ABSTRACT
Abstract Background: Anthracycline generates progressive left ventricular dysfunction associated with a poor prognosis. Objectives: The purpose of this study was to evaluate whether layer-specific strain analysis could assess the subclinical left ventricular dysfunction after exposure to anthracycline. Methods: Forty-two anthracycline-treated survivors of large B-cell non-Hodgkin lymphoma, aged 55.83 ± 17.92 years (chemotherapy group) and 27 healthy volunteers, aged 51.39 ± 13.40 years (control group) were enrolled. The cumulative dose of epirubicin in chemotherapy group was 319.67 ± 71.71mg/m2. The time from last dose of epirubicin to the echocardiographic examination was 52.92 ± 22.32 months. Global longitudinal (GLS), circumferential (GCS) and radial strain (GRS), subendocardial, mid and subepicardial layer of longitudinal (LS-ENDO, LS-MID, LS-EPI) and circumferential strain (CS-ENDO, CS-MID, CS-EPI) values were analyzed. Transmural strain gradient was calculated as differences in peak systolic strain between the subendocardial and subepicardial layers. A value of p < 0.05 was considered significant. Results: Conventional parameters of systolic and diastolic function showed no significant difference between two groups. Compared with controls, patients had significantly lower GCS and GLS. Multi-layer speckle tracking analysis showed significant reduction of circumferential strain of subendocardial layer, transmural CS gradient and longitudinal strain of all three layers. In contrast, the two groups did not differ in transmural longitudinal strain gradient and radial strains. Conclusions: It proved the preferential impairment of subendocardial deformation in long-term survivors after exposure to anthracycline. Multi-layer speckle tracking echocardiography might facilitate the longitudinal follow-up of this at-risk patient cohort.
Resumo Fundamentos: A antraciclina gera uma disfunção ventricular esquerda progressiva associada a um prognóstico ruim. Objetivos: O propósito deste estudo foi avaliar se a análise layer específico de strain poderia avaliar disfunção ventricular esquerda subclínica após exposição a antraciclina. Métodos: Foram inscritos quarenta e dois sobreviventes tratados com antraciclina por linfoma não Hodgkin de células B grandes, de 55,83 ± 17,92 anos (grupo de quimioterapia) e 27 voluntários saudáveis, de 51,39 ± 13,40 anos (grupo controle). A dose cumulativa de epirrubicina no grupo de quimioterapia foi de 319,67 ± 71,71 mg/m2. O tempo desde a última dose de epirrubicina até o exame ecocardiográfico foi de 52,92 ± 22,32 meses. Analisaram-se o strain longitudinal global (GLS), o circunferencial (GCS) e o strain radial (GRS), os valores das camadas subendocárdica, média e subepicárdica so strain longitudinal (LS-ENDO, LS-MID, LS-EPI) e do strain circunferencial (CS-ENDO, CS-MID, CS-EPI). O gradiente de strain transmural foi calculado como a diferença no strain sistólico pico entre as camadas subendocárdicas e subepicárdicas. Um valor de p < 0,05 foi considerado significativo. Resultados: Os parâmetros convencionais da função sistólica e diastólica não mostraram diferenças significativas entre dois grupos. Comparados aos controles, os pacientes apresentaram GCS e GLS significativamente menores. A análise de speckle tracking multi-layer mostrou uma redução significativa no strain circunferencial da camada subendocárdica, o gradiente transmural CS e o strain longitudinal das três camadas. Em contraste, os dois grupos não diferiram no gradiente de strain longitudinal transmural e de strain radiais. Conclusões: Provou-se a deterioração preferencial do strain subendocárdico em sobreviventes de longa duração após exposição à antraciclina. O ecocardiograma de speckle tracking multi-layer pode facilitar o acompanhamento longitudinal dessa coorte de pacientes em risco. (Arq Bras Cardiol. 2018; 110(3):219-228)
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Young Adult , Echocardiography/methods , Lymphoma, B-Cell/drug therapy , Ventricular Dysfunction, Left/chemically induced , Ventricular Dysfunction, Left/diagnostic imaging , Anthracyclines/adverse effects , Antibiotics, Antineoplastic/adverse effects , Reference Values , Stroke Volume/drug effects , Stroke Volume/physiology , Epirubicin/therapeutic use , Case-Control Studies , Observer Variation , Cross-Sectional Studies , Risk Factors , Analysis of Variance , Follow-Up Studies , Ventricular Dysfunction, Left/physiopathology , Statistics, Nonparametric , Cardiotoxicity/etiology , Cardiotoxicity/diagnostic imaging , Heart/drug effects , Heart/physiopathology , Myocardium/pathologyABSTRACT
Abstract Backgrounds: Despite their clear therapeutic benefits, anthracycline-induced cardiotoxicity is a major concern limiting the ability to reduce morbidity and mortality associated with cancers. The early identification of anthracycline-induced cardiotoxicity is of vital importance to assess the cardiac risk against the potential cancer treatment. Objective: To investigate whether speckle-tracking analysis can provide a sensitive and accurate measurement when detecting doxorubicin-induced left ventricular injury. Methods: Wistar rats were divided into 4 groups with 8 rats each, given doxorubicin intraperitoneally at weekly intervals for up to 4 weeks. Group 1: 2.5 mg/kg/week; group 2: 3 mg/kg/week; group 3: 3.5mg/kg/week; group 4: 4mg/kg/week. An additional 5 rats were used as controls. Echocardiographic images were obtained at baseline and 1 week after the last dose of treatment. Radial (Srad) and circumferential (Scirc) strains, radial (SRrad) and circumferential (SRcirc) strain rates were analyzed. After the experiment, cardiac troponin I (cTnI) was analyzed and the heart samples were histologically evaluated. Results: After doxorubicin exposure, LVEF was significantly reduced in group 4 (p = 0.006), but remained stable in the other groups. However, after treatment, Srads were reduced in groups 2, 3 and 4 (p all < 0.05). The decrease in Srads was correlated with cTnI (rho = -0.736, p = 0.000) and cardiomyopathy scores (rho = -0.797, p = 0.000). Conclusion: Radial strain could provide a sensitive and noninvasive index in early detection of doxorubicin-induced myocardial injury. The changes in radial strain had a significant correlation with myocardial lesions and serum cardiac troponin I levels, indicating that this parameter could accurately evaluate cardiotoxicity severity.
Resumo Fundamento: Apesar dos seus claros benefícios terapêuticos, a cardiotoxicidade induzida pela antraciclina é uma grande preocupação que limita a capacidade de reduzir a morbidade e mortalidade associadas com cânceres. A identificação precoce da cardiotoxicidade induzida por antraciclina é de vital importância para o equilíbrio entre o risco cardíaco e o potencial tratamento do câncer. Objetivo: Investigar se a análise por speckle-tracking pode fornecer uma medida sensível e precisa na detecção de lesão ventricular esquerda induzida por doxorrubicina. Métodos: Ratos Wistar foram divididos em 4 grupos de 8 ratos cada, e doxorrubicina foi administrada intraperitonealmente em intervalos semanais de até 4 semanas. Grupo 1: 2,5 mg/kg/semana; Grupo 2: 3 mg/kg/semana; Grupo 3: 3,5 mg/kg/semana; Grupo 4: 4 mg/kg/semana. Foram utilizados 5 ratos adicionais como controles. As imagens ecocardiográficas foram obtidas na linha basal e 1 semana após a última dose do tratamento. Foram analisados o strain radial (Srad) e circunferencial (Scirc) e as taxas de strain radial (TSrad) e circunferencial (TScirc). Após o experimento, a troponina cardíaca I (cTnI) foi analisada e as amostras cardíacas foram avaliadas histologicamente. Resultados: Após a exposição à doxorrubicina, a FEVE foi significativamente reduzida no grupo 4 (p = 0,006), mas permaneceu estável nos outros grupos. Entretanto, após o tratamento, os Srads foram reduzidos nos grupos 2, 3 e 4 (p < 0,05). A diminuição dos Srads foi correlacionada com cTnI (rho = -0,736, p = 0,000) e os escores de cardiomiopatia (rho = -0,797, p = 0,000). Conclusão: O strain radial pode fornecer um índice sensível e não-invasivo na detecção precoce da lesão miocárdica induzida pela doxorrubicina. As alterações do strain radial apresentaram correlação significativa com lesões miocárdicas e níveis séricos de troponina I cardíaca, indicando que esse parâmetro pode avaliar com precisão a gravidade da cardiotoxicidade.
ABSTRACT
The effects of testosterone on norepinephrine release were investigated in the isolated rat hearts.Sprague-Dawley male rats (n=120) were randomized to testosterone and control groups.The rats in testosterone group were perfused with modified Krebs-Henseleit buffer containing different concentrations of testosterone (0.1,1.0,10.0,and 100.0 nmol/L,respectively).Myocardial ischemia was induced by globally stopping the perfusion flow.Exocytotic norepinephrine release was induced by electrical field stimulation at 5 V (effective voltage) and 6 Hz (pulse width of 2 ms) for 1 min.The overflow of norepinephrine was determined by high pressure liquid chromatography and electrochemical detection (HPLC-EC).Following acute ischemia,testosterone (1.0,10.0 and 100.0 nmol/L) significantly reduced norepinephrine release (P＜0.01),and the norepinepherine overflow was similar between the control and 0.1 nmol/L testosterone group (P＞0.05).Electrical stimulation of the ventricle evoked norepinepherine release,and this was diminished by the perfusion with testosterone at the concentrations of 1.0,10.0 and 100.0 nmol/L (P＜0.01).It is suggested that testosterone suppresses ischemia- and electrical stimulation-induced norepinepherine release in the isolated rat hearts.
ABSTRACT
Summary: The aim of this study was to determine if the potassium aspartate and magnesium (PAM) prevent reperfusion-induced ventricular arrhythmias (RIVA) in ischcmia-reperfusion (IR) rabbit heart. Thirty rabbits were randomly divided into control, ischemia and PAM groups. Arterially-perfused rabbit left ventricular preparations were made, and transmural ECG as well as action potentials from both endocardium and epicardium were simultaneously recorded in the whole process of all experiments. In control group rabbit ventricular wedge preparations were continuously perfused with Tyrode's solution, and in ischemia group and PAM groups the perfusion of Tyrode's solution was stopped for 30 min. Then the ischemia group was reperfused with Tyrode's solution and the PAM group with Tyrode's solution containing 2.42 mg/L PAM, respectively. ECG, QT interval, transmural repolarization dispersion (TDR) and action potentials from epicardium and endocardium were simultaneously recorded, and the RIVA of the wedge preparation was observed. Compared with control group, TDR and incidence of RIVA were significantly increased in ischemia group (P<0.05). The incidence of RIVA in control, ischemia and PAM group was 0/10, 9/10 and 1/10, respectively. Compared with ischemia group, TDR and incidence of RIVA were significantly reduced in PAM group (P<0.05). Potassium aspartate and magnesium significantly reduce TDR and prevent ventricular arrhythmia in ischemic rabbit heart.