Predictors of heart failure readmission and all-cause mortality in patients with acute heart failure

BACKGROUND

Predischarge risk stratification of patients with acute heart failure (AHF) could facilitate tailored treatment and follow-up, however, simple scores to predict short-term risk for HF readmission or death are lacking.

METHODS

We sought to develop a congestion-focused risk score using data from a prospective, two-center observational study in adults hospitalized for AHF. Laboratory data were collected on admission. Patients underwent physical examination, 4-zone, and in a subset 8-zone, lung ultrasound (LUS), and echocardiography at baseline. A second LUS was performed before discharge in a subset of patients. The primary endpoint was the composite of HF hospitalization or all-cause death.

RESULTS

Among 350 patients (median age 75 years, 43% women), 88 participants (25%) were hospitalized or died within 90 days after discharge. A stepwise Cox regression model selected four significant independent predictors of the composite outcome, and each was assigned points proportional to its regression coefficient: NT-proBNP ≥2000 pg/mL (admission) (3 points), systolic blood pressure < 120 mmHg (baseline) (2 points), left atrial volume index ≥60 mL/m2 (baseline) (1 point) and ≥ 9 B-lines on predischarge 4-zone LUS (3 points). This risk score provided adequate risk discrimination for the composite outcome (HR 1.48 per 1 point increase, 95% confidence interval: 1.32-1.67, p < 0.001, C-statistic: 0.70). In a subset of patients with 8-zone LUS data (n = 176), results were similar (C-statistic: 0.72).

CONCLUSIONS

A four-variable risk score integrating clinical, laboratory and ultrasound data may provide a simple approach for risk discrimination for 90-day adverse outcomes in patients with AHF if validated in future investigations.

Body mass index and cardiorenal outcomes in the EMPEROR-Preserved trial: Principal findings and meta-analysis with the DELIVER trial

AIMS

Both low and high body mass index (BMI) are associated with poor heart failure outcomes. Whether BMI modifies benefits of sodium-glucose cotransporter 2 inhibitors (SGLT2i) in heart failure with preserved ejection fraction (HFpEF) requires further investigation.

METHODS AND RESULTS

Using EMPEROR-Preserved data, the effects of empagliflozin versus placebo on the risks for the primary outcome (hospitalization for heart failure [HHF] or cardiovascular [CV] death), change in estimated glomerular filtration rate (eGFR) slopes, change in Kansas City Cardiomyopathy Questionnaire clinical summary score (KCCQ-CSS), and secondary outcomes across baseline BMI categories (<25 kg/m2, 25 to <30 kg/m2, 30 to <35 kg/m2, 35 to <40 kg/m2 and ≥40 kg/m2) were examined, and a meta-analysis conducted with DELIVER. Forty-five percent had a BMI of ≥30 kg/m2. For the primary outcome, there was a consistent treatment effect of empagliflozin versus placebo across the BMI categories with no formal interaction (p trend = 0.19) by BMI categories. There was also no difference in the effects on secondary outcomes including total HHF (p trend = 0.19), CV death (p trend = 0.20), or eGFR slope with slower declines with empagliflozin regardless of BMI (range 1.12-1.71 ml/min/1.73 m2 relative to placebo, p trend = 0.85 for interaction), though there was no overall impact on the composite renal endpoint. The difference in weight change between empagliflozin and placebo was -0.59, -1.48, -1.54, -0.87, and - 2.67 kg in the lowest to highest BMI categories (p trend = 0.016 for interaction). A meta-analysis of data from EMPEROR-Preserved and DELIVER showed a consistent effect of SGLT2i versus placebo across BMI categories for the outcome of HHF or CV death. There was a trend toward greater absolute KCCQ-CSS benefit at 32 weeks with empagliflozin at higher BMIs (p = 0.08).

CONCLUSIONS

Empagliflozin treatment resulted in broadly consistent cardiac effects across the range of BMI in patients with HFpEF. SGLT2i treatment yields benefit in patients with HFpEF regardless of baseline BMI.

Advances in Multi-Modality Imaging in Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is characterized by abnormal growth of the myocardium with myofilament disarray and myocardial hyper-contractility, leading to left ventricular hypertrophy and fibrosis. Where culprit genes are identified, they typically relate to cardiomyocyte sarcomere structure and function. Multi-modality imaging plays a crucial role in the diagnosis, monitoring, and risk stratification of HCM, as well as in screening those at risk. Following the recent publication of the first European Society of Cardiology (ESC) cardiomyopathy guidelines, we build on previous reviews and explore the roles of electrocardiography, echocardiography, cardiac magnetic resonance (CMR), cardiac computed tomography (CT), and nuclear imaging. We examine each modality's strengths along with their limitations in turn, and discuss how they can be used in isolation, or in combination, to facilitate a personalized approach to patient care, as well as providing key information and robust safety and efficacy evidence within new areas of research.

Appetite and its Regulation: Are there Palatable Interventions for Heart Failure?

PURPOSE OF REVIEW

Obesity is a major driver of heart failure (HF) incidence, and aggravates its pathophysiology. We summarized key reported and ongoing randomized clinical trials of appetite regulation and/or dietary energy restriction in individuals with HF.

RECENT FINDINGS

Weight loss can be achieved by structured supervised diet programs with behavioural change, medications, or surgery. The new glucagon-like peptide-1 receptor agonists alone or in combination with other agents (e.g., glucose-dependent insulinotropic polypeptide and glucagon receptor agonists or amylin analogues) potently and sustainably reduce appetite, and, taken together with dietary advice, can produce substantial, life-changing, weight loss approaching that achieved by surgery. To date, data from the STEP-HFpEF trial show meaningful improvements in health status (Kansas City Cardiomyopathy Questionnaire). Effective weight management could relieve several drivers of HF, to complement the existing treatments for HF with both reduced and preserved ejection fraction. Further trials of weight loss interventions will provide more definitive evidence to understand their effects on clinical events in patients with HF.

Effects of renin-angiotensin system blockers on outcomes from COVID-19: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND AND AIMS

Randomized controlled trials (RCTs) have assessed the effects of renin-angiotensin system (RAS) blockers in adults with coronavirus disease 2019 (COVID-19). This meta-analysis provides estimates of the safety and efficacy of treatment with (vs. without) RAS blockers from these trials.

METHODS

PubMed, Web of Science, and ClinicalTrials.gov were searched (1 March-12 April 2023). Event/patient numbers were extracted, comparing angiotensin-converting enzyme (ACE) inhibitor/angiotensin-receptor blocker (ARB) treatment with no treatment, for the outcomes: intensive care unit (ICU) admission, mechanical ventilation, vasopressor use, acute kidney injury (AKI), renal replacement therapy (RRT), acute myocardial infarction, stroke/transient ischaemic attack, heart failure, thromboembolic events, and all-cause death. Fixed-effects meta-analysis estimates were pooled.

RESULTS

Sixteen RCTs including 3492 patients were analysed. Compared with discontinuation of RAS blockers, continuation was not associated with increased risk of ICU [risk ratio (RR) 0.96, 0.66-1.41], ventilation (RR 0.77, 0.55-1.09), vasopressors (RR 0.92, 0.58-1.44), AKI (RR 1.01, 0.40-2.56), RRT (RR 1.01, 0.46-2.21), or thromboembolic events (RR 1.07, 0.36-3.19). RAS blocker initiation was not associated with increased risk of ICU (RR 0.71, 0.47-1.08), ventilation (RR 1.12, 0.91-1.38), AKI (RR 1.28, 0.89-1.86), RRT (RR 1.66, 0.89-3.12), or thromboembolic events (RR 1.20, 0.06-23.70), although vasopressor use increased (RR 1.27, 1.02-1.57). The RR for all-cause death in the continuation/discontinuation trials was 1.24 (0.80-1.92), and 1.22 (0.96-1.55) in the initiation trials. In patients with severe/critical COVID-19, RAS blocker initiation increased the risk of all-cause death (RR 1.31, 1.01-1.72).

CONCLUSION

ACE inhibitors and ARBs may be continued in non-severe COVID-19 infection, where indicated. Conversely, initiation of RAS blockers may be harmful in critically ill patients.PROSPERO registration number: CRD42023408926.

Exercise Capacity in Patients With Obstructive Hypertrophic Cardiomyopathy: SEQUOIA-HCM Baseline Characteristics and Study Design

Patients with obstructive hypertrophic cardiomyopathy (oHCM) have increased risk of arrhythmia, stroke, heart failure, and sudden death. Contemporary management of oHCM has decreased annual hospitalization and mortality rates, yet patients have worsening health-related quality of life due to impaired exercise capacity and persistent residual symptoms. Here we consider the design of clinical trials evaluating potential oHCM therapies in the context of SEQUOIA-HCM (Safety, Efficacy, and Quantitative Understanding of Obstruction Impact of Aficamten in HCM). This large, phase 3 trial is now fully enrolled (N = 282). Baseline characteristics reflect an ethnically diverse population with characteristics typical of patients encountered clinically with substantial functional and symptom burden. The study will assess the effect of aficamten vs placebo, in addition to standard-of-care medications, on functional capacity and symptoms over 24 weeks. Future clinical trials could model the approach in SEQUOIA-HCM to evaluate the effect of potential therapies on the burden of oHCM. (Safety, Efficacy, and Quantitative Understanding of Obstruction Impact of Aficamten in HCM [SEQUOIA-HCM]; NCT05186818).

Differentiating Cardiac Troponin Levels During Cardiac Myosin Inhibition or Cardiac Myosin Activation Treatments: Drug Effect or the Canary in the Coal Mine?

PURPOSE OF REVIEW

Cardiac myosin inhibitors (CMIs) and activators are emerging therapies for hypertrophic cardiomyopathy (HCM) and heart failure with reduced ejection fraction (HFrEF), respectively. However, their effects on cardiac troponin levels, a biomarker of myocardial injury, are incompletely understood.

RECENT FINDINGS

In patients with HCM, CMIs cause substantial reductions in cardiac troponin levels which are reversible after stopping treatment. In patients with HFrEF, cardiac myosin activator (omecamtiv mecarbil) therapy cause modest increases in cardiac troponin levels which are reversible following treatment cessation and not associated with myocardial ischaemia or infarction. Transient changes in cardiac troponin levels might reflect alterations in cardiac contractility and mechanical stress. Such transient changes might not indicate cardiac injury and do not appear to be associated with adverse outcomes in the short to intermediate term. Longitudinal changes in troponin levels vary depending on the population and treatment. Further research is needed to elucidate mechanisms underlying changes in troponin levels.

A case report of myocardial infarction in a young transgender man with testosterone therapy: raising awareness on healthcare issues in the transgender community and a call for further research

Background

People who are transgender may utilize masculinizing or feminizing gender-affirming hormonal therapy. Testosterone and oestrogen receptors are expressed throughout the cardiovascular system, yet the effects of these therapies on cardiovascular risk and outcomes are largely unknown. We report the case of a young transgender man with no discernible cardiovascular risk factors presenting with an acute coronary syndrome.

Case summary

A 31-year-old transgender man utilizing intramuscular testosterone masculinizing gender-affirming hormonal therapy presented with central chest pain radiating to the left arm. He had no past medical history of hypertension, dyslipidaemia, diabetes, or smoking. Electrocardiography demonstrated infero-septal ST depression, and high-sensitivity troponin-I was elevated and increased to 19 686 ng/L. He was diagnosed with a non-ST-segment elevation myocardial infarction. Inpatient coronary angiography confirmed a critical focal lesion in the mid right coronary artery, which was managed with two drug-eluting stents. Medical management (i.e. aspirin, ticagrelor, atorvastatin, ramipril, and bisoprolol) and surveillance of residual plaque disease evident in the long tubular left main stem, proximal left anterior descending, and proximal circumflex vessels was undertaken. The masculinizing gender-affirming hormonal therapy was continued.

Discussion

Despite a greater awareness of the potential risk of increased cardiovascular disease in transgender people, the fundamental lack of data regarding cardiovascular outcomes in transgender people may be contributing to healthcare inequalities in this population. We must implement better training, awareness, and research into transgender cardiovascular health to facilitate equitable and evidence-based outcomes.

Dapagliflozin vs. metolazone in heart failure resistant to loop diuretics

BACKGROUND AND AIMS

To examine the decongestive effect of the sodium-glucose cotransporter 2 inhibitor dapagliflozin compared to the thiazide-like diuretic metolazone in patients hospitalized for heart failure and resistant to treatment with intravenous furosemide.

METHODS AND RESULTS

A multi-centre, open-label, randomized, and active-comparator trial. Patients were randomized to dapagliflozin 10 mg once daily or metolazone 5-10 mg once daily for a 3-day treatment period, with follow-up for primary and secondary endpoints until day 5 (96 h). The primary endpoint was a diuretic effect, assessed by change in weight (kg). Secondary endpoints included a change in pulmonary congestion (lung ultrasound), loop diuretic efficiency (weight change per 40 mg of furosemide), and a volume assessment score. 61 patients were randomized. The mean (±standard deviation) cumulative dose of furosemide at 96 h was 977 (±492) mg in the dapagliflozin group and 704 (±428) mg in patients assigned to metolazone. The mean (±standard deviation) decrease in weight at 96 h was 3.0 (2.5) kg with dapagliflozin compared to 3.6 (2.0) kg with metolazone [mean difference 0.65, 95% confidence interval (CI) -0.12,1.41 kg; P = 0.11]. Loop diuretic efficiency was less with dapagliflozin than with metolazone [mean 0.15 (0.12) vs. 0.25 (0.19); difference -0.08, 95% CI -0.17,0.01 kg; P = 0.10]. Changes in pulmonary congestion and volume assessment score were similar between treatments. Decreases in plasma sodium and potassium and increases in urea and creatinine were smaller with dapagliflozin than with metolazone. Serious adverse events were similar between treatments.

CONCLUSION

In patients with heart failure and loop diuretic resistance, dapagliflozin was not more effective at relieving congestion than metolazone. Patients assigned to dapagliflozin received a larger cumulative dose of furosemide but experienced less biochemical upset than those assigned to metolazone.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04860011.

A review of current key guidelines for managing high risk patients with diabetes and heart failure and future prospects

AIMS

To review recent guidelines on management of heart failure (HF) in patients with diabetes.

MATERIALS AND METHODS

Major recommendations in European and USA society guidelines were scrutinised.

RESULTS

First, sodium-glucose co-transporter 2 inhibitors (SGLT2i) are now recommended treatments for all patients with symptomatic heart failure (stage C and D; New York Heart Association II-IV), irrespective of diabetes status and left ventricular ejection fraction (LVEF). Second, patients with HF and reduced ejection fraction (LVEF ≤40%) should have foundational therapies from four drug classes (SGLT2i, angiotensin-receptor neprilysin inhibitor (ARNI), beta-blocker and mineralocorticoid receptor antagonist (MRA)). Third, patients with HF with mildly reduced (41-49%) and preserved (≥50%) LVEF may also benefit from ARNI, beta-blocker and MRA therapy, although evidence for these is less robust. Fourth, selected patients should be considered for other therapies such as diuretics (if congestion), anticoagulation (if atrial fibrillation) and cardiac device therapy. Fifth, glucose-lowering therapies such as thiazolidinediones and certain dipeptidyl peptidase-4 inhibitors (such as saxagliptin and alogliptin) should be avoided in patients with heart failure. Sixth, guidelines recommend enrolment of patients with HF into exercise rehabilitation and multidisciplinary HF management programmes. Particular attention should be paid to important co-morbidities such as obesity, alongside pharmacological therapies.

CONCLUSIONS

As diabetes and obesity are major risk factors for HF, earlier consideration of, and diagnosis of HF, followed by guideline-directed medical therapy can meaningfully improve patients' lives. Diabetes doctors would do well to understand the basics of such guidelines to help improve all aspects of HF diagnosis and care. This article is protected by copyright. All rights reserved.

Health-related quality of life in acute heart failure: association between patient-reported symptoms and markers of congestion

AIMS

The aim of this study was to examine the association between patient-reported symptoms and the extent of pulmonary congestion in acute heart failure (AHF).

METHODS AND RESULTS

In this prospective, observational study, patient-reported symptoms were assessed at baseline using the Kansas City Cardiomyopathy Questionnaire total symptom score (KCCQ-TSS) (range 0-100; 0 worst) in patients hospitalized for AHF. In a subset, patient-reported dyspnoea at rest and on exertion was examined (range 0-10; 10 worst) at baseline. In addition, 4-zone lung ultrasound (LUS) was performed at baseline at the time of echocardiography. B-lines were quantified offline, blinded to clinical findings, by a core laboratory. Chest X-ray (CXR) and physical examination findings were collected from the medical records. Among 322 patients (mean age 72, 60% men, mean left ventricular ejection fraction 39%) with AHF, the median KCCQ-TSS score was 33 (interquartile range 18-48). Worse KCCQ-TSS was associated with worse New York Heart Association class, dyspnoea at rest and on exertion, and peripheral oedema (p trend <0.001 for all). However, KCCQ-TSS was not associated with the extent of pulmonary congestion, as assessed by the number of B-lines on LUS, or findings on CXR, or physical examination (p trend >0.25 for all). Similarly, KCCQ-TSS was not significantly associated with echocardiographic markers of left ventricular filling pressure, pulmonary pressure or with N-terminal pro-B-type natriuretic peptide level.

CONCLUSIONS

Among patients hospitalized for AHF, at baseline, KCCQ-TSS was not associated with pulmonary congestion assessed by LUS, CXR, or physical examination. These findings suggest that the profound reduction in KCCQ-TSS in patients with AHF may not be solely explained by pulmonary congestion.

Efficacy of implantable haemodynamic monitoring in heart failure across ranges of ejection fraction: a systematic review and meta-analysis

Aims

We conducted a meta-analysis of randomised controlled trials (RCTs) of implantable haemodynamic monitoring (IHM)-guided care.

Methods

PubMed and Ovid MEDLINE were searched for RCTs of IHM in patients with heart failure (HF). Outcomes were examined in total (first and recurrent) event analyses.

Results

Five trials comparing IHM-guided care with standard care alone were identified and included 2710 patients across ejection fraction (EF) ranges. Data were available for 628 patients (23.2%) with heart failure with preserved ejection fraction (HFpEF) (EF ≥50%) and 2023 patients (74.6%) with heart failure with a reduced ejection fraction (HFrEF) (EF <50%). Chronicle, CardioMEMS and HeartPOD IHMs were used. In all patients, regardless of EF, IHM-guided care reduced total HF hospitalisations (HR 0.74, 95% CI 0.66 to 0.82) and total worsening HF events (HR 0.74, 95% CI 0.66 to 0.84). In patients with HFrEF, IHM-guided care reduced total worsening HF events (HR 0.75, 95% CI 0.66 to 0.86). The effect of IHM-guided care on total worsening HF events in patients with HFpEF was uncertain (fixed-effect model: HR 0.72, 95% CI 0.59 to 0.88; random-effects model: HR 0.60, 95% CI 0.32 to 1.14). IHM-guided care did not reduce mortality (HR 0.92, 95% CI 0.71 to 1.20). IHM-guided care reduced all-cause mortality and total worsening HF events (HR 0.80, 95% CI 0.72 to 0.88).

Conclusions

In patients with HF across all EFs, IHM-guided care reduced total HF hospitalisations and worsening HF events. This benefit was consistent in patients with HFrEF but not consistent in HFpEF. Further trials with pre-specified analyses of patients with an EF of ≥50% are required.

PROSPERO registration number

CRD42021253905.

Cardiovascular and mortality outcomes with GLP-1 receptor agonists in patients with type 2 diabetes: A meta-analysis with the FREEDOM cardiovascular outcomes trial

BACKGROUND AND AIMS

FREEDOM, a cardiovascular outcome trial with a GLP-1 receptor agonist, testing a continuous subcutaneous infusion of exenatide (ITCA 650), recently reported its findings.

METHODS

We meta-analysed its results with eight prior GLP-1 receptor agonists trials.

RESULTS

GLP-1 receptor agonists reduced MACE by 13% (HR 0.87 [95% CI 0.81-0.94]; p = 0.00065) and all-cause mortality by 11% (HR 0.89 [0.83-0.95]; p = 0.00084). However, FREEDOM results appear dissimilar to prior GLP-1 receptor agonist trials.

CONCLUSION

FREEDOM results should not influence current considerations about the benefits or harms of approved formulations of GLP-1 receptor agonists. There is also an ongoing debate about the safety of ITCA 650.

Cardiovascular, mortality, and kidney outcomes with GLP-1 receptor agonists in patients with type 2 diabetes: a systematic review and meta-analysis of randomised trials

BACKGROUND

GLP-1 receptor agonists reduce major adverse cardiovascular events (MACE) in patients with type 2 diabetes. However, uncertainty regarding kidney outcomes persists and whether benefits extend to exendin-4-based GLP-1 receptor remains uncertain. We aimed to meta-analyse the most up-to-date evidence on the cardiovascular benefits and risks of GLP-1 receptor agonists from outcome trials in patients with type 2 diabetes.

METHODS

We did a meta-analysis, including new data from AMPLITUDE-O, using a random effects model to estimate overall hazard ratio (HR) for MACE; its components; all-cause mortality; hospital admission for heart failure; a composite kidney outcome consisting of development of macroalbuminuria, doubling of serum creatinine, or at least 40% decline in estimated glomerular filtration rate (eGFR), kidney replacement therapy, or death due to kidney disease; worsening of kidney function, based on eGFR change; and odds ratios for key safety outcomes (severe hypoglycaemia, retinopathy, pancreatitis, and pancreatic cancer). We also examined MACE outcome in patient subgroups on the basis of MACE incidence rates in the placebo group, presence or absence of cardiovascular disease, HbA_1c level, trial duration, treatment dosing interval, structural homology to human GLP-1 or exendin-4, BMI, age, and eGFR. We searched PubMed for eligible trials reporting MACE (ie, cardiovascular death, myocardial infarction, or stroke), up to June 9, 2021. We meta-analysed data from published randomised placebo-controlled trials testing either injectable or oral GLP-1 receptor agonists in patients with type 2 diabetes. We restricted the search to trials of more than 500 patients with a primary outcome that included cardiovascular death, non-fatal myocardial infarction, and non-fatal stroke. This meta-analysis was registered on PROSPERO, CRD42021259711.

FINDINGS

Of 98 articles screened, eight trials comprising 60 080 patients fulfilled the prespecified criteria and were included. Overall, GLP-1 receptor agonists reduced MACE by 14% (HR 0·86 [95% CI 0·80-0·93]; p<0·0001), with no significant heterogeneity across GLP-1 receptor agonist structural homology or eight other examined subgroups (all p_interaction≥0·14). GLP-1 receptor agonists reduced all-cause mortality by 12% (HR 0·88 [95% CI 0·82-0·94]; p=0·0001), hospital admission for heart failure by 11% (HR 0·89 [95% CI 0·82-0·98]; p=0·013), and the composite kidney outcome by 21% (HR 0·79 [95% CI 0·73-0·87]; p<0·0001), with no increase in risk of severe hypoglycaemia, retinopathy, or pancreatic adverse effects. In sensitivity analyses removing the only trial restricted to patients with an acute coronary syndrome (ELIXA), all benefits marginally increased, including the outcome of worsening of kidney function, based on eGFR change (HR 0·82 [95% CI 0·69-0·98]; p=0·030).

INTERPRETATION

GLP-1 receptor agonists, regardless of structural homology, reduced the risk of individual MACE components, all-cause mortality, hospital admission for heart failure, and worsening kidney function in patients with type 2 diabetes.

FUNDING

None.

Effect of Neprilysin Inhibition on Left Ventricular Remodeling in Patients With Asymptomatic Left Ventricular Systolic Dysfunction Late After Myocardial Infarction

BACKGROUND

Patients with left ventricular (LV) systolic dysfunction after myocardial infarction are at a high risk of developing heart failure. The addition of neprilysin inhibition to renin angiotensin system inhibition may result in greater attenuation of adverse LV remodeling as a result of increased levels of substrates for neprilysin with vasodilatory, antihypertrophic, antifibrotic, and sympatholytic effects.

METHODS

We performed a prospective, multicenter, randomized, double-blind, active-comparator trial comparing sacubitril/valsartan 97/103 mg twice daily with valsartan 160 mg twice daily in patients ≥3 months after myocardial infarction with a LV ejection fraction ≤40% who were taking a renin angiotensin system inhibitor (equivalent dose of ramipril ≥2.5 mg twice daily) and a β-blocker unless contraindicated or intolerant. Patients in New York Heart Association class ≥II or with signs and symptoms of heart failure were excluded. The primary outcome was change from baseline to 52 weeks in LV end-systolic volume index measured using cardiac magnetic resonance imaging. Secondary outcomes included other magnetic resonance imaging measurements of LV remodeling, change in NT-proBNP (N-terminal pro-B-type natriuretic peptide) and high-sensitivity cardiac troponin I, and a patient global assessment of change questionnaire.

RESULTS

From July 2018 to June 2019, we randomized 93 patients with the following characteristics: mean age, 60.7±10.4 years; median time from myocardial infarction, 3.6 years (interquartile range, 1.2-7.2); mean LV ejection fraction, 36.8%±7.1%; and median NT-proBNP, 230 pg/mL (interquartile range, 124-404). Sacubitril/valsartan, compared with valsartan, did not significantly reduce LV end-systolic volume index; adjusted between-group difference, -1.9 mL/m² (95% CI, -4.9 to 1.0); P=0.19. There were no significant between-group differences in NT-proBNP, high-sensitivity cardiac troponin I, LV end-diastolic volume index, left atrial volume index, LV ejection fraction, LV mass index, or patient global assessment of change.

CONCLUSIONS

In patients with asymptomatic LV systolic dysfunction late after myocardial infarction, treatment with sacubitril/valsartan did not have a significant reverse remodeling effect compared with valsartan. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03552575.

Meta-analyses of Results From Randomized Outcome Trials Comparing Cardiovascular Effects of SGLT2is and GLP-1RAs in Asian Versus White Patients With and Without Type 2 Diabetes

BACKGROUND

Results of cardiovascular outcome trials (CVOTs) suggest Asians may derive greater benefit than Whites from newer classes of antihyperglycemic medications.

PURPOSE

To provide summary hazard ratio (HR) estimates for cardiovascular efficacy of sodium-glucose cotransporter 2 inhibitors (SGLT2is) and glucagon-like peptide 1 receptor agonists (GLP-1RAs) stratified by race (Asian vs. White).

DATA SOURCES

A systematic review performed in PubMed from 1 January 2015 to 8 December 2020.

STUDY SELECTION

Randomized placebo-controlled CVOTs of SGLT2is and GLP-1RAs that reported HRs (95% CIs) for 1) major adverse cardiovascular event (MACE) in patients with diabetes and 2) cardiovascular (CV) death/hospitalization for heart failure (HHF) in patients with HF and reduced ejection fraction (HFrEF).

DATA EXTRACTION AND SYNTHESIS

HRs (95% CIs) for selected outcomes in Asians and Whites were extracted from each trial, adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Random-effects meta-analyses were performed to examine differences between the selected outcomes in Asians versus Whites.

RESULTS

In four SGLT2i trials in type 2 diabetes, the MACE outcome HR (95% CI) in 3,298 Asians versus 20,258 Whites was 0.81 (0.57, 1.04) vs. 0.90 (0.80, 1.00), respectively (P interaction = 0.46). In two SGLT2i trials in patients with HFrEF, the CV death/HHF outcome HR in 1,788 Asians versus 5,962 Whites was 0.60 (0.47, 0.74) vs. 0.82 (0.73, 0.92), respectively (P interaction = 0.01). In six GLP-1RA trials, the MACE outcome HR in 4,195 Asians versus 37,530 Whites was 0.68 (0.53, 0.84) vs. 0.87 (0.81, 0.94), respectively (P interaction = 0.03).

LIMITATIONS

Lack of individual patient-level data, relatively short duration of trial observation, and lack of granular categorization of race within broadly defined Asian subgroups.

CONCLUSIONS

Compared with Whites, Asians may derive greater CV death/HHF benefit from SGLT2is in patients with HFrEF, and MACE benefit from GLP-1RAs in patients with type 2 diabetes.

Renin-angiotensin system blockers, risk of SARS-CoV-2 infection and outcomes fromCoViD-19: systematic review and meta-analysis

Aims

This meta-analysis provides summary odds ratio (OR) estimates for associations between treatment with (vs. without) renin–angiotensin system blockers and risk of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection and coronavirus disease 2019 (CoViD-19) severity (including case-fatality) in patients with hypertension, and in all patients (irrespective of hypertension).

Methods and results

PubMed, EMBASE, Web of Science, Google Scholar, medRxiv, and SSRN were searched (2 May 2020 to 12 August 2020) for non-randomized observational CoViD-19 studies. Event/patient numbers were extracted, comparing angiotensin-converting enzyme (ACE) inhibitor/angiotensin-receptor blocker (ARB) treatment (and each separately), to treatment with neither drug, for the outcomes: (i) likelihood of SARS-CoV-2 infection; (ii) CoViD-19 severity [including hospitalization, intensive therapy unit (ITU), ventilation]; (iii) case-fatality. The risk of bias was assessed (ROBINS-I). Random-effects meta-analysis estimates were pooled. Eighty-six studies including 459 755 patients (103 317 with hypertension), were analysed. In patients with hypertension, ACE inhibitor or ARB treatment was not associated with a greater likelihood of SARS-CoV-2 infection in 60 141 patients (OR 1.06, 95% CI 0.99–1.14), hospitalization in 5925 patients (OR 0.90, 0.62–1.31), ITU in 7218 patients (OR 1.06, 0.73–1.56), ventilation (or ITU/ventilation/death) in 13 163 patients (OR 0.91, 0.72–1.15) or case-fatality in 18 735 patients with 2893 deaths (OR 0.75, 0.61–0.92).

Conclusion

Angiotensin-converting enzyme inhibitors and ARBs appear safe in the context of SARS-CoV-2 infection and should not be discontinued.

PROSPERO registration number CRD42020186996.

Effect of Empagliflozin on Left Ventricular Volumes in Patients With Type 2 Diabetes, or Prediabetes, and Heart Failure With Reduced Ejection Fraction (SUGAR-DM-HF)

BACKGROUND

Sodium-glucose cotransporter 2 inhibitors reduce the risk of heart failure hospitalization and cardiovascular death in patients with heart failure and reduced ejection fraction (HFrEF). However, their effects on cardiac structure and function in HFrEF are uncertain.

METHODS

We designed a multicenter, randomized, double-blind, placebo-controlled trial (the SUGAR-DM-HF trial [Studies of Empagliflozin and Its Cardiovascular, Renal and Metabolic Effects in Patients With Diabetes Mellitus, or Prediabetes, and Heart Failure]) to investigate the cardiac effects of empagliflozin in patients in New York Heart Association functional class II to IV with a left ventricular (LV) ejection fraction ≤40% and type 2 diabetes or prediabetes. Patients were randomly assigned 1:1 to empagliflozin 10 mg once daily or placebo, stratified by age (<65 and ≥65 years) and glycemic status (diabetes or prediabetes). The coprimary outcomes were change from baseline to 36 weeks in LV end-systolic volume indexed to body surface area and LV global longitudinal strain both measured using cardiovascular magnetic resonance. Secondary efficacy outcomes included other cardiovascular magnetic resonance measures (LV end-diastolic volume index, LV ejection fraction), diuretic intensification, symptoms (Kansas City Cardiomyopathy Questionnaire Total Symptom Score, 6-minute walk distance, B-lines on lung ultrasound, and biomarkers (including N-terminal pro-B-type natriuretic peptide).

RESULTS

From April 2018 to August 2019, 105 patients were randomly assigned: mean age 68.7 (SD, 11.1) years, 77 (73.3%) male, 82 (78.1%) diabetes and 23 (21.9%) prediabetes, mean LV ejection fraction 32.5% (9.8%), and 81 (77.1%) New York Heart Association II and 24 (22.9%) New York Heart Association III. Patients received standard treatment for HFrEF. In comparison with placebo, empagliflozin reduced LV end-systolic volume index by 6.0 (95% CI, -10.8 to -1.2) mL/m² (P=0.015). There was no difference in LV global longitudinal strain. Empagliflozin reduced LV end-diastolic volume index by 8.2 (95% CI, -13.7 to -2.6) mL/m² (P=0.0042) and reduced N-terminal pro-B-type natriuretic peptide by 28% (2%-47%), P=0.038. There were no between-group differences in other cardiovascular magnetic resonance measures, diuretic intensification, Kansas City Cardiomyopathy Questionnaire Total Symptom Score, 6-minute walk distance, or B-lines.

CONCLUSIONS

The sodium-glucose cotransporter 2 inhibitor empagliflozin reduced LV volumes in patients with HFrEF and type 2 diabetes or prediabetes. Favorable reverse LV remodeling may be a mechanism by which sodium-glucose cotransporter 2 inhibitors reduce heart failure hospitalization and mortality in HFrEF. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT03485092.

How Do SGLT2 (Sodium-Glucose Cotransporter 2) Inhibitors and GLP-1 (Glucagon-Like Peptide-1) Receptor Agonists Reduce Cardiovascular Outcomes?: Completed and Ongoing Mechanistic Trials

OBJECTIVE

There is substantial interest in how GLP-1RA (glucagon-like peptide-1 receptor agonists) and SGLT2 (sodium-glucose cotransporter 2) inhibitors reduce cardiovascular and renal events; yet, robust mechanistic data in humans remain sparse. We conducted a narrative review of published and ongoing mechanistic clinical trials investigating the actions of SGLT2 inhibitors and GLP-1RAs to help the community appreciate the extent of ongoing work and the variety and design of such trials. Approach and Results: To date, trials investigating the mechanisms of action of SGLT2 inhibitors have focused on pathways linked to glucose metabolism and toxicity, hemodynamic/volume, vascular and renal actions, and cardiac effects, including those on myocardial energetics. The participants studied have included those with established cardiovascular disease (including coronary artery disease and heart failure), liver disease, renal impairment, obesity, and hypertension; some of these trials have enrolled patients both with and without type 2 diabetes mellitus. GLP-1RA mechanistic trials have focused on glucose-lowering, insulin-sparing, weight reduction, and blood pressure-lowering effects, as well as possible direct vascular, cardiac, and renal effects of these agents. Very few mechanisms of action of SGLT2 inhibitors or GLP-1RAs have so far been convincingly demonstrated. One small trial (n=97) of SGLT2 inhibitors has investigated the cardiac effects of these drugs, where a small reduction in left ventricular mass was found. Data on vascular effects are limited to one trial in type 1 diabetes mellitus, which suggests some beneficial actions. SGLT2 inhibitors have been shown to reduce liver fat. We highlight the near absence of mechanistic data to explain the beneficial effects of SGLT2 inhibitors in patients without diabetes mellitus. GLP-1RAs have not been found to have major cardiovascular mechanisms of action in the limited, completed trials. Conflicting data around the impact on infarct size have been reported. No effect on left ventricular ejection fraction has been demonstrated.

CONCLUSIONS

We have tabulated the extensive ongoing mechanistic trials that will report over the coming years. We report 2 exemplar ongoing mechanistic trials in detail to give examples of the designs and techniques employed. The results of these many ongoing trials should help us understand how SGLT2 inhibitors and GLP-1RAs improve cardiovascular and renal outcomes and may also identify unexpected mechanisms suggesting novel therapeutic applications.

Comparing the interobserver reproducibility of different regions of interest on multi-parametric renal magnetic resonance imaging in healthy volunteers, patients with heart failure and renal transplant recipients

OBJECTIVE

To assess interobserver reproducibility of different regions of interest (ROIs) on multi-parametric renal MRI using commercially available software.

MATERIALS AND METHODS

Healthy volunteers (HV), patients with heart failure (HF) and renal transplant recipients (Tx) were recruited. Localiser scans, T1 mapping and pseudo-continuous arterial spin labelling (pCASL) were performed. HV and Tx also underwent diffusion-weighted imaging to allow calculation of apparent diffusion coefficient (ADC). For T1, pCASL and ADC, ROIs were drawn for whole kidney (WK), cortex (Cx), user-defined representative cortex (rep-Cx) and medulla. Intraclass correlation coefficient (ICC) and coefficient of variation (CoV) were assessed.

RESULTS

Forty participants were included (10 HV, 10 HF and 20 Tx). The ICC for renal volume was 0.97 and CoV 6.5%. For T1 and ADC, WK, Cx, and rep-Cx were highly reproducible with ICC ≥ 0.76 and CoV < 5%. However, cortical pCASL results were more variable (ICC > 0.86, but CoV up to 14.2%). While reproducible, WK values were derived from a wide spread of data (ROI standard deviation 17% to 55% of the mean value for ADC and pCASL, respectively). Renal volume differed between groups (p < 0.001), while mean cortical T1 values were greater in Tx compared to HV (p = 0.009) and HF (p = 0.02). Medullary T1 values were also higher in Tx than HV (p = 0.03), while medullary pCASL values were significantly lower in Tx compared to HV and HF (p = 0.03 for both).

DISCUSSION

Kidney volume calculated by manually contouring a localiser scan was highly reproducible between observers and detected significant differences across patient groups. For T1, pCASL and ADC, Cx and rep-Cx ROIs are generally reproducible with advantages over WK values.

Invasive Versus Medical Management in Patients With Prior Coronary Artery Bypass Surgery With a Non-ST Segment Elevation Acute Coronary Syndrome

Supplemental Digital Content is available in the text.

The benefits of routine invasive management in patients with prior coronary artery bypass grafts presenting with non-ST elevation acute coronary syndromes are uncertain because these patients were excluded from pivotal trials.

Statins in the Prevention and Treatment of Heart Failure: a Review of the Evidence

Purpose of Review

We summarize the best evidence for statins in the prevention and treatment of heart failure.

Recent Findings

In patients with cardiovascular risk factors or established atherosclerotic cardiovascular disease (but without heart failure), statins reduce the risk of incident heart failure—mainly by preventing myocardial infarction although an additional benefit from reducing myocardial ischemia cannot be excluded. However, in patients with established heart failure, statins do not reduce the risk of cardiovascular death, which is mainly caused by pump failure and ventricular arrhythmias. Retrospective analyses, however, suggest that statins may reduce the rate of heart failure hospitalization and atherosclerotic events (which are proportionately much less common in these patients than heart failure hospitalization or death).

Summary

Statin therapy should probably be continued in patients with coronary artery disease developing heart failure, although the weak evidence and small benefit may not justify the use of this treatment in very elderly patients with a short life expectancy and in which polypharmacy is a problem.

Prevalence of Prediabetes and Undiagnosed Diabetes in Patients with HFpEF and HFrEF and Associated Clinical Outcomes

PURPOSE

The prevalence and consequences of prediabetic dysglycemia and undiagnosed diabetes is unknown in patients with heart failure (HF) and preserved ejection fraction (HFpEF) and has not been compared to heart failure and reduced ejection fraction (HFrEF).

METHODS

We examined the prevalence and outcomes associated with normoglycemia, prediabetic dysglycemia and diabetes (diagnosed and undiagnosed) among individuals with a baseline glycated hemoglobin (hemoglobin A1c, HbA1c) measurement stratified by HFrEF or HFpEF in the Candesartan in Heart failure Assessment of Reduction in Mortality and morbidity programme (CHARM). We studied the primary outcome of HF hospitalization or cardiovascular (CV) death, and all-cause death, and estimated hazard ratios (HR) by use of multivariable Cox regression models.

RESULTS

HbA1c was measured at baseline in CHARM patients enrolled in the USA and Canada and was available in 1072/3023 (35%) of patients with HFpEF and 1578/4576 (34%) patients with HFrEF. 18 and 16% had normoglycemia (HbA1c < 6.0), 20 and 22% had prediabetes (HbA1c 6.0-6.4), respectively. Finally among patients with HFpEF 22% had undiagnosed diabetes (HbA1c > 6.4), and 40% had known diabetes (any HbA1c), with corresponding prevalence among HFrEF patients being 26 and 35%. The rates of both clinical outcomes of interest were higher in patients with undiagnosed diabetes and prediabetes, compared to normoglycemic patients, irrespective of HF subtype, and in general higher among HFrEF patients. For the primary composite outcome among HFpEF patients, the HRs were 1.02 (95% CI 0.63-1.65) for prediabetes, HR 1.18 (0.75-1.86) for undiagnosed diabetes and 2.75 (1.83-4.11) for known diabetes, respectively, p value for trend across groups < 0.001. Dysglycemia was also associated with worse outcomes in HFrEF.

CONCLUSIONS

These findings confirm the remarkably high prevalence of dysglycemia in heart failure irrespective of ejection fraction phenotype, and demonstrate that dysglycemia is associated with a higher risk of adverse clinical outcomes, even before the diagnosis of diabetes and institution of glucose lowering therapy in patients with HFpEF as well as HFrEF.

Microvascular complications in diabetes patients with heart failure and reduced ejection fraction-insights from the Beta-blocker Evaluation of Survival Trial

AIMS

The role of microvascular complications in the risk conferred by diabetes in heart failure with reduced ejection fraction (HFrEF) is unknown.

METHODS AND RESULTS

We studied 2707 HFrEF patients in the Beta-blocker Evaluation of Survival Trial (BEST), stratified into three groups: no diabetes and diabetes without or with microvascular complications (neuropathy, nephropathy, or retinopathy). The risks of the composite of cardiovascular death or heart failure hospitalization, and all-cause death, were studied using Cox regression analyses adjusted for other prognostic variables. Overall, 964 (36%) patients had diabetes, of which 313 (32%) had microvascular complications. Patients with microvascular complications had more severe symptoms (New York Heart Association class IV 12% vs. 9% diabetes with no complications and 7% no diabetes), and worse quality of life (Minnesota Living with Heart Failure median score 60 vs. 54 and 51 points). In patients with diabetes and complications, the rate of the composite outcome was 50 per 100 person-years of follow-up (compared with 34 and 29 in those with diabetes and no microvascular complications and participants without diabetes, respectively). Compared to patients without diabetes, the adjusted hazard ratio (HR) for the composite outcome was 1.44 [95% confidence interval (CI) 1.22-1.70] and 1.18 (95% CI 1.03-1.35) for patients with diabetes with and without complications, respectively. The risk of all-cause mortality was similarly elevated: adjusted HR 1.42 (95% CI 1.16-1.74) and 1.20 (95% CI 1.01-1.42), respectively.

CONCLUSION

In HFrEF, diabetes with microvascular complications is associated with worse symptoms and outcomes than diabetes without microvascular complications. Prevention of microvascular complications has the potential to improve HFrEF outcomes.

Diagnostic Accuracy of 3.0-T Magnetic Resonance T1 and T2 Mapping and T2-Weighted Dark-Blood Imaging for the Infarct-Related Coronary Artery in Non-ST-Segment Elevation Myocardial Infarction

BACKGROUND

Patients with recent non-ST-segment elevation myocardial infarction commonly have heterogeneous characteristics that may be challenging to assess clinically.

METHODS AND RESULTS

We prospectively studied the diagnostic accuracy of 2 novel (T1, T2 mapping) and 1 established (T2-weighted short tau inversion recovery [T2W-STIR]) magnetic resonance imaging methods for imaging the ischemic area at risk and myocardial salvage in 73 patients with non-ST-segment elevation myocardial infarction (mean age 57±10 years, 78% male) at 3.0-T magnetic resonance imaging within 6.5±3.5 days of invasive management. The infarct-related territory was identified independently using a combination of angiographic, ECG, and clinical findings. The presence and extent of infarction was assessed with late gadolinium enhancement imaging (gadobutrol, 0.1 mmol/kg). The extent of acutely injured myocardium was independently assessed with native T1, T2, and T2W-STIR methods. The mean infarct size was 5.9±8.0% of left ventricular mass. The infarct zone T1 and T2 times were 1323±68 and 57±5 ms, respectively. The diagnostic accuracies of T1 and T2 mapping for identification of the infarct-related artery were similar (P=0.125), and both were superior to T2W-STIR (P<0.001). The extent of myocardial injury (percentage of left ventricular volume) estimated with T1 (15.8±10.6%) and T2 maps (16.0±11.8%) was similar (P=0.838) and moderately well correlated (r=0.82, P<0.001). Mean extent of acute injury estimated with T2W-STIR (7.8±11.6%) was lower than that estimated with T1 (P<0.001) or T2 maps (P<0.001).

CONCLUSIONS

In patients with non-ST-segment elevation myocardial infarction, T1 and T2 magnetic resonance imaging mapping have higher diagnostic performance than T2W-STIR for identifying the infarct-related artery. Compared with conventional STIR, T1 and T2 maps have superior value to inform diagnosis and revascularization planning in non-ST-segment elevation myocardial infarction.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT02073422.

Non-invasive versus invasive management in patients with prior coronary artery bypass surgery with a non-ST segment elevation acute coronary syndrome: study design of the pilot randomised controlled trial and registry (CABG-ACS)

Introduction

There is an evidence gap about how to best treat patients with prior coronary artery bypass grafts (CABGs) presenting with non-ST segment elevation acute coronary syndromes (NSTE-ACS) because historically, these patients were excluded from pivotal randomised trials. We aim to undertake a pilot trial of routine non-invasive management versus routine invasive management in patients with NSTE-ACS with prior CABG and optimal medical therapy during routine clinical care. Our trial is a proof-of-concept study for feasibility, safety, potential efficacy and health economic modelling. We hypothesise that a routine invasive approach in patients with NSTE-ACS with prior CABG is not superior to a non-invasive approach with optimal medical therapy.

Methods and analysis

60 patients will be enrolled in a randomised clinical trial in 4 hospitals. A screening log will be prospectively completed. Patients not randomised due to lack of eligibility criteria and/or patient or physician preference and who give consent will be included in a registry. We will gather information about screening, enrolment, eligibility, randomisation, patient characteristics and adverse events (including post-discharge). The primary efficacy outcome is the composite of all-cause mortality, rehospitalisation for refractory ischaemia/angina, myocardial infarction and hospitalisation for heart failure. The primary safety outcome is the composite of bleeding, stroke, procedure-related myocardial infarction and worsening renal function. Health status will be assessed using EuroQol 5 Dimensions (EQ-5D) assessed at baseline and 6 monthly intervals, for at least 18 months.

Trial registration number

NCT01895751 (ClinicalTrials.gov).

Fractional flow reserve vs. angiography in guiding management to optimize outcomes in non-ST-segment elevation myocardial infarction: the British Heart Foundation FAMOUS-NSTEMI randomized trial

AIM

We assessed the management and outcomes of non-ST segment elevation myocardial infarction (NSTEMI) patients randomly assigned to fractional flow reserve (FFR)-guided management or angiography-guided standard care.

METHODS AND RESULTS

We conducted a prospective, multicentre, parallel group, 1 : 1 randomized, controlled trial in 350 NSTEMI patients with ≥1 coronary stenosis ≥30% of the lumen diameter assessed visually (threshold for FFR measurement) (NCT01764334). Enrolment took place in six UK hospitals from October 2011 to May 2013. Fractional flow reserve was disclosed to the operator in the FFR-guided group (n = 176). Fractional flow reserve was measured but not disclosed in the angiography-guided group (n = 174). Fractional flow reserve ≤0.80 was an indication for revascularization by percutaneous coronary intervention (PCI) or coronary artery bypass surgery (CABG). The median (IQR) time from the index episode of myocardial ischaemia to angiography was 3 (2, 5) days. For the primary outcome, the proportion of patients treated initially by medical therapy was higher in the FFR-guided group than in the angiography-guided group [40 (22.7%) vs. 23 (13.2%), difference 95% (95% CI: 1.4%, 17.7%), P = 0.022]. Fractional flow reserve disclosure resulted in a change in treatment between medical therapy, PCI or CABG in 38 (21.6%) patients. At 12 months, revascularization remained lower in the FFR-guided group [79.0 vs. 86.8%, difference 7.8% (-0.2%, 15.8%), P = 0.054]. There were no statistically significant differences in health outcomes and quality of life between the groups.

CONCLUSION

In NSTEMI patients, angiography-guided management was associated with higher rates of coronary revascularization compared with FFR-guided management. A larger trial is necessary to assess health outcomes and cost-effectiveness.

Reducing personal exposure to particulate air pollution improves cardiovascular health in patients with coronary heart disease

BACKGROUND

Air pollution exposure increases cardiovascular morbidity and mortality and is a major global public health concern.

OBJECTIVES

We investigated the benefits of reducing personal exposure to urban air pollution in patients with coronary heart disease.

METHODS

In an open randomized crossover trial, 98 patients with coronary heart disease walked on a predefined route in central Beijing, China, under different conditions: once while using a highly efficient face mask, and once while not using the mask. Symptoms, exercise, personal air pollution exposure, blood pressure, heart rate, and 12-lead electrocardiography were monitored throughout the 24-hr study period.

RESULTS

Ambient air pollutants were dominated by fine and ultrafine particulate matter (PM) that was present at high levels [74 μg/m³ for PM(2.5) (PM with aerodynamic diamater <2.5 µm)]. Consistent with traffic-derived sources, this PM contained organic carbon and polycyclic aromatic hydrocarbons and was highly oxidizing, generating large amounts of free radicals. The face mask was well tolerated, and its use was associated with decreased self-reported symptoms and reduced maximal ST segment depression (-142 vs. -156 μV, p = 0.046) over the 24-hr period. When the face mask was used during the prescribed walk, mean arterial pressure was lower (93 ± 10 vs. 96 ± 10 mmHg, p = 0.025) and heart rate variability increased (high-frequency power: 54 vs. 40 msec², p = 0.005; high-frequency normalized power: 23.5 vs. 20.5 msec, p = 0.001; root mean square successive differences: 16.7 vs. 14.8 msec, p = 0.007). However, mask use did not appear to influence heart rate or energy expenditure.

CONCLUSIONS

Reducing personal exposure to air pollution using a highly efficient face mask appeared to reduce symptoms and improve a range of cardiovascular health measures in patients with coronary heart disease. Such interventions to reduce personal exposure to PM air pollution have the potential to reduce the incidence of cardiovascular events in this highly susceptible population.