Heat and Cardiovascular Mortality: An Epidemiological Perspective.

As global temperatures rise, extreme heat events are projected to become more frequent and intense. Extreme heat causes a wide range of health effects, including an overall increase in morbidity and mortality. It is important to note that while there is sufficient epidemiological evidence for heat-related increases in all-cause mortality, evidence on the association between heat and cause-specific deaths such as cardiovascular disease (CVD) mortality (and its more specific causes) is limited, with inconsistent findings. Existing systematic reviews and meta-analyses of epidemiological studies on heat and CVD mortality have summarized the available evidence. However, the target audience of such reviews is mainly limited to the specific field of environmental epidemiology. This overarching perspective aims to provide health professionals with a comprehensive overview of recent epidemiological evidence of how extreme heat is associated with CVD mortality. The rationale behind this broad perspective is that a better understanding of the effect of extreme heat on CVD mortality will help CVD health professionals optimize their plans to adapt to the changes brought about by climate change and heat events. To policymakers, this perspective would help formulate targeted mitigation, strengthen early warning systems, and develop better adaptation strategies. Despite the heterogeneity in evidence worldwide, due in part to different climatic conditions and population dynamics, there is a clear link between heat and CVD mortality. The risk has often been found to be higher in vulnerable subgroups, including older people, people with preexisting conditions, and the socioeconomically deprived. This perspective also highlights the lack of evidence from low- and middle-income countries and focuses on cause-specific CVD deaths. In addition, the perspective highlights the temporal changes in heat-related CVD deaths as well as the interactive effect of heat with other environmental factors and the potential biological pathways. Importantly, these various aspects of epidemiological studies have never been fully investigated and, therefore, the true extent of the impact of heat on CVD deaths remains largely unknown. Furthermore, this perspective also highlights the research gaps in epidemiological studies and the potential solutions to generate more robust evidence on the future consequences of heat on CVD deaths.

Helicobacter pylori and Pro-Inflammatory Protein Biomarkers in Myocardial Infarction with and without Obstructive Coronary Artery Disease.

Myocardial infarction (MI) with obstructive coronary artery disease (MI-CAD) and MI in the absence of obstructive coronary artery disease (MINOCA) affect different populations and may have separate pathophysiological mechanisms, with greater inflammatory activity in MINOCA compared to MI-CAD. Helicobacter pylori (Hp) can cause systemic inflammation and has been associated with cardiovascular disease (CVD). We aimed to investigate whether Hp infection is associated with concentrations of protein biomarkers of inflammation and CVD. In a case-control study, patients with MINOCA (n = 99) in Sweden were included, complemented by matched subjects with MI-CAD (n = 99) and controls (n = 100). Protein biomarkers were measured with a proximity extension assay in plasma samples collected 3 months after MI. The seroprevalence of Hp and cytotoxin-associated gene A (CagA) was determined using ELISA. The associations between protein levels and Hp status were studied with linear regression. The prevalence of Hp was 20.2%, 19.2%, and 16.0% for MINOCA, MI-CAD, and controls, respectively (p = 0.73). Seven proteins were associated with Hp in an adjusted model: tissue plasminogen activator (tPA), interleukin-6 (IL-6), myeloperoxidase (MPO), TNF-related activation-induced cytokine (TRANCE), pappalysin-1 (PAPPA), soluble urokinase plasminogen activator receptor (suPAR), and P-selectin glycoprotein ligand 1 (PSGL-1). Hp infection was present in one in five patients with MI, irrespective of the presence of obstructive CAD. Inflammatory proteins were elevated in Hp-positive subjects, thus not ruling out that Hp may promote an inflammatory response and potentially contribute to the development of CVD.

Antiphospholipid antibodies in patients with myocardial infarction with and without obstructive coronary arteries.

BACKGROUND: Recent studies demonstrate that prothrombotic antiphospholipid antibodies (aPL) are overrepresented in patients with myocardial infarction (MI) due to coronary artery disease (MICAD). However, it is not known whether aPL differ between the two subsets of MI: MICAD and MI with nonobstructive coronary arteries (MINOCA). OBJECTIVES: To determine whether aPL are associated with MINOCA or MICAD, or with hypercoagulability as assessed by activated protein C-protein C inhibitor (APC-PCI) complex. METHODS: Well-characterized patients with MINOCA (n = 98), age- and gender-matched patients with MICAD (n = 99), and healthy controls (n = 100) were included in a cross-sectional case-control study. Autoantibodies (IgA/G/M) targeting cardiolipin and ß2 glycoprotein-I and specific nuclear antigens were analyzed by multiplexed bead technology. The concentration of APC-PCI was determined as a measure of hypercoagulability by an immunofluorometric sandwich assay. RESULTS: Both prevalence and titers of aPL of the IgG isotype (anti-cardiolipin and/or anti-ß2 glycoprotein-I) were higher in patients with MINOCA and MICAD than in controls. aPL IgG positivity was twice as frequent among patients with MICAD than MINOCA (11% vs. 6%, nonsignificant). We observed no group differences regarding aPL IgA/M or antibodies targeting specific nuclear antigens. Levels of APC-PCI were elevated in aPL IgG-positive compared to aPL IgG-negative MICAD patients. CONCLUSIONS: aPL IgG, but not IgA/M, are enriched particularly in patients with MICAD but also in patients with MINOCA, as compared to controls. Interestingly, signs of hypercoagulability-measured by increased levels of the APC-PCI complex-were present in aPL IgG-positive MICAD patients, indicating an association with functional disturbances of the coagulation system.

Randomized evaluation of beta blocker and ACE-inhibitor/angiotensin receptor blocker treatment in patients with myocardial infarction with non-obstructive coronary arteries (MINOCA-BAT): Rationale and design.

Myocardial infarction with non-obstructive coronary arteries (MINOCA) is common and occurs in 6-8% of all patients fulfilling the diagnostic criteria for acute myocardial infarction (AMI). This paper describes the rationale behind the trial 'Randomized Evaluation of Beta Blocker and ACE-Inhibitor/Angiotensin Receptor Blocker Treatment (ACEI/ARB) of MINOCA patients' (MINOCA-BAT) and the need to improve the secondary preventive treatment of MINOCA patients. METHODS: MINOCA-BAT is a registry-based, randomized, parallel, open-label, multicenter trial with 2:2 factorial design. The primary aim is to determine whether oral beta blockade compared with no oral beta blockade, and ACEI/ARB compared with no ACEI/ARB, reduce the composite endpoint of death of any cause, readmission because of AMI, ischemic stroke or heart failure in patients discharged after MINOCA without clinical signs of heart failure and with left ventricular ejection fraction ≥40%. A total of 3500 patients will be randomized into four groups; e.g. ACEI/ARB and beta blocker, beta blocker only, ACEI/ARB only and neither ACEI/ARB nor beta blocker, and followed for a mean of 4 years. SUMMARY: While patients with MINOCA have an increased risk of serious cardiovascular events and death, whether conventional secondary preventive therapies are beneficial has not been assessed in randomized trials. There is a limited basis for guideline recommendations in MINOCA. Furthermore, studies of routine clinical practice suggest that use of secondary prevention therapies in MINOCA varies considerably. Thus results from this trial may influence future treatment strategies and guidelines specific to MINOCA patients.

Comparative efficacy of sodium-glucose cotransporter-2 inhibitors (SGLT2i) for cardiovascular outcomes in type 2 diabetes: a systematic review and network meta-analysis of randomised controlled trials.

Sodium-glucose cotransporter-2 inhibitors (SGLT2i) improve cardiovascular outcomes in patients with type 2 diabetes mellitus (T2D). The comparative efficacy of individual SGLT2i remains unclear. We searched PubMed, www.clinicaltrials.gov and the Cochrane Central Register of Controlled Trials for randomised controlled trials exploring the use of canagliflozin, dapagliflozin, empagliflozin or ertugliflozin in patients with T2D. Comparators included placebo or any other active treatment. The primary endpoint was all-cause mortality. Secondary endpoints were cardiovascular mortality and worsening heart failure (HF). Evidence was synthesised using network meta-analysis (NMA). Sixty-four trials reporting on 74,874 patients were included. The overall quality of evidence was high. When compared with placebo, empagliflozin and canagliflozin improved all three endpoints, whereas dapagliflozin improved worsening HF. When compared with other SGLT2i, empagliflozin was superior for all-cause and cardiovascular mortality reduction. Empagliflozin, canagliflozin and dapagliflozin had similar effects on improving worsening HF. Ertugliflozin had no effect on any of the three endpoints investigated. Sensitivity analyses including extension periods of trials or excluding studies with a treatment duration of < 52 weeks confirmed the main results. Similar results were obtained when restricting mortality analyses to patients included in cardiovascular outcome trials (n = 38,719). Empagliflozin and canagliflozin improved survival with empagliflozin being superior to the other SGLT2i. Empagliflozin, canagliflozin and dapagliflozin had similar effects on improving worsening HF. Prospective head-to-head comparisons would be needed to confirm these results.

Contemporary Diagnosis and Management of Patients With Myocardial Infarction in the Absence of Obstructive Coronary Artery Disease: A Scientific Statement From the American Heart Association.

Myocardial infarction in the absence of obstructive coronary artery disease is found in ≈5% to 6% of all patients with acute infarction who are referred for coronary angiography. There are a variety of causes that can result in this clinical condition. As such, it is important that patients are appropriately diagnosed and an evaluation to uncover the correct cause is performed so that, when possible, specific therapies to treat the underlying cause can be prescribed. This statement provides a formal and updated definition for the broadly labelled term MINOCA (incorporating the definition of acute myocardial infarction from the newly released "Fourth Universal Definition of Myocardial Infarction") and provides a clinically useful framework and algorithms for the diagnostic evaluation and management of patients with myocardial infarction in the absence of obstructive coronary artery disease.

The Prospective Studies of Atherosclerosis (Proof-ATHERO) Consortium: Design and Rationale.

Atherosclerosis - the pathophysiological mechanism shared by most cardiovascular diseases - can be directly or indirectly assessed by a variety of clinical tests including measurement of carotid intima-media thickness, carotid plaque, -ankle-brachial index, pulse wave velocity, and coronary -artery calcium. The Prospective Studies of Atherosclerosis -(Proof-ATHERO) consortium (https://clinicalepi.i-med.ac.at/research/proof-athero/) collates de-identified individual-participant data of studies with information on atherosclerosis measures, risk factors for cardiovascular disease, and incidence of cardiovascular diseases. It currently comprises 74 studies that involve 106,846 participants from 25 countries and over 40 cities. In summary, 21 studies recruited participants from the general population (n = 67,784), 16 from high-risk populations (n = 22,677), and 37 as part of clinical trials (n = 16,385). Baseline years of contributing studies range from April 1980 to July 2014; the latest follow-up was until June 2019. Mean age at baseline was 59 years (standard deviation: 10) and 50% were female. Over a total of 830,619 person-years of follow-up, 17,270 incident cardiovascular events (including coronary heart disease and stroke) and 13,270 deaths were recorded, corresponding to cumulative incidences of 2.1% and 1.6% per annum, respectively. The consortium is coordinated by the Clinical Epidemiology Team at the Medical University of Innsbruck, Austria. Contributing studies undergo a detailed data cleaning and harmonisation procedure before being incorporated in the Proof-ATHERO central database. Statistical analyses are being conducted according to pre-defined analysis plans and use established methods for individual-participant data meta-analysis. Capitalising on its large sample size, the multi-institutional collaborative Proof-ATHERO consortium aims to better characterise, understand, and predict the development of atherosclerosis and its clinical consequences.

Left ventricular ejection fraction and adjudicated, cause-specific hospitalizations after myocardial infarction complicated by heart failure or left ventricular dysfunction.

BACKGROUND: Reduced left ventricular ejection fraction (LVEF) after acute myocardial infarction (MI) increases risk of cardiovascular (CV) hospitalizations, but evidence regarding its association with non-CV outcome is scarce. We investigated the association between LVEF and adjudicated cause-specific hospitalizations following MI complicated with low LVEF or overt heart failure (HF). METHODS: In an individual patient data meta-analysis of 19,740 patients from 3 large randomized trials, Fine and Gray competing risk modeling was performed to study the association between LVEF and hospitalization types. RESULTS: The most common cause of hospitalization was non-CV (n = 2,368 for HF, n = 1,554 for MI, and n = 3,703 for non-CV). All types of hospitalizations significantly increased with decreasing LVEF. The absolute risk increase associated with LVEF ≪25% (vs LVEF ≫35%) was 15.5% (95% CI 13.4-17.5) for HF, 4.7% (95% CI 3.0-6.4) for MI, and 10.4% (95% CI 8.0-12.8) for non-CV hospitalization. On a relative scale, after adjusting for confounders, each 5-point decrease in LVEF was associated with an increased risk of HF (hazard ratio [HR] 1.15, 95% CI 1.12-1.18), MI (HR 1.06, 95% CI 1.03-1.10), and non-CV hospitalization (HR 1.03, 95% CI 1.01-1.05). CONCLUSIONS: In a high-risk population with complicated acute MI, the absolute risk increase in non-CV hospitalizations associated with LVEF ≪25% was two thirds of the absolute risk increase in HF hospitalizations and twice the absolute risk increase in MI hospitalizations. LVEF was an independent predictor of all types of hospitalization and appears as an integrative marker of sicker patient status.

Increased Inflammatory Activity in Patients 3 Months after Myocardial Infarction with Nonobstructive Coronary Arteries.

BACKGROUND: Around 5%-10% of patients with myocardial infarction (MI) present with nonobstructive coronary arteries (MINOCA). We aimed to assess pathophysiological mechanisms in MINOCA by extensively evaluating cardiovascular biomarkers in the stable phase after an event, comparing MINOCA patients with cardiovascular healthy controls and MI patients with obstructive coronary artery disease (MI-CAD). METHODS: Ninety-one biomarkers were measured with a proximity extension assay 3 months after MI in 97 MINOCA patients, 97 age- and sex-matched MI-CAD patients, and 98 controls. Lasso analyses (penalized logistic regression models) and adjusted multiple linear regression models were used for statistical analyses. RESULTS: In the Lasso analysis (MINOCA vs MI-CAD), 8 biomarkers provided discriminatory value: P-selectin glycoprotein ligand 1, C-X-C motif chemokine 1, TNF-related activation-induced cytokine, and pappalysin-1 (PAPPA) with increasing probabilities of MINOCA, and tissue-type plasminogen activator, B-type natriuretic peptide, myeloperoxidase, and interleukin-1 receptor antagonist protein with increasing probabilities of MI-CAD. Comparing MINOCA vs controls, 7 biomarkers provided discriminatory value: N-terminal pro-B-type natriuretic peptide, renin, NF-κ-B essential modulator, PAPPA, interleukin-6, and soluble urokinase plasminogen activator surface receptor with increasing probabilities of MINOCA, and agouti-related protein with increasing probabilities of controls. Adjusted multiple linear regression analyses showed that group affiliation was associated with the concentrations of 7 of the 8 biomarkers in the comparison MINOCA vs MI-CAD and 5 of the 7 biomarkers in MINOCA vs controls. CONCLUSIONS: Three months after the MI, the biomarker concentrations indicated greater inflammatory activity in MINOCA patients than in both MI-CAD patients and healthy controls, and a varying degree of myocardial dysfunction among the 3 cohorts.

All-Cause Mortality and Cardiovascular Outcomes With Non-Vitamin K Oral Anticoagulants Versus Warfarin in Patients With Heart Failure in the Food and Drug Administration Adverse Event Reporting System.

BACKGROUND: Many patients with heart failure (HF) are treated with warfarin or non-vitamin K oral anticoagulants (NOACs). Randomized outcome-driven comparisons of different anticoagulant strategies in HF are lacking. Data from international, government-mandated registries may be useful in understanding the real-life use of various anticoagulants and how they are linked to outcomes. STUDY QUESTION: To assess 2015 annual all-cause mortality, myocardial infarction, and stroke rates co-reported for warfarin and NOACs in subjects with and without HF in the US Food and Drug Administration Adverse Event Reporting System (FAERS) database. STUDY DESIGN: We extracted and examined outcome cases in subjects with HF and on warfarin, dabigatran, rivaroxaban, apixaban, or edoxaban and stratified these according to anticoagulants. MEASURES AND OUTCOMES: Annual all-cause mortality, myocardial infarction, and stroke in FAERS. ANALYSIS METHOD: Odds ratio (OR) and χ(Equation is included in full-text article.)for oral anticoagulants from FAERS with and without HF among complete primary reports issued in 2015. RESULTS: FAERS reported 137,026 HF cases, with death co-reported in 42,942 (31.3%). In total, 11,278 (8.2%) HF patients were treated with anticoagulants, with more prescribed warfarin (n = 8260) than all NOACs combined (n = 3018). Very few reports for edoxaban were available. Warfarin consistently displayed a signal for excess adverse events compared to NOACs: OR (95% confidence interval) for the composite of mortality, myocardial infarction, and stroke were 1.91 (1.76-2.07) versus apixaban, 1.92 (1.81-2.03) versus dabigatran, 4.09 (3.38-4.37) versus rivaroxaban, and 2.64 (2.53-2.76) versus all NOACs combined (all P < 0.001). Warfarin, compared to all NOACs combined, demonstrated higher rates of all-cause mortality [OR = 2.69 (95% confidence interval, 2.49-2.90)], myocardial infarction [5.30 (4.17-6.74)], stroke [OR = 8.85 (6.61-11.84)], and ischemic stroke [OR = 12.73 (8.87-18.27); all P < 0.001]. CONCLUSIONS: Annual 2015 FAERS profiles in HF patients reveal that warfarin was numerically dominant. Warfarin was associated with higher risk of death, myocardial infarction, and stroke compared to NOACs. These observational data provide real-world insight into a potential safety benefit of NOACs over warfarin in the setting of HF.

Pharmacology of new treatments for hyperkalaemia: patiromer and sodium zirconium cyclosilicate.

Hyperkalaemia is a life-threatening condition, resulting from decreased renal function or dysfunctional homoeostatic mechanisms, often affecting patients with cardiovascular (CV) disease. Drugs such as renin-angiotensin-aldosterone system inhibitors (RAASi) are known to improve outcomes in CV patients but can also cause drug-induced hyperkalaemia. New therapeutic options exist to enhance potassium excretion in these patients. To this aim, we reviewed pharmacological properties and available data on patiromer and sodium zirconium cyclosilicate for the treatment of hyperkalaemia. These agents have been shown in randomized trials to significantly reduce serum potassium in patients with hyperkalaemia on renin-angiotensin-aldosterone system inhibitors. Additional research should focus on their long-term effects/safety profiles and drug-drug interactions.

Automatic identification of variables in epidemiological datasets using logic regression.

BACKGROUND: For an individual participant data (IPD) meta-analysis, multiple datasets must be transformed in a consistent format, e.g. using uniform variable names. When large numbers of datasets have to be processed, this can be a time-consuming and error-prone task. Automated or semi-automated identification of variables can help to reduce the workload and improve the data quality. For semi-automation high sensitivity in the recognition of matching variables is particularly important, because it allows creating software which for a target variable presents a choice of source variables, from which a user can choose the matching one, with only low risk of having missed a correct source variable. METHODS: For each variable in a set of target variables, a number of simple rules were manually created. With logic regression, an optimal Boolean combination of these rules was searched for every target variable, using a random subset of a large database of epidemiological and clinical cohort data (construction subset). In a second subset of this database (validation subset), this optimal combination rules were validated. RESULTS: In the construction sample, 41 target variables were allocated on average with a positive predictive value (PPV) of 34%, and a negative predictive value (NPV) of 95%. In the validation sample, PPV was 33%, whereas NPV remained at 94%. In the construction sample, PPV was 50% or less in 63% of all variables, in the validation sample in 71% of all variables. CONCLUSIONS: We demonstrated that the application of logic regression in a complex data management task in large epidemiological IPD meta-analyses is feasible. However, the performance of the algorithm is poor, which may require backup strategies.

Effects of Proprotein Convertase Subtilisin/Kexin Type 9 Antibodies in Adults With Hypercholesterolemia: A Systematic Review and Meta-analysis.

BACKGROUND: Guidelines recommend statins as first-line therapy for dyslipidemia. Monoclonal antibodies targeting proprotein convertase subtilisin/kexin type 9 (PCSK9) is a new lipid-lowering approach. PURPOSE: To assess the efficacy and safety of PCSK9 antibodies in adults with hypercholesterolemia. DATA SOURCES: MEDLINE, PubMed Central, and Google Scholar; conference proceedings; and the ClinicalTrials.gov registry through 4 April 2015. STUDY SELECTION: Phase 2 or 3 randomized, controlled trials (RCTs) comparing treatment using PCSK9 antibodies with no anti-PCSK9 therapy in adults with hypercholesterolemia. DATA EXTRACTION: Two investigators independently extracted data on study characteristics and lipid and clinical outcomes, and rated risk of bias of trials. Prespecified primary end points were all-cause and cardiovascular mortality. DATA SYNTHESIS: Twenty-four RCTs comprising 10 159 patients were included. Compared with no antibody, treatment with PCSK9 antibodies led to marked reductions in low-density lipoprotein cholesterol levels (mean difference, -47.49% [95% CI, -69.64% to -25.35%]; P < 0.001] and other atherogenic lipid fractions, and it reduced all-cause mortality (odds ratio [OR], 0.45 [CI, 0.23 to 0.86]; P = 0.015; heterogeneity P = 0.63; I2 = 0%) and cardiovascular mortality (OR, 0.50 [CI, 0.23 to 1.10]; P = 0.084; heterogeneity P = 0.78; I2 = 0%). The rate of myocardial infarction was significantly reduced with use of PCSK9 antibodies (OR, 0.49 [CI, 0.26 to 0.93]; P = 0.030; heterogeneity P = 0.45; I2 = 0%), and increases in the serum creatine kinase level were reduced (OR, 0.72 [CI, 0.54 to 0.96]; P = 0.026; heterogeneity P = 0.65; I2 = 0%). Serious adverse events did not increase with administration of PCSK9 antibodies. LIMITATION: Results were derived from study-level data rather than patient-level data, and clinical outcome data are rare. CONCLUSION: PCSK9 antibodies seem to be safe and effective for adults with dyslipidemia. PRIMARY FUNDING SOURCE: CRC 1116 Masterswitches in Myocardial Ischemia, German Research Council DFG.

Cardiac troponin I for prediction of clinical outcomes and cardiac function through 3-month follow-up after primary percutaneous coronary intervention for ST-segment elevation myocardial infarction.

BACKGROUND: Circulating levels of cardiac troponin I (cTnI) after ST-segment elevation myocardial infarction (STEMI) are associated with infarct size and chronic left ventricular dysfunction, but the relation to clinical end points and biochemical measures of global cardiac function remains less well defined. METHODS: One thousand sixty-six patients receiving primary percutaneous coronary intervention (PCI) in the PROTECTION AMI trial were studied in a post hoc analysis. Cardiac troponin I was measured at several time points during the index hospitalization, and patients were followed up for 3 months before reassessment including N-terminal pro-B-type natriuretic peptide (NT-proBNP) and left ventricular ejection fraction (LVEF) measurements. RESULTS: The median (quartile 1-3) cTnI levels were 0.4 (0.1-0.4) µg/L at admission, 33.1 (12.8-72.1) µg/L after 16 to 24 hours, and 9.1 (3.9-17.5) µg/L after 70 to 80 hours. In adjusted models, all post-PCI single points, peak, and area under curve were found to be independently associated with clinical events, NT-proBNP >118 pmol/L, or LVEF <40% (P for all <.001). When cTnI was added to a baseline risk model for prediction of clinical events, the C statistic improved from 0.779 to 0.846 (16-24 hours) and 0.859 (70-80 hours). Quantified by integrated discrimination improvement, the addition of cTnI significantly augmented prediction ability (relative integrated discrimination improvement 44%-154%; P for all ≤.001). Consistent improvements in discrimination of NT-proBNP >118 pmol/L and LVEF <40% were observed. CONCLUSIONS: Cardiac troponin I measured after primary PCI for STEMI is independently associated with clinical outcomes and cardiac function through 3-month follow-up. These results suggest that cTnI levels are a useful risk stratification tool in STEMI patients.