RESUMO
Cardiac amyloidosis is an infiltrative disease which requires a high degree of clinical suspicion for appropriate diagnosis. Early diagnosis and the definition of the type of amyloidosis play a key role in the early treatment and prognosis of this disease. In this context, the use of cardiac biomarkers such as troponins and NT-proBNT associated with analysis by multimodality imaging methods like echocardiographic techniques such as strain, nuclear medicine, and cardiovascular resonance imaging have an increasing role in patients with cardiac amyloidosis. This article details the role of non-invasive diagnostic methods in patients with cardiac amyloidosis.
Assuntos
Amiloidose/diagnóstico , Biomarcadores , Ecocardiografia , Humanos , Espectroscopia de Ressonância Magnética , Prognóstico , Cintilografia , Tomografia Computadorizada por Raios XRESUMO
SUMMARY Cardiac amyloidosis is an infiltrative disease which requires a high degree of clinical suspicion for appropriate diagnosis. Early diagnosis and the definition of the type of amyloidosis play a key role in the early treatment and prognosis of this disease. In this context, the use of cardiac biomarkers such as troponins and NT-proBNT associated with analysis by multimodality imaging methods like echocardiographic techniques such as strain, nuclear medicine, and cardiovascular resonance imaging have an increasing role in patients with cardiac amyloidosis. This article details the role of non-invasive diagnostic methods in patients with cardiac amyloidosis.
RESUMO A amiloidose cardíaca é uma doença infiltrativa que exige um alto grau de suspeição clínica para o diagnóstico apropriado. O diagnóstico precoce e a definição do subtipo de amiloidose têm um papel fundamental para a terapêutica e prognóstico desta doença. Nesse contexto, o emprego de biomarcadores cardíacos como as troponinas e NT-proBNT associados à análise por métodos de imagem multimodalidade por técnicas ecocardiográficas atuais como o strain, medicina nuclear e a ressonância magnética cardíaca têm papel crescente em pacientes com amiloidose. Este artigo detalha a utilização dos métodos não invasivos para a avaliação de pacientes com amiloidose cardíaca.
Assuntos
Humanos , Amiloidose/diagnóstico , Prognóstico , Ecocardiografia , Espectroscopia de Ressonância Magnética , Biomarcadores , Cintilografia , Tomografia Computadorizada por Raios XRESUMO
OBJECTIVES: Despite advances in non-invasive myocardial perfusion imaging (MPI) evaluation, computed tomography (CT) multiphase MPI protocols have not yet been compared with the highly accurate rubidium-82 positron emission tomography (82RbPET) MPI. Thus, this study aimed to evaluate agreement between 82RbPET and 320-detector row CT (320-CT) MPI using a multiphase protocol in suspected CAD patients. METHODS: Forty-four patients referred for MPI evaluation were prospectively enrolled and underwent dipyridamole stress 82RbPET and multiphase 320-CT MPI (five consecutive volumetric acquisitions during stress). Statistical analyses were performed using the R software. RESULTS: There was high agreement for recognizing summed stress scores ≥ 4 (kappa 0.77, 95% CI 0.55-0.98, p < 0.001) and moderate for detecting SDS ≥ 2 (kappa 0.51, 95% CI 0.23-0.80, p < 0.001). In a per segment analysis, agreement was high for the presence of perfusion defects during stress and rest (kappa 0.75 and 0.82, respectively) and was moderate for impairment severity (kappa 0.58 and 0.65, respectively). The 320-CT protocol was safe, with low radiation burden (9.3 ± 2.4 mSv). CONCLUSIONS: There was a significant agreement between dipyridamole stress 320-CT MPI and 82RbPET MPI in the evaluation of suspected CAD patients of intermediate risk. The multiphase 320-CT MPI protocol was feasible, diagnostic and with relatively low radiation exposure. KEY POINTS: ⢠Rubidium-82 PET and 320-MDCT can perform MPI studies for CAD investigation. ⢠There is high agreement between rubidium-82 PET and 320-MDCT for MPI assessment. ⢠Multiphase CT perfusion protocols are feasible and with low radiation. ⢠Multiphase CT perfusion protocols can identify image artefacts.
Assuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Compostos Radiofarmacêuticos , Radioisótopos de Rubídio , Angiografia por Tomografia Computadorizada , Vasos Coronários/diagnóstico por imagem , Dipiridamol/farmacologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores , Imagem de Perfusão do Miocárdio/métodos , Tomografia por Emissão de Pósitrons/métodos , Estudos Prospectivos , Software , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Vasodilatadores/farmacologiaRESUMO
AIMS: The pathophysiological mechanisms of left ventricular non-compaction cardiomyopathy (LVNC) remain controversial. This study performed combined 18F-fluoro-2-deoxyglucose dynamic positron emission tomography (FDG-PET) and 99mTc-sestamibi single-photon emission computed tomography (SPECT) studies to evaluate myocardial glucose metabolism and perfusion in patients with LVNC and their clinical implications. METHODS AND RESULTS: Thirty patients (41 ± 12 years, 53% male) with LVNC, diagnosed by cardiovascular magnetic resonance (CMR) criteria, and eight age-matched healthy controls (42 ± 12 years, 50% male) were prospectively recruited to undergo FDG-PET with measurement of the myocardial glucose uptake rate (MGU) and SPECT to investigate perfusion-metabolism patterns. Patients with LVNC had lower global MGU compared with that in controls (36.9 ± 8.8 vs. 44.6 ± 5.4 µmol/min/100 g, respectively, P = 0.02). Of 17 LV segments, MGU levels were significantly reduced in 8, and also a reduction was observed when compacted segments from LVNC were compared with the segments from control subjects (P < 0.001). Perfusion defects were also found in 15 (50%) patients (45 LV segments: 64.4% match, and 35.6% mismatch perfusion-metabolism pattern). Univariate and multivariate analyses showed that beta-blocker therapy was associated with increased MGU (beta coefficient = 10.1, P = 0.008). Moreover, a gradual increase occurred in MGU across the beta-blocker dose groups (P for trend = 0.01). CONCLUSION: The reduction of MGU documented by FDG-PET in LVNC supports the hypothesis that a cellular metabolic pathway may play a role in the pathophysiology of LVNC. The beneficial effect of beta-blocker mediating myocardial metabolism in the clinical course of LVNC requires further investigation.
Assuntos
Miocárdio Ventricular não Compactado Isolado/diagnóstico por imagem , Miocárdio Ventricular não Compactado Isolado/fisiopatologia , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Disfunção Ventricular Esquerda/diagnóstico por imagem , Adulto , Análise de Variância , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Fluordesoxiglucose F18 , Glucose/metabolismo , Humanos , Aumento da Imagem , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos , Índice de Gravidade de Doença , Volume Sistólico/fisiologia , Disfunção Ventricular Esquerda/fisiopatologiaAssuntos
Doença da Artéria Coronariana/diagnóstico por imagem , Imagem de Perfusão do Miocárdio/métodos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Compostos Radiofarmacêuticos , Rubídio , Tecnécio Tc 99m Sestamibi , Angiografia Coronária/métodos , Doença da Artéria Coronariana/fisiopatologia , Feminino , Reserva Fracionada de Fluxo Miocárdico , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos TestesAssuntos
Humanos , Feminino , Pessoa de Meia-Idade , Rubídio , Doença da Artéria Coronariana/diagnóstico por imagem , Tecnécio Tc 99m Sestamibi , Compostos Radiofarmacêuticos , Imagem de Perfusão do Miocárdio/métodos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Doença da Artéria Coronariana/fisiopatologia , Reprodutibilidade dos Testes , Angiografia Coronária/métodos , Reserva Fracionada de Fluxo MiocárdicoRESUMO
PURPOSE: Myocardial perfusion imaging (MPI) with 99mTc-sestamibi (sestamibi) SPECT and rubidium-82 (82Rb) PET both allow for combined assessment of perfusion and left ventricular (LV) function. We sought to compare parameters of LV function obtained with both methods using a single dipyridamole stress dose. MATERIALS AND METHODS: A group of 221 consecutive patients (65.2 ± 10.4 years, 52.9% male) underwent consecutive sestamibi and 82Rb MPI after a single dipyridamole stress dose. Sestamibi and 82Rb summed rest (SRS), stress (SSS) and difference (SDS) scores, and LV end-diastolic (EDV) and end-systolic (ESV) volumes and left ventricular ejection fraction (LVEF) were compared. RESULTS: Bland-Altman analysis showed that with increasing ESV and EDV the difference between the two perfusion tracers increased both at rest and post-stress. The mean difference in EDV and ESV between the two perfusion tracers at rest could both be independently explained by the 82Rb SDS and the sestamibi SRS. The combined models explained approximately 30% of the variation in these volumes between the two perfusion tracers (R2 = 0.261, p = 0.005; R2 = 0.296, p < 0.001, for EDV and ESV respectively). However, the mean difference in LVEF between sestamibi and 82Rb showed no significant trend post-stress (R2 = 0.001, p = 0.70) and only a modest linear increase with increasing LVEF values at rest (R2 = 0.032, p = 0.009). CONCLUSIONS: Differences in left ventricular volumes between sestamibi and 82Rb MPI increase with increasing volumes. However, these differences did only marginally affect LVEF between sestamibi and 82Rb. In clinical practice these results should be taken into account when comparing functional derived parameters between sestamibi and 82Rb MPI.
Assuntos
Tomografia Computadorizada por Emissão de Fóton Único de Sincronização Cardíaca , Dipiridamol/farmacologia , Imagem de Perfusão do Miocárdio , Tomografia por Emissão de Pósitrons , Radioisótopos de Rubídio , Tecnécio Tc 99m Sestamibi , Função Ventricular Esquerda/efeitos dos fármacos , Idoso , Eletrocardiografia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Estresse Fisiológico/efeitos dos fármacos , Função Ventricular Esquerda/fisiologiaRESUMO
OBJECTIVES: Perfusion abnormalities are frequently seen in Single Photon Emission Computed Tomography (SPECT) when a left bundle branch block is present. A few studies have shown decreased coronary flow reserve in the left anterior descending territory, regardless of the presence of coronary artery disease. OBJECTIVE: We sought to investigate rubidium-82 (82Rb) positron emission tomography imaging in the assessment of myocardial blood flow and coronary flow reserve in patients with left bundle branch block. METHODS: Thirty-eight patients with left bundle branch block (GI), median age 63.5 years, 22 (58%) female, 12 with coronary artery disease (≥70%; GI-A) and 26 with no evidence of significant coronary artery disease (GI-B), underwent rest-dipyridamole stress 82Rb-positron emission tomography with absolute quantitative flow measurements using Cedars-Sinai software (mL/min/g). The relative myocardial perfusion and left ventricular ejection fraction were assessed in 17 segments. These parameters were compared with those obtained from 30 patients with normal 82Rb-positron emission tomography studies and without left bundle branch block (GII). RESULTS: Stress myocardial blood flow and coronary flow reserve were significantly lower in GI than in GII (p<0.05). The comparison of coronary flow reserve between GI-A and GI-B showed that it was different from the global coronary flow reserve (p<0.05) and the stress flow was significantly lower in the anterior than in the septal wall for both groups. Perfusion abnormalities were more prevalent in GI-A (p=0.06) and the left ventricular ejection fraction was not different between GI-A and GI-B, whereas it was lower in GI than in GII (p<0.001). CONCLUSION: The data confirm that patients with left bundle branch block had decreased myocardial blood flow and coronary flow reserve and coronary flow reserve assessed by 82Rb-positron emission tomography imaging may be useful in identifying coronary artery disease in patients with left bundle branch block.
Assuntos
Bloqueio de Ramo/diagnóstico por imagem , Doença da Artéria Coronariana/diagnóstico por imagem , Circulação Coronária/fisiologia , Tomografia por Emissão de Pósitrons/métodos , Idoso , Bloqueio de Ramo/fisiopatologia , Doença da Artéria Coronariana/fisiopatologia , Feminino , Reserva Fracionada de Fluxo Miocárdico/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Imagem de Perfusão do Miocárdio/métodos , Radioisótopos de Rubídio , Volume Sistólico/fisiologiaRESUMO
OBJECTIVES: Perfusion abnormalities are frequently seen in Single Photon Emission Computed Tomography (SPECT) when a left bundle branch block is present. A few studies have shown decreased coronary flow reserve in the left anterior descending territory, regardless of the presence of coronary artery disease. OBJECTIVE: We sought to investigate rubidium-82 (82Rb) positron emission tomography imaging in the assessment of myocardial blood flow and coronary flow reserve in patients with left bundle branch block. METHODS: Thirty-eight patients with left bundle branch block (GI), median age 63.5 years, 22 (58%) female, 12 with coronary artery disease (≥70%; GI-A) and 26 with no evidence of significant coronary artery disease (GI-B), underwent rest-dipyridamole stress 82Rb-positron emission tomography with absolute quantitative flow measurements using Cedars-Sinai software (mL/min/g). The relative myocardial perfusion and left ventricular ejection fraction were assessed in 17 segments. These parameters were compared with those obtained from 30 patients with normal 82Rb-positron emission tomography studies and without left bundle branch block (GII). RESULTS: Stress myocardial blood flow and coronary flow reserve were significantly lower in GI than in GII (p<0.05). The comparison of coronary flow reserve between GI-A and GI-B showed that it was different from the global coronary flow reserve (p<0.05) and the stress flow was significantly lower in the anterior than in the septal wall for both groups. Perfusion abnormalities were more prevalent in GI-A (p=0.06) and the left ventricular ejection fraction was not different between GI-A and GI-B, whereas it was lower in GI than in GII (p<0.001). CONCLUSION: The data confirm that patients with left bundle branch block had decreased myocardial blood flow and coronary flow reserve and coronary flow reserve assessed by 82Rb-positron emission tomography imaging may be useful in identifying coronary artery disease in patients with left bundle branch block.