RESUMO
BACKGROUND AND AIMS: Wall shear stress (WSS) has an important role in the natural history of coronary atherosclerosis. The aim of this study is to investigate the relationship between WSS and the lipid content of atherosclerotic plaques as assessed by near-infrared spectroscopy (NIRS). METHODS: We performed serial NIRS and intravascular ultrasound (IVUS) upon Doppler coronary flow guidewire of coronary plaques at baseline and after 12-18 months in 28 patients with <30% angiographic stenosis, who presented with coronary artery disease. Segmental WSS, plaque burden and NIRS-derived lipid rich plaque (LRP) were evaluated at both time-points in 482 consecutive 2-mm coronary segments. RESULTS: Segments with LRP at baseline (nâ¯=â¯106) had a higher average WSS (1.4⯱â¯0.6â¯N/m2), compared to those without LRP (nâ¯=â¯376) (1.2⯱â¯0.6â¯N/m2, p<0.001). In segments without baseline LRP, WSS was higher in those who subsequently developed new LRP (nâ¯=â¯35) than those who did not (nâ¯=â¯341) (1.4⯱â¯0.8 vs. 1.1⯱â¯0.6â¯N/m2, p=0.002). Conversely, in segments with baseline LRP, WSS was lower in those who had regression of lipid content (nâ¯=â¯41) than those who did not (nâ¯=â¯65) (1.2⯱â¯0.4 vs. 1.6⯱â¯0.7â¯N/m2, p=0.007). Segments with the highest tertile of WSS displayed greater progression of LCBI irrespective of baseline lipid content (p<0.001). Multivariate analysis revealed that baseline WSS (p=0.017), PAV (p<0.001) and LCBI (p<0.001) were all independent predictors of change in LCBI over time. CONCLUSIONS: Coronary segments with high WSS associate with progression of lipid content over time, which may indicate transformation to a more vulnerable phenotype.
Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Estenose Coronária/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Metabolismo dos Lipídeos , Placa Aterosclerótica , Espectroscopia de Luz Próxima ao Infravermelho , Idoso , Velocidade do Fluxo Sanguíneo , Doença da Artéria Coronariana/metabolismo , Doença da Artéria Coronariana/patologia , Doença da Artéria Coronariana/terapia , Circulação Coronária , Estenose Coronária/metabolismo , Estenose Coronária/patologia , Estenose Coronária/terapia , Vasos Coronários/metabolismo , Vasos Coronários/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea , Prognóstico , Ruptura Espontânea , Índice de Gravidade de Doença , Estresse Mecânico , Fatores de Tempo , Ultrassonografia de IntervençãoRESUMO
OBJECTIVE: Coronary vasodilator function and atherosclerotic plaque progression have both been shown to be associated with adverse cardiovascular events. However, the relationship between these factors and the lipid burden of coronary plaque remains unknown. These experiments focus on investigating the relationship between impaired coronary vasodilator function (endothelium dependent (salbutamol) and endothelium independent (glyceryl trinitrate)) and the natural history of atheroma plaque progression and lipid burden using dual modality intravascular ultrasound (IVUS) and near-infrared spectroscopy (NIRS) imaging. METHODS: 33 patients with stable chest pain or acute coronary syndrome underwent serial assessment of coronary vasodilator function and intracoronary plaque IVUS and NIRS imaging. Coronary segmental macrovascular response (% change segmental lumen volume (ΔSLV)), plaque burden (per cent atheroma volume (PAV)), lipid core (lipid-rich plaque (LRP) and lipid core burden index (LCBI)) were measured at baseline and after an interval of 12-18 months (n=520 segments). RESULTS: Lipid-negative coronary segments which develop into LRP over the study time period demonstrated impaired endothelial-dependent function (-0.24±2.96 vs 5.60±1.47%, P=0.04) and endothelial-independent function (13.91±4.45 vs 21.19±3.19%, P=0.036), at baseline. By multivariate analysis, endothelial-dependent function predicted ∆LCBI (ß coefficient: -3.03, 95% CI (-5.81 to -0.25), P=0.033) whereas endothelial-independent function predicted ∆PAV (ß coefficient: 0.07, 95% CI (0.04 to 0.10), P<0.0001). CONCLUSIONS: Epicardial coronary vasodilator function is a determinant of future atheroma progression and composition irrespective of the nature of clinical presentation. TRIAL REGISTRATION NUMBER: ACTRN12612000594820, Post-results.
Assuntos
Albuterol/farmacologia , Doença da Artéria Coronariana , Vasos Coronários , Endotélio Vascular , Nitroglicerina/farmacologia , Placa Aterosclerótica , Vasodilatação , Idoso , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/patologia , Doença da Artéria Coronariana/fisiopatologia , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/patologia , Vasos Coronários/fisiopatologia , Progressão da Doença , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Lipídeos/análise , Masculino , Pessoa de Meia-Idade , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/metabolismo , Valor Preditivo dos Testes , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Ultrassonografia de Intervenção/métodos , Vasodilatação/efeitos dos fármacos , Vasodilatação/fisiologia , Vasodilatadores/farmacologiaAssuntos
Hipertensão Pulmonar/diagnóstico , Artéria Pulmonar/fisiopatologia , Circulação Pulmonar , Tomografia Computadorizada por Raios X/métodos , Resistência Vascular/fisiologia , Cateterismo Cardíaco , Feminino , Humanos , Hipertensão Pulmonar/fisiopatologia , Masculino , Pessoa de Meia-Idade , Artéria Pulmonar/diagnóstico por imagemRESUMO
BACKGROUND: No unified method exists to effectively predict and monitor progression of pulmonary arterial hypertension (PAH). We assessed the longitudinal relationship between a novel marker of cardiopulmonary reserve and established prognostic surrogate markers in patients with pulmonary vascular disease. METHODS AND RESULTS: Twenty participants with confirmed (n = 14) or at high risk (n = 6) for PAH underwent cardiovascular magnetic resonance (CMR) at baseline and after ~6 months of guideline-appropriate management. Ten PAH participants underwent RHC within 48 h of each CMR. RHC (mean pulmonary arterial pressure, mPAP; pulmonary vascular resistance index, PVRI; cardiac index, CI) and phase-contrast CMR (mean pulmonary arterial blood flow velocity, meanPAvel) measurements were taken at rest and during continuous adenosine infusion (70/140/210 mcg/kg/min). Initial meanPAvel's (rest and hyperemic) were correlated with validated surrogate prognostic parameters (CMR: RV ejection fraction, RVEF; RV end systolic volume indexed, RVESVI; RHC: PVRI, CI; biomarker: NT-pro brain natriuretic peptide, NTpBNP; clinical: 6-min walk distance, 6MWD), a measure of pulmonary arterial stiffness (elastic modulus) and volumetric estimation of RV ventriculoarterial (VA) coupling. Changes in meanPAvel's were correlated with changes in comparator parameters over time. At initial assessment, meanPAvel at rest correlated significantly with PVRI (inversely), CI (positively) and elastic modulus (inversely) (R 2 > 0.37,P < 0.05 for all), whereas meanPAvel at peak hyperemia correlated significantly with PVRI, RVEF, RVESVI, 6MWD, elastic modulus and VA coupling (R 2 > 0.30,P < 0.05 for all). Neither resting or hyperemia-derived meanPAvel correlated with NTpBNP levels. Initial meanPAvel at rest correlated significantly with RVEF, RVESVI, CI and VA coupling at follow up assessment (R 2 > 0.2,P < 0.05 for all) and initial meanPAvel at peak hyperemia correlated with RVEF, RVESVI, PVRI and VA coupling (R 2 > 0.37,P < 0.05 for all). Change in meanPAvel at rest over time did not show statistically significant correlation with change in prognostic parameters, while change in meanPAvel at peak hyperemia did show a significant relationship with ΔRVEF, ΔRVESVI, ΔNTpBNP and ΔCI (R 2 > 0.24,P < 0.05 for all). CONCLUSION: MeanPAvel during peak hyperemia correlated with invasive, non-invasive and clinical prognostic parameters at different time points. Further studies with predefined clinical endpoints are required to evaluated if this novel tool is a marker of disease progression in patients with pulmonary vascular disease.
Assuntos
Aptidão Cardiorrespiratória , Hemodinâmica , Hipertensão Pulmonar/diagnóstico por imagem , Imageamento por Ressonância Magnética , Artéria Pulmonar/diagnóstico por imagem , Adenosina/administração & dosagem , Adulto , Idoso , Pressão Arterial , Biomarcadores/sangue , Progressão da Doença , Módulo de Elasticidade , Feminino , Humanos , Hiperemia/fisiopatologia , Hipertensão Pulmonar/fisiopatologia , Hipertensão Pulmonar/terapia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Projetos Piloto , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Artéria Pulmonar/fisiopatologia , Volume Sistólico , Fatores de Tempo , Resistência Vascular , Rigidez Vascular , Vasodilatadores/administração & dosagem , Função Ventricular Direita , Teste de CaminhadaRESUMO
Aortic distensibility (AD) decreases with age and increased aortic stiffness is independently associated with adverse cardiovascular outcomes. The association of severe aortic stenosis (AS) with AD in different aortic regions has not been evaluated. Elderly subjects with severe AS and a cohort of patients without AS of similar age were studied. Proximal aortic cross-sectional-area changes during the cardiac cycle were determined using retrospective-ECG-gating on 128-detector row computed-tomography. Using oscillometric-brachial-blood-pressure measurements, the AD at the ascending-aorta (AA), proximal-descending-aorta (PDA) and distal-descending-aorta (DDA) was determined. Linear mixed effects modelling was used to determine the association of age and aortic stenosis on regional AD. 102 patients were evaluated: 36 AS patients (70-85 years), 24 AS patients (>85 years) and 42 patients without AS (9 patients <50 years, 20 patients between 51-70 years and 13 patients 70-85 years). When comparing patients 70-85 years, AA distensibility was significantly lower in those with AS compared to those without AS (0.9 ± 0.9 vs. 1.4 ± 1.1, P = 0.03) while there was no difference in the PDA (1.0 ± 1.1 vs. 1.0 ± 1.2, P = 0.26) and DDA (1.1 ± 1.2 vs. 1.2 ± 0.8, P = 0.97). In patients without AS, AD decreased with age in all aortic regions (P < 0.001). The AA in patients <50 years were the most distensible compared to other aortic regions. There is regional variation in aortic distensibility with aging. Patients with aortic stenosis demonstrated regional differences in aortic distensibility with lower distensibility demonstrated in the proximal ascending aorta compared to an age-matched cohort.
Assuntos
Fatores Etários , Envelhecimento , Aorta Torácica/diagnóstico por imagem , Doenças da Aorta/diagnóstico por imagem , Estenose da Valva Aórtica/diagnóstico por imagem , Aortografia/métodos , Tomografia Computadorizada Multidetectores , Rigidez Vascular , Idoso , Idoso de 80 Anos ou mais , Aorta Torácica/fisiopatologia , Doenças da Aorta/fisiopatologia , Estenose da Valva Aórtica/fisiopatologia , Arteriopatias Oclusivas/diagnóstico por imagem , Arteriopatias Oclusivas/fisiopatologia , Técnicas de Imagem de Sincronização Cardíaca , Constrição Patológica , Eletrocardiografia , Feminino , Hemodinâmica , Humanos , Modelos Lineares , Masculino , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/fisiopatologiaRESUMO
Myocarditis and acute coronary syndrome are both described in the setting of concurrent hypersensitivity reactions to a variety of allergenic triggers (hypersensitivity myocarditis and Kounis syndrome respectively). Mast cell degranulation is thought to be pivotal in the pathogenesis of both clinical entities. Cardiac magnetic resonance imaging (CMR) has assumed a key role in the assessment of chest pain syndromes, providing a useful non-invasive tool to aid clinical decision-making. Despite increasing availability and uptake of CMR, only a small fraction of published Kounis syndrome cases report CMR findings, and confirmation of myocardial infarction remains elusive. We present a case of presumed Kounis syndrome with comprehensive CMR imaging that provides an insight into why these two well-described clinical entities share many clinical features - perhaps they are one and the same.