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1.
Blood Purif ; 50(3): 347-354, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33105133

RESUMO

INTRODUCTION: Patients with CKD have an impaired health-related quality of life (QoL). Most studies have been conducted on dialysis patients, and less is known about QoL and its determinants in predialysis patients. We studied the association between QoL and comorbidities, cardiac biomarkers, echocardiography, and mortality in patients with CKD stage 4-5 not on dialysis. METHODS: A total of 140 patients enrolled in the Chronic Arterial Disease, Quality of Life and Mortality in Chronic Kidney Injury (CADKID) study filled the Kidney Disease Quality of Life Short Form (KDQOL-SF) at the beginning of the study. Echocardiography and biochemical parameters were obtained at baseline. Patients were followed up for at least 2 years or until death. RESULTS: The median age was 66 years, and 51 (36%) patients were female. The median estimated glomerular filtration rate was 13 mL/min per 1.73 m2. Obesity, diabetes, atrial fibrillation, and congestive heart failure were associated with lower QoL scores in multiple KDQOL-SF domains. Cardiac biomarkers, troponin T (p = 0.02), N-terminal pro-B-type natriuretic peptide (p = 0.006), and the echocardiographic parameter of cardiac systolic function left ventricular global longitudinal strain (p = 0.02) were significant predictors of lower physical component summary (PCS) score in multivariable regression models after controlling for age, BMI, and diabetes. A low PCS score predicted mortality in a multivariable Cox proportional hazards model [HR 0.96 (95% CI 0.92-0.99), p = 0.03]. QoL was not associated with kidney disease progression. CONCLUSION: Impaired QoL in CKD stage 4-5 patients not on dialysis is associated with cardiac biomarker levels, echocardiographic indices, and mortality.


Assuntos
Qualidade de Vida , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/epidemiologia , Idoso , Ecocardiografia , Feminino , Seguimentos , Taxa de Filtração Glomerular , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Estudos Prospectivos , Diálise Renal , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/terapia , Troponina T/sangue
2.
BMC Nephrol ; 22(1): 50, 2021 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-33541279

RESUMO

BACKGROUND: Cardiac biomarkers Troponin T (TnT) and N-terminal pro-B-type natriuretic peptide (proBNP) and abdominal aortic calcification score (AAC) are associated with cardiovascular events and mortality in patients with chronic kidney disease (CKD). The effects of cardiac biomarkers and AAC on maximal exercise capacity in CKD are unknown and were studied. METHODS: One hundred seventy-four CKD 4-5 patients not on maintenance dialysis underwent maximal bicycle ergometry stress testing, lateral lumbar radiograph to study AAC, echocardiography and biochemical assessments. RESULTS: The subjects with proportional maximal ergometry workload (WMAX%) less than 50% of the expected values had higher TnT, proBNP, AAC, left ventricular end-diastolic diameter, left ventricular mass index, E/e' and pulse pressure, and lower global longitudinal strain compared to the better performing patients. TnT (ß = - 0.09, p = 0.02), AAC (ß = - 1.67, p < 0.0001) and diabetes (ß = - 11.7, p < 0.0001) remained significantly associated with WMAX% in the multivariable model. Maximal ergometry workload (in Watts) was similarly associated with TnT and AAC in addition to age, male gender, hemoglobin and diastolic blood pressure in a respective multivariate model. AAC and TnT showed fair predictive power for WMAX% less than 50% of the expected value with AUCs of 0.70 and 0.75, respectively. CONCLUSIONS: TnT and AAC are independently associated with maximal ergometry stress test workload in patients with advanced CKD. TRIAL REGISTRATION: http://www.ClinicalTrials.gov NCT04223726.


Assuntos
Aorta Abdominal , Teste de Esforço , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/fisiopatologia , Troponina T/sangue , Calcificação Vascular/sangue , Calcificação Vascular/fisiopatologia , Idoso , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência Renal Crônica/complicações , Índice de Gravidade de Doença , Calcificação Vascular/complicações
3.
Am J Nephrol ; 51(9): 726-735, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32777781

RESUMO

BACKGROUND: Patients with advanced chronic kidney disease (CKD stage 4-5) have an increased risk of death. To study the determinants of all-cause mortality, we recruited 210 consecutive CKD stage 4-5 patients not on dialysis to the prospective Chronic Arterial Disease, quality of life and mortality in chronic KIDney injury (CADKID) study. METHODS: One hundred seventy-four patients underwent maximal bicycle ergometry stress testing and lateral lumbar radiography to study abdominal aortic calcification score and echocardiography. Carotid and femoral artery intima-media thickness and elasticity and brachial artery flow-mediated dilatation were measured in 156 patients. RESULTS: The duration of follow-up was 42 ± 17 months (range 134-2,217 days). The mean age was 61 ± 14 years, and the estimated glomerular filtration rate was 12 (11-15) mL/min/1.73 m2. Thirty-six (21%) patients died during follow-up (time to death 835 ± 372 days). Seventy-five and 21 patients had diabetes and coronary artery disease, respectively, and all but one had hypertension. In the respective multivariate proportional hazards models adjusted for age, sex, and coronary artery disease, the significant determinants of mortality were troponin T, N-terminal pro-B-type natriuretic peptide, maximal ergometry performance, abdominal aortic calcification score, E/e' ratio, and albumin. CONCLUSION: Stress ergometry performance, abdominal aortic calcification score, E/e' of echocardiography, and plasma cardiac biomarkers and albumin predict mortality in advanced CKD.


Assuntos
Doença da Artéria Coronariana/epidemiologia , Taxa de Filtração Glomerular/fisiologia , Insuficiência Renal Crônica/mortalidade , Calcificação Vascular/epidemiologia , Idoso , Biomarcadores/sangue , Espessura Intima-Media Carotídea , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/etiologia , Ecocardiografia , Teste de Esforço , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Estudos Prospectivos , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/fisiopatologia , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Troponina T/sangue , Calcificação Vascular/sangue , Calcificação Vascular/diagnóstico , Calcificação Vascular/etiologia
4.
J Physiol ; 594(23): 7127-7140, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27500951

RESUMO

KEY POINTS: High-intensity interval training (HIIT) has become popular, time-sparing alternative to moderate intensity continuous training (MICT), although the cardiac vascular and metabolic effects of HIIT are incompletely known. We compared the effects of 2-week interventions with HIIT and MICT on myocardial perfusion and free fatty acid and glucose uptake. Insulin-stimulated myocardial glucose uptake was decreased by training without any significantly different response between the groups, whereas free fatty acid uptake remained unchanged. Adenosine-stimulated myocardial perfusion responded differently to the training modes (change in mean HIIT: -19%; MICT: +9%; P = 0.03 for interaction) and was correlated with myocardial glucose uptake for the entire dataset and especially after HIIT training. HIIT and MICT induce similar metabolic and functional changes in the heart, although myocardial vascular hyperaemic reactivity is impaired after HIIT, and this should be considered when prescribing very intense HIIT for previously untrained subjects. ABSTRACT: High-intensity interval training (HIIT) is a time-efficient way of obtaining the health benefits of exercise, although the cardiac effects of this training mode are incompletely known. We compared the effects of short-term HIIT and moderate intensity continuous training (MICT) interventions on myocardial perfusion and metabolism and cardiac function in healthy, sedentary, middle-aged men. Twenty-eight healthy, middle-aged men were randomized to either HIIT or MICT groups (n = 14 in both) and underwent six cycle ergometer training sessions within 2 weeks (HIIT session: 4-6 × 30 s all-out cycling/4 min recovery, MICT session 40-60 min at 60% V̇O2 peak ). Cardiac magnetic resonance imaging (CMRI) was performed to measure cardiac structure and function and positron emission tomography was used to measure myocardial perfusion at baseline and during adenosine stimulation, insulin-stimulated glucose uptake (MGU) and fasting free fatty acid uptake (MFFAU). End-diastolic and end-systolic volumes increased and ejection fraction slightly decreased with both training modes, although no other changes in CMRI were observed. MFFAU and basal myocardial perfusion remained unchanged. MGU was decreased by training (HIIT from 46.5 to 35.9; MICT from 47.4 to 44.4 mmol 100 g-1  min-1 , P = 0.007 for time, P = 0.11 for group × time). Adenosine-stimulated myocardial perfusion responded differently to the training modes (change in mean HIIT: -19%; MICT: +9%; P = 0.03 for group × time interaction). HIIT and MICT induce similar metabolic and functional changes in the heart, although myocardial vascular hyperaemic reactivity is impaired after HIIT. This should be taken into account when prescribing very intense HIIT for previously untrained subjects.


Assuntos
Exercício Físico/fisiologia , Coração/fisiologia , Miocárdio/metabolismo , Adulto , Circulação Coronária , Ácidos Graxos não Esterificados/metabolismo , Glucose/metabolismo , Coração/diagnóstico por imagem , Hemodinâmica , Humanos , Insulina/metabolismo , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons
5.
J Inherit Metab Dis ; 39(1): 67-74, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26112752

RESUMO

Mitochondrial mutations impair glucose oxidation and increase glucose uptake in cell cultures and lead to cardiomyopathy in patients. Here we characterize cardiac glucose uptake in 14 patients with the m.3243A > G mutation in mitochondrial DNA. The 14 patients with m.3243A > G and 13 controls were similar in age, physical activity and body mass index. Ten patients had diabetes. Left ventricular glucose uptake per tissue mass (LVGU) was measured with 2-[(18) F]fluoro-2-deoxyglucose positron emission tomography during euglycemic hyperinsulinemia. Cardiac morphology and function were assessed with magnetic resonance imaging. We found that the LVGU was 25% lower in the patients than that in the controls (P = 0.029). LVGU was inversely correlated with mutation heteroplasmy, glycated haemoglobin and fasting lactate in patients. The seven patients with mutation heteroplasmy ≥ 49% had 44% lower LVGU than the seven patients with heteroplasmy < 49%. This difference remained significant after adjustment for concurrent free fatty acid concentration or glycated haemoglobin or glucose uptake in skeletal muscle or all (p < 0.048 [All]). Patients with m.3243A > G had a lower stroke volume and a higher heart rate than the controls, whereas cardiac output and work were similar. Myocardial glucose uptake is not increased but decreased with a threshold effect pattern in patients with the m.3243A > G mutation. The glucose hypometabolism adds to the impaired cardiac energetics and likely contributes to the progression of the mitochondrial cardiomyopathy.


Assuntos
DNA Mitocondrial/genética , Glucose/metabolismo , Mitocôndrias/genética , Mutação/genética , Miocárdio/metabolismo , Glicemia/metabolismo , Estudos de Casos e Controles , Diabetes Mellitus/genética , Diabetes Mellitus/metabolismo , Epitélio/metabolismo , Feminino , Teste de Tolerância a Glucose/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo
6.
Nephron ; 146(5): 439-448, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35139517

RESUMO

INTRODUCTION: Chronic kidney disease (CKD) has a profound effect on patients' health-related quality of life (QoL). Longitudinal studies on QoL in CKD are scarce and have explored selected patients on renal replacement therapy (RRT). We studied the evolution of QoL in patients with advanced CKD transitioning to dialysis and transplantation in a prospective follow-up study. METHODS: A total of 100 participants of the Chronic Arterial Disease, Quality of Life, and Mortality in Chronic Kidney Injury (CADKID) study were enrolled in the study. Kidney Disease Quality of Life Short Form, biochemistry, and echocardiography were obtained at baseline and after a median interval of 33 (range 12-85) months. RESULTS: At the time of the follow-up QoL assessment, 32 patients were not receiving RRT, 30 were on hemodialysis (HD), 19 on peritoneal dialysis (PD), and 19 had received a kidney transplant. Among kidney transplant recipients (KTRs), "Burden of Kidney Disease" and "General Health" domains improved compared to patients who initiated HD (p < 0.0001 and p = 0.007, respectively), PD (p = 0.0005 and p = 0.03, respectively), or remained in predialysis care (p = 0.009 and p = 0.003, respectively) while "Effects of Kidney Disease" improved compared to those who started HD (p = 0.004) or PD (p = 0.002). The change in Short Form-36 (SF-36) Physical Component Summary was not different between patients on different treatment modalities. Higher plasma albumin and cholesterol levels were associated with improved QoL in "Symptoms/Problems" (r = 0.28, p = 0.005, and r = 0.30, p = 0.004, respectively) and "Effects of Kidney Disease" (r = 0.27, p = 0.008, and r = 0.24, p = 0.03, respectively). CONCLUSION: QoL improved in KTRs in kidney disease-specific domains compared to patients initiating dialysis or those without RRT. Plasma albumin and lipids were associated with QoL over time.


Assuntos
Falência Renal Crônica , Insuficiência Renal Crônica , Seguimentos , Humanos , Falência Renal Crônica/terapia , Estudos Prospectivos , Qualidade de Vida , Diálise Renal , Insuficiência Renal Crônica/terapia , Albumina Sérica
7.
Eur J Cardiovasc Prev Rehabil ; 16(2): 161-3, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19276983

RESUMO

BACKGROUND AND DESIGN: The purpose of this randomized controlled cross-over study was to determine the acute effects of high doses of alcoholic beverages on circulating markers related to atherosclerosis and fibrinolysis. METHODS: Twenty-two healthy men consumed a high dose (8.1+/-0.9 dl) of alcohol-containing red wine and dealcoholized red wine, and an equal ethanol dose of cognac (2.4+/-0.3 dl). Blood samples were taken before and shortly after interventions. RESULTS: Red wine, unlike dealcoholized red wine and cognac, increased tissue plasminogen activator inhibitor-1 levels significantly, indicating an acute inhibition of fibrinolysis after a high dose. CONCLUSION: Findings may explain the increased risk of cardiovascular mortality among binge drinkers.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Aterosclerose/etiologia , Doenças Cardiovasculares/etiologia , Etanol/efeitos adversos , Fibrinólise/efeitos dos fármacos , Vinho/efeitos adversos , Adulto , Consumo de Bebidas Alcoólicas/sangue , Aterosclerose/sangue , Biomarcadores/sangue , Doenças Cardiovasculares/sangue , Estudos Cross-Over , Etanol/sangue , Humanos , Mediadores da Inflamação/sangue , Masculino , Inibidor 1 de Ativador de Plasminogênio/sangue , Adulto Jovem
8.
Cardiovasc Ultrasound ; 6: 25, 2008 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-18522727

RESUMO

BACKGROUND: The cardioprotective effects of certain alcoholic beverages are partly related to their polyphenol content, which may improve the vasodilatory reactivity of arteries. Effect of cognac on coronary circulation, however, remains unknown. The purpose of this randomized controlled cross-over study was to determine whether moderate doses of cognac improve coronary reactivity as assessed with cold pressor testing (CPT) and coronary flow reserve (CFR) measurement. METHODS: Study group consisted of 23 subjects. Coronary flow velocity and epicardial diameter was assessed using transthoracic echocardiography at rest, during CPT and adenosine infusion-derived CFR measurements before drinking, after a moderate (1.2 +/- 0.1 dl) and an escalating high dose (total amount 2.4 +/- 0.3 dl) of cognac. To explore the bioavailability of antioxidants, the antioxidant contents of cognac was measured and the absorption from the digestive tract was verified by plasma antioxidant capacity determination. RESULTS: Serum alcohol levels increased to 1.2 +/- 0.2 per thousand and plasma antioxidant capacity from 301 +/- 43.9 micromol/l to 320 +/- 25.0 micromol/l by 7.6 +/- 11.8%, (p = 0.01) after high doses of cognac. There was no significant change in flow velocity during CPT after cognac ingestion compared to control day. CFR was 4.4 +/- 0.8, 4.1 +/- 0.9 (p = NS), and 4.5 +/- 1.2 (p = NS) before drinking and after moderate and high doses on cognac day, and 4.5 +/- 1.4, and 4.0 +/- 1.2 (p = NS) on control day. CONCLUSION: Cognac increased plasma antioxidant capacity, but it had no effect on coronary circulation in healthy young men. TRIAL REGISTRATION: NCT00330213.


Assuntos
Bebidas Alcoólicas , Antioxidantes/metabolismo , Velocidade do Fluxo Sanguíneo , Circulação Coronária/efeitos dos fármacos , Doença das Coronárias/fisiopatologia , Etanol/administração & dosagem , Vasodilatação/efeitos dos fármacos , Adulto , Consumo de Bebidas Alcoólicas , Análise de Variância , Antioxidantes/administração & dosagem , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Estudos Cross-Over , Finlândia , Humanos , Masculino , Probabilidade , Valores de Referência , Sensibilidade e Especificidade , Ultrassonografia Doppler de Pulso , Resistência Vascular
9.
Ultrasound Med Biol ; 33(3): 362-70, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17188799

RESUMO

Transthoracic Doppler echocardiography (TTE) has been introduced as a noninvasive tool to measure coronary flow velocity reserve (CFVR). Velocity measurement, however, fails to take into account epicardial coronary artery vasodilation during hyperemia and this may cause underestimation of CFVR measurements. Therefore, we sought to determine whether the vasodilation of epicardial coronary artery can be measured during cold pressor test (CPT) and adenosine infusion simultaneously with the flow velocity measurement using TTE. We studied 41 healthy nonsmoking men with a linear high-frequency 8.0-MHz transducer. The CPT and adenosine infusion dilated the diameter of the distal left anterior descending coronary artery (LAD) from 1.4 +/- 0.4 mm to 1.5 +/- 0.4 mm (14 +/- 13%, p < 0.01) and from 1.4 +/- 0.4 mm to 1.8 +/- 0.5 mm (31 +/- 19%, p < 0.01), respectively. The CPT increased flow velocity and calculated coronary blood flow rate (velocity time integral x cross-sectional area) from 0.23 +/- 0.05 m/s to 0.36 +/- 0.13 m/s (31 +/- 34%, p < 0.01) and from 8.1 +/- 4.2 mL/min to 11.4 +/- 6.0 mL/min (47 +/- 51%, p < 0.01). CFVR and calculated coronary blood flow rate reserve were 3.9 +/- 1.0 and 6.0 +/- 1.9, respectively. In Bland-Altman analysis, velocity measurements underestimated the vasodilation response of the CPT and adenosine compared with the measurements where epicardial diameter dilation was taken into account. Intra- and interobserver variability of diameter measurements was low (coefficient of variation [CV] 2.6 to 6.5%). Day-to-day, within-day and intersonographer variabilities were of similar magnitude (CV 4.6 to 8.2%), suggesting good reproducibility. This study demonstrates that TTE can be used to assess changes in both epicardial coronary artery diameter and flow velocity simultaneously in the distal LAD artery.


Assuntos
Vasos Coronários/diagnóstico por imagem , Ecocardiografia Doppler/métodos , Vasodilatação/fisiologia , Adenosina/administração & dosagem , Adulto , Velocidade do Fluxo Sanguíneo/fisiologia , Temperatura Baixa , Circulação Coronária/fisiologia , Vasos Coronários/efeitos dos fármacos , Humanos , Imersão , Infusões Intravenosas , Masculino , Pericárdio/diagnóstico por imagem , Reprodutibilidade dos Testes , Vasodilatação/efeitos dos fármacos , Vasodilatadores/administração & dosagem
10.
J Clin Endocrinol Metab ; 91(11): 4689-95, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16926257

RESUMO

CONTEXT AND OBJECTIVE: Ectopic fat accumulation within and around the myocardial wall has been implicated in the pathogenesis of heart disease in obesity. We evaluated myocardial and epicardial fat, left ventricular (LV) function, and metabolic risk factors in nine (five lean, four moderately obese) men. METHODS: Myocardial fat percent was quantified in the septum by proton magnetic resonance spectroscopy. Reproducibility was assessed by triplicate systolic and diastolic measurements. LV parameters and epicardial fat were determined by magnetic resonance imaging. Waist-to-hip ratio and liver enzymes (alanine transaminase) were used as surrogate markers of visceral and liver fat contents. RESULTS: Myocardial fat (2.1 +/- 0.5 vs. 0.8 +/- 0.1, P = 0.03) and epicardial fat (120 +/- 33 vs. 55 +/- 12 g, P = 0.08) were higher in obese than lean subjects. Individuals with above-median alanine transaminase values had a 4-fold elevation in myocardial fat. The coefficient of variation of repeated myocardial fat percent determinations was 17 +/- 3 and 23 +/- 3% in systole and diastole, respectively. Myocardial fat was correlated with free fatty acid (FFA) levels (r = 0.76; P = 0.017), epicardial fat (r = 0.69; P = 0.042), and waist-to-hip ratio (r = 0.70; P = 0.035), and it showed a tendency to associate positively with LV work. Epicardial fat was associated with peripheral vascular resistance (positively) and the cardiac index (negatively). FFA levels were significantly correlated with LV mass (r = 0.72; P = 0.030) and forward work (r = 0.74; P = 0.023). CONCLUSIONS/INTERPRETATION: The accumulation of triglyceride in and around the myocardium of moderately obese individuals is significant, and it is related to FFA exposure, generalized ectopic fat excess, and peripheral vascular resistance. These changes precede LV overload and hypertrophy.


Assuntos
Tecido Adiposo/anatomia & histologia , Ácidos Graxos não Esterificados/sangue , Miocárdio/química , Obesidade/complicações , Pericárdio/anatomia & histologia , Triglicerídeos/análise , Função Ventricular Esquerda/fisiologia , Adulto , Alanina Transaminase/análise , Doenças Cardiovasculares/etiologia , Coristoma/etiologia , Coração/diagnóstico por imagem , Humanos , Fígado/química , Fígado/enzimologia , Fígado/metabolismo , Pessoa de Meia-Idade , Obesidade/sangue , Obesidade/diagnóstico por imagem , Radiografia , Magreza/sangue , Relação Cintura-Quadril
11.
Front Physiol ; 6: 389, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26733882

RESUMO

Dysfunction of the right ventricle (RV) plays a crucial role in the outcome of various cardiovascular diseases. Previous studies on RV metabolism are sparse although evidence implies it may differ from left ventricular (LV) metabolism. Therefore, the aims of this study were (1) to determine predictors of RV glucose uptake (GU) and free fatty acid uptake (FFAU) and (2) to compare them to predictors of LV metabolism in healthy middle-aged men. Altogether 28 healthy, sedentary, middle-aged (40-55 years) men were studied. Insulin-stimulated GU and fasting FFAU were measured by positron emission tomography and RV and LV structural and functional parameters by cardiac magnetic resonance. Several parameters related to whole-body health were also measured. Predictors of RV and LV metabolism were determined by pairwise correlation analysis, lasso regression models, and variable clustering using heatmap. RVGU was most strongly predicted by age and moderately by RV ejection fraction (EF). The strongest determinants of RVFFAU were exercise capacity (peak oxygen uptake), resting heart rate, LVEF, and whole-body insulin-stimulated glucose uptake rate. When considering LV metabolism, age and RVEF were associated also with LVGU. In addition, LVGU was strongly, and negatively, influenced by whole-body insulin-stimulated glucose uptake rate. LVFFAU was predicted only by LVEF. This study shows that while RV and LV metabolism have shared characteristics, they also have unique properties. Age of the subject should be taken into account when measuring myocardial glucose utilization. Ejection fraction is related to myocardial metabolism, and even so that RVEF may be more closely related to GU of both ventricles and LVEF to FFAU of both ventricles, a finding supporting the ventricular interdependence. However, only RV fatty acid utilization associates with exercise capacity so that better physical fitness in a relatively sedentary population is related with decreased RV fat metabolism. To conclude, this study highlights the need for further study designed specifically on less-known RV, as the results on LV metabolism and physiology may not be directly applicable to the RV.

12.
Front Physiol ; 3: 17, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22347864

RESUMO

BACKGROUND: Levosimendan is a calcium sensitizer that has been shown to prevent myocardial contractile depression in patients post cardiac surgery. This drug exhibits an anti-apoptotic property; however, the underlying mechanism remains elusive. In this report, we characterized the myocardial protective of levosimendan in preventing cardiomyocyte apoptosis and post-operative stunning in an experimental ischemia-reperfusion model. METHODS: Three groups of pigs (n = 8 per group) were subjected to 40 min of global, cardioplegic ischemia followed by 240 min of reperfusion. Levosimendan (65 µg/kg body weight) was given to pigs by intravenous infusion (L-IV) before ischemia or intracoronary administration during ischemia (L-IC). The Control group did not receive any levosimendan. Echocardiography was used to monitor cardiac function in all groups. Apoptosis levels were assessed from the left ventricle using the terminal transferase mediated dUTP nick end labeling (TUNEL) assay and immunocytochemical detection of Caspase-3. RESULTS: Pigs after ischemia-reperfusion had a much higher TUNEL%, suggesting that our treatment protocol was effective. Levels of apoptosis were significantly increased in Control pigs that did not receive any levosimendan (0.062 ± 0.044%) relative to those received levosimendan either before (0.02 ± 0.017%, p = 0.03) or during (0.02 ± 0.017%, p = 0.03) the ischemia phase. Longitudinal left ventricular contraction in pigs that received levosimendan before ischemia (0.75 ± 0.12 mm) was significantly higher than those received levosimendan during ischemia (0.53 ± 0.11 mm, p = 0.003) or Control pigs (0.54 ± 0.11 mm, p = 0.01). CONCLUSION: Our results suggested that pigs received levosimendan displayed a markedly improved cell survival post I-R. The effect on cardiac contractility was only significant in our perfusion heart model when levosimendan was delivered intravenously before ischemia.

13.
Cardiovasc Ther ; 30(6): 333-41, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21884010

RESUMO

INTRODUCTION: The metabolic modulator trimetazidine (TMZ) has been suggested to induce a metabolic shift from myocardial fatty acid oxidation (FAO) to glucose utilization, but this mechanism remains unproven in humans. The oxidation of plasma derived FA is commonly measured in humans, whereas the contribution of FA from triglycerides stored in the myocardium has been poorly characterized. AIMS: To verify the hypothesis that TMZ induces a metabolic shift, we combined positron emission tomography (PET) and magnetic resonance spectroscopy ((1)H-MRS) to measure myocardial FAO from plasma and intracellular lipids, and myocardial glucose metabolism. Nine obese subjects were studied before and after 1 month of TMZ treatment. Myocardial glucose and FA metabolism were assessed by PET with (18)F-fluorodeoxyglucose and (11)C-palmitate. (1)H-MRS was used to measure myocardial lipids, the latter being integrated into the PET data analysis to quantify myocardial triglyceride turnover. RESULTS: Myocardial FAO derived from intracellular lipids was at least equal to that of plasma FAs (P = NS). BMI and cardiac work were positively associated with the oxidation of plasma derived FA (P ≤ 0.01). TMZ halved total and triglyceride-derived myocardial FAO (32.7 ± 8.0 to 19.6 ± 4.0 µmol/min and 23.7 ± 7.5 to 10.3 ± 2.7 µmol/min, respectively; P ≤ 0.05). These changes were accompanied by increased cardiac efficiency since unchanged LV work (1.6 ± 0.2 to 1.6 ± 0.1 Watt/g × 10(2), NS) was associated with decreased work energy from the intramyocardial triglyceride oxidation (1.6 ± 0.5 to 0.4 ± 0.1 Watt/g × 10(2), P = 0.036). CONCLUSIONS: In obese subjects, we demonstrate that myocardial intracellular triglyceride oxidation significantly provides FA-derived energy for mechanical work. TMZ reduced the oxidation of triglyceride-derived myocardial FAs improving myocardial efficiency.


Assuntos
Ácidos Graxos não Esterificados/metabolismo , Obesidade/tratamento farmacológico , Trimetazidina/farmacologia , Vasodilatadores/farmacologia , Adulto , Idoso , Índice de Massa Corporal , Feminino , Glucose/metabolismo , Testes de Função Cardíaca , Hemodinâmica , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Palmitatos/metabolismo , Tomografia por Emissão de Pósitrons
14.
Front Physiol ; 3: 6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22363288

RESUMO

PURPOSE: Beneficial mechanisms of bone marrow cell (BMC) therapy for acute ST-segment elevation myocardial infarct (STEMI) are largely unknown in humans. Therefore, we evaluated the feasibility of serial positron emission tomography (PET) and MRI studies to provide insight into the effects of BMCs on the healing process of ischemic myocardial damage. METHODS: Nineteen patients with successful primary reteplase thrombolysis (mean 2.4 h after symptoms) for STEMI were randomized for BMC therapy (2.9 × 10(6) CD34+ cells) or placebo after bone marrow aspiration in a double-blind, multi-center study. Three days post-MI, coronary angioplasty, and paclitaxel eluting stent implantation preceded either BMC or placebo therapy. Cardiac PET and MRI studies were performed 7-12 days after therapies and repeated after 6 months, and images were analyzed at a central core laboratory. RESULTS: In BMC-treated patients, there was a decrease in [(11)C]-HED defect size (-4.9 ± 4.0 vs. -1.6 ± 2.2%, p = 0.08) and an increase in [(18)F]-FDG uptake in the infarct area at risk (0.06 ± 0.09 vs. -0.05 ± 0.16, p = 0.07) compared to controls, as well as less left ventricular dilatation (-4.4 ± 13.3 vs. 8.0 ± 16.7 mL/m(2), p = 0.12) at 6 months follow-up. However, BMC treatment was inferior to placebo in terms of changes in rest perfusion in the area at risk (-0.09 ± 0.17 vs. 0.10 ± 0.17, p = 0.03) and infarct size (0.4 ± 4.2 vs. -5.1 ± 5.9 g, p = 0.047), and no effect was observed on ejection fraction (p = 0.37). CONCLUSION: After the acute phase of STEMI, BMC therapy showed only minor trends of long-term benefit in patients with rapid successful thrombolysis. There was a trend of more decrease in innervation defect size and enhanced glucose metabolism in the infarct-related myocardium and also a trend of less ventricular dilatation in the BMC-treated group compared to placebo. However, no consistently better outcome was observed in the BMC-treated group compared to placebo.

15.
Ann Thorac Surg ; 92(4): 1351-7, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21958782

RESUMO

BACKGROUND: Retrograde delivery is associated with inadequate perfusion of cardioplegia to all regions of the heart, but the effects on cardiomyocyte death and functional outcome remain unknown. We compared antegrade and retrograde cardioplegia in a randomized clinical trial to see whether it has effect on cardiomyocyte apoptosis and left ventricular function. METHODS: Patients underwent elective aortic valve replacement surgery due to aortic valve stenosis. They were randomly allocated to receive antegrade (n = 10) or retrograde (n = 10) cardioplegia. Apoptotic cardiomyocytes (terminal transferase-mediated dUTP nick end labeling, caspase activation) and RNA levels of apoptosis-regulating proteins were studied in transmyocardial biopsies obtained before and after the operation. Magnetic resonance imaging and transesophageal echocardiography were performed, and cardiac enzymes were measured. RESULTS: Clinical outcome and cardiac enzyme release were comparable between the groups. Cardiomyocyte apoptosis was significantly increased (terminal transferase-mediated dUTP nick end labeling) in the left ventricle after the operation in the retrograde, but not in the antegrade group (respectively, 0.00% [0.039%] versus 0.092% [0.205%], p = 0.01; and 0.00% [0.00%] versus 0.023% [0.054%], p = 0.14). Expression of apoptosis-regulating proteins BAX, BAD, and BCL-2 were comparable between groups. By transesophageal echocardiography, the systolic mitral annulus movement was decreased immediately after the operation in the retrograde group. By magnetic resonance imaging, the left ventricle mass index was reduced preoperatively to 9 months postoperatively in the antegrade group. CONCLUSIONS: In contrast to antegrade cardioplegia, retrograde cardioplegia is associated with increased cardiomyocyte apoptosis, impaired immediate postoperative systolic function, and lack of long-term favorable left ventricle remodeling after aortic valve replacement, suggesting inadequate myocardial protection.


Assuntos
Estenose da Valva Aórtica/cirurgia , Apoptose , Parada Cardíaca Induzida/efeitos adversos , Implante de Prótese de Valva Cardíaca/efeitos adversos , Ventrículos do Coração/patologia , Miócitos Cardíacos/patologia , Disfunção Ventricular Esquerda/diagnóstico , Idoso , Estenose da Valva Aórtica/diagnóstico , Biópsia , Ecocardiografia Transesofagiana , Feminino , Seguimentos , Parada Cardíaca Induzida/métodos , Implante de Prótese de Valva Cardíaca/métodos , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Humanos , Marcação In Situ das Extremidades Cortadas , Imagem Cinética por Ressonância Magnética/métodos , Masculino , Prognóstico , Volume Sistólico , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/fisiopatologia , Função Ventricular Esquerda/fisiologia
16.
Clin Physiol Funct Imaging ; 30(2): 89-97, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19909300

RESUMO

BACKGROUND: Cardiac magnetic resonance imaging (CMR) is a promising method for detecting coronary artery disease (CAD). The first reports of new diagnostic techniques indicated generally unrealistic diagnostic performance relying on retrospectively observed cut-off values of quantitative parameters. Although visual analysis of CMR is the most applicable method for clinical work, its diagnostic performance is not fully elucidated for study components such as wall motion, perfusion and late enhancement in patients with different severity of CAD. METHODS: A total of 30 subjects including 20 patients with CAD and 10 healthy volunteers were selected for the study. Of the patients, ten had stable CAD, five confirmed myocardial infarction (MI) without Q-waves in electrocardiogram (ECG) and five confirmed MI with Q-waves in ECG. All patients underwent coronary angiography and CMR for evaluating resting wall motion, rest and stress perfusion and late enhancement. RESULTS: Combining the data from the three CMR techniques, 12 out of 20 patients were correctly identified as having CAD, and all controls were found to be healthy. Sensitivity, specificity, accuracy, positive and negative predictive values were 60.0%, 100.0%, 73.0%, 100.0% and 55.6%, respectively. Of the CMR components, resting wall motion and late enhancement gave the most diagnostic yield. CONCLUSIONS: We conclude that evaluation of CAD is feasible in patients with different severity of CAD using visually analysed CMR, especially when available CMR methodologies are combined together.


Assuntos
Doença da Artéria Coronariana/patologia , Doença da Artéria Coronariana/fisiopatologia , Teste de Esforço , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/normas , Adulto , Idoso , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Eletrocardiografia , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Clin Physiol Funct Imaging ; 29(4): 229-40, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19302226

RESUMO

Cardiac magnetic resonance imaging (CMR) has rapidly gained acceptance as an accurate, reproducible and non-invasive imaging method for assessment of a wide range of cardiovascular diseases. However, CMR has not been used widely for diagnostic purposes in valvular heart disease (VHD). Unlike echocardiography it has no body habitus-related limitations and can thus be used to complement echocardiography. It is an especially good alternative for clinical follow-up in patients with VHD, as it allows accurate measurement of valvular dysfunction and related ventricular burden. Additionally, CMR is an ideal method for evaluating complex congenital heart disease and determining the significance of its components. It can also be used to study the physiological course of valvular dysfunction and response to therapeutic interventions. In this review, we present a basic introduction to CMR methodology, including its advantages and potential problems, and the physiology and quantification in VHD. We also discuss clinical applications of CMR in VHD. Furthermore, we describe how a CMR study statement should be structured in order to increase clinical use of this valuable methodology in cardiology.


Assuntos
Doenças das Valvas Cardíacas/diagnóstico , Valvas Cardíacas/patologia , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Humanos
18.
Am J Cardiol ; 103(12): 1721-6, 2009 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-19539082

RESUMO

Obesity is associated with increased fatty acid uptake in the myocardium, and this may have deleterious effects on cardiac function. The aim of this study was to evaluate how weight loss influences myocardial metabolism and cardiac work in obese adults. Thirty-four obese (mean body mass index 33.7 +/- 0.7 kg/m(2)) but otherwise healthy subjects consumed a very low calorie diet for 6 weeks. Cardiac substrate metabolism and work were measured before and after the diet. Myocardial fatty acid uptake was measured in 18 subjects using fluorine-18-fluoro-6-thia-heptadecanoic acid and positron emission tomography, and myocardial glucose uptake was measured in 16 subjects using fluorine-18-2-fluoro-2-deoxyglucose. Myocardial structure and cardiac function were measured using magnetic resonance imaging. Consumption of the very low calorie diet decreased weight (-11.2 +/- 0.6 kg, p <0.0001). Myocardial fatty acid uptake decreased from 4.2 +/- 0.4 to 2.9 +/- 0.2 micromol/100 g/min (p <0.0001). Myocardial mass decreased by 7% (p <0.005), and cardiac work decreased by 26% (p <0.0001). Whole-body insulin sensitivity increased by 33% (p <0.01), but insulin-stimulated myocardial glucose uptake remained unchanged (p = 0.90). Myocardial triglyceride content decreased by 31% (n = 8, p = 0.076). In conclusion, weight reduction decreases myocardial fatty acid uptake in parallel with myocardial mass and cardiac work. These results show that the increased fatty acid uptake found in the hearts of obese patients can be reversed by weight loss.


Assuntos
Ácidos Graxos/farmacocinética , Ventrículos do Coração/metabolismo , Contração Miocárdica/fisiologia , Miocárdio/metabolismo , Obesidade/dietoterapia , Disfunção Ventricular Esquerda/prevenção & controle , Redução de Peso/fisiologia , Adulto , Testes Calóricos , Dieta com Restrição de Gorduras , Feminino , Seguimentos , Glucose/metabolismo , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Obesidade/complicações , Tomografia por Emissão de Pósitrons , Prognóstico , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/fisiopatologia , Função Ventricular Esquerda/fisiologia
19.
Dig Dis Sci ; 52(7): 1678-84, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17385028

RESUMO

Normal values of extra-esophageal reflux are difficult to determine owing to variation in the location of the proximal electrode, limited information on the ingestion of acidic food, different exclusion periods for meals, and poor reproducibility of measurement of extra-esophageal reflux. We studied whether ambulatory esophageal pH testing is disturbed by acidic food ingestion. Eighteen healthy subjects were enrolled in standard dual-channel esophageal pH tests (recorder 1). Ten subjects were equipped with another pH device (recorder 2), positioned to measure extra-esophageal reflux. The subjects were exposed to controlled ingestion of different acidic food or liquid for five 1-min periods. The present study showed that acidic food ingestion for 5 min has a significant effect on the outcome of standard dual-channel ambulatory pH testing. Reflux occurs equally on proximal channels during ingestion of acidic food, whether the proximal channel position is normal or 2 cm above the upper esophageal sphincter. We recommend avoiding acidic food intake during esophageal pH testing.


Assuntos
Bebidas , Monitoramento do pH Esofágico/normas , Alimentos , Refluxo Gastroesofágico/diagnóstico , Adulto , Reações Falso-Positivas , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Fatores de Tempo
20.
Atherosclerosis ; 195(2): e176-81, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17662293

RESUMO

BACKGROUND: Red wine consumption is associated with reduced cardiovascular disease mortality. Its cardioprotective properties may be partly related to its ability to improve endothelial function. The purpose of this randomized controlled cross-over study was to determine whether moderate doses of red wine and de-alcoholized red wine improve coronary flow velocity reserve (CFR). METHODS: Using transthoracic Doppler echocardiography, 176 CFR measurements were made in 22 healthy men before and after ingestion of a moderate (4.0+/-0.4 dl) and an escalating high dose (total amount 8.1+/-0.9 dl) of alcohol-containing red wine and de-alcoholized red wine, which contained similar amounts of phenolic substances. The difference in plasma antioxidant capacity was determined by colorimetric assay kit. RESULTS: Red wine increased CFR from 3.8+/-1.4 to 4.5+/-1.4 (p<0.01) and 4.0+/-1.2 (p=NS) after moderate and high doses, respectively; whereas de-alcoholized red wine had no significant effects on CFR (4.0+/-0.7, 4.3+/-1.3 and 4.5+/-1.4, respectively). Plasma antioxidant capacity increased significantly after high dose of red wine (27.5+/-14.7%, p<0.001), but not after de-alcoholized red wine (0.5+/-10.5%, p=NS) despite similar amounts of phenolic substances. Differences between CFR and plasma antioxidant capacities before and after drinking had no significant association. CONCLUSIONS: A moderate dose of red wine, but not de-alcoholized red wine increases CFR. The increase of CFR is probably mediated by other than direct antioxidant properties of polyphenols, because the simultaneous increase of CFR and plasma antioxidant capacity were not associated.


Assuntos
Circulação Coronária/efeitos dos fármacos , Vasos Coronários/efeitos dos fármacos , Vinho , Adulto , Consumo de Bebidas Alcoólicas , Antioxidantes/análise , Estudos Cross-Over , Relação Dose-Resposta a Droga , Ecocardiografia , Ecocardiografia Doppler , Humanos , Masculino , Fluxo Sanguíneo Regional/efeitos dos fármacos
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