RESUMO
Coronary arteriography and biplane ventriculography were performed in 51 patients during the acute (mean of 6.6 hours after onset of symptoms) and chronic (1 to 3 months after admission) phase of myocardial infarction. Twenty-four patients were treated in a conventional manner. In 27 patients, reperfusion was achieved with intracoronary streptokinase after 24 +/- 20 minutes of infusion. Peak creatine kinase and cumulative creatine kinase release were derived from serial creatine kinase measurements. Ejection fraction and the length of the akinetic or dyskinetic segments were calculated in the chronic phase. The time interval between onset of symptoms and peak creatine kinase was significantly shorter for the streptokinase-treated patients as compared with the conventionally treated patients (13.5 +/- 5.3 versus 22.9 +/- 7.4 hours, p = 0.0001). Significant linear correlations were obtained for both streptokinase-treated and control patients, relating: 1) peak creatine kinase value to both length of the noncontracting segment and ejection fraction in the chronic phase, and 2) cumulative creatine kinase release to both length of the noncontracting segment and ejection fraction in the chronic phase. Patients treated with streptokinase experienced a relatively greater release of enzyme for a given infarct size as compared with those treated in a conventional manner. The difference in enzyme release between the two groups increased as infarct size increased. These observations may be explained by enhanced washout of enzyme from the infarct zone, secondary to reperfusion after intracoronary streptokinase therapy.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Creatina Quinase/metabolismo , Infarto do Miocárdio/enzimologia , Estreptoquinase/uso terapêutico , Circulação Coronária/efeitos dos fármacos , Feminino , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/patologia , Volume Sistólico/efeitos dos fármacosRESUMO
To assess the role of the fibrinolytic system in the pathogenesis of restenosis after percutaneous transluminal coronary angioplasty (PTCA), we determined the components of this system in a retrospective study, including 16 patients with restenosis (gr. A) and 19 patients with long-term success (gr. B). In both groups at baseline fibrinolytic activity (FA) is unchanged, whereas tissue plasminogen activator antigen (tPA-Ag) is significantly increased (gr. A: 147.0%; gr. B: 139.8%; p less than 0.01). Fibrinolytic capacity (FC) and tPA-Ag release are significantly reduced in the restenosis group (FC: 46.5%, p less than 0.05; tPA-Ag release: 48.3%, p less than 0.01) compared to normal controls as well as to gr. B (FC: 84.3%, p less than 0.05; tPA-Ag release: 79.0%, p less than 0.05). Relating to the contact activation system, F XII (79.5%, p less than 0.05) is significantly, and F XI (82.3%) is clearly reduced in gr. A. Protein C (PC) is significantly elevated in gr. B (117.5%, p less than 0.05). There is a negative correlation between plasminogen activator inhibitor (PAI 1) and HDL-cholesterol (r = 0.37, p less than 0.05). It appears, that there is a typical pattern of defective fibrinolysis in patients with restenosis after PTCA and that this might be a pathogenetic factor in the development of restenosis.
Assuntos
Angioplastia Coronária com Balão , Doença das Coronárias/sangue , Fibrinólise , Ativador de Plasminogênio Tecidual/sangue , Doença das Coronárias/terapia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos RetrospectivosRESUMO
Because there are several means by which a clinician may pharmacologically activate the fibrinolytic system for thrombolysis, the clinician must understand the clinical ramifications of the use of each pharmacologic agent. Intracoronary streptokinase is one such agent whose therapeutic use, although effective in many cases, must not be taken lightly. This article, therefore, reviews the pharmacology, therapeutic uses, and possible complications that could arise as a result of intracoronary streptokinase.
Assuntos
Infarto do Miocárdio/tratamento farmacológico , Estreptoquinase/uso terapêutico , Ensaios Clínicos como Assunto , Doença das Coronárias/tratamento farmacológico , Humanos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/fisiopatologia , Perfusão , Estreptoquinase/administração & dosagem , Estreptoquinase/efeitos adversosRESUMO
Background corrections applied on the left ventricular volume curve determined by the "gated blood pool"--method are based on an estimated rather than on a directly measured background. This imposes an uncertainty on the values determined from the volume curve, especially on the ejection fraction. A method which does not require background correction may be applied if all available measurement and evaluation facilities are utilized fully. High temporal and spatial resolution is of fundamental importance, permitting the exact determination of the time-dependent scintigraphic contour variations of the left ventricle during the mechanical action of the heart. A good criterion of the validity of the volume curves with respect to interfering background radiation is the ejection fraction calculated from these curves. The direct intercomparison of 10 ejection fractions obtained by an expanded "gated blood pool"-method, employing cardiac catheterization, immediately before a biplane laevocardiography demonstrated very good agreement. A small systematic underestimation of the ejection fraction by the nuclear method was observed. This understimulation shows that the influence of the true background is small if other interfering count rate contributions or methodical uncertainties are excluded systematically.
Assuntos
Débito Cardíaco , Volume Cardíaco , Ventrículos do Coração/diagnóstico por imagem , Angiografia , Cateterismo Cardíaco , Cardiografia de Impedância , Computadores/instrumentação , Eletrocardiografia/métodos , Humanos , CintilografiaRESUMO
In a 45 year old male patient with a history of previous inferior myocardial infarction and unstable angina pectoris, coronary angiography revealed two-vessel disease: a 60-70% lesion in the middle third of the LAD, and a 90% lesion in the middle third of the very large RCA. There was only a small akinetic segment in the posterobasal region of the left ventricle. During angiography total occlusion of the RCA occurred followed the clinical and electrocardiographic signs of impending inferior reinfarction. Recanalization of the occluded vessel was accomplished by using a guide-wire, which was passed through a Sones catheter, placed in the RCA. The patient's symptoms subsided and the electrocardiographic signs of acute ischemia reverted within eight minutes. Aortocoronary bypass surgery with revascularization of the LAD and RCA was performed within 3 hours after recanalization. Postoperatively there was no evidence of major tissue loss by enzyme or electrocardiographic criteria. Control angiography, performed on the ninth day postoperatively, revealed the graft to the RCA to be widely patent. Left ventricular function was unchanged. It is concluded, that the combined approach of early transluminal recanalization of the acutely occluded RCA followed by successful construction of a graft to this vessel, has averted necrosis of a major portion of the left ventricle. However, general use of this technique does not seem advisable at the present time.
Assuntos
Angiografia/efeitos adversos , Cateterismo Cardíaco , Angiografia Coronária , Doença das Coronárias/etiologia , Doença Aguda , Ponte de Artéria Coronária , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/cirurgia , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Coronary angiography was performed in the acute stage of myocardial infarction in 65 patients. The infarct-related vessel was occluded in 50 patients; it was narrowed greater than 90% in the remaining 15 patients. Control angiography was performed 55 +/- 46 d after acute myocardial infarction in 18 patients. In the chronic stage, five of thirteen previously occluded vessels showed antegrade filling of the distal segment. The narrowing at the site of previous obstruction was 80--95%. In two of five patients with a subtotal stenosis, the lumen of the infarct-related vessel was clearly larger in the chronic stage. The end-diastolic volume index increased significantly from 86 +/- 23 ml/m2 in the acute stage to 110 +/- 35 ml/m2 in the chronic stage (p less than 0.001). The increase in the end-systolic volume index from 42 +/- 15 ml/m2 to 63 +/- 31 ml/m2 was also statistically significant (p less than 0.005). Stroke volume index, ejection fraction, and the length of the akinetic segment (AKS) did not change significantly. There was a weak correlation between the end-systolic volume index and the length of the AKS in the acute stage (r = 0.489, p less than 0.05) and a better correlation in the chronic stage (r = 0.602, p less than 0.01). The ejection fraction and the length of the AKS correlated in the chronic stage only (r = 0.795, p less than 0.001).
Assuntos
Doença das Coronárias/etiologia , Ventrículos do Coração/fisiopatologia , Infarto do Miocárdio/complicações , Angiocardiografia , Humanos , Infarto do Miocárdio/diagnóstico por imagemRESUMO
The cardiotoxicity of commonly used contrast media such as sodium methylglucamine diatrizoate is related to nonphysiologic concentrations of ions and high osmolality. Following injection there is an excessive decrease in ambient calcium which disturbs the extracellular Na+/Ca2+ ratio and results in myocardial depression. In animal studies (anesthetized, intact mongrel dogs) this cardiodepressive effect could be fully compensated by adding 22.5 mEq/1 of ionic calcium to the contrast medium. In 16 patients studied for coronary artery disease (CAD) 72 injections of sodium methylglucamine diatrizoate, mainly in the left coronary artery, were thoroughly investigated. There was marked depression of left ventricular pressure (-22%) and (dP/dt)max (-27%), and marked heart rate slowing (-29%). Added calcium in the concentration cited reduced significantly (p < 0.001) the myocardial depression to -15% and -13%, respectively, but did not completely compensate it. The heart rate slowing was not altered significantly. It was concluded that the addition of calcium may be helpful when studying high-risk patients and using high injection volumes.
Assuntos
Meios de Contraste/efeitos adversos , Angiografia Coronária , Coração/efeitos dos fármacos , Angiografia , Animais , Cálcio/administração & dosagem , Cálcio/metabolismo , Cálcio/farmacologia , Diatrizoato de Meglumina/efeitos adversos , Cães , Frequência Cardíaca/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Humanos , Íons , Contração Miocárdica/efeitos dos fármacos , Miocárdio/metabolismo , Sódio/metabolismoRESUMO
To verify the predictive value of thallium exercise scintigraphy, 20 normal individuals and 60 patients with coronary artery disease (CAD) were examined, using a quantitative standard technique and receiver operating characteristic analysis. The sensitivity of thallium scintigraphy for the presence of CAD was 97% for patients with previous infarction and 85% for those without infarction. The sensitivity for the extent of CAD was 93% for vessels perfusing infarcted areas and only 67% for vessels without infarction. In patients without myocardial infarction, sensitivity for the number of diseased vessels decreased with increasing extent of CAD. An underestimation of hemodynamically significant stenoses was proven by a comparison with the results of exercise ventriculography. The predictive value of a normal scintigram at a high prevalence of CAD is as low as the predictive value of an abnormal scintigram at a low prevalence level (screening). Thallium scintigraphy is indicated in patients with a medium prevalence of CAD, e.g., in patients with atypical angina and in asymptomatic patients with pathologic ECG.
Assuntos
Doença das Coronárias/diagnóstico por imagem , Radioisótopos , Tálio , Adulto , Humanos , Pessoa de Meia-Idade , CintilografiaAssuntos
Angina Pectoris/tratamento farmacológico , Fibrinolíticos/administração & dosagem , Estreptoquinase/administração & dosagem , Angina Pectoris/etiologia , Doença das Coronárias/complicações , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/tratamento farmacológico , Humanos , Infusões Intra-Arteriais , RadiografiaAssuntos
Doenças Cardiovasculares/terapia , Adulto , Angioplastia com Balão , Arteriosclerose/terapia , Cardiomiopatia Hipertrófica/complicações , Cardiomiopatia Hipertrófica/tratamento farmacológico , Cardiomiopatia Hipertrófica/cirurgia , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/cirurgia , Feminino , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Infusões Intra-Arteriais , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/complicações , Insuficiência da Valva Mitral/cirurgia , Infarto do Miocárdio/tratamento farmacológico , Revascularização Miocárdica , Obstrução da Artéria Renal/terapia , Estreptoquinase/administração & dosagem , Vasodilatadores/administração & dosagemRESUMO
The proximal segments of the left coronary artery are foreshortended in the usual projections. By additional cranio-caudal (half axial) projections the X-ray beam can be directed perpendicular to these segments. In some patients lesions especially of the left main coronary artery or the proximal LAD can be seen or accurately evaluated only in the half axial projection, as demonstrated by examples. The clinical implications are discussed.
Assuntos
Angiocardiografia/métodos , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagemRESUMO
To estimate the stray radiation exposure which will be delivered to the doctor during a coronary angiography we made phantom measurements. The dependence of the stray radiation from the projection angle as well as from the tube tension for fluoroscopy and cinematography was measured in the three space coordinates. Out of these results the exposure per examination can be estimated for each place and hight of the doctor. As an example a determination of exposure under practical condition as well as the means of radiation protection are discussed.
Assuntos
Cardiologia , Espalhamento de Radiação , Angiografia , Animais , Angiografia Coronária , Matemática , Doses de Radiação , Proteção RadiológicaRESUMO
A brief description of recanalization of the thrombotic coronary artery is provided, including the historical background and our own first experience of recanalization during the event of an acute catheter complication. Mechanical recanalization of occluded coronary arteries as initially performed by us is described. The subsequent use of intracoronary infusion of streptokinase is also detailed. An account is given of the angiographic and clinical results in a study of 59 patients. We then consider the encountered and potential complications of percutaneous transluminal coronary artery recanalization (PTCR) based on a study of 232 acute infarction patients treated in four different centers. A discussion of the potential benefits of the intervention is provided, including lower mortality in a patient subgroup that underwent successful recanalization, as well as improved left ventricular function as seen angiographically in successfully recanalized patients. Use of intracoronary thallium injections before and after recanalization is discussed. It is stated that precise delineation of efforts will require randomized control trials. Finally, we provide some suggestions as to the potential follow-up treatment and future development of the technique.
Assuntos
Angioplastia com Balão/métodos , Vasos Coronários , Infarto do Miocárdio/terapia , Estreptoquinase/uso terapêutico , Anticoagulantes/uso terapêutico , Humanos , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/cirurgia , Revascularização Miocárdica/métodosRESUMO
Ergometric and coronary angiographic findings were compared in 145 patients with proximal lesions of at least 50% of major coronary arteries. 75% of the patients had had a previous myocardial infarction. The following ergometric parameters occur most frequently in 3-vessel disease. (1) coronary insufficiency persisting after myocardial infarction, (2) ST-segment depression of at least 0.2 mV, (3) maximum exercise tolerance limited to less than 75 Watts. However, these parameters cannot predict 3-vessel disease with absolute certainty, nor can they exclude a single vessel disease. 3-vessel disease is not likely, if there is a maximum heart rate of 150 beats per minute or more. There were only slight differences between patients with 1-vessel disease and patients with 2-vessel disease. Patients who were limited at the 50 Watts level were found to have significant LAD disease, either alone or in combination with other vessels, with the exception of one patient.
Assuntos
Doença das Coronárias/fisiopatologia , Teste de Esforço , Adulto , Idoso , Angiocardiografia , Doença das Coronárias/diagnóstico , Doença das Coronárias/patologia , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Left ventricular filling pressure and cardiac output (C.O.) were studied at rest and during exercise in 145 patients with severe coronary artery disease, i.e. narrowing of at least one major coronary artery of greater than or equal to 50%. 95% of these patients had had a previous myocardial infarction. The most important findings are as follows: (1) Inappropriate C.O. at rest and during exercise indicates multiple vessel disease in most cases. (2) Marked increase of filling pressure during exercise indicates multiple vessel disease in most cases. (3) PCP during exercise is higher in patients with LAD disease (isolated or in combination with additional lesions), than in patients with RCA and/or left CX involvement.
Assuntos
Doença das Coronárias/fisiopatologia , Hemodinâmica , Arteriosclerose/diagnóstico , Pressão Sanguínea , Capilares/fisiopatologia , Cateterismo Cardíaco , Débito Cardíaco , Humanos , Infarto do Miocárdio/fisiopatologia , Esforço Físico , Circulação Pulmonar , Resistência VascularRESUMO
Streptokinase, 1000-2000 U/h, was administered into the coronary artery via catheter over 15-60 minutes to 12 patients. Six of them had an infarct in the early stage (A), two a fresh re-infarction (B) and four nonstable angina (C). Nitroglycerine had been injected at a dose of 0.1-0.45 mg into the coronary artery before infusion of streptokinase. Nitroglycerine induced angiographic demonstrably better filling of the infarcted vessel in two patients of group A. After intracoronary injection of streptokinase the occluded artery re-opened or, if there had been subtotal stenosis, significantly widened in all patients of group A. But there was no complete disappearance of the narrowing. In the patients of group B and C there was no angiographic evidence of change, neither after nitroglycerine nor after streptokinase. There was no marked change in systemic clotting function. The findings indicate that after acute, first-time infarction a fresh coronary thrombus forms on the basis of atheromatous narrowing. The thrombus can be quickly removed by selective lysis via coronary catheter. Fresh thrombotic deposition is less likely on re-infarction or in nonstable angina. These results must be confirmed by observation on a larger group of patients.