RESUMO
Haemorheological characteristics were measured in a group of 52 patients with essential arterial hypertension (HT), and were compared with those of a group of normotensive subjects. The relationships between the arterial blood pressure (BP), the echocardiographic indices of left ventricular hypertrophy (LVH), and the haemorheological measurements, were studied. The group of hypertensive patients was found to have a hyperviscosity syndrome with significant elevations of blood viscosity at all shear rates (for gamma = 0.20/s, 29.6 +/- 0.6 versus 28.0 +/- 0.3 mPa.s, P less than 0.01: for gamma = 128/s, 4.2 +/- 0.05 versus 4.1 +/- 0.02 mPa.s, P less than 0.02, of plasma viscosity (1.29 +/- 0.01 versus 1.22 +/- 0.06 cSt, P less than 0.001); of erythrocyte aggregation index (17.8 +/- 0.06 versus 14.6 +/- 0.4, P less than 0.001); of erythrocyte filterability index (13.3 +/- 0.5 versus 8.8 +/- 0.2, P less than 0.001) and plasma fibrinogen level (3.4 +/- 0.9 versus 2.8 +/- 0.6 g/l, P less than 0.02). The haematocrit did not differ from that of normotensive subjects (43.3 +/- 0.6 versus 44.7 +/- 0.5%, NS). The left ventricular mass was increased and was positively correlated with the blood viscosity at a high shear rate (r = 0.38, P less than 0.01) and with the erythrocyte aggregation index (r = 0.47, P less than 0.01). Systolic, diastolic, and mean arterial blood pressures were positively correlated with the left ventricular mass (r = 0.34-0.47, P less than 0.05) and with the erythrocyte aggregation index (r = 0.42-0.46, P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Viscosidade Sanguínea , Cardiomegalia/etiologia , Agregação Eritrocítica , Deformação Eritrocítica , Hipertensão/sangue , Adulto , Idoso , Ecocardiografia , Feminino , Fibrinogênio/análise , Hematócrito , Humanos , Hipertensão/complicações , Masculino , Pessoa de Meia-IdadeRESUMO
The hemodynamic and electrophysiologic effects of rilmenidine were examined after single oral administration to hypertensive patients. In 8 untreated hypertensive patients, cardiac output, pulmonary pressure and blood pressure were measured before and for 10 hours after the administration of 25 micrograms/kg of rilmenidine (1.3 to 2.4 mg, mean 1.88). In addition, electrophysiologic investigations were performed before and 2 hours after administration. Hemodynamics were repeated in 8 other hypertensive patients receiving 50 micrograms/kg rilmenidine (3.0 to 4.8 mg, mean 3.85 mg). The electrophysiologic study was repeated in 8 other hypertensive patients receiving 50 micrograms/kg of rilmenidine (3.2 to 4.4 mg, mean 3.90). In contrast to the results obtained at the dose of 50 micrograms/kg, there was no significant variation in pulmonary arterial pressure, cardiac index or stroke index after administration of 25 micrograms/kg. No significant variation was observed in heart rate, sinus function, conduction parameters or atrial, nodal and ventricular refractory periods after administration of 25 and 50 micrograms/kg. Rilmenidine, after single oral administration at the 25 micrograms/kg dose, led to a significant reduction in blood pressure and peripheral resistance without any significant change in cardiac output; the 25- and 50-micrograms/kg doses led to no alteration in heart rate and cardiac electrophysiology.
Assuntos
Agonistas Adrenérgicos beta/farmacologia , Sistema de Condução Cardíaco/fisiopatologia , Hemodinâmica/efeitos dos fármacos , Hipertensão/fisiopatologia , Oxazóis/farmacologia , Agonistas Adrenérgicos beta/uso terapêutico , Adulto , Pressão Sanguínea/efeitos dos fármacos , Débito Cardíaco/efeitos dos fármacos , Estimulação Cardíaca Artificial , Eletrocardiografia , Eletrofisiologia , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Oxazóis/uso terapêutico , Rilmenidina , Volume Sistólico/efeitos dos fármacos , Fatores de TempoRESUMO
Seventeen patients with stable congestive heart failure (class II and III New York Heart Association) received intravenous and oral enoximone in a 2-part study. Hemodynamic data were first obtained after intravenous administration of 0.75 mg/kg of enoximone; data were again obtained after 12 weeks of therapy with either oral enoximone (150 mg 3 times daily) or placebo. The efficacy and safety of oral enoximone were also studied in a 12-week, double-blind randomized format. In the intravenous study, enoximone was delivered over 5 minutes and hemodynamic data were measured for up to 12 hours after. Cardiac index increased 2.76 +/- 0.63 to 3.42 +/- 0.72 liters/min/m2), pulmonary wedge pressure decreased (19.5 +/- 8.8 to 14.6 +/- 8.0 mm Hg) as did mean arterial blood pressure (101 +/- 14.8 to 85 +/- 13.7 mm Hg) and systemic vascular resistance (1,880 +/- 573 to 1,254 +/- 383 dynes s cm-5). Heart rate increased slightly (82 +/- 17 to 86 +/- 14 beats/min). All these changes were maximal 1 to 2 hours after infusion and lasted 8 hours at least. Patients were then randomized double-blind to oral treatment. Baseline values showed that the 7 patients who received placebo had more severe CHF. Therefore, comparison might be biased. Patient overall assessment showed a continuous benefit in both groups. Ejection fraction improved from 30.1 +/- 6.8% to 33.9 +/- 9.9% in the enoximone group while it remained unchanged with placebo (23.4 +/- 6.5% to 23.4 +/- 1.5%).(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Cardiotônicos/administração & dosagem , Insuficiência Cardíaca/fisiopatologia , Hemodinâmica/efeitos dos fármacos , Imidazóis/administração & dosagem , Administração Oral , Adulto , Cardiotônicos/uso terapêutico , Ensaios Clínicos como Assunto , Método Duplo-Cego , Enoximona , Feminino , Seguimentos , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Imidazóis/uso terapêutico , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Distribuição AleatóriaRESUMO
Diltiazem is a calcium antagonist with demonstrated experimental cardioprotective effects. Its effects on myocardial infarct size were studied in 34 patients admitted within 6 hours after the first symptoms of acute myocardial infarction. These patients were randomized, double-blind to placebo or diltiazem (10-mg intravenous bolus followed by 15 mg/hr intravenous infusion during 72 hours, followed by 4 X 60 mg during 21 days). Myocardial infarct size was assessed by plasma creatine kinase and creatine kinase-MB indexes, perfusion defect scores using single-photon emission computed tomography with thallium-201 and left ventricular ejection fraction measured by radionuclide angiography. Tomographic and angiographic scanning was performed serially before randomization, after 48 hours and 21 days later. Groups were comparable in terms of age, sex, inclusion time and baseline infarct location and size. Results showed no difference in creatine kinase and creatine kinase-MB data between controls and treated patients, a significant decrease in the perfusion defect scores in the diltiazem group (+0.1 +/- 3.0 placebo vs -2.2 +/- 1.9 diltiazem, p less than 0.02) and a better ejection fraction recovery in the diltiazem group (-4.2 +/- 7.4 placebo vs +7.7 +/- 11.2 diltiazem, p less than 0.05). Myocardial infarct size estimates from perfusion defect scores and enzyme data were closely correlated. These preliminary results suggest that diltiazem may reduce ischemic injury in acute myocardial infarction.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Ensaios Enzimáticos Clínicos , Diltiazem/uso terapêutico , Infarto do Miocárdio/tratamento farmacológico , Angiografia Cintilográfica , Radioisótopos de Tálio , Tomografia Computadorizada de Emissão , Ensaios Clínicos como Assunto , Creatina Quinase/sangue , Diltiazem/efeitos adversos , Diltiazem/sangue , Método Duplo-Cego , Eletrocardiografia , Humanos , Isoenzimas , Monitorização Fisiológica , Infarto do Miocárdio/sangue , Infarto do Miocárdio/diagnóstico , Distribuição Aleatória , TecnécioRESUMO
Adequate processing of left ventricular angiograms depends on the visualisation of all segments of the ventricular wall. At the same time, subtraction of different images can enhance different heart segments but commercially available methods do not allow simultaneous viewing of several images masked by different processes. Using our software, for each studied frame, a four quadrant display permits the simultaneous visualisation of a mask mode image, a diastolic-systolic difference image, an image obtained by subtraction of a frame at the same cycle time and a composite mask subtracted image. The composite mask image is obtained by weighting three images according to videodensitometric measurements by reference to previously acquired data. This method facilitates contour delineation and computation of the ejection fraction by area-length method. Correlation with radionuclide estimates of left ventricular ejection fraction is higher (n = 60, r = 0.90, SEE = 8%) than using the classical mask mode display (n = 60, r = 0.82, SEE = 11%). In a subgroup of 30 patients the contrast medium was injected in an antecubital vein and the correlation coefficient remained satisfactory (n = 30, r = 0.89, SEE = 7%) when compared with the classical subtraction technique (n = 30, r = 0.70, SEE = 12%). We therefore conclude that the composite mask method gives comparatively similar values for left ventricular ejection fraction to those acquired by radionuclide angiography.
Assuntos
Angiografia Digital/métodos , Doença das Coronárias/diagnóstico , Imagem do Acúmulo Cardíaco de Comporta , Volume Sistólico , Feminino , Humanos , Iohexol , Masculino , Pessoa de Meia-Idade , SoftwareRESUMO
To determine long-term survival and the prognostic factors of dilated cardiomyopathy, we retrospectively studied a consecutive series of 111 patients (95 men, 16 women, mean age: 45.5 +/- 8.1 years) undergoing cardiac catheterization and diagnostic coronary angiography from January 1970 to December 1979. The inclusion criteria were: normal coronary angiography, diffuse hypokinesia of the left ventricle and left ventricular ejection fraction less than 50%. Base-line clinical data were collected from the hospital records and follow-up data were obtained from the general practitioners and cardiologists. A questionnaire was sent to all living patients. The length of follow-up ranged from 6 to 16 years. Six patients (5%) were lost to follow-up. At the time of catheterization, a majority of the patients had dyspnea and were in New York Heart Association (NYHA) classes II (41%) and III (31%). Clinical history revealed an excessive alcohol consumption in 56% of the patients. During follow-up, 66 patients (63%) died (heart failure: 37%; sudden death: 19%; non-cardiac death: 15%; unknown cause: 27%). Actuarial survival was 90, 50, and 33% at 1, 5, and 10 years, respectively. Univariate analysis revealed that 10-year mortality was related to: left ventricular ejection fraction less than 30%; left ventricular end-diastolic pressure greater than 10 mm Hg; cardiothoracic ratio greater than 54%; episodes of heart failure; left ventricular end-diastolic volume greater than 200 ml/m2, dyspnea of NYHA class III or IV; absence of smoking; absence of moderate systemic hypertension; electrocardiographic evidence of left ventricular hypertrophy and mean systemic arterial pressure greater than 95 mm Hg.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Cardiomiopatia Dilatada/diagnóstico , Adulto , Pressão Sanguínea , Cateterismo Cardíaco , Cardiomiopatia Dilatada/mortalidade , Cardiomiopatia Dilatada/fisiopatologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Volume SistólicoRESUMO
Ventriculo-atrial conduction was studied by ventricular pacing in three groups of patients: 34 cases with the preexcitation syndrome on surface ECG, 35 cases with documented paroxysmal atrial tachycardia but with otherwise normal ECGs and 120 cases without either of these two conditions. This conduction time was unchanged up to pacing rates of over 160/min in 88 p. 100 cases with preexcitation and was thus a sign of a nodal short-circuit. This phenomenon was also observed in 85 p. 100 cases with isolated paroxysmal atrial tachycardia and in 20 p. 100 normal cases which suggests the presence of a latent accessory pathway in these patients.
Assuntos
Arritmias Cardíacas/diagnóstico , Sistema de Condução Cardíaco/fisiologia , Adolescente , Adulto , Idoso , Criança , Eletrocardiografia , Átrios do Coração , Sistema de Condução Cardíaco/fisiopatologia , Ventrículos do Coração , Humanos , Pessoa de Meia-Idade , Síndrome , Taquicardia Paroxística/diagnóstico , Síndrome de Wolff-Parkinson-White/diagnósticoRESUMO
Measurement of the circulation time using dycholium allows us to estimate the arrival time of the opaque medium at the renal pedicle. Xrays taken at a very early stage will show up the abdominal aorta and renal arteries. The pictures can then be greatly clarified by a subtraction technique. In this way we have a method which, with but little change in the traditional technique for intravenous pyelography, enters into the question of whether renal arteriography is justified when it is required to demonstrate only the major arterial vessels.
Assuntos
Angiografia/métodos , Artéria Renal/diagnóstico por imagem , Urografia/métodos , Humanos , Técnica de SubtraçãoRESUMO
The electrophysiological properties of carocainide a new Class I antiarrhythmic agent (Delalande Research Centre) were studied after intravenous injection of 3.5 mg/kg in 5 minutes in 16 patients aged 24 to 66 years. Five minutes after the injection there was a significant increase (p less than 0.01) in the HV (+/- 12.8 +/- 10.5 msec), AH (+ 21.8 +/- 14 msec) and PR intervals (+ 43.8 +/- 24.2 msec) and in the duration of QRS (+ 20.6 +/- 9.9 msec). The anterograde and retrograde Wenckebach points were decreased (-42 +/- 43 bpm and - 52 +/- 36 bpm respectively, p less than 0.05). All these effects reverted progressively 20 minutes after injection and disappeared by the 40th minute, which corresponds to the pharmaco-kinetic profile of the patient. There were no changes in blood pressure, sinus node function or refractory periods except for the retrograde refractory periods which were prolonged (+ 87 +/- 41 msec). Atrial fibrillation was induced in 2 patients and atrial flutter in 2 others by the extrastimulus technique. These arrhythmias could not be reproduced in these 4 patients during the 40 minutes after injection of carocainide. Five other patients with reciprocating nodal tachycardia induced by atrial extrastimuli had their arrhythmia interrupted by the carocainide injection. We conclude that carocainide acts mainly on atrio-ventricular and intra-ventricular conduction. The results obtained in patients with tachycardias suggest that the product is effective in atrial arrhythmias and paroxysmal junctional tachycardia.
Assuntos
Antiarrítmicos/farmacologia , Sistema de Condução Cardíaco/efeitos dos fármacos , Pirrolidinas/farmacologia , Adulto , Antiarrítmicos/administração & dosagem , Antiarrítmicos/metabolismo , Antiarrítmicos/uso terapêutico , Nó Atrioventricular/efeitos dos fármacos , Eletrocardiografia/métodos , Feminino , Humanos , Injeções Intravenosas , Cinética , Masculino , Pessoa de Meia-Idade , Pirrolidinas/administração & dosagem , Pirrolidinas/metabolismo , Pirrolidinas/uso terapêutico , Síncope/fisiopatologia , Taquicardia Paroxística/tratamento farmacológico , Taquicardia Paroxística/fisiopatologiaRESUMO
To evaluate the dose-effect relationship of antihypertensive drugs is essential to a rational determination of their effective dosage. Two double-blind and strictly controlled trials have demonstrated the effectiveness of perindopril 4 mg orally in the treatment of mild to moderate arterial hypertension (100 less than DAP less than 120 mmHg). The drug remained effective 24 hours after the last dose. The 2 mg dose proved insufficient to obtain a significant reduction of blood pressure. In case where the 4 mg dose was not sufficiently active, a better antihypertensive effect could be achieved with an 8 mg dose without major untoward reactions. The antihypertensive activity of perindopril was parallel to the percentage of angiotensin-converting enzyme inhibition induced by the compound. This study also illustrates clearly the value of semi-automatic blood pressure recording with the Dinamap system in the determination of dose-effect relationship, compared with the conventional sphygmomanometric method.
Assuntos
Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Hipertensão/tratamento farmacológico , Indóis/administração & dosagem , Administração Oral , Adulto , Idoso , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Ensaios Clínicos como Assunto , Relação Dose-Resposta a Droga , Método Duplo-Cego , Avaliação de Medicamentos , Humanos , Indóis/uso terapêutico , Pessoa de Meia-Idade , PerindoprilRESUMO
Forty patients with normal resting ECGs and a history of paroxysmal junctional tachycardia underwent endocavitory electrocardiography. Accessory atrioventricular pathways were demonstrated in 34 patients (82.5%), 14 of whom (35%) had Kent bundles. The ventriculo-atrial conduction time during ventricular stimulation was constantin 85% of the 40 patients but increased after injection of striadyne (ATP). This may suggest a reentry circuit partially bypassing the atrioventricular node.
Assuntos
Nó Atrioventricular/fisiopatologia , Sistema de Condução Cardíaco/fisiopatologia , Condução Nervosa , Taquicardia Paroxística/fisiopatologia , Trifosfato de Adenosina/farmacologia , Adulto , Idoso , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Condução Nervosa/efeitos dos fármacos , Fatores de TempoRESUMO
The clinical profile of coronary patients admitted to cardiac rehabilitation centres after myocardial infarction has changed considerably in the last 15 years. Complementary investigations (coronary angiography, studies of left ventricular function) provide accurate information which improves the process of rehabilitation. Global management of the coronary patient requires and justifies, especially in young adults, taking into consideration the physical, psychological and socio-professional consequences of a myocardial infarction. The indications of rehabilitation are much more comprehensive nowadays. Even patients with significant haemodynamic impairment can benefit from a stay in a specialised centre. Contraindications are usually only temporary. Finally, an enquiry performed in 33 French cardiac rehabilitation centres shows large variations in methods, personnel and organisation. However, as a general rule, a 3 week stay seems to be adequate but it is logical to continue rehabilitation when the patients goes home to pursue and maintain at long term the results obtained on discharge from a specialised centre.
Assuntos
Infarto do Miocárdio/reabilitação , Centros de Reabilitação , França , Humanos , Tempo de Internação , Modalidades de FisioterapiaRESUMO
M mode echocardiography may be difficult or even impossible from the standard transducer positions (parasternal or subcostal) in obese, broncho-emphysematous patients and subjects with thoracic malformations. For this reason, the authors used the oesophageal route. A 2.25 MHz unfocused 11 mm diameter transducer was attached to a wire enabling it to be orientated. The patients were asked to swallow this probe after local anaesthesia. The aortic ring served as a landmark for other cardiac structures. The technique was well tolerated and no complications ensued. Fifty seven patients were examined: echocardiography from the standard positions was of mediocre quality in 55%. Excellent recordings were obtained by the oesophageal route, of the aortic ring (Ao, 100% of cases), of the aortic cusp opening (ACO, 92% of cases) and of the anterior mitral leaflet (AML, 96.5% of cases); the recording of the left ventricle was more difficult (LV, 45.5% of cases). Exceptionally good recording were obtained of the right heart. Correlations between the measurements made from the oesophageal and standard positions were excellent with respect to the aortic structures (Ao: r = 0.92; ACO: r = 0.92) and LV dimensions (systolic: r = 0.82; diastolic: r = 0.87). The correlations between the measurements of DE mitral valve amplitude, EF slope and left atrial dimension were mediocre (r = 0.63, r = 0.72 and r = 0.69, respectively). In 6 cases, this recording technique enabled a precise diagnosis to be made. Oesophageal echocardiography is simple and well tolerated and should effectively complete the arsenal of cardiological ultrasonic techniques.
Assuntos
Ecocardiografia/métodos , Coração/anatomia & histologia , Esôfago , Cardiopatias/diagnóstico , HumanosRESUMO
The authors report a series of 13 patients, 8 men and 5 women, with an average age of 68 years (range 39 to 87 years) presenting with documented inferior infarction with anteroseptal extension in 2 cases. These patients developed LBBB (complete in 9 cases, incomplete in 4 cases). This complications occurred in the acute phase in 8 cases and 4 months to 9 years later (average 4,5 years) in the other 5 cases. The block was intermittent in 4 patients and became permanent in all cases. The diagnosis of inferior infarction with LBBB was made by vectorcardiography (VCG) in 5 out of the 13 patients (38,4 p. 100) on the criteria suggested by Starr. 3 of the 8 false negative results were directly related to the block which masked the ECG and VCG signs of inferior infarction. The VCG signs observed were an upwards displacement of the QRS loop with preservation of the superior orientation of the initial forces (5 cases). Atypical appearances of LBBB were observed in 2 cases with a posterior and right-sided shift of the efferent loop following the anterior and left-sided orientations of the initial forces. The sensitivity of the VCG and ECG is mediocre in inferior infarction with LBBB because the block may mask the electrical signs of inferior infarction. The specificity of the VCG could not be assessed because of the mode of selection of the patients and the small number of cases.
Assuntos
Bloqueio de Ramo/complicações , Infarto do Miocárdio/diagnóstico , Vetorcardiografia , Adulto , Idoso , Bloqueio de Ramo/diagnóstico , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicaçõesRESUMO
Blood viscosity (BV) is one determinant of total arterial resistance (TAR) which is usually increased in hypertension. This increase is mainly related to vasoconstriction. In this study, we investigated the blood rheological properties in hypertension and their relation to blood pressure (BP) and left ventricular hypertrophy (LVH) since the latter could be related to increased TAR. BP and echocardiographic measurement of left ventricular mass (LVM) according to Devereux were measured and blood samples obtained from 22 untreated hypertensives aged 31 to 62 (13 men, 9 women) Control group consisted of 30 age-matched, normotensive blood donors. Results are shown in table I. (Formula: see text). A positive significant correlation was found between LVM and BV (r = 0.50; p less than 0.05) red cell filterability (r = 0.53; p less than 0.05) and red cell aggregability (r = 0.57; p less than 0.02). These results suggest that erythrocyte abnormalities are one of the determinants of the hyperviscosity syndrome in hypertension. Some variables of this syndrome were related to LVM and could therefore be among the determinants or a consequence of LVH in hypertensives.
Assuntos
Viscosidade Sanguínea , Hipertensão/sangue , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Haemorrheological disturbances have already been described in ischaemic heart disease. However, it has not been established whether these changes are secondary to the ischaemia and/or myocardial infarction or whether they play a role in initiating or sustaining the haemodynamic abnormalities which cause infarction. We report our results observed in 14 patients aged 48 to 75 years admitted to the coronary care unit with a diagnosis of acute coronary insufficiency defined as typical persistent anginal pain resistant to glyceryl trinitrate associated with specific ECG changes (without pathological Q waves or increased serum CPK concentrations). Blood samples were obtained on admission for determination of: haematocrit, total blood viscosities at different levels of shear with the patients hematocrit and with corrected hematocrits, total blood filtrability, plasma viscosity and plasma albumin fraction. All patients received 800 mg lidocaine, 40 mg chlorezepate, adequate anticoagulant doses of heparin and a specific antianginal drug: amiodarone, nifedipine or diltiazem. Six patients had a favourable outcome and were discharged from the Coronary Care Unit without myocardial infarction (Group I); the remaining 8 patients (Group II) developed documented changes of myocardial infarction between the 12th and 4th day after admission (see the Table in the text). The haemorrheological parameters on admission of the two patients groups were compared. The abnormalities observed were significantly more severe in the group developing myocardial infarction. This suggests that these changes may play a major role in initiating conditions leading to myocardial necrosis. These observations confirm the results of other workers who have also shown a relationship between the severity of infarction and the incidence of haemodynamic complications and changes in blood viscosity and filtrability.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Viscosidade Sanguínea , Hematócrito , Infarto do Miocárdio/sangue , Albumina Sérica/análise , Idoso , Quimioterapia Combinada , Agregação Eritrocítica , Deformação Eritrocítica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/prevenção & controle , Reologia , SíndromeRESUMO
The authors have studied the haemodynamic role of atrial systole in patients in the acute stage of a myocardial infarction, usually with left ventricular failure. Their main comparison is between the results obtained with stimulation of the right ventricle at a fixed rate and those obtained with bifocal stimulation, thus restoring the atrio-ventricular sequence. The authors discuss their results, and especially their findings of improvement in cardiac output and systemic arterial blood pressure. They raise the question of synchronous stimulation in cases of infarction with heartblock complicated by left ventricular failure, and also of re-establishing sinus rhythm in cases of arrhythmia of supraventricular origin.
Assuntos
Átrios do Coração/fisiopatologia , Hemodinâmica , Contração Miocárdica , Infarto do Miocárdio/fisiopatologia , Doença Aguda , Adulto , Idoso , Arritmias Cardíacas/fisiopatologia , Débito Cardíaco , Estimulação Elétrica , Feminino , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Report of 107 cases of primary transportation in ambulances especially equipped for coronary patients monitoring. The various delays of admission were studied and the complications occuring during transportation were analyzed, together with the various therapeutic methods applied. On the basis of this personal experience, and to attempt at diminishing the mortality at the acute stage of myocardial infarction, it was advised: --a careful information of the public, --a systematic training of the physicians, --a logic organization of emergency care. Only a coherent set up of fixed and mobile units might result in improvement of the prognosis of the first hours after myocardial infarction.
Assuntos
Ambulâncias , Cardiopatias/terapia , Ressuscitação , Transporte de Pacientes , França , Infarto do Miocárdio/terapiaRESUMO
A case of reentrant tachycardia with narrow and wide ventricular complexes without appearances of preexcitation is reported. Electrophysiological investigation showed complete retrograde atrioventricular block during tachycardia; left bundle branch block did not show the tachycardia rate. The reentry loop probably comprised: the His bundle, the right bundle branch, a right Mahaïm bundle and possibly a myocardial bridge. Possible intra-hisian reentry is discussed. The initiation of the tachycardia is analysed together with the possible consequences of permanent cardiac pacing.
Assuntos
Bloqueio Cardíaco/complicações , Taquicardia/fisiopatologia , Fascículo Atrioventricular/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Marca-Passo Artificial , Taquicardia/terapiaRESUMO
Bidirectional ventricular tachycardia, defined as the rapid alternation of the QRS complexes with successive opposing axial deviation, is a rare arrhythmia. In the rare cases which have undergone endocavitary investigations, an infrahisian origin has generally been proved. However, the mechanism of these tachycardias remains poorly understood and is discussed with respect to a new case. Bidirectional tachycardia occurred in a 79 year old woman with previous diaphragmatic and anterior wall infarction. It was a wide QRS tachycardia at 180/min with a succession of ventriculogrammes of opposing axis in the frontal plane and permanent right bundle branch block over the right precordium. The two types of tachycardia were observed, monomorphic type A or Type B or a combination of the two realising an A-B bidirectional tachycardia. The origin of these episodes, which occurred on a background of atrial tachycardia at about 100/min, was ventricular as shown by the absence of a His potential before the ventricular complexes in tachycardia. The presence of ventricular extrasystoles with relatively fixed coupling intervals, and the results of endocavitary investigation were suggestive of a reentry phenomenon ventricular extrastimuli were capable of transforming the bidirectional into monomorphic tachycardia and vice versa; this suggests that A was at times the origin of a reentry B, but protected by A, tachycardia B could be sustained. In the light of previously reported cases with documented endocavitary investigation and this new case, it seems possible to talk in terms of true "bidirectional ventricular tachycardia", a tachycardia whose mechanism is obscure but certainly not univocal.