Suspected Angina Pectoris Research Articles

Coronary microvascular resistance comparison of coronary arteries with and without considering vascular diameter: A retrospective, single-center study.

Measurement of coronary microvascular resistance (MR) is essential for diagnosing nonocclusive coronary artery ischemia, but whether coronary branches of different diameters can be similarly assessed using hyperemic microvascular resistance index (hMVRI) calculated from average peak velocity (APV) remains unclear. We investigated the relationship between coronary arteries of different diameters and hMVRI. Thirty patients with suspected angina pectoris and nonobstructive coronary stenosis with fractional flow reserve >0.8 underwent evaluation of all coronary arteries using a Doppler velocity and pressure-equipped guidewire. Quantitative coronary angiography (QCA) was used to analyze vessel diameter (DQCA). Coronary blood flow (CBFQCA) was calculated as πDQCA 2/4 (0.5 × APV) and hMVRIQCA as distal coronary pressure divided by CBFQCA during maximal hyperemia. The hMVRI was significantly higher for the right coronary artery than for the left anterior descending artery, but no significant differences between arteries were seen for CBFQCA and hMVRIQCA. Although the correlation between CBFQCA and APV was weak, CBFQCA divided into three groups according to DQCA showed very strong correlations with APV. Slopes of the straight line between APV and CBFQCA for small-, middle-, and large-diameter groups were 0.48, 0.30, and 0.21, respectively, with slope decreasing as diameter increased. Comparative evaluation of MR in coronary branches with varying vessel diameters requires vessel diameter to be accounted for.

Deep learning to predict long-term mortality from plain chest radiographs in patients referred for suspected angina

Abstract Background The chest radiograph (CXR) is a well-established and broadly used first line diagnostic tool in patients with suspected cardiac conditions. In previous literature, artificial intelligence (AI) based interpretation of CXR has been shown to predict follow-up mortality of patients screened for neoplastic disease. Purpose In this context, we summarize our experience with the training, testing, and validating (internally and externally) of a deep learning (DL) model purposefully designed for predicting, from a single projection (posteroanterior/anteroposterior) CXR, long-term mortality of patients referred for angina and suspected coronary artery disease (CAD). Methods Demographic, clinical, and follow-up data of patients referred for angina to our institution (located in southern Europe) and undergoing coronary angiography were analyzed retrospectively. A deep convolutional neural network (DCNN) was designed to predict follow-up mortality from CXRs. External validation was performed on patients referred to a different medical Institution (located in north-western Europe). Results 6031 was randomly divided for model training (70%; n=4259) and model fine-tuning/model validation (10%; n=602). Internal clinical validation (model testing) was performed with the remaining patients (20%; n=1170). Patients were stratified according to AI-based interpretation quartiles (DCNN-CXR risk score). Median follow-up was 6.1 years (IQR 3.3 – 8.7) with a Kaplan-Meier (KM) overall estimated mortality of 21.9% (CI 19.2%-24.5%). Estimated mortality increased significantly according to the DCNN-CXR risk score (Low-risk 5%, Moderate 17%, High 29%, Very High 46%; p<0.0001) (figure 1-A). At Cox regression, the AI-derived CXR-score was the strongest predictor of follow-up mortality (p<0.005; OR: 3.16; CI: 2.47-3.85) and had an AUC of 0.793 (95% AUC CI: 0.759-0.827, Sens. 78%, Spec. 0.68%), that was significantly better than that achieved when using coronary angiography findings (AUC: 0.569, 95% CI: 0.526-0.611) (p<0.001) and age (AUC 0.735, 95% CI: 0.694-0.776) (p<0.004) as predictors (figure 1-B). The DCNN-CXR mortality prediction model improved when age and CAD status at the referral time were included (AUC 0.81; CI: 0.775-0.843). Preliminary results on external validation confirmed the DCNN-CXR-risk prediction performance (AUC 0.712 CI: 0.495-0.928; Sens 0.838; Spec 0.338). Conclusion Our DCNN model predicted, from a CXR, long-term overall mortality of patients with suspected angina pectoris referred for coronary angiography. The performance has been confirmed at internal and external validation, on patients in a different European country. The DCNN CXR-risk score could stratify long-term mortality risk better than any other risk factor, including CAD presence and degree. These findings may be used to optimize screening and prevention actions for this very comorbid group of patients.

Diagnostic accuracy of diastolic pressure ratio using a pressure microcatheter for intracoronary physiological assessment.

Recently, instantaneous wave-free ratio (iFR)has emerged as an alternative to the fractional flow reserve (FFR) for intracoronary physiological assessment. Although all diastolic resting indices are reportedly identical to the iFR, limited data exist on diastolic pressure ratio (dPR) measured using a microcatheter (dPRmicro). This study aimed to evaluate the diagnostic accuracy of dPRmicro compared to FFR measured using a microcatheter (FFRmicro) in real-world practice for intracoronary physiological assessment. This was a single-center, retrospective, observational study. We identified 103 consecutive suspected angina pectoris patients (107 lesions) who underwent dPRmicro and FFRmicro measurement using the Navvus® catheter at Takasaki Heart Hospital from March 2019 to June 2019. A total of 103 lesions in 103 patients were finally included in the study. The mean FFRmicro and dPRmicro values were 0.80 and 0.88, respectively. With an FFRmicro ≤ 0.80, the dPRmicro showed a diagnostic accuracy of 79.6%, sensitivity of 74.6%, specificity of 87.5%, positive predictive value of 90.4%, and negative predictive value of 68.6%. The area under the receiver operating characteristic (ROC) curve was 0.894 (95% confidence interval, 0.833-0.956), and the optimal cut-off value for dPRmicro derived from the ROC analysis was 0.90. dPRmicro and FFRmicro values were discordant in 21/103 cases (20.4%). As a multivariable logistic regression analysis was performed, the male sex (vs. female) had a statistically significant association with a dPRmicro-FFRmicro discordance (OR 4.91; 95% CI, 1.04-23.0; P = 0.044). No other factors were found to be significantly associated with the discordance. In conclusion, dPRmicro measured using a microcatheter had good diagnostic accuracy and correlation with FFRmicro, hence, it can be useful for making revascularization decisions. However, re-studies in larger populations will be needed to better understand the properties of diastolic resting index measured using a microcatheter in clinical settings.

Association of resting left ventricular global longitudinal strain with myocardial perfusion abnormalities evaluated by 13 N-ammonia positron emission tomography in patients with stable angina pectoris and normal left ventricular ejection fraction.

Little is known about whether resting left ventricular global longitudinal strain (GLS) impairment is associated with myocardial perfusion abnormalities evaluated using 13 N-ammonia positron emission tomography (13 N-NH3 -PET)-myocardial perfusion imaging (MPI). This study aimed to investigate the correlation between resting GLS and myocardial perfusion parameters in patients with a normal left ventricular ejection fraction (LVEF). We evaluated whether resting GLS can predict myocardial perfusion abnormalities in these patients. We selected 157 patients with suspected stable angina pectoris who underwent both ATP-stress NH3 -PET-MPI and 2-dimentional speckle tracing echocardiography. All subjects had a preserved LVEF and no known history of myocardial infarction. Patients were stratified into Group N (normal perfusion; summed stress score [SSS], 0-3; n=101), Group M (mildly to moderately abnormal perfusion; SSS, 4-11; n=41), or Group S (severely abnormal perfusion; SSS, 12+; n=15). GLS was more impaired as myocardial perfusion abnormality severity increased (-17.9±2.9% for Group N, -16.8±3.1% for Group M, and -14.2±3.5% for Group S; p<.001). GLS was weakly but significantly correlated with SSS (R=.32, p<.001), summed difference score (R=.32, p<.001), and myocardial blood flow during stress (R=-0.27, p<.001). Multivariate logistic regression analysis showed that male sex, diabetes mellitus, systolic blood pressure, and GLS were independent predictors of myocardial perfusion abnormality defined as Groups M and S. Additionally, the area under the curve for GLS for detecting myocardial perfusion abnormality was .65, and the optimal cutoff value for GLS was -16.5%, with sensitivity and specificity of 59% and 66%, respectively. In patients with suspected angina pectoris, resting GLS impairment despite a normal LVEF might aid the detection of hemodynamically significant coronary artery disease.

Clinical significance of epicardial fat in suspected angina pectoris: an observational study

Abstract Funding Acknowledgements Type of funding sources: None. Background Epicardial adipose tissue (EAT) is the visceral fat between pericardium and visceral epicardium and is the source of several endocrine and inflammatory mediators. It also has paracrine affects in the neighboring coronary arteries. Objective To evaluate the association of EAT with subclinical atherosclerosis (carotid intima media thickness &amp; flow mediated vasodilation), ultrasonic and anthropometric measures of abdominal fat, metabolic syndrome and coronary artery disease (CAD) concurrently. Material and methods Patients who underwent computed tomography (CT) coronary angiography for suspected CAD were prospectively included. All underwent anthropometric measurements, laboratory investigations, ultrasonic measurement of liver fat grade &amp; B-mode hepatorenal ratio, carotid intima media thickness (CIMT), flow mediated vasodilation (FMD), CT measurement of epicardial fat thickness (EFT) &amp; epicardial fat volume (EFV) along with CT coronary angiography. Study population was divided into 2 groups on the basis of presence or absence of CAD and were compared. The relationship between risk factors and presence of CAD was assessed by logistic regression analysis. To define EFT and EFV value predictive of the presence of significant CAD, the area under (AUC) the receiver operating characteristic (ROC) curve was calculated. Correlation between EFT as well as EFV with anthropometric and laboratory parameters, CIMT and FMD were assessed by Pearson correlation coefficient. Results Total 54 patients were included in study. Mean age was 54 years, 66% were diabetic and 33% were hypertensive. Mean CIMT, FMD, EFT and EFV were 0.70 + 0.27 cm; 5.64 + 2.64%; 5.51 + 2.50 mm and 60.6 + 28.6 cc, respectively. Total 34 (62.96%) patients were detected to have CAD. EFT as well as EFV were significantly higher in CAD group (3.31 + 2.34 vs 6.24 + 1.91mm; p= &amp;lt;0.001, 72.5 + 22.3 vs 40.4 + 27.1cc; p= &amp;lt;0.001); in patients with metabolic syndrome (83.3 + 18.4 vs 49.2 + 26.1cc; p &amp;lt; 0.001, 7.13 + 1.49 vs 4.16 + 2.32mm; p &amp;lt; 0.001). Both, EFV &amp; EFT were significantly correlated with the abdominal fat, CIMT and FMD. Smoking, age and EFV were the independent predictors for CAD. EFV &amp;gt;31.65cc predicted the presence of CAD (sensitivity 91.25%, specificity 60%, AUC = 0.798, 95% CI = 0.665-0.930) and EFT &amp;gt;2.85mm predicted the presence of CAD (sensitivity 94.1%, specificity 65%, AUC= 0.820, 95% CI= 0.687-0.953). Conclusions Epicardial fat is significantly associated with presence of CAD, metabolic syndrome, visceral fat, CIMT and FMD. CT measured epicardial fat may be included with CT based CAD lesion assessment and CT coronary calcium score to screen the patients of suspected angina pectoris. Abstract Figure. Epicardial adipose tissue Abstract Figure. EFV and CAD

Optimized Reconstruction Algorithm-Processed CT Image in the Diagnosis of Correlation between Epicardial Fat Volume and Coronary Heart Disease

This study was to analyze the application value of a reconstruction algorithm in CT images of patients with coronary heart disease and analyze the correlation between epicardial fat volume and coronary heart disease. An optimized reconstruction algorithm was constructed based on compressed sensing theory in this study. Then, the optimized algorithm was applied to the image reconstruction of multislice spiral CT image data after testing its sensitivity, accuracy, and specificity. 60 patients with suspected angina pectoris were divided into lesion group (40 cases) and normal group (20 cases) according to whether there were coronary atherosclerotic plaques in cardiac vessels. The results showed that the sensitivity, specificity, and accuracy of the optimized reconstruction algorithm were 91.78%, 84.27%, and 95.32%, and the running time was (12.18 ± 2.49) s. The CT value of the liver and the CT ratio of the liver and spleen in the lesion group were (53.81 ± 5.91) and (3.88 ± 0.67), respectively. There was no significant difference between the two groups ( P &gt; 0.05 ). The body mass index and epicardial fat volume in the lesion group were (31.93 ± 4.54) kg/m2 and (120.09 ± 22.01) cm3, respectively. The body mass index and fat volume in the lesion group were significantly higher than those in the normal group ( P &lt; 0.05 ). The epicardial fat constitution increased with the increase of the number of coronary arteries involved, and there was a positive correlation between them. Among patients with different coronary atherosclerotic plaques, the epicardial fat volume in patients with mixed plaques was the largest ( P &lt; 0.05 ). In summary, optimizing CT images under compressed a sensing reconstruction algorithm could effectively improve the diagnostic accuracy of doctors. Epicardial fat volume was positively correlated with coronary heart disease. Epicardial fat volume could be used as one of the important indexes to predict coronary heart disease.

Outcomes in patients with a first episode of chest pain undergoing early coronary CT imaging

ObjectivesTo investigate the impact of a CT-first strategy on all-cause and cardiovascular mortality in patients presenting with chest pain in outpatient cardiology clinics.MethodsPatients with a first presentation of suspected angina...

P18 The utility and validity of intracoronary administration of nicorandil alone for the measurement of fractional flow reserve in patients with intermediate coronary stenosis

Abstract Backgrand Recently, intracoronary nicorandil (ICN) administration in addition to intravenous adenosine 5"-triphosphate (IVATP) is generally used to achieve maximal hyperemia for evaluating fractional flow reserve (FFR). This study investigated the usefulness and safety of ICN alone compared with IVATP and ICN during IVATP for the achievement of maximal hyperemia in patients with suspected angina pectoris. Methods Two-hundred-ten angiographically intermediate lesions in two-hundred-seven patients who underwent FFR assessments were enrolled. FFR was measured after ICN (2mg/5seconds), IVATP (150µg/kg/min) for 2 minutes, IVATP (210µg/km/min) for 2 minutes, and ICN (2mg/5seconds) during IVATP (150µg/kg/min). Maximal hyperemia was defined as the lowest FFR measured among each method. Results During the protocol, 92% of patients achieved maximal hyperemia with ICN2mg, 54% with IVATP 150µg/kg/min, 91% with IVATP 210µg/kg/min, and 99% with ICN2mg during IVATP 150µg/kg/min, respectively. The FFR obtained with ICN2mg were strongly correlated with those obtained with ICN2mg during IVATP150µg/kg/min (r²=0.93, P&amp;lt; 0.001). The mean aortic pressure drop during hyperemia was significantly lower in ICN2mg than in IVATP 150µg/kg/min, IVATP 210µg/kg/min, and ICN2mg during IVATP 150µg/kg/min(9 ± 10, 11 ± 14, 24 ± 17, and 27 ± 19mmHg, p &amp;lt; 0.001, respectively). Despite no side effects reported during hyperemia with ICN2mg alone, transient atrioventricular block was observed in 1(1%) patient with IVATP 150µg/kg/min and 9(4%) patients with IVATP 210µg/kg/min. Also, 20 (10%) patients with IVATP 150µg/kg/min and 56(27%) with IVATP210µg/kg/min experienced chest discomfort during hyperemia. Conclusions The intracoronary administration of NIC2mg is safe and well tolerated, and shortens the procedure. Furthermore, intracoronary NIC2mg produced a more pronounced hyperemia than IVATP and may be the preferred mode of application for the assessment of FFR.

Analysis of elective coronary angiography findings in patients with suspected angina pectoris in the cardiocenter Hradec Králové – Real-life clinical practice in light of the guidelines

IntroductionCoronary angiography (CA) is a gold standard of diagnosis of occlusive coronary atherosclerosis in patients with high pre-test probability of IHD (PTP) and in patients with medium pre-test probability, in whom a prognostically significant ischemia was detected during a stress test. The imaging stress tests are preferred to the stress electrocardiogram due to higher sensitivity and specificity. The aim of this work was to analyze the profile of patients undergoing the elective CA due to suspected IHD. Study population and methodsPopulation of 184 patients who underwent elective CA due to suspected ischemic heart disease between April and August 2016 was retrospectively analyzed in the cardiocenter at the University Hospital Hradec Králové. The patient risk profile and use of cardiac stress tests and their relation to the CA findings were evaluated. The CA result was evaluated as positive if stenosis of coronary artery of ≥50% in at least one of the main coronary arteries was found. ResultsPatients with medium PTP prevailed in our study population – 154 (84%), there were 6 (3%) patients with low and 24 (13%) with high PTP. 112 (61%) patients had negative and 72 (39%) positive CA finding. Stress test was performed in 43 cases (23%) and the stress electrocardiograms predominated significantly over the imaging stress tests: 37 (86%) versus 6 (14%). In the medium-risk group, a stress test was performed in 36 (23%) patients, in 92% it consisted of stress electrocardiogram. None of the patients with low PTP had positive CA, in the medium-risk group the CA was positive in 38% and in the high-risk group in 54%. In the patients with positive exercise electrocardiogram, the CA was positive only in 10% of cases. 44% of patients with positive and 39% of patients with negative CA had typical angina pectoris. ConclusionMost of the patients referred for elective CA had medium risk of IHD. The patient medical history alone was not a reliable predictor of IHD. The stress tests for detection of ischemia were performed scarcely with the dominance of stress electrocardiogram, which was not reliable in the ischemia detection in the clinical practice. The imaging stress tests were not used to a sufficient extent and the rate of negative elective CAs was high in the analyzed study population.

Diabetes mellitus and heart failure: insights from a toxic relationship

Diabetes mellitus and heart failure: insights from a toxic relationship

Association between brain-derived neurotrophic factor and von Willebrand factor levels in patients with stable coronary artery disease

BackgroundBrain-derived neurotrophic factor (BDNF) is a neurotrophin involved in angiogenesis and maintenance of endothelial integrity. Whether circulating BDNF levels are associated with von Willebrand factor (vWF) levels, which are indicators of endothelial dysfunction is not known. This study investigated the association between plasma BNDF and vWF levels and whether these biomarkers could predict cardiovascular events at a 12-month follow-up in patients with stable coronary artery disease (CAD).MethodsWe recruited 234 patients with suspected angina pectoris. Subjects were divided into CAD (n = 143) and control (n = 91) groups based on coronary angiography. Plasma BDNF and vWF levels were measured using ELISA. Patients were followed-up for one year, and information on adverse cardiac events was collected.ResultsCAD patients exhibited significantly lower plasma BDNF and higher vWF levels than those of control patients. High vWF levels were associated with low BDNF levels even after adjustment for age, gender, low-density lipoprotein (LDL) levels, and the presence of diabetes mellitus. A receiver operating characteristic curve was used to determine whether low BDNF and high vWF levels could predict adverse cardiovascular events. The area under the curve for vWF and the inverse of BDNF were 0.774 and 0.804, respectively.ConclusionsThese findings suggest that endothelial dysfunction is an important determinant of the impaired circulating BDNF levels, and they further reflected cardiovascular prognosis in stable CAD patients.

High-Sensitivity Cardiac Troponin I and the Diagnosis of Coronary Artery Disease in Patients With Suspected Angina Pectoris.

We determined whether high-sensitivity cardiac troponin I can improve the estimation of the pretest probability for obstructive coronary artery disease (CAD) in patients with suspected stable angina. In a prespecified substudy of the SCOT-HEART trial (Scottish Computed Tomography of the Heart), plasma cardiac troponin was measured using a high-sensitivity single-molecule counting assay in 943 adults with suspected stable angina who had undergone coronary computed tomographic angiography. Rates of obstructive CAD were compared with the pretest probability determined by the CAD Consortium risk model with and without cardiac troponin concentrations. External validation was undertaken in an independent study population from Denmark comprising 487 patients with suspected stable angina. Higher cardiac troponin concentrations were associated with obstructive CAD with a 5-fold increase across quintiles (9%-48%; P<0.001) independent of known cardiovascular risk factors (odds ratio, 1.35; 95% confidence interval, 1.25-1.46 per doubling of troponin). Cardiac troponin concentrations improved the discrimination and calibration of the CAD Consortium model for identifying obstructive CAD (C statistic, 0.788-0.800; P=0.004; χ2=16.8 [P=0.032] to 14.3 [P=0.074]). The updated model also improved classification of the American College of Cardiology/American Heart Association pretest probability risk categories (net reclassification improvement, 0.062; 95% confidence interval, 0.035-0.089). The revised model achieved similar improvements in discrimination and calibration when applied in the external validation cohort. High-sensitivity cardiac troponin I concentration is an independent predictor of obstructive CAD in patients with suspected stable angina. Use of this test may improve the selection of patients for further investigation and treatment. URL: https://www.clinicaltrials.gov. Unique identifier: NCT01149590.

Absence of adventitial vasa vasorum formation at the coronary segment with myocardial bridge - An optical coherence tomography study.

Myocardial bridge (MB) is a myocardial bundle through which coronary segment tunnels and could compress coronary arteries causing myocardial ischemia. However, the characteristic structural findings of MB remain to be fully elucidated. Recently, we demonstrated that optical coherence tomography (OCT) enables us to visualize adventitial vasa vasorum (VV) formation in humans. In this study, we examined adventitial VV formation at the coronary segment with MB in humans using OCT. We examined 15 consecutive patients with suspected angina pectoris and MB in the left anterior descending (LAD) coronary arteries but no angiographic coronary stenosis. MB was detected on coronary angiography as a segment with milking effect. We performed intracoronary OCT imaging along the entire LAD. Morphometric analysis was performed at MB and proximal/distal segments at every 1mm. OCT examination showed the absence of adventitial VV formation at MB in the LAD, while VV was clearly noted at both the proximal and distal reference segments. Adventitial VV area was significantly less at MB compared with the proximal or distal references. These results with OCT imaging indicate that coronary segments with MB lack adventitial VV formation in humans, suggesting that MB could influence morphological and functional changes of the coronary artery.

Fractional flow reserve: a clinical perspective

Fractional flow reserve (FFR) is a reference invasive diagnostic test to assess the physiological significance of an epicardial coronary artery stenosis. FFR-guided percutaneous coronary intervention in stable coronary artery disease has been assessed in three seminal clinical trials and the indications for FFR assessment are expanding into other clinical scenarios. In this article we review the theoretical, experimental and clinical basis for FFR measurement. We place FFR measurement in the context of the comprehensive invasive assessment of coronary physiology in patients presenting with known or suspected angina pectoris in daily clinical practice, and review the recent developments in FFR assessment.

90 Head-to-head comparison shows poor performance of both diamond-forrester and pryor models in predicting coronary artery disease in chest pain patients: a single centre experience in a large cohort of patients

BackgroundAn optimal investigation strategy for patients with suspected angina pectoris (AP) remains elusive. UK and ESC guidelines use historical prediction models to guide management after the likelihood of coronary artery...

Symptoms and quality of life in patients with suspected angina undergoing CT coronary angiography: a randomised controlled trial

BackgroundIn patients with suspected angina pectoris, CT coronary angiography (CTCA) clarifies the diagnosis, directs appropriate investigations and therapies, and reduces clinical events. The effect on patient symptoms is currently unknown.MethodsIn...

High-Sensitivity Cardiac Troponin I and the Diagnosis of Coronary Artery Disease in Patients with Suspected Angina Pectoris

High-Sensitivity Cardiac Troponin I and the Diagnosis of Coronary Artery Disease in Patients with Suspected Angina Pectoris

Coronary CT Angiography as a Diagnostic and Prognostic Tool: Perspectives from the SCOT-HEART Trial.

Coronary artery disease is the leading cause of death worldwide. Many trials to date have investigated the diagnostic accuracy of coronary computed tomography angiography (CCTA) when compared to the gold standard diagnostic test, invasive coronary angiography. However, whether the use of a non-invasive anatomical test, such as CCTA, can translate into improved patient risk stratification, management and outcome has yet to be established. The Scottish COmputed Tomography of the HEART (SCOT-HEART) trial sought to address these questions and determined whether CCTA, when used in addition to standard care, could aid the diagnosis, further investigation and treatment of patients referred to the cardiology clinic with suspected angina due to coronary heart disease. In this trial, CCTA clarified the diagnosis of angina due to coronary heart disease in a quarter of patients and this led to major alterations in treatment and management that appeared to reduce the risk of subsequent coronary heart disease death or non-fatal myocardial infarction. The SCOT-Heart trial has established that CCTA is a valuable diagnostic test in patients with suspected angina pectoris due to coronary heart disease and leads to greater clarity, more focused appropriate treatments and better coronary heart disease outcomes.

Serial Changes in High-Sensitivity Cardiac Troponin, N-terminal Pro–B-Type Natriuretic Peptide, and Heart Fatty Acid Binding Protein during Exercise Echocardiography in Patients with Suspected Angina Pectoris and Normal Resting Left Ventricular Function

To the Editor: Cardiac troponin is the standard biomarker for detection of myocardial injury. An increase of cardiac troponin >99th percentile by use of a sufficiently sensitive and precise assay is required to diagnose acute myocardial infarction (MI)1 and is increasingly measured by use of high-sensitivity cardiac troponin T (hs-cTnT) and hs-cTnI assays outside the US. In patients with stable coronary artery disease (SCAD), hs-cTnT can be detected in >80% of patients (1), with values above the 99th percentile in approximately 11% of patients (2). Increasing concentrations of hs-cTnT and hs-cTnI above the 99th percentile are also associated with an increased risk of adverse cardiovascular events (2, 3). The mechanisms underlying cardiac troponin increase remain unclear, but may include silent plaque rupture, inducible ischemia, anatomic burden of CAD, cardiac structural abnormalities, or impaired left ventricular (LV) function (4, 5). We evaluated serial changes in hs-cTnT (Elecsys 2010, Roche Diagnostics, detection limit 3 ng/L, 10% CV 13.5 ng/L, 99th percentile value of 14 ng/L) (6), sensitive cTnI, (S-cTnI) (TnI Ultra, Advia Centaur, Siemens Healthcare Diagnostics, detection limit 0.006 μg/L, 10% CV 0.045 μg/L, level 2 assay) (7, 8), heart fatty acid binding protein (HFABP) (Evidence Investigator, Randox Laboratories, 99th percentile 5.8 μg/L, CV 5%) (9), and N-terminal pro–B-type natriuretic peptide (NT-pro-BNP) (Elecsys 2010, Roche Diagnostics, CV 3.2%–2.4% 175–4962 ng/L with an analytic range 5–35 000 ng/L) (10) in outpatients referred for exercise echocardiography with suspected angina pectoris and normal resting LV function (ejection fraction >50%) without overt cardiac structural abnormality. Blood …

Value of resting echocardiographic findings and dobutamine stress echocardiography for diagnosing myocardial ischemia in patients with suspected angina pectoris.

We evaluated the diagnostic value of resting echocardiographic findings including total heart calcification (THC) score in combination with dobutamine stress echocardiography (DSE) for detection of myocardial ischemia. Altogether, 110 patients with suspected angina pectoris underwent resting echocardiography and DSE. On the basis of resting echocardiography, we determined the THC score, left anterior descending artery diastole-to-systole velocity ratio (LAD-DSVR), and positive myocardial velocity during isovolumic relaxation phase (VIVR ) detected by color-coded tissue Doppler imaging. Myocardial ischemia was diagnosed by a 25% or greater reduction in the internal diameter of major coronary vessels with impaired fractional flow reserve (FFR ≤0.80). DSE had excellent specificity (89%) but modest sensitivity (52%) for wall-motion abnormality (WMA) analysis. Multivariate analysis showed that THC score ≥2 (odds ratio and 95% confidence interval: 4.49 [2.29-10.6]; P=0.018), LAD-DSVR ≤1.5 (6.43 [1.39-20.3], P=0.019), and duration of positive VIVR ≥71msec (7.93 [3.72-12.1]; P<0.001) were independent predictors of ischemia. The combination of inducible WMA and THC score yielded significantly higher sensitivity for ischemia detection than the inducible WMA alone (80% vs. 52%, P=0.0008). Using receiver operating characteristics analyses, adding all three resting echocardiographic findings to clinical variables plus inducible WMA further improved prediction of ischemia (P=0.028). Integration of DSE and resting echocardiographic findings describing degree of heart calcification, impaired LAD flow, and extent of delayed ejection motion of the myocardium improves detection of coronary angiogram-based FFR-guided ischemia.