RESUMEN
Comparison of velocity parameters of blood flow and absolute coronary reserve (absCR) in the left anterior descending and posterior interventricular coronary arteries (ADCA and PICA) with calculation of relative coronary reserve (relCR) and determination of its normative values was carried out with the help of transthoracic echocardiography in 29 healthy volunteers (mean age 40+/-13 years). Assessment of the role of absCR and relCR in ADCA in diagnostics of hemodynamically significant stenoses of this vessel was performed in 88 patients with syndrome of cardiac pain (mean age 40+/-12 years). Coronary angiography was used as a reference method. Coronary blood flow in distal segments of ADCA and PICA was measured at baseline and during infusion of a vasodilator (dipyridamole up to 0.84 mg/kg as intravenous infusion). AbsCR for each of these arteries was determined as ratio of hyperemic peak diastolic blood flow velocity and its baseline value. Lowering of absCR was diagnosed at its level <2.0). RelCR was calculated only for ADCA as ratio of absCR of ADCA and PICA. It was established that parameters of coronary blood flow and absCR level in healthy volunteers in ADA and PICA had no significant differences. Therefore these vessels were considered referent for each other. In the norm relCR in ADA was 1.09+/-0.36 (95% confidence interval from 0.95 to 1.23). We proved that ADA abs CR in <2.0 served as predictor of ADA stenosis >50% with sensitivity 89% and specificity 85%. However 22% of subjects with lowering of absCR had ADA stenoses <50%, microvascular involvement, or belonged to the group of healthy volunteers. It was established that ADA relCR <0.80 in patients with ADA absCR <2.0 was a sensitive and specific sign of isolated ADA stenosis >50%.
Asunto(s)
Estenosis Coronaria , Vasos Coronarios , Dipiridamol , Ecocardiografía Doppler/métodos , Reserva del Flujo Fraccional Miocárdico/efectos de los fármacos , Adulto , Velocidad del Flujo Sanguíneo/efectos de los fármacos , Constricción Patológica/diagnóstico , Estenosis Coronaria/diagnóstico , Estenosis Coronaria/fisiopatología , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , VasodilatadoresRESUMEN
Analysis of possibilities of transthoracic echocardiography (TTEchoCG) diagnosis of hemodynamically significant stenoses of anterior descending and right coronary arteries (ADCA and RCA) based on Doppler assessment of coronary reserve (CR) was carried out in 73 patients with cardiac pain syndrome (mean age 48+/-7 years, 60 men, 13 women). As a referent method we used coronary angiography. Coronary blood flow at baseline and during administration of a vasodilator (dipyridamole up to 0.84 mg/kg) was assessed by broadband ultrasound transducer in the mode of noncontrast tissue second harmonic imaging in distal segments of ADCA and posterior interventricular artery (PIVA). CR was calculated as ratio of peak hyperemic to baseline diastolic coronary blood flow velocity. CR <2.0 was diagnosed as lowered. We found that TTEchoCG was simple noninvasive method of assessment of CR in distal thirds of ADCA and PIVA, which can be fulfilled in 90 and 86%of patients, respectively. We also revealed that hemodynamically significant stenoses of ADCA and PIVA caused CR lowering distally to zone of stenosis and that degree of CR lowering depended on severity of vascular narrowing. We found that CR<2.0 in distal third of ADCA was a predictor of its >50% narrowing with sensitivity 78%, specificity 85%, positive predictive value (PPV) 67%, and negative predictive value (NPV) 90%. In the presence of >70% ADCA stenosis sensitivity and NPV of the parameter reached 100%. We revealed that CR<2.0 in PIVA served as a marker of >50% RCA stenosis with sensitivity 88%, specificity 86%, PPV 68%, and NPV 95%. In the presence of >70% RCA stenosis sensitivity and NPV of the parameter rose up to 92 and 97%, respectively.
Asunto(s)
Estenosis Coronaria/diagnóstico por imagen , Vasos Coronarios/diagnóstico por imagen , Dipiridamol , Ecocardiografía de Estrés , Corazón/fisiopatología , Hemodinámica/efectos de los fármacos , Adulto , Velocidad del Flujo Sanguíneo/efectos de los fármacos , Angiografía Coronaria , Circulación Coronaria/efectos de los fármacos , Estenosis Coronaria/fisiopatología , Vasos Coronarios/efectos de los fármacos , Vasos Coronarios/fisiopatología , Dipiridamol/administración & dosificación , Ecocardiografía de Estrés/métodos , Ecocardiografía de Estrés/normas , Femenino , Corazón/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Índice de Severidad de la Enfermedad , Vasodilatadores/administración & dosificaciónRESUMEN
Comparative analysis of possibilities of transthoracic echocardiography (TTE) and coronary angiography in diagnosis of chronic occlusions of anterior descending (ADA), circumflex (CA), and right coronary (RA) arteries was carried out in 100 patients (90 men, 10 women, mean age 51 +/- 11 years). With the help of TTE we analyzed direction, structural and temporal parameters of coronary blood flow in zones of potential epicardial and intramyocardial collateral filling: for ADA - in distal segment (dADA) and septal branches (SBADA), for CA - in obtuse marginal branches (OMB), for RCA - in posterior interventricular artery (PIA) and septal branches (SBRCA). We found that TTE was a sensitive and highly specific method of diagnosis of ADA and RCA occlusions, but did not allow to diagnose adequately occlusions of CA. We proved that main criterion of ADA occlusion was registration of retrograde or retroanterograde collateral blood flow in dADA or SBADA. Sensitivity of detection of inverted blood flow in dADA without consideration of direction of blood flow in SBADA in diagnosis of ADA occlusions was 77%, with consideration of SBRCA - 85%, specificity - 97%. Detection of retrograde or retroanterograde blood flow in SBADA was indicative of proximal level of artery lesion with sensitivity 100% and specificity 75%. Detection of retrograde or collateral flow in PIA or SBRCA was found to be main criterion of RCA occlusion. Sensitivity of detection of inverted blood flow in PIA without taking into account direction of blood flow in SBRCA in diagnosis of RCA occlusions was 77%, with consideration of SBRCA - 88%, specificity - 98%. The study of lat flow in SBRCA did not allow to determine accurately the level of artery lesion.
Asunto(s)
Estenosis Coronaria/diagnóstico por imagen , Vasos Coronarios/diagnóstico por imagen , Ecocardiografía Doppler en Color/métodos , Velocidad del Flujo Sanguíneo , Enfermedad Crónica , Circulación Coronaria/fisiología , Estenosis Coronaria/fisiopatología , Vasos Coronarios/fisiopatología , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Índice de Severidad de la EnfermedadRESUMEN
The lecture contains: presentation of possibilities of ultrasound and tomographic methods of investigation in visualization of major coronary arteries; consideration in a comparative aspect of main advantages, disadvantages and limitations of these methods in diagnostics of coronary atherosclerosis; analysis of indications for application and perspectives of their use in everyday clinical practice in patients with a diagnosis of possible or verified ischemic heart disease.
Asunto(s)
Enfermedad de la Arteria Coronaria/diagnóstico , Vasos Coronarios/patología , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/patología , Vasos Coronarios/diagnóstico por imagen , Ecocardiografía , Ecocardiografía Transesofágica , Humanos , Angiografía por Resonancia Magnética , Tomografía Computarizada Espiral , Tomografía Computarizada por Rayos XRESUMEN
The lecture deals with methodological aspects and diagnostic potential of the use of novel ultrasound technologies -- transesophageal and transthoracic doppler ultrasonography of coronary arteries for noninvasive assessment of coronary blood flow and coronary reserve. It contains detailed description of technique of visualization of coronary arteries from transesophageal and from transthoracic approaches and interpretation of dopplero-graphic parameters of laminar and turbulent coronary flows. Diagnostic role of the use of contrast echo imaging of coronary arteries is also discussed and dopplero-graphic criteria of occlusion and hemodynamically significant coronary artery stenosis as well as characteristics of normal and lowered coronary reserve are presented.
Asunto(s)
Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Ecocardiografía Transesofágica/métodos , Ecocardiografía/métodos , HumanosRESUMEN
AIM: To elucidate the role of evaluation of coronary reserve in coronary sinus by transesophageal doppler for assessment of efficacy of various revascularization interventions. MATERIAL AND METHODS: Patients with isolated stenoses of either left anterior descending or circumflex coronary artery subjected to stenting (n=14) and with two vessel disease subjected to bypass surgery (n=20). Dipyridamole was used as a stress agent. Coronary reserve was calculated as ratio of peak hyperemic to baseline antegrade coronary sinus blood flow velocity (CR(P)) and as ratio of hyperemic to baseline antegrade coronary sinus volume blood flow (CR(VBF)). RESULTS: In patients with atherosclerotic lesions in the system of left coronary artery normalization of CR(P) after stenting of single vessel stenoses and of CR(VBF) after bypass surgery in two vessel disease were markers of efficacy of revascularization with sensitivity 75 and 71%, respectively.
Asunto(s)
Puente de Arteria Coronaria/métodos , Vasos Coronarios/diagnóstico por imagen , Ecocardiografía Transesofágica/métodos , Isquemia Miocárdica/diagnóstico por imagen , Isquemia Miocárdica/cirugía , Ultrasonografía Doppler/métodos , Vasos Coronarios/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Isquemia Miocárdica/fisiopatologíaRESUMEN
AIM: To elucidate the role of the use of impulse-wave tissue doppler technology during stress echocardiography with transesophageal atrial pacing for diagnosis and evaluation of concealed myocardial ischemia. MATERIAL: Patients (n=82, 72 men, 10 women, mean age 43+/-10 years) with syndrome of cardiac pain of obscure etiology. METHODS: Regional contractility of left ventricular wall was studied through apical approach with the use of 12-segment model. Peak systolic velocity of myocardial segments (S, cm/s), its acceleration (Asl, cm/s(2)), duration of period of preejection (PEP, ms) and isovolumic relaxation time (IVRT, ms) of each segment were calculated at rest, and during subthreshold and threshold pacing. RESULTS: Concealed myocardial ischemia was revealed by stress echo in 44 patients. Total number of analyzed segments was 984 and parameters of impulse-wave tissue doppler could be measured in 959 (97%) segments. At peak pacing rate during stress test 789 (82%) segments were normokinetic, 142 (15%) - hypokinetic, 20 (2%) - akinetic, and 8 (1%) - dyskinetic. Absence of increase or decrease of S and prolongation of PEP by 10% or more from baseline during stress test were found to be predictors of myocardial ischemia (sensitivity 35 and 75%, respectively, specificity 37 and 81%, respectively), and criteria of objectification of zones of left ventricular wall with impaired contractility (sensitivity 51 and 75%, respectively, specificity 52 and 76%, respectively). During stress echocardiography only dynamics of myocardial IVRT reflected the state of regional left ventricular diastolic function. CONCLUSION: Stress echocardiography with transesophageal atrial pacing combined with impulse-wave tissue doppler imaging is a highly informative method of diagnosis and quantitative assessment of concealed myocardial ischemia.
Asunto(s)
Ecocardiografía Doppler de Pulso/métodos , Ecocardiografía de Estrés/métodos , Isquemia Miocárdica/diagnóstico por imagen , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Contracción Miocárdica/fisiología , Isquemia Miocárdica/fisiopatologíaRESUMEN
AIM: To study the role of hemodynamic reserve of aortic compression chamber (ACC) in compensation of coronary blood flow during stress. MATERIAL: Ninety three subjects (78 men and 15 women) including 74 patients with chronic ischemic heart disease (mean age 50-/+7 years) and 19 healthy volunteers (mean age 45-/+5 years). METHODS: Hemodynamic reserve of ACC was defined as volume of blood deposited in walls of ascending aorta at the end of systole. M-mode cross-section of ascending aorta was obtained during transesophageal pacing with long-axis view from parasternal approach. Antegrade and retrograde blood flow in the ascending aorta was registered through suprasternal approach with wave-impulse doppler. Movements of left ventricular walls were assessed via apical approach with the use of 12-segment model. The following factors were directly determined or calculated: morphometrical parameters, elasticity and rigidity of aorta, temporal and amplitudal characteristics of antegrade and retrograde flow in ascending aorta, stroke volume, cardiac output, coronary fraction of stroke volume, coronary blood flow. Results. During transesophageal pacing in healthy subjects elastic ACC despite increasing limit of diastole duration accumulated energy, pressure and part of volume of moving blood, providing sufficient flow in the coronary circulation. In patients with ischemic heart disease rigid ACC functioned as hydrodynamically inert tube being the cause of progressive diminishment of coronary flow. CONCLUSION: Decreased capacitance and functional reserves of ACC in atherosclerosis constituted the first hemodynamic barrier determining deficit of coronary blood flow during stress.
Asunto(s)
Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/fisiopatología , Vasos Coronarios/fisiopatología , Prueba de Esfuerzo/métodos , Atrios Cardíacos/diagnóstico por imagen , Atrios Cardíacos/fisiopatología , Ecocardiografía , Femenino , Hemodinámica/fisiología , Humanos , Masculino , Persona de Mediana EdadRESUMEN
AIM: To elucidate possibilities of multiplane transesophageal ultrasound for assessment of localization and structure of atherosclerotic plaques in the thoracic aorta as well as relationship between changes of elastic-tonic properties, processes of aortic wall remodeling, stage of aortic atheromatosis, and coronary atherosclerosis. MATERIAL: Patients with chronic ischemic heart disease and atherosclerosis of thoracic aorta (n=120), healthy volunteers (n=11, all men, mean age 51-/+8 years). METHODS: Multiplane transesophageal ultrasound with subsequent calculation of parameters of elasticity and stiffness. The classification of C. Pitsavos et al. (1997) was used for grading aortic atheromatosis. RESULTS. Atherosclerotic plaques were found in 109 patients (91%) and 69 patients (58%) had pronounced (stage 3-5) atheromatosis of thoracic aorta. The plaques were most frequently (87%) localized in descending aorta. Calcinated hyperdense plaques, soft plaques with low density, soft plaques with heterogeneous density prevailed in ascending aorta, aortic arch, and descending aorta, respectively. Sensitivity and specificity of thoracic atherosclerosis as predictor of atherosclerotic lesions in coronary vessels were 90 and 65%, respectively. Pronounced diffuse atherosclerosis of thoracic aorta decreased its elastic-tonic properties as evidenced by significant lowering of parameters of elasticity and increase of stiffness index. This process was associated with remodeling of thoracic aorta (progressive passive dilatation, thickening of its wall and lowering of amplitude of systolic excursion). Atheromatosis stage correlated inversely with systolic excursion and parameters of elasticity and directly with stiffness index, intima-media thickness, systolic and diastolic diameters of the aorta. There was also a direct correlation between stage of aortic atheromatosis and age and total score of coronary artery involvement. CONCLUSION: Multiplane transesophageal echocardiography is a highly informative noninvasive method of assessment of morpho-functional changes of thoracic aorta caused by atherosclerosis.
RESUMEN
AIM: To assess the role of estimation of coronary reserve in coronary sinus by transesophageal doppler during dipyridamole stress test for diagnosis of hemodynamically significant left coronary artery stenoses. MATERIAL: Patients with angiographically proven left coronary artery stenoses (n=29) and 25 healthy volunteers. METHODS: Coronary reserve was calculated as 1) ratio of peak to basal diastolic coronary flow velocity (V(p)CR), and 2) ratio of volume coronary blood flow velocity before and during hyperemia (VBF CR). Coronary reserve <2 was considered decreased. RESULTS: Compared with healthy subjects patients with coronary heart desease had significantly lower V(p)CR (1.67+/-0.44 and 2.56+/-0.87, respectively, p<0.001) and VBF CR (2.42+/-1.37 and 5.53+/-3.65, respectively, p<0.001). Sensitivity and specificity of coronary reserve below 2 for diagnosis of left coronary artery stenoses was 72 and 72%, respectively, for V(p)CR, and 49 and 96%, respectively, for VBF CR. VBF CR below 2 was a marker of severe double vessel left coronary artery disease. V(p)CR <2 was associated with single vessel stenoses within left coronary artery system. CONCLUSION: The use of evaluation of coronary reserve by transesophageal dopplerography for diagnosis of left coronary artery stenoses is methodologically correct. Level of coronary reserve in coronary sinus can be considered an integral parameter characterizing total left coronary artery atherosclerotic damage.
Asunto(s)
Estenosis Coronaria/diagnóstico por imagen , Estenosis Coronaria/fisiopatología , Ecocardiografía Transesofágica , Circulación Coronaria/fisiología , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y EspecificidadRESUMEN
Effect of 9-12 month treatment with captopril on dopplerographic parameters of intrarenal blood flow and renal function was studied in 30 hypertensive diabetics without clinical signs of nephroangiopathy. There was an interrelationship between strict blood pressure (BP) control (average 24-hour BP below 135/83) and improvement of parameters of intrarenal hemodynamics. BP normalization and most pronounced positive changes of renal perfusion during therapy with captopril were achieved in patients with mild hypertension and initially high intrarenal resistance yet at the stage of normo- or microalbuminuria. In moderate hypertension with microalbuminuria treatment with captopril was associated with stabilization of parameters of renal blood flow and rate of 24-hour albumin excretion at their initial level despite less strict control of BP and unsatisfactory compensation of diabetes. BP response to captopril in patients with hypertension and diabetes was related to initial state of intrarenal hemodynamics. In patients with mild hypertension indexes of resistance of renal and intrarenal arteries could be used for prediction of sensitivity to antihypertensive action of captopril.