RESUMEN
OBJECTIVES: This study was conducted to investigate whether pulmonary venous flow variables measured by transthoracic Doppler ultrasound can help identify patients with elevated left ventricular end-diastolic or filling pressures, or both. BACKGROUND: A widened left atrial pressure A wave occurs when left ventricular end-diastolic pressure is increased. Increased duration of pulmonary venous flow reversal at atrial systole might therefore be a marker for elevated end-diastolic pressure. Decreased systolic pulmonary venous flow is shown to be related to increased left ventricular filling pressure in studies using transesophageal Doppler echocardiography. METHODS: Left ventricular pressures at late diastole were measured by fluid-filled catheters in 50 consecutive patients undergoing diagnostic cardiac catheterization. Pulmonary venous and mitral flow velocities were recorded by transthoracic pulsed Doppler ultrasound. RESULTS: Adequate recordings were obtained in 45 patients. Pulmonary venous flow reversal exceeding the duration of the mitral A wave predicted left ventricular end-diastolic pressure > 15 mm Hg with a sensitivity of 0.85 and a specificity of 0.79. This difference in flow duration correlated well with the increase in ventricular pressure (r = 0.70, p < 0.001) at atrial systole and the end-diastolic pressure (r = 0.68, p < 0.001). The systolic fraction of pulmonary venous flow was markedly decreased (< 0.4) in all patients with a pre-A pressure (left ventricular pressure before atrial systole) > 18 mm Hg. CONCLUSIONS: Pulmonary venous flow reversal exceeding the duration of the mitral A wave indicates an exaggerated increase in left ventricular late diastolic pressure. Pulmonary venous systolic fraction < 0.4 suggests markedly increased ventricular filling pressure.
Asunto(s)
Enfermedad Coronaria/fisiopatología , Diástole/fisiología , Ecocardiografía Doppler , Venas Pulmonares/diagnóstico por imagen , Venas Pulmonares/fisiología , Función Ventricular Izquierda/fisiología , Adolescente , Adulto , Anciano , Velocidad del Flujo Sanguíneo , Presión Sanguínea , Enfermedad Coronaria/diagnóstico por imagen , Femenino , Cardiopatías/diagnóstico por imagen , Cardiopatías/fisiopatología , Enfermedades de las Válvulas Cardíacas/diagnóstico por imagen , Enfermedades de las Válvulas Cardíacas/fisiopatología , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Válvula Mitral/fisiopatologíaRESUMEN
In patients with restriction of cardiac filling of various origins, cardiac catheterization has been traditionally used as part of the diagnostic evaluation to verify the presence of restrictive/constrictive hemodynamics. In an attempt to determine whether this "restrictive" physiology could be demonstrated noninvasively, 14 patients who had a history, physical examination, two-dimensional echocardiogram and catheterization data compatible with a restrictive myocardial process were studied with pulsed wave Doppler ultrasound. Forty normal subjects served as a control group. The Doppler ultrasound evaluation included measurement of peak mitral and tricuspid flow velocities and flow velocity integrals, mitral and tricuspid deceleration times and central venous flow patterns during apnea and inspiration. The flow velocity recordings across the mitral and tricuspid valves in patients manifesting restriction were markedly different from those in normal subjects, showing shortened deceleration times across both valves, which indicated both an abrupt premature cessation of ventricular filling and the presence of a diastolic dip-plateau contour in ventricular pressure recordings. In addition, abnormal central venous flow velocity reversals with inspiration and diastolic mitral and tricuspid regurgitation were frequently observed, also suggesting the reduced myocardial compliance characteristic of a restrictive myocardial process.
Asunto(s)
Cardiomiopatía Restrictiva/fisiopatología , Ecocardiografía , Corazón/fisiopatología , Válvula Mitral/fisiopatología , Válvula Tricúspide/fisiopatología , Adulto , Anciano , Velocidad del Flujo Sanguíneo , Trasplante de Corazón , Enfermedades de las Válvulas Cardíacas/fisiopatología , Ventrículos Cardíacos/fisiopatología , Hemodinámica , Humanos , Persona de Mediana Edad , Contracción Miocárdica , Respiración , Volumen SistólicoRESUMEN
Cardiac tamponade has been associated with an abnormally increased respiratory variation in transvalvular blood flow velocities. To determine whether this finding is consistently present in cardiac tamponade, seven patients were studied prospectively with Doppler echocardiography before and after pericardiocentesis and the results were compared with those found in 20 normal adults and 14 asymptomatic patients with pericardial effusion who did not have definite clinical evidence of tamponade. Doppler ultrasound evaluation included measurement of mitral, tricuspid, aortic, pulmonary and central venous flow velocities, as well as left ventricular ejection and isovolumic relaxation times during inspiration, expiration and apnea. In the patients with severe cardiac tamponade, respiratory variation in transvalvular flow velocities and left ventricular ejection and isovolumic relaxation times were markedly increased compared with values in normal subjects and those obtained after pericardiocentesis. In the 14 asymptomatic patients with pericardial effusion but without overt tamponade, 7 showed respiratory variation in flow velocity similar to that of normal subjects. The other seven patients demonstrated increased respiratory change compared with normal, but less than that in the patients with tamponade. Clinical and hemodynamic data in this latter group suggest that these patients may represent an intermediate stage of pericardial effusion with an element of hemodynamic compromise.
Asunto(s)
Velocidad del Flujo Sanguíneo , Taponamiento Cardíaco/fisiopatología , Ecocardiografía , Válvulas Cardíacas/fisiopatología , Derrame Pericárdico/fisiopatología , Respiración , Adulto , Taponamiento Cardíaco/cirugía , Electrocardiografía , Estudios de Evaluación como Asunto , Estudios de Seguimiento , Hemodinámica , Humanos , Persona de Mediana Edad , Pericardio/cirugía , Fonocardiografía , Estudios Prospectivos , Pulso Arterial , Volumen Sistólico , Vena Cava Superior/fisiopatologíaRESUMEN
The purpose of this study was to prospectively determine the incidence of diastolic mitral and tricuspid regurgitation in atrioventricular (AV) block using Doppler echocardiography. The temporal relation between mitral and tricuspid diastolic insufficiency and the diastolic murmur recorded in patients with complete heart block was also investigated. Twenty-two consecutive patients with AV block (referred to the Echo-Doppler laboratory for routine clinical studies), aged 18 to 87 years, were enrolled in the study. Eleven patients had third degree AV block and a ventricular-inhibited (VVI) pacemaker, two patients had second degree AV block, seven patients had first degree AV block, one patient had blocked premature atrial complexes and one patient had atrial flutter with 4:1 AV block. Diastolic mitral regurgitation was detected in 20 patients, and diastolic tricuspid regurgitation in 21. A mid-diastolic murmur was detected in all patients except in the three youngest. The murmur occurred before diastolic regurgitation and coincided with peak forward flow through the AV valve after atrial contraction. M-mode mitral valve echocardiograms obtained in nine patients demonstrated near closure of some portions of the mitral valve after atrial contraction. Effective closure of the valve, however, did not occur unless ventricular systole supervened. In conclusion, diastolic mitral and tricuspid regurgitation are almost universally present in patients with AV block and are associated with a diastolic murmur. The murmur coincides with forward AV valve flow. Diastolic regurgitation is silent. Effective AV valve closure is not established until ventricular systole occurs, as demonstrated by M-mode echocardiographic recording of the mitral valve.
Asunto(s)
Bloqueo Cardíaco/complicaciones , Insuficiencia de la Válvula Mitral/etiología , Insuficiencia de la Válvula Tricúspide/etiología , Adulto , Anciano , Anciano de 80 o más Años , Diástole , Ecocardiografía , Electrocardiografía , Femenino , Soplos Cardíacos , Humanos , Masculino , Persona de Mediana Edad , Válvula Mitral/fisiopatología , Insuficiencia de la Válvula Mitral/diagnóstico , Factores de Tiempo , Válvula Tricúspide/fisiopatología , Insuficiencia de la Válvula Tricúspide/diagnósticoRESUMEN
Pulsed wave Doppler ultrasound recordings of blood flow velocity in the superior vena cava were made in 40 healthy adults (aged 22 to 69 years) during both normal respiration and 10 second episodes of apnea. The forward flow velocity pattern was biphasic, with systolic flow velocity greater than diastolic flow velocity. During apnea, peak flow velocities ranged from 32 to 69 cm/s (mean 45.7 +/- 8.4) during systole and from 6 to 45 cm/s (mean 27.2 +/- 8.3) in early diastole. Systolic flow velocity integrals also exceeded diastolic values. With atrial systole (A wave), forward flow velocities were reduced or flow was reversed. Thirty-nine of 40 subjects had A wave flow reversal during apnea, and in these the ratio of reverse to total forward flow velocity integrals ranged from 1 to 16% (mean 6 +/- 4%). Compared with values during apnea, there were higher mean values with inspiration and lower values with expiration for velocities and flow velocity integrals. Hepatic vein tracings, when adequate (12 of 40 subjects), showed forward flow characteristics similar to those from the superior vena cava, but with more frequent and larger A wave and ventricular end-systole (atrial V wave) flow reversals. Superior vena cava flow velocity variables were calculated in subgroups to assess the effects of age, respiratory pattern and increased venous return. This study defines normal Doppler ultrasound superior vena cava and hepatic vein flow velocities and their variation with respiration in healthy adults. These results can be used for comparison with patterns found in disease states.
Asunto(s)
Ecocardiografía , Venas Hepáticas/fisiología , Vena Cava Superior/fisiología , Adulto , Factores de Edad , Anciano , Velocidad del Flujo Sanguíneo , Frecuencia Cardíaca , Humanos , Persona de Mediana Edad , Contracción Miocárdica , RespiraciónRESUMEN
In an effort to determine what clinically useful information regarding left ventricular diastolic function can be inferred noninvasively with pulsed wave Doppler echocardiography, mitral flow velocity patterns and measured variables were correlated with hemodynamic findings in 70 patients: 30 with coronary artery disease, 20 with idiopathic congestive cardiomyopathy, 14 with a restrictive myocardial process and 6 without significant cardiac disease. The effect of sudden changes in hemodynamics on the mitral flow velocity pattern was also investigated in a subgroup of patients who had simultaneous recording of mitral flow velocity and left ventricular pressure before and after left ventriculography. Mitral flow velocity recordings from 30 healthy adults served as a reference group. This analysis suggests that 1) the majority of patients with these cardiac disorders demonstrate abnormal mitral flow velocity patterns or variables; 2) markedly different flow velocity patterns can be seen in patients with impaired left ventricular relaxation; 3) the different mitral patterns appear to relate more to myocardial function and hemodynamic status than to the type of disease process present; 4) certain mitral patterns suggest different filling pressures and rates of early diastolic left ventricular filling; 5) an increase in left atrial pressure can "normalize" an abnormal mitral flow velocity pattern and "mask" a left ventricular relaxation abnormality; and 6) the different patterns appear to represent a dynamic continuum with the potential to change from one to another as a result of disease progression, medical therapy or sudden changes in hemodynamics. It is concluded that, despite the indirect method of estimation and certain limitations, mitral flow velocity recordings have clinical potential in assessing left ventricular diastolic function that merits further investigation.
Asunto(s)
Velocidad del Flujo Sanguíneo , Diástole , Ecocardiografía , Corazón/fisiopatología , Válvula Mitral , Contracción Miocárdica , Adulto , Cateterismo Cardíaco , Cardiomiopatía Dilatada/fisiopatología , Cardiomiopatía Restrictiva/fisiopatología , Enfermedad Coronaria/fisiopatología , Cardiopatías/fisiopatología , Frecuencia Cardíaca , Humanos , Persona de Mediana Edad , Válvula Mitral/fisiopatología , Insuficiencia de la Válvula Mitral/fisiopatología , Presión , Presión Esfenoidal PulmonarRESUMEN
To evaluate the hemodynamic changes occurring with percutaneous aortic balloon valvuloplasty for aortic stenosis, Doppler echocardiography was performed during the procedure in 16 patients. During balloon inflation, peak velocity and ejection time of the aortic valve systolic signals increased (26 and 30%, respectively; p less than 0.001). Aortic regurgitation deceleration time decreased from 1,337 to 625 ms (p less than 0.001). In three patients, aortic regurgitation stopped before end-diastole; in four patients, end-diastole forward flow across the aortic valve was documented. The deceleration time of the mitral valve inflow signal decreased from 303 to 194 ms (p less than 0.001) during balloon inflation, concurrently with an increase in left ventricular diastolic pressure. Mitral regurgitation signals became more prominent during inflation in 10 patients. Changes that occur during balloon inflation in the aortic valve include progressive left ventricular outflow obstruction, equalization of diastolic aortic and left ventricular pressures and changes in diastolic compliance.
Asunto(s)
Estenosis de la Válvula Aórtica/fisiopatología , Calcinosis/fisiopatología , Cateterismo , Ecocardiografía , Hemodinámica , Anciano , Anciano de 80 o más Años , Insuficiencia de la Válvula Aórtica/fisiopatología , Estenosis de la Válvula Aórtica/terapia , Velocidad del Flujo Sanguíneo , Presión Sanguínea , Calcinosis/terapia , Femenino , Humanos , Masculino , Insuficiencia de la Válvula Mitral/fisiopatologíaRESUMEN
The continuous wave Doppler ultrasound signal across the left ventricular outflow tract in hypertrophic cardiomyopathy has a characteristic pattern that is in keeping with the dynamic nature of the pressure gradient in this condition. To determine the accuracy and reliability of the peak Doppler flow velocity signal for measuring the peak pressure gradient in this condition, 340 beats were analyzed from five consecutive patients studied with simultaneous continuous wave Doppler ultrasound and dual catheter pressure recordings across the left ventricular outflow tract. Each patient was studied at steady state and during physiologic and pharmacologic manipulations of the pressure gradient. Peak velocity and calculated peak gradient were determined by two independent observers who did not know the catheter measurements. In addition, 18 beats with well defined flow velocity envelopes were digitized for analysis of the magnitude, timing and contour of the instantaneous Doppler ultrasound and catheter gradients throughout systole. Peak catheter gradient in the 340 beats ranged from 12 to 245 mm Hg. The correlations between the Doppler-derived and catheter peak gradients were close (r = 0.96, SEE = 4 mm Hg for Observer 1 and r = 0.97, SEE = 11 mm Hg for Observer 2). Interobserver variability for measurement of peak flow velocity was small (mean +/- SD 0.16 +/- 0.15 m/s). An interobserver difference greater than 0.3 m/s occurred in 25 of the 340 beats analyzed. By retrospective analysis, this was due to contamination of the outflow tract signal by mitral regurgitation.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Presión Sanguínea , Cardiomiopatía Hipertrófica/fisiopatología , Ecocardiografía , Adulto , Anciano , Velocidad del Flujo Sanguíneo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obstrucción del Flujo Ventricular Externo/fisiopatologíaRESUMEN
In symptomatic severe aortic regurgitation, left ventricular diastolic pressure increases rapidly, often exceeding left atrial pressure in late diastole. This characteristic hemodynamic change should be reflected in the Doppler mitral inflow velocity, which is the direct result of the diastolic pressure difference between the left ventricle and left atrium. Mitral inflow velocity was obtained by pulsed wave Doppler echocardiography in 11 patients (6 men, 5 women: mean age 53 years) with severe symptomatic aortic regurgitation and compared with normal values from 11 sex- and age-matched control subjects. The following Doppler variables were determined: velocity of early filling wave (E), velocity of late filling wave due to atrial contraction (A), E to A ratio (E/A), deceleration time and pressure half-time. In severe aortic regurgitation, E and E/A (1.13 m/s and 3.3, respectively) were significantly higher (p less than 0.001) than normal (0.60 m/s and 1.5, respectively). Deceleration time and pressure half-time (117 and 34 ms, respectively) were significantly shorter (p less than 0.001) than normal (203 and 59 ms, respectively). Late filling wave velocity (A) was not statistically different in the two groups, although it tended to be lower in the patient group (0.39 versus 0.50 m/s). Diastolic mitral regurgitation was present in eight patients (73%). M-mode echocardiography of the mitral valve, performed in 10 patients, showed that only 3 (30%) had premature mitral valve closure. In symptomatic severe aortic regurgitation, the Doppler mitral inflow velocity pattern is characteristic, with increased early filling wave velocity (E) and early to late filling wave ratio (E/A) and decreased deceleration time of the E wave.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Insuficiencia de la Válvula Aórtica/fisiopatología , Ecocardiografía Doppler , Válvula Mitral/fisiopatología , Adulto , Anciano , Válvula Aórtica/cirugía , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
A spectrum of left ventricular diastolic filling abnormalities noted on Doppler echocardiography has been demonstrated in patients with cardiac amyloidosis. To determine how these filling abnormalities evolve over time and the significance of any change, serial pulsed wave Doppler studies of left ventricular inflow were performed over 12.6 +/- 4.9 months in 41 consecutive patients (36 men and 15 women, mean age 59 +/- 11 years) with typical two-dimensional echocardiographic features of cardiac involvement. The measurements were peak left ventricular inflow in early diastole (E) and atrial contraction (A) velocities, E/A ratio, deceleration time and isovolumetric relaxation time. Patients were classified by mean left ventricular wall thickness into an early group (less than 15 mm) of 24 patients and an advanced group (greater than or equal to 15 mm) of 17 patients. The total group showed an increased E/A ratio (1.7 +/- 0.9 versus 1.4 +/- 0.9, p = 0.009) and decreased deceleration time (164 +/- 57 versus 174 +/- 51 ms, p = 0.11) at follow-up compared with baseline study. The early group showed significant changes in the E/A ratio (1.6 +/- 1.0 versus 1.2 +/- 0.7, p = 0.001) between the two studies. Seven patients (29%) in the early group showed a change from an abnormal relaxation or "normal" pattern to one of restriction, coincident with increased symptoms in six of these patients. Fifteen (88%) of the 17 patients in the advanced group did not show significant changes in the measures during the follow-up study, but these patients already showed a restrictive pattern.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Amiloidosis/diagnóstico por imagen , Cardiomiopatías/diagnóstico por imagen , Ecocardiografía Doppler , Función Ventricular Izquierda/fisiología , Amiloidosis/fisiopatología , Cardiomiopatías/fisiopatología , Circulación Coronaria/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Contracción Miocárdica/fisiología , Factores de TiempoRESUMEN
To assess right ventricular diastolic function in cardiac amyloidosis, pulsed wave Doppler ultrasound measurements of right ventricular inflow velocities and superior vena cava and hepatic vein flow velocities with respiratory monitoring were performed in 41 patients with primary systemic amyloidosis and two-dimensional echocardiographic features of cardiac involvement. Right ventricular diastolic function was abnormal in 31 (76%) of these patients, the major abnormality being a short deceleration time (less than 150 ms) in 21 (68%), suggesting restriction. In contrast, 7 (23%) of the 31 patients had a decreased ratio of early (E) and late (A) diastolic peak flow velocities and a prolonged deceleration time (greater than 240 ms), suggesting abnormal relaxation. The patients were classified into two groups on the basis of right ventricular free wall thickness: group 1, less than 7 mm and group 2, greater than or equal to 7 mm. Compared with normal values, group 1 showed an increased peak late flow velocity (44 +/- 19 versus 39 +/- 6 cm/s; p less than 0.01) and a decreased E/A velocity ratio (1.1 +/- 0.4 versus 1.5 +/- 0.3; p less than 0.01). Group 2 showed a markedly shortened deceleration time (151 +/- 37 versus 225 +/- 28 ms; p less than 0.01), characteristic of restriction. In the overall group, superior vena cava peak flow velocity was decreased in systole and increased in diastole and flow reversals during inspiration were increased compared with normal values. Hepatic venous flow velocities were similar to those in the superior vena cava except for larger flow reversals in the hepatic vein. Thus, in cardiac amyloidosis, right ventricular diastolic function is abnormal. There is a spectrum of right ventricular filling abnormalities and the restrictive filling pattern is seen only in the advanced stages of the disease.
Asunto(s)
Amiloidosis/diagnóstico , Cardiomiopatías/diagnóstico , Ecocardiografía Doppler , Contracción Miocárdica/fisiología , Amiloidosis/fisiopatología , Velocidad del Flujo Sanguíneo , Cardiomiopatías/fisiopatología , Femenino , Venas Hepáticas/fisiología , Humanos , Masculino , Persona de Mediana Edad , Insuficiencia de la Válvula Tricúspide/diagnóstico , Vena Cava Superior/fisiologíaRESUMEN
Sixty-four patients with primary systemic amyloidosis-53 with two-dimensional echocardiographic features of cardiac involvement (Group I) and 11 without cardiac involvement (Group II)--underwent Doppler echocardiographic assessment of left ventricular diastolic function. Pulsed wave Doppler recordings of left ventricular inflow velocities and pulmonary vein flow velocities with respiratory monitoring in these patients were compared with findings in a normal group. Patients in Group I showed striking abnormalities of left ventricular diastolic filling when classified into subgroups by mean left ventricular wall thickness: early greater than 12 but less than 15 mm; advanced greater than or equal to 15 mm. In early amyloidosis, relaxation was abnormal, with decreased peak early velocity (75 +/- 20 versus 86 +/- 16 cm/s; p less than 0.01), increased late velocity (71 +/- 22 versus 56 +/- 13 cm/s; p less than 0.01), decreased early to late velocity ratio (1.2 +/- 0.6 versus 1.6 +/- 0.5; p less than 0.01) and prolonged isovolumic relaxation time (87 +/- 15 versus 73 +/- 13 ms; p less than 0.01) compared with normal values. In advanced amyloidosis, there was a restrictive filling pattern with a markedly shortened deceleration time (148 +/- 50 versus 199 +/- 32 ms; p less than 0.001), decreased pulmonary vein peak systolic flow velocity (34 +/- 16 versus 54 +/- 12 cm/s; p less than 0.01) and increased diastolic flow velocity (55 +/- 20 versus 44 +/- 12 cm/s; p less than 0.01) compared with normal values. Group and the subgroup with early amyloidosis had similar flow velocity patterns. Thus, this study documents that in cardiac amyloidosis, a spectrum of diastolic filling abnormalities exists; the restrictive filling pattern is seen only in the advanced stages.
Asunto(s)
Amiloidosis/fisiopatología , Diástole , Cardiopatías/fisiopatología , Corazón/fisiopatología , Contracción Miocárdica , Ultrasonografía , Amiloidosis/complicaciones , Amiloidosis/patología , Velocidad del Flujo Sanguíneo , Circulación Coronaria , Ecocardiografía , Femenino , Cardiopatías/complicaciones , Ventrículos Cardíacos , Humanos , Masculino , Persona de Mediana Edad , Insuficiencia de la Válvula Mitral/complicaciones , Miocardio/patología , Venas Pulmonares/fisiopatología , SístoleRESUMEN
OBJECTIVES: This study was conducted to assess the diagnostic role of Doppler echocardiography in constrictive pericarditis. BACKGROUND: It has been observed that patients with constrictive pericarditis have a characteristic Doppler pattern of respiratory variation in ventricular filling and central venous flow velocities. However, the observation was based on a small number of patients with known diagnosis. METHODS: We reviewed the echocardiographic features of 28 patients (21 men and 7 women; mean age +/- SD 55 +/- 15 years) with suspected constrictive pericarditis who underwent exploratory thoracotomy or pericardiectomy. RESULTS: At operation, constrictive pericarditis was diagnosed in 25 patients, restriction in 1 and normal pericardium in 2. Of the 25 patients with constriction, correct preoperative Doppler diagnosis was made in 22 (88%) and Doppler echocardiography showed restriction in 3. In two patients with a normal pericardium, Doppler features were consistent with constriction in one patient and were normal in the other. In the one patient with restriction, Doppler echocardiography showed restriction. In 19 patients with surgically proved constriction, repeat Doppler study after pericardiectomy showed normal findings in 14 and restriction in 5. Twelve of the 14 patients with normalized Doppler findings became asymptomatic, whereas all 5 with restrictive Doppler features remained symptomatic. CONCLUSIONS: Doppler echocardiography performed simultaneously with respiratory recording is highly sensitive for diagnosing constrictive pericarditis, and it appears to predict functional response to pericardiectomy.
Asunto(s)
Ecocardiografía Doppler , Pericarditis Constrictiva/diagnóstico por imagen , Adulto , Anciano , Velocidad del Flujo Sanguíneo , Femenino , Hemodinámica , Humanos , Masculino , Persona de Mediana Edad , Pericardiectomía , Pericarditis Constrictiva/fisiopatología , Pericarditis Constrictiva/cirugía , Valor Predictivo de las Pruebas , Estudios ProspectivosRESUMEN
Recipient atrial remnants retain electrical and mechanical activity after orthotopic cardiac transplantation. This study investigated the influence of recipient atrial contraction timing on Doppler ultrasound mitral flow velocity curves, isovolumic relaxation time, peak early mitral flow velocity (M1), mitral valve pressure half-time and peak mitral flow velocity due to atrial systole (M2). Clearly identifiable recipient atrial electrical activity (P waves) was present in 7 of 10 patients studied early postoperatively 2 to 6 months (mean 2.5) (early group) and in 20 of 24 patients seen 1 to 11 years (mean 3) after transplantation (late group). Median age and gender distribution were similar in both groups. For analysis of its influence on isovolumic relaxation time, pressure half-time and M1, recipient atrial contraction was classified by its position in the cardiac cycle as early systole, late systole or diastole. For analysis of M2, it was classified as early diastole, late diastole or systole. Compared with its occurrence in diastole, recipient atrial contraction in late systole was associated with a shorter isovolumic relaxation time, shorter pressure half-time and higher M1. In early systole it was associated with a longer pressure half-time and lower M1 than in diastole; isovolumic relaxation time was unchanged. Recipient atrial contraction in early diastole resulted in a lower M2 than in systole, whereas simultaneous contraction of recipient and donor atria in late diastole resulted in an increase in M2. These results indicate that the timing of recipient atrial contraction and relaxation significantly influences left ventricular filling dynamics.
Asunto(s)
Ecocardiografía , Trasplante de Corazón , Contracción Miocárdica , Adulto , Velocidad del Flujo Sanguíneo , Volumen Cardíaco , Femenino , Rechazo de Injerto , Corazón/fisiopatología , Atrios Cardíacos , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Patients with constrictive pericarditis usually require pericardiectomy to relieve their symptoms. In some patients, however, constrictive pericarditis may resolve spontaneously or with medical treatment. Four patients with transient constrictive pericarditis are described in this report. Although the cause of pericarditis differed, all patients had a small to large amount of pericardial effusion, followed by symptoms, signs, and Doppler features typical of constrictive pericarditis. Symptomatic improvement occurred after treatment with some combination of nonsteroidal anti-inflammatory agents, corticosteroids, and antibiotics. The resolution of the symptoms paralleled the normalization of characteristic respiratory changes in Doppler flow velocities. The condition of our patients most likely was related to a transient inflammation (or thickening) of the pericardium due to viral, bacterial, or immunologically mediated pericarditis. Resolution of the thickened pericardium was documented by magnetic resonance imaging in one patient. Awareness of the possible transient nature of constrictive pericarditis in a subgroup of patients with constriction has important clinical implications when pericardiectomy is considered. The resolution of constrictive pericarditis can be documented by serial Doppler echocardiographic examination.
Asunto(s)
Ecocardiografía Doppler , Pericarditis Constrictiva/diagnóstico por imagen , Adulto , Anciano , Velocidad del Flujo Sanguíneo , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Pericarditis Constrictiva/diagnóstico , Pericarditis Constrictiva/fisiopatología , Pericardio/patologíaRESUMEN
In the past, evaluation of the myocardium has been limited to examining systolic function of the heart. Recently, however, investigators have demonstrated that abnormalities of diastolic function of the heart provide important contributions to the signs and symptoms experienced by patients with heart disease. In addition, abnormalities of diastolic function may precede abnormalities of systolic function in the early stages of disease. Diastolic filling of the heart, however, is a complex sequence of interrelated events. In order to understand diastolic function, each of these factors contributing to filling of the heart must be examined. They include relaxation, passive compliance, atrial contraction, erectile effect of the coronary arteries, viscoelastic properties, ventricular interaction, and pericardial restraint--all of which are interrelated. In addition, diastolic factors are affected by changes in loading conditions and contractility, and they demonstrate nonuniformity in time and space. This report provides an overview of these various factors from the clinical perspective, based on studies involving the isolated papillary muscle and the isolated heart as well as basic clinical studies.
Asunto(s)
Diástole , Ecocardiografía Doppler , Contracción Miocárdica , Animales , Corazón/fisiología , Corazón/fisiopatología , HumanosRESUMEN
Evaluation of diastolic filling of the heart has been difficult because of its complexity and the numerous interrelated contributing factors. Previous determinations have depended on high-fidelity, invasive measurements of instantaneous pressure, volume, mass, and wall stress, which could not be done on a routine clinical basis. With the advent of Doppler echocardiography, intracardiac blood flow velocities can now be noninvasively assessed. For application of this technique to evaluation of diastolic function in patients with heart disease, it is necessary to understand what the Doppler-derived variables represent. It is also necessary to know how they are affected by changes in loading conditions and changes in myocardial relaxation. In this review, we provide an interpretation of the mitral valve, tricuspid valve, and systemic and pulmonary venous inflow velocities in the normal patient and in various disease states.
Asunto(s)
Diástole , Ecocardiografía Doppler , Cardiopatías/fisiopatología , Contracción Miocárdica , Velocidad del Flujo Sanguíneo , Humanos , Válvula Mitral/fisiologíaRESUMEN
This study examines the reproducibility and variability of pulsed wave Doppler versus continuous wave Doppler ultrasound indexes of left ventricular filling in cardiac allograft recipients and in normal subjects. The following indexes were studied: isovolumic relaxation time, pressure half-time, peak early mitral flow velocity, and peak mitral flow velocity after atrial systole. Intraobserver and interobserver variability were assessed by regression analysis. Individual components of variance (subject, reader, beat, day, and tracing) were estimated in a subset of five patients and five normal subjects, and estimated total variance defined for each group. Temporal (day-to-day) variability for 95% confidence was estimated for these patients and for normal subjects. Temporal variability in the group from which the subsets were drawn was measured from absolute and percent change in values on two occasions. Estimated and observed 95% confidence limits were compared. Intersubject variability was the largest component of variance in both transplant recipients and in normal subjects. For all indexes in transplant recipients (in the absence of rejection) and normal subjects, observed absolute mean differences (+/- 2 standard deviations) between values from recordings taken on two different days were larger than the 95% confidence limits estimated from the components of variance analysis. The observed 95% limits for transplant recipients versus normal subjects were as follows: isovolumic relaxation time, 20 msec versus 6 msec; pressure half-time, 16 msec versus 9 msec; peak early mitral flow velocity, 32 cm per second versus 17 cm per second; and peak mitral flow velocity after atrial systole, 28 cm per second versus 10 cm per second.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Ecocardiografía Doppler , Ecocardiografía , Trasplante de Corazón/fisiología , Función Ventricular Izquierda/fisiología , Adulto , Análisis de Varianza , Femenino , Rechazo de Injerto , Humanos , Masculino , Variaciones Dependientes del Observador , Valores de Referencia , Análisis de Regresión , Reproducibilidad de los ResultadosRESUMEN
Doppler echocardiography is a sensitive method to detect mitral regurgitation in patients with both native and prosthetic valves. However, estimates of the amount of mitral regurgitation remain semiquantitative, and even severe mitral regurgitation may be underestimated in the presence of markedly eccentric regurgitant jets or acoustic shadowing of the left atrium by mitral or aortic prostheses. This report describes the Doppler findings in 10 patients with severe native valve mitral regurgitation (angiographic grade III or IV) and in 15 patients with severe bioprosthetic mitral regurgitation that required valve replacement. An increase in peak mitral flow velocity above normal values was seen in eight of 10 patients with severe native valve mitral regurgitation (greater than or equal to 130 cm per second) and 11 of 15 patients with severe prosthetic valve mitral regurgitation (greater than or equal to 210 cm per second). One of 10 patients with a native valve and four of 15 patients with a bioprosthetic valve appeared to have only a localized left atrial systolic flow disturbance, incorrectly suggesting that the mitral regurgitation was mild. However, in all patients with severe mitral regurgitation, a low velocity (less than 100 cm per second) flow signal could be recorded in the left ventricle that was directed toward the mitral valve in systole. This flow signal showed a gradual increase in velocity as the sample volume was moved toward the mitral valve, with an abrupt further increase on entry into the left atrium. This signal was continuous with antegrade mitral flow and had the same orientation as mitral regurgitation recorded by continuous wave technique from the apex. A similar flow signal was not recorded in the left ventricle of any individual in a control group of 30 patients who had no mitral regurgitation or who had angiographic grade I or II mitral regurgitation. These findings suggest that acceleration of left ventricle flow toward the mitral valve in systole is only recorded when there is hemodynamically significant mitral regurgitation that is approximately equal to angiographic grade III or IV. Recognition of this Doppler finding may help in the estimation of mitral regurgitation severity, especially in difficult diagnostic situations.
Asunto(s)
Ecocardiografía Doppler , Insuficiencia de la Válvula Mitral/diagnóstico , Anciano , Velocidad del Flujo Sanguíneo , Cateterismo Cardíaco , Ecocardiografía , Femenino , Prótesis Valvulares Cardíacas , Ventrículos Cardíacos/fisiopatología , Hemodinámica , Humanos , Masculino , Persona de Mediana Edad , Insuficiencia de la Válvula Mitral/fisiopatología , Insuficiencia de la Válvula Mitral/cirugíaRESUMEN
Doppler mitral flow velocities and related variables are used to assess left (LV) and right ventricular filling and, indirectly, ventricular diastolic function. Three abnormal ventricular filling patterns (impaired relaxation and pseudonormal and restrictive physiology) are recognized in patients with various heart diseases and have been related to alterations in LV diastolic properties and filling pressures. More recently, these variables have been used to assess the hemodynamic effects of drug therapy or heart surgery and prognosis in patients with restrictive and dilated cardiomyopathies. Despite these encouraging results, widespread clinical use of these Doppler techniques has been hampered by difficulties in obtaining accurate and reproducible measurements from Doppler flow velocity recordings. This is due, in part, to an underappreciation of factors such as cardiac filling mechanics, Doppler examination principles, and ultrasound machine settings, which can markedly affect the quality of the flow velocity recordings. The purpose of this article is to provide the technical information for performing a systematic and comprehensive Doppler evaluation of LV diastolic function that can be used on a routine basis. This information includes discussing the different flow velocity recordings required for a Doppler assessment of LV diastolic function, their proper recording technique, and the common technical pitfalls.