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1.
J Am Coll Cardiol ; 24(3): 663-70, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8077536

RESUMO

OBJECTIVES: The present study aimed to investigate the mechanism of intracavitary changes in filling pattern during acute ischemic left ventricular failure and during beta-adrenergic blockade. BACKGROUND: Recent clinical studies with color M-mode Doppler imaging have shown abnormal intracavitary filling patterns in the diseased ventricle. METHODS: In open chest anesthetized dogs with intracardiac micromanometers and myocardial segment-length crystals, global ischemic left ventricular failure was induced (n = 8) by coronary microembolization. In nonischemic ventricles inotropy was decreased (n = 6) by intravenous propranolol and increased (n = 6) by intravenous isoproterenol. From color M-mode Doppler images we calculated the time difference between peak early diastolic filling velocity at the mitral tip and apex using computer analysis. The time difference of peak velocity was used as an index of the timing of apical filling. RESULTS: There was marked retardation of apical filling with microembolization and propranolol. Time difference of peak velocity increased from 20 +/- 6 (mean +/- SEM) to 101 +/- 17 ms (p < 0.05) and from 21 +/- 8 to 80 +/- 18 ms (p < 0.05), respectively. Time constant of isovolumic relaxation increased from 34 +/- 3 to 43 +/- 5 ms (p < 0.05) and from 31 +/- 1 to 39 +/- 3 ms (p < 0.05) during microembolization and beta-blockade, respectively. Isoproterenol tended to cause the opposite changes. Time difference of peak velocity showed a positive correlation with time constant of isovolumic relaxation (r = 0.89, p < 0.01) and a negative correlation with peak early transmitral pressure gradient (r = 0.88, p < 0.01). In the intact left ventricle, peak apical filling velocity coincided with peak early transmitral pressure gradient. During ischemic failure however, peak apical filling velocity occurred 53 +/- 14 ms after peak early transmitral pressure gradient had decreased to zero and at a time when transmitral flow had ceased, suggesting a change in intraventricular flow distribution. CONCLUSIONS: Color M-mode Doppler imaging revealed retarded apical filling during depression of myocardial function by global myocardial ischemia or beta-blockade. The abnormal filling pattern may be a sign of impaired left ventricular relaxation.


Assuntos
Ecocardiografia Doppler , Função Ventricular Esquerda , Animais , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Baixo Débito Cardíaco/diagnóstico por imagem , Baixo Débito Cardíaco/etiologia , Baixo Débito Cardíaco/fisiopatologia , Diástole/efeitos dos fármacos , Cães , Feminino , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/fisiopatologia , Masculino , Valva Mitral/fisiopatologia , Isquemia Miocárdica/complicações , Propranolol/farmacologia , Função Ventricular Esquerda/efeitos dos fármacos , Pressão Ventricular/efeitos dos fármacos
2.
J Am Coll Cardiol ; 37(3): 726-30, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11693743

RESUMO

OBJECTIVES: We sought to evaluate if echocardiographic strain measurements could detect acute myocardial ischemia, and to compare this new method with myocardial velocity measurements and wall motion score index. BACKGROUND: Tissue Doppler echocardiography (TDE) is a promising method for assessing regional myocardial function. However, myocardial velocities measured by tissue Doppler echocardiography (TDE) vary throughout the left ventricle (LV) because of tethering effects from adjacent tissue. Strain Doppler echocardiography (SDE) is a new tool for measuring regional myocardial deformation excluding the effect of adjacent myocardial tissue. METHODS: Seventeen patients undergoing angioplasty of the left anterior descending coronary artery (LAD) were studied. Left ventricular longitudinal wall motion was assessed by TDE and SDE from the apical four-chamber view before, during and after angioplasty from multiple myocardial segments simultaneously. RESULTS: Systolic strain values were uniformly distributed in the different nonischemic LV segments, whereas systolic velocities decreased from basis to apex. During LAD occlusion, strain measurement showed expansion in the apical septal segment in 16 of 17 patients (7.5 +/- 6.5% vs. -17.7 +/- 7.2%, p < 0.001) and reduced compression in the mid-septal segment (p < 0.05) compared with baseline. Segments not supplied by LAD remained unchanged. Tissue Doppler echocardiography showed reduced velocities in all septal segments (p < 0.05) during angioplasty even though LAD does not supply the basal septal segment. Negative systolic velocities were present in 11 of 17 patients. Wall motion score index increased during ischemia (1.3 +/- 0.4, p < 0.05). CONCLUSIONS: The new SDE approach might be a more accurate marker than TDE for detecting systolic regional myocardial dysfunction induced by LAD occlusion.


Assuntos
Angina Pectoris/diagnóstico por imagem , Angina Pectoris/fisiopatologia , Ecocardiografia Doppler/métodos , Processamento de Imagem Assistida por Computador , Sístole/fisiologia , Idoso , Angioplastia com Balão , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
3.
Transplantation ; 72(1): 107-11, 2001 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-11468543

RESUMO

BACKGROUND: Cardiovascular disease is the dominant cause of death in renal transplant recipients. Left ventricular hypertrophy (LVH) is a known risk factor. After renal transplantation, persistent hypertension is an important determinant for the further evolution of LVH. The aim of the present study was to compare the effect of an angiotensin converting enzyme (ACE) inhibitor (lisinopril) with a calcium channel blocker (CCB) (controlled release nifedipine) in treatment of posttransplant hypertension focusing on changes in LVH. METHODS: One hundred fifty-four renal transplant recipients presenting with hypertension (diastolic BP> or =95 mmHg) during the first 3 weeks after transplantation were randomized to receive double-blind 30 mg nifedipine or 10 mg lisinopril once daily. RESULTS: One hundred twenty-three patients completed 1 year of treatment. Good quality echocardiographic data were available in 116 recipients (62 nifedipine/54 lisinopril) 2 and 12 months posttransplant. Blood pressure was equally well controlled in the two groups throughout the study (mean systolic/diastolic+/-SD after 1 year: 140+/-16/87+/-8 mmHg with nifedipine and 136+/-17/85+/-8 mmHg with lisinopril). Left ventricular mass index was reduced by 15% (P<0.001) in both groups (from 153+/-43 to 131+/-38 g/m2 with nifedipine and from 142+/-35 to 121+/-34 g/m2 with lisinopril). There were no statistically significant differences between the two treatment groups at baseline or at follow-up. CONCLUSIONS: In hypertensive renal transplant recipients with well-controlled blood pressure, there is a regression of left ventricular mass after renal transplantation. The regression of left ventricular mass index is observed to a similar extent in patients treated with lisinopril or nifedipine.


Assuntos
Anti-Hipertensivos/uso terapêutico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Ecocardiografia , Coração/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Hipertensão/etiologia , Transplante de Rim/efeitos adversos , Lisinopril/uso terapêutico , Nifedipino/uso terapêutico , Adulto , Anti-Hipertensivos/efeitos adversos , Bloqueadores dos Canais de Cálcio/administração & dosagem , Bloqueadores dos Canais de Cálcio/efeitos adversos , Ciclosporina/uso terapêutico , Preparações de Ação Retardada , Método Duplo-Cego , Feminino , Coração/fisiopatologia , Ventrículos do Coração , Humanos , Imunossupressores/uso terapêutico , Lisinopril/efeitos adversos , Masculino , Pessoa de Meia-Idade , Nifedipino/administração & dosagem , Nifedipino/efeitos adversos , Estudos Prospectivos , Fatores de Tempo
4.
Am J Cardiol ; 59(9): 975-8, 1987 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-3565287

RESUMO

Doppler echocardiography was used to measure cardiac stroke volume in 10 patients with coronary artery disease who were treated with cardioactive drugs. Stroke volume estimates were determined at the aortic orifice by multiplying area by systolic velocity integral measured both from the suprasternal and the apical approach. Recordings were done independently by 2 experienced observers on the same day and repeated once after 1 to 21 days. Analysis of variance showed that no systematic differences were introduced by the 2 observers and Doppler approaches or by measuring on different days. The coefficient of variation between any pair of measurements in each patient was 9%. This variability is probably a result of the method or spontaneous fluctuations of the stroke volume and not of the varying recording conditions. The ultrasonic method detects day-to-day changes of cardiac stroke volume larger than 20% with a probability greater than 0.95.


Assuntos
Doença das Coronárias/diagnóstico , Ecocardiografia/normas , Volume Sistólico , Adulto , Análise de Variância , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica , Fatores de Tempo
5.
Ann Thorac Surg ; 62(4): 1190-2, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8823114

RESUMO

Atrial septal aneurysms have been recognized as sources of arterial embolism. An intraatrial aneurysm was demonstrated in the fossa ovalis of a 45-year-old woman who suffered an episode of cerebral embolism. The disorder is rarely treated surgically. Most patients with this condition are given life-long anticoagulation, a treatment that may have serious complications. As an alternative treatment with possible lower risk, we removed the aneurysm surgically.


Assuntos
Aneurisma Cardíaco/cirurgia , Aneurisma Intracraniano/etiologia , Procedimentos Cirúrgicos Cardíacos/métodos , Feminino , Aneurisma Cardíaco/complicações , Átrios do Coração/cirurgia , Septos Cardíacos/cirurgia , Humanos , Pessoa de Meia-Idade
6.
Heart ; 75(6): 591-5, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8697163

RESUMO

OBJECTIVE: To assess by echocardiography the occurrence and degree of late cardiac sequelae after treatment for Hodgkin's disease by radiation and chemotherapy. PATIENTS AND METHODS: In Norway from 1980 to 1988, 129 patients < 50 years old with Hodgkin's disease had curative treatment with mediastinal radiation, with or without chemotherapy. 116 (90%) of these patients (mean (SD) age 37 (7) years, 67 males) were examined by echocardiography 5-13 years after treatment. 40 healthy individuals (mean (SD) age 40 (11), 20 males) were examined as controls. All those examined were in regular sinus rhythm. RESULTS: Grade > 1 (scale 0-3) aortic and/or mitral valvar regurgitation was found in 24% of the patients (15% aortic, 7% mitral, and 2% aortic+mitral), affecting 46% of the females v 16% of the males (P < 0.001). Female gender was a significant risk factor for aortic and mitral regurgitation (odds ratio 4.7, 95% confidence interval 2.0 to 11.2), whereas age, period of follow up, radiation dose, and chemotherapy were not. Thickened pericardium was diagnosed in 15% of the patients. No risk factors were identified. No cases of pericardial thickening or valvar regurgitation grade > 1 were recorded in the control group. Mean values for measured and calculated indices of systolic and diastolic function were within the normal range for patients and controls. The patients had reduced E/A ratio compared with the healthy controls (E/A 1.1 v 2.0, P < 0.001). CONCLUSIONS: Abnormal left sided valvar regurgitation was detected in one fourth of the patients, affecting the aortic valve in more than half of the cases. Females had an increased risk of valvar regurgitation. Echocardiographic screening after high-dose mediastinal radiation is recommended.


Assuntos
Doenças das Valvas Cardíacas/etiologia , Doença de Hodgkin/radioterapia , Adulto , Insuficiência da Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/etiologia , Estudos de Coortes , Feminino , Doenças das Valvas Cardíacas/diagnóstico por imagem , Doença de Hodgkin/diagnóstico por imagem , Humanos , Masculino , Mediastino , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/etiologia , Radioterapia/efeitos adversos , Fatores de Risco , Fatores Sexuais , Ultrassonografia
7.
J Am Soc Echocardiogr ; 9(2): 129-34, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8849608

RESUMO

The pulmonary venous flow (PVQ) pattern usually has two antegrade flow waves, corresponding to ventricular systole and diastole, respectively, and is used to assess left atrial pressure. To study the effects of atrioventricular conduction (AVD) and heart rate (HR) on the PVQ pattern, transthoracic pulsed Doppler recordings of pulmonary venous, transmitral, and aortic flow were made in five healthy subjects with dual-chamber pacemakers. Recordings were made at HRs of 80, 100, and 120 beats/min, with AVDs of 75, 150, and 220 msec at each HR. When the AVD was increased, the biphasic PVQ changed to a monophasic pattern in which a single flow wave covered the transition between ventricular diastole and systole. There was a shift of flow from ventricular systole to diastole. When HR was increased, the systolic fraction of the PVQ increased as a result of an increase in the relative duration of systole. In conclusion, AVD and HR influenced the PVQ pattern in subjects without signs of ventricular dysfunction. This may be a limitation to the use of the flow pattern to assess left atrial pressure.


Assuntos
Nó Atrioventricular/fisiopatologia , Frequência Cardíaca , Circulação Pulmonar , Veias Pulmonares/fisiopatologia , Adolescente , Adulto , Análise de Variância , Nó Atrioventricular/diagnóstico por imagem , Ecocardiografia Doppler/instrumentação , Ecocardiografia Doppler/métodos , Ecocardiografia Doppler/estatística & dados numéricos , Feminino , Bloqueio Cardíaco/diagnóstico por imagem , Bloqueio Cardíaco/fisiopatologia , Bloqueio Cardíaco/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Marca-Passo Artificial , Veias Pulmonares/diagnóstico por imagem , Síndrome do Nó Sinusal/diagnóstico por imagem , Síndrome do Nó Sinusal/fisiopatologia , Síndrome do Nó Sinusal/terapia , Volume Sistólico
8.
J Am Soc Echocardiogr ; 8(3): 270-9, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7640020

RESUMO

The aim of the study was to investigate the effect of acute myocardial ischemia on the early diastolic mitral-to-apical velocity profile. Intraventricular filling velocities were measured by color M-mode Doppler echocardiography, which allows simultaneous measurements of velocities at multiple sites. Twenty patients were examined during angioplasty and eight dogs during transient coronary artery occlusion. Velocities at each 0.46 cm level from the mitral tip toward the apex were determined at the time of peak early transmitral velocity. Before angioplasty, early diastolic flow velocities decreased progressively from the mitral tip toward the apex. During angioplasty, intraventricular velocities showed a more abrupt decrease from the middle region toward the apex (p < 0.05). A similar change in the mitral-to-apical profile was found during myocardial ischemia in dogs (p < 0.05). Also, there was a decrease in peak early transmitral velocity (p < 0.01) and peak early transmitral pressure gradient (p = 0.06). Volume loading and constriction of the caval veins performed in the nonischemic ventricle did not appear to change the mitral-to-apical velocity profile. Regional myocardial ischemia was associated with a change in the mitral-to-apical velocity profile as measured by color M-mode Doppler echocardiography. The altered filling pattern could not be explained by changes in loading conditions and may reflect impaired relaxation of the ischemic ventricle.


Assuntos
Doença das Coronárias/diagnóstico por imagem , Ecocardiografia Doppler em Cores , Ecocardiografia , Isquemia Miocárdica/diagnóstico por imagem , Angioplastia Coronária com Balão , Animais , Velocidade do Fluxo Sanguíneo/fisiologia , Circulação Coronária/fisiologia , Doença das Coronárias/fisiopatologia , Doença das Coronárias/terapia , Diástole/fisiologia , Cães , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/fisiopatologia , Reprodutibilidade dos Testes
9.
J Am Soc Echocardiogr ; 12(10): 801-10, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10511648

RESUMO

BACKGROUND: Myocardial infarction induces left ventricular (LV) wall motion abnormalities during isovolumic relaxation (IVR) and may potentially alter intraventricular flow during this period. This study evaluated whether 2-dimensional color Doppler measurements of intraventricular flow during IVR were able to identify LV dysfunction caused by coronary artery disease. METHODS: Patients with single-vessel coronary artery disease and posterior wall infarction (21 patients) or anterior wall infarction (27 patients) were included. Eighteen healthy persons served as a control group. LV function was examined by 2-dimensional echocardiography, 2-dimensional color Doppler, and pulsed Doppler techniques. RESULTS: All normal persons (23.6 +/- 10.9 cm/s) and patients with posterior infarction (19.6 +/- 9.3 cm/s) had flow propagation towards LV apex during IVR. Patients with anterior wall infarction had reversed flow direction (-12.2 +/- 8.7 cm/s, P <.001). The echocardiographic wall motion score index of the 4 apical segments correlated well with flow velocities (r = -0.78, P <.001). CONCLUSION: Reversed flow propagation during IVR may become a sensitive clinical marker of regional ischemia.


Assuntos
Contração Miocárdica , Infarto do Miocárdio/fisiopatologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia , Análise de Variância , Velocidade do Fluxo Sanguíneo , Estudos de Casos e Controles , Angiografia Coronária , Circulação Coronária , Doença das Coronárias/fisiopatologia , Diástole/fisiologia , Ecocardiografia Doppler em Cores , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sístole/fisiologia
10.
J Am Soc Echocardiogr ; 12(6): 500-7, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10359922

RESUMO

OBJECTIVES: This study sought to clarify the diastolic flow pattern in the normal left ventricle. BACKGROUND: During left ventricular filling, basally directed (retrograde) velocities are seen in the outflow compartment. These velocities may represent blood returned from the apical region or a shortcut at a more basal level. METHODS: Left ventricular flow patterns were identified in 18 healthy individuals (age 47 +/- 12 years) with the use of high frame-rate two-dimensional color Doppler and color M-mode Doppler echocardiography techniques. Intraventricular velocities were measured with single pulsed Doppler at 3 levels in both inflow and outflow compartments (posterolateral and anteroseptal parts of the left ventricle). RESULTS: During early transmitral flow acceleration, all intraventricular velocities were directed towards the apex. However, after peak early and late inflow velocities and during diastasis, retrograde velocities were identified in the outflow compartment. These retrograde velocities occurred earlier, and were higher, at the level of the deflected anterior mitral leaflet tip compared with more apical levels (P <.001). A velocity pattern was established, consistent with early intraventricular vortex formation behind both mitral leaflets. The vortex adjacent to the anterior leaflet subsequently enlarged to include a major part of the left ventricle. CONCLUSION: Uniform diastolic flow patterns were identified in the normal left ventricles. The findings suggest that both early and late diastolic filling start with an initial motion of a fluid column, succeeded by vortex formation, which explains retrograde flow in the outflow compartment.


Assuntos
Velocidade do Fluxo Sanguíneo , Diástole/fisiologia , Ecocardiografia Doppler em Cores , Ventrículos do Coração/diagnóstico por imagem , Função Ventricular Esquerda/fisiologia , Adulto , Análise de Variância , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Reprodutibilidade dos Testes , Processamento de Sinais Assistido por Computador
11.
J Am Soc Echocardiogr ; 13(11): 986-94, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11093100

RESUMO

BACKGROUND AND OBJECTIVE: Tissue Doppler echocardiography (TDE) is a promising method for the assessment of regional myocardial function, but pulsed TDE does not provide quantitative data from multiple regions simultaneously. This feature is important for the objective assessment of regional differences in myocardial function. In the present study, we investigated a new off-line TDE method that provides quantitative pulsed velocity data from an unlimited number of regions selected within a 2-dimensional (2D) image. The goal of the study was to determine the ability of this new approach to quantify regional myocardial function during acute myocardial ischemia induced by balloon angioplasty. METHODS: Twenty-two patients undergoing angioplasty of the left anterior descending coronary artery (LAD) were studied. Left ventricular longitudinal wall motion was assessed by 2D TDE from the apical 4-chamber view before, during, and after angioplasty. Images were sampled at a rate of 69 +/- 15 frames/s, and the off-line analysis allowed simultaneous measurement of velocities in multiple myocardial segments. RESULTS: There were 3 major alterations in the systolic velocity pattern during LAD occlusion. Peak early systolic velocities along the apical septum were significantly reduced during LAD occlusion (2.8 +/- 1.2 cm/s to 0.6 +/- 1.7 cm/s, P <.001). Myocardial velocities in mid systole suggested paradoxical wall motion (1.0 +/- 1.2 cm/s to -0.8 +/- 0.9 cm/s, P <.001). When comparing the ischemic regions of the left ventricle with the nonischemic regions, each patient demonstrated lower myocardial systolic velocities in the ischemic region. Furthermore, during early diastole, the wall motion of the ischemic segments showed a postsystolic contraction pattern with velocities changing from -0.9 +/- 1.0 cm/s to 1.9 +/- 1.3 cm/s (P <.001). CONCLUSION: This new 2D TDE approach is able to quantify detailed myocardial velocity profiles from multiple regions simultaneously. Single-beat comparisons of ischemic and nonischemic regions might enhance the sensitivity for diagnosing ischemic heart disease. Reversed systolic wall motion during midsystole and marked positive velocity during early diastole might be new and important markers of myocardial wall ischemia.


Assuntos
Ecocardiografia Doppler de Pulso/métodos , Contração Miocárdica , Isquemia Miocárdica/diagnóstico por imagem , Disfunção Ventricular Esquerda/diagnóstico por imagem , Idoso , Angioplastia Coronária com Balão , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
12.
Int J Cardiol ; 47(2): 169-75, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7721486

RESUMO

We investigated the measurement repeatability of four pulmonary venous flow indices. The indices were measured on 45 anonymised, transthoracic Doppler recordings of adequate technical quality. Measurements were taken by two independent observers, and repeated after 10 days. Plus/minus the repeatability coefficient, which was used to quantify repeatability, gives the 95% probability limits for random variation between repeated measurements. The index D-diff, which is the difference in duration of the pulmonary venous flow reversal during atrial systole and the transmitral A-wave, had repeatability coefficients of 50 and 57 ms intra- and inter-observer. For the fraction of antegrade pulmonary venous flow during ventricular systole, the coefficients were 12 and 13 percentage points, but improved to 6 and 7 among the high-quality recordings. The retrograde pulmonary venous flow during atrial systole as a fraction of the antegrade flow, had coefficients of 5 percentage points both intra- and inter-observer. The coefficient for the peak velocity of retrograde pulmonary venous flow was 0.05 m/s intra- and inter-observer. Thus, the systolic fraction was the only index that showed a satisfactory repeatability. We suggest that if the other indices are used, measurements should be taken by a blinded observer to avoid observer bias.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Circulação Pulmonar/fisiologia , Veias Pulmonares/fisiologia , Análise de Variância , Ecocardiografia Doppler de Pulso/estatística & dados numéricos , Humanos , Variações Dependentes do Observador , Veias Pulmonares/diagnóstico por imagem , Pressão Propulsora Pulmonar , Volume Sistólico
13.
Int J Cardiol ; 10(3): 192-212, 1986 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3957467

RESUMO

The present study was designed to develop a new Doppler method to estimate noninvasively the peak-to-peak pressure gradient in patients with aortic stenosis. It was carried out in two steps. In the first study, left heart catheterization data were analysed in 58 patients with aortic stenosis. The peak pressure gradient correlated highly with (r = 0.98) but overestimated significantly the peak-to-peak pressure gradient. The averaged pressure gradient (average of the peak gradient and the gradient at the peak aortic pressure) was found to approximate closely the peak-to-peak pressure gradient (r = 0.99) with a good separation between significant and insignificant aortic stenosis. The ratio of the left ventricular ejection time over the aortic pressure descending time was studied and the beginning of the late one-third systole was chosen as the point for determining the late systolic gradient by the Doppler technique. In the second study, Doppler echocardiography and cardiac catheterization were performed in 35 patients with aortic stenosis. The Doppler-determined peak pressure gradient correlated highly with catheterization-measured peak pressure gradient (r = 0.95) but overestimated significantly the peak-to-peak pressure gradient. The Doppler-determined averaged pressure gradient (average of the peak and the late systolic gradients) estimated accurately the peak-to-peak gradient (r = 0.97) with a good separation between significant and insignificant aortic stenosis. These results demonstrate the limitations of the peak pressure gradient measurement and the reliability of the Doppler-determined averaged pressure gradient for estimation of the peak-to-peak pressure gradient.


Assuntos
Estenose da Valva Aórtica/diagnóstico , Pressão Sanguínea , Ecocardiografia/métodos , Adolescente , Adulto , Idoso , Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/fisiopatologia , Cateterismo Cardíaco , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica
14.
Int J Cardiol ; 26(3): 349-54; discussion 355-9, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2312203

RESUMO

Interobserver variability in echocardiographic estimates of the area of stenosed aortic valves was assessed in 30 consecutive patients. Using the continuity equation, two independent observers calculated the area of stenosis from separate recordings of the diameter of the aortic orifice and the velocity time integral in the left ventricular outflow tract and in the stenotic jet. No significant difference between the observers was noted for any measurement. With respect to the area of stenosis, a high correlation between the observers was found (r = 0.92, P less than 0.001) and the regression line was close to the line of identity. The 95% limits of agreement were less than +/- 0.3 cm2. No discrepancy between the observers was found in the assessment of cases for aortic stenosis less than 0.8 cm2. Regression analyses showed good interobserver agreement also for the diameter of the orifice, the velocity time integrals, and the mean pressure gradient (r greater than 0.90, P less than 0.001). The greatest variability was noted for the diameter of the aortic orifice (95% limits of agreement +/- 1.4 cm2). We conclude that echocardiography enables reproducible estimates of the orificial area of stenosed aortic valves. Changes greater than 0.3 cm2 can be detected with a confidence probability of 95%. The greatest source of error is the measurement of the diameter of the outflow tract at the basal attachments of the aortic leaflets.


Assuntos
Estenose da Valva Aórtica/patologia , Ecocardiografia Doppler/estatística & dados numéricos , Ecocardiografia/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Aorta/patologia , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea , Débito Cardíaco , Feminino , Ventrículos do Coração , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Cardiovasculares , Variações Dependentes do Observador , Reprodutibilidade dos Testes
15.
Int J Cardiol ; 48(1): 89-95, 1995 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-7744542

RESUMO

We correlated the new diastolic index 'delay of apical peak velocity', as measured by colour M-mode Doppler, with radionuclide ventriculographic indices of ventricular function. Thirty-seven patients with coronary artery disease participated in the prospective and blinded study, which included repeated acquisitions to determine the effect of realigning the Doppler sample beam. In multiple regression, neither peak filling rate, left ventricular phase histogram width nor ejection fraction were statistically significantly related to delay of apical peak velocity. The standard deviation of the differences between duplicate colour M-mode acquisitions corresponded to half the reference range of the index. We conclude that in this blinded investigation, the new Doppler index did not provide information about ventricular function equivalent to radionuclide ventriculography. The index may be significantly influenced by sample beam position.


Assuntos
Doença das Coronárias/diagnóstico por imagem , Ecocardiografia Doppler em Cores , Imagem do Acúmulo Cardíaco de Comporta , Idoso , Velocidade do Fluxo Sanguíneo/fisiologia , Doença das Coronárias/fisiopatologia , Diástole , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia
16.
Int J Cardiol ; 43(1): 79-85, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8175223

RESUMO

We investigated the repeatability of two recently reported colour M-mode Doppler measures of left ventricular diastolic function. 'Delay of peak velocity' is the time interval from peak velocity of early filling at the mitral tip level to peak velocity in the apical region. The 'velocity of flow propagation' is the speed of the mitral to apical spread of the early diastolic filling. Two examiners independently and blindly made measurements by both methods on 32 digital recordings twice, using custom software. Inter- and intra-observer repeatability were given in terms of limits of agreement, where 1 denotes perfect agreement. Limits of intra-observer agreement were 0.72-1.43 for measurements of 'delay of peak velocity', and 0.39-2.28 for 'velocity of flow propagation'. Limits of inter-observer agreement were 0.68-1.42 and 0.19-2.04 respectively. The correlation between the methods was weak (r = 0.45), suggesting that they may detect different properties of early diastole. We suggest that the reliability of the methods may be improved by replicate measurements performed blindly. There are reasons to express the velocity of flow propagation on a logarithmic scale.


Assuntos
Ecocardiografia Doppler/normas , Função Ventricular Esquerda/fisiologia , Humanos , Variações Dependentes do Observador , Reprodutibilidade dos Testes
17.
J Heart Valve Dis ; 6(2): 115-22, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9130117

RESUMO

BACKGROUND AND AIMS OF THE STUDY: The hemodynamic function of the CarboMedics bileaflet mitral valve prosthesis was evaluated by Doppler echocardiography and by heart catheterization. The clinical state of the invasively examined patients was evaluated before and after surgery. METHODS: Doppler echocardiography was performed in 54 patients at six months after surgery. Further, combined right and left heart catheterization was performed in 22 of these patients before surgery and at six months thereafter. RESULTS: The Doppler mean gradients were small (3.6 +/- 1.2 mmHg), and corresponded well with Doppler mean gradients in the subgroup examined with both methods (3.5 +/- 1.1 mmHg) and with the invasive gradients (3.4 +/- 1.9 mmHg); there was also no difference between the different valve sizes. Clinically, pressure recovery distal to the valve is probably so small that no systematic difference between the two techniques of measurement is present. Only physiological regurgitation was found, and no case of valve dysfunction. The patients improved from functional NYHA class 3.1 +/- 0.4 to 1.4 +/- 0.6, regardless of preoperative diagnosis, with most pronounced improvement in those with mitral stenosis. Pulmonary artery pressure was normalized. Pulmonary vascular resistance and cardiac index improved slightly. CONCLUSIONS: In conclusion, the valvular prostheses demonstrated excellent hemodynamic function. There was striking agreement between the small invasive and non-invasive gradients. Finally, the functional status of the patients improved considerably, most distinctly in those patients with prior mitral stenosis.


Assuntos
Bioprótese , Doenças das Valvas Cardíacas/fisiopatologia , Doenças das Valvas Cardíacas/cirurgia , Próteses Valvulares Cardíacas/instrumentação , Valva Mitral/cirurgia , Complicações Pós-Operatórias/diagnóstico por imagem , Adulto , Idoso , Velocidade do Fluxo Sanguíneo , Cateterismo Cardíaco , Ecocardiografia Doppler , Segurança de Equipamentos , Estudos de Avaliação como Assunto , Feminino , Seguimentos , Doenças das Valvas Cardíacas/diagnóstico , Próteses Valvulares Cardíacas/métodos , Hemodinâmica/fisiologia , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/fisiopatologia , Resultado do Tratamento
18.
Clin Cardiol ; 20(11): 957-62, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9383590

RESUMO

BACKGROUND: The reproducibility of left ventricular (LV) mass measurement by two-dimensional (2-D) echocardiography is inadequate for individual assessments. HYPOTHESIS: This study was undertaken to evaluate the potential of LV mass determination with a new three-dimensional (3-D) echocardiographic method compared with 2-D measurements. METHODS: Porcine agarose-filled left ventricles (n = 15, true mass 61-511 g) of different shapes were measured by a multiplane 3-D method based on 90 images acquired by probe rotation axis (1) perpendicular and (2) parallel to the ventricular long axis ["parasternal" (the left sternal border was not present as a reference point in this study) and apical views]. Mass was also obtained using (3) the biplane truncated ellipsoid and (4) area-length methods, as well as (5) the modified cube formula. Five hearts were not analyzed with the apical 3-D technique because of insufficient image quality. RESULTS: Systematic deviation from true mass was small with all methods (< 5.3%). Accuracy, expressed as 1 standard deviation of individual estimates around this systematic bias, was 7.7, 13.6, 8.2, 11.9, and 11.9% of true mass for the methods 1-5, respectively. Interobserver reproducibility, expressed as the coefficient of variation, was 4.7, 8.8, 8.1, 8.9, and 9.4% for the same methods. CONCLUSION: Limits for individual accuracy and reproducibility of LV mass estimates are nearly doubled using apical compared with "parasternal" 3-D echocardiography in vitro. A main advantage of "parasternal" 3-D compared with 2-D LV mass estimates is better reproducibility, but at the expense of greater time consumption. Apical 3-D technique is not superior to simpler 2-D methods based on "parasternal" short axis imaging.


Assuntos
Ecocardiografia Tridimensional/métodos , Ventrículos do Coração/diagnóstico por imagem , Aumento da Imagem , Animais , Ecocardiografia , Estudos de Avaliação como Assunto , Suínos
19.
Acta Paediatr Suppl ; 413: 39-43, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8783771

RESUMO

The cardiac findings in eight patients, two of whom were female, with total lipodystrophy (Berardinelli-Seip's disease) are reported. One of them had the acquired form of the disease. Four patients died at a mean age of 32 years. As far as we know, at least three of them most likely died for cardiac reasons, one shortly after recovering from an attempted suicide. All eight patients had hypertrophic hearts, mostly with deranged diastolic, but also systolic, function. One had pulmonary hypertension. We conclude that generalized lipodystrophy is a serious disease with cardiac affection leading to cardiac dysfunction and early death. There is no specific cardiac treatment, and the treatment should be according to the general guidelines for patients with hypertrophic, dysfunctioning hearts.


Assuntos
Cardiopatias/etiologia , Lipodistrofia/complicações , Adulto , Cardiomegalia/etiologia , Evolução Fatal , Feminino , Cardiopatias/diagnóstico , Humanos , Hipertensão Pulmonar/etiologia , Masculino , Estudos Retrospectivos
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