El puntaje de Framingham ayudaría en la estratificación del riesgo de pacientes con ergometría positiva y SPECT normal / The Framingham score could help in risk stratification of patients with positive ergometry and normal SPECT

Antecedentes. El valor pronóstico de una ergometría positiva en el contexto de imágenes tomográficas de perfusión miocárdica de estrés y reposo (SPECT) normales no está bien establecido. Objetivos. Documentar la incidencia de infarto, muerte y revascularización coronaria en pacientes con una ergometría positiva de riesgo intermedio e imágenes de perfusión SPECT normales, y explorar el potencial valor del puntaje de riesgo de Framingham en la estratificación pronóstica de estos pacientes. Métodos. Cohorte retrospectiva integrada por pacientes que habían presentado síntomas o hallazgos electrocardiográficos compatibles con enfermedad arterial coronaria durante la prueba de esfuerzo, con criterios de riesgo intermedio en la puntuación de Duke y perfusión miocárdica SPECT normal. Fueron identificados a partir de la base de datos del laboratorio de cardiología nuclear del Instituto de Cardiología y Cirugía Cardiovascular de la ciudad de Posadas, Argentina. Resultados. Fueron elegibles 217 pacientes. El seguimiento fue de 3 1,5 años. La sobrevida libre de eventos (muerte,infarto de miocardio no fatal, angioplastia coronaria o cirugía de bypass de arteria coronaria) a uno, tres y cinco años fue significativamente menor (Log-rank test, p= 0,001) en el grupo con puntaje de Framingham alto o muy alto (77, 71y 59 %, respectivamente) que en el grupo de puntaje bajo o intermedio (89, 87 y 83 %). Tomando como referencia a los pacientes con riesgo bajo en el puntaje de Framingham, luego de ajustar por edad, sexo y puntaje de Duke, los pacientes categorizados en los estratos alto y muy alto riesgo del puntaje de Framingham presentaron una incidencia del evento combinado cercana al triple (hazard ratio [HR] 2,81; intervalo de confianza [IC] del 95 % 0,91 a 8,72; p= 0,07 y HR 3,61;IC 95 % 1,23 a 10,56; p= 0,019 respectivamente). Conclusiones. La estimación de riesgo con el puntaje de Framingham sería de ayuda en la estratificación pronóstica de los pacientes con ergometría positiva y SPECT normal. (AU)

Background. The prognostic value of positive exercise testing with normal SPECT myocardial perfusion imaging is not well established. Objectives. To document the incidence of infarction, death, and coronary revascularization in patients with a positive intermediate-risk exercise test and normal SPECT perfusion images and to explore the potential value of the Framingham Risk Score in the prognostic stratification of these patients. Methods. A retrospective cohort comprised patients who presented symptoms or electrocardiographic findings compatible with coronary artery disease during the stress test, with intermediate risk criteria in the Duke score and normal SPECT myocardial perfusion. They were identified from the database of the nuclear cardiology laboratory of the Instituto de Cardiología y Cirugía Cardiovascular of Posadas, Argentina. Results. 217 patients were eligible. Follow-up was 3 1.5 years. Event-free survival (death, non-fatal myocardial infarction, coronary angioplasty, or coronary artery bypass surgery) at one, three, and five years was significantly lower (Log-ranktest, p: 0.001) in the group with a score of Framingham high or very high (77, 71 and 59 %, respectively) than in the lowor intermediate score group (89, 87 and 83 %). Taking as reference the low-risk patients in the Framingham score, after adjusting for age, sex, and Duke score, the patients categorized in the high-risk and very high-risk strata showed about three times higher incidence of the combined event (hazard ratio [HR] 2.81; 95 % confidence interval [CI] 0.91 to 8.72;p=0.07 and HR 3.61; 95 % CI 1.23 to 10.56; p=0.019 respectively). Conclusions. Risk estimation with the Framingham score would be helpful in the prognostic stratification of patients with positive exercise testing and normal SPECT. (AU)

El dilema clínico frente a los pacientes con ergometría positiva y prueba de perfusión miocárdica con SPECT normal / The clinical dilemma facing patients with positive stress test and normal SPECT myocardial perfusion imaging

La evaluación de la perfusión miocárdica con SPECT combina una prueba de esfuerzo (ergometría o estrés farmacológico) junto a imágenes de perfusión con radioisótopos. Este estudio es útil para establecer el diagnóstico de enfermedad arterial coronaria, estratificar el riesgo de infarto y tomar decisiones terapéuticas. Un resultado normal aporta un alto valor predictivo negativo, es decir, una muy baja probabilidad de que el paciente presente eventos cardiovasculares. El hallazgo de signos de isquemia en la ergometría podría poner en jaque el valor predictivo negativo de una perfusión normal. En presencia de este resultado, el paso siguiente es evaluar los predictores de riesgo en la ergometría, el riesgo propio del paciente en función de los antecedentes clínicos y el puntaje cálcico coronario, cuando este se encuentra disponible. Ante la presencia concomitante de otros marcadores de riesgo se sugiere completar la evaluación con un estudio anatómico.El uso de nuevas tecnologías podría mejorar la precisión en la predicción de eventos. (AU)

Assessment of myocardial perfusion with SPECT combines a stress test (ergometry or pharmacological stress) with radioisotope perfusion imaging. This test is helpful to diagnose coronary artery disease, stratify the risk of heart attack, and make therapeutic decisions. A normal result provides a high negative predictive value; therefore, the probability of cardiovascular events is very low. Signs of ischemia on an ergometry could jeopardize the negative predictive value of normal perfusion. In this clinical setting, the next step is to evaluate the risk predictors in the stress test, the individual risk based on the clinical history, and the coronary calcium score when available. Given the simultaneous presence of other risk markers,completing the evaluation with an anatomical study is suggested. The use of new technologies could improve the accuracy of event prediction. (AU)

Impact of statin use on major adverse cardiovascular events in patients with normal stress myocardial perfusion imaging and elevated coronary artery calcium score

INTRODUCTION@#Normal stress myocardial perfusion imaging (MPI) carries a favourable prognosis. Conversely, elevated coronary artery calcium (CAC) is associated with increased major adverse cardiovascular events (MACE). There is limited information on the prognosis and management of patients with elevated CAC and normal MPI. We aimed to assess the outcomes of patients with elevated CAC and normal MPI in relation to post-MPI statin use.@*METHODS@#A retrospective review of normal MPI with CAC score >300 was performed between 1 March 2016 and 31 January 2017 in a Singapore tertiary hospital. Patients with known atherosclerotic cardiovascular disease or left ventricular ejection fraction <50% on MPI were excluded. Patient demographics, prescriptions and MACE (cardiac death, nonfatal myocardial infarction and/or ischaemic stroke) at 24 months after MPI were traced using electronic records. Binary logistic regression was used to evaluate for independent predictors of MACE.@*RESULTS@#We included 311 patients (median age 71 years, 56.3% male), of whom 65.0% were on moderate to high-intensity statins (MHIS) after MPI. MACE was significantly lower in the post-MPI MHIS group (3.5% vs. 9.2%, P = 0.035). On univariate binary logistic regression, post-MPI MHIS use was the only significant predictor for MACE (odds ratio [OR] 0.355 [95% confidence interval (CI) 0.131-0.962], P = 0.042), even after multivariate adjustment (adjusted OR 0.363, 95% confidence interval 0.134-0.984, P = 0.046).@*CONCLUSION@#Post-MPI MHIS use is associated with lower MACE and is an independent negative predictor for 24-month MACE among patients with normal MPI and CAC >300.

Relação entre a Relação Fibrinogênio/Albumina e a Perfusão Microvascular em Pacientes Submetidos à Intervenção Coronária Percutânea Primária para Infarto do Miocárdio com Elevação do Segmento ST: Um Estudo Prospectivo / Relationship between the Fibrinogen/Albumin Ratio and Microvascular Perfusion in Patients Undergoing Primary Percutaneous Coronary Intervention for ST-Elevated Myocardial Infarction: A Prospective Study

Resumo Fundamento A contagem corrigida de quadros TIMI (CTFC), o grau de blush miocárdico (MBG) e a resolução do segmento ST (STR) são parâmetros utilizados para avaliar a reperfusão em nível microvascular em pacientes submetidos à intervenção coronária percutânea primária (ICPp). A relação fibrinogênio/albumina (FAR) tem sido associada a eventos trombóticos em pacientes com infarto do miocárdio com elevação do segmento ST (IAMCSST) e insuficiência venosa crônica. Objetivos Investigar a relação do FAR com CTFC, MBG e STR.Métodos: O estudo incluiu 167 pacientes consecutivos que foram submetidos a ICPp com sucesso para IAMCSST e alcançaram fluxo TIMI-3. Os casos foram divididos em dois grupos, FAR alto (> 0,0765) e FAR baixo (≤ 0,0765), de acordo com o valor de corte desse parâmetro na análise característica do operador do receptor (ROC). STR, CTFC e MBG foram utilizados para avaliar a reperfusão miocárdica. Valores de p<0,05 foram considerados estatisticamente significativos. Resultados O valor CTFC, escore SYNTAX, relação neutrófilos/linfócitos, lipoproteína de baixa densidade, glicose e pico de cTnT foram significativamente maiores, enquanto STR, MBG e FEVE foram menores no grupo FAR alto. A análise de correlação de Spearman revelou relação significativa entre FAR e STR (r=-0,666, p<0,001), MBG (-0,523, p<0,001) e CTFC (r=0,731, p≤0,001). De acordo com a análise de regressão logística, FAR, glicose, pico de cTnT e dor até o tempo de Balão foram os preditores independentes mais importantes de MBG 0/1, CTFC>28 e STR<50%). A análise ROC revelou que o ponto de corte o valor de FAR≥0,0765 foi preditor de STR incompleto com sensibilidade de 71,9% e especificidade de 69,8%, MBG0/1 com sensibilidade de 72,6% e especificidade de 68,6%, e CTFC>28 com sensibilidade de 76% e uma especificidade de 65,8%. Conclusões A FAR é um importante preditor independente de perfusão microvascular em pacientes submetidos a ICPp por IAMCSST.

Abstract Background Correct TIMI frame count (CTFC), myocardial blush grade (MBG), and ST-segment resolution (STR) are parameters used to evaluate reperfusion at the microvascular level in patients that have undergone primary percutaneous coronary intervention (pPCI). Fibrinogen-to-albumin ratio (FAR) has been associated with thrombotic events in patients with ST-elevation myocardial infarction (STEMI) and chronic venous insufficiency. Objectives To investigate the relationship of FAR with CTFC, MBG, and STR. Methods: The study included 167 consecutive patients who underwent successful pPCI for STEMI and achieved TIMI-3 flow. The cases were divided into two groups, high (>0.0765) and low FAR (≤0.0765), according to the cut-off value of this parameter in the receiver operator characteristic analysis (ROC). STR, CTFC, and MBG were used to evaluate myocardial reperfusion. P values<0.05 were considered statistically significant. Results CTFC value, SYNTAX score, neutrophil/lymphocyte ratio, low-density lipoprotein, glucose, and peak cTnT were significantly higher, whereas STR, MBG, and LVEF were lower in the high FAR group. Spearman's correlation analysis revealed a significant relationship between the FAR and STR (r=-0.666, p<0.001), MBG (-0.523, p<0.001), and CTFC (r=0.731, p≤0.001). According to the logistic regression analysis, FAR, glucose, peak cTnT, and pain to balloon time were the most important independent predictors of MBG 0/1, CTFC>28, and STR<50%).ROC analysis revealed that the cut-off value of FAR≥0.0765 was a predictor of incomplete STR with a sensitivity of 71.9 % and a specificity of 69.8 %, MBG0/1 with a sensitivity of 72.6 % and a specificity of 68.6 %, and CTFC >28 with a sensitivity of 76 % and a specificity of 65.8 %. Conclusions FAR is an important independent predictor of microvascular perfusion in patients undergoing pPCI for STEMI.

Associação de Nível de Renda e Doença Isquêmica do Coração: Papel Potencial da Caminhabilidade / Association of Income Level and Ischemic Heart Disease: Potential Role of Walkability

Resumo Fundamento O nível socioeconômico tem sido associado à doença isquêmica do coração (DIC). Bairros de alta renda podem expor os indivíduos a um ambiente construído que promova caminhadas para atividades diárias (caminhabilidade). Faltam dados sobre a associação entre renda e DIC em países de renda média. Também é incerto se a caminhabilidade medeia essa associação. Objetivos Investigar se a renda está associada à DIC em um país de renda média e se a caminhabilidade dos bairros medeia a associação entre renda e DIC. Métodos O presente estudo transversal avaliou 44.589 pacientes encaminhados para imagem de perfusão miocárdica (SPECT-MPI). A renda e a caminhabilidade foram derivadas do setor censitário residencial dos participantes. A pontuação quantitativa da caminhabilidade combinou as seguintes 4 variáveis: conectividade viária, densidade residencial, densidade comercial e uso misto do solo. A DIC foi definida pela presença de perfusão miocárdica anormal durante um estudo SPECT-MPI. Utilizamos modelos ajustados com efeitos mistos para avaliar a associação entre nível de renda e DIC e realizamos uma análise de mediação para medir o percentual da associação entre renda e DIC mediada pela caminhabilidade. Consideramos valores de p abaixo de 0,01 como estatisticamente significativos. Resultados Dos 26.415 participantes, aqueles que residiam no setor censitário do tercil de menor renda eram mais fisicamente inativos (79,1% versus 75,8% versus 72,7%) quando comparados aos setores censitários do tercil de maior renda (p < 0,001). A renda foi associada à DIC (odds ratio: 0,91 [intervalo de confiança de 95%: 0,87 a 0,96] para cada aumento de 1000,00 dólares internacionais na renda), para homens e mulheres igualmente (p para interação = 0,47). Os setores censitários com maior renda estiveram associados a uma melhor caminhabilidade (p < 0,001); no entanto, a caminhabilidade não mediou a associação entre renda e DIC (porcentagem mediada = −0,3%). Conclusões A renda foi independentemente associada a maior prevalência de DIC em um país de renda média, independentemente de gênero. Embora a caminhabilidade tenha sido associada à renda do setor censitário, ela não mediou a associação entre renda e DIC.

Abstract Background Socioeconomic status has been linked to ischemic heart disease (IHD). High-income neighborhoods may expose individuals to a walking-promoting built environment for daily activities (walkability). Data from the association between income and IHD is lacking in middle-income countries. It is also uncertain whether walkability mediates this association. Objectives To investigate whether income is associated with IHD in a middle-income country and whether neighborhood walkability mediates the income-IHD association. Methods This cross-sectional study evaluated 44,589 patients referred for myocardial perfusion imaging (SPECT-MPI). Income and walkability were derived from participants' residential census tract. Walkability quantitative score combined 4 variables: street connectivity, residential density, commercial density, and mixed land use. IHD was defined by abnormal myocardial perfusion during a SPECT-MPI study. We used adjusted mixed effects models to evaluate the association between income level and IHD, and we performed a mediation analysis to measure the percentage of the income-IHD association mediated by walkability. We considered p values below 0.01 as statistically significant. Results From 26,415 participants, those living in the lowest-income tertile census tract were more physically inactive (79.1% versus 75.8% versus 72.7%) when compared to higher-income tertile census tracts (p < 0.001). Income was associated with IHD (odds ratio: 0.91 [95% confidence interval: 0.87 to 0.96] for each 1,000.00 international dollars increase in income) for both men and women equally (p for interaction = 0.47). Census tracts with a higher income were associated with better walkability (p < 0.001); however, walkability did not mediate the income-IHD association (percent mediated = −0.3%). Conclusions Income was independently associated with higher prevalence of IHD in a middle-income country irrespective of gender. Although walkability was associated with census tract income, it did not mediate the income-IHD association.

Assessment of myocardial viability in ischemic heart disease by integrated PET/MR / 中华核医学与分子影像杂志

Objective:To evaluate the value of integrated PET/MR in assessing myocardial viability in ischemic heart disease.Methods:A total of 39 patients (28 males, 11 females; age (60.1±12.0) years) diagnosed with ischemic heart disease in Xuanwu Hospital, Capital Medical University were retrospectively enrolled from September 2020 to December 2021. All patients underwent cardiac 13N-NH 3·H 2O and 18F-FDG PET/MR examinations. Late gadolinium enhancement (LGE) sequence was included in MRI scan. PET and MRI images were analyzed and myocardial viability of each myocardial segment was evaluated according to the American Heart Association (AHA) 17 segment method. The extent of left ventricular infarcted myocardium was measured based on PET and MRI images. Weighted Kappa test was used to evaluate the agreement of PET and MRI in assessing myocardial viability. The extent of infarcted myocardium measured by PET and MRI was compared by paired- t test, and Pearson correlation analysis was used to assess the correlation between them. Results:There was a moderate agreement between PET and MRI in assessing myocardial viability ( Kappa=0.532, P<0.001), with the agreement rate of 69.83%(463/663). There was no significant difference but strong correlation between the extents of infarcted myocardium measured by PET and MRI ((23.89±14.23)% vs (23.55±11.90)%; t=-0.24, P=0.809; r=0.79, P<0.001). In segments with normal perfusion and metabolism on PET, 22.52% (100/444) showed abnormal enhancement on MRI. On the other hand, 39.89% (73/183) of the segments classified as non-viable on MRI showed normal or viable on PET. Conclusion:Integrated PET/MR is able to take full advantage of the complementary nature of PET and MRI, achieving the comprehensive and accurate evaluation of myocardial viability.

Quantitative assessment of right ventricular myocardial blood flow with SPECT in pulmonary hypertension animal models / 中华核医学与分子影像杂志

Objective:To explore the changes of right ventricular myocardial perfusion in pulmonary arterial hypertension (PAH) pig models with a quantitative analysis technique based on dynamic SPECT myocardial perfusion imaging, and analyze the relationship between myocardial blood flow, hemodynamics and right ventricular function.Methods:Eleven Chinese miniature pigs (all males, 6-8 months old) weighing 25-30 kg were selected. The PAH models were established by ligating the main pulmonary artery and embolizing the right lower pulmonary artery. After the models were established, dynamic myocardial perfusion imaging with one-day resting/adenosine stress 99Tc m-methoxyisobutylisonitrile (MIBI) SPECT was performed, and the quantitative parameters of left and right ventricles were obtained, including stress myocardial blood flow (SMBF), rest myocardial blood flow (RMBF) and myocardial flow reserve (MFR: the ratio of stress to rest myocardial blood flow). Right heart catheterization was performed to evaluate the mean pulmonary arterial pressure (mPAP), and the right heart function index tricuspid annular plane systolic excursion (TAPSE) was measured by transthoracic echocardiography. According to TAPSE, animals were divided into right heart function preserved group ( n=5, TAPSE≥17 mm) and right heart dysfunction group ( n=4, TAPSE<17 mm). Pearson correlation analysis and the independent-sample t test were used for data analysis. Results:Nine experimental pig models were established with increased mPAP of (38.1 ± 11.6 ) mmHg (1 mmHg=0.133 kPa). Myocardial perfusion imaging showed clear radiotracer uptake in the right heart and myocardial hypertrophy. There was a significant positive correlation between right ventricular myocardial RMBF ((0.71±0.13) ml·min -1·g -1) and mPAP ( r=0.94, P< 0.001). The SMBF in the decreased right ventricular function group was significantly lower than that in the preserved right ventricular function group ((1.66±0.35) vs (2.24±0.30) ml·min -1·g -1;t=2.68, P=0.032). Conclusion:SPECT myocardial blood flow quantification can be used to evaluate the right ventricular myocardial blood flow in pig models of PAH.

Value of SPECT myocardial perfusion imaging and coronary flow reserve combined with coronary artery calcium score in the diagnosis of obstructive coronary artery disease / 中华核医学与分子影像杂志

Objective:To study the value of myocardial perfusion imaging (MPI) and coronary flow reserve (CFR) combined with coronary artery calcium score (CACS) in the diagnosis of obstructive coronary artery disease (CAD).Methods:From January 2019 to December 2020, 96 confirmed or suspective CAD patients (65 males, 31 females; age: 30-81 years) who completed rest/stress MPI, CFR and CACS defection in Fuwai Central China Cardiovascular Hospital were retrospectively analyzed. Coronary angiography (CAG) was used as the diagnostic standard to calculate the sensitivity and accuracy of MPI, CFR and MPI/CFR combined with CACS in the diagnosis of CAD. The χ2 test was used to compare the diagnostic efficiency of different methods. Results:The diagnostic sensitivity of MPI was 76.06%(54/71), and the accuracy was 75.00%(72/96), while the sensitivity increased to 97.18%(69/71; χ2=13.67, P<0.001) and the accuracy increased to 87.50%(84/96; χ2=4.92, P=0.020) with significant differences after combined with CACS. The sensitivity and accuracy of CFR were 91.55%(65/71)and 87.50%(84/96), which increased to 97.18%(69/71; χ2=2.12, P=0.137) and 89.58%(86/96; χ2=0.21, P=0.411) with no significant differences after combined with CACS. The sensitivity of MPI in the diagnosis of three-vessel CAD was 70.00%(21/30), which increased to 100%(30/30; χ2=7.75, P=0.004) after combined with CACS; while the sensitivity of MPI combined with CACS in the diagnosis of single-vessel and double-vessel CAD were not significantly improved ( χ2 values: 3.29, 1.51, P values: 0.114, 0.416). Conclusion:The combination of MPI and CACS can significantly improve the diagnostic efficiency of CAD, contributed by the improvement of the diagnostic sensitivity in three-vessel disease; whereas the diagnostic efficiency of CFR for CAD is not significantly improved after combined with CACS.

Establishment of the normal reference values of left ventricular function parameters evaluated by CZT SPECT stress gated myocardial perfusion imaging in low-likelihood of stable coronary artery disease / 中华核医学与分子影像杂志

Objective:To establish the normal reference value of left ventricular function parameters by cadmium-zinc-tellurium (CZT) SPECT stress gated myocardial perfusion imaging (G-MPI) in low-likelihood of stable coronary artery disease (SCAD).Methods:From March 2022 to August 2022, 348 consecutive SCAD patients (146 males, 202 females, age (58±10) years) who underwent exercise or pharmacological stress G-MPI (CZT SPECT) in Beijing Anzhen Hospital, Capital Medical University were retrospectively recruited. Left ventricular end-diastolic volume (EDV), end-systolic volume (ESV), and left ventricular ejection fraction (LVEF) were acquired using quantitative gated SPECT (QGS) analysis. EDV and ESV were corrected by body surface area (BSA) to obtain EDV index (EDVI) and ESV index (ESVI), respectively. Independent-sample t test, one-way analysis of variance and Mann-Whitney U test were used for data analysis. The influences of EDV, ESV, EDVI, ESVI and LVEF were analyzed by multiple regressions for linear models. Results:There were 314 patients with low-likelihood of SCAD (128 males, 186 females, age (58±10) years) and 34 normal controls (18 males, 16 females, age (55±10) years). There were no significant differences of basic clinical characteristics and left ventricular function parameters in different genders between 2 groups ( z values: from -1.74 to -0.02, t values: from -1.16 to 1.17, all P>0.05). Using the 95% CI as the cut-off value for left ventricular function parameters in patients with a low-likelihood of SCAD, the upper limits of EDV, ESV, EDVI and ESVI in females and males were 84 and 111 ml, 30 and 44 ml, 47 and 54 ml/m 2, 17 and 21 ml/m 2, respectively, and the lower limit of LVEF in females and males were 58% and 55%, respectively. In the low-likelihood of SCAD group, the EDV ((58±13) vs (77±17) ml) and ESV ((16±7) vs (26±9) ml) of females were smaller than those of males ( t values: 10.65, 10.35, both P<0.001), while LVEF of females was higher than that of males ((72±7)% vs (67±6)%; t=-6.23, P<0.001). However, there were no significant differences in left ventricular function parameters among different age groups with the same gender ( F values: 0.12-2.19, all P>0.05). Based on multiple regression for linear models, the primary predictors of EDV, ESV and LVEF were gender and weight ( β values: from -0.380 to 0.358, all P<0.05). Conclusions:Normal reference values of left ventricular function parameters are established by CZT SPECT stress G-MPI in low-likelihood of SCAD patients. Left ventricular EDV and ESV of females are smaller than those of males, while LVEF of females is higher than that of males. The influence of gender on left ventricular function parameters should be considered in clinical practice.

Exploring risk factors for combined coronary microvascular dysfunction in patients with ischemia and non-obstructive coronary artery disease / 中华核医学与分子影像杂志

Objective:To investigate the risk factors for combined coronary microvascular dysfunction (CMD) in patients with ischemia and non-obstructive coronary artery disease (INOCA).Methods:From October 2020 to May 2022, 100 INOCA patients with myocardial ischemic symptoms who underwent coronary angiography (CAG) suggestive of <50% stenosis in all three coronary arteries at the Tenth People′s Hospital of Tongji University were prospectively recruited. Myocardial perfusion imaging (MPI), transthoracic echocardiography and cadmium-zinc-telluride (CZT) SPECT coronary flow quantification were performed in the same month, and 93 INOCA patients (36 males and 57 females, age (63.0±10.9) years) were finally included. CMD was defined as coronary flow reserve (CFR)<2.5. Independent-sample t test, Mann-Whitney U test and χ2 test were used to compare MPI results and left ventricular volume parameters between CMD and non-CMD groups. ROC curve analysis was used to analyze the efficacy of each index in predicting CMD, and independent risk factors for CMD were screened by multivariate logistic regression analysis. Results:Among 93 INOCA patients, 29 were in the CMD group and 64 were in the non-CMD group. The age, proportion of hypertension, left ventricular mass index (LVMI), summed stress score (SSS), summed difference score (SDS), left ventricular internal diameter systolic (LVIDS), interventricular septum thickness (IVST), and left ventricular posterior wall thickness (LVPWT) in the CMD group were higher than those in the non-CMD group ( t values: 2.42-3.76, χ2=8.94, z values: -3.31, -3.41, all P<0.05). ROC curve analysis showed that LVMI, SSS, SDS, LVPWT, IVST and age were significant in predicting CMD (AUCs: 0.67-0.72). Multivariate logistic regression analysis showed that LVMI (odds ratio ( OR)=1.08, 95% CI: 1.01-1.17), SDS ( OR=5.37, 95% CI: 1.95-14.78), hypertension ( OR=5.68, 95% CI: 1.34-24.18) and age ( OR=1.10, 95% CI: 1.03-1.18) were risk factors for CMD. Conclusion:LVMI, SDS, hypertension and age are strongly associated with combined CMD in INOCA patients, which can be used for early risk stratification of INOCA patients.

Relationship between coronary flow reserve by CZT SPECT and invasive coronary fractional flow reserve and its potential clinical value / 中华核医学与分子影像杂志

Objective:To evaluate the relationship between regional coronary flow reserve (CFR) obtained from cadmium-zinc-telluride SPECT(CZT SPECT) myocardial functional perfusion imaging (MFPI) and invasive fractional flow reserve (FFR) measured during coronary angiography (CAG) and its clinical value in guiding coronary interventions.Methods:Forty-two patients (30 males, 12 females, age (63.3±9.8) years) who completed CZT SPECT MFPI in the First Affiliated Hospital of Nanjing Medical University from June 2022 to September 2022 and underwent CAG within 3 months were included retrospectively. The concordance of CFR and FFR for diagnosing myocardial ischemia (CFR<2.0 and FFR<0.8) was calculated at the vascular level. The diagnostic efficacy of coronary stenosis≥70% for decreased myocardial blood flow (CFR<2.0) was calculated. Kappa test was used to analyze the data. Results:A total of 126 major coronary arteries were identified in 42 patients, of which 30(23.8%) had a CFR<2.0 by CZT SPECT and 33(26.2%) had stenosis≥70% in CAG. A total of 32 coronary vessels were performed with MFPI CFR and FFR measurements, of which 6 were both decreased and 21 were both normal, so the concordance rate was 84.4%(27/32)( Kappa=0.612, P<0.001). Among 33 coronary vessels with stenosis≥70%, 13 were with CFR≥2.0. Among 30 coronary vessels with CFR<2.0, 10 were with stenosis<70%. When using stenosis≥70% to diagnose CFR decreasing, the sensitivity was 66.7%(20/30), specificity was 86.5%(83/96), positive predictive value was 60.6%(20/33), negative predictive value was 89.2%(83/93), and accuracy was 81.7%(103/126). Conclusions:The concordance between CFR and FFR for the diagnosis of myocardial ischemia is good. Nearly 1/3 of the coronary arteries with decreased CFR have stenosis<70%, whereas nearly 40% of the coronary arteries with stenosis≥70% are not result in myocardial ischemia. Regional CFR determined by CZT SPECT may have potentially significant clinical value in the diagnosis of coronary artery disease and decision-making of coronary intervention.

Diagnostic value of ATP stress myocardial perfusion imaging in detecting coronary artery disease with quantitative coronary angiography as the gold standard / 中华核医学与分子影像杂志

Objective:To assess the diagnostic value of ATP stress myocardial perfusion imaging(MPI) in detecting coronary heart disease (CAD) with quantitative coronary angiography (QCA) as the gold standard.Methods:A total of 95 consecutive patients (65 males, 30 females, age (56.2±8.5) years) who underwent ATP stress/rest MPI and coronary angiography (CAG) within one month in Fuwai Hospital, Chinese Academy of Medical Sciences from May 2018 to December 2018 were enrolled prospectively. The adverse reactions of ATP stress test were observed. Semi-quantitative analysis was performed on MPI results, and the summed stress score (SSS), summed rest score (SRS) and summed difference score (SDS) were obtained. Quantitative analysis was performed on CAG images, and the degree of QCA coronary artery stenosis was analyzed. Using QCA as the gold standard, the diagnostic efficiency of ATP stress MPI was calculated. Pearson correlation analysis was performed to analyzed the relationship between SSS and the degree of QCA coronary artery stenosis.Results:In 95 cases, the incidence of adverse reactions in ATP stress test was 73.7%(70/95), which could be relieved automatically after drug withdrawal. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of ATP stress MPI in diagnosing coronary artery stenosis ≥50% were 45.3%(24/53), 81.0%(34/42), 75.0%(24/32), 54.0%(34/63) and 61.1%(58/95) respectively, which were 15/16, 78.5%(62/79), 46.9%(15/32), 98.4%(62/63), and 81.1%(77/95) respectively in diagnosing coronary artery stenosis ≥70%. There was moderate correlation between SSS and the degree of QCA coronary artery stenosis ( r=0.418, P=0.017). Conclusion:ATP stress MPI has a clinical value in the diagnosis of myocardial ischemia in CAD.

The comparison of anatomical and functional features between patients with ischemic with non-obstructive coronary artery disease and obstructive coronary artery disease by CT / 中华放射学杂志

Objective:To explore the difference of the vessel and plaque characteristics, myocardial perfusion and cardiac function between patients with ischemia with non-obstructive coronary artery disease (INOCA) and obstructive coronary artery disease (CAD).Methods:From July 2021 to June 2022, 101 patients with angina were referred to dynamic computed tomography myocardial perfusion (CTP) and coronary computed tomography angiography (CCTA) and retrospectively included in our hospital. Based on the results of CTP and CCTA, patients were divided into INOCA (27 cases), moderate obstructive CAD (26 cases) and severe obstructive CAD (48 cases). The anatomical coronary artery stenosis, plaque characteristics and myocardial perfusion features of all patients were analyzed. Furthermore, left ventricular global longitudinal strain (GLS), global circumferential strain (GCS), and global radial strain (GRS) were obtained on full-phase reconstruction CCTA image by using Medis Suite 3.2 postprocessing software. Multigroup analysis used one way ANOVA or Kruskal Wallis H test. Results:Patients with INOCA were younger than patients with moderate and severe obstructive CAD ( P<0.001). INOCA patients (7.4%, 2/27) had lower rate of positive remodeling than both moderate (57.7%, 15/26, P<0.001) and severe obstructive CAD patients (33.3%, 16/48, P=0.017). The percentage of ischemic myocardium volume in patients with INOCA were similar with those in patients with severe CAD (all P>0.05), but significantly higher than those in patients with moderate CAD (all P<0.05). No significant difference in terms of GLS was detected between patients with INOCA [-17.4% (-21.6%, -11.6%)] and severe CAD [-17.6% (-21.9%, -14.8%), P=0.536], however, patients both with INOCA and severe CAD also had higher GLS than patients with moderate obstructive CAD [-22.3% (-29.8%, -19.0%), all P<0.05]. Conclusions:Based on"one-stop-shop"CTP combined with CCTA imaging, early cardiac functional changes including abnormal myocardial perfusion and myocardial strain in INOCA patients were similar to those in patients with severe obstructive CAD and more severe than those in patients with moderate obstructive CAD.

Construction of a porcine model of ischemia with non-obstructive coronary artery and assessment by CT myocardial perfusion imaging combined with coronary CT angiography / 中华放射学杂志

Objective:To construct a porcine model of ischemia with non-obstructive coronary artery (INOCA) and explore the diagnostic value of a one-stop noninvasive method including CT myocardial perfusion imaging (CT-MPI) and coronary CT angiography (CCTA).Methods:Twelve swines were divided into the experimental group (9) and the normal group (3). Coronary microvascular dysfunction (CMD) porcine model was constructed in the experimental group by inducing diabetes mellitus, chronic kidney disease, and hypercholesterolemia. Invasive coronary angiography (ICA) and functional examination were performed on all 7+3 trial swines to clarify the INOCA diagnosis after completion of the modeling. Then, CT-MPI and CCTA were performed on all individuals to explore the CT-MPI and CCTA characteristics of INOCA porcine models. CT-MPI parameters, including myocardial blood flow (MBF), and myocardial blood volume (MBV) in rest and stress conditions, and CCTA parameters, including severity of stenosis and CAD-RADS, were analyzed.Results:ICA and functional tests showed that all swines in the experimental group met the diagnostic criteria for INOCA, which meant that INOCA porcine model was constructed successfully. CCTA results confirmed that there was no obstructive coronary stenosis in all 10 swines which were examined, which was consistent with ICA findings. CT-MPI results demonstrated that the mean MBF values, as well as the mean MBV values, in the rest and stress condition of each swines in the experimental group were lower than those of the control group. In contrast to the control group, the mean MBF and MBV values of swines in the experimental group in stress condition were generally lower than those in resting condition.Conclusions:In this study, a porcine model of CMD is successfully constructed by inducing hypercholesterolemia+diabetes mellitus+chronic kidney disease. ICA and invasive functional tests show that this CMD model meet the diagnostic criteria for INOCA. It has been confirmed that one-stop CT multimodality examination including CT-MPI and CCTA can be used for the diagnosis of INOCA as a noninvasive diagnostic method.

Diagnostic value of cardiac magnetic resonance contrast medium perfusion and delayed contrast enhancement for early myocardial ischemia / 中国基层医药

Objective:To investigate the diagnostic value of cardiac magnetic resonance (CMR) contrast medium perfusion and delayed contrast enhancement for early myocardial ischemia.Methods:Ninety-one patients with coronary artery stenosis diagnosed by coronary angiography (CAG) between March 2020 and March 2022 in Yiwu Central Hospital were included in this study. These patients underwent first-pass perfusion cardiac magnetic resonance imaging and delayed enhancement examination. Arrival time ( t0), accumulative signal intensity (ASI), relative peak enhancement rate (SI%), maximum intensity of signal enhancement (SIp), and maximum curve slope (α) were statistically analyzed in the CMR contrast agent normal-dose perfusion and low-dose perfusion segments. The diagnostic value of CMR contrast agent perfusion versus CAG for early myocardial ischemia was determined. The signal intensity was compared between enhanced and non-enhanced areas of CMR contrast agent perfusion. Results:There were significant differences in ASI, SI%, SIp, and Slope (α) between normal perfusion and low perfusion segments ( t = 9.62, 10.65, 8.67, 6.93, all P < 0.05). There was no significant difference in the detection rate of lesioned vessels in early myocardial ischemia between CMR contrast agent perfusion and CAG [50.42% (120/238) vs. 51.68% (123/238), χ2 = 1.32, P = 0.163). There was a significant difference in the detection rate of lesioned vessels in myocardial ischemia between CMR contrast agent perfusion and CAG ( χ2 = 15.31, P < 0.001, r = 0.71). The signal intensity value in the delayed enhancement segment was significantly higher than that in the non-delayed enhancement segment [(598.43 ± 40.19) vs. (298.64 ± 70.58), t =19.85, P = 0.001). Conclusion:CMR contrast agent perfusion can effectively evaluate the severity of early myocardial ischemia and locate the diseased blood vessels. Delayed enhancement can determine the location and area of early myocardial ischemia, and can objectively reflect the severity of myocardial ischemia.

CT myocardial perfusion imaging complementing coronary CT angiography in a patient with a history of unstable angina: A case report

Coronary computed tomography angiography (CCTA) could show the morphological status of coronary stenosis. Moreover, computed tomography (CT) myocardial perfusion (CTP) could provide additional information to identify hypoattenuating areas that might complement the limitation of CCTA in terms of evaluating the functional status, adding to the diagnostic performance of CCTA. We reported the imaging features of coronary artery disease in a female patient with a history of unstable angina by evaluating the anatomic and functional information through CCTA and CT myocardial perfusion in one stop modality

Comparison between Bruce and ramp protocols for exercise testing in the diagnosis of myocardial ischemia

BACKGROUND: Exercise tests are an important tool in the investigation of myocardial ischemia. The ramp protocol has gained increasing importance in clinical practice because of the possibility of individualizing its exercise intensity. OBJECTIVE: To assess and compare the sensitivity, specificity, and accuracy of Bruce and ramp protocols for exercise testing in the diagnosis of myocardial ischemia considering myocardial perfusion scintigraphy as the reference standard. Secondary objectives included the assessment of hemodynamic profiles, functional capacity, and the incidence of arrhythmias in each of the protocols. METHODS: Participants underwent exercise testing using the ramp and Bruce protocols, and the tests' diagnostic power was assessed. For testing the difference between data provided by both protocols, we used a paired Student's t-test or Wilcoxon test, depending on the assumption of data normality. The level of significance adopted for all tests was 5%. RESULTS: The ramp protocol showed sensitivity, specificity, and accuracy values of 55.6%, 82.4%, and 76.7%, respectively, whereas the Bruce protocol had results of 77.8%, 64.7%, and 67.4%, respectively. The maximum heart rate and double product at peak exercise were significantly higher in the Bruce protocol (p = 0.043 and p = 0.040, respectively). No differences were observed between the incidence of arrhythmias in both protocols. CONCLUSION: The Bruce protocol presented higher sensitivity for detecting ischemia on the exercise test, while the ramp protocol presented higher specificity and accuracy.

Predictive value of CT perfusion imaging on the outcome after mechanical thrombectomy in patients with anterior circulation large vessel occlusive stroke / 国际脑血管病杂志

Objective:To investigate the predictive value of CT perfusion imaging (CTP) parameters on the outcome after mechanical thrombosis (MT) in patients with anterior circulation acute ischemic stroke due to large vessel occlusion (LVO-AIS).Methods:The clinical data of patients with LVO-AIS received MT treatment in Taizhou People’s Hospital from July 2019 to June 2021 and achieved modified Thrombolysis in Cerebral Infarction (mTICI) blood flow grade 2b or above were retrospectively enrolled. RAPID software was used to automatically conduct image post-processing to obtain CTP parameters. The patients were divided into good outcome group (≤2) and poor outcome group (>2) according to the modified Rankin Scale score at 90 days after procedure. Multivariate logistic regression analysis was used to screen the CTP parameters that affect the outcomes. The receiver operating characteristic (ROC) curve was used to evaluate the predictive value of CTP parameters for poor outcomes. Results:A total of 88 patients with LVO-AIS were enrolled, including 52 males (59.1%), with a median age of 71 years (range 58-78 years), and the median baseline National Institutes of Health Stroke Scale (NIHSS) score of 14 (range, 11-17). Eleven patients (12.5%) received intravenous thrombolytic bridging MT, and 77 (87.5%) received direct MT. Forty-seven patients (53.4%) had good outcomes and 41 (46.6%) had poor outcomes at 90 d after procedure. Univariate analysis showed that there were significant differences in baseline NIHSS score, vascular occlusion site, baseline Alberta Stroke Program Early CT Score, the number of retrieval attempts, V CBF<30%, V Tmax>6 s, V CBF>30%/mismatch volume and hypoperfusion intensity ratio (HIR) between the poor outcome group and the good outcome group (all P<0.05). Multivariable logistic regression analysis showed that atrial fibrillation (odds ratio [ OR] 6.200, 95% confidence interval [ CI] 1.225-31.374; P=0.027), baseline NIHSS score ( OR 1.188, 95% CI 1.00-1.404; P=0.043) and V CBF<30% ( OR 1.079, 95% CI 1.03-1.123; P=0.027) were the independent influencing factors of poor outcomes. ROC curve analysis showed that the areas under the curve of atrial fibrillation, baseline NIHSS score, V CBF<30% and their combined for predicting the poor outcoms were 0.675, 0.739, 0.882 and 0.914, respectively. V CBF<30% had the highest diagnostic efficiency in predicting poor outcomes of the single factor. When the cutoff value was 16 ml, the sensitivity and specificity were 82.9% and 78% respectively. Conclusions:RAPID software analysis parameters based on CTP can be used to predict the clinical outcomes after MT in patients with LVO-AIS. V CBF<30% >16 ml has a higher predictive value for poor outcomes after MT.