RESUMO
The central action of platelets in pathophysiology of Acute Coronary Syndromes (ACS) has been outlined in relation to activation, inflammation and distal embolization. This platelet activation in ACS, plays the protagonistic role in the coronary artery thrombosis as the initial ischemic event, as well as in regards to its recurrence. The glycoprotein IIb/IIIa (GP IIb/IIIa) receptor is critical in this process. The introduction of this new class of drugs in the treatment of ACS has become a new tool in the initial treatment of the three main scenarios (elective intervention coronary procedures, unstable angina and acute myocardial infarction without ST elevation, and acute myocardial infarction either primary percutaneous angioplasty or in combination of low doses of thrombolytic agents) of this syndromes. This paper describes the indication and doses of the three commercially available GP IIb/IIIa inhibitors and describe the group of patients who are not candidates for this strategy.
Assuntos
Doença das Coronárias/tratamento farmacológico , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Doença Aguda , Humanos , Infarto do Miocárdio/tratamento farmacológico , Síndrome , Fatores de TempoRESUMO
UNLABELLED: To obtain more information about the role of the pericardium in the setting of acute right ventricular infarction (ARVI) we studied the behaviour of the ventricular function curves (VFC) and the relationship of the ventricular end-diastolic pressures (R-VEDP-RV:LV) in two groups of dogs. Group A. (n = 12) Control (C), ARVI, Pericardiectomy (P). A parabolic behaviour of the C VFC was noted (r2 = 071) and it's flexion point (FP) was found in 13. +/- 2 mmHg. After the ARVI the right (R) VFC was shifted downwards and to the right and the FP was documented in 18 +/- 2 mmHg (p < 0.05) in relation to C VFC. After P the RVFC was displaced upwards and to the left in relation to ARVIC RVFC (p < 0.05). The C R-VEDP-RV:LV = 0.75 and only a trend to equalization after the ARVI and after P were noted (0.91, 0.84, respectively) (p = ns). Group B (n = 12). Control (C), P, ARVI. The RVFC after P was shifted up and to the left in relation to the C RVFC (p < 0.05) and the FP = 10 +/- 2 mmHg. After P in the setting of ARVI the RVFC was shifted downward and to the right in relation to P RVFC (p < 0.05). After P the R-VEDP-RV:LV = 0.45 and statistical significant equalized in the condition of ARVI without pericardium (0.95, p < 0.05). CONCLUSION: Ours results support a partial restrictive role of the pericardium in the origin of the low cardiac output (LCO) in ARVI. Because, equalization of the R-VEDP-RV:LV is not only due to the restraining pericardial effect but is also due to right ventricular myocardial ischemia. The FP (18. +/- 2 mmHg) found seems to be the top value of RVEDP for volume infusion in experimental ARVI. Hemodynamic finding that could be useful in the preload volume management for humans with ARVI and LCO or systemic hypotension.
Assuntos
Infarto do Miocárdio/fisiopatologia , Pericárdio/fisiopatologia , Disfunção Ventricular Direita/fisiopatologia , Animais , Cães , Feminino , Masculino , Modelos Cardiovasculares , PericardiectomiaRESUMO
Simultaneous right and left ventricular function curves (VFC, R, L) were obtained in a canine model, (open chest preparation), with and without pericardium. Preload and afterload conditions for the right and left ventricles were controlled. VFC were constructed from zero to 25 mmHg of ventricular end-diastolic pressures and by increasing the cardiac output from 50 to 250 mL/kg-1min-1. Both, right and left VFC showed an initial steep rise at low filling pressures and then flattened off to a plateau at high filling pressures. The best mathematical model that fitted with the VFC, with and without the pericardium was the parabola (r2 = 0.71, 0.72 respectively). After pericardiectomy R and L VFC were displaced to the left of the VFC with pericardium and a decrease in filling pressures were noted at the same points of cardiac output, findings that suggest a restraining effect of the pericardium. By subtracting the filling pressures obtained with pericardium from those without pericardium at the same levels of cardiac output, pericardial pressures were derived. In all the range of the VFC the pericardial pressures were positive, and this pressure increase as cardiac output increase. Thus the transmural pressure was never cero, for both right and left ventricles. The observed relation for the R and L filling pressures, derived from a polynomial equation of second order suggest a small although not unimportant effect of the pericardium at normal filling pressures, and a very substantial influence at high levels of cardiac output. The demarcation between small and major effects appears in the upper range of normal filling pressures in this dynamic approach of the pericardial pressures.
Assuntos
Pericárdio/fisiologia , Função Ventricular Esquerda/fisiologia , Função Ventricular Direita/fisiologia , Pressão Ventricular/fisiologia , Algoritmos , Animais , Cães , Feminino , Masculino , Pericárdio/cirurgiaRESUMO
UNLABELLED: We studied 398 patients with diagnosis of acute myocardial infarction who arrived within the first six hours of symptom onset that were treated with thrombolysis or primary angioplasty, they were divided in two groups: Group 1 (n = 198), those treated with 1.5 million U of streptokinase over 60 min and Group 2 (n = 200), those treated with primary angioplasty. In Group 1 the "pain-door" time was 3.7 +/- 1.7 hs vs 3.8 +/- 2.4 hs in group 2 (p = NS). The "door-needle" time was 48 +/- 12 min. compared with the "door-balloon" time of 84 +/- 30 min (p < 0.001). In Group 1, 154 (77.6%) of the patients had clinical of reperfusion after thrombolysis, 58 of them underwent coronary angiography and had an infarct related artery (IRA) patency rate of 45.3%. In Group 2 the IRA patency rate was 85.5% (p < 0.005). CONCLUSION: Thrombolysis was achieved in a lesser period of time but our findings showed that primary angioplasty was more effective obtaining a TIMI 3 flow.
Assuntos
Angioplastia , Fibrinolíticos/uso terapêutico , Infarto do Miocárdio/terapia , Reperfusão Miocárdica , Estreptoquinase/uso terapêutico , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/cirurgia , Fatores de TempoRESUMO
The objective of our study was to validate the diagnostic utility of cardiac troponine T in acute ischemic syndromes, and also in cases of difficult diagnosis. We analyzed its concordance and compare them with conventional enzymatic quantitative methods. We determined sensitivity, specificity, positive and negative predictive values and likelihood ratio. Kappa index was used to know the concordance grade between T troponin and the positive or negative results of the quantitative enzymatic curve. Stochastic significance was valued by Chi square of Mcnemar test. In seventy patients who arrived to the hospital with chest pain who were assigned to five different groups. The sensitivity in quantitative markers was higher than qualitative methods, however the specificity, likelihood ratio was lower. In the total group the concordance analysis between qualitative and quantitative markers was adequate, (kappa index 0.65 p < 0.05). This study suggest that the rapid bedside qualitative test by cardiac Troponin T is a good diagnostic marker compared with conventional quantitative markers to evaluate chest pain in acute ischemic syndromes.
Assuntos
Creatina Quinase/análise , Isquemia Miocárdica/diagnóstico , Miocárdio/metabolismo , Mioglobina/análise , Sistemas Automatizados de Assistência Junto ao Leito , Troponina T/análise , Doença Aguda , Ensaios Enzimáticos Clínicos , Feminino , Humanos , Isoenzimas , Masculino , Pessoa de Meia-Idade , Miocárdio/enzimologiaRESUMO
OBJECTIVE: To review the results and complications of thrombolysis in patients with acute myocardial infarction (AMI) and its complications. METHODS: Since june 1989 to august 1994 we studied patients with AMI, who underwent thrombolysis. Clinical characteristics, complications and angiographic results are described. RESULTS: Of the total population 86.3% patients received Streptokinase (SK) and 13.7% recombinant tissue plasminogen activator (rt-PA). In 20 patients the age was under 40 years, 373 between 40-70 years, and 80 patients over 70 years. 84% were men and 16% women. 72% had smoking habit; 21% diabetes mellitus, 43% hypertension, 54% had previous angina and previous AMI in 22%. The location of AMI was anterior in 234 patients and 239 inferior. In 63% enzyme washout was observed, and rapid electrocardiographic evolution in 81%. Postthrombolisis arrhythmias was observed in 64.7%. Major bleeding in 11.8% and central nervous system hemorrhage in 0.4% only with rt-PA. Postinfarction angina in 22%, and re-infarction in 4%. Cardiac rupture in 1.4%, with shock and death. Mitral insufficiency in 2.1% demonstrated by echocardiogram. Coronary angiography was done in 373 patients (80%), of which 50.7% was made in the first 5 days. The culprit artery was anterior descending in 273 patients and right coronary in 95. Left ventricular dysfunction was seen in 23% in patients with anterior AMI, and 5% with inferior AMI. Cardiogenic shock was seen in 7%. Coronary artery bypass grafting was undertaken in 106 patients and coronary angioplasty in 67. The ten days mortality was 8.8%, principally due to cardiogenic shock, ventricular arrhythmias and ventricular rupture. CONCLUSIONS: The usefull permeability in the culprit artery was obtained in 40%, who had coronary angiography done 145 hours posthrombolysis. Mortality was under 10% in this study.
Assuntos
Infarto do Miocárdio/tratamento farmacológico , Ativadores de Plasminogênio/uso terapêutico , Proteínas Recombinantes/uso terapêutico , Estreptoquinase/uso terapêutico , Terapia Trombolítica , Doença Aguda , Adulto , Idoso , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: To analyze the role of the culprit coronary artery in myocardial infarction, its evolution and mortality. And to correlate with clinical criteria of reperfussion. MATERIALS AND METHODS: We included patients with clinical diagnosis of acute myocardial infarction (MI) treated with thrombolytic therapy, and coronariography. We used the TIMI study angiographic scale to evaluate the level of permeability of the culprit artery. RESULTS: Of 473 patients with of acute MI; coronariography was made in 377. The most frequent culprit vessel was anterior descending artery in 168 patients (45%) and right coronary artery in 139 patients (36%). In 276 patients the culprit vessel was permeable (73%). Of them in 30 patients, had TIMI 1 alterations, TIMI 2 in 97 patients, had TIMI 3 in 148 patients, only 102 patients had TIMI 0. In anterior MI the most frequent reperfussion arrhythmia was ventricular ectopic beats followed by slow ventricular tachycardia and ventricular tachycardia in 54%, ventricular fibrillation was observed only in six patients, of whom TIMI scale was 2 and 3 in five patients. In inferior MI, ventricular ectopic beats and slow ventricular tachycardia was seen in 25% of patients. In patients with permeable culprit artery we observed significant depression of ST segment, (159 patients, 42%), and significant increase in CK-MB levels, seen in 191 patients (51%). In the group of patients with total occlusion of the culprit artery, twenty-one (30%) had left ventricular disfuntion, and only six of them were in cardiogenic shock. In the group of patients with permeable culprit artery only two percent had cardiogenic shock. Therefore the analysis of the clinical evolution is the maia marker to take into consideration to send patients to early coronary arteriography with the objective to look for other therapeutic alternatives.