RESUMO
The practice of percutaneous transluminal coronary angioplasty has shown that the major complications are acute dissection as well as suboptimal results and restenosis. The effort to reduce these complications has led to create an intravascular device called Stent. The technology is complex and very expensive, for this reason we designed and made a new model of stent named SAQ. We introduce: The methodology of development, fabrication and modifications of a new intravascular device Stent SAQ. The results obtained in coronary arteries of ex vivo hearts of pigs and humans. The results in two model of animals, rabbit aorta and peripheral arteries in dogs. This investigation at this phase, shows satisfactory properties of SAQ which is secure and effective, with similar properties to the stents in use.
Assuntos
Angioplastia Coronária com Balão , Doença da Artéria Coronariana/cirurgia , Stents , Animais , Cães , Coelhos , Prevenção SecundáriaRESUMO
The occurrence of myocardial infarction during a pregnancy is rare event and it is even less frequent during the puerperium. The literature reports only 23 cases of myocardial infarction during the puerperium. We report a case of a woman of 26 years of age without coronary risk factors, who on the seventh day postpartum presented an acute myocardial infarction of the anterior and lateral walls. On the ninth day postpartum by means of cardiac catheterization we were able to demonstrate the presence of normal coronary arteries and a left ventricular ejection fraction of 50%. Laboratory and other diagnostic tests did not demonstrate the presence of known etiological factors associated with myocardial infarction.
Assuntos
Infarto do Miocárdio/diagnóstico , Transtornos Puerperais/diagnóstico , Adulto , Cateterismo Cardíaco , Ensaios Enzimáticos Clínicos , Angiografia Coronária , Eletrocardiografia , Feminino , Coração/diagnóstico por imagem , Humanos , Cintilografia , Pirofosfato de Tecnécio Tc 99mRESUMO
The efficacy of any method of transluminal angioplasty has been evaluated with angiography, this can show the major anatomic results. Angioscopy can detect by direct observation, the induced changes in the vessel wall morphology after the recanalization method. We studied 5 coronary arteries and 9 peripheral arteries with total occlusion in 7, and the other 7 with more than 75% of obstruction. All of them were evaluated with angiography and angioscopy, before and after the transluminal angioplasty. Eleven of the arteries were treated by transluminal ultrasound angioplasty, we obtained recanalization in 90% of them, in 6 (55%) of this we found angioscopic evidence of dissection in variable degrees. Two cases were treated only with balloon angioplasty, and the angioscopy image was of dissection too. In the only case of laser angioplasty we observed dark brown coloration in the treated lesion suggesting carbonization changes. The initial angiography analysis did not suggest the presence of complication of the atheroma plaque. However in 21% of the cases the angioscopy inspection demonstrated and hemorrhagic dye of the endothelium, and thrombosis in situ in 29%. We no found correlation in angiography and angioscopy aspect in 25% of the cases. Some of the endothelial alterations that can not be detectable by angiography, can be demonstrated by angioscopy, this changes could improve the appreciation of any recanalization method results, that could suggest its possible immediate and late complications.
Assuntos
Artérias/patologia , Vasos Coronários/patologia , Angioplastia com Balão/instrumentação , Angioplastia a Laser/instrumentação , Angiografia Coronária , Doença das Coronárias/diagnóstico , Doença das Coronárias/terapia , Endoscópios , Estudos de Avaliação como Assunto , Tecnologia de Fibra Óptica/instrumentação , Humanos , Doenças Vasculares Periféricas/diagnóstico , Doenças Vasculares Periféricas/terapia , Terapia por Ultrassom/instrumentaçãoRESUMO
The risk of suddenly presenting ventricular tachyarrhythmias or death was analyzed in a prospective way in 71 patients with acute myocardial infarction and in 21 patients without any apparent cardiopathy. The average surface signal was measured when the patient was admitted in the hospital and on the following days of the acute phase of the infarction. Holter 24 hours monitoring and determination of the ejection fraction with radionuclide angiocardiography were also performed. Patients were divided into 4 groups, depending on the existence of arrhythmias and if late electric activity was recorded or not. Fifty-five patients (group I), presented an abnormal signal analysis (voltage in the 40 msec of the QRS period higher than 20 microvolts), and ventricular arrhythmias. Group II was formed by 8 patients who presented arrhythmogenic activity but did not present late electric activity. Group III was formed by 6 patients who did not present arrhythmias but presented late electric activity. Twenty-three patients who did not present late electric activity or ventricular arrhythmias formed group IV. Late electric activity that was registered at 41 +/- 1 msec with a QRS complex lasting 115 +/- 4 msec and with a voltage lower than 20 microvolts in group I showed meaningful differences with the other groups: Group II: (24 +/- 5 msec, QRS 111 +/- 4 msec, P less than 0.001); Group III: (41 +/- 2 msec, QRS 109 +/- 5 msec, P less than 0.01); Group IV: (26 +/- 5 msec, QRS 80 +/- 7 msec, P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Arritmias Cardíacas/fisiopatologia , Infarto do Miocárdio/fisiopatologia , Adulto , Idoso , Arritmias Cardíacas/complicações , Morte Súbita/etiologia , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Fatores de TempoRESUMO
The application of ultrasonic energy for ablation of atherosclerotic plaques was studied. This study was performed in 92 segments obtained from human coronary arteries which belonged to eleven hearts obtained from patients who have died from acute myocardial infarction. An ultrasound generating system (Cavitron 600) was used, and an ultrasonic probe wire (P-150 Endosonic), was attached to it. A stainless steel wire (0.36 mm in width and 145 cm length), was fixed to this probe. Sonic pulsed stimulations 20 sec long and 25 kHz in frequency were performed. The sound transmitting characteristics of the angioplasty guide wire were studied, as well as the ultrasound effects upon atherosclerotic plaques, blood elements, coagulation, and it's lysis effects upon recently formed clots. The anatomic pieces were filmed in cineangiocoronary graphy in two planes, anterior right oblique an anterior left oblique, to be studied later under light microscopy. The results were as following: in the 100% obstructions, a 41% recanalization was obtained; in the 95% obstructions, a 79%, in the 75% obstructions, a 37%. We did not work in the 50% or less obstructions. Under the procedure, no artery suffered perforations. Under Light microscopy, a plaque fragmentation was observed in 24% of the cases; rupture and fragmentation, in 14%, cavitations in 10%; ondulations in 9%; plaque rupture and thermic lesion in 8%; 22% did not present changes. The collected detritus had 110 +/- microns diameter. Erythrocytes exposed to 30 or 60 sec of ultrasound were found to present crenocytosis, central cavitation, hypochromia, and poikilocytosis; these ones exposed less than 22 sec did not show changes. The fibrinogen levels after the application of ultrasound were 19% lower. Coagulation time did not change with exposure 20 sec long at 20 kHs. The angioplasty guide wires attenuation coefficients were: with the guide wire outside the Miller's catheter, 44%; and with the guide wires inside, 65%. Coronary transluminal angiosonoplasty is a new interventionist technic designed to remodel an obstructive lesion of the coronary arteries, in order to diminish or nullify the obstruction. It's clinic use in the acute myocardial infarction, as a mechanical method to achieve clot's lysis, could be an alternative or a co-helper therapeutics to thrombolysis.