Value of fractional flow reserve derived from coronary computed tomographic angiography and plaque quantitative analysis in predicting adverse outcomes of non-obstructive coronary heart disease / 中华危重病急救医学

OBJECTIVE@#To investigate the value of coronary computed tomographic angiography (CCTA)-based fractional flow reserve (CT-FFR) and plaque quantitative analysis in predicting adverse outcomes in patients with non-obstructive coronary heart disease (CAD).@*METHODS@#Clinical data of patients with non-obstructive CAD who underwent CCTA at the Affiliated Hospital of Jiangnan University from March 2014 to March 2018 were retrospectively analyzed and followed up, and the occurrence of major adverse cardiovascular event (MACE) was recorded. The patients were divided into MACE and non-MACE groups according to the occurrence of MACE. The clinical data, CCTA plaque characteristics including plaque length, stenosis degree, minimum lumen area, total plaque volume, non-calcified plaque volume, calcified plaque volume, plaque burden (PB) and remodelling index (RI), and CT-FFR were compared between the two groups. Multivaritate Cox proportional risk model was used to evaluate the relationship between clinical factors, CCTA parameters and MACE. The receiver operator characteristic curve (ROC curve) was used to assess the predictive power of outcome prediction model based on different CCTA parameters.@*RESULTS@#Finally 217 patients were included, of which 43 (19.8%) had MACE and 174 (80.2%) did not. The median follow-up interval was 24 (16, 30) months. The CCTA showed that patients in the MACE group had more severe stenosis than that in the non-MACE group [(44.3±3.8)% vs. (39.5±2.5)%], larger total plaque volume and non-calcified plaque volume [total plaque volume (mm3): 275.1 (197.1, 376.9), non-calcified plaque volume (mm3): 161.5 (114.5, 307.8) vs. 117.9 (77.7, 185.5)], PB and RI were larger [PB: 50.2% (42.1%, 54.8%) vs. 45.1% (38.2%, 51.7%), RI: 1.19 (0.93, 1.29) vs. 1.03 (0.90, 1.22)], CT-FFR value was lower [0.85 (0.80, 0.88) vs. 0.92 (0.87, 0.97)], and the differences were statistically significant (all P < 0.05). Cox regression analysis showed that non-calcified plaques volume [hazard ratio (HR) = 1.005. 95% confidence interval (95%CI) was 1.025-4.866], PB ≥ 50% (HR = 3.146, 95%CI was 1.443-6.906), RI ≥ 1.10 (HR = 2.223, 95%CI was 1.002-1.009) and CT-FFR ≤ 0.87 (HR = 2.615, 95%CI was 1.016-6.732) were independent predictors of MACE (all P < 0.05). The model based on CCTA stenosis degree+CT-FFR+quantitative plaque characteristics (including non-calcified plaque volume, RI, PB) [area under the ROC curve (AUC) = 0.91, 95%CI was 0.87-0.95] had significantly better predictive efficacy for adverse outcomes than the model based on CCTA stenosis degree (AUC = 0.63, 95%CI was 0.54-0.71) and the model based on CCTA stenosis degree+CT-FFR (AUC = 0.71, 95%CI was 0.63-0.79; both P < 0.01).@*CONCLUSIONS@#CT-FFR and plaque quantitative analysis based on CCTA are helpful in predicting adverse outcomes in patients with non-obstructive CAD. Non-calcified plaque volume, RI, PB and CT-FFR are important predictors of MACE. Compared with the prediction model based on stenosis degree and CT-FFR, the combined plaque quantitative index can significantly improve the prediction efficiency of adverse outcomes in patients with non-obstructive CAD.

Research progress on image-based calculation of coronary artery fractional flow reserve / 生物医学工程学杂志

Coronary artery fractional flow reserve (FFR) is a critical physiological indicator for assessment of impaired blood flow caused by coronary artery stenosis. The wire-based invasive measurement of blood flow pressure gradient across stenosis is the gold standard for clinical measurement of FFR. However, it has the risk of vascular injury and requires the use of vasodilators, increasing the time and overall cost of interventional examination. Coronary imaging is playing an important role in clinical diagnosis of stenotic lesions, evaluation of severity of lesions, and planning of therapies. In recent years, the computation of FFR based on the physiological information of blood flow obtained from routinely collected coronary image data has become a research focus in this field. This technique reduces the cost of physiological assessment of coronary lesions and the use of pressure wires. It is beneficial to strengthen the physiological guidance in interventional therapy. In order to better understand this emerging technique, this paper highlights its implementation principle and diagnostic performance, analyzes practical problems and current challenges in clinical applications, and discusses possible future development.

Utilidad de la tomografía de coherencia óptica como guía en el tratamiento del síndrome coronario agudo: reporte de un caso / Utility of optical coherence tomography to guide treatment in acute coronary syndromes: case report / Utilidade da tomografia de coerência óptica como guia no tratamento da síndrome coronariana aguda: relato de um caso

La tomografía de coherencia óptica (OCT) es una técnica de imagen endovascular con elevada resolución espacial que permite evaluar las diferentes estructuras que componen la pared de las arterias coronarias, caracterizar morfológicamente la placa aterosclerótica y establecer el mecanismo fisiopatológico subyacente en los síndromes coronarios agudos (SCA). Se presenta el caso clínico de un paciente con infarto agudo de miocardio, donde la OCT evidenció que la reducción de la luz arterial estaba determinada principalmente por la presencia de trombo, a la vez que demostró una disrupción endotelial (ruptura de placa) como mecanismo fisiopatológico subyacente. Se adoptó una estrategia invasivo-conservadora, donde finalmente no se implantó stent. La información surgida de la OCT en este caso particular fue fundamental en la toma de decisiones.

Optical coherence tomography (OCT) is an endovascular imaging technique with high spatial resolution. It allows to evaluate the different structures that compose coronary arteries' wall, morphologically characterize atherosclerotic plaques and establish the underlying pathophysiological mechanism in acute coronary syndromes (ACS). The case of a patient with acute myocardial infarction is presented, in which OCT showed that the reduction of arterial lumen was determined mainly by the presence of thrombus, while also demonstrated endothelial disruption (plaque rupture) as the underlying pathophysiological mechanism. An invasive-conservative strategy was adopted and finally stent was not implanted. The information that emerged from the OCT in this particular case was fundamental in decision-making.

A tomografia de coerência óptica (OCT) é uma técnica de imagem endovascular com alta resolução espacial que permite a avaliação das diferentes estruturas que compõem a parede das artérias coronárias, a caracterização morfológica da placa aterosclerótica e o estabelecimento do mecanismo fisiopatológico subjacente de síndrome coronariana aguda (SCA). Apresentamos o caso clínico de um paciente com enfarte agudo do miocárdio, onde a OCT mostrou que a redução do lúmen arterial foi determinada principalmente pela presença de trombo, ao mesmo tempo que demonstrou uma ruptura endotelial (ruptura da placa) como causa fisiopatológica subjacente. Adotou-se uma estratégia invasiva-conservadora, onde finalmente o stent não foi implantado. As informações obtidas da OCT neste caso específico foram fundamentais na tomada de decisão.

Diagnostic efficiency and incremental value of myocardial blood flow quantification by CZT SPECT for patients with coronary artery disease / 中华心血管病杂志

Objective: To investigate the diagnostic efficiency and incremental value of quantitative myocardial blood flow measurements by Cadmium-Zine-Telluride (CZT) single photon emission computed tomography (SPECT) dynamic myocardial perfusion imaging (MPI) in patients with coronary artery disease (CAD) compared with traditional semi-quantitative measurements by MPI. Methods: This is a retrospective, cross-sectional study. We retrospectively analyzed clinical data of patients with suspected or known CAD, who underwent the dynamic MPI quantitative blood flow measurement of CZT SPECT in TEDA International Cardiovascular Hospital from October 2018 to December 2020. Clinical data, semi-quantitative parameters (stress score (SS), rest score (RS) and different score (DS)) and myocardial quantitative blood flow parameters (rest myocardial blood flow (rMBF), stress myocardial blood flow (sMBF) and myocardial flow reserve (MFR)) were analyzed. According to the results of coronary angiography, patients were divided into the stenosis group and the control group with coronary artery stenosis ≥50% or ≥75% as the diagnosis criteria. The differences of quantitative and semi-quantitative parameters between the two groups were compared, and the diagnostic efficacy was compared by receiver operating characteristic(ROC) curve. Results: A total of 98 patients with a mean age of (62.1±8.7) years were included in the study, including 66 males (67%). At the patient level, with the positive standard of coronary artery stenosis≥50%, the left ventricle (LV) stress MBF (LV-sMBF) ((1.36±0.45) ml·min-1·g-1) and LV-MFR (1.45±0.43) of the stenosis group were lower than the LV-sMBF ((2.09±0.64) ml·min-1·g-1) and LV-MFR (2.17±0.54) of control group; summed SS and summed DS were higher than control group (all P<0.05). With the positive standard of coronary artery stenosis ≥75%, the LV-sMBF ((1.19±0.34) ml·min-1·g-1) and LV-MFR (1.34±0.35) of stenosis group were lower than the LV-sMBF ((1.94±0.63) ml·min-1·g-1) and MFR (2.00±0.58) of control group; all semi-quantitative parameters were higher than control group (all P<0.05). At the vascular level, with coronary artery stenosis ≥50% as the diagnosis criteria, the sMBF ((1.26±0.49) ml·min-1·g-1) and MFR (1.35±0.46) of stenosis group were lower than the sMBF ((1.95±0.70) ml·min-1·g-1) and MFR (2.05±0.65) of control group; SS and DS were higher than control group (all P<0.05). With coronary artery stenosis≥75% as the diagnosis criteria, the sMBF ((1.12±0.41) ml·min-1·g-1) and MFR (1.25±0.38) of stenosis group were lower than the sMBF ((1.84±0.70) ml·min-1·g-1) and MFR (1.93±0.66) of control group; all semi-quantitative parameters were higher than control group (all P<0.05). With coronary artery stenosis≥50% as the diagnosis criteria and CAG as the reference standard, the AUC and 95%CI of myocardial quantitative blood flow parameters indicated by ROC curve for diagnosis of CAD were 0.830 (0.783-0.877). The sensitivity (86.1% vs. 61.5%), specificity (82.6% vs. 73.8%), positive predictive value (77.8% vs. 62.5%), negative predictive value (89.3% vs. 73.0%) and accuracy (84.0% vs. 68.7%) were all higher than the semi-quantitative parameters (all P<0.05). With coronary artery stenosis≥75% as the diagnosis criteria, the AUC and 95%CI of myocardial quantitative blood flow parameters indicated by ROC curve for diagnosis of CAD were 0.832(0.785-0.879). The sensitivity (89.2% vs. 67.6%), negative predictive value (95.5% vs. 86.2%) and accuracy (80.6% vs. 68.0%) were all higher than semi-quantitative parameters (all P<0.05). Conclusion: Compared with traditional SPECT MPI derived semi-quantitative parameters, diagnostic efficacy for CAD is higher using CZT SPECT quantitative myocardial blood flow parameters, this strategy thus has additional diagnostic benefits and incremental value on the diagnosis of CAD.

Clinical Value of 1.5-T Non-contrast Whole-heart Magnetic Resonance Coronary Angiography in Evaluating the Severity of Coronary Stenosis / 中国医学科学院学报

Objective To evaluate the diagnostic performance of 1.5-T non-contrast free-breathing whole-heart magnetic resonance coronary angiography(MRCA)for≥50% and≥70% coronary artery stenosis in coronary artery disease(CAD).Methods Forty-one patients clinically scheduled for invasive coronary angiography(ICA)underwent 1.5-T non-contrast free-breathing whole-heart MRCA.The diagnostic performance for≥50% and≥70% stenosis was evaluated and compared using ICA as a reference standard.Results MRCA was completed in all the 41 patients with the total acquisition time of(10.1 ± 2.2)min.The sensitivity,specificity,and accuracy of MRCA for≥50% and≥70% stenosis were 100%(95%

Type 2 myocardial infarction resulted from the left thoracic stomach

Abstract The universal definition of myocardial infarction (MI) provides five subtypes of acute myocardial infarction (AMI). We present an interesting case of a type 2 myocardial infarction caused by the dilation of the left thoracic stomach.

Diagnostic performance of qfr for the evaluation of intermediate coronary artery stenosis confirmed by fractional flow reserve

Abstract Introduction: Quantitative flow ratio (QFR) is a novel method enabling efficient computation of FFR from three-dimensional quantitative coronary angiography (3D QCA) and thrombolysis in myocardial infarction (TIMI) frame counting. We decided to perform a systematic review and quantitative meta-analysis of the literature to determine the correlation between the diagnosis of functionally significant stenosis obtained by QFR versus FFR and to determine the diagnostic accuracy of QFR for intermediate coronary artery stenosis. Methods: We searched PubMed, Embase, and Web of Science for studies concerning the diagnostic performance of QFR. Our meta-analysis was performed using the DerSimonian and Laird random effects model to determine sensitivity, specificity, positive likelihood ratio (LR+), negative likelihood ratio (LR-), and diagnostic odds ratio (DOR). The sROC was used to determine diagnostic test accuracy. Results: Nine studies consisting of 1175 vessels in 1047 patients were included in our study. The pooled sensitivity, specificity, LR+, LR-, and DOR for QFR were 0.89 (95% CI: 0.86-0.92), 0.88 (95% CI: 0.86-0.91), 6.86 (95% CI,: 5.22-9.02), 0.14 (95% CI: 0.10-0.21), and 53.05 (95% CI: 29.75-94.58), respectively. The area under the summary receiver operating characteristic (sROC) curve for QFR was 0.94. Conclusion: QFR is a simple, useful, and noninvasive modality for diagnosis of functional significance of intermediate coronary artery stenosis.

Does moderate coronary stenosis affect the fate of the left internal thoracic artery graft?

Abstract Introduction: In this study we try to observe the fate of the left internal thoracic artery grafts that were bypassed to left anterior descending artery with moderate stenosis identified with fractional flow reserve (FFR) technique. Doppler ultrasonography was chosen as a noninvasive screening method. Methods: A total of 30 patients who underwent coronary artery bypass grafting depending on results of the fractional flow reserve between January 2007 and January 2012, were subjected to transthoracic color Doppler ultrasonographic evaluation irrespective of the presence of symptoms, and the presence of a systolic-diastolic flow pattern was investigated using the supraclavicular approach. Results: The left internal thoracic artery graft was found to be functional in 63.3% of patients within a mean period of 35.1±19.7 months between coronary bypass and color Doppler ultrasonography. This period was found to be 29.4±19.6 months in the functional graft group, and 44.7±16.6 months in the dysfunctional graft group (P=0.046). Preoperative complaints of angina were reported to fall from 88.9% to 16.7% in the functional graft group, when compared to the postoperative period (P<0.001), but fell from 90.9% to 36.4% in the dysfunctional graft group (P=0.034). Conclusion: Functional left internal thoracic artery graft rates of the study population were found to be lower than the studies reported in the literature.

Association of serum thyrotropin levels with coronary artery disease documented by quantitative coronary angiography: a transversal study

ABSTRACT Objective: The association between coronary artery disease (CAD) and thyroid function remains controversial. We evaluated the thyroid function and graduated well-defined CAD as confirmed by quantitative coronary angiography (CA). Subjects and methods: We evaluated the serum TSH, free thyroxine, free triiodothyronine and thyroid antibody levels in 300 consecutive patients (age 61.6 ± 9.9 years and 54% were male) undergoing CAD diagnosis as confirmed by CA. Plaques with ≥ 50% stenosis being indicative of obstructive CAD, and patients were divided into groups according to main epicardial coronary arteries with plaques (0, 1, 2, 3). Lipid profiles and a homeostasis model assessment (HOMA-IR) were determined. Results: Serum median (25% and 75% percentile) TSH levels in patients with group 2 and 3 (2.25; 1.66-3.12 mU/L and 4.99; 4.38-23.60 mU/L, respectively) had significantly higher TSH concentrations (p < 0.0001) than the group 0 (1.82; 1.35-2.51 mU/L). Furthermore, patients of group 3 had higher TSH concentration (p < 0.0001) than those of group 1 (1.60; 0.89-2.68 mU/L). Group 3 were older (64 ± 8.5 vs. 59 ± 9.5, p = 0.001), had more patients with dyslipidemia (84% versus 58%, p < 0.001), male (54% versus 44%, p = 0.01), hypertension (100% versus 86%, p < 0.001), and smoking (61% versus 33%, p < 0.001) than group 0. Multivariate stepwise logistic analysis showed TSH, age, HbA1c, and HOMA-IR were the CAD associated variables. Conclusions: In this cohort, elevated TSH levels in the high normal range or above are associated with the presence and severity of CAD besides may represent a weak CAD risk factor.

Off-pump coronary artery bypass grafting in moyamoya disease: a case report

Abstract Moyamoya disease is a rare, idiopathic, progressive, occlusive disease of the internal carotid artery characterized by the development of collateral vasculature in the brain base. In patients with accompanying coronary artery disease, cardiopulmonary bypass posses a potential risk for perioperative cerebral ischemic complication. Herein, we report a 53-year-old male case of Moyamoya disease and coronary artery disease who was treated with off-pump coronary artery bypass grafting.

Factors Associated With Coronary Artery Disease Progression Assessed By Serial Coronary Computed Tomography Angiography / Fatores Associados com Progressão da Doença Arterial Coronariana Avaliada por Angiografia Coronariana por Tomografia Computadorizada Seriada

Abstract Background: Coronary computed tomography angiography (CCTA) allows for noninvasive coronary artery disease (CAD) phenotyping. Factors related to CAD progression are epidemiologically valuable. Objective: To identify factors associated with CAD progression in patients undergoing sequential CCTA testing. Methods: We retrospectively analyzed 384 consecutive patients who had at least two CCTA studies between December 2005 and March 2013. Due to limitations in the quantification of CAD progression, we excluded patients who had undergone surgical revascularization previously or percutaneous coronary intervention (PCI) between studies. CAD progression was defined as any increase in the adapted segment stenosis score (calculated using the number of diseased segments and stenosis severity) in all coronary segments without stent (in-stent restenosis was excluded from the analysis). Stepwise logistic regression was used to assess variables associated with CAD progression. Results: From a final population of 234 patients, a total of 117 (50%) had CAD progression. In a model accounting for major CAD risk factors and other baseline characteristics, only age (odds ratio [OR] 1.04, 95% confidence interval [95%CI] 1.01-1.07), interstudy interval (OR 1.03, 95%CI 1.01-1.04), and past PCI (OR 3.66, 95%CI 1.77-7.55) showed an independent relationship with CAD progression. Conclusions: A history of PCI with stent placement was independently associated with a 3.7-fold increase in the odds of CAD progression, excluding in-stent restenosis. Age and interstudy interval were also independent predictors of progression.

Resumo Fundamento: Angiografia coronariana por tomografia computadorizada (ACTC) permite fenotipagem não invasiva da doença arterial coronariana (DAC). Fatores relacionados à progressão da DAC têm valor epidemiológico. Objetivo: Identificar os fatores associados com a progressão da DAC em pacientes submetidos à avaliação sequencial por ACTC. Métodos: Nós analisamos retrospectivamente 384 pacientes consecutivos que apresentavam pelo menos duas avaliações por ACTC entre dezembro de 2005 e março de 2013. Devido às limitações na quantificação da progressão da DAC, os pacientes que haviam sido submetidos previamente à revascularização cirúrgica ou intervenção coronariana percutânea (ICP) entre as avaliações foram excluídos. A progressão da DAC foi definida como qualquer aumento no escore adaptado de estenose segmentar (calculado com utilização do número de segmentos afetados e gravidade da estenose) em todos os segmentos coronarianos sem stent (restenose intra-stent foi excluída da análise). Regressão logística stepwise foi utilizada para avaliar as variáveis associadas com a progressão da DAC. Resultados: De uma população final de 234 pacientes, um total de 117 (50%) pacientes apresentaram progressão da DAC. Em um modelo considerando os principais fatores de risco para DAC e outras características basais, apenas a idade (odds ratio [OR] 1,04, intervalo de confiança de 95% [IC95%] 1,01-1,07), intervalo entre avaliações (OR 1,03, IC95% 1,01-1,04) e ICP prévia (OR 3,66, IC95% 1,77-7,55) mostraram uma relação independente com a progressão da DAC. Conclusões: Uma história de ICP com implante de stent esteve independentemente associada a um aumento de 3,7 vezes na chance de progressão da DAC, excluindo a restenose intra-stent. Idade e intervalo entre avaliações também foram preditores independentes de progressão.

Comparative Study between Perfusion Changes and Positive Findings on Coronary Flow Reserve / Estudo Comparativo entre Alterações de Perfusão e Achados Positivos da Reserva de Fluxo Coronariano

Abstract Background: Functional assessment of coronary artery obstruction is used in cardiology practice to correlate anatomic obstructions with flow decrease. Among such assessments, the study of the coronary fractional flow reserve (FFR) has become the most widely used. Objective: To evaluate the correlation between FFR and findings of ischemia obtained by noninvasive methods including stress echocardiography and nuclear medicine and the presence of critical coronary artery obstruction. Methods: Retrospective study of cases treated with systematized and standardized procedures for coronary disease between March 2011 and August 2014. We included 96 patients with 107 critical coronary obstructions (> 50% in the coronary trunk and/or ≥ 70% in other segments) estimated by quantitative coronary angiography (QCA) and intracoronary ultrasound (ICUS). All cases presented ischemia in one of the noninvasive studies. Results: All 96 patients presented ischemia (100%) in one of the functional tests. On FFR study with adenosine 140 g/kg/min, 52% of the cases had values ≤ 0.80. On correlation analysis for FFR ≤ 0.80, the evaluation of sensitivity, specificity, positive and negative predictive values, accuracy, and ROC curve in relation to the stenosis degree and length, and presence of ischemia, no significant values or strong correlation were observed. Conclusion: Coronary FFR using a cut-off value of 0.80 showed no correlation with noninvasive ischemia tests in patients with severe coronary artery obstructions on QCA and ICUS.

Resumo Fundamento: A avaliação funcional da obstrução arterial coronariana é empregada na prática cardiológica para correlacionar a obstrução anatômica e a queda de fluxo. Dentre as formas de avaliação, o estudo da reserva fracionada de fluxo (RFF) coronariano se tornou a mais utilizada. Objetivo: Avaliar a correlação entre a RFF com achados de isquemia, obtidos por métodos não invasivos como a ecocardiografia de estresse ou medicina nuclear, e a presença de obstrução crítica da artéria coronária. Métodos: Estudo retrospectivo de casos tratados com procedimentos sistematizados e padronizados para doença coronariana entre março de 2011 e agosto de 2014. Foram incluídos 96 pacientes com 107 obstruções coronarianas críticas (> 50% no tronco da coronária e/ou ≥ 70% nos demais segmentos) estimadas por angiografia coronariana quantitativa (ACQ) e ultrassonografia intracoronariana (USIC). Todos os casos apresentaram isquemia em um dos estudos não invasivos. Resultados: Ao estudo da RFF com adenosina na dose de 140 µg/kg/min, valores ≤ 0,80 foram encontrados em 52% dos casos. Na análise de correlação para RFF ≤ 0,80, avaliando-se sensibilidade/especificidade, valor preditivo positivo/negativo, acurácia e curva ROC em relação ao grau de estenose, extensão da estenose e presença de isquemia, não foram observados valores de significância ou de forte correlação. Conclusão: A RFF coronariana a um valor de corte de 0,80 não apresentou correlação com testes não invasivos de isquemia em pacientes com obstruções coronarianas graves à ACQ e USIC.

Coronary Angiography in Isolated Hearts and Its Forensic Application / 法医学杂志

OBJECTIVES@#To check the isolated heart by coronary angiography to discover the location, nature and degree of the coronary artery lesions more accurately and increase the comprehensive evaluation ability of cardiovascular disease.@*METHODS@#Ten fresh isolated hearts with different causes of death were extracted and injected with barium sulphate as contrast substance by ring injector, then developed under Xper FD20 angiography equipment. The obtained pictures and image data were handled by three-dimensional angiography images with the software attached to the angiography equipment. The coronary artery tissues were HE stained and observed by microscope. The HE staining results were compared with the angiographic results.@*RESULTS@#The imaging data obtained from the 10 cases for examination showed 8 cases without coronary artery stenosis and 2 cases with Ⅲ, Ⅳ coronary artery stenosis, which were consistent with HE staining results of coronary artery organization and the both results were confirmed.@*CONCLUSIONS@#Isolated coronary angiography has an unique advantage for accurate grading of classification of coronary artery stenosis, examination of vascular malformation and tiny lesions, which can provide reference for the localization of small lesions and basis during the autopsy for identification conclusion.

Grado de estenosis y vulnerabilidad de las lesiones coronarias / Degree of stenosis and vulnerability of coronary artery lesions

La angiografía coronaria ha sido y continúa siendo el pilar sobre el cual se deciden las intervenciones terapéuticas en la enfermedad coronaria constituyendo el grado de estenosis de las placas ateromatosas uno de los principales marcadores de isquemia miocárdica y por lo tanto del pronóstico de la enfermedad. Sin embargo, es un hecho repetidamente documentado que los fenómenos coronarios agudos se producen con mayor frecuencia en placas con estenosis angiográficamente no significativas; por lo tanto, la vulnerabilidad de las placas no parece tener relación con su grado de estenosis y en consecuencia tampoco con la producción de isquemia miocárdica. Esta conclusión no concuerda con los hallazgos histopatológicos ni con los grados de severidad de las estenosis que comprometen el flujo coronario. El objetivo de la presente comunicación es tratar de aclarar esta controversia analizando la información entregada por la histopatología de las lesiones agudas culpables de los infartos. Precisar si las lesiones coronarias crónicas que producen isquemia (probables causantes de futuros infartos) se correlacionan con el grado de estenosis anatómica; proponer el posible mecanismo que vincula el grado de estenosis a la vulnerabilidad de las placas y esbozar una explicación para conciliar los hallazgos angiográficos con los his-topatológicos y funcionales.

Coronary angiography has long been and is still the basic method for deciding coronary interventions, and the severity of stenosis remains the main prognostic marker of the disease. However, plaque vulnerability does not appear to be associated with a greater degree of angiographic stenosis, which is not consistent with histopathological findings or with physiological assessment of ischemia-producing lesions. The purpose of this article is to briefly review this controversy while suggesting that plaques vulnerability correlate with the degree of anatomical and functional stenosis, and to describe the potential mechanism that could determine this vulnerability as well as to give likely explanations that reconcile angiographic findings with histopathological and functional observations.

Coronary Computed Tomographic Angiography Does Not Accurately Predict the Need of Coronary Revascularization in Patients with Stable Angina

PURPOSE: To evaluate the ability of coronary computed tomographic angiography (CCTA) to predict the need of coronary revascularization in symptomatic patients with stable angina who were referred to a cardiac catheterization laboratory for coronary revascularization. MATERIALS AND METHODS: Pre-angiography CCTA findings were analyzed in 1846 consecutive symptomatic patients with stable angina, who were referred to a cardiac catheterization laboratory at six hospitals and were potential candidates for coronary revascularization between July 2011 and December 2013. The number of patients requiring revascularization was determined based on the severity of coronary stenosis as assessed by CCTA. This was compared to the actual number of revascularization procedures performed in the cardiac catheterization laboratory. RESULTS: Based on CCTA findings, coronary revascularization was indicated in 877 (48%) and not indicated in 969 (52%) patients. Of the 877 patients indicated for revascularization by CCTA, only 600 (68%) underwent the procedure, whereas 285 (29%) of the 969 patients not indicated for revascularization, as assessed by CCTA, underwent the procedure. When the coronary arteries were divided into 15 segments using the American Heart Association coronary tree model, the sensitivity, specificity, positive predictive value, and negative predictive value of CCTA for therapeutic decision making on a per-segment analysis were 42%, 96%, 40%, and 96%, respectively. CONCLUSION: CCTA-based assessment of coronary stenosis severity does not sufficiently differentiate between coronary segments requiring revascularization versus those not requiring revascularization. Conventional coronary angiography should be considered to determine the need of revascularization in symptomatic patients with stable angina.

Association of Apolipoprotein B/Apolipoprotein A1 Ratio and Coronary Artery Stenosis and Plaques Detected by Multi-Detector Computed Tomography in Healthy Population

Despite the noninvasiveness and accuracy of multidetector computed tomography (MDCT), its use as a routine screening tool for occult coronary atherosclerosis is unclear. We investigated whether the ratio of apolipoprotein B (apoB) to apolipoprotein A1 (apoA1), an indicator of the balance between atherogenic and atheroprotective cholesterol transport could predict occult coronary atherosclerosis detected by MDCT. We collected the data of 1,401 subjects (877 men and 524 women) who participated in a routine health screening examination of Asan Medical Center. Significant coronary artery stenosis defined as > 50% stenosis was detected in 114 subjects (8.1%). An increase in apoB/A1 quartiles was associated with increased percentages of subjects with significant coronary stenosis and noncalcified plaques (NCAP). After adjustment for confounding variables, each 0.1 increase in serum apoB/A1 was significantly associated with increased odds ratios (ORs) for coronary stenosis and NCAP of 1.23 and 1.18, respectively. The optimal apoB/A1 ratio cut off value for MDCT detection of significant coronary stenosis was 0.58, which had a sensitivity of 70.2% and a specificity of 48.2% (area under the curve, 0.61; 95% CI, 0.58-0.63, P < 0.001). Our results indicate that apoB/A1 ratio is a good indicator of occult coronary atherosclerosis detected by coronary MDCT.