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.

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.

Índices fisiológicos não hiperêmicos ­ base teórica, aplicações clínicas e limitações / Non-hyperemic pressure ratios ­ theoretical basis, clinical applications, and limitations

A fisiologia coronariana tornou-se o padrão de tratamento para avaliar o significado funcional da doença aterosclerótica coronariana. Ela permite identificar isquemia miocárdica em nível de vaso, discriminar os padrões funcionais da doença aterosclerótica e orientar a necessidade de revascularização; complementar o planejamento da intervenção coronária percutânea e confirmar o sucesso funcional dessa última. Em uma edição anterior do Journal of Transcatheter Interventions, apresentamos uma revisão abrangente sobre o fluxo fracionado de reserva do miocárdio. Apesar do robusto corpo de evidências que apoiam seu uso, a aceitação clínica do fluxo fracionado de reserva é variável e excessivamente baixa em muitas áreas do mundo. O aumento percebido no tempo do procedimento, o uso de agentes hiperêmicos com seus correspondentes custos e desconforto do paciente, e a dificuldade de interpretação dos resultados em determinadas situações anatômicas contribuíram para a adoção limitada do método. A introdução do índice de fluxo instantâneo no período livre de ondas superou a maioria dessas limitações. Apoiada por uma validação técnica sólida e dados de desfechos clínicos, o índice de fluxo instantâneo no período livre de ondas recebeu as mesmas indicações clínicas que o fluxo fracionado de reserva nas recomendações mais recentes das diretrizes. Isso foi seguido pela introdução de outros índices pressóricos não hiperêmicos, já comercialmente disponíveis. Neste artigo, revisamos as bases fisiológicas que justificam o uso de índices pressóricos não hiperêmicos, sua validação técnica e clínica e dados de desfechos clínicos, além de discutirmos suas aplicações em situações anatômicas específicas, com exemplos de casos dos autores, sempre que aplicável.

Coronary physiology has become the standard of care to assess the functional significance of coronary atherosclerotic disease. It allows for identification of myocardial ischemia on a vessel level, discrimination of the functional patterns of atherosclerotic disease, guidance for the need of revascularization, complements the planning of percutaneous coronary intervention and verification of the functional success of percutaneous coronary intervention. On a previous issue of the Journal of Transcatheter Interventions, we presented a comprehensive review about fractional flow reserve. Despite the robust body of evidence supporting its use, the clinical use of fractional flow reserve is variable, and unreasonably low in many areas around the globe. The perceived increase in procedure time, the use of hyperemic agents with its related costs and patient discomfort, and difficulty in interpreting results in certain anatomical scenarios have contributed to the limited adoption of fractional flow reserve. The introduction of instantaneous wave-free ratio overcame most of these limitations. Supported by sound technical validation, and clinical outcomes data, instantaneous wave-free ratio received the same clinical indications as fractional flow reserve in the most recent guidelines recommendations. This was followed by the introduction of other non- hyperemic pressure ratios for commercial use. In the current manuscript we review the physiological basis that supports the use of non-hyperemic pressure ratios, their technical and clinical validation, clinical outcomes data, and discuss its applications on specific anatomic scenarios, with examples of cases from the authors, whenever applicable.

Fluxo fracionado de reserva do miocárdio: bases fisiológicas, aplicações clínicas e limitações / Fractional flow reserve: physiological bases, clinical applications and limitations

A avaliação fisiológica invasiva da circulação coronariana emergiu nos últimos anos como uma abordagem diagnóstica valiosa no manejo de pacientes com síndrome coronariana crônica, contornando limitações importantes como avaliar função a partir da anatomia e a baixa resolução espacial associada à angiografia ou testes não invasivos. O valor das medidas de fluxo hiperêmico para estimar a relevância funcional das estenoses coronárias é suportado por um grande número de estudos. O objetivo do presente artigo é rever as principais bases fisiológicas, aplicações clínicas e limitações do fluxo fracionado de reserva do miocárdio, o principal índice utilizado na avaliação funcional invasiva da circulação coronariana.

Invasive physiological assessment of the coronary circulation has emerged in recent years as a valuable diagnostic approach in the management of patients with chronic coronary syndrome, overcoming important limitations such as evaluating function from the anatomy and the low spatial resolution associated with angiography or non-invasive tests. The value of hyperemic flow measurements to estimate the functional relevance of coronary stenoses is supported by many studies. The aim of this paper is to review the physiological bases, clinical applications and limitations of myocardial fractional flow reserve, the main index used in the invasive functional assessment of the coronary circulation.

Valoración de la reserva contráctil y cronotrópica en estudios de eco estrés negativos para isquemia miocárdica / Contractile and chronotropic reserve assessment in stress echocardiography studies negative for myocardial ischemia

RESUMEN Introducción: Si bien el principal objetivo del ecocardiograma estrés (EE) es analizar los cambios en la motilidad parietal, el análisis de otras variables como la reserva contráctil (RCon) por el método de elastancia y la reserva cronotrópica (RCro) permiten agregar valor pronóstico al estudio. No obstante, las mismas no suelen analizarse ni informarse en la mayoría de los estudios de EE en nuestro medio. Objetivos: Comparar las características clínicas y ecocardiográficas de pacientes a quienes se les realizó un EE con ejercicio negativo para isquemia miocárdica de acuerdo con la presencia o no de RCon y RCro. Material y métodos: Estudio retrospectivo realizado sobre 73 pacientes con EE con ejercicio, sin isquemia. De acuerdo con la presencia o ausencia de RCon y RCro se los dividió en tres grupos. Grupo 1: presencia de ambas reservas; grupo 2: presencia de solo una reserva y grupo 3: ausencia de ambas reservas. La RCon se determinó mediante el cociente entre la tensión arterial sistólica y el volumen de fin de sístole tanto en reposo como en estrés (Valor normal: > 2) y la RCro se definió como el aumento mayor al 80% de la frecuencia cardíaca basal. Resultados: Se incluyeron 73 pacientes (64% varones, edad 63 ± 12 años). En el Grupo 1 se incluyeron 23 pacientes (62% varones, 59,8 ± 12,5 años), en el grupo 2, 29 pacientes (65% varones, 60,7 ± 13 años) y en el grupo 3, 21 pacientes (65% varones, 68,8 ± 7,8 años). Los pacientes sin ninguna reserva fueron más añosos y presentaron una tendencia a mayor prevalencia de los factores de riesgo tradicionales, más antecedentes de IAM y mayor uso de betabloqueantes. Desde el punto de vista ecocardiográfico, este mismo grupo presentó menores valores de fracción de eyección ventricular izquierda (FEVI) y strain longitudinal global (SLG) tanto en reposo como en esfuerzo, mayor masa ventricular, y en la ergometría menor cantidad de minutos de ejercicio realizado. Se realizó una regresión logística binaria con aquellas variables asociadas a la ausencia de RCon y RCro. La edad (OR 1,12, IC95% 1,02-1,22; p = 0,01) y el valor de SLG en reposo (OR 0,68, IC95% 0,51-0,90; p= 0,008) fueron las variables asociadas en forma independiente a la ausencia de ambas reservas. En una curva ROC, un valor de SLG de -18% fue el mejor punto de corte (área bajo la curva 0,72; IC 95% 0,57-0,87). Conclusiones: Los pacientes con EE negativo para isquemia miocárdica, y que además presentan ausencia de RCon y RCro tienen un perfil de riesgo más elevado. Esto podría estar asociado a mayor riesgo de eventos cardiovasculares durante el seguimiento.

ABSTRACT Background: While the primary objective of the stress echocardiography (stress echo) is to assess wall motion abnormalities, evaluation of other variables, such as contractile reserve (CR) via elastance, and chronotropic reserve (ChR), may add prognostic value to the study. However, these are unusually evaluated or reported in most stress echo studies in our field. Objectives: To compare clinical and echocardiographic characteristics in patients undergoing an exercise stress echo with negative results for myocardial ischemia based on the presence or absence of CR and ChR. Methods: A rRetrospective study in 73 patients, with exercise stress echo and no ischemia. Patients were divided into three groups, based on the presence or absence of CR and ChR. Group 1: presence of both; Group 2: presence of either of the two, and Group 3: absence of both. The CR was established using as the systolic blood pressure and end-systolic volume ratio, both at rest and under stress (normal value: >2), and the ChR was defined as a more than 80% increase in baseline heart rate. Results: The study enrolled 73 patients (64% males, aged 63±12 years). Group 1 included 23 patients (62% males, agedaged 59.8±12.5 years); Group 2 included 29 patients (65% males, aged 60.7±13 years), and Group 3 included 21 patients (65% males, aged 68.8±7.8 years). Patients with no reserve were older and showed a tendency to higher prevalence of traditional risk factors, a longer history of AMI and increased use of beta blockers. In the Echocardiographicallyechocardiographic study, his group had lower values of left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS) both at rest and under stress, a larger ventricular mass, and less minutes of exercise according toin the exercise stress test. A binary logistic regression was performed using variables associated with the absence of CR and ChR. Age (OR 1.12, 95% CI 1.02-1.22; p=0.01) and GLS at rest (OR 0.68, 95% CI 0.51-0.90; p=0.008) were variables independently associated with the absence of both reserves. On a ROC curve, a GLS of -18% was the best cutoff point (area under the curve 0.72). Conclusion: Patients with a stress echo negative for myocardial ischemia and absence of CR and ChR have a higher risk profile. This could be associated with a higher risk of cardiovascular events during the follow-up.

Determinação do Tecido Cicatricial do Miocárdio no Fenômeno de Fluxo Coronário Lento e a Relação entre a Quantidade de Tecido Cicatricial e o Nt-ProBNP / Determination of Myocardial Scar Tissue in Coronary Slow Flow Phenomenon and The Relationship Between Amount of Scar Tissue and Nt-ProBNP

Resumo Fundamento A fisiopatologia e o prognóstico não estão claramente determinados nos pacientes com fenômeno do fluxo coronário lento (FCL). Esses pacientes apresentam várias condições clínicas, que variam desde quadro assintomático até internação hospitalar com morte cardíaca súbita. Objetivos Nosso objetivo foi avaliar os achados da ressonância magnética cardíaca (RMC) com o realce tardio pelo gadolínio (RTG), como um indicador de fibrose miocárdica. Também buscamos determinar a relação entre a presença de fibrose miocárdica e os níveis de NT-proBNP em pacientes com FCL na artéria coronária descendente anterior esquerda (DAE). Métodos Ao todo, 35 pacientes, entre 31 e 75 anos de idade, foram incluídos. Os pacientes estudados (n=19) apresentaram artérias coronárias epicárdicas normais na angiografia, mas tinham FCL na DAE. O grupo controle de pacientes (n=16) apresentou artérias coronárias epicárdicas normais e níveis de escore TIMI normais na angiografia. Em ambos os grupos, os pacientes foram examinados com RMC para a detecção de presença de fibrose miocárdica. Além disso, níveis plasmáticos de NT-proBNP foram medidos. Valores de p < 0,05 foram considerados significativos. Resultados A taxa de fibrose miocárdica foi significativamente maior na RMC para os pacientes com FCL (p=0.018). Uma quantidade variável de tecido cicatricial foi detectada no ápice ventricular esquerdo em 7 pacientes e nas regiões inferior e inferolateral em 3 pacientes. Não foram observadas diferenças nos níveis de NT-proBNP nos pacientes com FCL. Entretanto, os níveis de NT-proBNP foram maiores nos pacientes com FCL, que apresentaram fibrose miocárdica na RMC (p=0.022). Conclusões Em suma, o RTG na RMC mostrou que a cicatriz miocárdica isquêmica pode estar presente nos pacientes com FCL. Esses resultados indicam que o FCL pode nem sempre ser inofensivo. (Arq Bras Cardiol. 2020; 114(3):540-551)

Abstract Background Pathophysiology and prognosis are not clearly determined in patients with the coronary slow flow phenomenon (CSFP). These patients present with various clinical conditions ranging from being asymptomatic to being admitted with sudden cardiac death. Objectives We aimed at assessing the findings of late gadolinium enhancement (LGE) in cardiac magnetic resonance imaging (CMR) as an indicator of myocardial fibrosis. We also aimed at determining the relationship between the presence of myocardial fibrosis and NT-proBNP levels in patients with CSFP in the left anterior descending coronary artery (LAD). Methods A total of 35 patients were enrolled within an age range of 31-75. The study patients (n=19) had normal epicardial coronary arteries at angiography, but they presented with CSFP in the LAD. The control group patients (n=16) had normal epicardial coronary arteries and TIMI scores at normal levels in angiography. In both groups, the patients were examined with CMR for the presence of myocardial fibrosis. In addition, plasma NT-proBNP levels were measured. A p-value < 0.05 was considered significant. Results The rate of myocardial fibrosis was significantly higher in CMR in the patients with CSFP (p=0.018). A variable amount of myocardial scar tissue was detected at the left ventricular apex in 7 patients and at the inferior and inferolateral regions in 3 patients. There was no difference in the level of NT-proBNP in patients with CSFP. However, the NT-proBNP levels were higher in patients with CSFP, who had scar tissue in CMR (p=0.022). Conclusions In conclusion, LGE in CMR showed that ischemic myocardial scarring may exist in patients with CSFP. These results indicate that CSFP may not always be innocent. (Arq Bras Cardiol. 2020; 114(3):540-551)

Evaluation of Myocardial Ischemia with iFR (Instantaneous Wave-Free Ratio in the Catheterization Laboratory: A Pilot Study / Avaliação de Isquemia Miocárdica na Sala de Hemodinâmica com iFR Instantaneous Wave-Free Ratio: Estudo Piloto

Abstract Background: The Instantaneous Wave-Free Ratio (iFR) is an invasive functional evaluation method that does not require vasoactive drugs to induce maximum hyperemia Objective: To evaluate the contribution of the iFR to the therapeutic decision-making of coronary lesions in the absence of non-invasive diagnostic methods for ischemia, or in case of discordance between these methods and coronary angiography. Method: We studied patients older than 18 years, of both sexes, consecutively referred for percutaneous treatment between May 2014 and March 2018. Coronary stenotic lesions were classified by visual estimation of the stenosis diameter into moderate (41-70% stenosis) or severe (71%-90%). An iFR ≤ 0.89 was considered positive for ischemia. Logistic regression was performed using the elastic net, with placement of stents as outcome variable, and age, sex, arterial hypertension, diabetes, dyslipidemia, smoking, family history, obesity and acute myocardial infarction (AMI) as independent variables. Classification trees, ROC curves, and Box Plot graphs were constructed using the R software. A p-value < 0.05 was considered statistically significant. Results: Fifty-two patients with 96 stenotic lesions (56 moderate, 40 severe) were evaluated. The iFR cut-off point of 0.87 showed a sensitivity of 0.57 and 1-specificity of 0.88, demonstrating high accuracy in reclassifying the lesions. Diabetes mellitus, dyslipidemia, and presence of moderate lesions with an iFR < 0.87 were predictors of stent implantation. Stents were used in 32% of lesions in patients with stable coronary artery disease and AMI with or without ST elevation (non-culprit lesions). Conclusion: The iFR has an additional value to the therapeutic decision making in moderate and severe coronary stenotic lesions, by contributing to the reclassification of lesions and decreasing the need for stenting.

Resumo Fundamento: Instantaneous Wave-Free Ratio (iFR) é um método de avaliação funcional invasiva sem necessidade de droga vasoativa para indução de hiperemia máxima. Objetivo: Analisar a contribuição do iFR na terapêutica das lesões coronarianas com ausência ou discrepância entre os métodos diagnósticos não invasivos para isquemia e a angiografia coronária. Método: Foram estudados pacientes consecutivos com 18 anos ou mais, ambos os sexos, no período de maio de 2014 a março de 2018, com lesões coronarianas classificadas, por medição da porcentagem de diâmetro da estenose através de estimativa visual, em estenoses moderadas (41-70%) ou graves (71%-90%). O iFR ≤ 0,89 foi considerado positivo para isquemia. Empregou-se regressão logística com elastic net, tendo como variável desfecho o emprego de stent, e variáveis independentes: idade, sexo, hipertensão arterial, diabetes, dislipidemia, tabagismo, história familiar, obesidade e infarto agudo do miocárdio (IAM) prévio. Foram construídas Árvores de Classificação, Curva Roc, e gráficos Box Plot com o software R. O valor de p < 0,05 foi considerado significativo. Resultados: Foram avaliados 52 pacientes com 96 lesões obstrutivas (56 moderadas, 40 graves). O ponto de corte do iFR de 0,87 apresentou sensibilidade de 0,57 e 1-especificidade de 0,88, demonstrando boa acurácia para a reclassificação das lesões. Diabetes mellitus, dislipidemia, e presença de lesão moderada, com iFR < 0,87 foram preditores do implante de stents. Foram empregados stents em 32% das lesões de portadores de doença arterial coronariana estável e IAM com e sem supra de ST (lesões não culpadas). Conclusão: O iFR contribui para a reclassificação das lesões e diminuição do emprego de stents, auxiliando na abordagem das lesões moderadas e severas.

Diagnostic Accuracy of a Novel On-site Virtual Fractional Flow Reserve Parallel Computing System

El comportamiento del strain longitudinal regional depende de la reserva coronaria en un análisis simultáneo durante el eco-estrés con dipiridamol / The Behavior of Regional Longitudinal Strain Depends on Coronary Flow Reserve in a Simultaneous Analysis during Dipyridamole Stress Echocardiography

RESUMEN Introducción: Está poco estudiado el comportamiento del strain longitudinal regional y global en relación al valor de la reserva coronaria. Objetivos: Comparar el comportamiento del strain longitudinal apical y global con el valor de la reserva coronaria de la arteria descendente anterior y secundariamente comparar estas respuestas con el análisis visual de la motilidad parietal durante el eco-estrés con dipiridamol. Material y métodos: Estudio retrospectivo de 179 pacientes (edad 68,7 ± 7,8), 90 hombres (50,3%). En el pico del efecto de dipiridamol, se midió la reserva coronaria, simultáneamente al strain longitudinal y el análisis visual de la contractilidad. Se organizó a los pacientes en dos grupos: grupo 1: reserva coronaria ≥ 2 y grupo 2: < 2. Strain apical se definió como el promedio de 4 segmentos apicales y global de los 17 segmentos. Se consideró normal a todo incremento del strain. Resultados: Se incluyeron 113 pacientes (63,12%) en el grupo 1 y 66 (36,87%) en el grupo 2. Strain apical: el 96,77% del grupo 1 incrementaron su valor con el apremio, mientras que, en el grupo 2, el 95,31% presentaron una caída (p < 0,0001). Strain global: el 82,8% del grupo 1 presentaron incremento de sus valores, en cambio, en el grupo 2, el 78,8% empeoraron (p < 0,01). Análisis de la motilidad parietal posdipiridamol: el 96,46% del grupo 1 tenían motilidad parietal conservada y el 54,5% del grupo 2 (solo en 4 pacientes aumentó el strain apical). Conclusiones: Se comprobó una estrecha correlación entre la reserva coronaria y el strain longitudinal. El strain longitudinal apical resultó ser superior del global. El strain apical demostró tener una mejor correlación con la reserva coronaria que con el análisis visual de la contractilidad.

ABSTRACT Background: The behavior of regional and global longitudinal strain in relation to the value of the coronary reserve is poorly studied. Objectives: Compare the behavior of the Apical and global longitudinal Strain with the value of the coronary reserve of the anterior descending artery and as a secondary aim compare these responses with the visual analysis of parietal motility during Echo Stress with Dipyridamole. Materials and methods: Retrospective study of 179 patients (age 68.7±7.8), 90 patients (50.3%) were men. At the peak of the dipyridamole effect, the coronary reserve was measured, simultaneously with the Longitudinal Strain and the visual analisis of contractility. Two groups were divided: Group 1: Coronary reserve ≥2 and Group 2: <2. Apical Strain was defined as the average of 4 apical segments and global as the average of the 17 segments. It was considered normal any increased of deformation. Results: 113 patients (63.12%) were included in Group 1 and 66 (36.87%) in Group 2. Strain Apical: 96.77% of Group 1 increased their strain values with the stress, while in group 2, 95.31% presented a worsening strain values (p<0.0001). Global Strain: 82.8% of Group 1 had an increase in their values, while in Group 2, 78.8% showed worsening (p<0.01). Post Dipyridamole parietal Motility Analysis: 96.46% of Group 1 had preserved parietal motility and only 54.5% of Group 2 (4 patients had increased apical Strain in this group). Conclusions: There was a close correlation between the coronary reserve of the anterior descending artery and the contractile reserve evaluated by regional apical longitudinal strain of the 4 apical segments, which was superior to the use of global strain. The Apical Strain showed a better correlation with ADA coronary reserve than with the visual analysis of contractility.

Clinical Outcomes and Cost-Effectiveness Analysis of FFR Compared with Angiography in Multivessel Disease Patient / Impacto Clínico e Custo-Efetividade da FFR em Comparação à Angiografia em Pacientes com Doenças Multiarteriais Submetidos à ICP

Abstract Background: In multivessel disease patients with moderate stenosis, fractional flow reserve (FFR) allows the analysis of the lesions and guides treatment, and could contribute to the cost-effectiveness (CE) of non-pharmacological stents (NPS). Objectives: To evaluate CE and clinical impact of FFR-guided versus angiography-guided angioplasty (ANGIO) in multivessel patients using NPS. Methods: Multivessel disease patients were prospectively randomized to FFR or ANGIO groups during a 5 year-period and followed for < 12 months. Outcomes measures were major adverse cardiac events (MACE), restenosis and CE. Results: We studied 69 patients, 47 (68.1%) men, aged 62.0 ± 9.0 years, 34 (49.2%) in FFR group and 53 (50.7%) in ANGIO group, with stable angina or acute coronary syndrome. In FFR, there were 26 patients with biarterial disease (76.5%) and 8 (23.5%) with triarterial disease, and in ANGIO, 24 (68.6%) with biarterial and 11 (31.4%) with triarterial disease. Twelve MACEs were observed - 3 deaths: 2 (5.8%) in FFR and 1 (2.8%) in ANGIO, 9 (13.0%) angina: 4(11.7%) in FFR and 5(14.2%) in ANGIO, 6 restenosis: 2(5.8%) in FFR and 4 (11.4%) in ANGIO. Angiography detected 87(53.0%) lesions in FFR, 39(23.7%) with PCI and 48(29.3%) with medical treatment; and 77 (47.0%) lesions in ANGIO, all treated with angioplasty. Thirty-nine (33.3%) stents were registered in FFR (0.45 ± 0.50 stents/lesion) and 78 (1.05 ± 0.22 stents/lesion) in ANGIO (p = 0.0001), 51.4% greater in ANGIO than FFR. CE analysis revealed a cost of BRL 5,045.97 BRL 5,430.60 in ANGIO and FFR, respectively. The difference of effectiveness was of 1.82%. Conclusion: FFR reduced the number of lesions treated and stents, and the need for target-lesion revascularization, with a CE comparable with that of angiography.

Resumo Fundamentos: Em pacientes multiarteriais e lesões moderadas, a reserva de fluxo fracionada (FFR) avalia cada lesão e direciona o tratamento, podendo ser útil no custo-efetividade (CE) de implante de stents não farmacológicos (SNF). Objetivos: Avaliar CE e impacto clínico da angioplastia + FFR versus angioplastia + angiografia (ANGIO), em multiarteriais, utilizando SNF. Métodos: pacientes com doença multiarteriais foram randomizados prospectivamente durante ±5 anos para FFR ou ANGIO, e acompanhados por até 12 meses. Foram avaliados eventos cardíacos maiores (ECAM), reestenose e CE. Resultados: foram incluídos 69 pacientes, 47(68,1%) homens, 34(49,2%) no FFR e 35(50,7%) no ANGIO, idade 62,0 ± 9,0 anos, com angina estável e Síndrome Coronariana Aguda estabilizada. No FFR, havia 26 com doença (76,5%) biarterial e 8 (23,5%) triarterial, e no grupo ANGIO, 24(68,6%) biarteriais e 11(31,4%) triarteriais. Ocorreram 12(17,3%) ECAM - 3(4,3%) óbitos: 2(5,8%) no FFR e 1(2,8%) no ANGIO, 9(13,0%) anginas, 4(11,7%) no FFR e 5(14,2%) no ANGIO, 6 reestenoses: 2(5,8%) no FFR e 4 (11,4%) no ANGIO. Angiografia detectou 87(53,0%) lesões no FFR, 39(23,7%) com ICP e 48(29,3%) com tratamento clínico; e 77(47,0%) lesões no ANGIO, todas submetidas à angioplastia. Quanto aos stents, registrou-se 39(33,3%) (0,45 ± 0,50 stents/lesão) no FFR e 78(66,6%) (1,05 ± 0,22 stents/lesão) no ANGIO (p = 0,0001); ANGIO utilizou 51,4% a mais que o FFR. Análise de CE revelou um custo de R$5045,97 e R$5.430,60 nos grupos ANGIO e FFR, respectivamente. A diferença de efetividade foi 1,82%. Conclusões: FFR diminuiu o número de lesões tratadas e de stents e necessidade de revascularização do vaso-alvo, com CE comparável ao da angiografia.

Diagnostic evaluation of CT?based non?invasive fractional flow reserve in coronary artery lesions with calcification / 中华放射学杂志

Objective To analyze the correlation between calcification factors and fractional flow reserve derived from CT (CT?FFR). And to evaluate the diagnostic efficacy of CT?FFR in coronary artery lesions with calcification compared with that of invasive FFR. Methods Sixty?five patients (74 coronary artery vessels) who were admitted to Beijing Anzhen Hospital from July 2014 to December 2016 were included in this study retrospectively. All patients had completed CCTA (coronary CT angiography), coronary angiography and invasive FFR measurements, and had coronary lesions contain calcifications. The evaluation of CCTA data included quantitative analyses of plaque components, coronary artery stenosis, and CT?FFR measurements. The patients′basic data were grouped and compared according to the FFR values. The measurement data was tested by independent?samples t tests, and the categorical data were analyzed by χ2 tests. Quantitative measurements of plaques were compared between groups using independent?sample t tests or rank sum tests based on FFR and CT?FFR values. The reproducibility of CT?FFR measurement software was evaluated by inter?class correlation coefficient (ICC) and the Youden index was calculated to determine the threshold for CT?FFR diagnosis of ischemia. Pearson or Spearman correlation analyses were used to assess the correlations between CT plaque quantitative indicators, CT?FFR and invasive FFR. Multivariate logistic regression analysis was used to analyze the predictors of ischemia by FFR and CT?FFR. In contrast to invasive FFR results, the sensitivity, specificity, negative predictive value, positive predictive value (PPV) of CT?FFR in the diagnosis of coronary ischemic lesions were evaluated, and the diagnostic consistency was evaluated by the Bland?Altman method. Results Compared with invasive FFR, CT?FFR had a more significant correlation with calcification volume and ratio of calcification in plaques (r=-0.519 and－0.547, respectively, both P=0.001). Multivariate logistic regression analysis showed that plaque length was a predictor of invasive FFR in the diagnosis of pathological ischemia ( OR=1.13, 95%CI : 1.05—1.23, P=0.002), and was associated with CT?FFR to determine pathological ischemia. In addition to plaque length ( OR=1.10, 95%CI : 1.02—1.18, P=0.010), the predictor also included ratio of calcification in plaque ( OR=1.09, 95%CI: 1.03—1.15, P=0.003). Compared with invasive FFR results, the diagnostic sensitivity of CT?FFR was 79.1%, the specificity was 80.6%, the PPV was 85.0%, and the area under the ROC curve was 0.78. The result for the diagnosis of ischemia lesion by using CT?FFR had significant statistical differences with the results by according coronary artery stenosis (χ2=10.05, P=0.002; χ2=34.71, P=0.001; χ2=7.65, P=0.006; Z=2.10, P=0.029). The Bland?Altman analysis showed a mean difference of －0.01 (-0.26—0.25) between the CT?FFR and the invasive FFR. Conclusions There is no significant correlation between the proportion of calcification components of coronary plaque and the presence or absence of myocardial ischemia, but the proportion of calcification in plaque will affect the result that is evaluated by CT?FFR. However, compared with CT?based stenosis evaluation, CT?FFR can still significantly improve the ability of CCTA to diagnose ischemia lesion with calcification.

Incremental value of coronary flow reserve assessed by CZT-SPECT in the diagnosis of coronary ar-tery disease / 中华核医学与分子影像杂志

Objective To investigate the incremental value of coronary flow reserve ( CFR) as-sessed by cadmium zinc telluride(CZT)-SPECT as an adjunct to myocardial perfusion imaging (MPI) in the diagnosis of coronary artery disease (CAD). Methods Data of 132 patients (89 males, 43 females; 40-81 years) with or suspected with CAD who successfully underwent rest and stress MPI and CFR from November 2017 to October 2018 in Zhongshan Hospital Affiliated to Fudan University were retrospectively analyzed. Based on coronary angiography (CAG) as the " gold standard" , the value of MPI and MPI+CFR in the di-agnosis of CAD was evaluated and compared. χ2 test or Fisher exact probability test was used for data analy-sis. Results Of 132 patients, 61 (46.2％) were CAD with stenosis of at least 75％ in one vessel (47.5％, 29/ 61), two vessels (34.4％, 21/ 61), or three vessels (18.0％, 11/ 61). A total of 104 (26.3％) vessels with stenosis of at least 75％, 25 (6.3％) vessels with stenosis of 65％-74％, and 30 (7.6％) vessels with stenosis of 50％-64％ were found in 396 vessels. For detecting coronary stenosis of at least 75％, the sensi-tivity and accuracy of MPI on per-patient analysis were 86.89％(53/ 61) and 68.94％(91/ 132), which in-creased to 96.72％(59/ 61; χ2 = 3.921, P<0.05) and 87.88％(116/ 132; χ2 = 13.984, P<0.01) by MPI+CFR. On per-vessel analysis, the sensitivity and accuracy of MPI were 72.12％ (75/ 104) and 77. 53％(307/ 396) and increased to 96.15％(100/ 104; χ2 = 22. 511, P<0.01) and 85.10％(337/ 396; χ2 = 7.479, P<0.05) by MPI+CFR. The sensitivity of MPI for predicting one, two, and three vessels disease were 72. 41％(21/ 29), 42.86％ (9/ 21), and 5/ 11 and were improved to 93.10％ (27/ 29; χ2 = 4.350, P =0. 037), 90.48％(19/ 21; χ2 = 10.714, P = 0.001), and 11/ 11 (P = 0.012) by MPI+CFR. For coronary with stenosis of 65％-74％, the sensitivity of MPI was 24. 00％(6/ 25) and was improved to 64.00％(16/25; χ2 = 8.117, P= 0.004) by MPI+CFR. For coronary with stenosis of 50％-64％, the sensitivity of MPI was 40.00％(12/ 30) and was improved to 76.67％(23/ 30; χ2 = 8.297, P= 0.004) by MPI+CFR. Conclu-sion As an adjunct to MPI, CFR can significantly improve the sensitivity and accuracy in the diagnosis of CAD, particularly for patients with mild stenosis and multivessel CAD.

Diagnostic value of blood flow reserve measurement with 13 N-NH3 ·H2 O PET/ CT imaging in pa-tients with coronary microvascular disease / 中华核医学与分子影像杂志

Objective To evaluate the diagnostic value of coronary flow reserve (CFR) on 13 N-NH3 ·H2 O PET/ CT imaging for patients with suspected coronary microvascular disease (CMVD). Meth-ods From September 2017 to September 2018, 54 clinical suspected CMVD patients (22 males, 32 fe-males; age: 25-77 years) in TEDA International Cardiovascular Hospital were retrospectively analyzed. All patients underwent 13N-NH3·H2O PET/ CT imaging to measure left ventricle CFR (LV-CFR), and were divided into CMVD group (LV-CFR<2.5) and non-CMVD group (LV-CFR≥2.5). Semi-quantitative parameters of PET/ CT myocardial perfusion imaging (MPI), including summed stress score (SSS), summed rest score (SRS), summed difference score (SDS) and transient ischemic dilation (TID), as well as left ventricular function parameters, such as rest and stress imaging left ventricular ejection fraction (LVEF), end-diastolic volume (EDV), and end-systolic volume (ESV) were compared between two groups. Besides, rest and stress LV-myocardial blood flow (MBF) and CFR distribution of the CMVD group in the region of three coro-nary arteries was also analyzed and compared. Independent-sample t test, Mann-Whitney U test and Pearson cor-relation analysis were used to analyze the data. Results Rest LV-MBF of CMVD group was higher than that of non-CMVD group ((0.74±0.16) vs (0. 63±0.09) ml·g-1 ·min-1 ) and stress LV-MBF was lower ((1.52± 0. 36) vs (1.89±0.22) ml·g-1 ·min-1; t values: 2.925, -4.503, both P<0.05). There was no signifi-cant difference between the two groups in other semi-quantitative parameters ( t values: from - 1. 430 to 1. 400, U values: 286.0-338.5, all P>0.05). Positive correlations were found in CFR among left anterior descending (LAD), left circumflex (LCX) and right coronary artery (RCA) (r values: 0.798-0.836, all P<0.01). Conclusion CFR measured with PET/ CT imaging is better than semi-quantitative parameters in MPI, which provides noninvasive and objective diagnosis and evaluation information for patients without ob-vious epicardial coronary artery stenosis and suspected with CMVD.

Incremental value of coronary flow reserve assessed by CZT-SPECT in the diagnosis of coronary artery disease / 中华核医学与分子影像杂志

Objective@#To investigate the incremental value of coronary flow reserve (CFR) assessed by cadmium zinc telluride(CZT)-SPECT as an adjunct to myocardial perfusion imaging (MPI) in the diagnosis of coronary artery disease (CAD).@*Methods@#Data of 132 patients (89 males, 43 females; 40-81 years) with or suspected with CAD who successfully underwent rest and stress MPI and CFR from November 2017 to October 2018 in Zhongshan Hospital Affiliated to Fudan University were retrospectively analyzed. Based on coronary angiography (CAG) as the " gold standard" , the value of MPI and MPI+ CFR in the diagnosis of CAD was evaluated and compared. χ2 test or Fisher exact probability test was used for data analysis.@*Results@#Of 132 patients, 61 (46.2%) were CAD with stenosis of at least 75% in one vessel (47.5%, 29/61), two vessels (34.4%, 21/61), or three vessels (18.0%, 11/61). A total of 104 (26.3%) vessels with stenosis of at least 75%, 25 (6.3%) vessels with stenosis of 65%-74%, and 30 (7.6%) vessels with stenosis of 50%-64% were found in 396 vessels. For detecting coronary stenosis of at least 75%, the sensitivity and accuracy of MPI on per-patient analysis were 86.89%(53/61) and 68.94%(91/132), which increased to 96.72%(59/61; χ2=3.921, P<0.05) and 87.88%(116/132; χ2=13.984, P<0.01) by MPI+ CFR. On per-vessel analysis, the sensitivity and accuracy of MPI were 72.12%(75/104) and 77.53%(307/396) and increased to 96.15%(100/104; χ2=22.511, P<0.01) and 85.10%(337/396; χ2=7.479, P<0.05) by MPI+ CFR. The sensitivity of MPI for predicting one, two, and three vessels disease were 72.41%(21/29), 42.86%(9/21), and 5/11 and were improved to 93.10%(27/29; χ2=4.350, P=0.037), 90.48%(19/21; χ2=10.714, P=0.001), and 11/11 (P=0.012) by MPI+ CFR. For coronary with stenosis of 65%-74%, the sensitivity of MPI was 24.00%(6/25) and was improved to 64.00%(16/25; χ2=8.117, P=0.004) by MPI+ CFR. For coronary with stenosis of 50%-64%, the sensitivity of MPI was 40.00%(12/30) and was improved to 76.67%(23/30; χ2=8.297, P=0.004) by MPI+ CFR.@*Conclusion@#As an adjunct to MPI, CFR can significantly improve the sensitivity and accuracy in the diagnosis of CAD, particularly for patients with mild stenosis and multivessel CAD.

Diagnostic value of blood flow reserve measurement with 13N-NH3·H2O PET/CT imaging in patients with coronary microvascular disease / 中华核医学与分子影像杂志

Objective@#To evaluate the diagnostic value of coronary flow reserve (CFR) on 13N-NH3·H2O PET/CT imaging for patients with suspected coronary microvascular disease (CMVD).@*Methods@#From September 2017 to September 2018, 54 clinical suspected CMVD patients (22 males, 32 females; age: 25-77 years) in TEDA International Cardiovascular Hospital were retrospectively analyzed. All patients underwent 13N-NH3·H2O PET/CT imaging to measure left ventricle CFR (LV-CFR), and were divided into CMVD group (LV-CFR<2.5) and non-CMVD group (LV-CFR≥2.5). Semi-quantitative parameters of PET/CT myocardial perfusion imaging (MPI), including summed stress score (SSS), summed rest score (SRS), summed difference score (SDS) and transient ischemic dilation (TID), as well as left ventricular function parameters, such as rest and stress imaging left ventricular ejection fraction (LVEF), end-diastolic volume (EDV), and end-systolic volume (ESV) were compared between two groups. Besides, rest and stress LV-myocardial blood flow (MBF) and CFR distribution of the CMVD group in the region of three coronary arteries was also analyzed and compared. Independent-sample t test, Mann-Whitney U test and Pearson correlation analysis were used to analyze the data.@*Results@#Rest LV-MBF of CMVD group was higher than that of non-CMVD group ((0.74±0.16) vs (0.63±0.09) ml·g-1·min-1) and stress LV-MBF was lower ((1.52±0.36) vs (1.89±0.22) ml·g-1·min-1; t values: 2.925, -4.503, both P<0.05). There was no significant difference between the two groups in other semi-quantitative parameters (t values: from -1.430 to 1.400, U values: 286.0-338.5, all P>0.05). Positive correlations were found in CFR among left anterior descending (LAD), left circumflex (LCX) and right coronary artery (RCA) (r values: 0.798-0.836, all P<0.01).@*Conclusion@#CFR measured with PET/CT imaging is better than semi-quantitative parameters in MPI, which provides noninvasive and objective diagnosis and evaluation information for patients without obvious epicardial coronary artery stenosis and suspected with CMVD.

The Current Status of Intervention for Intermediate Coronary Stenosis in the Korean Percutaneous Coronary Intervention (K-PCI) Registry

BACKGROUND AND OBJECTIVES: Intermediate coronary lesion that can be under- or over-estimated by visual estimation frequently results in stenting of functionally nonsignificant lesions or deferral of percutaneous coronary intervention (PCI) of significant lesions inappropriately. We evaluated current status of PCI for intermediate lesions from a standardized database in Korea. METHODS: We analyzed the Korean percutaneous coronary intervention (K-PCI) registry data which collected a standardized PCI database of the participating hospitals throughout the country from January 1, 2014, through December 31, 2014. Intermediate lesion was defined as a luminal narrowing between 50% and 70% by visual estimation and then compared whether the invasive physiologic or imaging study was performed or not. RESULTS: Physiology-guided PCI for intermediate lesions was performed in 16.8% for left anterior descending artery (LAD), 9.8% for left circumflex artery (LCX), 13.2% for right coronary artery (RCA). PCI was more frequently performed using intravascular ultrasound (IVUS) than using fractional flow reserve (FFR) for coronary artery segments (27.7% vs. 13.9% for LAD, 32.9% vs. 8.1% for LCX, and 33.8% vs. 10.8% for RCA). In accordance with or without FFR, PCI for intermediate lesions was more frequently performed in the hospitals with available FFR device than without FFR, especially in left main artery (LM), proximal LAD lesion (40.9% vs. 5.9% for LM, 24.6% vs 7.6% for proximal LAD). CONCLUSIONS: These data provide the current PCI practice pattern with the use of FFR and IVUS in intermediate lesion. More common use of FFR for intermediate lesion should be encouraged.