACKGROUND

Refractory angina is a debilitating condition that affects quality of life of patients worldwide, that after exhausting standard available therapies are regarded as "no option" patients. Recently, coronary sinus (CS) Reducer implantation became available and is gaining popularity in the treatment of refractory angina. The effectiveness of this therapy was demonstrated in one randomized sham-control trial and numerous uncontrolled prospective studies entailing altogether several hundred patients. We performed a meta-analysis to incorporate the data and elucidate its efficacy and safety.

METHODS

A meta-analysis of prospective studies assessing the effects of CS narrowing published in English until June 2021 was performed. The primary outcome was the proportion of patients improving ≥1 class in the Canadian Cardiovascular Society (CSS) angina score. Other endpoints included proportion of patients improving ≥2 CCS classes, procedural success, periprocedural complications, changes in Seattle Angina Questionnaire (SAQ) scores, and six-minute walk test (6MWT).

RESULTS

Data from 9 studies, including 846 patients was included. An improvement of ≥1 CSS class occurred in 76% [95% CI 73%- 80%] of patients. Improvement of ≥2 CSS classes was observed in 40% of patients (95% CI of 35-46%). Procedure success was 98%, with no major and 3% of non-major periprocedural complications. Post procedural SAQ scores and 6MWT distance were significantly improved.

CONCLUSIONS

In patients suffering from angina refractory to medical and interventional therapies, CS narrowing implantation improves symptoms and quality of life, with a low complication rate. These results are consistent in one randomized trial and in multiple prospective, uncontrolled studies.

Systematic review of current natural language processing methods and applications in cardiology

Natural language processing (NLP) is a set of automated methods to organise and evaluate the information contained in unstructured clinical notes, which are a rich source of real-world data from clinical care that may be used to improve outcomes and understanding of disease in cardiology. The purpose of this systematic review is to provide an understanding of NLP, review how it has been used to date within cardiology and illustrate the opportunities that this approach provides for both research and clinical care. We systematically searched six scholarly databases (ACM Digital Library, Arxiv, Embase, IEEE Explore, PubMed and Scopus) for studies published in 2015-2020 describing the development or application of NLP methods for clinical text focused on cardiac disease. Studies not published in English, lacking a description of NLP methods, non-cardiac focused and duplicates were excluded. Two independent reviewers extracted general study information, clinical details and NLP details and appraised quality using a checklist of quality indicators for NLP studies. We identified 37 studies developing and applying NLP in heart failure, imaging, coronary artery disease, electrophysiology, general cardiology and valvular heart disease. Most studies used NLP to identify patients with a specific diagnosis and extract disease severity using rule-based NLP methods. Some used NLP algorithms to predict clinical outcomes. A major limitation is the inability to aggregate findings across studies due to vastly different NLP methods, evaluation and reporting. This review reveals numerous opportunities for future NLP work in cardiology with more diverse patient samples, cardiac diseases, datasets, methods and applications.

Comparison of functional exercise capacity, quality of life and respiratory and peripheral muscle strength between patients with stable angina and healthy controls

Objective

We aimed to compare functional exercise capacity, respiratory and peripheral muscle strength, pulmonary function and quality of life between patients with stable angina and healthy controls.

Methods

We compared 33 patients with stable angina (55.21 ± 6.12 years old, Canada Class II–III, left ventricular ejection fraction: 61.92 ± 7.55) and 30 healthy controls (52.70 ± 4.22 years old). Functional capacity (6-minute walk test (6-MWT)), respiratory muscle strength (mouth pressure device), peripheral muscle strength (dynamometer), pulmonary function (spirometer) and quality of life (Short Form 36 (SF-36)) were evaluated.

Results

6-MWT distance (499.20 ± 51.91 m versus 633.05 ± 57.62 m), maximal inspiratory pressure (85.42 ± 20.52 cmH₂O versus 110.44 ± 32.95 cmH₂O), maximal expiratory pressure (83.33 ± 19.05 cmH₂O versus 147.96 ± 54.80 cmH₂O) and peripheral muscle strength, pulmonary function and SF-36 sub-scores were lower in the angina group versus the healthy controls, respectively.

Conclusion

Impaired peripheral and respiratory muscle strength, reduction in exercise capacity and quality of life are obvious in patients with stable angina. Therefore, these parameters should be considered in stable angina physiotherapy programmes to improve impairments.

Chronic metformin treatment decreases cardiac injury during ischemia-reperfusion by attenuating endoplasmic reticulum stress with improved mitochondrial function

Aging impairs mitochondrial function that leads to greater cardiac injury during ischemia and reperfusion. Cardiac endoplasm reticulum (ER) stress increases with age and contributes to mitochondrial dysfunction. Metformin is an anti-diabetic drug that protects cardiac mitochondria during acute ER stress. We hypothesized that metformin treatment would improve preexisting mitochondrial dysfunction in aged hearts by attenuating ER stress, followed by a decrease in cardiac injury during subsequent ischemia and reperfusion.

Male young (3 mo.) and aged mice (24 mo.) received metformin (300 mg/kg/day) dissolved in drinking water with sucrose (0.2 g/100 ml) as sweetener for two weeks versus sucrose vehicle alone. Cytosol, subsarcolemmal (SSM), and interfibrillar mitochondria (IFM) were isolated. In separate groups, cardioprotection was evaluated using ex vivo isolated heart perfusion with 25 min. global ischemia and 60 min. reperfusion. Infarct size was measured.

The contents of CHOP and cleaved ATF6 were decreased in metformin-treated 24 mo. mice compared to vehicle, supporting a decrease in ER stress. Metformin treatment improved OXPHOS in IFM in 24 mo. using a complex I substrate. Metformin treatment decreased infarct size following ischemia-reperfusion. Thus, metformin feeding decreased cardiac injury in aged mice during ischemia-reperfusion by improving pre-ischemic mitochondrial function via inhibition of ER stress.

Pro-inflammatory Mediators and Oxidative Stress: Therapeutic Markers for Recurrent Angina Pectoris after Coronary Artery Stenting in Elderly Patients

BACKGROUND

Pro-inflammatory mediators and oxidative stress are related to severity of angina pectoris in patients with coronary heart disease.

OBJECTIVE

We evaluated the effects of pro-inflammatory mediators and oxidative stress on recurrent angina pectoris after coronary artery stenting in elderly patients.

METHODS

We determined the expression levels of malondialdehyde (MDA), acrolein (ACR), tumour necrosis factor-α (TNF-α), toll-like receptor 4 (TLR4), superoxide dismutase 3 (SOD3), paraoxonase-1 (PON-1), stromal cell-derived factor-1α (SDF-1α) and endothelial progenitor cells (EPCs) in elderly patients with recurrent angina pectoris after coronary artery stenting.

RESULTS

Levels of MDA, ACR, TNF-α and TLR4 were significantly increased (p<0.001), and levels of SOD3, PON-1, SDF-1α and EPCs were significantly decreased (p<0.001) in the elderly patients with recurrent angina pectoris after coronary artery stenting. MDA, ACR, TNF-α and TLR4 as markers of oxidative stress and pro-inflammatory mediators may have suppressed SOD3, PON-1, SDF-1α and EPCs as markers of anti-oxidative stress/anti-inflammatory responses. Oxidative stress and pro-inflammatory mediators were important factors involved in recurrent angina pectoris of elderly patients after coronary artery stenting.

CONCLUSION

Oxidative stress and pro-inflammatory mediators could be considered as potential non-invasive prognostic, predictive and therapeutic biomarkers for stable recurrent angina and recurrent unstable angina in the elderly patients after coronary artery stenting.

Blood pressure variability in patients with angina and non-obstructive coronary artery disease

There is a real challenge in the management of ischemia with non-obstructive coronary artery disease. So, we need to study the mechanisms of persistent angina and non-obstructive coronary artery (ANOCA) patients. One of those possible mechanisms is blood pressure variability (BPV). We aimed to study the relation between BPV and angina in patients with non-obstructive coronary artery disease. Our study included 150 patients with chest pain and positive non-invasive stress test suggestive of myocardial ischemia and normal coronary angiography or non-obstructive coronary artery disease. We used an ambulatory blood pressure monitoring device. We found a positive correlation between BPV as measured by average real variability (ARV) as well as standard deviation (SD) parameters and the severity of anginal symptoms with P values for all parameters was 0.001 except day systolic SD P-value was 0.021. We performed a regression analysis for all statistically significant parameters. We found that 24H diastolic ARV, day diastolic ARV, night diastolic ARV, 24H diastolic SD, day diastolic SD, and night diastolic SD were independent predictors of the severity of angina with P-values (0.015, 0.007, 0.011, 0.037, 0.014, and 0.029), respectively. We concluded that short-term BPV represented by ARV and SD had a consistent association with angina in patients with non-obstructive coronary artery disease. The diastolic parameters of ARV and SD were independent predictors of the severity of angina with non-obstructive coronary artery disease.

Deafening Silence: The Lack of Structured Patient Symptoms in Clinical Documentation of Angina

See Article Owlia et al

Angina Severity, Mortality, and Healthcare Utilization Among Veterans With Stable Angina

Background

Canadian Cardiovascular Society (CCS) angina severity classification is associated with mortality, myocardial infarction, and coronary revascularization in clinical trial and registry data. The objective of this study was to determine associations between CCS class and all‐cause mortality and healthcare utilization, using natural language processing to extract CCS classifications from clinical notes.

Methods and Results

In this retrospective cohort study of veterans in the United States with stable angina from January 1, 2006, to December 31, 2013, natural language processing extracted CCS classifications. Veterans with a prior diagnosis of coronary artery disease were excluded. Outcomes included all‐cause mortality (primary), all‐cause and cardiovascular‐specific hospitalizations, coronary revascularization, and 1‐year healthcare costs. Of 299 577 veterans identified, 14 216 (4.7%) had ≥1 CCS classification extracted by natural language processing. The mean age was 66.6±9.8 years, 99% of participants were male, and 81% were white. During a median follow‐up of 3.4 years, all‐cause mortality rates were 4.58, 4.60, 6.22, and 6.83 per 100 person‐years for CCS classes I, II, III, and IV, respectively. Multivariable adjusted hazard ratios for all‐cause mortality comparing CCS II, III, and IV with those in class I were 1.05 (95% CI, 0.95–1.15), 1.33 (95% CI, 1.20–1.47), and 1.48 (95% CI, 1.25–1.76), respectively. The multivariable hazard ratio comparing CCS IV with CCS I was 1.20 (95% CI, 1.09–1.33) for all‐cause hospitalization, 1.25 (95% CI, 0.96–1.64) for acute coronary syndrome hospitalizations, 1.00 (95% CI, 0.80–1.26) for heart failure hospitalizations, 1.05 (95% CI, 0.88–1.25) for atrial fibrillation hospitalizations, 1.92 (95% CI, 1.40–2.64) for percutaneous coronary intervention, and 2.51 (95% CI, 1.99–3.16) for coronary artery bypass grafting surgery.

Conclusions

Natural language processing–extracted CCS classification was positively associated with all‐cause mortality and healthcare utilization, demonstrating the prognostic importance of anginal symptom assessment and documentation.

See Editorial Mehta and Bradley