RESUMEN
Dedicated coronary artery drug-eluting stents may be inadequate in coronary arteries >6 mm in diameter, due to the risk of stent undersizing if the stent is not fully expanded or to loss of radial strength or damage to the drug coating if the stent is expanded >6 mm. We present two patients with large coronary arteries who were successfully treated with biliary balloon expandable stents.
RESUMEN
Computed tomography (CTA)-derived fractional flow reserve (FFRCT) guides the need for invasive coronary angiography (ICA). Late outcomes after FFRCT are reported in stable ischemic heart disease but not in acute chest pain in the emergency department (ACP-ED). The objectives are to assess the risk of death, myocardial infarction (MI), revascularization, and ICA after FFRCT. From 2015 to 2018, 389 low-risk patients with ACP-ED (negative biomarkers, no electrocardiographic ischemia) underwent CTA and FFRCT and were entered into a prospective institutional registry; patients were followed up for 41 ± 10 months. CTA stenosis ≥50% was present in 81% of the patients. Positive (FFRCT ≤0.80) and negative FFRCT were observed in 124 (32%) and 265 patients (68%), respectively. ICA was performed in 108 of 124 patients (87%) with positive FFRCT and 89 of 265 patients (34%) with negative FFRCT (p <0.00001). Revascularization was performed in 87 of 124 (70%) patients with positive FFRCT and in 22 of 265 (8%) with negative FFRCT (p <0.00001). Appropriateness of revascularization was established by blinded adjudication of ICA and invasive FFR using practice guidelines; revascularization was appropriate in 81 of 124 (65%) and 6 of 265 (2%) of FFRCT-positive and -negative patients, respectively (p <0.00001). At follow-up, for patients with positive versus negative FFRCT, the rates were 0.8% versus 0% for death (p = 0.32) and 1.6% versus 0.4% for MI (p = 0.24). In conclusion, in low-risk patients with ACP-ED who underwent CTA and FFRCT, the risk of late death (0.2%) and MI (0.7%) are low. Negative FFRCT is associated with excellent long-term prognosis, and positive FFRCT predicts obstructive disease requiring revascularization. FFRCT can safely triage patients with ACP-ED and reduce unnecessary ICA and revascularization.
Asunto(s)
Dolor en el Pecho , Angiografía Coronaria , Servicio de Urgencia en Hospital , Reserva del Flujo Fraccional Miocárdico , Humanos , Reserva del Flujo Fraccional Miocárdico/fisiología , Masculino , Femenino , Persona de Mediana Edad , Anciano , Dolor en el Pecho/fisiopatología , Dolor en el Pecho/etiología , Revascularización Miocárdica , Estudios Prospectivos , Infarto del Miocardio/fisiopatología , Infarto del Miocardio/complicaciones , Angiografía por Tomografía Computarizada , Estenosis Coronaria/fisiopatología , Estenosis Coronaria/diagnóstico por imagen , Estenosis Coronaria/complicaciones , Tomografía Computarizada por Rayos X/métodos , Sistema de Registros , Pronóstico , Estudios de SeguimientoRESUMEN
Hyperemic and nonhyperemic pressure ratios are frequently used to assess the hemodynamic significance of coronary artery disease and to guide the need for myocardial revascularization. However, there are limited data on the diagnostic performance of the diastolic hyperemia-free ratio (DFR). We evaluated the diagnostic performance of the DFR compared with invasive fractional flow reserve (FFR). We performed a prospective, single-center study of 308 patients (343 lesions) who underwent DFR and FFR for evaluation of visually estimated 40% to 90% stenoses. Diagnostic performance of the DFR compared with FFR was evaluated using linear regression, Bland-Altman analysis, and receiver operating characteristic curves. The overall diagnostic accuracy of the DFR was 83%; the accuracy rates were 86%, 40%, and 95% when the DFR was <0.86, 0.88 to 0.90, and >0.93, respectively. The sensitivity, specificity, positive predicative value, and negative predictive value were 60%, 91%, 71%, and 87%, respectively. The Pearson correlation coefficient was 0.75 (p <0.05). The Bland-Altman analysis showed a mean difference of 0.09, and the area under the receiver operating characteristic curve was 0.88 (95% confidence interval 0.84 to 0.92, p <0.05). In conclusion, the DFR has a good diagnostic performance compared with FFR but 17% of the measurements were discordant. The diagnostic accuracy of the DFR was only 40% when the DFR was 0.88 to 0.90, suggesting that FFR may be useful in these arteries.
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Enfermedad de la Arteria Coronaria , Estenosis Coronaria , Reserva del Flujo Fraccional Miocárdico , Humanos , Enfermedad de la Arteria Coronaria/diagnóstico , Estenosis Coronaria/diagnóstico , Estudios Prospectivos , Vasos Coronarios/diagnóstico por imagen , Reproducibilidad de los Resultados , Valor Predictivo de las Pruebas , Angiografía Coronaria , Índice de Severidad de la EnfermedadRESUMEN
Coronary computed tomography angiography (CCTA) and CCTA-derived fractional flow reserve (FFRCT) are the best non-invasive techniques to assess coronary artery disease (CAD) and myocardial ischemia. Advances in these technologies allow a paradigm shift to the use of CCTA and FFRCT for advanced plaque characterization and planning myocardial revascularization.
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Enfermedad de la Arteria Coronaria , Reserva del Flujo Fraccional Miocárdico , Humanos , Reserva del Flujo Fraccional Miocárdico/fisiología , Angiografía Coronaria/métodos , Angiografía por Tomografía Computarizada/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/cirugía , Revascularización MiocárdicaRESUMEN
We report a patient with severe mitral annular calcification, mitral stenosis/regurgitation, hypertrophic obstructive cardiomyopathy, and subaortic membrane treated with valved left atrium-left ventricle conduit, septal myectomy, and membrane resection. Subsequent thrombosis of the conduit prompted successful valve-in- mitral annular calcification transcatheter mitral valve replacement and laceration of the anterior mitral leaflet to prevent outflow obstruction. (Level of Difficulty: Advanced.).
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Renal artery stenosis is the most common secondary cause of hypertension and predominantly caused by atherosclerosis. In suspected patients, a non-invasive diagnosis with ultrasound is preferred. Asymptomatic, incidentally found RAS does not require revascularization. In symptomatic patients requiring revascularization, renal artery stenting is the preferred therapy. Selecting appropriate patients for revascularization requires careful consideration of lesion severity and is optimized with a multidisciplinary team. All patients with atherosclerotic RAS should be treated with guideline-directed medical therapy, including hypertension control, diabetes control, statins, antiplatelet therapy, smoking cessation and encouraging activity.
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Procedimientos Endovasculares , Obstrucción de la Arteria Renal/terapia , Arteria Renal/cirugía , Injerto Vascular , Fármacos Cardiovasculares/uso terapéutico , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/instrumentación , Ejercicio Físico , Humanos , Prevalencia , Arteria Renal/diagnóstico por imagen , Arteria Renal/fisiopatología , Obstrucción de la Arteria Renal/diagnóstico por imagen , Obstrucción de la Arteria Renal/epidemiología , Obstrucción de la Arteria Renal/fisiopatología , Medición de Riesgo , Factores de Riesgo , Conducta de Reducción del Riesgo , Cese del Hábito de Fumar , Stents , Resultado del TratamientoRESUMEN
BACKGROUND: Values of fractional flow reserve (FFRCT) by coronary computed tomography angiography (CTA) decline from the ostium to the terminal vessel, irrespective of stenosis severity. The purpose of this study is to determine if the site of measurement of FFRCT impacts assessment of ischemia and its diagnostic performance relative to invasive FFR (FFRINV). METHODS: 1484 patients underwent FFRCT; 1910 vessels were stratified by stenosis severity (normal; <25%, 25-50%, 50-70%, and >70% stenosis). The rates of positive FFRCT (≤0.8) were determined by measuring FFRCT from the terminal vessel and from distal-to-the-lesion. Reclassification rates from positive to negative FFRCT were calculated. Diagnostic performance of FFRCT relative to FFRINV was evaluated in 182 vessels using linear regression, Bland Altman analysis, and receiver operating characteristic (ROC) curves. RESULTS: Positive FFRCT was identified in 24.9% of vessels using terminal vessel FFRCT and 10.1% using FFRCT distal-to-the-lesion (p â< â0.001). FFRCT obtained distal-to-the-lesion resulted in reclassification of 59.6% of positive terminal FFRCT to negative FFRCT. Relative to FFRINV, there were improvements in specificity (50% to 86%, p â< â0.001), diagnostic accuracy (65% to 88%, p â< â0.001), positive predictive value (50% to 78%, p â< â0.001), and area-under-the-curve (AUC, 0.83 to 0.91, p â< â0.001) when FFRCT was measured distal-to-the-lesion. CONCLUSION: FFRCT values from the terminal vessel should not be used to assess lesion-specific ischemia due to high rates of false positive results. FFRCT measured distal-to-the-lesion improves the diagnostic performance of FFRCT relative to FFRINV, ensures that FFRCT values are due to lesion-specific ischemia, and could reduce the rate of unnecessary invasive procedures.
Asunto(s)
Angiografía por Tomografía Computarizada , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Estenosis Coronaria/diagnóstico por imagen , Reserva del Flujo Fraccional Miocárdico , Anciano , Enfermedad de la Arteria Coronaria/fisiopatología , Estenosis Coronaria/fisiopatología , Bases de Datos Factuales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Interpretación de Imagen Radiográfica Asistida por Computador , Índice de Severidad de la EnfermedadRESUMEN
Coronavirus disease 2019 is a global pandemic affecting >3 million people in >170 countries, resulting in >200 000 deaths; 35% to 40% of patients and deaths are in the United States. The coronavirus disease 2019 crisis is placing an enormous burden on health care in the United States, including residency and fellowship training programs. The balance between mitigation, training and education, and patient care is the ultimate determinant of the role of cardiology fellows in training during the coronavirus disease 2019 crisis. On March 24, 2020, the Accreditation Council for Graduate Medical Education issued a formal response to the pandemic crisis and described a framework for operation of graduate medical education programs. Guidance for deployment of cardiology fellows in training during the coronavirus disease 2019 crisis is based on the principles of a medical mission, and adherence to preparation, protection, and support of our fellows in training. The purpose of this review is to describe our departmental strategic deployment of cardiology fellows in training using the Accreditation Council for Graduate Medical Education framework for pandemic preparedness.
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Cardiólogos/organización & administración , Certificación/organización & administración , Infecciones por Coronavirus/terapia , Atención a la Salud/organización & administración , Educación de Postgrado en Medicina , Necesidades y Demandas de Servicios de Salud/organización & administración , Fuerza Laboral en Salud/organización & administración , Admisión y Programación de Personal/organización & administración , Neumonía Viral/terapia , Betacoronavirus/patogenicidad , COVID-19 , Cardiólogos/economía , Competencia Clínica , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/virología , Humanos , Pandemias , Neumonía Viral/diagnóstico , Neumonía Viral/epidemiología , Neumonía Viral/virología , Desarrollo de Programa , Evaluación de Programas y Proyectos de Salud , SARS-CoV-2 , Especialización , Carga de TrabajoRESUMEN
Invasive pressure measurements using hyperemic fractional flow reserve (FFR) and nonhyperemic pressure measurements (NHPR) are superior to angiography alone for assessment of 50-90% stenoses. FFR devices using piezoelectric and optical sensors achieve 94% concordance in FFR values; microcatheter designs have more lesion-crossing failures and less pressure drift compared with guidewire designs. Despite the similarity in statistical performance among FFR devices, interventional cardiologists may prefer to use NHPR to avoid the need for adenosine-related side effects, variations in vasodilator response, and limited application in patients with certain clinical and anatomic features.
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Estenosis Coronaria , Reserva del Flujo Fraccional Miocárdico , Angiografía Coronaria , Reserva del Flujo Fraccional Miocárdico/efectos de los fármacos , Cabeza , Humanos , Índice de Severidad de la Enfermedad , Tecnología , Resultado del Tratamiento , VasodilatadoresRESUMEN
OBJECTIVES: This study sought to examine the feasibility, safety, clinical outcomes, and costs associated with computed tomography-derived fractional flow reserve (FFRCT) in acute chest pain (ACP) patients in a coronary computed tomography angiography (CTA)-based triage program. BACKGROUND: FFRCT is useful in determining lesion-specific ischemia in patients with stable ischemic heart disease, but its utility in ACP has not been studied. METHODS: ACP patients with no known coronary artery disease undergoing coronary CTA and coronary CTA with FFRCT were studied. FFRCT ≤0.80 was considered positive for hemodynamically significant stenosis. RESULTS: Among 555 patients, 297 underwent coronary CTA and FFRCT (196 negative, 101 positive), whereas 258 had coronary CTA only. The rejection rate for FFRCT was 1.6%. At 90 days, there was no difference in major adverse cardiac events (including death, nonfatal myocardial infarction, and unexpected revascularization after the index visit) between the coronary CTA and FFRCT groups (4.3% vs. 2.7%; p = 0.310). Diagnostic failure, defined as discordance between the coronary CTA or FFRCT results with invasive findings, did not differ between the groups (1.9% vs. 1.68%; p = NS). No deaths or myocardial infarction occurred with negative FFRCT when revascularization was deferred. Negative FFRCT was associated with higher nonobstructive disease on invasive coronary angiography (56.5%) than positive FFRCT (8.0%) and coronary CTA (22.9%) (p < 0.001). There was no difference in overall costs between the coronary CTA and FFRCT groups ($8,582 vs. $8,048; p = 0.550). CONCLUSIONS: In ACP, FFRCT is feasible, with no difference in major adverse cardiac events and costs compared with coronary CTA alone. Deferral of revascularization is safe with negative FFRCT, which is associated with higher nonobstructive disease on invasive angiography.
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Angina de Pecho/diagnóstico por imagen , Servicio de Cardiología en Hospital , Angiografía por Tomografía Computarizada , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Estenosis Coronaria/diagnóstico por imagen , Servicio de Urgencia en Hospital , Reserva del Flujo Fraccional Miocárdico , Anciano , Angina de Pecho/economía , Angina de Pecho/fisiopatología , Angina de Pecho/terapia , Servicio de Cardiología en Hospital/economía , Angiografía por Tomografía Computarizada/economía , Angiografía Coronaria/economía , Enfermedad de la Arteria Coronaria/economía , Enfermedad de la Arteria Coronaria/fisiopatología , Enfermedad de la Arteria Coronaria/terapia , Estenosis Coronaria/economía , Estenosis Coronaria/fisiopatología , Estenosis Coronaria/terapia , Servicio de Urgencia en Hospital/economía , Estudios de Factibilidad , Femenino , Costos de Hospital , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Sistema de Registros , Reproducibilidad de los Resultados , Estudios Retrospectivos , TriajeRESUMEN
BACKGROUND/PURPOSE: General Anesthesia (GA) and conscious sedation (CS) are anesthetics for transfemoral transcatheter aortic valve replacement (TF-TAVR). We compared TF-TAVR outcomes using a novel anesthetic approach with fascia iliaca block (FIB) plus minimal CS (MCS) versus GA. METHODS: This retrospective propensity-matched study included consecutive TF-TAVR patients from January 2013 to December 2017 and dichotomized into FIB-MCS vs. GA. Data were collected from electronic records, Society of Thoracic Surgery (STS) database, and the Transcatheter Valve Therapies (TVT) Registry. Primary endpoints were operating room (OR) time, intensive care unit (ICU) and hospital length of stay (LOS). Secondary endpoints were 30-day, 1-year mortality, quality of life, 30-day re-hospitalization rate, failure of FIB-MCS, and hospital safety outcomes. RESULTS: A total of 304 TF-TAVR patients; FIB-MCS (nâ¯=â¯219) vs. GA (nâ¯=â¯85). Propensity matched 162 patients; FIB-MCS (nâ¯=â¯108) vs. GA (nâ¯=â¯54). FIB-MCS had shorter OR time (197.6⯱â¯56.3 vs. 248.2⯱â¯46.3â¯min, pâ¯<â¯0.001), ICU (67.8⯱â¯71.7 vs. 84.9⯱â¯72.1â¯h, pâ¯=â¯0.004) and hospital LOS (3.2⯱â¯3.7 vs. 5.9⯱â¯3.5 d, pâ¯<â¯0.001). FIB-MCS had lower rate of blood transfusion. FIB-MCA vs. GA 30-day and 1-year mortality were similar in the entire (2.3 vs. 2.4%, pâ¯=â¯1.0; and 8.2 vs. 5.9%, pâ¯=â¯0.49) and matched cohorts (0 vs. 3.7%, pâ¯=â¯0.11 and 7.4 vs. 5.6%, pâ¯=â¯0.75). FIB-MCS were less likely to be re-hospitalized [Odd Ratio: 0.32, CI:0.13-0.76] and 2% to 3% higher KCCQ-12 score. CONCLUSION: TF-TAVR using FIB-MCS is feasible and safe with shorter OR time, ICU and hospital LOS, lower risk of 30-day re-hospitalization, similar 30-day and 1-year mortality with better quality of life at 1-year follow-up.
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Anestesia General , Estenosis de la Válvula Aórtica/cirugía , Cateterismo Periférico , Sedación Consciente , Arteria Femoral , Bloqueo Nervioso , Reemplazo de la Válvula Aórtica Transcatéter , Anciano , Anciano de 80 o más Años , Anestesia General/efectos adversos , Anestesia General/mortalidad , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/mortalidad , Cateterismo Periférico/efectos adversos , Cateterismo Periférico/mortalidad , Sedación Consciente/efectos adversos , Sedación Consciente/mortalidad , Bases de Datos Factuales , Registros Electrónicos de Salud , Femenino , Humanos , Tiempo de Internación , Masculino , Bloqueo Nervioso/efectos adversos , Bloqueo Nervioso/mortalidad , Tempo Operativo , Readmisión del Paciente , Punciones , Calidad de Vida , Sistema de Registros , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Reemplazo de la Válvula Aórtica Transcatéter/mortalidad , Resultado del TratamientoRESUMEN
BACKGROUND: Invasive fractional flow reserve (FFRINV) is the standard technique for assessing myocardial ischemia. Pressure distortions and measurement location may influence FFRINV interpretation. We report a technique for performing invasive fractional flow reserve (FFRINV) by minimizing pressure distortions and identifying the proper location to measure FFRINV. METHODS: FFRINV recordings were obtained prospectively during manual hyperemic pullback in 100 normal and diseased coronary arteries with single stenosis, using 4 measurements from the terminal vessel, distal-to-the-lesion, proximal vessel, and guiding catheter. FFRINV profiles were developed by plotting FFRINV values (y-axis) and site of measurement (x-axis), stratified by stenosis severity. FFRINV≤0.8 was considered positive for lesion-specific ischemia. RESULTS: Erroneous FFRINV values were observed in 10% of vessels because of aortic pressure distortion and in 21% because of distal pressure drift; these were corrected by disengagement of the guiding catheter and re-equalization of distal pressure/aortic pressure, respectively. There were significant declines in FFRINV from the proximal to the terminal vessel in normal and stenotic coronary arteries (P<0.001). The rate of positive FFRINV was 41% when measured from the terminal vessel and 20% when measured distal-to-the-lesion (P<0.001); 41.5% of positive terminal measurements were reclassified to negative when measured distal-to-the-lesion. Measuring FFRINV 20 to 30 mm distal-to-the-lesion (rather than from the terminal vessel) can reduce errors in measurement and optimize the assessment of lesion-specific ischemia. CONCLUSIONS: Meticulous technique (disengagement of the guiding catheter, FFRINV pullback) is required to avoid erroneous FFRINV, which occur in 31% of vessels. Even with optimal technique, FFRINV values are influenced by stenosis severity and the site of pressure measurement. FFRINV values from the terminal vessel may overestimate lesion-specific ischemia, leading to unnecessary revascularization.
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Cateterismo Cardíaco/métodos , Enfermedad de la Arteria Coronaria/diagnóstico , Estenosis Coronaria/diagnóstico , Vasos Coronarios/fisiopatología , Reserva del Flujo Fraccional Miocárdico , Anciano , Estudios de Casos y Controles , Toma de Decisiones Clínicas , Enfermedad de la Arteria Coronaria/fisiopatología , Enfermedad de la Arteria Coronaria/terapia , Estenosis Coronaria/fisiopatología , Estenosis Coronaria/terapia , Femenino , Humanos , Hiperemia/fisiopatología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad , Vasodilatadores/administración & dosificaciónAsunto(s)
Estenosis de la Válvula Aórtica/cirugía , Válvula Aórtica/cirugía , Cateterismo Cardíaco , Ecocardiografía Doppler , Hemodinámica , Reemplazo de la Válvula Aórtica Transcatéter , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/fisiopatología , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/fisiopatología , Humanos , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Reemplazo de la Válvula Aórtica Transcatéter/efectos adversos , Resultado del TratamientoRESUMEN
Fractional flow reserve derived by coronary computed tomography angiography (CTA; FFRCT) is an accurate noninvasive method for identifying coronary artery disease (CAD) and detecting hemodynamically significant stenosis. Although initially proposed as noninvasive tools to "rule out" significant CAD in low-risk patients, CTA and FFRCT are now utilized in higher-risk patients. Furthermore, new applications of CTA and FFRCT include a planning tool for percutaneous coronary intervention (PCI), which allows the cardiologist to assess lesion-specific ischemia, plan stent locations and sizes, and use virtual remodeling of the lumen (virtual stenting) to assess the functional impact of PCI. The purpose of this review is to discuss the principles of CTA and FFRCT acquisition, and their application for PCI planning, even before invasive angiography is performed.
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Angiografía por Tomografía Computarizada , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Estenosis Coronaria/terapia , Vasos Coronarios/diagnóstico por imagen , Reserva del Flujo Fraccional Miocárdico , Hemodinámica , Toma de Decisiones Clínicas , Enfermedad de la Arteria Coronaria/fisiopatología , Enfermedad de la Arteria Coronaria/terapia , Estenosis Coronaria/diagnóstico por imagen , Estenosis Coronaria/fisiopatología , Vasos Coronarios/fisiopatología , Humanos , Intervención Coronaria Percutánea , Valor Predictivo de las Pruebas , Índice de Severidad de la EnfermedadRESUMEN
Noninvasive fractional flow reserve derived from coronary CT angiography (FFRCT) is increasingly used in patients with coronary artery disease as a gatekeeper to the catheterization laboratory. While there is emerging evidence of the clinical benefit of FFRCT in patients with moderate coronary disease as determined with coronary CT angiography, there has been less focus on interpretation, reporting, and integration of FFRCT results into routine clinical practice. Because FFRCT analysis provides a plethora of information regarding pressure and flow across the entire coronary tree, standardized criteria on interpretation and reporting of the FFRCT analysis result are of crucial importance both in context of the clinical adoption and in future research. This report represents expert opinion and recommendation on a standardized FFRCT interpretation and reporting approach. Published under a CC BY 4.0 license.
RESUMEN
BACKGROUND: Fractional flow reserve (FFR)-derived from computed tomography angiography (CTA; FFRCT) and invasive FFR (FFRINV) are used to assess the need for invasive coronary angiography (ICA) and percutaneous coronary intervention (PCI). The optimal location for measuring FFR and the impact of measurement location have not been well defined. METHODS: 930 patients (age 60.7 + 10 years, 59% male) were included in this study. Normal and diseased coronary arteries were classified into stenosis grades 0-4 in the left anterior descending artery (LAD, n = 518), left circumflex (LCX, n = 112) and right coronary artery (RCA, n = 585). FFRCT (n = 1215 arteries) and FFRINV (n = 26 LAD) profiles were developed by plotting FFR values (y-axis) versus site of measurement (x-axis: ostium, proximal, mid, distal segments). The best location to measure FFR was defined relative to the distal end of the stenosis. FFR ≤0.8 was considered positive for ischemia. RESULTS: In normal and stenotic coronary arteries there are significant declines in FFRCT and FFRINV from the ostium to the distal vessel (pâ¯<â¯0.001), due to lesion-specific ischemia and to effects unrelated to the lesion. A reliable location (distal to the stenosis) is 10.5â¯mm [IQR 7.3-14.8â¯mm] for FFRCT and within 20-30â¯mm for FFRINV. Rates of positive FFR (from the distal vessel) reclassified to negative FFR (distal to the stenosis) are 61% (FFRCT) and 33% (FFRINV). CONCLUSION: FFRCT and FFRINV values are influenced by stenosis severity and the site of measurement. FFR measurements from the distal vessel may over-estimate lesion-specific ischemia and result in unnecessary referrals for ICA and PCI.