Neuromodulation of Cardiac Ischemic Pain: Role of the Autonomic Nervous System and Vasopressin.

Cardiac pain is an index of cardiac ischemia that helps the detection of cardiac hypoxia and adjustment of activity in the sufferer. Drivers and thresholds of cardiac pain markedly differ in different subjects and can oscillate in the same individual, showing a distinct circadian rhythmicity and clinical picture. In patients with syndrome X or silent ischemia, cardiac pain intensity may cause neurogenic stress that potentiates the cardiac work and intensifies the cardiac hypoxia and discomfort of the patient. The reasons for individual differences in cardiac pain sensation are not fully understood. Thus far, most attention has been focused on inappropriate regulation of the heart by the autonomic nervous system, autacoids, and cardiovascular hormones. Herein, we summarize evidence showing that the autonomic nervous system regulates cardiac pain sensation in cooperation with vasopressin (AVP). AVP is an essential analgesic compound and it exerts its antinociceptive function through actions in the brain (the periaqueductal gray, caudate nucleus, nucleus raphe magnus), spinal cord, and heart and coronary vessels. Vasopressin acts directly by means of V1 and V2 receptors as well as through multiple interactions with the autonomic nervous system and cardiovascular hormones, in particular, angiotensin II and endothelin. The pain regulatory effects of the autonomic nervous system and vasopressin are significantly impaired in cardiovascular diseases.

Relationship Between Myocardial Perfusion Imaging Abnormalities on Positron Emission Tomography and Anginal Symptoms, Functional Status, and Quality of Life.

BACKGROUND: Myocardial perfusion imaging (MPI) identifies abnormalities that occur early in the ischemic cascade leading to angina. Our aim was to study the association between ischemic measures on positron emission tomography MPI and patients' health status; their symptoms, function, and quality of life. METHODS: Health status was collected using the Seattle Angina Questionnaire (SAQ-7, 0-100, higher=better) and Rose Dyspnea Score (RDS) on 1515 outpatients with known or suspected coronary artery disease presenting for clinically indicated pharmacological 82Rb positron emission tomography MPI from July 2018 to July 2019. Adjusted multivariable ordinal regression models were used to assess the association between MPI findings of ischemia and the SAQ physical limitation, angina frequency, quality of life, summary score, and the RDS. RESULTS: The mean SAQ and RDS scores of the cohort (mean age 71.7 years, 55% male, 37.6% prior myocardial infarction or revascularization) were 73.8±28.6 (physical limitation), 87.4±21.7 (angina frequency), 79.0±26.1 (quality of life), 81.3±19.0 (summary score), and 2±2 (RDS). No perfusion, flow or function abnormalities were significantly associated with SAQ angina frequency scores. Low left ventricular ejection fraction reserve (≤0%), low global and regional myocardial blood flow reserve (<2) were independently associated with worse SAQ Physical Limitation score, SAQ summary score, and RDS (30% to 57% greater odds; all P≤0.01), but reversible perfusion defects were not. CONCLUSIONS: Impaired augmentation of left ventricular ejection fraction and myocardial blood flow with stress is associated with significant angina-associated functional limitation, health status, and dyspnea in patients who underwent positron emission tomography MPI, but not the frequency of their angina. Future studies should evaluate whether therapies that improve stress-induced abnormalities in systolic function and myocardial flow may improve patients' health status.

Effectiveness of Coronary Sinus Reducer for Treatment of Refractory Angina: A Meta-analysis.

BACKGROUND: Refractory angina is a debilitating condition that affects the quality of life of patients worldwide, who after exhausting standard available therapies are regarded as "no option" patients. Recently, CS (coronary sinus) reducer (Neovasc Reducer) implantation became available and is gaining popularity in the treatment of refractory angina. The effectiveness of this therapy was demonstrated in 1 randomised sham-control trial and numerous uncontrolled prospective studies entailing several hundred patients altogether. We performed a meta-analysis to incorporate the data and elucidate its efficacy and safety. METHODS: A meta-analysis of prospective studies assessing the effects of CS narrowing published in English to June 2021 was performed. The primary outcome was the proportion of patients improving ≥ 1 class in the Canadian Cardiovascular Society (CCS) angina score. Other end points included proportion of patients improving ≥ 2 CCS classes, procedural success, periprocedural complications, changes in Seattle Angina Questionnaire (SAQ) scores, and 6-minute walk test (6MWT). RESULTS: Data from 9 studies including 846 patients were included. An improvement of ≥ 1 CCS class occurred in 76% (95% confidence interval [CI] 73%-80%) of patients. Improvement of ≥ 2 CCS classes was observed in 40% of patients (95% CI 35%-46%). Procedure success was 98%, with no major and 3% nonmajor periprocedural complications. Post procedural SAQ scores and 6MWT distance were significantly improved. CONCLUSIONS: In patients suffering from angina refractory to medical and interventional therapies, Reducer implantation improves symptoms and quality of life with a low complication rate. These results are consistent in 1 randomised trial and multiple prospective uncontrolled studies.

Incidence and Implications of J waves Observed During Coronary Angiography.

J waves may be observed during coronary angiography (CAG), but they have not been fully studied. We investigated the characteristics of J waves in 100 consecutive patients during CAG. The patients and their family members had no history of cardiac arrest. Approximately 60% of patients had ischemic heart disease, previous myocardial infarction, or angina pectoris, but at the time of this study, the right coronary artery was shown to be normal or patent after stenting. Electrocardiogram was serially recorded to monitor J waves and alteration of the QRS complex during CAG. In 12 patients (12%), J waves (0.249 ± 0.074 mV) newly appeared during right CAG, and in another 13 patients (13%), preexisting J waves increased from 0.155 ± 0.060 mV to 0.233 ± 0.133 mV during CAG. Left CAG induced no J waves or augmentation of J waves. Distinct alterations were observed in the QRS complex during CAG of both coronary arteries. Mechanistically, myocardial ischemia induced by contrast medium was considered to result in a local conduction delay, and when it occurred in the inferior wall, the site of the late activation of the ventricle, the conduction delay was manifested as J waves. In conclusion, J waves were confirmed to emerge or increase during angiography of the right but not the left coronary artery. Myocardial ischemia induced by contrast medium caused a local conduction delay that was manifested as J waves in the inferior wall, the site of the late activation of the ventricle.

Longitudinal Association Between Angina Pectoris and Quality of Life.

Angina is a common symptom in patients with coronary artery disease (CAD); however, its impact on patients' quality of life over time is not well understood. We sought to determine the longitudinal association of angina frequency with quality of life and functional status over a 5-year period. We used data from the Heart and Soul Study, a prospective cohort study of 1,023 outpatients with stable CAD. Participants completed the Seattle Angina Questionnaire (SAQ) at baseline and annually for 5 years. We evaluated the population effect of angina frequency on disease-specific quality of life (SAQ Disease Perception), physical function (SAQ Physical Limitation), perceived overall health, and overall quality of life, with adjusted models. We evaluated these associations within the same year and with a time-lagged association between angina and quality of life reported 1 year later. Generalized estimating equation models were used to account for repeated measures and within-subject correlation of responses. Over 5 years of follow-up, patients with daily or weekly angina symptoms had lower quality of life scores (52 vs 89, p <0.001) and greater physical limitation (61 vs 86, p <0.001) after adjustment. Compared with patients with daily or weekly angina symptoms, those with no angina symptoms had 2-fold greater odds of better quality of life (odds ratio 2.39, 95% confidence interval 1.76 to 3.25) and 5-fold greater odds of better perceived overall health (odds ratio 5.45, 95% confidence interval 3.85 to 7.73). In conclusion, angina frequency is strongly associated with quality of life and physical function in patients with CAD. Even after modeling to adjust for both clinical risk factors and repeated measures within subjects, we found that less frequent angina symptoms were associated with better quality of life.

Circulating humanin is lower in coronary artery disease and is a prognostic biomarker for major cardiac events in humans.

BACKGROUND: Humanin is an endogenous mitochondria-derived peptide that plays critical roles in oxidative stress, inflammation and CAD. In this study, we measured the levels of circulating humanin, markers of oxidative stress and inflammation in patients with unstable angina and MI and studied the relationship between these parameters and major adverse cardiac events (MACE). METHODS: A total of 327 subjects were recruited from the inpatient department at First Hospital of Jilin University and divided into 3 groups [control, angina and myocardial infarction (MI)] based on the clinical data and the results of the angiography. Serum humanin and thiobarbituric acid reactive substances (TBARS) were measured at the time of initial admission. The hospitalization data and MACE of all patients were collected. RESULTS: Circulating humanin levels were lower in the angina group compared to controls [124.22 ±â€¯63.02 vs. 157.77 ±â€¯99.93 pg/ml, p < 0.05] and even lower in MI patients [67.17 ±â€¯24.35 pg/ml, p < 0.05 vs controls] and oxidative stress marker were higher in MI patients compared to the control and angina groups [12.94 ±â€¯4.55 vs. 8.26 ±â€¯1.66 vs. 9.06 ±â€¯2.47 umol/ml, p < 0.05]. Lower circulating humanin levels was an independent risk factor of MI patients. Circulating humanin levels could be used to predict MACE in angina group. CONCLUSIONS: Lower circulating humanin levels was an independent risk factor for CAD, and a potential prognostic marker for mild CAD. GENERAL SIGNIFICANCE: Humanin may become a new index for the diagnosis and treatment of CAD.

Calciprotein Particles Link Disturbed Mineral Homeostasis with Cardiovascular Disease by Causing Endothelial Dysfunction and Vascular Inflammation.

An association between high serum calcium/phosphate and cardiovascular events or death is well-established. However, a mechanistic explanation of this correlation is lacking. Here, we examined the role of calciprotein particles (CPPs), nanoscale bodies forming in the human blood upon its supersaturation with calcium and phosphate, in cardiovascular disease. The serum of patients with coronary artery disease or cerebrovascular disease displayed an increased propensity to form CPPs in combination with elevated ionised calcium as well as reduced albumin levels, altogether indicative of reduced Ca2+-binding capacity. Intravenous administration of CPPs to normolipidemic and normotensive Wistar rats provoked intimal hyperplasia and adventitial/perivascular inflammation in both balloon-injured and intact aortas in the absence of other cardiovascular risk factors. Upon the addition to primary human arterial endothelial cells, CPPs induced lysosome-dependent cell death, promoted the release of pro-inflammatory cytokines, stimulated leukocyte adhesion, and triggered endothelial-to-mesenchymal transition. We concluded that CPPs, which are formed in the blood as a result of altered mineral homeostasis, cause endothelial dysfunction and vascular inflammation, thereby contributing to the development of cardiovascular disease.

Assessing Microvascular Dysfunction in Angina With Unobstructed Coronary Arteries: JACC Review Topic of the Week.

Coronary microvascular dysfunction is a highly prevalent condition of both structural and functional coronary disorders in patients with angina and nonobstructive coronary artery disease (ANOCA). Current diagnostic modalities to assess microvascular function are related to prognosis, but these modalities have several technical shortcomings and lack the opportunity to determine true coronary blood flow and microvascular resistance. Intracoronary continuous thermodilution assessment of absolute coronary flow (Q) and microvascular resistance (R) was recently shown to be safe and feasible in ANOCA. Further exploration and implementation could lead to a better understanding and treatment of patients with ANOCA. This review discuss the coronary pathophysiology of microvascular dysfunction, provides an overview of noninvasive and invasive diagnostics, and focuses on the novel continuous thermodilution method. Finally, how these measurements of absolute Q and R could be integrated and how this would affect future clinical care are discussed.

Epicardial delivery of XC001 gene therapy for refractory angina coronary treatment (The EXACT Trial): Rationale, design, and clinical considerations.

BACKGROUND: Patients with refractory angina (RA) have poor quality of life and new therapies are needed. XC001 is a novel adenoviral vector expressing multiple isoforms of vascular endothelial growth factor (VEGF) promoting an enhanced local angiogenic effect. METHODS: The Epicardial Delivery of XC001 Gene Therapy for Refractory Angina Coronary Treatment (EXACT) trial is a 6-month (with 6-month extension) phase 1/2, first-in-human, multicenter, open-label, single-arm, dose-escalation study to evaluate the safety, tolerability, and preliminary efficacy of XC001 in patients with RA. The trial will enroll 33 patients in an initial (n = 12) ascending dose-escalation phase (1 × 109, 1 × 1010, 4 × 1010, and 1 × 1011 viral particles), followed by phase 2 (n = 21) assessing the highest tolerated dose. Patients must have stable Canadian Cardiovascular Society (CCS) class II-IV angina on maximally tolerated medical therapy without options for conventional revascularization, demonstrable ischemia on stress testing, and angina limiting exercise tolerance. XC001 will be delivered directly to ischemic myocardium via surgical transthoracic epicardial access. The primary outcome is safety via adverse event monitoring through 6 months. Efficacy assessments include difference from baseline to month 6 in time to 1 mm of ST segment depression, time to angina, and total exercise duration; myocardial blood flow at rest, and stress and coronary flow reserve by positron emission tomography; quality of life; CCS functional class; and angina frequency. CONCLUSIONS: The EXACT trial will determine whether direct intramyocardial administration of XC001 in patients with RA is safe and evaluate its effect on exercise tolerance, myocardial perfusion, angina and physical activity, informing future clinical investigation. CLINICAL TRIAL REGISTRATION: NCT04125732.

A pathophysiological compass to personalize antianginal drug treatment.

Myocardial ischaemia results from coronary macrovascular or microvascular dysfunction compromising the supply of oxygen and nutrients to the myocardium. The underlying pathophysiological processes are manifold and encompass atherosclerosis of epicardial coronary arteries, vasospasm of large or small vessels and microvascular dysfunction - the clinical relevance of which is increasingly being appreciated. Myocardial ischaemia can have a broad spectrum of clinical manifestations, together denoted as chronic coronary syndromes. The most common antianginal medications relieve symptoms by eliciting coronary vasodilatation and modulating the determinants of myocardial oxygen consumption, that is, heart rate, myocardial wall stress and ventricular contractility. In addition, cardiac substrate metabolism can be altered to alleviate ischaemia by modulating the efficiency of myocardial oxygen use. Although a universal agreement exists on the prognostic importance of lifestyle interventions and event prevention with aspirin and statin therapy, the optimal antianginal treatment for patients with chronic coronary syndromes is less well defined. The 2019 guidelines of the ESC recommend a personalized approach, in which antianginal medications are tailored towards an individual patient's comorbidities and haemodynamic profile. Although no antianginal medication improves survival, their efficacy for reducing symptoms profoundly depends on the underlying mechanism of the angina. In this Review, we provide clinicians with a rationale for when to use which compound or combination of drugs on the basis of the pathophysiology of the angina and the mode of action of antianginal medications.

Seattle Angina Pectoris Questionnaire and Canadian Cardiovascular Society Angina Categories in the Assessment of Total Coronary Atherosclerotic Burden.

The patient reported angina measurement with the Seattle Angina Questionnaire (SAQ) has shown to have prognostic implications and became an endpoint in clinical trials. Our objective was to study physician-reported and SAQ severity with the total coronary atherosclerotic burden as assessed by 4 angiographic scores. We prospectively analyzed data of consecutive patients scheduled for coronary angiography or percutaneous coronary intervention. The Canadian Cardiovascular Society (CCS) angina categories was used as physician-reported angina. SAQ domains were categorized as severe (0 to 24), moderate 25 to 75 and mild angina (>75). All angina assessments were done before coronary angiography. Gensini, Syntax, Friesinger, and Sullivan angiographic scores were used for total atherosclerotic burden quantification: 261 patients were included in the present analysis. The median age was 66.0 (59.0 to 71.8) years, 53.6% were male and 43.7% had diabetes. The median SYNTAX score was 6.0 (0 to 18.0). The worse the symptoms of CCS categories, the more severe was the atherosclerotic burden in all angiographic scores: SYNTAX (p = 0.01); Gensini (p <0.01); Friesinger (p = 0.02) and Sullivan (p = 0.03). Conversely, SAQ domains were not able to discriminate the severity of CAD in any of the scores. The only exception was the severe SAQ quality of life that had worse Gensini score than the mild SAQ quality of life (p = 0.04). In conclusion, CCS angina categories are related to the total atherosclerotic burden in coronary angiography, by all angiographic scores. SAQ domains should be used as a measure of patient functionality and quality of life but not as a measure of CAD severity.

Prevalence of Angina Among Primary Care Patients With Coronary Artery Disease.

Importance: Angina pectoris is associated with morbidity and mortality. Angina prevalence and frequency among contemporary US populations with coronary artery disease (CAD) remain incompletely defined. Objective: To ascertain the angina prevalence and frequency among stable outpatients with CAD. Design, Setting, and Participants: This cross-sectional survey study involved telephone-based administration of the Seattle Angina Questionnaire-7 (SAQ-7) between February 1, 2017, and July 31, 2017, to a nonconvenience sample of adults with established CAD who receive primary care through a large US integrated primary care network. Data analysis was performed from August 2017 to August 2019. Exposure: SAQ-7 administration. Main Outcomes and Measures: Angina prevalence and frequency were assessed using SAQ-7 question 2. Covariates associated with angina were assessed in univariable and multivariable regression. Results: Of 4139 eligible patients, 1612 responded to the survey (response rate, 38.9%). The mean (SD) age of the respondents was 71.8 (11.0) years, 577 (35.8%) were women, 1447 (89.8%) spoke English, 147 (9.1%) spoke Spanish, 1336 (82.8%) were White, 76 (4.7%) were Black, 92 (5.7%) were Hispanic, 974 (60.4%) had Medicare, and 83 (5.2%) had Medicaid. Among respondents, 342 (21.2%) reported experiencing angina at least once monthly; among those, 201 (12.5%) reported daily or weekly angina, and 141 respondents (8.7%) reported monthly angina. The mean (SD) SAQ-7 score was 93.7 (13.7). After multivariable adjustment, speaking a language other than Spanish or English (odds ratio [OR], 5.07; 95% CI, 1.39-18.50), Black race (OR, 2.01; 95% CI, 1.08-3.75), current smoking (OR, 1.88; 95% CI, 1.27-2.78), former smoking (OR, 1.69; 95% CI, 1.13-2.51), atrial fibrillation (OR, 1.52; 95% CI, 1.02-2.26), and chronic obstructive pulmonary disease (OR, 1.61; 95% CI, 1.18-2.18) were associated with more frequent angina. Male sex (OR, 0.63; 95% CI, 0.47-0.86), peripheral artery disease (OR, 0.63; 95% CI, 0.44-0.90), and novel oral anticoagulant use (OR, 0.19; 95% CI, 0.08-0.48) were associated with less frequent angina. Conclusions and Relevance: Among stable outpatients with CAD receiving primary care through an integrated primary care network, 21.2% of surveyed patients reported experiencing angina at least once monthly. Several objective demographic and clinical characteristics were associated with angina frequency. Proactive assessment of angina symptoms using validated assessment tools and estimation of patients at higher risk of suboptimally controlled angina may be associated with reduced morbidity.

Retinal changes in patients with angina pectoris and anginal equivalents: a study of patients with normal coronary angiography.

Background and aims. Approximately 10-30% of the patients with typical symptoms of angina pectoris have normal angiography showing normal macrovasculature. In these patients, however, the microvascular problems should be monitored. Hence, the main aim of this study is to evaluate retinal changes in normal angiographic patients.Methods. In this descriptive cross-sectional study, 60 normal angiographic patients with typical chest pain or anginal equivalents visiting Modarres Hospital Cardiology Research Center between 2018 and 2019 were enrolled and retinal changes were determined in Labbafinejad Hospital by Optical Coherence Tomography Angiography using Foveal Avascular Zone (FAZ), Superficial Vascular Density (SVD), and Deep Vascular Density (DVD).Results. The results of this study demonstrated that FAZ was normal in all subjects, but SVD and DVD were abnormal in 45% and 8.3%, respectively. Totally, 18.5% and 66.7% showed abnormal SVD among stable angina (SA) and unstable angina (UA) cases, respectively (P < 0.001). There was no statistically significant difference between abnormal DVD in SA and UA cases (P = 0.058). Abnormal SVD was significantly more common among diabetic patients (P < 0.001), while DVD was not related to diabetes presence in the study population (P > 0.05). Moreover, abnormal SVD was more common among patients with chest pain (P = 0.036), while there was no significant difference for DVD (P = 0.371). Interestingly, abnormal ECG was associated with both abnormal DVD and SVD.Conclusions. The results of this study showed that nearly half of the patients with angina pectoris or anginal equivalents who revealed normal angiographic findings may suffer from retinal changes. Thus, retinal assessment is needed in these patients to evaluate microvascular changes.

Interpretation of the Seattle Angina Questionnaire as an Outcome Measure in Clinical Trials and Clinical Care: A Review.

Importance: Patient-reported outcomes are increasingly used as end points in clinical trials, assessments in clinical care, and tools for population health, with an increasing role in quality assessment. For patients with coronary artery disease, the Seattle Angina Questionnaire (SAQ) has emerged as the most commonly used measure of disease-specific health status to quantify patients' symptoms of angina and the extent to which their angina affects their functioning and quality of life. This review explains how to interpret the SAQ and describes the construction and face validity of the SAQ, focusing on aligning scores and changes in scores with clinical constructs. Observations: The SAQ asks questions similar to those an experienced clinician would ask of a patient with stable ischemic heart disease. Therefore, SAQ scores can be aligned with clinical constructs (eg, scores on the SAQ angina frequency scale of 0-30 points indicate daily angina, 31-60 points indicate weekly angina, 61-99 points indicate monthly angina, and 100 points indicate no angina), and changes in scores can be described by aligning them with changes in question responses. After clinical thresholds are defined, it is important for clinical trials to not simply report mean differences between treatment arms but to also report the distributions of patients who have had clinically important benefits so that a number needed to treat can be generated. Conclusions and Relevance: The widespread use of the SAQ is a consequence of its well-established validity, reproducibility, prognostic importance, and sensitivity to clinical change. Nevertheless, interpreting the SAQ can be challenging because of lack of familiarity with the clinical importance of its domains, either cross-sectionally or longitudinally. This review provides an overview of the interpretability of the SAQ as a foundation for its use as an end point in clinical trials, a tool to support more patient-centered care, and a means of facilitating population health strategies to provide a better foundation for the integration of patient experiences with clinical care.

Coronary artery lumen complexity as a new marker for refractory symptoms in patients with vasospastic angina.

Refractory angina is an independent predictor of adverse events in patients with vasospastic angina (VSA). The aim of this study was to investigate the relationship between coronary lumen complexity and refractory symptoms in patients with VSA. Seventeen patients with VSA underwent optical coherence tomography. The patients were divided into the refractory VSA group (n = 9) and the stable VSA group (n = 8). A shoreline development index was used to assess the coronary artery lumen complexity. Shear stress was estimated using a computational fluid dynamics model. No difference was observed in the baseline characteristics between the two groups. The refractory VSA group showed the higher shoreline development index (refractory VSA 1.042 [1.017-1.188] vs stable VSA 1.003 [1.006-1.025], p = 0.036), and higher maximum medial thickness (refractory VSA 184 ± 17 µm vs stable VSA 148 ± 31 µm, p = 0.017), and higher maximum shear stress (refractory VSA 14.5 [12.1-18.8] Pa vs stable VSA 5.6 [3.0-10.5] Pa, p = 0.003). The shoreline development index positively correlates with shear stress (R2 = 0.46, P = 0.004). Increased medial thickness of the coronary arteries provokes lumen complexity and high shear stress, which might cause refractory symptoms in patients with VSA. The shoreline index could serve as a marker for irritability of the medial layer of coronary arteries and symptoms.

Evaluation of non-invasive imaging parameters in coronary microvascular disease: a systematic review.

BACKGROUND: Coronary microvascular dysfunction (CMD) is an important underlying cause of angina pectoris. Currently, no diagnostic tool is available to directly visualize the coronary microvasculature. Invasive microvascular reactivity testing is the diagnostic standard for CMD, but several non-invasive imaging techniques are being evaluated. However, evidence on reported non-invasive parameters and cut-off values is limited. Thus, we aimed to provide an overview of reported non-invasive parameters and corresponding cut-off values for CMD. METHODS: Pubmed and EMBASE databases were systematically searched for studies enrolling patients with angina pectoris without obstructed coronary arteries, investigating at least one non-invasive imaging technique to quantify CMD. Methodological quality assessment of included studies was performed using QUADAS-2. RESULTS: Thirty-seven studies were included. Ten cardiac magnetic resonance studies reported MPRI and nine positron emission tomography (PET) and transthoracic echocardiography (TTE) studies reported CFR. Mean MPRI ranged from 1.47 ± 0.36 to 2.01 ± 0.41 in patients and from 1.50 ± 0.47 to 2.68 ± 0.49 in controls without CMD. Reported mean CFR in PET and TTE ranged from 1.39 ± 0.31 to 2.85 ± 1.35 and 1.69 ± 0.40 to 2.40 ± 0.40 for patients, and 2.68 ± 0.83 to 4.32 ± 1.78 and 2.65 ± 0.65 to 3.31 ± 1.10 for controls, respectively. CONCLUSIONS: This systematic review summarized current evidence on reported parameters and cut-off values to diagnose CMD for various non-invasive imaging modalities. In current clinical practice, CMD is generally diagnosed with a CFR less than 2.0. However, due to heterogeneity in methodology and reporting of outcome measures, outcomes could not be compared and no definite reference values could be provided.

Combined stress myocardial CT perfusion and coronary CT angiography as a feasible strategy among patients presenting with acute chest pain to the emergency department.

BACKGROUND: A combined approach of myocardial CT perfusion (CTP) with coronary CT angiography (CTA) was shown to have better diagnostic accuracy than coronary CTA alone. However, data on cost benefits and length of stay when compared to other perfusion imaging modalities has not been evaluated. Therefore, we aim to perform a feasibility study to assess direct costs and length of stay of a combined stress CTP/CTA and use SPECT myocardial perfusion imaging (SPECT-MPI) as a benchmark, among chest pain patients at intermediate-risk for acute coronary syndrome (ACS) presenting to the emergency department (ED). METHODS: This is a prospective two-arm clinical trial (NCT02538861) with 43 patients enrolled in stress CTP/CTA arm (General Electric Revolution CT) and 102 in SPECT-MPI arm. Mean age of the study population was 65 â€‹± â€‹12 years; 56% were men. We used multivariable linear regression analysis to compare length of stay and direct costs between the two modalities. RESULTS: Overall, 9 out of the 43 patients (21%) with CTP/CTA testing had an abnormal test. Of these 9 patients, 7 patients underwent invasive coronary angiography and 6 patients were found to have obstructive coronary artery disease. Normal CTP/CTA test was found in 34 patients (79%), who were discharged home and all patients were free of major adverse cardiac events at 30 days. The mean length of stay was significantly shorter by 28% (mean difference: 14.7 â€‹h; 95% CI: 0.7, 21) among stress CTP/CTA (20 â€‹h [IQR: 16, 37]) compared to SPECT-MPI (30 â€‹h [IQR: 19, 44.5]). Mean direct costs were significantly lower by 44% (mean difference: $1535; 95% CI: 987, 2082) among stress CTA/CTP ($1750 [IQR: 1474, 2114] compared to SPECT-MPI ($2837 [IQR: 2491, 3554]). CONCLUSION: Combined stress CTP/CTA is a feasible strategy for evaluation of chest pain patients presenting to ED at intermediate-risk for ACS and has the potential to lead to shorter length of stay and lower direct costs.

Pre-infarction angina is associated with improved prognosis in diabetic patients with ST-elevation myocardial infarction - data from a contemporary cohort.

BACKGROUND: Pre-infarction angina (PIA) is associated with improved prognosis in patients with ST-elevation myocardial infarction (STEMI). Some studies suggest that diabetes may blunt the effect of ischaemic preconditioning. We sought to study the impact of PIA in diabetic patients with STEMI. METHODS: Consecutive patients with STEMI who underwent primary angioplasty were included. PIA was defined as ≥1 episode of chest pain during the week preceding STEMI diagnosis. Incident major adverse cardiovascular events (MACE) were defined as the first occurrence of all-cause death, stroke or acute myocardial infarction. RESULTS: Of the 1143 included patients, 25% were diabetic and 32% had a history of PIA. Diabetic patients with PIA had smaller infarct sizes as estimated by peak creatine kinase (CK) [1144 (500-2212) vs. 1715 (908-3309) U/L, P = 0.003] and peak troponin [3.30 (1.90-6.58) vs. 4.88 (2.50-9.58) ng/ml, P = 0.002], compared to diabetics without PIA. They also had a lower likelihood of evolving with moderate to severe reduced left ventricle ejection fraction (LVEF) (25.6%, n = 22 vs. 46.6%, n = 82, P = 0.001). In non-diabetic patients, PIA was associated with reduced peak CK [1549 (909-2909) vs. 1793 (996-3078), P = 0.0497], but not troponin (3.74 [2.23-7.11] vs. 4.56 [2.44-7.77] ng/ml, P = 0.19), and was not associated with reduced LVEF (32.0%, n = 85 vs. 37.4%, n = 207, P = 0.13). Both diabetic and non-diabetic patients with PIA had a lower likelihood of evolving with a Killip class III/VI (non-diabetic patients: 5.6% vs. 14.1%, P = 0.002; diabetic patients: 12.8% vs. 24.6%, P = 0.049). Over a median follow-up of 18.0 (12.1-25.5) months, PIA was associated with a significant reduction in the incidence of MACE [hazard ratio 0.52, 95% confidence interval (CI) 0.37-0.74, P < 0.001], irrespective of diabetes status. CONCLUSION: PIA is an independent predictor of favourable outcomes in the setting of STEMI for both diabetic and non-diabetic patients.

Different vasoreactivity of arterial bypass grafts versus native coronary arteries in response to acetylcholine.

BACKGROUND: Coronary angiography is often performed in patients with recurrent angina after successful coronary artery bypass grafting (CABG) in search of the progression of atherosclerosis. However, in many of these patients, no relevant stenosis can be detected. We speculate that coronary spasm may be associated with angina in these patients. METHODS: From 2307 patients with unobstructed coronaries who underwent intracoronary acetylcholine spasm provocation testing (ACh-test) between 2012 and 2016, 54 consecutive patients who fulfilled the following inclusion criteria were included in this cohort study: previous left internal thoracic artery (LITA) bypass on the left anterior descending (LAD) coronary artery, ongoing/recurrent angina pectoris, no significant (< 50%) coronary artery or bypass stenosis. In all participants, the ACh-test was performed via the LITA bypass. RESULTS: In 14 patients (26%) the ACh-test elicited epicardial spasm of the LAD distal to the anastomosis (≥ 90% diameter reduction with reproduction of the patient's symptoms and ischemic ECG shifts). Microvascular spasm (reproduction of symptoms and ischemic ECG-changes but no epicardial spasm) was seen in 30 patients (55%). The ACh-test was normal in the remaining 10 patients (19%). ACh-testing did not elicit any relevant vasoconstriction in the LITA bypasses in contrast to the LAD on quantitative coronary analyses (4.89 ± 7.36% vs. 52.43 ± 36.07%, p < 0.01). CONCLUSION: Epicardial and microvascular coronary artery spasm are frequent findings in patients with ongoing or recurrent angina after CABG but no relevant stenosis. Vasoreactivity to acetylcholine is markedly different between LITA bypasses and native LAD arteries with vasoconstriction almost exclusively occurring in the LAD.