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1.
Ann Cardiol Angeiol (Paris) ; 53(4): 188-92, 2004 Jul.
Artigo em Francês | MEDLINE | ID: mdl-15369314

RESUMO

Heart failure is associated with modifications of skeletal muscle cells, which could participate in the exercise limitation of the patients. However, the mechanical efficiency of the skeletal muscle has not been fully evaluated in these patients. We therefore measured VO2 during prolonged exercise (15 min) at constant load to obtain stable conditions. Load was chosen after maximal stress test as 35% and 65% of load at anaerobic threshold. VO2 during assisted cycling was subtracted from that during constant load to evaluate the relationship between VO2 and Watt. Twenty CHF patients (peak VO2 17.6 ml/kg/min, LVEF <35%) have been compared to 11 controls (peak VO2 40.2 ml/ml/kg). VO2 was similar in the two groups at rest and during assisted cycling. Ventilation on contrary was higher in CHF patients. The relationship between VO2 and Watt was similar in the two populations, indicating that skeletal muscle mechanical efficiency was not altered in CHF patients. In conclusion, histological modifications present in skeletal muscle of CHF patients do not translate into altered skeletal muscle efficiency.


Assuntos
Metabolismo Energético , Insuficiência Cardíaca/metabolismo , Músculo Esquelético/metabolismo , Adulto , Doença Crônica , Teste de Esforço/métodos , Humanos , Pessoa de Meia-Idade
2.
Arch Mal Coeur Vaiss ; 93(2): 185-7, 2000 Feb.
Artigo em Francês | MEDLINE | ID: mdl-10830095

RESUMO

A 31 year old woman with Marfan's syndrome had a dilatation of the aortic root (55-60 mm at the beginning of pregnancy). Pregnancy was continued with beta-blocker therapy and with regular echocardiographic follow-up. The aortic dilatation increased (62-65 mm) at the last control and, at the 34th week of pregnancy, the patient suffered a dissection of the ascending aorta. A caesarean section was performed with a Bentall procedure during the same operative session. The mother and baby girl are well two years later. The problems of pregnancy in patients with Marfan's syndrome are discussed.


Assuntos
Aneurisma Aórtico/cirurgia , Dissecção Aórtica/cirurgia , Síndrome de Marfan/complicações , Complicações Cardiovasculares na Gravidez/cirurgia , Antagonistas Adrenérgicos beta/uso terapêutico , Adulto , Dissecção Aórtica/patologia , Aneurisma Aórtico/patologia , Cesárea , Feminino , Humanos , Gravidez , Resultado da Gravidez , Resultado do Tratamento
4.
Eur J Echocardiogr ; 1(1): 66-71, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12086218

RESUMO

AIMS: We evaluated echo-guided pericardiocentesis with contrast study in cardiac tamponade management. PATIENTS AND METHODS: From 1982 to 1998 we performed pericardiocentesis in 110 patients (56 +/- 14 years old). Subxiphoid approach was used in 109. Cardiac tamponade was idiopathic (n = 16), secondary to malignant disease (n = 50) and miscellaneous disorders (n = 44). RESULTS: Pericardial fluid was bloody (n=75), serous (n = 29) or turbid (n = 6). Mean volume of fluid removed was 585 +/- 370 ml. When prolonged drainage (60 +/- 26 h) was used (n = 41), total effusion volume was 850 +/- 340 ml. Eleven deaths were observed during the early period following pericardiocentesis. No relation with procedure was demonstrated by autopsy in 10, and death always occurred in critically-ill patients (five malignant diseases, five cardiac ruptures and one septic shock). Other complications were: right ventricular puncture (n = 11) with deleterious effect in one, vasovagal hypotension (n = 6) and paroxysmal arrhythmia (n = 6). Surgical drainage was mandatory in 19 patients. It had to be done as an emergency (within 6 h), because of failure of the procedure in four patients. In 14 patients without prolonged drainage a delayed surgical evacuation was indicated, because of persistent (n = 3) or recurrent (n = 11) cardiac tamponade. Only one surgical procedure was required after prolonged drainage. CONCLUSIONS: Echo-guided pericardiocentesis with contrast study is an effective technique which reduces the risk of cardiac tamponade management. It should be considered in patients with critical haemodynamic condition or advanced malignancy, and in patients with poor short-term prognosis.


Assuntos
Tamponamento Cardíaco/cirurgia , Ecocardiografia/métodos , Pericardiocentese/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Agulhas
5.
Chest ; 116(5): 1354-9, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10559099

RESUMO

STUDY OBJECTIVE: To investigate the rate of recovery from septic shock in patients with suspected left ventricular (LV) preload deficiency and LV systolic dysfunction. DESIGN: A monitoring period was defined by the need for inotropic/vasopressor support, and LV function was assessed daily during this period by bedside two-dimensional echocardiography (2D-ECHO). SETTING: University hospital ICU. PATIENTS: During a 5-year period, 90 patients with an episode of septic shock (60% with gram-positive bacteria as the causative agent) were consecutively enrolled in the study (mean age, 55 +/- 18 years). Standard volume resuscitation combined with inotropic/vasopressor support was used to maintain systolic arterial pressure > 90 mm Hg. All patients received mechanical ventilation because of associated respiratory failure. The average duration of hemodynamic support was 4.4 +/- 1.6 days. Thirty-four patients were weaned from hemodynamic support during the monitoring period and ultimately recovered (group I). Twenty-eight patients died from refractory circulatory failure during the monitoring period, and 28 died later from ARDS or multiple organ dysfunction syndrome, leading to a 62% overall mortality rate (group II). METHODS: Daily bedside LV volumes and ejection fraction (LVEF) were recorded using 2D-ECHO. Data obtained at the start (day 1 and day 2) and end of the monitoring period (day n) were compared. RESULTS: LV end-diastolic volume was within the normal range of our laboratory values in all patients, but was initially smaller in group II than in group I, and remained so despite fluid loading. LVEF was significantly depressed in all patients, resulting in severe reduction in LV stroke volume (LVSV), which was initially more marked in group I. In group I patients, LVEF significantly improved during the monitoring period, resulting in an increase in LVSV. CONCLUSION: 2D-ECHO changes during hemodynamic support in 90 septic patients confirmed defective LV preload with a propensity to worsen despite fluid loading in nonsurvivors (62% in the present study). Our results are also in agreement with previous studies reporting depressed LV systolic function at the initial phase of septic shock. Since LV dysfunction was more marked in patients who recovered, we suggest that the exact significance of this finding should be reevaluated.


Assuntos
Ecocardiografia , Hidratação , Infecções por Bactérias Gram-Negativas/fisiopatologia , Infecções por Bactérias Gram-Positivas/fisiopatologia , Ventrículos do Coração/diagnóstico por imagem , Choque Séptico/fisiopatologia , Disfunção Ventricular Esquerda/fisiopatologia , Adulto , Volume Cardíaco , Feminino , Seguimentos , Infecções por Bactérias Gram-Negativas/diagnóstico por imagem , Infecções por Bactérias Gram-Negativas/mortalidade , Infecções por Bactérias Gram-Negativas/terapia , Infecções por Bactérias Gram-Positivas/diagnóstico por imagem , Infecções por Bactérias Gram-Positivas/mortalidade , Infecções por Bactérias Gram-Positivas/terapia , Ventrículos do Coração/fisiopatologia , Hospitais Universitários , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Contração Miocárdica , Ressuscitação/métodos , Estudos Retrospectivos , Choque Séptico/diagnóstico por imagem , Choque Séptico/mortalidade , Choque Séptico/terapia , Volume Sistólico , Taxa de Sobrevida , Resultado do Tratamento , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/mortalidade
6.
Can J Anaesth ; 46(5 Pt 1): 423-8, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10349920

RESUMO

PURPOSE: To compare the hemodynamic effects of medical antishock trousers (MAST) inflation in mechanically ventilated patients with normal and poor left ventricular function. METHODS: Twelve patients requiring respiratory support were divided into two groups according to baseline transesophageal echocardiography (TEE) measurements: normal left ventricular dimensions and fractional area of contraction (FAC=61 +/- 5%) (n=7) and dilated cardiomyopathy with reduced FAC (21 +/- 1%) (n=5). All patients were studied when two successive levels of load (mild load by inflation of the leg compartment of MAST at 50 cmH2O and high load by adding the abdominal compartment of MAST inflated at 30 cmH2O) were applied. Global left ventricular systolic function was assessed on the TEE transgastric short-axis view. End-systolic wall stress (ESWS) was used as an indicator of left ventricular afterload. RESULTS: Total respiratory, lung and chest wall compliances were reduced by 48%, 51% and 27% respectively at the high load level (P < 0.05). Whereas no hemodynamic changes occurred at mild load, the high load level produced an increase in left ventricular afterload as evidenced by concomitant increases in diastolic arterial blood pressure (66 +/- 6 to 79 +/- 6 mmHg, P < 0.05) and ESWS (69 +/- 12 to 74 +/- 12 Kdyn x cm(-2) x m(-2), P < 0.05). In patients with dilated cardiomyopathy, this increase in afterload impaired the left ventricular systolic function and end-systolic area increased (19.0 +/- 2.5 to 21.4 +/- 2.9 cm2 x m(-2), P < 0.05) while FAC decreased (22 +/- 2 to 16 +/- 2%, P < 0.05). Left ventricular end-diastolic area remained unchanged during the study in both groups. CONCLUSION: MAST inflation impairs respiratory mechanics and global left ventricular systolic function in cardiac patients without changes in left ventricular preload.


Assuntos
Trajes Gravitacionais , Hemodinâmica , Respiração Artificial , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
Circulation ; 99(20): 2677-81, 1999 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-10338462

RESUMO

BACKGROUND: In patients with Marfan syndrome (MFS), brachial pulse pressure (PP) has been recognized as a risk factor for aortic dilatation, leading to aortic dissection, the main cause of premature death. However, the relationships between aortic PP, aortic stiffness, and aortic root dilation have not been investigated. Our main objective was to determine whether central PP, which takes into account wave reflections and aortic stiffness, is a better determinant of ascending aorta diameter than brachial PP in MFS patients. METHODS AND RESULTS: Twenty patients with confirmed MFS and 20 age- and sex-matched control subjects were included in this cross-sectional, noninvasive study. Elastic properties of the abdominal aorta and common carotid, common femoral, and radial arteries were calculated from the pulsatile changes in arterial diameter and pressure. The ascending aorta diameter, measured with conventional echocardiography, was 37% larger in MFS than in control subjects (P<0.001). Arterial distensibility was 38% lower in MFS than in control subjects at the site of the abdominal aorta (P<0.01) but not at other sites (common carotid, common femoral, and radial arteries). Independently of age and body surface area, ascending aorta diameter was positively correlated with carotid PP in MFS (P<0. 01) and negatively in control subjects (P<0.01) but was not correlated with brachial PP and mean blood pressure. CONCLUSIONS: In patients with MFS, local PP, estimated from carotid PP, was a major determinant of ascending aorta diameter, whereas brachial PP was not. Increased arterial stiffness was confined to the aorta.


Assuntos
Aorta/fisiopatologia , Pressão Sanguínea/fisiologia , Síndrome de Marfan/fisiopatologia , Pulso Arterial , Vasodilatação/fisiologia , Adulto , Artérias/fisiopatologia , Artérias Carótidas/fisiopatologia , Ecocardiografia , Feminino , Coração/fisiopatologia , Humanos , Masculino , Síndrome de Marfan/diagnóstico por imagem , Pessoa de Meia-Idade , Artéria Radial/fisiopatologia
9.
Presse Med ; 27(12): 567-70, 1998 Mar 28.
Artigo em Francês | MEDLINE | ID: mdl-9767949

RESUMO

BACKGROUND: Left ventricular failure has been described following surgery due to localized compression of the left ventricle and in case of diastolic left ventricular dysfunction after pericardiotomy or pericardiocentesis. CASE REPORTS: Global heart failure was observed in 3 patients with dilated cardiopathy who developed tamponade. Systolic left ventricular dysfunction was caused by ischemic heart disease in one patient and secondary to anthracyclin chemotherapy in the two others. The effusion was successfully removed with pericardiocentesis in all three cases. No specific complications were observed. DISCUSSION: Although exceptional, tamponade may occur in patients with signs of left ventricular failure.


Assuntos
Tamponamento Cardíaco/complicações , Disfunção Ventricular Esquerda/etiologia , Adulto , Idoso , Antibióticos Antineoplásicos/efeitos adversos , Baixo Débito Cardíaco/etiologia , Tamponamento Cardíaco/cirurgia , Cardiomiopatia Dilatada/complicações , Cardiomiopatia Dilatada/cirurgia , Ecocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/complicações , Paracentese/efeitos adversos , Pericardiectomia/efeitos adversos , Sístole , Disfunção Ventricular Esquerda/diagnóstico por imagem
10.
Chest ; 114(2): 556-62, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9726745

RESUMO

STUDY OBJECTIVES: Positive end-expiratory pressure (PEEP) has been proposed to improve cardiac output in patients with left ventricular (LV) dysfunction. This study was designed to compare quantitative global and regional LV performance in response to PEEP in patients with normal and poor LV function. DESIGN: A prospective clinical trial. SETTING: Adult medical ICU in a university hospital. PATIENTS: Twelve critically ill patients requiring respiratory support and divided into two groups according to baseline transesophageal echocardiographic (TEE) measurements: normal LV dimensions and fractional area of contraction (FAC=61+/-5%) (n=7) and dilated cardiomyopathy with reduced FAC (21+/-1%) (n=5). MEASUREMENTS AND RESULTS: All patients were studied when two successive levels of PEEP (best PEEP as the highest value of respiratory compliance and high PEEP as best PEEP+10 cm H2O) were applied. Global systolic LV performance and quantitative regional wall motion analysis performed by the centerline method were assessed on the TEE transgastric short-axis view. End-systolic wall stress (ESWS) was used as a reliable indication of LV afterload. PEEP reduced LV dimensions asymmetrically in both groups of patients and septolateral diameter significantly decreased without affecting global LV systolic performance. Additionally, high PEEP produced a significant impairment in septal kinetics as evidenced by the centerline method. High PEEP also decreased ESWS for all patients (-27% in normal group and -23% in cardiac group, p<0.05) without significant improvement in global systolic LV performance (FAC: +2% in normal group and +0% in cardiac group; not significant). CONCLUSIONS: PEEP cannot be recommended routinely to improve LV performance in patients with severe dilated cardiomyopathy.


Assuntos
Cardiomiopatia Dilatada/complicações , Ecocardiografia Transesofagiana , Respiração com Pressão Positiva , Disfunção Ventricular Esquerda/terapia , Função Ventricular Esquerda/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Débito Cardíaco , Feminino , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica , Estudos Prospectivos , Testes de Função Respiratória , Resultado do Tratamento , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/fisiopatologia
11.
Arch Mal Coeur Vaiss ; 91(7): 843-8, 1998 Jul.
Artigo em Francês | MEDLINE | ID: mdl-9749175

RESUMO

Transoesophageal echocardiography is a method of visualising intracardiac thrombi and could therefore be useful for the diagnosis of pulmonary embolism, but its diagnostic value is unknown. The authors carried out a prospective study with this diagnostic tool in massive pulmonary embolism. The study protocol was to perform transthoracic echocardiography in patients with suspected acute pulmonary embolism and then to perform transoesophageal echocardiography when there were signs of acute cor pulmonale. The results of both echocardiographic investigations were compared with two reference radiological techniques: the spiral CT scan and/or pulmonary angiography. Fifty-six patients underwent transthoracic echocardiography. In the 34 patients with transthoracic echocardiographic signs of acute cor pulmonale, the positive predictive value of the investigation for pulmonary embolism was 91% and the negative predictive value was 54%. Twenty of these 34 patients underwent transoesophageal echocardiography. The sensitivity and specificity for the diagnosis of proximal embolism were 85% and 86% respectively. The limitations of the method were poor visualisation of the left pulmonary artery in which only one thrombus was detected, compared with 6 by spiral CT scan, and the absence of visualisation of lobar arteries. Consequently, the real sensitivity of transoesophageal echocardiography for visualisation of all thrombi in the pulmonary arteries in acute cor pulmonale was only 55%. In acute cor pulmonale, the diagnostic value of transoesophageal echocardiography is poor because the sensitivity for visualisation of intra-pulmonary arterial thrombi is low compared with other radiological techniques. However, in patients with proximal emboli in the right or main pulmonary artery, the diagnosis may be established in a few minutes without the need of other more invasive techniques. Nevertheless, normal transoesophageal echocardiography does not rule out the presence of proximal in the left pulmonary artery or distal emboli in the lobar arteries.


Assuntos
Ecocardiografia Transesofagiana , Embolia Pulmonar/diagnóstico por imagem , Doença Cardiopulmonar/diagnóstico por imagem , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia , Artérias/diagnóstico por imagem , Ecocardiografia , Feminino , Cardiopatias/diagnóstico por imagem , Humanos , Pulmão/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Artéria Pulmonar/diagnóstico por imagem , Sensibilidade e Especificidade , Trombose/diagnóstico por imagem , Tomografia Computadorizada por Raios X
12.
Arch Mal Coeur Vaiss ; 91(1): 13-20, 1998 Jan.
Artigo em Francês | MEDLINE | ID: mdl-9749259

RESUMO

Between April 1982 and December 1995, 78 consecutive patients with an average age of 57 +/- 13 years underwent echo-guided pericardiocentesis in the intensive care unit for poorly tolerated pericardial effusions. The patients were admitted to the cardiology departments of Ambroise-Paré Hospital at Boulogne (n = 44). Gilles-de-Corbeil Hospital at Corbeil-Essonnes (n = 31) and Val-de-Grâce Hospital in Paris (n = 3). The underlying aetiologies were malignant disease (n = 31), idiopathic (n = 13), post-surgery (n = 7), infection (n = 7), autoimmune (n = 6), post-radiotherapy (n = 6), post-myocardial infarction (n = 3), chronic renal failure (n = 3) and coagulation defects (n = 2). Pericardial puncture was undertaken by the subxiphoid (n = 77) or left parasternal (n = 1) approaches under guidance of echocardiography. Intra-pericardial contrast was used to verify the position of the catheter. The average volume of liquid drained was 580 +/- 390 mL. After pericardiocentesis, continuous drainage was continued in 17 patients for an average duration of 63 +/- 29 hours. The total average volume was 750 +/- 330 mL. The major complications were a) three deaths during the puncture, not caused by the procedure after post-mortem study, b) ten right ventricular punctures with no consequences in 9 cases, c) two cases of shock, one of which was due to a pre-existing septicaemia of pulmonary origin, d) two non-sustained ventricular arrhythmias. The minor incidents were six vasovagal syndromes during the procedure and four paroxysmal supraventricular arrhythmias. Emergency surgical drainage was required (n = 3) for a failed procedure and late surgical drainage (n = 12) for persistence or recurrence of the effusion. No surgical drainage was required in the 17 patients placed under continuous aspiration. Echo-guided pericardiocentesis is a simple procedure and provides rapid haemodynamic relief in subjects generally in serious condition. Continuous aspiration may help avoid the need for surgical drainage for persistence or recurrence of the effusion.


Assuntos
Tamponamento Cardíaco/etiologia , Ecocardiografia , Derrame Pericárdico/complicações , Idoso , Tamponamento Cardíaco/diagnóstico por imagem , Tamponamento Cardíaco/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Derrame Pericárdico/diagnóstico por imagem , Derrame Pericárdico/cirurgia , Pericárdio/diagnóstico por imagem , Pericárdio/cirurgia , Punções , Sucção
13.
Arch Mal Coeur Vaiss ; 91(12 Suppl): 35-42, 1998 Dec.
Artigo em Francês | MEDLINE | ID: mdl-9891820

RESUMO

Echocardiography allows distinction between the diastolic dysfunction of hypertrophic or restrictive cardiomyopathies and the systolic dysfunction of dilated cardiomyopathy. The diagnosis and prognosis may be deduced from echocardiographic parameters. In hypertrophic cardiomyopathy systolic function is normal and there is asymmetric left ventricular hypertrophy (> 13 mm) associated with a reduced diastolic dimension and atrial dilatation resulting from diastolic dysfunction. The prognosis could be related to the severity of left ventricular hypertrophy; right ventricular hypertrophy is uncommon and its severity seems to be related to that of left ventricular hypertrophy. Restrictive cardiomyopathies are less common and amyloidosis is the commonest cause. Symmetric hypertrophy with reduced diastolic dimensions is observed; right ventricular involvement occurs in about 30% of cases. The prognosis seems to be related to the degree of parietal infiltration and, at advanced stages, systolic function is abnormal (fractional shortening < 20% with a left ventricular diastolic dimension > or = 55 mm) and rapidly fatal. Dilated cardiomyopathy is diagnosed when wall thickness is normal but left ventricular diastolic dimensions > 27 mm/m2 and ejection fraction < 45%. Right and left ventricular dimensions of the same size, left ventricular diastolic dimensions > 70 mm and left ventricular ejection fractions < 20% are poor prognostic indicators.


Assuntos
Cardiomiopatias/diagnóstico por imagem , Ecocardiografia Doppler , Adulto , Cardiomegalia/diagnóstico por imagem , Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Restritiva/diagnóstico por imagem , Humanos , Prognóstico
15.
Chest ; 112(3): 842-3, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9315824

RESUMO

Primary pulmonary hypertension (PPH) is often associated with angina-like chest pain, the mechanism of which is controversial. A 37-year-old woman with severe PPH and angina had transient ischemic ECG changes and reversible anterior perfusion defect on 201thallium scintigraphy. Coronary angiography revealed severe stenosis of the left main coronary artery (LMCA) and otherwise normal vessels. After heart-lung transplantation, examination of the explanted heart showed normal coronary arteries. Compression of the LMCA by the dilated pulmonary artery trunk was responsible for myocardial ischemia. This mechanism should be considered in patients with PPH and angina and might contribute to the high sudden death rate.


Assuntos
Doença das Coronárias/etiologia , Hipertensão Pulmonar/complicações , Adulto , Angina Pectoris/etiologia , Constrição Patológica/diagnóstico por imagem , Constrição Patológica/etiologia , Constrição Patológica/cirurgia , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/cirurgia , Morte Súbita Cardíaca/etiologia , Dilatação Patológica/patologia , Eletrocardiografia , Feminino , Transplante de Coração-Pulmão , Humanos , Hipertensão Pulmonar/patologia , Hipertensão Pulmonar/cirurgia , Isquemia Miocárdica/etiologia , Artéria Pulmonar/patologia , Cintilografia , Compostos Radiofarmacêuticos , Radioisótopos de Tálio
16.
Arch Mal Coeur Vaiss ; 90(7): 967-73, 1997 Jul.
Artigo em Francês | MEDLINE | ID: mdl-9339258

RESUMO

The efficacy of a system of active diastolic synchronised coronary perfusion was studied during prolonged balloon angioplasty in 8 sheep. In the first part of the study (group 1) including 5 animals, the aim was to study the effects of high and constant flow (48 ml/min) for 90 minutes perfusion on haemolysis, the arterial wall and the perfused myocardium. The second part of the study (group 2), including 3 animals, assessed whether flow adapted to the extent of the vascular bed perfused (24 to 40 ml/min) could protect the myocardium for an interval of 60 minutes. In group 1, after 90 minutes of perfusion (48 ml/min), there was no haemolysis, or jet lesion of the arterial wall distal to the catheter tip. On the other hand, the creatinine phosphokinase levels increased at the 60th minute (188 vs 119 i.u./l for controls) and at the 90th minute (238 vs 119 i.u./l; p < 0.05). Moreover, the perfused myocardium was the site of histological lesions. These observations showed myocardial changes due to the "overflow phenomenon". In group 2, the flow rate was adapted to each animal, increasing progressively until disappearance of electrocardiographic signs of ischaemia (ST elevation) and maintained for 60 minutes. No signs of haemolysis, jet lesions or myocardial changes were observed, with absence of creatinine phosphokinase elevation and histological abnormalities. These preliminary results show that the system investigated allowed myocardial protection after arterial occlusion for an interval of 60 minutes.


Assuntos
Isquemia Miocárdica/prevenção & controle , Reperfusão Miocárdica/métodos , Angioplastia Coronária com Balão , Animais , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea , Transfusão de Sangue Autóloga , Circulação Coronária , Vasos Coronários , Creatina Quinase/sangue , Modelos Animais de Doenças , Isquemia Miocárdica/fisiopatologia , Reperfusão Miocárdica/instrumentação , Ovinos , Fatores de Tempo
17.
Am J Cardiol ; 79(5): 635-8, 1997 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-9068523

RESUMO

Angiotensin-converting enzyme inhibitors have been shown to increase maximal muscle blood flow in parallel to peak VO2 in patients with congestive heart failure (CHF). Whether this increase shifts factors limiting peak aerobic capacity from periphery (skeletal muscle or vessels) to central factors (cardiac or respiratory) is unknown. Comparison of peak oxygen consumption (VO2) obtained during leg cycling (VO2 leg) with peak VO2 obtained during combined leg cycling and arm cranking (VO2 arm + leg) allows determination of the relative role of central or peripheral factors. We compared VO2 leg with VO2 arm + leg before and after 3 months of therapy with quinapril 40 mg in 16 patients with CHF (age 53 +/- 13 years) due to left ventricular systolic dysfunction (ejection fraction 0.25 +/- 0.07). Before quinapril, VO2 arm + leg was significantly higher than VO2 leg (19.0 +/- 3.3 vs 16.9 +/- 3.8 ml/kg/min, p < 0.001), whereas after therapy these 2 values were similar (20.3 +/- 4.3 vs 21.0 +/- 4.3 ml/kg/min; p = NS), indicating that patients were no longer limited by peripheral factors. Besides, VO2 leg increase after therapy was higher in patients in whom difference between VO2 arm + leg and VO2 leg was the greatest (i.e., in patients who were initially more limited by peripheral factors). Simultaneously, calf peak reactive hyperemia and circumference significantly increased, indicating an improvement in vascular dilating capacity and an increase in skeletal muscle mass. No significant modification occurred in the forearm. Thus, patients who improved the most after 3 months of quinapril therapy were those who were initially limited by peripheral factors. The restricting role of these factors was reduced after quinapril therapy.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Isoquinolinas/uso terapêutico , Consumo de Oxigênio , Esforço Físico/fisiologia , Tetra-Hidroisoquinolinas , Braço/fisiologia , Circulação Coronária/efeitos dos fármacos , Teste de Esforço , Feminino , Seguimentos , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Hiperemia/fisiopatologia , Perna (Membro)/irrigação sanguínea , Perna (Membro)/fisiologia , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Consumo de Oxigênio/efeitos dos fármacos , Quinapril , Fluxo Sanguíneo Regional/efeitos dos fármacos , Respiração/efeitos dos fármacos , Volume Sistólico , Vasodilatação , Disfunção Ventricular Esquerda/complicações
20.
Arch Mal Coeur Vaiss ; 89 Spec No 2: 39-45, 1996 Jul.
Artigo em Francês | MEDLINE | ID: mdl-8881505

RESUMO

There are three types of cardiomyopathy: hypertrophic, dilated and restrictive. The diagnosis and prognosis of these three types may be assessed from Doppler echocardiographic data. In hypertrophic cardiomyopathy, the diagnostic criterion is parietal hypertrophy. This hypertrophy is asymmetrical and usually affects the interventricular septum. Ventricular outflow obstruction is not necessarily present. The left ventricle is small and analysis of mitral inflow usually shows abnormal relaxation (E/A ratio < 1). The prognosis of this type of cardiomyopathy seems to be related to ventricular arrhythmias and the relationship between the hypertrophy and the presence of arrhythmias remains controversial. Dilated cardiomyopathy is characterized by ventricular walls of normal or decreased thickness, an increase in left ventricular dimensions and a reduction in the ejection fraction. An end-diastolic left ventricular dimension > 70 mm and an ejection fraction < 25% are poor prognostic factors. Left ventricular filling is abnormal and severe cases show a restrictive type of profile; in this case, an E/A ratio > 2 carries a poor prognostic. A mitral deceleration time of E wave < 150 msec usually indicates a bad outcome. Restrictive types of cardiomyopathy are more rare, amyloidosis being the commonest cause. Symmetrical wall thickening and a small ventricular chamber are observed. In advanced stages with abnormal systolic function, an E/A mitral ratio > 2 and deceleration time < 150 msec, the outcome is rapidly fatal.


Assuntos
Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Cardiomiopatia Restritiva/diagnóstico por imagem , Ecocardiografia Doppler , Adulto , Amiloidose/complicações , Cardiomiopatia Dilatada/complicações , Cardiomiopatia Hipertrófica/complicações , Cardiomiopatia Restritiva/complicações , Cardiomiopatia Restritiva/etiologia , Morte Súbita Cardíaca/etiologia , Diástole , Humanos , Pessoa de Meia-Idade , Prognóstico , Sensibilidade e Especificidade , Sístole , Disfunção Ventricular Esquerda/diagnóstico por imagem
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