Yeon-Hyeon Choe

Comparison of the coronary calcium score with the estimated coronary risk

ObjectivesThe role of coronary calcium scoring in coronary risk estimation is not well established. Calcium scoring could provide additional information in a certain subgroup of patients where the calcium score does not match the conventional Framingham risk estimates. We explored the characteristics of such a subgroup. MethodsThe study participants were 1653 asymptomatic persons who underwent routine health screening and calcium scoring using the 16-slice multidetector computed tomography. Risk stratification was performed in five categories both by 10-year Framingham coronary risk and the Agatston coronary calcium score. ResultsRisk stratifications by coronary calcium score and absolute risk showed a large discrepancy (difference ≥3 classes) in about 9% of participants. The proportion increased with age (P for trend <0.0001). An exploratory analysis revealed that age (partial R2=0.109, P<0.0001) and the presence of the metabolic syndrome (partial R2=0.025, P<0.001) were independent variables that accounted for the variance of the residual of regression between the log-transformed value of coronary calcium score and the absolute risk. ConclusionCalcium scoring may be clinically more useful in older (≥50 years) participants and/or in participants with the metabolic syndrome because of the relatively higher probability of obtaining additional information that the conventional Framingham risk estimation cannot provide.

Early detection of subclinical ventricular deterioration in aortic stenosis with cardiovascular magnetic resonance and echocardiography

BackgroundSevere aortic stenosis (AS) patients with late gadolinium enhancement (LGE) on cardiovascular magnetic resonance (CMR) or left ventricular (LV) systolic dysfunction are known to have worse outcome. We aimed to investigate whether LGE on CMR would be useful in early detection of subclinical LV structural and functional derangements in AS patients.Methods118 patients with moderate to severe AS were prospectively enrolled. Echocardiography and CMR images were taken and the patients were divided into groups according to the presence/absence of LGE and of LV systolic dysfunction (LV ejection fraction (EF) <50%). The stiffness of LV was calculated based on Doppler and CMR measurements.ResultsPatients were grouped into either group 1, no LGE and normal LVEF, group 2, LGE but normal LVEF and group 3, LGE with depressed LVEF. There was a significant trend towards increasing LV volumes, worsening of LV diastolic function (E/e’, diastolic elastance), systolic function (end-systolic elastance) and LV hypertrophy between the three groups, which coincided with worsening functional capacity (all p-value < 0.001 for trend). Also, significant differences in the above parameters were noted between group 1 and 2 (E/e’, 14.6 ± 4.3 (mean ± standard deviation) in group 1 vs. 18.2 ± 9.4 in group 2; end-systolic elastance, 3.24 ± 2.31 in group 1 vs. 2.38 ± 1.16 in group 2, all p-value < 0.05). The amount of myocardial fibrosis on CMR correlated with parameters of diastolic (diastolic elastance, Spearman’s ρ = 0.256, p-value = 0.005) and systolic function (end-systolic elastance, Spearman’s ρ = -0.359, p-value < 0.001).ConclusionsThese findings demonstrate the usefulness of CMR for early detection of subclinical LV structural and functional deterioration in AS patients.

Original ResearchEditorial CommentCMR Imaging for Diastolic Hemodynamic Assessment: Fantasy or Reality?⁎

Assessment of pericardial disease by cardiac magnetic resonance (CMR) is a well-established clinical application ([1][1]). For the diagnosis of constrictive pericarditis, CMR has focused on morphological features, specifically pericardial thickness ([2,3][2]) as well as distorted ventricular

Computationally simulated fractional flow reserve from coronary computed tomography angiography based on fractional myocardial mass

Computed tomography angiography (CCTA)-based calculations of fractional flow reserve (FFR) can improve the diagnostic performance of CCTA for physiologically significant stenosis but the computational resource requirements are high. This study aimed at establishing a simple and efficient algorithm for computing simulated FFR (S-FFR). A total of 107 patients who underwent CCTA and invasive FFR measurements were enrolled in the study. S-FFR was calculated using 145 evaluable coronary arteries with off-the-shelf softwares. FFR ≤ 0.80 was a reference threshold for diagnostic performance of diameter stenosis (DS) ≥ 50%, DS ≥ 70%, or S-FFR ≤ 0.80. FFR ≤ 0.80 was identified in 78 vessels (54%). In per-vessel analysis, S-FFR showed good correlation (r = 0.83) and agreement (mean difference = 0.02 ± 0.08) with FFR. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of S-FFR ≤ 0.80 for FFR ≤ 0.80 were 84%, 92%, 92%, 83%, and 88%, respectively. S-FFR ≤ 0.80 showed much higher predictive performance for FFR ≤ 0.80 compared with DS ≥ 50% or DS ≥ 70% (c-statistics = 0.92 vs. 0.58 or 0.65, p < 0.001, all). The classification agreement between FFR and S-FFR was > 80% when the average of FFR and S-FFR was < 0.76 or > 0.86. Per-patient analysis showed consistent results. In this study, a simple and computationally efficient simulated FFR (S-FFR) algorithm is designed and tested using non-proprietary off-the-shelf software. This algorithm may expand the accessibility of clinical applications for non-invasive coronary physiology study.

TCT-514 Comparison of angiographic scores and fractional myocardial mass: Use of fractional myocardial mass for comprehensive evaluation of coronary artery disease

FMM is a vessel-specific myocardial mass derived from coronary computed tomography angiography (CCTA) and enables quantitative assessment of potentially ischemic myocardial mass. We compared FMM with semi-quantitative angiographic scores which have been developed to evaluate the risk and burden of

DIAGNOSIS OF PHYSIOLOGICALLY SIGNIFICANT CORONARY ARTERY STENOSES BY TRANSLUMINAL ATTENUATION GRADIENT OF 64-DETECTOR ROW CORONARY COMPUTED TOMOGRAPHY ANGIOGRAPHY: A VALIDATION STUDY WITH FRACTIONAL FLOW RESERVE

Results: A total of 45 (44.1%) vessels showed FFR ≤ 0.80. The overall diagnostic performance of TAG determined by ROC analysis was moderate (AUC= 0.660+/-0.057). The sensitivity, specificity, PPV and NPV of TAG cut-off <= -0.654 (HU/mm) for FFR ≤ 0.80 were 44%, 91%, 79%, and 68% on a per-vessel basis. At present, QCA was done in 82 cases. By net reclassification index (NRI) analysis, TAG cutoff= 50% by QCA (NRI=-3.7%, p=0.20). TAG was much worse than QCA especially in LAD group (N=47, NRI=-25.5%, p=0.013), but was comparable in non-LAD group (N=35, NRI=25.7%, p=0.79).

DELAYED HYPER-ENHANCEMENT PATTERN OF CMR IN ISCHEMIC VERSUS NON-ISCHEMIC CARDIOMYOPATHY BASED ON CONVENTIONAL DIAGNOSIS

Delayed hyper-enhancement (DHE) of cardiac magnetic resonance (CMR) has been reported to help identify significant coronary artery disease (CAD). We investigated that DHE pattern of ischemic (ICM) and non-ischemic cardiomyopathy (NICM) with severe myocardial dysfunction based on conventional