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5.
Eur Heart J ; 40(28): 2350-2359, 2019 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-31327012

RESUMO

AIMS: Continuous thermodilution is a novel technique to quantify absolute coronary flow and microvascular resistance (MVR). Notably, intracoronary infusion of saline elicits maximal hyperaemia, obviating the need for adenosine. The primary aim of this study was to validate continuous thermodilution in humans by comparing invasive measurements to [15O]H2O positron emission tomography (PET). As a secondary goal, absolute flow and MVR were compared between invasive measurements obtained with and without adenosine. METHODS AND RESULTS: Twenty-five patients underwent coronary computed tomography angiography (CCTA), [15O]H2O PET, and invasive assessment. Absolute coronary flow and MVR were measured in the left anterior descending and left circumflex artery using a dedicated infusion catheter and a temperature/pressure sensor-tipped guidewire. Invasive measurements were performed with and without adenosine. In order to compare invasive flow measurements with PET perfusion, subtending myocardial mass of the investigated vessels was derived from CCTA using the Voronoi algorithm. Invasive and non-invasive measurements of adenosine-induced hyperaemic flow and MVR showed strong correlation (r = 0.91; P < 0.001 for flow and r = 0.85; P < 0.001 for MVR) and good agreement [intraclass correlation coefficient (ICC) = 0.90; P < 0.001 for flow and ICC = 0.79; P < 0.001 for MVR]. Absolute flow and MVR also correlated well between measurements with and without adenosine (r = 0.97; P < 0.001 for flow and r = 0.98; P < 0.001 for MVR) and showed good agreement (ICC = 0.96; P < 0.001 for flow and ICC = 0.98; P < 0.001 for MVR). CONCLUSIONS: Continuous thermodilution is an accurate method to measure absolute coronary flow and MVR, which is evidenced by strong agreement with [15O]H2O PET derived flow and resistance. Absolute flow and MVR correlate highly between invasive measurements obtained with and without adenosine, which confirms that intracoronary infusion of room temperature saline elicits steady-state maximal hyperaemia.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31020797

RESUMO

OBJECTIVES: This study aimed to prospectively investigate intra-aortic balloon pump counterpulsation (IABP) support in large myocardial infarction complicated by persistent ischemia after primary percutaneous coronary intervention (PCI). BACKGROUND: Use of IABP is suggested to be effective by increasing diastolic aortic pressure, thereby improving coronary blood flow. This can only be expected with exhausted coronary autoregulation, typical in acute myocardial infarction complicated by persistent ischemia. In this situation, augmented diastolic pressure is expected to increase myocardial oxygenation. METHODS: One hundred patients with large STEMI complicated by persistent ischemia after primary PCI were randomized to treatment with or without IABP therapy on top of standard care. IABP support was initiated following primary PCI, immediately after inclusion. Primary end point was all-cause mortality, need for (additional) mechanical hemodynamic support, or readmission for heart failure within 6 months. RESULTS: Mean age was 63 ± 10 years, 76% were male. Mean systolic and diastolic blood pressure were 120 ± 25 mmHg and 73 ± 17 mmHg. Mean heart rate was 75 ± 18 mmHg. Before PCI, mean summed ST-deviation was 21 ± 8 mm with only minimal ST-resolution after PCI. One patient in the IABP group reached the primary end point versus four patients in the control group (2% vs. 8%; p = 0.16). After primary PCI, resolution of ST-deviation was significantly more pronounced in the IABP group (73 ± 17%) compared to the control group (56 ± 26%; p < 0.01). CONCLUSIONS: In this pilot study, in patients with large STEMI and persistent ischemia after primary PCI, use of IABP showed a nonsignificant decrease in mortality, necessity for (additional) mechanical hemodynamic support or readmission for heart failure at 6 months, and resulted in more rapid ST-resolution.

8.
Med Eng Phys ; 68: 65-75, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31006623

RESUMO

Hypothermia, if provided before coronary reperfusion, reduces infarct size in animal models of acute myocardial infarction (AMI). Translation to humans has failed so far, because the target temperature is not reached in time within the endangered myocardium using systemic hypothermia method. Hence, a clinically applicable method has been developed to provide intracoronary hypothermia using cold saline, selectively infused locally into the infarct area. In this study, a lumped parameter model has been designed to support the clinical method and to describe this myocardial cooling process mathematically. This model is able to predict the myocardial temperature changes over time, which cannot be measured, based on the temperature and flow of the intracoronary injected cold saline and coronary arterial blood. It was validated using data from an isolated beating porcine heart model and applied on data from patients with AMI undergoing intracoronary hypothermia. In prospect, the computational model may be used as an assistive tool to calculate the patient specific flow rate and temperature of saline required for reliable achievement of the target myocardial temperature in the hypothermia enhanced clinical treatment of AMI.


Assuntos
Simulação por Computador , Vasos Coronários/metabolismo , Hipotermia Induzida , Infarto do Miocárdio/terapia , Miocárdio/metabolismo , Temperatura Ambiente , Doença Aguda , Animais , Humanos , Modelos Cardiovasculares , Infarto do Miocárdio/metabolismo , Solução Salina/metabolismo , Suínos
9.
JAMA Cardiol ; 4(4): 370-374, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30840026

RESUMO

Importance: Whether the improvement in myocardial perfusion provided by percutaneous coronary intervention (PCI) is associated with symptomatic relief or improved outcomes has not been well investigated. Objective: To investigate the prognostic value of the improvement in fractional flow reserve (FFR) after PCI (ΔFFR) on patients' symptoms and 2-year outcomes. Design, Setting, and Participants: This study is a post hoc analysis of data from patients undergoing FFR-guided PCI in the randomized clinical trials Fractional Flow Reserve vs Angiography for Multivessel Evaluation (FAME) 1 (NCT00267774; 2009) and FAME 2 (NCT01132495; 2012), with inclusion of 2 years of follow-up data. The FAME 1 trial included patients with multivessel coronary artery disease from 20 medical centers in Europe and the United States. The FAME 2 trial included patients with stable coronary artery disease involving up to 3 vessels from 28 sites in Europe and North America. Lesions from the group in the FAME 1 trial from whom FFR was measured and the group in the FAME 2 trial who received FFR-guided PCI plus medical therapy were analyzed. Data analysis occurred from May 2017 to May 2018. Interventions: Measure of post-PCI FFR. Main Outcomes and Measures: Vessel-oriented clinical events at 2 years, a composite of cardiac death, target vessel-associated myocardial infarction, and target vessel revascularization. Results: This analysis included 639 patients from whom pre-PCI and post-PCI FFR values were available. Of their 837 lesions, 277 were classified into the lowest tertile (ΔFFR≤0.18), 282 into the middle tertile (0.19≤ΔFFR≤0.31), and 278 into the highest tertile (ΔFFR>0.31). Vessel-oriented clinical events were significantly more frequent in the lowest tertile (n = 25 of 277 [9.1%]) compared with the highest tertile (n = 13 of 278 [4.7%]; hazard ratio, 2.01 [95% CI, 1.03-3.92]; P = .04). In addition, a significant association was observed between ΔFFR and symptomatic relief (odds ratio, 1.33 [95% CI, 1.02-1.74]; P = .02). Conclusions and Relevance: In this analysis of 2 randomized clinical trials, the larger the improvement in FFR, the larger the symptomatic relief and the lower the event rate. This suggests that measuring FFR before and after PCI provides clinically useful information.

10.
Catheter Cardiovasc Interv ; 94(3): 356-363, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30702186

RESUMO

OBJECTIVES: To identify clinical, angiographic and hemodynamic predictors of discordance between instantaneous wave-free ratio (iFR) and fractional flow reserve (FFR). BACKGROUND: The iFR was found to be non-inferior to the gold-standard FFR for guiding coronary revascularization, although it is discordant with FFR in 20% of cases. A better understanding of the causes of discordance may enhance application of these indices. METHODS: Both FFR and iFR were measured in the prospective multicenter CONTRAST study. Clinical, angiographic and hemodynamic variables were compared between patients with concordant values of FFR and iFR (cutoff ≤0.80 and ≤0.89, respectively). RESULTS: Out of the 587 patients included, in 466 patients (79.4%) FFR and iFR agreed: both negative, n = 244 (41.6%), or positive, n = 222 (37.8%). Compared with FFR, iFR was negative discordant (FFR+/iFR-) in 69 (11.8%) patients and positive discordant (FFR-/iFR+) in 52 (8.9%) patients. On multivariate regression, stenosis location (left main or proximal left anterior descending) (OR: 3.30[1.68;6.47]), more severe stenosis (OR: 1.77[1.35;2.30]), younger age (OR: 0.93[0.90;0.97]), and slower heart rate (OR: 0.59[0.42;0.75]) were predictors of a negative discordant iFR. Absence of a beta-blocker (OR: 0.41[0.22;0.78]), older age (OR: 1.04[1.00;1.07]), and less severe stenosis (OR: 0.69[0.53;0.89]) were predictors of a positive discordant iFR. CONCLUSIONS: During iFR acquisition, stenosis location, stenosis degree, heart rate, age and use of beta blockers influence concordance with FFR and should be taken into account when interpreting iFR.

11.
Catheter Cardiovasc Interv ; 94(2): E61-E66, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30723996

RESUMO

OBJECTIVES: The objective was to evaluate the safety, feasibility, and accuracy of the jailed-pressure wire technique using a durable optical fiber-based pressure wire with high-pressure dilatation using a non-compliant balloon after main vessel stenting. BACKGROUND: Fractional flow reserve (FFR) information can help interventionists determine whether they should treat a jailed-side branch (SB). However, re-crossing a pressure wire into a jailed-SB is sometimes technically difficult. METHODS: Fifty-one consecutive lesions from 48 patients who underwent the jailed-pressure wire technique were retrospectively investigated. The primary endpoint was complication rate and secondary endpoints included success rate of FFR measurement, incidence of wire disruption, and final drift rate. The usability of FFR for percutaneous coronary intervention of coronary bifurcation lesion was also evaluated. RESULTS: Median age of the patients was 69 years and 80.4% were men. The most frequent underlying disease was stable angina (70.6%) and 68.6% were type B2 lesions. Our main findings were: the procedure was performed successfully in all cases without any complications or wire disruption, FFR could be measured without significant final drift in 95.9% of cases, and FFR measurements helped interventionists determine whether to perform a final kissing balloon dilatation in 49.0% cases. CONCLUSIONS: The jailed-pressure wire technique using a durable optical fiber-based pressure wire with high-pressure post-dilatation maneuver was safe, feasible, and accurate.

12.
Eur Heart J ; 40(2): 180-186, 2019 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-30596995

RESUMO

Aims: To assess the effect of fractional flow reserve (FFR)-guided percutaneous coronary intervention (PCI) with contemporary drug-eluting stents on the composite of cardiac death or myocardial infarction (MI) vs. medical therapy in patients with stable coronary lesions. Methods and results: We performed a systematic review and meta-analysis of individual patient data (IPD) of the three available randomized trials of contemporary FFR-guided PCI vs. medical therapy for patients with stable coronary lesions: FAME 2 (NCT01132495), DANAMI-3-PRIMULTI (NCT01960933), and Compare-Acute (NCT01399736). FAME 2 enrolled patients with stable coronary artery disease (CAD), while the other two focused on non-culprit lesions in stabilized patients after acute coronary syndrome. A total of 2400 subjects were recruited from 54 sites world-wide with 1056 randomly assigned to FFR-guided PCI and 1344 to medical therapy. The pre-specified primary outcome was a composite of cardiac death or MI. We included data from extended follow-ups for FAME 2 (up to 5.5 years follow-up) and DANAMI-3-PRIMULTI (up to 4.7 years follow-up). After a median follow-up of 35 months (interquartile range 12-60 months), a reduction in the composite of cardiac death or MI was observed with FFR-guided PCI as compared with medical therapy (hazard ratio 0.72, 95% confidence interval 0.54-0.96; P = 0.02). The difference between groups was driven by MI. Conclusion: In this IPD meta-analysis of the three available randomized controlled trials to date, FFR-guided PCI resulted in a reduction of the composite of cardiac death or MI compared with medical therapy, which was driven by a decreased risk of MI.

13.
EuroIntervention ; 14(15): e1601-e1608, 2019 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-29581085

RESUMO

AIMS: The aim of this study was to evaluate the predictability of resting distal coronary pressure wave forms for fractional flow reserve (FFR). METHODS AND RESULTS: Resting coronary wave forms were qualitatively evaluated for the presence of (i) dicrotic notch, (ii) diastolic dipping, and (iii) ventricularisation. In a development cohort (n=88), a scoring system was developed that was then applied to a validation cohort (n=428) using a multivariable linear regression model to predict FFR and receiver operating characteristics (ROC) to predict FFR ≤0.8. In the development cohort, all three qualitative parameters were independent predictors of FFR. However, in a multivariable linear regression model in the validation cohort, qualitative wave form analysis did not further improve the ability of resting distal coronary to aortic pressure ratio (Pd/Pa) (p=0.80) or instantaneous wave-free ratio (iFR) (p=0.26) to predict FFR. Using ROC, the area under the curve of resting Pd/Pa (0.86 versus 0.86, p=0.08) and iFR (0.86 versus 0.86, p=0.26) did not improve by adding qualitative analysis. CONCLUSIONS: Qualitative coronary wave form analysis showed moderate classification agreement in predicting FFR but did not add substantially to the resting pressure gradients Pd/Pa and iFR; however, when discrepancies between quantitative and qualitative analyses are observed, artefact or pressure drift should be considered.


Assuntos
Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Pressão Arterial , Vasos Coronários , Humanos , Pressão , Índice de Gravidade de Doença
14.
Circulation ; 138(17): 1797-1804, 2018 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-30354650

RESUMO

BACKGROUND: Whether the benefit in quality of life (QOL) after percutaneous coronary intervention depends on the severity of the stenosis as determined by fractional flow reserve (FFR) remains unknown. This study sought to investigate the relationship between FFR values and improvement in QOL. METHODS: From the FAME 1 and 2 trials (Fractional Flow Reserve Versus Angiography for Multivessel Evaluation), we identified 706 stable patients with coronary artery disease who had at least 1 lesion with an FFR≤0.80 that was treated with percutaneous coronary intervention and 185 patients with coronary artery disease who had no lesion with an FFR≤0.80 and were treated medically who served as a reference group. QOL was assessed by the European Quality of Life-5 Dimensions index at baseline, 1 month, and 1 year. We assessed the relationship between QOL improvement (defined as the change in European Quality of Life-5 Dimensions index from baseline) and FFR as a continuous value and according to abnormal FFR tertile. RESULTS: QOL improved significantly after percutaneous coronary intervention in each abnormal FFR tertile, whereas it did not change in the reference group. The lowest abnormal FFR subgroup had the greatest improvement in QOL at 1 month ( P<0.001). In mixed-effects models for repeated measures, lower FFR ( P=0.002 for 1 month and 0.049 for 1 year), greater delta FFR ( P=0.021 for 1 month and 0.025 for 1 year), and higher angina class ( P=0.001 for 1 month and <0.001 for 1 year) were associated with the greatest magnitude of QOL improvement at both 1 month and 1 year. CONCLUSIONS: Among patients with stable coronary artery disease, FFR and angina severity predict QOL improvement after percutaneous coronary intervention. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifiers: NCT00267774 and NCT01132495.


Assuntos
Angina Estável/terapia , Doença da Artéria Coronariana/terapia , Reserva Fracionada de Fluxo Miocárdico , Intervenção Coronária Percutânea , Qualidade de Vida , Idoso , Angina Estável/diagnóstico , Angina Estável/fisiopatologia , Cateterismo Cardíaco , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/fisiopatologia , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Recuperação de Função Fisiológica , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento
15.
J Am Coll Cardiol ; 72(12): 1321-1329, 2018 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-30213322

RESUMO

BACKGROUND: The residual SYNTAX (Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery) score (RSS) quantitatively assesses angiographic completeness of revascularization after percutaneous coronary intervention (PCI) and has been shown to be a predictor of events after angiography-guided PCI. In stable patients undergoing functionally complete revascularization with fractional flow reserve (FFR) guidance, RSS did not predict outcome. Whether this is also true in patients with acute coronary syndromes (ACS) is unknown. OBJECTIVES: The purpose of this study was to determine whether the RSS could predict outcomes in patients with ACS. METHODS: From the DANAMI-3-PRIMULTI (Primary PCI in Patients With ST-elevation Myocardial Infarction and Multivessel Disease: Treatment of Culprit Lesion Only or Complete Revascularization), FAME (Fractional Flow Reserve Versus Angiography for Multivessel Evaluation), and FAMOUS-NSTEMI (Fractional Flow Reserve Versus Angiographically Guided Management to Optimise Outcomes in Unstable Coronary Syndromes) trials, 547 patients presented with ACS and underwent functionally complete revascularization. Major adverse cardiac events (MACE) were defined as the composite endpoint of all-cause death, nonfatal myocardial infarction, and any repeat revascularization. The RSS was based on the recalculation of the SYNTAX score after PCI. We compared differences in 2-year outcome by the RSS subgroups: 0, 1 to <5, 5 to <10, ≥10 (RSS = 0 represents angiographically complete revascularization). RESULTS: The study population consisted of 271 patients with unstable angina/non-ST-segment elevation myocardial infarction and 276 with ST-segment elevation myocardial infarction. The mean RSS was 6.7 ± 5.8. MACE at 2 years occurred in 69 patients (12.6%). Patients with and without MACE had similar RSS after PCI (RSS: 7.2 ± 5.5 vs. 6.6 ± 5.9; p = 0.23). Kaplan-Meier curve analysis showed a similar incidence of MACE regardless of the RSS subgroups (p = 0.54). With and without adjustment of clinical variables, RSS was not a significant predictor of MACE or of each component of MACE. CONCLUSIONS: After complete revascularization of functionally significant stenosis by FFR, the extent of residual angiographic disease is not associated with subsequent ischemic events in patients presenting with ACS. These results suggest that the concept of functionally complete revascularization is applicable even in ACS patients. (Fractional Flow Reserve Versus Angiography for Multivessel Evaluation [F.A.M.E.] NCT00267774; Fractional Flow Reserve Versus Angiographically Guided Management to Optimise Outcomes in Unstable Coronary Syndromes [FAMOUS NSTEMI] NCT01764334; Primary PCI in Patients With ST-elevation Myocardial Infarction and Multivessel Disease: Treatment of Culprit Lesion Only or Complete Revascularization [DANAMI-3-PRIMULTI]; NCT01960933).


Assuntos
Síndrome Coronariana Aguda/terapia , Angiografia Coronária , Estenose Coronária/diagnóstico por imagem , Intervenção Coronária Percutânea , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Retratamento/estatística & dados numéricos
16.
JACC Cardiovasc Interv ; 11(15): 1454-1463, 2018 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-30031722

RESUMO

OBJECTIVES: The goal of this study was to investigate sex differences in adenosine-free coronary pressure indexes. BACKGROUND: Several adenosine-free coronary pressure wire indexes have been proposed to assess the functional significance of coronary artery lesions; however, there is a theoretical concern that sex differences may affect diagnostic performance because of differences in resting flow and distal myocardial mass. METHODS: In this CONTRAST (Can Contrast Injection Better Approximate FFR Compared to Pure Resting Physiology?) substudy, contrast fractional flow reserve (cFFR), obtained during contrast-induced submaximal hyperemia, the instantaneous wave-free ratio (iFR), and distal/proximal coronary pressure ratio (Pd/Pa) were compared with fractional flow reserve (FFR) in 547 men and 216 women. Using FFR ≤0.8 as a reference, the diagnostic performance of each index was compared. RESULTS: Men and women had similar diameter stenosis (p = 0.78), but women were less likely to have FFR ≤0.80 than men (42.5% vs. 51.5%, p = 0.04). Sensitivity was similar among cFFR, iFR, and Pd/Pa when comparing women and men, respectively (cFFR, 77.5% vs. 75.3%; p = 0.69; iFR, 84.9% vs. 79.4%; p = 0.30; Pd/Pa, 78.8% vs. 77.3%; p = 0.78). cFFR was more specific than iFR or Pd/Pa regardless of sex (cFFR, 94.3% vs. 95.8%; p = 0.56; iFR, 75.6% vs. 80.1%; p = 0.38; Pd/Pa, 80.6% vs. 78.7%; p = 0.69). By receiver-operating characteristic curve analysis, cFFR provided better diagnostic accuracy than resting indexes irrespective of sex (p ≤ 0.0001). CONCLUSIONS: Despite the theoretical concern, the diagnostic sensitivity and specificity of cFFR, iFR, and Pd/Pa did not differ between the sexes. Irrespective of sex, cFFR provides the best diagnostic performance.


Assuntos
Pressão Arterial , Cateterismo Cardíaco , Doença da Artéria Coronariana/diagnóstico , Estenose Coronária/diagnóstico , Reserva Fracionada de Fluxo Miocárdico , Adenosina/administração & dosagem , Idoso , Cateterismo Cardíaco/instrumentação , Cateteres Cardíacos , Meios de Contraste/administração & dosagem , Doença da Artéria Coronariana/fisiopatologia , Estenose Coronária/fisiopatologia , Feminino , Humanos , Hiperemia/fisiopatologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Fatores Sexuais , Transdutores de Pressão , Vasodilatadores/administração & dosagem
17.
Circ Cardiovasc Interv ; 11(3): e006194, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29870386

RESUMO

BACKGROUND: The principle of continuous thermodilution can be used to calculate absolute coronary blood flow and microvascular resistance (R). The aim of the study is to explore the safety, feasibility, and reproducibility of coronary blood flow and R measurements as measured by continuous thermodilution in humans. METHODS AND RESULTS: Absolute coronary flow and R can be calculated by thermodilution by infusing saline at room temperature through a dedicated monorail catheter. The temperature of saline as it enters the vessel, the temperature of blood and saline mixed in the distal part of the vessel, and the distal coronary pressure were measured by a pressure/temperature sensor-tipped guidewire. The feasibility and safety of the method were tested in 135 patients who were referred for coronary angiography. No significant adverse events were observed; in 11 (8.1%) patients, bradycardia and concomitant atrioventricular block appeared transiently and were reversed immediately on interruption of the infusion. The reproducibility of measurements was tested in a subgroup of 80 patients (129 arteries). Duplicate measurements had a strong correlation both for coronary blood flow (ρ=0.841, P<0.001; intraclass correlation coefficient=0.89, P<0.001) and R (ρ=0.780, P<0.001; intraclass correlation coefficient=0.89, P<0.001). In Bland-Altman plots, there was no significant bias or asymmetry. CONCLUSIONS: Absolute coronary blood flow (in L/min) and R (in mm Hg/L/min or Wood units) can be safely and reproducibly measured with continuous thermodilution. This approach constitutes a new opportunity for the study of the coronary microcirculation.


Assuntos
Síndrome Coronariana Aguda/diagnóstico , Angina Estável/diagnóstico , Cateterismo Cardíaco/instrumentação , Cateteres Cardíacos , Doença da Artéria Coronariana/diagnóstico , Circulação Coronária , Vasos Coronários/fisiopatologia , Microcirculação , Resistência Vascular , Síndrome Coronariana Aguda/diagnóstico por imagem , Síndrome Coronariana Aguda/fisiopatologia , Angina Estável/diagnóstico por imagem , Angina Estável/fisiopatologia , Velocidade do Fluxo Sanguíneo , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/fisiopatologia , Vasos Coronários/diagnóstico por imagem , Estudos de Viabilidade , Humanos , Valor Preditivo dos Testes , Encaminhamento e Consulta , Reprodutibilidade dos Testes , Termodiluição/instrumentação
18.
N Engl J Med ; 379(3): 250-259, 2018 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-29785878

RESUMO

BACKGROUND: We hypothesized that fractional flow reserve (FFR)-guided percutaneous coronary intervention (PCI) would be superior to medical therapy as initial treatment in patients with stable coronary artery disease. METHODS: Among 1220 patients with angiographically significant stenoses, those in whom at least one stenosis was hemodynamically significant (FFR, ≤0.80) were randomly assigned to FFR-guided PCI plus medical therapy or to medical therapy alone. Patients in whom all stenoses had an FFR of more than 0.80 received medical therapy and were entered into a registry. The primary end point was a composite of death, myocardial infarction, or urgent revascularization. RESULTS: A total of 888 patients underwent randomization (447 patients in the PCI group and 441 in the medical-therapy group). At 5 years, the rate of the primary end point was lower in the PCI group than in the medical-therapy group (13.9% vs. 27.0%; hazard ratio, 0.46; 95% confidence interval [CI], 0.34 to 0.63; P<0.001). The difference was driven by urgent revascularizations, which occurred in 6.3% of the patients in the PCI group as compared with 21.1% of those in the medical-therapy group (hazard ratio, 0.27; 95% CI, 0.18 to 0.41). There were no significant differences between the PCI group and the medical-therapy group in the rates of death (5.1% and 5.2%, respectively; hazard ratio, 0.98; 95% CI, 0.55 to 1.75) or myocardial infarction (8.1% and 12.0%; hazard ratio, 0.66; 95% CI, 0.43 to 1.00). There was no significant difference in the rate of the primary end point between the PCI group and the registry cohort (13.9% and 15.7%, respectively; hazard ratio, 0.88; 95% CI, 0.55 to 1.39). Relief from angina was more pronounced after PCI than after medical therapy. CONCLUSIONS: In patients with stable coronary artery disease, an initial FFR-guided PCI strategy was associated with a significantly lower rate of the primary composite end point of death, myocardial infarction, or urgent revascularization at 5 years than medical therapy alone. Patients without hemodynamically significant stenoses had a favorable long-term outcome with medical therapy alone. (Funded by St. Jude Medical and others; FAME 2 ClinicalTrials.gov number, NCT01132495 .).


Assuntos
Estenose Coronária/tratamento farmacológico , Estenose Coronária/terapia , Reserva Fracionada de Fluxo Miocárdico , Intervenção Coronária Percutânea , Idoso , Angina Pectoris/terapia , Anti-Hipertensivos/uso terapêutico , Doença das Coronárias/tratamento farmacológico , Doença das Coronárias/mortalidade , Doença das Coronárias/terapia , Estenose Coronária/fisiopatologia , Stents Farmacológicos , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/prevenção & controle , Inibidores da Agregação de Plaquetas/uso terapêutico , Retratamento/estatística & dados numéricos
19.
EuroIntervention ; 14(7): 806-814, 2018 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-29790478

RESUMO

AIMS: Randomised controlled trials have reported instantaneous wave-free ratio (iFR) to be non-inferior to fractional flow reserve (FFR) for major adverse cardiovascular events at one year; however, iFR is limited by sensitive landmarking of the pressure waveform, and the assumption that maximal flow and minimal resistance occur during a fixed period of diastole. We sought to validate the resting full-cycle ratio (RFR), a novel non-hyperaemic index of coronary stenosis severity based on unbiased identification of the lowest distal coronary pressure to aortic pressure ratio (Pd/Pa), independent of the ECG, landmark identification, and timing within the cardiac cycle. METHODS AND RESULTS: VALIDATE-RFR was a retrospective study designed to derive and validate the RFR. The primary endpoint was the agreement between RFR and iFR. RFR was retrospectively determined in 651 waveforms in which iFR was measured using a proprietary Philips/Volcano wire. RFR was highly correlated to iFR (R2=0.99, p<0.001), with a mean bias of -0.002 (95% limits of agreement -0.023 to 0.020). The diagnostic performance of RFR versus iFR was diagnostic accuracy 97.4%, sensitivity 98.2%, specificity 96.9%, positive predictive value 94.5%, negative predictive value 99.0%, area under the receiver operating characteristic curve of 0.996, and diagnostically equivalent within 1% (mean difference -0.002; 95% CI: -0.009 to 0.006, p=0.03). The RFR was detected outside diastole in 12.2% (341/2,790) of all cardiac cycles and 32.4% (167/516) of cardiac cycles in the right coronary artery where the sensitivity of iFR compared to FFR was lowest (40.6%). CONCLUSIONS: RFR is diagnostically equivalent to iFR but unbiased in its ability to detect the lowest Pd/Pa during the full cardiac cycle, potentially unmasking physiologically significant coronary stenoses that would be missed by assessment dedicated to specific segments of the cardiac cycle.


Assuntos
Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Vasos Coronários , Humanos , Estudos Retrospectivos , Índice de Gravidade de Doença
20.
Eur Heart J ; 39(28): 2646-2655, 2018 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-29617762

RESUMO

Aims: Echocardiography and tomographic imaging have documented dynamic changes in aortic stenosis (AS) geometry and severity during both the cardiac cycle and stress-induced increases in cardiac output. However, corresponding pressure gradient vs. flow relationships have not been described. Methods and results: We recruited 16 routine transcatheter aortic valve implantations (TAVI's) for graded dobutamine infusions both before and after implantation; 0.014″ pressure wires in the aorta and left ventricle (LV) continuously measured the transvalvular pressure gradient (ΔP) while a pulmonary artery catheter regularly assessed cardiac output by thermodilution. Before TAVI, ΔP did not display a consistent relationship with transvalvular flow (Q). Neither linear resistor (median R2 0.16) nor quadratic orifice (median R2 < 0.01) models at rest predicted stress observations; the severely stenotic valve behaved like a combination. The unitless ratio of aortic to left ventricular pressures during systolic ejection under stress conditions correlated best with post-TAVI flow improvement. After TAVI, a highly linear relationship (median R2 0.96) indicated a valid valve resistance. Conclusion: Pressure loss vs. flow curves offer a fundamental fluid dynamic synthesis for describing aortic valve pathophysiology. Severe AS does not consistently behave like an orifice (as suggested by Gorlin) or a resistor, whereas TAVI devices behave like a pure resistor. During peak dobutamine, the ratio of aortic to left ventricular pressures during systolic ejection provides a 'fractional flow reserve' of the aortic valve that closely approximates the complex, changing fluid dynamics. Because resting assessment cannot reliably predict stress haemodynamics, 'valvular fractional flow' warrants study to explain exertional symptoms in patients with only moderate AS at rest.

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