Electronic Spectra of C60 Films Using Screened Range Separated Hybrid Functionals.

We study computationally the electronic spectra of C60 thin films using the recently developed density functional theory (DFT) framework combining a screened range separated hybrid (SRSH) functional with a polarizable continuum model (PCM). The SRSH-PCM approach achieves excellent correspondence between the frontier orbital's energy levels and the ionization potential and electron affinity of the molecular system at the condensed phase and consequently leads to high quality electronic excitation energies when used in time-dependent DFT calculations. Our calculated excited states reproduce the experimentally main reported spectral peaks at the 3.6-4.6 eV energy range and when addressing excitonic effects also reproduce the red-shifted spectral feature. Notably, we analyze the low-lying peak at 2.7 eV and associate it to an excitonic state.

CTRAMER: An open-source software package for correlating interfacial charge transfer rate constants with donor/acceptor geometries in organic photovoltaic materials.

In this paper, we present CTRAMER (Charge-Transfer RAtes from Molecular dynamics, Electronic structure, and Rate theory)-an open-source software package for calculating interfacial charge-transfer (CT) rate constants in organic photovoltaic (OPV) materials based on ab initio calculations and molecular dynamics simulations. The software is based on identifying representative donor/acceptor geometries within interfacial structures obtained from molecular dynamics simulation of donor/acceptor blends and calculating the corresponding Fermi's golden rule CT rate constants within the framework of the linearized-semiclassical approximation. While the methods used are well established, the integration of these state-of-the-art tools originating from different disciplines to study photoinduced CT processes with explicit treatment of the environment, in our opinion, makes this package unique and innovative. The software also provides tools for investigating other observables of interest. After outlining the features and implementation details, the usage and performance of the software are demonstrated with results from an example OPV system.

Photoinduced charge transfer in Zn(II) and Au(III)-ligated symmetric and asymmetric bacteriochlorin dyads: A computational study.

The excited-state properties and photoinduced charge-transfer (CT) kinetics in a series of symmetrical and asymmetrical Zn- and Au-ligated meso-meso-connected bacteriochlorin (BChl) complexes are studied computationally. BChl derivatives, which are excellent near-IR absorbing chromophores, are found to play a central role in bacterial photosynthetic reaction centers but are rarely used in artificial solar energy harvesting systems. The optical properties of chemically linked BChl complexes can be tuned by varying the linking group and involving different ligated metal ions. We investigate charge transfer in BChl dyads that are either directly linked or through a phenylene ring (1,4-phenylene) and which are ligating Zn or Au ions. The directly linked dyads with a nearly perpendicular arrangement of the BChl units bear markedly different properties than phenylene linked dyads. In addition, we find that the dielectric dependence of the intramolecular CT rate is very strong in neutral Zn-ligated dyads, whereas cationic Au-ligated dyads show negligible dielectric dependence of the CT rate. Rate constants of the photo induced CT process are calculated at the semiclassical Marcus level and are compared to fully quantum mechanical Fermi's golden rule based values. The rates are calculated using a screened range separated hybrid functional that offers a consistent framework for addressing environment polarization. We study solvated systems in two solvents of a low and a high scalar dielectric constant.

Cardiac Computed Tomography versus Echocardiography in the Assessment of Stenotic Rheumatic Mitral Valve.

PURPOSE: There are different clinical cardiac applications of dual source computed tomography (DSCT). Here, we aimed to compare the DSCT with the transthoracic echocardiography (TTE) for evaluating the Wilkins score and planimetric mitral valve area (MVA) of a rheumatic stenotic mitral valve. MATERIALS AND METHODS: We prospectively evaluated mitral valvular structure and function in 31 patients with known mitral stenosis undergoing electrocardiogram-gated, second-generation DSCT, in our heart center for different indications. Mitral valve was evaluated using Wilkins score, and also, the planimetric MVA was assessed. RESULTS: We found a significant difference between MVAs determined by DSCT (average 1.42 ± 0.44 cm2) and MVAs determined by TTE (average 1.35 ± 0.43 cm2 ; difference 0.07 ± 0.16 cm2; P = 0.018). Linear regression analysis revealed a good correlation between the two techniques (r = 0.934; P < 0.0001). The limits of agreement for DSCT and TTE in the Bland-Altman analysis were ±0.31 cm2 . DSCT using TTE as the reference enabled good discrimination between mild and moderate-to-severe stenosis and had an area under the ROC curve of 0.967 (CI 0.912-1.023; P < 0.0001). Wilkins scores obtained by DSCT (7.51 ± 1.17, range 5-10) and TTE (8.16 ± 1.27, range 6-10) had a moderate correlation (r = 0.686; P < 0.0001). CONCLUSION: We found that planimetric MVA measurements assessed by DSCT were closely correlated with MVA calculations by TTE. The moderate correlation was observed for the Wilkins score.

The assessment of relationship between fragmented QRS complex and left ventricular wall motion score index in patients with ST elevation myocardial infarction who underwent primary percutaneous coronary intervention.

OBJECTIVES: Fragmented QRS (fQRS) has been found to be associated with high mortality and arrhythmic events in acute coronary syndromes. Regional systolic function using wall motion score index (WMSI) is an alternative to left ventricular ejection fraction (LVEF) for the assessment of left ventricular systolic function. The aim of this study was to investigate the relation between the presence of fQRS on admission electrocardiogram (ECG) and WMSI in ST elevation myocardial infarction (STEMI) underwent primary coronary intervention (PCI). The in-hospital and long-term prognostic significance of persistent fQRS was also evaluated. METHODS: In this retrospective study, 542 patients with a diagnose of STEMI underwent primary PCI were included. Study patients were divided into two groups according to the presence (n = 153) or absence (n = 389) of a fQRS on admission ECG. RESULTS: WMSI was found to be significantly higher in fQRS(+) group compared to the fQRS(-) group (P < 0.001). In multivariete analysis, WMSI was found to be an independent predictor of fQRS, and fQRS was inversely associated with LVEF. The in-hospital reinfarction (P = 0.003), MACE (P = 0.024), intraaortic balloon pump use (P = 0.014), and advanced heart failure (P < 0.001) were found to be significantly more frequent in the fQRS(+) group. The presence of fQRS on admission was found to be associated with an increase in long-term cardiovascular mortality (P = 0.028), and long-term all-cause mortality (P = 0.022). CONCLUSION: WMSI was significantly related with the presence of the fQRS, which reflects the linking between impairment of regional left ventricular systolic function and the presence of severe myocardial injury in STEMI.

Antioxidative Triplet Excitation Energy Transfer in Bacterial Reaction Center Using a Screened Range Separated Hybrid Functional.

Excess energy absorbed by photosystems (PSs) can result in photoinduced oxidative damage. Transfer of such energy within the core pigments of the reaction center in the form of triplet excitation is important in regulating and preserving the functionality of PSs. In the bacterial reaction center (BRC), the special pair (P) is understood to act as the electron donor in a photoinduced charge transfer process, triggering the charge separation process through the photoactive branch A pigments that experience a higher polarizing environment. At this work, triplet excitation energy transfer (TEET) in BRC is studied using a computational perspective to gain insights into the roles of the dielectric environment and interpigment orientations. We find in agreement with experimental observations that TEET proceeds through branch B. The TEET process toward branch B pigment is found to be significantly faster than the hypothetical process proceeding through branch A pigments with ps and ms time scales, respectively. Our calculations find that conformational differences play a major role in this branch asymmetry in TEET, where the dielectric environment asymmetry plays only a secondary role in directing the TEET to proceed through branch B. We also address TEET processes asserting the role of carotenoid as the final triplet energy acceptor and in a mutant form, where the branch pigments adjacent to P are replaced by bacteriopheophytins. The necessary electronic excitation energies and electronic state couplings are calculated by the recently developed polarization-consistent framework combining a screened range-separated hybrid functional and a polarizable continuum mode. The polarization-consistent potential energy surfaces are used to parametrize the quantum mechanical approach, implementing Fermi's golden rule expression of the TEET rate calculations.

[Relation of heart-type fatty acid-binding protein with the degree and extent of atherosclerosis in patients with non-ST elevation acute coronary syndrome]. / ST segment yükselmesiz akut koroner sendromlu hastalarda kalp tipi yag asidi baglayici proteinin koroner arter hastaliginin yayginlik ve ciddiyeti ile iliskisi.

OBJECTIVES: The relationship between markers of myocardial ischemia and severity of coronary artery disease (CAD) has been investigated in several studies. In this study, we examined the relationship between severity of CAD and heart-type fatty acid-binding protein (H-FABP), a new marker of ischemia in patients with non-ST-segment elevation acute coronary syndrome (ACS). STUDY DESIGN: This prospective study comprised 49 patients who were referred to the emergency room with a diagnosis of non-ST elevation myocardial infarction. Troponins, creatine kinase-MB, lactate dehydrogenase, and aspartate aminotransferase levels were measured quantitatively, while blood H-FABP levels were measured qualitatively in the 4th-8th hour from the onset of symptoms. All patients underwent coronary angiography within 72 hours after admission. Clinical and coronary angiographic characteristics of patients with positive and negative values of H-FABP were compared. Gensini and SYNTAX scores were used to determine the severity of CAD. RESULTS: There were no statistically significant differences in mean age, gender distribution, risk factors for CAD, ischemic changes on ECG, or Gensini and SYNTAX scores between the H-FABP-negative and -positive groups (p>0.05). The duration of chest pain in the H-FABP-positive group was significantly longer than in the negative group (p<0.001). Troponin, CK-MB, and AST levels as well as thrombolysis in myocardial infarction (TIMI) risk scores were found to be significantly higher in the H-FABP-positive group (p<0.05). CONCLUSION: H-FABP is a useful marker for the diagnosis and risk evaluation of patients with non-ST elevation ACS. However, it is insufficient in evaluating the severity of CAD.

Mitral insufficiency caused by left atrial chordae.

We report an unusual case of moderate mitral regurgitation caused by abnormal insertion of chordae tendinea to the interatrial septum and tethering the middle scallop of the anterior mitral leaflet. This is an extremely rare congenital abnormality causing mitral regurgitation.

Role of Dielectric Screening in Calculating Excited States of Solvated Azobenzene: A Benchmark Study Comparing Quantum Embedding and Polarizable Continuum Model for Representing the Solvent.

The low energy excited states of the conformational isomers of solvated azobenzene are calculated with several DFT methods accounting for the solute-solvent interaction implicitly with the polarizable continuum model or explicitly with subsystem DFT. For the latter, embedding potentials are calculated for 21 sampled snapshots of the solvent molecules. First, we find that accounting for the solvent implicitly or explicitly has little effect on the predicted cis-trans S1 excitation energy gap. Second, we find that azobenzene's S1 cis and trans energies are accurate as long as a screened range-separated hybrid exchange-correlation functional is employed. Finally, we also tested a simplified workflow whereby a single, averaged, embedding potential is used. Unfortunately, we find larger deviations against the experiment for the simplified workflow. This highlights a basic flaw in the approach, where the time scale of solvent averaging is much longer than that of the solute's electronic polarization.

Coexistent Brugada syndrome and Wolff-Parkinson-White syndrome: what is the first clinical presentation?

The coexistence of Brugada syndrome and Wolff-Parkinson-White (WPW) syndrome is a very rare phenomenon. We describe a 31-year-old patient without any previous cardiac disorder admitted to our hospital due to palpitations and concomitantly diagnosed as WPW syndrome and treated with radiofrequency catheter ablation. He was later diagnosed with Brugada syndrome and followed-up 2 years without any symptoms. We discuss other previously reported cases in literature, in which these two conditions exist simultaneously.

The outcome of primary percutaneous coronary intervention for stent thrombosis causing ST-elevation myocardial infarction.

BACKGROUND: There are very few scientific data about the effectiveness of primary percutaneous coronary intervention (PCI) in patients with ST-elevation myocardial infarction (STEMI) due to stent thrombosis (ST). The purpose of the present study is to investigate the efficacy and outcome of primary PCI for STEMI due to ST in the largest consecutive patient population with ST reported to date. METHODS: A total of 2,644 consecutive STEMI patients undergoing primary PCI were retrospectively enrolled into the present study. The primary end point of this study was successful angiographic reperfusion defined as postprocedural Thrombolysis In Myocardial Infarction grade III flow. The secondary end points were cardiovascular death and reinfarction. RESULTS: Stent thrombosis was the cause of STEMI in 118 patients (4.4%). In patients with ST, angiographic success (postprocedural Thrombolysis In Myocardial Infarction grade III flow) was worse than in patients with de novo STEMI (76.3% vs 84.8%, P = .01). Patients with ST had significantly higher incidence of in-hospital cardiovascular mortality than patients with de novo STEMI (10.2% vs 5.3%, P = .02). In-hospital reinfarction rate was similar in both groups. In addition, long-term (mean 22 months) cardiovascular mortality and reinfarction rates were significantly higher in patients with ST compared with those without (17.4% vs 10.5%, P = .02 and 15.6% vs 9.5%, P = .03, respectively). CONCLUSIONS: Primary PCI for treatment of ST is less effective, and these patients are at increased risk for in-hospital and long-term mortality compared with patients undergoing primary PCI due to de novo STEMI.

Comparison of primary percutaneous coronary intervention and streptokinase for acute isolated inferior ST elevation myocardial infarction with a predicted low risk profile.

BACKGROUND: Primary percutaneous coronary intervention (PCI) is the treatment of choice for acute myocardial infarction, especially for high-risk patients, but the data for low-risk patients are conflicting. A very low-risk subgroup of acute inferior myocardial infarction can be identified by electrocardiographic and clinical criteria during admission. We aimed to compare the outcomes of primary PCI and streptokinase treatment in this subgroup, which has not been evaluated separately before. MATERIAL/METHODS: We retrospectively analyzed in-hospital and 10-month follow-up outcomes of 97 patients with inferior acute myocardial infarction and clinical and electrocardiographic criteria predicting low risk who have been treated with primary PCI or streptokinase. RESULTS: Forty-eight patients received streptokinase, and 49 had undergone primary PCI. Both during the in-hospital period and follow-up, the groups did not differ in the end points of death, reinfarction, or stroke (in-hospital: 2.1% versus 4.1%, P=.57; follow-up: 8.9% versus 8.9%, P=1.000). Length of hospital stay was longer in the streptokinase group (6.5+/-2.5 versus 9.1+/-3.7 days, P=.001). Rate of repeat revascularization was reduced in the PCI group at 10 months (28.9% versus 55.6%, P=.002). CONCLUSIONS: When streptokinase and primary PCI are compared in isolated inferior acute myocardial infarction patients with a low-risk profile, there are no differences for in-hospital and long-term rates of death, reinfarction, or stroke. Primary angioplasty reduces the length of initial hospital stay, and reduces repeat admissions by decreasing the need for subsequent revascularization procedures. Large-scale studies are needed to reach a final conclusion.

On the Role of the Special Pair in Photosystems as a Charge Transfer Rectifier.

The special pair, a bacteriochlorophyll a (BChl) dimer found at the core of bacterial reaction centers, is known to play a key role in the functionality of photosystems as a precursor to the photosynthesis process. In this paper, we analyze the inherent affinity of the special pair to rectify the intrapair photo-induced charge transfer (CT). In particular, we show that the molecular environment affects the nuclear geometry, resulting in symmetry breaking between the two possible intrapair CT processes. To this end, we study the relationships of the intrapair CT and the molecular geometry with respect to the effective dielectric constant provided by the molecular environment. We identify the special pair structural feature that breaks the symmetry between the two molecules, leading to CT rectification. Excited state energies, oscillator strengths, and electronic coupling values are obtained via time-dependent density functional theory, employing a recently developed framework based on a screened range-separated hybrid functional within a polarizable continuum model (SRSH-PCM). We analyze the rectification capability of the special pair by calculating the CT rates using a first-principles-based Fermi's golden rule approach.

How Well Does a Solvated Octa-acid Capsule Shield the Embedded Chromophore? A Computational Analysis Based on an Anisotropic Dielectric Continuum Model.

The optical properties of chromophores embedded in a water-solvated dimer of octa-acid that forms a molecular-shaped capsule are investigated. In particular, we address the anisotropic dielectric environment that appears to blue-shift excitation energies compared to the free aqueous chromophores. Recently we reported that using an effective scalar dielectric constant ε ≈ 3 appears to reproduce the measured spectra of the embedded coumarins, suggesting that the capsule provides a significant, albeit not perfect, screening of the aqueous dielectric environment. Here, we report absorption energies using a theoretical treatment that includes continuum solvation affected by an anisotropic dielectric function reflecting the high-dielectric environment outside of the capsule and the low-dielectric region within. We report time-dependent density functional theory calculations using a range-separated functional with the Poisson boundary conditions that model the anisotropic dielectric environment. Our calculations find that the anisotropic environment due to the water-solvated hydrophobic capsule is equivalent to a homogeneous effective dielectric constant of ≈3. The calculated values also appear to reproduce measured absorption of the embedded coumarin, where we study the effect of the hydrophobic capsule on the excited state.

On the Interplay between Electronic Structure and Polarizable Force Fields When Calculating Solution-Phase Charge-Transfer Rates.

We present a comprehensive analysis of the interplay between the choice of an electronic structure method and the effect of using polarizable force fields vs. nonpolarizable force fields when calculating solution-phase charge-transfer (CT) rates. The analysis is based on an integrative approach that combines inputs from electronic structure calculations and molecular dynamics simulations and is performed in the context of the carotenoid-porphyrin-C60 molecular triad dissolved in an explicit tetrahydrofuran (THF) liquid solvent. Marcus theory rate constants are calculated for the multiple CT processes that occur in this system based on either polarizable or nonpolarizable force fields, parameterized using density functional theory (DFT) with either the B3LYP or the Baer-Neuhauser-Livshits (BNL) density functionals. We find that the effect of switching from nonpolarizable to polarizable force fields on the CT rates is strongly dependent on the choice of the density functional. More specifically, the rate constants obtained using polarizable and nonpolarizable force fields differ significantly when B3LYP is used, while much smaller changes are observed when BNL is used. It is shown that this behavior can be traced back to the tendency of B3LYP to overstabilize CT states, thereby pushing the underlying electronic transitions to the deep inverted region, where even small changes in the force fields can lead to significant changes in the CT rate constants. Our results demonstrate the importance of combining polarizable force fields with an electronic structure method that can accurately capture the energies of excited CT states when calculating charge-transfer rates.

Explaining Spectral Asymmetries and Excitonic Characters of the Core Pigment Pairs in the Bacterial Reaction Center Using a Screened Range-Separated Hybrid Functional.

Spectral peaks of the special pair (P) and adjacent pigments in the bacterial reaction center (BRC) are investigated computationally. We employ a novel framework based on a polarization-consistent treatment of the dielectric environment, combining the polarizable continuum model (PCM) with time-dependent screened range-separated hybrid (SRSH) density functional theory. Our calculations quantitatively reproduce recently measured spectral peak splits between P excitonic states and spectral asymmetries within the pairs of excited states of the adjacent bacteriochlorophyll a (BChl) and bacteriopheophytin a (BPhe) pigments. For the special pair, a splitting energy between the absorptive state and a blue-shifted semidark state of 0.07 eV is found in close agreement with the measured value. The spectral asymmetries within the pseudosymmetric pairs of BChl and BPhe pigments are interpreted to result from locally different effective dielectric environments in the A and the B branch, where the latter are exposed to a lesser polarizing environment. We base our analysis on X-ray-resolved structures and where the effect of neighboring pigments on the electronic structure is addressed through an effective dielectric environment. We show that the spectral trends are only reproduced using a polarization-consistent framework based on a screened range-separated hybrid functional, whereas B3LYP-PCM energies fail to provide the correct trends.

Endothelial nitric oxide synthase gene (T-786C) polymorphism in patients with slow coronary flow.

OBJECTIVES: In this study, we aimed to investigate the relationship between T-786C polymorphism of the endothelial nitric oxide synthase (eNOS) gene and slow coronary flow (SCF). STUDY DESIGN: A total of 56 patients with SCF but otherwise normal coronary arteries (mean age 48+/-9 years) and 37 controls with normal coronary angiograms (mean age 50+/-12 years) were enrolled in the study. Screening for the eNOS T-786C polymorphism was performed by restriction fragment length polymorphism methodology. RESULTS: In normal coronary artery and SCF groups, TT genotype frequency was 23 (62.2%) versus 22 (39.3%), TC heterozygote genotype frequency was 11 (29.7%) versus 30 (53.6%), and CC homozygote genotype frequency was 3 (8.1%) versus 4 (7.1%), respectively (P=0.07). In dominant model statistical analysis, total CC and CT genotype frequency in control and study groups was found to be 14 (37.3%) versus 34 (60.7%), respectively (P=0.025). A positive correlation was found between the mean thrombolysis in myocardial infarction frame count and C allele in patients with SCF (r=0.21, P=0.043). CONCLUSION: We concluded that the T-786C polymorphism of eNOS gene might be a risk factor for the SCF.

Transthoracic Doppler echocardiographic coronary flow imaging in identification of left anterior descending coronary artery stenosis in patients with left bundle branch block.

BACKGROUND: Conventional noninvasive methods have well-known limitations for the detection of coronary artery disease (CAD) in patients with left bundle branch block (LBBB). However, advancements in Doppler echocardiography permit transthoracic imaging of coronary flow velocities (CFV) and measurement of coronary flow reserve (CFR). Our aim was to evaluate the diagnostic value of transthoracic CFR measurements for detection of significant left anterior descending (LAD) stenosis in patients with LBBB and compare it to that of myocardial perfusion scintigraphy (MPS). METHODS: Simultaneous transthoracic CFR measurements and MPS were analyzed in 44 consecutive patients with suspected CAD and permanent LBBB. Typical diastolic predominant phasic CFV Doppler spectra of distal LAD were obtained at rest and during a two-step (0.56-0.84 mg/kg) dipyridamole infusion protocol. CFR was defined as the ratio of peak hyperemic velocities to the baseline values. A reversible perfusion defect at LAD territory was accepted as a positive scintigraphy finding for significant LAD stenosis. A coronary angiography was performed within 5 days of the CFR studies. RESULTS: The hyperemic diastolic peak velocity (44 +/- 9 cm/sec vs 62 +/- 2 cm/sec; P=0.01) and diastolic CFR (1.38 +/- 0.17 vs 1.93 +/- 0.3; P=0.001) were significantly lower in patients with LAD stenosis compared to those without LAD stenosis. The diastolic CFR values of <1.6 yielded a sensitivity of 100% and a specificity of 94% in the identification of significant LAD stenosis. In comparison, MPS detected LAD stenosis with a sensitivity of 100% and a specificity of 29%. CONCLUSIONS: CFR measurement by transthoracic Doppler echocardiography is an accurate method that may improve noninvasive identification of LAD stenosis in patients with LBBB.

The relation between insulin resistance determined by homeostatic [corrected from haemostatic] modelling and slow coronary flow.

INTRODUCTION: In this study, we sought to determine whether insulin resistance, which is investigated by homeostatic modelling, is related to slow coronary flow (SCF). MATERIALS AND METHODS: A total of 24 patients with SCF (4 females/20 males, mean age 47 +/- 12 years) and 32 patients with normal coronary artery (10 females/22 males, mean age 52 +/- 12 years) were included in the study. Baseline glucose, insulin and plasma lipid levels were measured. A standard oral glucose tolerance test (OGTT) was performed and post-challenge insulin levels were also measured. The index of insulin resistance was calculated with the homeostatic modelling [homeostatic model assessment for insulin resistance index (HOMA-IR)]. RESULTS: There were no differences between the 2 groups with regard to age, lipid levels, blood pressure levels, history of smoking, fasting and post-challenge plasma glucose. Baseline insulin levels were augmented in the SCF group (9.64 +/- 5.93 vs 7.04 +/- 3.26, P = 0.041). HOMA-IR levels were not different between the study groups (2.20 +/- 1.44 vs 1.69 +/- 0.86, P = 0.129). Manifest insulin resistance was significantly higher in the CSF group as compared with the control group (25% vs 3%, P = 0.01). CONCLUSION: Manifest insulin resistance is seen more frequently in patients with SCF.

Clinical usefulness of epicardial adipose tissue in patients with high-intermediate pre-test probability for coronary artery disease.

BACKGROUND: Epicardial adipose tissue (EAT) is thought to be associated with the extension and severity of coronary artery disease (CAD), and echocardiographic measurement of EAT thickness is considered to be a possible cardiovascular risk indica-tor. The European Society of Cardiology Task Force recommends further non-invasive testing in patients with an intermediate pre-test probability (PTP) for the diagnosis of CAD. AIM: We sought to evaluate the clinical usefulness of performing EAT measurements in patients with a high-intermediate PTP. METHODS: Patients referred to an outpatient clinic with stable chest pain symptoms, with PTP for CAD between 66% and 85%, were included in the study. Echocardiographic measurement of the EAT was identified as the echo-free space between the outer wall of the myocardium and the visceral layer of the pericardium. Single-photon emission computed tomography (SPECT) was performed in all patients. The diagnosis of CAD was based on the presence of reversible perfusion defects on SPECT. RESULTS: A total of 126 patients (76 men, 60.3%) with a mean age of 65.3 ± 9.1 years were recruited. The EAT thickness was 7.3 ± 0.7 mm in patients with positive SPECT and 6.2 ± 0.6 mm in patients with negative SPECT (p < 0.001). Multivariable analysis revealed higher rates of positive SPECT in patients with higher EAT (odds ratio [OR] 9.80; 95% confidence interval [CI] 3.72-25.79; p < 0.001), and receiver operating characteristic curve analysis showed that the greatest specificity was obtained when the cut-off value of EAT thickness was 6.75 mm (sensitivity 76%; specificity 74%). CONCLUSIONS: In patients with high-intermediate PTP, EAT is a useful measurement that may assist in risk stratification.