Cardiologist Perceptions on Automated Alerts and Messages To Improve Heart Failure Care.

Electronic health record (EHR)-embedded tools are known to improve prescribing of guideline-directed medical therapy (GDMT) for patients with heart failure. However, physicians may perceive EHR tools to be unhelpful, and may be therefore hesitant to implement these in their practice. We surveyed cardiologists about two effective EHR-tools to improve heart failure care, and they perceived the EHR tools to be easy to use, helpful, and improve the overall management of their patients with heart failure.

Electrocardiographic correlates of cardiac magnetic resonance findings in women with myocardial infarction with non-obstructive coronary arteries.

BACKGROUND: Myocardial infarction with nonobstructive coronary arteries (MINOCA) occurs in 6-15 % of MI patients. Cardiac magnetic resonance (CMR) imaging identifies MINOCA etiologies, but access may be limited. METHODS: We assessed associations between the index electrocardiogram (ECG) and CMR in MINOCA. Women with MI and < 50 % angiographic stenosis in all vessels were prospectively enrolled at 16 sites. CMR (median 6d from MI) was analyzed for late gadolinium enhancement (LGE), myocardial edema, and wall motion. We assessed ECGs for T-wave inversions (TWI), Q-waves (QW), ST-elevations (STE), ST-depressions (STD), and fragmented QRS complexes (fQRS). We calculated the DETERMINE score (# leads TWI + # fQRS +2*[# QW], excluding aVR, V1). RESULTS: Among 112 women with interpretable ECG, 81.3 % (91/112) had abnormal ECG; 50 % (56/112) had ≥1 TWI. CMR was abnormal in 74.1 % (83/112), with LGE in 49.1 % (55/112) and myocardial edema in 61.6 % (69/112). DETERMINE score ≥ 3 was associated with abnormal CMR (adjusted odds ratio [aOR] aOR 6.06 [1.89, 24.6], p = 0.002) and LGE (aOR 3.10 [1.26, 8.00], p = 0.013), but not edema (aOR 1.86 [0.80, 4.43], p = 0.152). TWI was also associated with abnormal CMR and LGE after adjustment (aOR 3.13 [1.08, 10.1], p = 0.036, aOR 3.23 [1.27, 8.63], p = 0.013, respectively), but not edema (aOR 1.26 [0.54, 2.96], p = 0.589). Specificity for abnormal CMR was 0.83 for DETERMINE score ≥ 3 and 0.75 for TWI. No other ECG findings were associated with CMR abnormality. CONCLUSION: DETERMINE score ≥ 3 and the presence of any TWI were associated with abnormal CMR and with LGE in MINOCA. Our findings demonstrate that the index ECG can provide insight on CMR findings but without sensitivity or specificity required to forgo the CMR. We reaffirm the central role of CMR in elucidating MINOCA pathophysiology.

Outcomes with revascularisation versus conservative management of participants with 3-vessel coronary artery disease in the ISCHEMIA trial.

BACKGROUND: Whether revascularisation (REV) improves outcomes in patients with three-vessel coronary artery disease (3V-CAD) is uncertain. AIMS: Our objective was to evaluate outcomes with REV (percutaneous coronary intervention [PCI] or coronary artery bypass graft surgery [CABG]) versus medical therapy in patients with 3V-CAD. METHODS: ISCHEMIA participants with 3V-CAD on coronary computed tomography angiography without prior CABG were included. Outcomes following initial invasive management (INV) with REV (PCI or CABG) versus initial conservative management (CON) with medical therapy alone were evaluated. Regression modelling was used to estimate the outcomes if all participants were to undergo prompt REV versus those assigned to CON. Outcomes were cardiovascular (CV) death/myocardial infarction (MI), death, CV death, and quality of life. Bayesian posterior probability for benefit (Pr [benefit]) for 1 percentage point lower 4-year rates with REV versus CON were evaluated. RESULTS: Among 1,236 participants with 3V-CAD (612 INV/624 CON), REV was associated with lower 4-year CV death/MI (adjusted 4-year difference: -4.4, 95% credible interval [CrI] -8.7 to -0.3 percentage points, Pr [benefit]=94.8%) when compared with CON, with similar results for PCI versus CON (-5.8, 95% CrI: -10.8 to -0.5 percentage points, Pr [benefit]=96.4%) and CABG versus CON (-3.7, 95% CrI: -8.8 to 1.5 percentage points, Pr [benefit]=84.7%). Adjusted 4-year REV versus CON differences were as follows: death -1.2 (95% CrI: -4.7 to 2.2) percentage points, CV death -2.3 (95% CrI: -5.5 to 0.8) percentage points, with similar results for PCI and for CABG. The Pr (benefit) for death with REV (PCI or CABG) versus CON was 49-63%. The adjusted 12-month Seattle Angina Questionnaire-7 summary score differences favoured REV: REV versus CON 4.6 (95% CrI: 2.7-6.4) percentage points; PCI versus CON 3.6 (95% CrI: 1.2-5.8) percentage points and CABG versus CON 4.3 (95% CrI: 1.5-6.9) percentage points with high Pr (benefit). CONCLUSIONS: In participants with 3V-CAD, REV (either PCI or CABG) was associated with a lower 4-year CV death/MI rate and improved quality of life, with similar results for PCI versus CON and CABG versus CON. The differences in all-cause mortality between REV and CON were small with wide confidence intervals. (ClinicalTrials.gov: NCT01471522).

Effect of sodium-glucose co-transporter-2 inhibitors on survival free of organ support in patients hospitalised for COVID-19 (ACTIV-4a): a pragmatic, multicentre, open-label, randomised, controlled, platform trial.

BACKGROUND: Patients hospitalised for COVID-19 are at risk for multiorgan failure and death. Sodium-glucose co-transporter-2 (SGLT2) inhibitors provide cardiovascular and kidney protection in patients with cardiometabolic conditions and could provide organ protection during COVID-19. We aimed to investigate whether SGLT2 inhibitors can reduce the need for organ support in patients hospitalised for COVID-19. METHODS: This pragmatic, multicentre, open-label, randomised, controlled, platform trial was conducted across 63 sites in the USA, Spain, Brazil, Italy, and Mexico. Patients aged at least 18 years hospitalised for COVID-19 (moderate or severe illness) were randomly assigned (1:1), via an interactive voice system or web-response system, to receive locally available SGLT2 inhibitor (administered orally, once daily) plus standard-of-care or standard-of-care for 30 days. The primary outcome was organ support-free days evaluated through 21 days, assessed using intention-to-treat approach. This trial is registered on ClinicalTrials.gov, NCT04505774. FINDINGS: The first patient was randomly assigned to the SGLT2 inhibitor domain on Dec 3, 2021. On March 31, 2023, at the recommendation of the data and safety monitoring board, enrolment in the SGLT2 inhibitor domain for both moderately and severely ill hospitalised patients was stopped prematurely for futility due to a low likelihood of finding a treatment benefit. The final randomised population consisted of 575 patients (mean age 72 years [SD 13], 242 (42%) female and 154 (27%) Hispanic; 504 in the moderate illness group and 71 in the severe illness group). 573 patients had a known 21-day outcome; 215 (75%) of 285 patients in the SGLT2 inhibitor plus standard-of-care group did not require respiratory or cardiovascular organ support versus 231 (80%) of 288 patients in the standard-of-care group. The adjusted odds ratio (OR) for an SGLT2 inhibitor effect on organ support-free days was 0·74 (95% Credible Interval [CrI] 0·48-1·13; where OR higher than 1 indicated treatment benefit, yielding a posterior probability of futility P(OR <1·2) of 99% and a posterior probability of inferiority P(OR<1·0) of 91%). There were 37 deaths (13%) in the SGLT2 inhibitor plus standard-of-care group and 42 deaths (15%) in the standard-of-care group at 90 days (hazard ratio 0·91 [95% CrI 0·58-1·43], probability of hazard ratio <1 of 66%). No safety concerns were observed with SGLT2 inhibitors, including no cases of ketoacidosis. INTERPRETATION: SGLT2 inhibitors did not significantly increase days free of organ support or reduce mortality in patients hospitalised with COVID-19. SGLT2 inhibitors were well tolerated with no observed safety concerns. Overall, these findings do not support the use of SGLT2 inhibitors as standard care in patients hospitalised with COVID-19. FUNDING: National Institutes of Health.

International Variation in Health Status Benefits in Patients Undergoing Initial Invasive Versus Conservative Management for Chronic Coronary Disease: Insights From the ISCHEMIA Trial.

BACKGROUND: The ISCHEMIA trial (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches) demonstrated greater health status benefits with an initial invasive strategy, as compared with a conservative one, for patients with chronic coronary disease and moderate or severe ischemia. Whether these benefits vary globally is important to understand to support global adoption of the results. METHODS: We analyzed participants' disease-specific health status using the validated 7-item Seattle Angina Questionnaire (SAQ: >5-point differences are clinically important) at baseline and over 1-year follow-up across 37 countries in 6 international regions. The average effect of initial invasive versus conservative strategies on 1-year SAQ scores was estimated using Bayesian proportional odds regression and compared across regions. RESULTS: Considerable regional variation in baseline health status was observed among 4617 participants (mean age=64.4±9.5 years, 24% women), with the mean SAQ summary scores of 67.4±19.5 in Eastern Europe participants (17% of the total), 71.4±15.4 in Asia-Pacific (18%), 74.9±16.7 in Central and South America (10%), 75.5±19.5 in Western Europe (26%), and 78.6±19.2 in North America (28%). One-year improvements in SAQ scores were greater in regions with lower baseline scores with initial invasive management (17.7±20.9 in Eastern Europe and 11.4±19.3 in North America), but similar in the conservative arm. Adjusting for baseline SAQ scores, similar health status benefits of an initial invasive strategy on 1-year SAQ scores were observed (ranging from 2.38 points [95% CI, 0.04-4.50] in North America to 4.66 points [95% CI, 2.46-6.94] in Eastern Europe), with an 88.3% probability that the difference in benefit across regions was <5 points. CONCLUSIONS: In patients with chronic coronary disease and moderate or severe ischemia, initial invasive management was associated with a consistent health status benefit across regions, with modest regional variability, supporting the international generalizability of health status benefits from invasive management of chronic coronary disease. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01471522.

Atherosclerosis quantification and cardiovascular risk: the ISCHEMIA trial.

BACKGROUND AND AIMS: The aim of this study was to determine the prognostic value of coronary computed tomography angiography (CCTA)-derived atherosclerotic plaque analysis in ISCHEMIA. METHODS: Atherosclerosis imaging quantitative computed tomography (AI-QCT) was performed on all available baseline CCTAs to quantify plaque volume, composition, and distribution. Multivariable Cox regression was used to examine the association between baseline risk factors (age, sex, smoking, diabetes, hypertension, ejection fraction, prior coronary disease, estimated glomerular filtration rate, and statin use), number of diseased vessels, atherosclerotic plaque characteristics determined by AI-QCT, and a composite primary outcome of cardiovascular death or myocardial infarction over a median follow-up of 3.3 (interquartile range 2.2-4.4) years. The predictive value of plaque quantification over risk factors was compared in an area under the curve (AUC) analysis. RESULTS: Analysable CCTA data were available from 3711 participants (mean age 64 years, 21% female, 79% multivessel coronary artery disease). Amongst the AI-QCT variables, total plaque volume was most strongly associated with the primary outcome (adjusted hazard ratio 1.56, 95% confidence interval 1.25-1.97 per interquartile range increase [559 mm3]; P = .001). The addition of AI-QCT plaque quantification and characterization to baseline risk factors improved the model's predictive value for the primary outcome at 6 months (AUC 0.688 vs. 0.637; P = .006), at 2 years (AUC 0.660 vs. 0.617; P = .003), and at 4 years of follow-up (AUC 0.654 vs. 0.608; P = .002). The findings were similar for the other reported outcomes. CONCLUSIONS: In ISCHEMIA, total plaque volume was associated with cardiovascular death or myocardial infarction. In this highly diseased, high-risk population, enhanced assessment of atherosclerotic burden using AI-QCT-derived measures of plaque volume and composition modestly improved event prediction.

How to Use Cardiac Magnetic Resonance Imaging in Myocardial Infarction With Nonobstructive Coronary Arteries.

The working diagnosis Myocardial Infarction with Nonobstructive Coronary Arteries (MINOCA) is being increasingly recognized with the common use of high-sensitivity troponins and coronary angiography, accounting for 5% to 10% of all acute myocardial infarction presentations. Cardiac magnetic resonance (CMR) imaging is pivotal in patients presenting with suspected MINOCA, mainly to delineate those with a nonischemic cause, for example, myocarditis and Takotsubo syndrome, from those with true ischemic myocardial infarction, that is, MINOCA. The optimal timing for CMR imaging in patients with suspected MINOCA has been uncertain and, until recently, not been examined prospectively. Previous retrospective studies have indicated that the diagnostic yield decreases with time from the acute event. The SMINC studies (Stockholm Myocardial Infarction with Normal Coronaries) show that CMR should be performed early in all patients with the working diagnosis of MINOCA, with the possible exception of patients who are clearly identified as having Takotsubo syndrome as determined by echocardiography. In addition to CMR imaging, other investigations of importance in selected patients may be pulmonary artery computed tomography to exclude pulmonary embolism, optical coherence tomography to identify plaque disruption, and acetylcholine provocation to identify coronary artery spasm. Imaging of patients with the working diagnosis MINOCA, which is centered on CMR together with supplemental investigations, results in a clear diagnosis in approximately three-quarters of the patients. This is a good example of personalized medicine, because a correct diagnosis will not only increase the satisfaction of the individual patient but also result in optimizing treatment without harming the patient.

Myocardial infarction with nonobstructive coronary arteries: a single-center retrospective study by sex and race.

BACKGROUND: In myocardial infarction with nonobstructive coronary arteries (MINOCA), there are limited patient-level data on outcomes by sex and race. OBJECTIVE: The aim of this study was to assess baseline demographics and 3-year outcomes by sex and race for MINOCA patients. METHODS: Patients admitted to a single center with acute myocardial infarction (MI) between 1 January 2012 and 31 December 2018, were identified by chart and angiographic review. The primary outcome was nonfatal MI with secondary outcomes including nonfatal cerebrovascular accident (CVA), chest pain readmission, and repeat coronary angiography. RESULTS: During the study period, 304 patients were admitted with MINOCA. The cohort was predominantly female (66.4%), and women were significantly older (64.6 vs. 59.2). One-sixth of the total population were Black patients, and nearly half of Black patients (47.2%) were male. Prior CVA (19.7%) and comorbid anxiety, depression, or post-traumatic stress disorder (41.1%) were common. Rates of nonfatal MI were 6.3% without difference by sex or race. For secondary outcomes, rates of CVA were 1.7%, chest pain readmission was 22.4%, and repeat angiography was 8.9%. Men were significantly more likely to have repeat angiography (13.7 vs. 6.4%), and Black patients were more likely to be readmitted for angina (34.0 vs. 19.1%). Over one-quarter of patients underwent repeat stress testing, with 8.9% ultimately undergoing repeat angiograms and low numbers (0.7%) undergoing revascularization. Men were more likely to be referred for a repeat angiogram (13.7 vs. 6.4%, P  = 0.035). In multivariate analysis, Black race [odds ratio (OR), 2.31; 95% confidence interval (CI), 1.06-5.03] was associated with an increased risk of readmission for angina, while female sex was associated with decreased odds of repeat angiography (OR, 0.36; 95% CI, 0.14-0.90) and current smoking was associated with increased odds of repeat angiography (OR, 4.07; 95% CI, 1.02-16.29)] along with hyperlipidemia (OR, 4.65; 95% CI, 1.22-17.7). CONCLUSION: White women presented more frequently with MINOCA than White men, however, Black men are equally as affected as Black women. Rates of nonfatal MI were low without statistical differences by sex or race.

Heparin Dose Intensity and Organ Support-Free Days in Patients Hospitalized for COVID-19.

Background: Clinical trials suggest that therapeutic-dose heparin may prevent critical illness and vascular complications due to COVID-19, but knowledge gaps exist regarding the efficacy of therapeutic heparin including its comparative effect relative to intermediate-dose anticoagulation. Objectives: The authors performed 2 complementary secondary analyses of a completed randomized clinical trial: 1) a prespecified per-protocol analysis; and 2) an exploratory dose-based analysis to compare the effect of therapeutic-dose heparin with low- and intermediate-dose heparin. Methods: Patients who received initial anticoagulation dosed consistently with randomization were included. The primary outcome was organ support-free days (OSFDs), a combination of in-hospital death and days free of organ support through day 21. Results: Among 2,860 participants, 1,761 (92.8%) noncritically ill and 857 (89.1%) critically ill patients were treated per-protocol. Among noncritically ill per-protocol patients, the posterior probability that therapeutic-dose heparin improved OSFDs as compared with usual care was 99.3% (median adjusted OR: 1.36; 95% credible interval [CrI]: 1.07-1.74). Therapeutic heparin had a high posterior probability of efficacy relative to both low- (94.6%; adjusted OR: 1.26; 95% CrI: 0.95-1.64) and intermediate- (99.8%; adjusted OR: 1.80; 95% CrI: 1.22-2.62) dose thromboprophylaxis. Among critically ill per-protocol patients, the posterior probability that therapeutic heparin improved outcomes was low. Conclusions: Among noncritically ill patients hospitalized for COVID-19 who were randomized to and initially received therapeutic-dose anticoagulation, heparin, compared with usual care, was associated with improved OSFDs, a combination of in-hospital death and days free of organ support. Therapeutic heparin appeared superior to both low- and intermediate-dose thromboprophylaxis.

Cardiometabolic Co-morbidity Burden and Circulating Biomarkers in Patients With Chronic Coronary Disease in the ISCHEMIA Trials.

Cardiometabolic co-morbidities, diabetes (DM), hypertension (HTN), and obesity contribute to cardiovascular disease. Circulating biomarkers facilitate prognostication for patients with cardiovascular disease. We explored the relation between cardiometabolic co-morbidity burden in patients with chronic coronary disease and biomarkers of myocardial stretch, injury, inflammation, and platelet activity. We analyzed participants from the International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA) trials biorepository with plasma biomarkers (N-terminal probrain natriuretic peptide, high-sensitivity cardiac troponin T, high-sensitivity C-reactive protein, interleukin-6, soluble CD40 ligand, and growth differentiation factor-15) and clinical risk factors (hemoglobin A1c [HbA1c], systolic blood pressure [SBP], and body mass index [BMI]) at baseline. We defined cardiometabolic co-morbidities as DM, HTN, and obesity at baseline. Co-morbidity burden is characterized by the number and severity of co-morbidities. Controlled co-morbidities were defined as HbA1c <7% for those with DM, SBP <130 mm Hg for those with HTN, and BMI <30 kg/m2. Severely uncontrolled was defined as HbA1c ≥8%, SBP ≥160 mm Hg, and BMI ≥35 kg/m2. We performed linear regression analyses to examine the association between co-morbidity burden and log-transformed biomarker levels, adjusting for age, gender, estimated glomerular filtration rate controlled for hemodialysis, and left ventricular ejection fraction. A total of 752 participants (mean age 66 years, 19% women, 84% White) were included in this analysis. Self-reported Black race, current smokers, history of myocardial infarction, and heart failure had a greater cardiometabolic co-morbidity burden. The presence of ≥1 severely uncontrolled co-morbidity was associated with significantly higher baseline levels of high-sensitivity cardiac troponin T, high-sensitivity C-reactive protein, interleukin-6, and growth differentiation factor-15 than participants with no co-morbidities. In conclusion, increasing cardiometabolic co-morbidity burden in patients with chronic coronary disease is associated with higher levels of circulating biomarkers of myocardial injury and inflammation.

Comparison of Bayesian and frequentist monitoring boundaries motivated by the Multiplatform Randomized Clinical Trial.

BACKGROUND: The coronavirus disease 2019 pandemic highlighted the need to conduct efficient randomized clinical trials with interim monitoring guidelines for efficacy and futility. Several randomized coronavirus disease 2019 trials, including the Multiplatform Randomized Clinical Trial (mpRCT), used Bayesian guidelines with the belief that they would lead to quicker efficacy or futility decisions than traditional "frequentist" guidelines, such as spending functions and conditional power. We explore this belief using an intuitive interpretation of Bayesian methods as translating prior opinion about the treatment effect into imaginary prior data. These imaginary observations are then combined with actual observations from the trial to make conclusions. Using this approach, we show that the Bayesian efficacy boundary used in mpRCT is actually quite similar to the frequentist Pocock boundary. METHODS: The mpRCT's efficacy monitoring guideline considered stopping if, given the observed data, there was greater than 99% probability that the treatment was effective (odds ratio greater than 1). The mpRCT's futility monitoring guideline considered stopping if, given the observed data, there was greater than 95% probability that the treatment was less than 20% effective (odds ratio less than 1.2). The mpRCT used a normal prior distribution that can be thought of as supplementing the actual patients' data with imaginary patients' data. We explore the effects of varying probability thresholds and the prior-to-actual patient ratio in the mpRCT and compare the resulting Bayesian efficacy monitoring guidelines to the well-known frequentist Pocock and O'Brien-Fleming efficacy guidelines. We also contrast Bayesian futility guidelines with a more traditional 20% conditional power futility guideline. RESULTS: A Bayesian efficacy and futility monitoring boundary using a neutral, weakly informative prior distribution and a fixed probability threshold at all interim analyses is more aggressive than the commonly used O'Brien-Fleming efficacy boundary coupled with a 20% conditional power threshold for futility. The trade-off is that more aggressive boundaries tend to stop trials earlier, but incur a loss of power. Interestingly, the Bayesian efficacy boundary with 99% probability threshold is very similar to the classic Pocock efficacy boundary. CONCLUSIONS: In a pandemic where quickly weeding out ineffective treatments and identifying effective treatments is paramount, aggressive monitoring may be preferred to conservative approaches, such as the O'Brien-Fleming boundary. This can be accomplished with either Bayesian or frequentist methods.

Variation in Health Status With Invasive vs Conservative Management of Chronic Coronary Disease.

BACKGROUND: The ISCHEMIA trial found that patients with chronic coronary disease randomized to invasive strategy had better health status than those randomized to conservative strategy. It is unclear how best to translate these population-level results to individual patients. OBJECTIVES: The authors sought to identify patient characteristics associated with health status from invasive and conservative strategies, and develop a prediction algorithm for shared decision-making. METHODS: One-year disease-specific health status was assessed in ISCHEMIA with the Seattle Angina Questionnaire (SAQ) Summary Score (SAQ SS) and Angina Frequency, Physical Limitations (PL), and Quality of Life (QL) domains (range 0-100, higher = less angina/better health status). RESULTS: Among 4,617 patients from 320 sites in 37 countries, mean SAQ SS was 74.1 ± 18.9 at baseline and 85.7 ± 15.6 at 1 year. Lower baseline SAQ SS and younger age were associated with better 1-year health status with invasive strategy (P interaction = 0.009 and P interaction = 0.004, respectively). For the individual domains, there were significant treatment interactions for baseline SAQ score (Angina Frequency, PL), age (PL, QL), anterior ischemia (PL), and number of baseline antianginal medications (QL), with more benefit of invasive in patients with worse baseline health status, younger age, anterior ischemia, and on more antianginal medications. Parsimonious prediction models were developed for 1-year SAQ domains with invasive or conservative strategies to support shared decision-making. CONCLUSIONS: In the management of chronic coronary disease, individual patient characteristics are associated with 1-year health status, with younger age and poorer angina-related health status showing greater benefit from invasive management. This prediction algorithm can support the translation of the ISCHEMIA trial results to individual patients. (International Study of Comparative Health Effectiveness With Medical and Invasive Approaches [ISCHEMIA]; NCT01471522).

Angiographic Coronary Slow Flow Is Not a Valid Surrogate for Invasively Diagnosed Coronary Microvascular Dysfunction.

BACKGROUND: Ischemia with no obstructive coronary arteries is frequently caused by coronary microvascular dysfunction (CMD). Consensus diagnostic criteria for CMD include baseline angiographic slow flow by corrected TIMI (Thrombolysis In Myocardial Infarction) frame count (cTFC), but correlations between slow flow and CMD measured by invasive coronary function testing (CFT) are uncertain. OBJECTIVES: The aim of this study was to investigate relationships between cTFC and invasive CFT for CMD. METHODS: Adults with ischemia with no obstructive coronary arteries underwent invasive CFT with thermodilution-derived baseline coronary blood flow, coronary flow reserve (CFR), and index of microcirculatory resistance (IMR). CMD was defined as abnormal CFR (<2.5) and/or abnormal IMR (≥25). cTFC was measured from baseline angiography; slow flow was defined as cTFC >25. Correlations between cTFC and baseline coronary flow and between CFR and IMR and associations between slow flow and invasive measures of CMD were evaluated, adjusted for covariates. All patients provided consent. RESULTS: Among 508 adults, 49% had coronary slow flow. Patients with slow flow were more likely to have abnormal IMR (36% vs 26%; P = 0.019) but less likely to have abnormal CFR (28% vs 42%; P = 0.001), with no difference in CMD (46% vs 51%). cTFC was weakly correlated with baseline coronary blood flow (r = -0.35; 95% CI: -0.42 to -0.27), CFR (r = 0.20; 95% CI: 0.12 to 0.28), and IMR (r = 0.16; 95% CI: 0.07-0.24). In multivariable models, slow flow was associated with lower odds of abnormal CFR (adjusted OR: 0.53; 95% CI: 0.35 to 0.80). CONCLUSIONS: Coronary slow flow was weakly associated with results of invasive CFT and should not be used as a surrogate for the invasive diagnosis of CMD.

Visual Estimates of Coronary Slow Flow Are Not Associated With Invasive Wire-Based Diagnoses of Coronary Microvascular Dysfunction.

BACKGROUND: Coronary slow flow (CSF) by invasive coronary angiography is frequently understood to be an indicator of coronary microvascular dysfunction (CMD) in patients with ischemia with nonobstructive coronary arteries. However, the relationship between visual estimates of CSF and quantitative wire-based invasive diagnosis of CMD is uncertain. METHODS: We prospectively enrolled adults aged ≥18 years with stable ischemic heart disease who were referred for invasive coronary angiography. Individuals with ≥50% epicardial coronary artery stenosis were excluded. Invasive coronary angiography was reviewed for CSF, defined as ≥3 cardiac cycles to opacify distal vessels with contrast. Coronary function testing was performed in the left anterior descending coronary artery using bolus coronary thermodilution techniques to measure coronary flow reserve (CFR) and the index of microcirculatory resistance (IMR). Invasively determined CMD was defined as abnormal CFR (<2.5), abnormal IMR (≥25), or both. RESULTS: Among 104 participants, the median age was 61.5 years and 79% were female. The median CFR was 3.6 (interquartile range, 2.5-4.7) and the median IMR was 21 (interquartile range, 13.3-28.0). Overall, 24.0% of participants had abnormal CFR, 34.6% had abnormal IMR, and 48.1% had a final diagnosis of invasively determined CMD. CSF was present in 23 participants (22.1%). The proportions of patients with CMD (56.5% versus 45.7%; P=0.36), abnormal CFR (17.4% versus 25.9%; P=0.40), and abnormal IMR (43.5% versus 32.1%; P=0.31) were not different in patients with versus without CSF. CONCLUSIONS: Among patients with ischemia with nonobstructive coronary artery, CSF was not associated with abnormal CFR, IMR, or either abnormal CFR or IMR. CSF is not a reliable angiographic surrogate of abnormal CFR or IMR as determined by invasive, wire-based physiology testing. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03537586.

Factors Associated With Coronary Angiography Performed Within 6 Months of Randomization to the Conservative Strategy in the ISCHEMIA Trial.

BACKGROUND: ISCHEMIA (International Study of Comparative Health Effectiveness With Medical and Invasive Approaches) did not find an overall reduction in cardiovascular events with an initial invasive versus conservative management strategy in chronic coronary disease; however, there were conservative strategy participants who underwent invasive coronary angiography early postrandomization (within 6 months). Identifying factors associated with angiography in conservative strategy participants will inform clinical decision-making in patients with chronic coronary disease. METHODS: Factors independently associated with angiography performed within 6 months of randomization were identified using Fine and Gray proportional subdistribution hazard models, including demographics, region of randomization, medical history, risk factor control, symptoms, ischemia severity, coronary anatomy based on protocol-mandated coronary computed tomography angiography, and medication use. RESULTS: Among 2591 conservative strategy participants, angiography within 6 months of randomization occurred in 8.7% (4.7% for a suspected primary end point event, 1.6% for persistent symptoms, and 2.6% due to protocol nonadherence) and was associated with the following baseline characteristics: enrollment in Europe versus Asia (hazard ratio [HR], 1.81 [95% CI, 1.14-2.86]), daily and weekly versus no angina (HR, 5.97 [95% CI, 2.78-12.86] and 2.63 [95% CI, 1.51-4.58], respectively), poor to fair versus good to excellent health status (HR, 2.02 [95% CI, 1.23-3.32]) assessed with Seattle Angina Questionnaire, and new/more frequent angina prerandomization (HR, 1.80 [95% CI, 1.34-2.40]). Baseline low-density lipoprotein cholesterol <70 mg/dL was associated with a lower risk of angiography (HR, 0.65 [95% CI, 0.46-0.91) but not baseline ischemia severity nor the presence of multivessel or proximal left anterior descending artery stenosis >70% on coronary computed tomography angiography. CONCLUSIONS: Among ISCHEMIA participants randomized to the conservative strategy, angiography within 6 months of randomization was performed in <10% of patients. It was associated with frequent or increasing baseline angina and poor quality of life but not with objective markers of disease severity. Well-controlled baseline low-density lipoprotein cholesterol was associated with a reduced likelihood of angiography. These findings point to the importance of a comprehensive assessment of symptoms and a review of guideline-directed medical therapy goals when deciding the initial treatment strategy for chronic coronary disease. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01471522.

Sex Differences in Revascularization, Treatment Goals, and Outcomes of Patients With Chronic Coronary Disease: Insights From the ISCHEMIA Trial.

BACKGROUND: Women with chronic coronary disease are generally older than men and have more comorbidities but less atherosclerosis. We explored sex differences in revascularization, guideline-directed medical therapy, and outcomes among patients with chronic coronary disease with ischemia on stress testing, with and without invasive management. METHODS AND RESULTS: The ISCHEMIA (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches) trial randomized patients with moderate or severe ischemia to invasive management with angiography, revascularization, and guideline-directed medical therapy, or initial conservative management with guideline-directed medical therapy alone. We evaluated the primary outcome (cardiovascular death, myocardial infarction, or hospitalization for unstable angina, heart failure, or resuscitated cardiac arrest) and other end points, by sex, in 1168 (22.6%) women and 4011 (77.4%) men. Invasive group catheterization rates were similar, with less revascularization among women (73.4% of invasive-assigned women revascularized versus 81.2% of invasive-assigned men; P<0.001). Women had less coronary artery disease: multivessel in 60.0% of invasive-assigned women and 74.8% of invasive-assigned men, and no ≥50% stenosis in 12.3% versus 4.5% (P<0.001). In the conservative group, 4-year catheterization rates were 26.3% of women versus 25.6% of men (P=0.72). Guideline-directed medical therapy use was lower among women with fewer risk factor goals attained. There were no sex differences in the primary outcome (adjusted hazard ratio [HR] for women versus men, 0.93 [95% CI, 0.77-1.13]; P=0.47) or the major secondary outcome of cardiovascular death/myocardial infarction (adjusted HR, 0.93 [95% CI, 0.76-1.14]; P=0.49), with no significant sex-by-treatment-group interactions. CONCLUSIONS: Women had less extensive coronary artery disease and, therefore, lower revascularization rates in the invasive group. Despite lower risk factor goal attainment, women with chronic coronary disease experienced similar risk-adjusted outcomes to men in the ISCHEMIA trial. REGISTRATION: URL: http://wwwclinicaltrials.gov. Unique identifier: NCT01471522.