RESUMEN
AIMS: We aimed to investigate whether left bundle branch block (LBBB) is related to new-onset left ventricle (LV) wall motion abnormalities during treatment in hypertensive patients with electrocardiographic (ECG) defined left ventricular hypertrophy (LVH). METHODS AND RESULTS: 960 patients with essential hypertension and ECG-LVH participating in the LIFE Echo Sub-study were investigated at baseline and annually with echocardiography, during randomized antihypertensive therapy. After excluding patients with LV wall motion abnormalities at baseline and patients developing new-onset LBBB during study time, we investigated 784 patients. The participants with (n = 32) and without (n = 752) LBBB were similar regarding most baseline variables. Logistic regression models controlling for LV mass index, Framingham risk score, and randomized treatment assignment were used to assess the odds ratio of developing new-onset abnormal LV wall motion on annual follow-up echocardiograms. The likelihood of developing new global LV wall motion abnormalities in patients with LBBB was not higher compared to those without LBBB except at year 5 (p = .002). The likelihood of developing new segmental LV wall motion abnormalities in patients with LBBB was however higher compared to patients without LBBB after 1 year (OR = 3.1, 95% CI = 0.7-14.2, p = .173); 2 years (OR = 6.9, 2.1-22.4, p = .003); 3 years (OR = 5.3, 2.0-14.3, p < .001), 4 years (OR = 4.0, 1.6-10.3, p = .003 and 5 years (OR = 4.1, 1.0-16.2, p = .394) of treatment. CONCLUSION: Among patients with ECG-LVH, undergoing antihypertensive treatment, the presence of LBBB independently identifies individuals with â¼3- to 7-fold greater odds of developing new segmental abnormal LV wall motion. These findings suggest that LBBB may be a marker for progressive myocardial disease.
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Bloqueo de Rama/complicaciones , Ventrículos Cardíacos/fisiopatología , Hipertensión/complicaciones , Hipertrofia Ventricular Izquierda/diagnóstico , Anciano , Antihipertensivos/uso terapéutico , Cardiomiopatías , Progresión de la Enfermedad , Ecocardiografía , Electrocardiografía , Femenino , Ventrículos Cardíacos/patología , Humanos , Hipertensión/tratamiento farmacológico , Hipertensión/fisiopatología , Hipertrofia Ventricular Izquierda/diagnóstico por imagen , Masculino , Persona de Mediana Edad , PronósticoRESUMEN
BACKGROUND: Subclinical cardiac involvement diagnosis is important for long term management of rheumatoid arthritis (RA) patients. Recently, 2D speckle tracking echocardiography (STE) allows non invasive and angle-independent measurement of left ventricular (LV) dimensions and regional myocardial strain (ε). The aim of this study was to assess whether STE can be useful to detect subclinical cardiac involvement in RA patients. METHODS: We studied 22 RA patients (10 M, 12 F, aged 46 ± 12 years) without clinical evidence of coronary artery disease (CAD) and 20 healthy controls matched for age and sex by STE. LV end-systolic longitudinal and radial ε from apical 4-chamber view were analyzed using available software (QLAB 6.0). RESULTS: Standard echo and Doppler parameters did not differ between the 2 groups. Tissue Doppler Imaging (TDI) showed a significant reduction of S', E' and E'/A' ratio from the basal septum and lateral mitral annulus in RA patients. LV end-systolic radial and longitudinal ε of basal-lateral, basal- and mid-septal, mid-lateral and apical segments were significantly reduced compared to controls. CONCLUSIONS: Our data indicate that LV end-systolic radial and longitudinal ε are reduced in RA patients without CAD despite normal standard echo. Non invasive evaluation of LV function by STE appears to be useful to detect subclinical cardiac involvement in comparison to conventional 2D echoDoppler, representing a promising new modality to follow-up RA patients for cardiac involvement.
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Artritis Reumatoide/complicaciones , Ecocardiografía/métodos , Disfunción Ventricular Izquierda/diagnóstico por imagen , Artritis Reumatoide/fisiopatología , Ecocardiografía Doppler , Femenino , Humanos , Masculino , Contracción Miocárdica , Medición de Riesgo , Disfunción Ventricular Izquierda/etiología , Función Ventricular IzquierdaRESUMEN
BACKGROUND: Body weight supported treadmill training (BWSTT) assisted with a robotic driven gait orthosis (DGO) is an emerging tool in rehabilitating patients with lost sensorimotor function. Few information about the effects of BWSTT on cardiovascular system are available. The purpose of this study was to determine the effects of BWSTT on: 1) left ventricular (LV) systo-diastolic function; 2) coronary flow reserve (CFR); 3) endothelial function in patients with lost sensorimotor function due to neurologic lesions. METHODS: Fourteen adults (males 10, age 50.6±17.1years) with motor incomplete spinal cord injuries (SCI) due to trauma or spondylotic diseases underwent standard echocardiographic examination, non invasive assessment of CFR by dipyridamole stress echo and determination of plasma asymmetric dimethylarginine (ADMA) levels at baseline and after 6weeks of BWSTT. RESULTS: At post training evaluation we observed lower LV end-diastolic (P=0.0164) and end-systolic volumes (P=0.0029) with increased ejection fraction (EF) (P=0.0266). We also observed a LV interventricular septum (IVS) (P=0.00469) increase. At the same time, we detected an improvement of LV diastolic function as witnessed by the reduction of isovolumic relaxation time (IVRT) (P=0.0404) and deceleration time (DT) (P=0.0405) with an increased E/A ratio (P=0.0040). Improved CFR (P=0.020) and reduced plasma ADMA levels (P=0.0005) have been observed too, in association with a reduction of the inflammatory status (C-reactive protein (CRP) (P=0.0022) and erythrocyte sedimentation rate (ESR) (P=0.0005)). CONCLUSION: For the first time, this study demonstrated that 6weeks of BWSTT improved not only the sensorimotor function but also systo-diastolic LV function, CFR and endothelial dysfunction associated with a reduction of the inflammatory status in patients with incomplete SCI.
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Fenómenos Fisiológicos Cardiovasculares , Terapia por Ejercicio/métodos , Aptitud Física/fisiología , Robótica/métodos , Traumatismos de la Médula Espinal/fisiopatología , Traumatismos de la Médula Espinal/rehabilitación , Adulto , Anciano , Arginina/análogos & derivados , Arginina/sangre , Circulación Coronaria/fisiología , Diástole/fisiología , Ecocardiografía , Endotelio Vascular/fisiología , Terapia por Ejercicio/instrumentación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Robótica/instrumentación , Función Ventricular Izquierda/fisiologíaRESUMEN
PURPOSE: The feasibility of coronary function estimation by single photon emission computed tomography (SPECT) has been recently demonstrated. The aim of this study was to apply SPECT imaging in patients with previous Kawasaki disease (KD) to assess the coronary functional status at long-term follow-up of the acute phase of the disease. METHODS: Sixteen children with a history of KD underwent 99mTc-sestamibi imaging at rest and during the cold pressor test (CPT). Myocardial blood flow (MBF) was estimated by measuring first transit counts in the pulmonary artery and myocardial counts from SPECT images. Coronary endothelial function was expressed as the ratio of the CPT to rest MBF. RESULTS: Six KD patients without coronary artery lesions served as controls and ten with coronary artery aneurysms during the acute phase of the disease were separated into two groups: group 1 (n=4) with regressed and group 2 (n=6) with persistent aneurysm at follow-up. The estimated coronary endothelial function was higher in controls compared to patients with coronary artery aneurysms (2.5±0.3 vs 1.7±0.7, p<0.05). A significant difference in coronary endothelial function among groups was found (F=5.21, p<0.02). Coronary endothelial function was higher in patients of group 1 than in those of group 2 (1.9±0.6 vs 1.4±0.7, p<0.02). CONCLUSION: SPECT may be applied as a noninvasive method for assessing coronary vascular function in children with a history of KD, demonstrating an impaired response to the CPT, an endothelial-dependent vasodilator stimulus. These findings reinforce the concept that coronary endothelial dysfunction may represent a long-term sequela of KD.
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Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/metabolismo , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/fisiopatología , Endotelio Vascular/fisiopatología , Síndrome Mucocutáneo Linfonodular/fisiopatología , Tomografía Computarizada de Emisión de Fotón Único/métodos , Niño , Preescolar , Enfermedad de la Arteria Coronaria/etiología , Circulación Coronaria , Endotelio Vascular/diagnóstico por imagen , Estudios de Factibilidad , Femenino , Humanos , Lactante , Masculino , Síndrome Mucocutáneo Linfonodular/complicaciones , Síndrome Mucocutáneo Linfonodular/diagnóstico por imagen , Radiofármacos/farmacocinética , Tecnecio Tc 99m Sestamibi/farmacocinéticaRESUMEN
OBJECTIVE: Construction of prognostically relevant endpoints for clinical trials in hypertension has increasingly included coronary revascularization with myocardial infarction (MI) as manifestations of coronary artery disease. However, whether coronary revascularization and MI predict other cardiovascular events similarly is unknown. METHODS: We examined risks of cardiovascular death, all-cause death, and stroke following MI or coronary revascularization in hypertensive patients with left ventricular hypertrophy (LVH) enrolled in the Losartan Intervention For Endpoint reduction in hypertension study (LIFE). We studied 9113 patients after excluding those who died within 7 days after MI or underwent coronary revascularization within 24 h after MI. RESULTS: In multivariate Cox regression adjusting for participating countries, time-varying systolic blood pressure, and Framingham risk score, hazard ratios for cardiovascular death, all-cause death, and stroke were, respectively, 4.5 (P<0.0001), 2.9 (P<0.0001), and 1.9 (P=0.003) in 321 patients with MI as first event. In similar models, coronary revascularization as first event (n=202) was not associated with increased risks of cardiovascular death, all-cause death, and stroke (P=0.06-0.86). CONCLUSION: During follow-up of hypertensive patients with LVH, occurrence of MI but not coronary revascularization as first cardiovascular event significantly increased risk of subsequent cardiovascular death, all-cause death, and stroke. In view of differences in prognostic implications, when the goal is to have a prognostically relevant composite endpoint for trials in hypertensive patients, caution should be used in combining coronary revascularization with MI.
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Angioplastia Coronaria con Balón , Bloqueadores del Receptor Tipo 1 de Angiotensina II/uso terapéutico , Antihipertensivos/uso terapéutico , Hipertensión/tratamiento farmacológico , Losartán/uso terapéutico , Infarto del Miocardio/complicaciones , Anciano , Anciano de 80 o más Años , Humanos , Persona de Mediana Edad , Análisis Multivariante , Infarto del Miocardio/cirugía , PronósticoRESUMEN
BACKGROUND: In renal transplant recipients (RTR) an increased risk to develop cardiovascular injury is present. Transthoracic Doppler echocardiographic assessment of coronary flow velocity reserve (CFVR), a sensitive and minimally invasive technique, was recently employed to detect both macrovascular and microvascular coronary artery disease (CAD) in different clinical settings. The prevalence of coronary involvement in young adult RTR is still unknown. The aim of the study was to investigate the presence of early cardiovascular damage in asymptomatic young adult RTR. METHODS: Transthoracic Doppler echocardiographic-derived CFVR and common carotid intima-media thickness (IMT) were assessed in 25 asymptomatic young adult RTR (mean age 25.7+/-7.0 years; range 17.3-43.9) without CAD and 25 healthy controls. RESULTS: CFVR was lower in young adult RTR compared to controls (2.8+/-0.6 vs. 3.5+/-0.8; P<0.001), meanwhile left ventricular wall motion and common carotid IMT were comparable in both groups. We found a negative correlation between CFVR and age (r=-0.50; P=0.018) and months on dialysis (r=-0.54; P<0.01). CONCLUSIONS: Young adult RTR showed a reduced CFVR reflecting an impaired coronary microcirculation, which is significantly related to the age and duration of dialysis; coronary microvascular damage is detectable in the absence of changes in common carotid IMT. Non-invasive evaluation of CFVR by transthoracic stress echocardiography could be a reliable method for identification of early coronary microvascular involvement in young adult RTR.
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Enfermedades Cardiovasculares/diagnóstico por imagen , Circulación Coronaria , Vasos Coronarios/diagnóstico por imagen , Ecocardiografía Doppler , Ecocardiografía de Estrés , Trasplante de Riñón/efectos adversos , Microcirculación , Adolescente , Adulto , Factores de Edad , Velocidad del Flujo Sanguíneo , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/fisiopatología , Arterias Carótidas/diagnóstico por imagen , Estudios de Casos y Controles , Vasos Coronarios/fisiopatología , Femenino , Humanos , Masculino , Análisis Multivariante , Contracción Miocárdica , Valor Predictivo de las Pruebas , Diálisis Renal/efectos adversos , Reproducibilidad de los Resultados , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Túnica Íntima/diagnóstico por imagen , Túnica Media/diagnóstico por imagen , Función Ventricular Izquierda , Adulto JovenRESUMEN
OBJECTIVES: Left ventricular systolic wall motion abnormalities have prognostic value. Whether wall motion detected by serial echocardiographic examinations predicts prognosis in hypertensive patients with left ventricular hypertrophy (LVH) without clinically recognized atherosclerotic disease has, however, never been investigated. We examined whether 'in-treatment' wall motion abnormalities predicted outcome in the Losartan Intervention For Endpoint (LIFE) reduction in hypertension echocardiographic substudy. METHODS: We studied 749 patients without coronary artery disease, myocardial infarction (MI), or stroke history. Echocardiographic segmental wall motion abnormalities at baseline and annual re-evaluations ('as time-varying covariate') were examined in relation to endpoints (cardiovascular mortality, MI, stroke, and hospitalized heart failure). Adjusted Cox regression was used to analyze the primary composite endpoint of cardiovascular death, MI, or stroke and, separately, for fatal and nonfatal MI and hospitalized heart failure. RESULTS: During a mean follow-up of 4.8 years, an event was recorded in 67 (9%) patients. In Cox models after adjusting for age, gender, treatment, blood pressure lowering, and serial change of left ventricular mass index, 'in-treatment' segmental wall motion abnormalities were associated with subsequent composite endpoint [hazard ratio = 2.1, 95% confidence interval (CI) 1.1-3.8; P = 0.019] and MI [hazard ratio = 3.7 (1.5-8.9); P = 0.004]. CONCLUSION: In hypertensive patients with LVH and no history of cardiovascular disease, 'in-treatment' left ventricular wall motion abnormalities are associated with increased likelihood of subsequent cardiovascular events independent of age, gender, blood pressure lowering, treatment modality, and in-treatment left ventricular mass index.
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Antihipertensivos/uso terapéutico , Hipertensión/tratamiento farmacológico , Hipertensión/mortalidad , Hipertrofia Ventricular Izquierda/diagnóstico por imagen , Hipertrofia Ventricular Izquierda/mortalidad , Losartán/uso terapéutico , Anciano , Anciano de 80 o más Años , Ecocardiografía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Modelos de Riesgos Proporcionales , Factores de Riesgo , Resultado del TratamientoRESUMEN
BACKGROUND: Left-ventricular hypertrophy (LVH) is a recognized risk factor for myocardial infarction (MI). However, detection of MI by standard electrocardiographic (ECG) criteria may be hampered in patients with LVH. In this setting of hypertensive LVH, the accuracy of two-dimensional (2D) echocardiography in detecting incident MI is unknown. Thus, we compared the accuracy of 2D echocardiography with Minnesota-code ECG criteria in detecting incident MI, adjudicated during serial evaluation in patients with hypertension and LVH. METHODS: In the ECG substudy of the Losartan Intervention for Endpoint Reduction in Hypertension (LIFE) Study, complete baseline wall-motion (WM) evaluation was obtained in 904 hypertensive patients with ECG LVH who did not have a left-bundle branch block. Electrocardiography and echocardiograms obtained at annual follow-up visits were evaluated for ECG Q-waves by Minnesota codes and WM abnormalities, respectively (mean follow-up, 4.8+/-0.9 SD years). Occurrence of incident clinical MI during follow-up was adjudicated by an expert end-point committee. RESULTS: In two logistic models adjusting for confounders, incident MI was independently associated with either incident Q-waves by the Minnesota code (odds ratio [OR], 6.1; 95% confidence interval [CI], 2.4-15.3) or incident and worsened WM abnormalities (OR, 11.9; 95% CI, 4.5-32.0), and the association was stronger for WM abnormalities than for Q-waves (P < .0001). Detection of incident MI by ECG or 2D echocardiography was obtained with sensitivities of 29% and 68% and specificities of 95% and 84%, respectively. CONCLUSIONS: Wall-motion abnormalities on serial 2D ECGs recognize incident MI better than do Minnesota-code ECG criteria during follow-up of patients with hypertension and LVH.
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Hipertensión/complicaciones , Hipertrofia Ventricular Izquierda/complicaciones , Infarto del Miocardio/diagnóstico , Anciano , Anciano de 80 o más Años , Ecocardiografía , Electrocardiografía , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico por imagenRESUMEN
BACKGROUND: Left ventricular wall motion (WM) abnormalities have recognized prognostic significance in patients with coronary or other heart diseases; however, whether abnormal WM predicts adverse events in adults without overt cardiovascular disease has not been assessed. Our objective was to determine whether echocardiographic WM abnormalities predict subsequent cardiovascular events in a population-based sample. METHODS AND RESULTS: Participants (n=2864, mean age 60+/-8 years, 64% women) without clinically evident cardiovascular disease in the second Strong Heart Study examination who had complete echocardiographic WM assessment were studied. Echocardiographic assessment revealed that 5% of participants (n=140) had focal hypokinesia, and 1.5% (n=42) had WM abnormalities. Relationships between WM abnormalities and fatal and nonfatal cardiovascular events (including myocardial infarction, stroke, coronary artery disease, and heart failure; n=554) and cardiovascular death (n=182) during 8+/-2 years follow-up were examined. In Cox regression, after adjustment for age, gender, waist/hip ratio, systolic blood pressure, and diabetes mellitus, segmental WM abnormalities were associated with a 2.5-fold higher risk of cardiovascular events and a 2.6-fold higher risk of cardiovascular death (both P<0.0001). In similar multivariable models, global WM abnormalities were associated with a 2.4-fold higher risk of cardiovascular events (P=0.001) and a 3.4-fold higher risk of cardiovascular death (P=0.003). CONCLUSIONS: Echocardiographic left ventricular WM abnormalities in adults without overt cardiovascular disease are associated with 2.4- to 3.4-fold higher risks of cardiovascular morbidity and mortality, independent of established risk factors.
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Ventrículos Cardíacos/fisiopatología , Disfunción Ventricular/epidemiología , Anciano , Angina de Pecho/epidemiología , Enfermedades Cardiovasculares/epidemiología , Estudios de Cohortes , Ecocardiografía , Femenino , Humanos , Indígenas Norteamericanos/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/epidemiología , Prevalencia , Pronóstico , Factores de Riesgo , Estados Unidos/epidemiologíaRESUMEN
BACKGROUND: Coronary flow reserve (CFR) may be reduced both in arterial hypertension and in hypercholesterolemia. The aim of the study was to assess an association between CFR and levels of plasma total cholesterol (TC) in untreated arterial hypertension. METHODS: We studied 54 consecutive, untreated hypertensive outpatients free of coronary heart disease. Twenty of them had normal TC and 34 high TC (>/=200 mg/dL). Standard echocardiograms and transthoracic Doppler interrogation of the distal left anterior descending artery were obtained. Coronary diastolic peak velocities were measured both at rest and after low-dose dipyridamole. The CFR was calculated as dipyridamole/resting velocities ratio. RESULTS: The two groups had similar age, body mass index, heart rate, and diastolic blood pressure (BP). Patients with high TC had higher systolic BP (P < .05), triglycerides (P < .02), LDL-cholesterol, and TC/HDL-cholesterol ratio (both P < .0001) than controls. Left ventricular (LV) mass index, relative wall thickness, and fractional shortening did not differ between the two groups. Coronary diastolic peak velocities were similar at rest but lower after dipyridamole in patients with high TC (P < .02). As a consequence, CFR was reduced (P < .002). In multiple linear regression analyses, adjusting for age, heart rate, systolic BP, smoking, and relative wall thickness, TC (beta = -0.338) or high LDL-cholesterol (beta = -0.301) (both P < .001) were predictors of lower CFR independently of the concomitant effect of potential confounders. CONCLUSIONS: In hypertensive patients free of coronary artery disease, the degree of impairment in coronary vasodilator capacity is independently associated with plasma cholesterol and LDL-cholesterol.
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LDL-Colesterol/sangre , Colesterol/sangre , Circulación Coronaria , Vasos Coronarios/fisiopatología , Hipercolesterolemia/diagnóstico , Hipertensión/diagnóstico , Enfermedad Coronaria , Femenino , Humanos , Hipercolesterolemia/complicaciones , Hipercolesterolemia/fisiopatología , Hipertensión/complicaciones , Hipertensión/fisiopatología , Masculino , Persona de Mediana EdadRESUMEN
BACKGROUND: Transthoracic Doppler echocardiography of internal mammary artery grafts (MAGs) has been tested by the supraclavicular approach, but little information is available about the parasternal approach. OBJECTIVE: To evaluate the usefulness of parasternal transthoracic Doppler echocardiography to assess the patency of left and right MAGs. PATIENTS AND METHODS: Forty-eight patients with previous MAGs were divided into two groups on the basis of coronary angiography: 42 patients had patent MAGs and six patients had severe MAG stenosis. Doppler echocardiography of MAGs was performed on all patients, both at baseline and after low-dose dipyridamole infusion. Systolic and diastolic time-velocity integrals and their ratios were obtained, and MAG flow reserve was calculated. RESULTS: Patients with patent MAGs had a predominant diastolic flow, while a prominent systolic pattern was found in the presence of MAG stenosis. In patients with stenosis, baseline Doppler analysis showed a lower diastolic peak velocity (DPV) (P<0.01), diastolic time-velocity integral (P<0.05), and diastolic and systolic time-velocity integral ratios (both P<0.005), and a reduced MAG flow reserve (P<0.001). In the overall population, when adjusting for clinical variables, a multilinear regression analyis underscored MAG flow reserve (beta=0.38, P<0.01) and baseline DPV (beta=0.29, P<0.05) as independent determinants of MAG stenosis (cumulative R2=0.25, P<0.005). CONCLUSIONS: Doppler echocardiographic evaluation of MAGs is a reliable, noninvasive tool to assess MAG patency and functional status of the vessel. MAG blood flow reserve and baseline DPV are independent determinants of MAG stenosis.
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Puente de Arteria Coronaria/métodos , Enfermedad Coronaria/diagnóstico por imagen , Enfermedad Coronaria/cirugía , Ecocardiografía Transesofágica , Anciano , Estudios de Cohortes , Puente de Arteria Coronaria/efectos adversos , Ecocardiografía Doppler en Color , Femenino , Rechazo de Injerto , Supervivencia de Injerto , Humanos , Anastomosis Interna Mamario-Coronaria , Modelos Lineales , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico/métodos , Complicaciones Posoperatorias/diagnóstico por imagen , Probabilidad , Pronóstico , Medición de Riesgo , Sensibilidad y Especificidad , Estadísticas no Paramétricas , Grado de Desobstrucción VascularRESUMEN
After percutaneous transluminal coronary angioplasty (PTCA), stress-echocardiography and gated single photon emission computerized tomography (g-SPECT) are usually performed but both tools have technical limitations. The present study evaluated results of PTCA of left anterior descending artery (LAD) six months after PTCA, by combining transthoracic Doppler coronary flow reserve (CFR) and color Tissue Doppler (C-TD) dobutamine stress. Six months after PTCA of LAD, 24 men, free of angiographic evidence of restenosis, underwent standard Doppler-echocardiography, transthoracic CFR of distal LAD (hyperemic to basal diastolic coronary flow ratio) and C-TD at rest and during dobutamine stress to quantify myocardial systolic (Sm) and diastolic (Em and Am, Em/Am ratio) peak velocities in middle posterior septum. Patients with myocardial infarction, coronary stenosis of non-LAD territory and heart failure were excluded. According to dipyridamole g-SPECT, 13 patients had normal perfusion and 11 with perfusion defects. The 2 groups were comparable for age, wall motion score index (WMSI) and C-TD at rest. However, patients with perfusion defects had lower CFR (2.11 +/- 0.4 versus 2.87 +/- 0.6, p < 0.002) and septal Sm at high-dose dobutamine (p < 0.01), with higher WMSI (p < 0.05) and stress-echo positivity of LAD territory in 5/11 patients. In the overall population, CFR was related negatively to high-dobutamine WMSI (r = -0.50, p < 0.01) and positively to high-dobutamine Sm of middle septum (r = 0.55, p < 0.005). In conclusion, even in absence of epicardial coronary restenosis, stress perfusion imaging reflects a physiologic impairment in coronary microcirculation function whose magnitude is associated with the degree of regional functional impairment detectable by C-TD.
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Angioplastia Coronaria con Balón/métodos , Estenosis Coronaria/diagnóstico por imagen , Estenosis Coronaria/cirugía , Dobutamina , Ecocardiografía/métodos , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/cirugía , Circulación Coronaria , Estenosis Coronaria/complicaciones , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/cirugía , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Resultado del Tratamiento , Vasodilatadores , Disfunción Ventricular Izquierda/etiologíaRESUMEN
OBJECTIVE: To examine the effects of nebivolol, a beta-blocker with nitroxide-mediated vasodilating properties, on coronary flow reserve (CFR) in patients with uncomplicated arterial hypertension. DESIGN, SETTING AND PATIENTS: Fourteen newly diagnosed, never-treated, World Health Organization grade I-II hypertensive patients (male/female, 10/4; mean age, 47 years), free of coronary heart disease, underwent standard Doppler echocardiography and determination of CFR in the distal left anterior descending artery by low-dose dipyridamole (0.56 mg/kg intravenously in 4 min) at baseline and after 4 weeks of treatment with 5 mg nebivolol once daily. RESULTS: At baseline, nine patients had left ventricular (LV) hypertrophy (LV mass index > or = 51 g/m). After 4 weeks of therapy, the blood pressure was decreased from 148 +/- 8.1/101.4 +/- 4.6 mmHg to 140.7 +/- 7.0/91.1 +/- 7.4 mmHg and end-systolic stress was also significantly reduced. Heart rate was reduced (P <0.01), whereas LV end-diastolic diameter and stroke volume tended to increase (P=0.07 and P=0.09, respectively). No changes were detected in the LV mass index, relative wall thickness, fractional shortening and LV diastolic properties. Both resting and dipyridamole rate-pressure products were lower after nebivolol but dipyridamole-induced changes were not influenced by the therapy. In contrast, nebivolol therapy did not alter coronary velocities at rest, but caused a greater increase in coronary velocities after dipyridamole (P <0.03), leading to a greater CFR (2.12 +/- 0.33 versus 1.89 +/- 0.31, P <0.0001). Nebivolol induced an absolute increase of 8% in the CFR in nine of 14 patients (64.3%). CONCLUSIONS: In hypertensive patients free of coronary artery disease, 4-week nebivolol therapy induces a significant increase of the CFR. Nebivolol preserves coronary flow at rest despite the reduction of metabolic (O2 consumption) and hemodynamic (diastolic blood pressure) determinants. The increase of hyperemic coronary velocities appears due to the reduction of coronary resistance.
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Antihipertensivos/administración & dosificación , Benzopiranos/administración & dosificación , Circulación Coronaria/efectos de los fármacos , Etanolaminas/administración & dosificación , Hipertensión/tratamiento farmacológico , Enfermedad Coronaria/diagnóstico por imagen , Ecocardiografía , Femenino , Humanos , Hipertensión/diagnóstico por imagen , Masculino , Persona de Mediana Edad , NebivololRESUMEN
BACKGROUND: The aim of this study was to assess the role of tissue Doppler (TD) in the identification of left ventricular (LV) myocardial regionl abnormalities in overt hypothyroidism. METHODS: Fourteen women with newly diagnosed, never treated overt hypothyroidism and 14 healthy women, matched for age, underwent standard echocardiography and pulsed TD, by placing the sample volume at the basal posterior septum and lateral mitral annulus, in the apical 4-chamber view. The myocardial systolic (SM) and diastolic velocities (Em, Am and their ratio) and time intervals (relaxation time [RTm], pre-contraction time [PCTm], contraction time) were measured. RESULTS: The two groups were comparable for body surface area, blood pressure and heart rate. At standard echocardiography, patients with overt hypothyroidism had a significantly greater septal thickness and LV mass index, a longer LV pre-ejection period (PEP), deceleration time and isovolumic relaxation time (IVRT) and a lower E peak velocity and E/A ratio. TD showed a significantly longer PCTm and RTm and a lower Em and Em/Am ratio of both the septum and mitral annulus in overt hypothyroidism. The ratio of the standard Doppler E to Em of the mitral annulus was 5.5 +/- 1.2 in controls and 5.3 +/- 1.7 in overt hypothyroidism (p = NS). In the overall population, PEP, IVRT, PCTm and RTm were correlated negatively with FT3 and FT4, and positively with thyroid-stimulating hormone. After adjusting for age, body surface area and heart rate in separate multivariate analyses, the associations of TD PCTm with the thyroid hormones and thyroid-stimulating hormone were greater than the homologous associations of standard Doppler PEP. CONCLUSIONS: Standard echocardiography confirms itself as a satisfactory diagnostic technique for the identification of LV global dysfunction in overt hypothyroidism. Pulsed TD may be useful to determine the severity of LV myocardial dysfunction in relation to the degree of hormonal impairment.
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Ecocardiografía Doppler de Pulso , Hipotiroidismo/diagnóstico por imagen , Hipotiroidismo/fisiopatología , Función Ventricular Izquierda , Adulto , Presión Sanguínea , Superficie Corporal , Femenino , Frecuencia Cardíaca , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/fisiopatología , Humanos , Hipotiroidismo/sangre , Persona de Mediana Edad , Reproducibilidad de los Resultados , Tirotropina/sangre , Tiroxina/sangre , Triyodotironina/sangreRESUMEN
BACKGROUND: An asynchronous contraction occurring during a prolonged relaxation period, defined as post-systolic motion (PSM), has been described as being a consequence of coronary occlusion but also in other conditions including isolated left bundle branch block (LBBB). The aim of this study was to characterize PSM of the interventricular septum at pulsed tissue Doppler in LBBB with or without stenosis of the left anterior descending coronary artery (LAD). METHODS: Forty-two patients with chronic, complete LBBB and tissue Doppler-derived septal PSM were divided into two groups on the basis of their coronary angiography: 27 without LAD stenosis and 15 with LAD stenosis (> or = 50%). Standard Doppler echocardiography and tissue Doppler of both the middle posterior septum and lateral mitral annulus were performed in the apical 4-chamber view. RESULTS: Standard Doppler diastolic indexes were comparable between the two groups. Septal tissue Doppler showed lower myocardial systolic (Sm) and atrial peak velocities (both p < 0.05), a higher PSM (p < 0.005), and a longer relaxation time (p < 0.02) and pre-contraction time (p < 0.05) in patients with LAD stenosis. A Sm/PSM ratio < 1 was detected in 86% of patients with LAD stenosis and in 22% without LAD stenosis (sensitivity 73%, specificity 77%, positive predictive value 64%, negative predictive value 84%). Tissue Doppler of the mitral annulus showed a significantly longer relaxation time and pre-contraction time and a lower atrial velocity in the presence of LAD stenosis. In the overall population, PSM was positively associated with ejection fraction and negatively with age and septal thickness. In a multiple linear regression analysis, only LAD stenosis (beta = 0.42, p < 0.005) and ejection fraction (beta = 032, p = 0.03) were independent predictors of PSM (cumulative r2 = 0.27, p < 0.002). CONCLUSIONS: Tissue Doppler may be useful to distinguish septal myocardial asynchrony in LBBB with and without LAD stenosis.
Asunto(s)
Bloqueo de Rama/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Ecocardiografía Doppler de Pulso/métodos , Adulto , Anciano , Análisis de Varianza , Bloqueo de Rama/complicaciones , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/complicaciones , Técnicas de Diagnóstico Cardiovascular , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Contracción Miocárdica/fisiología , Probabilidad , Estudios Prospectivos , Medición de Riesgo , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , Función Ventricular Izquierda/fisiologíaRESUMEN
OBJECTIVE: To assess the association between coronary flow reserve (CFR) and levels of left ventricular mass (LVM) exceeding the compensatory needs in arterial hypertension. DESIGN, SETTINGS AND PATIENTS: The association between the excess of LV mass and CFR was assessed in a population of 40 consecutive hypertensive outpatients free of coronary heart disease, 22 with appropriate and 17 with inappropriately high LVM (i.e. LVM exceeding 128% of the value predicted by sex, stroke work and height in m(2.7)). The CFR (the ratio between dipyridamole and basal diastolic peak velocity) of the distal left anterior descending artery was measured by transthoracic Doppler echocardiography. RESULTS: Patients with inappropriate LVM had similar age, body mass index (BMI), baseline blood pressure (BP) and coronary velocities, but lower LV systolic function, post-dipyridamole diastolic peak velocities (P < 0.05) and lower CFR (P < 0.002) than patients with appropriate LVM. CFR was negatively related to the extent of the excess of LVM (beta = -0.44, P < 0.005), independently of potential combined effect of age, BMI and post-dipyridamole diastolic BP. Impairment of CFR (i.e. < 2) was better discriminated by identification of clear-cut inappropriate LVM (P < 0.004) than by the presence of LV hypertrophy (i.e. LV mass index > or = 51 g/m(2.7); P = 0.057). CONCLUSIONS: In hypertensive patients free of coronary artery disease, the degree of reduction in CFR is associated with the excess of LVM beyond the values compensatory for individual haemodynamic load. This relation is also independent of the presence of LV hypertrophy.
Asunto(s)
Circulación Coronaria , Hipertensión/complicaciones , Hipertensión/fisiopatología , Hipertrofia Ventricular Izquierda/etiología , Adaptación Fisiológica , Adulto , Ecocardiografía , Ecocardiografía Doppler , Femenino , Hemodinámica , Humanos , Hipertrofia Ventricular Izquierda/diagnóstico por imagen , Masculino , Persona de Mediana EdadRESUMEN
BACKGROUND: The aim of this study was to evaluate the patency of left and right internal mammary artery grafts respectively on the left anterior descending and right coronary artery by noninvasive transthoracic color Doppler echocardiography. METHODS: Thirty eight patients (34 males, 4 females, mean age 59 +/- 2 years), with a history of coronary artery bypass grafting for a total of 42 mammary artery grafts, were studied by means of color Doppler echocardiography at baseline and after vasodilation with dipyridamole infusion (0.56 mg/kg i.v. over 4 min). The evaluated echocardiographic parameters included: systolic (SPV) and diastolic peak velocities (DPV), systolic (SVI) and diastolic velocity-time integrals (DVI), and the DPV/SPV and DVI/SVI ratios. We also calculated the dipyridamole infusion to baseline ratio of the diastolic peak velocities (DPVdip/DPVbaseline), the index of internal mammary artery graft blood flow reserve and the percent DPV increment as an index of graft stenosis. RESULTS: On the basis of coronary angiography, two groups were selected: group A (36 mammary grafts) with patent grafts and group B (6 mammary grafts) with moderate or severe stenosis of the grafts. Group A had a predominant diastolic pattern with a DPV of 0.24 +/- 0.13 m/s, whereas group B had a predominant systolic pattern with a reduced DPV of 0.12 +/- 0.03 m/s (p < 0.01). Dipyridamole induced an increase in the DPV respectively of 86.8 +/- 64.4% in group A and 13.8 +/- 15.9% in group B (p < 0.001). Statistical analysis (Mann-Whitney test) revealed a significant difference between the two groups for the baseline DPV (p < 0.01), DVI (p < 0.05), DPV/SPV ratio (p < 0.005), DVI/SVI ratio (p < 0.05), and for the after dipyridamole infusion values: DPV (p < 0.0001), DVI (p < 0.005), DPV/SPV ratio (p < 0.001), and DVI/SVI ratio (p < 0.05). Multivariate analysis showed that the percent DPV increment, the DPVdip/DPVbaseline ratio and the baseline DPV were independent determinants of the stenosis as evaluated at angiography (beta = -0.38, p < 0.01; beta = -0.37, p < 0.01, and beta = -0.33, p < 0.05, respectively; cumulative r2 = 0.25, standard error 0.30 m/s, p < 0.005). CONCLUSIONS: The echocardiographic evaluation of the mammary grafts is a simple, noninvasive method for the assessment of the graft patency and of the functional status of the vessel. The percent DPV increment and baseline DPV were independent determinants of mammary graft stenosis.
Asunto(s)
Puente de Arteria Coronaria , Ecocardiografía , Arterias Mamarias/diagnóstico por imagen , Arterias Mamarias/cirugía , Grado de Desobstrucción Vascular/fisiología , Velocidad del Flujo Sanguíneo/efectos de los fármacos , Velocidad del Flujo Sanguíneo/fisiología , Angiografía Coronaria , Diástole/efectos de los fármacos , Diástole/fisiología , Dipiridamol/uso terapéutico , Ecocardiografía Doppler en Color , Femenino , Oclusión de Injerto Vascular/diagnóstico , Oclusión de Injerto Vascular/fisiopatología , Humanos , Infusiones Intraarteriales , Masculino , Persona de Mediana Edad , Análisis Multivariante , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad , Estadística como Asunto , Sístole/efectos de los fármacos , Sístole/fisiología , Resultado del Tratamiento , Grado de Desobstrucción Vascular/efectos de los fármacos , Vasodilatadores/uso terapéuticoRESUMEN
The assessment of coronary flow reserve with transthoracic Doppler echocardiography, measured as the ratio between hyperemic and baseline coronary flow velocities, is a new tool for the evaluation of coronary artery disease and coronary microcirculation. Color-guided pulsed Doppler allows almost optimal identification of flow velocities at the middle and distal left anterior descending artery and good visualization of the right coronary artery. The development of ultrasound technology (second harmonic, contrast agents, dedicated softwares) is responsible for great feasibility (until 98% for the left anterior descending artery and 40-50% for the right coronary artery) and very good reproducibility of this tool. Doppler-derived coronary flow reserve has excellent concordance with that obtainable with intravascular Doppler flow wire. Diagnosis of stenosis and restenosis after stent implantation in the middle and/or proximal left anterior descending artery and of stenosis of the right coronary artery is very accurate. In the absence of stenosis of epicardial coronary arteries, the reduction in coronary flow reserve implies a damage of coronary microcirculation, which can be a determinant of angina pectoris and signs of myocardial ischemia in arterial hypertension, diabetes mellitus and coronary X syndrome. Further progress may be expected by using myocardial contrast agents for quantitation of regional myocardial coronary flow reserve.
Asunto(s)
Circulación Coronaria , Enfermedad Coronaria/diagnóstico por imagen , Enfermedad Coronaria/fisiopatología , Ecocardiografía Doppler , Velocidad del Flujo Sanguíneo , Factores de Confusión Epidemiológicos , Estenosis Coronaria/diagnóstico por imagen , Estenosis Coronaria/fisiopatología , Humanos , Microcirculación , Reproducibilidad de los Resultados , Proyectos de Investigación , Ultrasonografía IntervencionalRESUMEN
The aim of this study was to assess the relation between coronary blood flow and left ventricular (LV) myocardial diastolic dysfunction in arterial hypertension. The study population included 30 hypertensive patients who were free of coronary artery disease and pharmacologic therapies. They underwent standard Doppler echocardiography and color tissue Doppler of the middle posterior septum at baseline and with high-dose dobutamine, and second-harmonic Doppler flow analysis of the distal left anterior descending coronary artery at baseline and after vasodilation by dipyridamole (0.56 mg/kg IV in 4'). Coronary flow reserve (CFR) was estimated as the ratio of hyperemic and baseline diastolic flow velocities. According to CFR, hypertensives were divided into 2 groups: 15 patients with normal CFR (>/=2) and 15 patients with reduced CFR (<2). The 2 groups were comparable for sex, age, body mass index, baseline heart rate, and blood pressure. LV mass index was greater in hypertensives with reduced CFR (p <0.01). By color tissue Doppler, baseline and high-dose dobutamine septal systolic velocities did not differ between the 2 groups. The ratio between myocardial velocities in early diastole and at atrial contraction (E(m)/A(m) ratio) was lower in patients with reduced CFR, both at baseline (p <0.05) and with high-dose dobutamine (p <0.00001). After adjusting for age, body mass index, LV mass index, and both high-dose dobutamine diastolic blood rate and heart rate by a multiple linear regression analysis, E(m)/A(m) ratio at high-dose dobutamine was independently associated with CFR in the overall population (beta 0.62, p <0.0005) (cumulative R(2) 0.38, p <0.0005). In conclusion, this study provides evidence of an independent association between CFR and myocardial diastolic function. In hypertensive patients without coronary artery stenosis, CFR alteration may be a determinant of myocardial diastolic dysfunction or diastolic impairment that should be taken into account as possibly contributing to coronary flow reduction.
Asunto(s)
Circulación Coronaria/fisiología , Diástole/fisiología , Ecocardiografía Doppler , Hipertensión/diagnóstico por imagen , Contracción Miocárdica/fisiología , Disfunción Ventricular Izquierda/diagnóstico por imagen , Adulto , Velocidad del Flujo Sanguíneo/fisiología , Volumen Cardíaco/fisiología , Relación Dosis-Respuesta a Droga , Ecocardiografía Doppler en Color , Ecocardiografía de Estrés , Femenino , Humanos , Hipertensión/fisiopatología , Hipertrofia Ventricular Izquierda/diagnóstico por imagen , Hipertrofia Ventricular Izquierda/fisiopatología , Masculino , Persona de Mediana Edad , Valores de Referencia , Flujo Sanguíneo Regional/fisiología , Disfunción Ventricular Izquierda/fisiopatologíaRESUMEN
BACKGROUND: The reduction of coronary flow reserve (CFR) found in arterial hypertension may be due to changes in afterload, left ventricular (LV) structure, and metabolic factors. Also, insulin-like growth factor-1 (IGF-1) may be associated with the magnitude of CFR in relation to its modulating action on cardiac and endothelial function. METHODS: A total of 44 newly diagnosed, untreated hypertensive patients, who were free of diabetes mellitus and coronary artery disease, underwent M-mode analysis, second-harmonic Doppler echocardiographic assessment of CFR (dipyridamole infusion 0.56 mg/kg intravenously in four patients), determination of circulating free IGF-1, and insulin resistance. Based on CFR levels, hypertensive subjects were divided into two groups: 18 with normal CFR (> or = 2) and 26 with impaired CFR (<2). RESULTS: Patients with normal CFR had lower diastolic blood pressure, heart rate, and LV mass index but higher free circulating IGF-I than patients with reduced CFR (P < .001). Insulin resistance was not significantly different between the two groups. In a first multilinear regression analysis that included demographic and echocardiographic variables, insulin resistance was independently associated with CFR (standardized beta coefficient = -0.31, P < .05) in the overall population. However, in a subsequent model which included also IGF-1, the relationship between insulin resistance and CFR disappeared, whereas IGF-1 was the main independent determinant of CFR (beta = 0.51, P < .0002). CONCLUSIONS: Free IGF-1 circulating levels are independently associated with CFR in hypertensive individuals free of overt coronary artery disease. A possible beneficial effect exerted by IGF-1 on coronary blood flow may be supposed in arterial hypertension.