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1.
J Am Coll Cardiol ; 22(3): 714-9, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8354803

RESUMO

OBJECTIVES: This study was undertaken to determine whether early successful thrombolysis can reverse infarct-associated mitral valve dysfunction. BACKGROUND: Mitral regurgitation is a common complication of acute myocardial infarction and has been shown to adversely affect both short- and long-term prognosis. Although anecdotal reports have suggested that reperfusion of the infarct-related artery may restore normal function to the mitral valve, this theory has not been subjected to formal investigation. METHODS: Patients with total or partial obstruction of the infarct-related artery received intravenous thrombolytic therapy with either streptokinase or recombinant tissue-type plasminogen activator within 7 h of symptom onset (mean 4.8 h) as part of the Thrombolysis in Myocardial Infarction (TIMI) Phase I trial. Repeat coronary angiography assessed arterial patency at 90 min and 10 days after attempted reperfusion. The presence and severity of mitral regurgitation were determined by contrast ventriculography both before thrombolysis and before hospital discharge. RESULTS: Overall, 21 (16%) of the 132 study patients exhibited mitral regurgitation on either their initial or their predischarge ventriculogram. The proportion of infarct-related arteries found to be patent (TIMI flow grade 2 or 3) was statistically similar in patients with and without mitral regurgitation during each angiographic evaluation period (initial, 90 min and 10 days). Although coronary artery perfusion increased overall during sequential measurement (mean TIMI grade was 0.4 +/- 0.6 initially, 1.5 +/- 1.3 at 90 min and 2.2 +/- 1.0 at 10 days), the pattern of reperfusion observed could not predict an increase or decrease in regurgitant severity (p = NS). Early mitral regurgitation resolved in 57% of patients by 10 days, but this resolution appeared independent of the presence or absence of improved coronary perfusion (60% vs. 50%). The development of new regurgitation during the recovery period (6%) was also unrelated to improved perfusion (7% vs. 4%). CONCLUSIONS: Acute mitral regurgitation developing during myocardial infarction shows frequent changes in its presence or severity during the 1st 10 days, appears independent of coronary artery patency both early and late after thrombolysis and cannot be reliably treated by improving arterial perfusion with thrombolytic agents.


Assuntos
Insuficiência da Valva Mitral/tratamento farmacológico , Infarto do Miocárdio/tratamento farmacológico , Terapia Trombolítica , Doença Aguda , Adulto , Idoso , Análise de Variância , Cateterismo Cardíaco , Distribuição de Qui-Quadrado , Angiografia Coronária , Feminino , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/epidemiologia , Insuficiência da Valva Mitral/etiologia , Infarto do Miocárdio/complicações , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/epidemiologia , Proteínas Recombinantes/uso terapêutico , Terapia Trombolítica/estatística & dados numéricos , Ativador de Plasminogênio Tecidual/uso terapêutico
2.
Circulation ; 86(1): 232-46, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1535570

RESUMO

BACKGROUND: Precise knowledge of the expected "normal" lumen diameter at a given coronary anatomic location is a first step toward developing a quantitative estimate of coronary disease severity that could be more useful than the traditional "percent stenosis." METHODS AND RESULTS: Eighty-three arteriograms were carefully selected from among 9,160 consecutive studies for their smooth lumen borders indicating freedom from atherosclerotic disease. Of these, 60 men and 10 women had no abnormalities of cardiac function, seven men had idiopathic dilated cardiomyopathy, and six men had left ventricular hypertrophy associated with significant aortic stenosis. Lumen diameter was measured at 96 points in 32 defined coronary segments or major branches. Measurements were scaled to the catheter, corrected for imaging distortion, and had a mean repeat measurement error of 0.12 mm. When sex, anatomic dominance, and branch length were accounted for, normal lumen diameter at each of the standard anatomic points could usually be specified with a population variance of +/- 0.6 mm or less (SD) and coefficient of variation of less than 0.25 (SD/mean). For example, the left main artery measured 4.5 +/- 0.5 mm, the proximal left anterior descending coronary artery (LAD) 3.7 +/- 0.4 mm, and the distal LAD 1.9 +/- 0.4 mm. For the LAD, lumen diameter was not affected by anatomic dominance (right versus left), but for the right coronary artery, proximal diameter varied between 3.9 +/- 0.6 and 2.8 +/- 0.5 mm (p less than 0.01) and for the left circumflex, between 3.4 +/- 0.5 and 4.2 +/- 0.6 mm (p less than 0.01). Women had smaller epicardial arterial diameter than men (-9%; p less than 0.001), even after normalization for body surface area (p less than 0.01). Branch artery caliber was unaffected by the anatomic dominance but increased with branch length, expressed as a fraction of the origin-to-apex distance (p less than 0.001). Lumen diameter was not affected by age or by vessel tortuosity but was significantly increased among men with left ventricular hypertrophy (+ 17%; p less than 0.001) or dilated cardiomyopathy (+ 12%; p less than 0.001). CONCLUSIONS: This is a reference normal data set against which to compare lumen dimensions in various pathological states. It should be of particular value in the investigation of diffuse atherosclerotic disease.


Assuntos
Envelhecimento/fisiologia , Angiografia Coronária , Cardiopatias/diagnóstico por imagem , Caracteres Sexuais , Adulto , Cardiomegalia/diagnóstico por imagem , Cardiomiopatia Dilatada/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Modelos Cardiovasculares , Valores de Referência , Reprodutibilidade dos Testes
3.
Ann Intern Med ; 117(1): 10-7, 1992 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-1596042

RESUMO

OBJECTIVE: To investigate mitral regurgitation occurring early in the course of acute myocardial infarction with respect to its incidence, the impact of infarct size and location, the accuracy of clinical detection, the contribution of global and regional left ventricular performance, and its influence on prognosis. DESIGN: Prospective observational study derived from patients entering Phase I of the Thrombolysis in Myocardial Infarction (TIMI) trial. SETTING: Multicenter trial involving 13 university-affiliated medical centers. PATIENTS: A total of 206 patients studied within 7 hours of symptom onset during their first myocardial infarction. MEASUREMENTS: Contrast left ventriculography was used to document mitral regurgitation. RESULTS: Mitral regurgitation was present in 27 patients (13%). Although the presence of regurgitation correlated with the site of infarction (20 of 27 had anterior infarctions) and the number of akinetic chords, it was not statistically related to the peak creatine kinase value or to left ventricular chamber size or filling pressure. A murmur of mitral regurgitation was heard in only 2 patients (1 incorrectly). The presence of early mitral regurgitation predicted cardiovascular mortality at 1 year by univariate (relative risk, 12.2; 95% Cl, 3.5 to 42; P less than 0.0001) and multivariate (relative risk, 7.5; Cl, 2.0 to 28.6; P = 0.0008) analyses. CONCLUSIONS: Mitral regurgitation in early myocardial infarction is generally clinically "silent," is more common in anterior infarction, is associated with regional dysfunction but not early ventricular dilation or peak enzyme release, and is an important predictor of cardiovascular mortality.


Assuntos
Insuficiência da Valva Mitral/etiologia , Infarto do Miocárdio/complicações , Adulto , Idoso , Cinerradiografia , Feminino , Seguimentos , Auscultação Cardíaca , Ventrículos do Coração/diagnóstico por imagem , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/diagnóstico , Insuficiência da Valva Mitral/epidemiologia , Insuficiência da Valva Mitral/mortalidade , Infarto do Miocárdio/mortalidade , Prognóstico , Análise de Regressão , Taxa de Sobrevida , Fatores de Tempo
4.
N Engl J Med ; 323(19): 1289-98, 1990 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-2215615

RESUMO

BACKGROUND AND METHODS: The effect of intensive lipid-lowering therapy on coronary atherosclerosis among men at high risk for cardiovascular events was assessed by quantitative arteriography. Of 146 men no more than 62 years of age who had apolipoprotein B levels greater than or equal to 125 mg per deciliter, documented coronary artery disease, and a family history of vascular disease, 120 completed the 2 1/2-year double-blind study, which included arteriography at base line and after treatment. Patients were given dietary counseling and were randomly assigned to one of three treatments: lovastatin (20 mg twice a day) and colestipol (10 g three times a day); niacin (1 g four times a day) and colestipol (10 g three times a day); or conventional therapy with placebo (or colestipol if the low-density lipoprotein [LDL] cholesterol level was elevated). RESULTS: The levels of LDL and high-density lipoprotein (HDL) cholesterol changed only slightly in the conventional-therapy group (mean changes, -7 and +5 percent, respectively), but more substantially among patients treated with lovastatin and colestipol (-46 and +15 percent) or niacin and colestipol (-32 and +43 percent). In the conventional-therapy group, 46 percent of the patients had definite lesion progression (and no regression) in at least one of nine proximal coronary segments; regression was the only change in 11 percent. By comparison, progression (as the only change) was less frequent among patients who received lovastatin and colestipol (21 percent) and those who received niacin and colestipol (25 percent), and regression was more frequent (lovastatin and colestipol, 32 percent; niacin and colestipol, 39 percent; P less than 0.005). Multivariate analysis indicated that a reduction in the level of apolipoprotein B (or LDL cholesterol) and in systolic blood pressure, and an increase in HDL cholesterol correlated independently with regression of coronary lesions. Clinical events (death, myocardial infarction, or revascularization for worsening symptoms) occurred in 10 of 52 patients assigned to conventional therapy, as compared with 3 of 46 assigned to receive lovastatin and colestipol and 2 of 48 assigned to receive niacin and colestipol (relative risk of an event during intensive treatment, 0.27; 95 percent confidence interval, 0.10 to 0.77). CONCLUSIONS: In men with coronary artery disease who were at high risk for cardiovascular events, intensive lipid-lowering therapy reduced the frequency of progression of coronary lesions, increased the frequency of regression, and reduced the incidence of cardiovascular events.


Assuntos
Apolipoproteínas B/sangue , Colestipol/administração & dosagem , Doença das Coronárias/tratamento farmacológico , Lovastatina/administração & dosagem , Adulto , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Colestipol/uso terapêutico , Angiografia Coronária , Doença das Coronárias/sangue , Dieta , Método Duplo-Cego , Quimioterapia Combinada , Humanos , Lovastatina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Niacina/administração & dosagem , Niacina/uso terapêutico
5.
Am J Cardiol ; 63(9): 503-12, 1989 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-2521976

RESUMO

Before commencing the randomized Thrombolysis in Myocardial Infarction phase II (TIMI II) study, 370 patients were administered intravenous recombinant tissue plasminogen activator (rt-PA) within 4 hours of onset of acute myocardial infarction (AMI) and assigned to 2-hour (immediate) percutaneous transluminal angioplasty (n = 33), 18- to 48-hour (delayed) angioplasty (n = 288) or no angioplasty (n = 49) in a nonrandomized, observational pilot study. Left ventricular ejection fraction at rest and during exercise was assessed by gated equilibrium radionuclide ventriculography at hospital discharge and again at 6 weeks. At hospital discharge, ejection fraction averaged 50% at rest and 56% at peak exercise. At 6-week follow-up, ejection fraction averaged 50% at rest and 53% at peak exercise. At 6-week follow-up, resting ejection fraction average 49% in the 2-hour angioplasty group, 49% in the 18- to 48-hour angioplasty group and 55% in the no-angioplasty group. Variables independently predicting "good functional outcome" at 6-week follow-up (survival with resting ejection fraction greater than equal to 50% and no decrease with exercise) in the 18- to 48-hour angioplasty group were fewer leads with ST-segment elevation greater than or equal to 0.1 mV, younger age, rapid normalization during rt-PA infusion of ST segments or dramatic relief of chest pain, absence of arrhythmias within the first 24 hours of treatment initiation, no prior infarction and not a cigarette smoker at entry. Thus, the TIMI II pilot study demonstrates that most patients with AMI of less than or equal to 4-hour duration treated with rt-PA have good ventricular function after AMI.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Angioplastia com Balão , Infarto do Miocárdio/terapia , Ativador de Plasminogênio Tecidual/uso terapêutico , Angiografia , Angiografia Coronária , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Infarto do Miocárdio/fisiopatologia , Reperfusão Miocárdica , Projetos Piloto , Distribuição Aleatória , Proteínas Recombinantes/uso terapêutico , Volume Sistólico , Fatores de Tempo
6.
Arteriosclerosis ; 9(1 Suppl): I81-90, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2912435

RESUMO

A computer-assisted method for quantitatively assessing progression and regression of coronary atherosclerosis has been applied, in a fully blinded fashion, to a set of 116 5-year-interval coronary arteriograms obtained between 1972 and 1981 in the National Heart, Lung, and Blood Institute (NHLBI) Type II Study. Coronary changes are described in 54 of these patients who had tendinous xanthomata and hypercholesterolemia consistent with the diagnosis of familial hypercholesterolemia. Among 468 patent lesions of all degrees of severity and among 25 total occlusions identified on the initial arteriogram, 11% progressed by the 95% confidence criterion for assessing change in percent stenosis (+/- 17%), and 1% regressed by using the same criterion. Among 54 patients, 50% had progression only, 6% had regression only, and 4% had mixed progression and regression. Because half of these patients were treated with cholestyramine, these frequencies may underestimate the natural history of their disease progression. Comparable frequencies were obtained by using the 95% confidence criterion for change in stenosis resistance (Rp ratio outside range, 0.35 to 2.9). In properly obtained arteriograms, the Rp parameter is physiologically relevant and is a sensitive index of lesion change with a high signal-to-noise ratio; we advocate its use for detection of progression and regression. Morphologic features, including luminal irregularity and ulceration, increased the likelihood of progression by 1.8- to 5-fold. Surprisingly, significant arterial flexing at the site of the lesion predicted anatomic stability. A lumen narrowed by visible thrombus was 100-fold more likely to regress than were those without it. The initial severity of stenosis correlated strongly with new total occulusion and with disease progression as assessed by Rp change. Because lesion-specific features are important determinants of lesion change, intervention trials that statistically account for the contributions of lesion morphology are likely to provide a more insightful assessment of the therapeutic benefit.


Assuntos
Doença da Artéria Coronariana/patologia , Hiperlipoproteinemia Tipo II/patologia , Angiografia , Heterozigoto , Humanos , Hiperlipoproteinemia Tipo II/genética , Interpretação de Imagem Radiográfica Assistida por Computador , Fatores de Tempo
8.
Circulation ; 78(5 Pt 1): 1167-80, 1988 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3180376

RESUMO

The clinically important coronary segmental anatomy has been described in a format useful for quantitative analysis and standardized display. We have determined the intrathoracic location and course of each of the 23 coronary artery segments and branches commonly used for clinical description of disease. Measurements were averaged from perpendicular angiographic view-pairs in 37 patients with normal-sized hearts. Each segment or branch is described by several points along its course; each point is specified in polar coordinates as the radial distance from the principal coronary ostium and by angles about the patient, corresponding to those describing rotation in c-arm radiographic systems. This computer-assisted measurement method is accurate to within +/- 0.2 cm (SD) and +/- 2 degrees in phantom studies. Coronary segment location among a group of normal-sized hearts can be specified to within +/- 1.0 cm (SD). For example, the left anterior descending coronary artery segment at the apex of the heart is 12.2 +/- 1.0 cm from the left coronary ostium, 32 +/- 4 degrees to the left of the anterioposterior axis, and at 46 +/- 7 degrees of caudal angulation. There are several clinically important applications of this new knowledge. First, this anatomic format provides the basis for estimating regional myocardial contraction and the relative size of the myocardial region at risk from a given arterial occlusion. Second, precise knowledge of "normal" segment location greatly simplifies the computation of dimensional correction factors for quantitative arteriography. Third, viewing angles most appropriate for videodensitometric assessment of lesion lumen area may be computed from these data. The theoretical basis and numerical values needed for most of the above estimates are provided. Finally, a computer program has been written to generate a three-dimensional tree-branch vascular model from these anatomic locations. This easily used interactive program aids in teaching coronary angiographic anatomy and, of importance, permits selection of viewing angles that "best" visualize the traditionally difficult parts of the coronary tree.


Assuntos
Vasos Coronários/anatomia & histologia , Processamento de Imagem Assistida por Computador , Adulto , Idoso , Superfície Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Caracteres Sexuais
10.
J Am Coll Cardiol ; 12(2): 289-300, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3392324

RESUMO

Thrombolytic therapy for acute myocardial infarction reduces early mortality, but full recovery of left ventricular function after reperfusion is delayed. Therefore, the relations among reperfusion, survival and the time course of left ventricular functional recovery were examined in 226 patients treated with intracoronary streptokinase; 77% (134 patients) had sustained reperfusion and 31 patients had no reperfusion or had reocclusion by day 3. Wall motion was measured from contrast ventriculograms performed in the acute period and 3 days later in the central and peripheral infarct regions and the noninfarct region by the centerline method in 165 patients. Patients with reperfusion had better survival (p less than 0.05, mean follow-up 4.5 years) and a higher ejection fraction at 3 days (52 +/- 12 versus 46 +/- 10%, p less than 0.02) attributable to a significantly different change in peripheral infarct region function between the acute and 3 day studies (0.1 +/- 1.0 versus -0.3 +/- 0.9 SD, p less than 0.05). These early functional changes were significant in patients with anterior myocardial infarction and showed similar trends in those with inferior myocardial infarction. On Cox regression analysis, function measured at 3 days was more predictive of survival than was function measured acutely (chi square for acute ejection fraction = 11.48 versus 24.59 at 3 days). Although, as previously reported, greater than 45% of total recovery of left ventricular function occurs later, the ejection fraction achieved by day 3 is already predictive of survival. Thus, the mechanism by which successful thrombolytic therapy enhances survival is improvement of regional and global left ventricular function early after acute myocardial infarction.


Assuntos
Coração/fisiopatologia , Infarto do Miocárdio/tratamento farmacológico , Estreptoquinase/uso terapêutico , Circulação Coronária , Trombose Coronária/tratamento farmacológico , Trombose Coronária/fisiopatologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica/efeitos dos fármacos , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/fisiopatologia , Volume Sistólico/efeitos dos fármacos
11.
Am Heart J ; 116(1 Pt 1): 85-90, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3164977

RESUMO

Eight type III hyperlipoproteinemic (type III HLP), homozygous E 2/2 patients were enrolled in two periods of long-term diet-gemfibrozil treatment. The combined therapy resulted in highly significant decreases in their low-density lipoprotein cholesterol, very-low density lipoprotein cholesterol, very-low density lipoprotein triglycerides, and increases in their high-density lipoprotein cholesterol during the first treatment period of 24 to 28 months. Type III HLP reasserted itself following an 8-week interruption of gemfibrozil therapy. Resumption of gemfibrozil therapy again lowered the high lipid-lipoprotein concentrations of these patients toward normal. Tuboeruptive xanthomata, palmar xanthoma, and xanthoma striata palmare subsided with treatment. Follow-up coronary arteriograms performed 2.5 to 3.0 years after initiation of diet-drug treatment showed stabilization of coronary arterial lesions, which was associated with improvement in exercise tolerance.


Assuntos
Doença das Coronárias/prevenção & controle , Hiperlipoproteinemia Tipo III/tratamento farmacológico , Hipolipemiantes/uso terapêutico , Ácidos Pentanoicos/uso terapêutico , Valeratos/uso terapêutico , Adulto , Terapia Combinada , Doença das Coronárias/etiologia , Avaliação de Medicamentos , Teste de Esforço , Feminino , Genfibrozila , Dermatoses da Mão/etiologia , Dermatoses da Mão/prevenção & controle , Humanos , Hiperlipoproteinemia Tipo III/complicações , Hiperlipoproteinemia Tipo III/dietoterapia , Hipolipemiantes/efeitos adversos , Lipídeos/sangue , Lipoproteínas/sangue , Masculino , Pessoa de Meia-Idade , Ácidos Pentanoicos/efeitos adversos , Xantomatose/etiologia , Xantomatose/prevenção & controle
12.
Am J Cardiol ; 61(8): 524-9, 1988 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-3257839

RESUMO

The long-term prognosis after thrombolytic therapy in patients with acute myocardial infarction (AMI) is unknown. This question was investigated in a 4-year follow-up study of 227 patients. According to the status of reperfusion at the end of the acute catheterization, the patients were divided into a patent (n = 171) and an occluded (n = 56) group. Both hospital and 4-year mortality rates were significantly reduced in the patent group by 13 and 14%, respectively (p less than or equal to 0.005 for both). Baseline variables known to be important for prognosis did not differ between the 2 groups. Patients with a patent infarct artery who underwent early acute coronary artery bypass grafting (CABG) had a greater survival (p less than 0.10) and better left ventricular function (p less than 0.01) than did patients with a patent infarct artery who did not undergo CABG. This difference was associated with a lower frequency of fatal reinfarction and cardiogenic shock in the CABG group. Thus, survival is improved up to 4 years after successful thrombolysis and appears to be further enhanced by early CABG.


Assuntos
Fibrinolíticos/uso terapêutico , Infarto do Miocárdio/tratamento farmacológico , Cateterismo Cardíaco , Ponte de Artéria Coronária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/cirurgia , Recidiva , Volume Sistólico , Fatores de Tempo , Grau de Desobstrução Vascular
13.
Cathet Cardiovasc Diagn ; 15(2): 73-5, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3180210

RESUMO

Research collaboration between investigators located at some distance from each other is not only possible but also feasible. By using satellite-assisted computer-to-computer links, researchers across the United States and overseas work with the staff and facilities of the Cardiovascular Research and Training Center (CVRTC) in the University of Washington, Seattle. This report presents the mechanics, advantages, and results of using such an approach to collaborate with distant colleagues.


Assuntos
Doenças Cardiovasculares , Redes de Comunicação de Computadores , Sistemas Computacionais , Pesquisa , Comunicação , Bolsas de Estudo , Alemanha Ocidental , Humanos , Software , Universidades , Washington
14.
Am J Cardiol ; 60(3): 34B-38B, 1987 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-2956839

RESUMO

Coronary arteriography is the most commonly used technique for documenting the immediate percutaneous transluminal coronary angioplasty result and for follow-up of the dilated arterial segment for restenosis within 6 months (which occurs in about 25% to 35% of cases). Acute success in dilation of the coronary lesion is likely if there is at least a resultant 1.3 mm2 minimum lumen area, equivalent to a 1.3 mm mean minimum lumen diameter, or about a 50% diameter stenosis of a typical proximal vessel. The measurement methods applied to this problem include a digital caliper, computer-assisted border recognition techniques and a video-densitometric approach to estimation of lumen area. Calipers are recommended because of their simplicity, precision and accuracy for the routine assessment of angioplasty result. Border-recognition techniques require considerable operator input to distinguish true flow channels from cul de sacs in the dissected segment. The automated scanning videodensitometry approach has theoretical appeal and has shown promise in preliminary reports; however, there is the potential for large measurement errors in the setting of dissection. Further, certain qualitative morphologic features of the dilated segment, such as longitudinal or transverse dissection or intraluminal thrombus, may effectively contribute to the prediction of acute complications and may be useful predictors of late restenosis. Because these features are best appreciated at increased arteriographic magnification, further high resolution studies will be necessary to better understand their importance.


Assuntos
Angioplastia com Balão , Angiografia Coronária , Doença das Coronárias/terapia , Angiografia/métodos , Doença das Coronárias/diagnóstico por imagem , Densitometria/métodos , Seguimentos , Humanos , Recidiva
15.
Circulation ; 76(1): 142-54, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3109764

RESUMO

Intravenous administration of 80 mg of recombinant tissue plasminogen activator (rt-PA, 40, 20, and 20 mg in successive hours) and streptokinase (SK, 1.5 million units over 1 hr) was compared in a double-blind, randomized trial in 290 patients with evolving acute myocardial infarction. These patients entered the trial within 7 hr of the onset of symptoms and underwent baseline coronary arteriography before thrombolytic therapy was instituted. Ninety minutes after the start of thrombolytic therapy, occluded infarct-related arteries had opened in 62% of 113 patients in the rt-PA and 31% of 119 patients in the SK group (p less than .001). Twice as many occluded infarct-related arteries opened after rt-PA compared with SK at the time of each of seven angiograms obtained during the first 90 min after commencing thrombolytic therapy. Regardless of the time from onset of symptoms to treatment, more arteries were opened after rt-PA than SK. The reduction in circulating fibrinogen and plasminogen and the increase in circulating fibrin split products at 3 and 24 hr were significantly less in patients treated with rt-PA than in those treated with SK (p less than .001). The occurrence of bleeding events, administration of blood transfusions, and reocclusion of the infarct-related artery was comparable in the two groups. Thus, in patients with acute myocardial infarction, rt-PA elicited reperfusion in twice as many occluded infarct-related arteries as compared with SK at each of seven serial observations during the first 90 min after onset of treatment.


Assuntos
Fibrinolíticos/uso terapêutico , Infarto do Miocárdio/tratamento farmacológico , Estreptoquinase/uso terapêutico , Ativador de Plasminogênio Tecidual/uso terapêutico , Coagulação Sanguínea , Circulação Coronária , Avaliação de Medicamentos , Hemorragia/induzido quimicamente , Humanos , Injeções Intravenosas , Infarto do Miocárdio/sangue , Infarto do Miocárdio/fisiopatologia , Recidiva , Estreptoquinase/efeitos adversos , Ativador de Plasminogênio Tecidual/efeitos adversos
16.
Circulation ; 75(4): 817-29, 1987 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3103950

RESUMO

In Phase I of the NHLBI trial of Thrombolysis in Myocardial Infarction (TIMI), 290 patients admitted within 7 hr after onset of acute infarction were randomly assigned to intravenous treatment with either streptokinase (SK) or recombinant tissue-type plasminogen activator (rt-PA). Left ventricular function was measured from contrast ventriculograms in 145 patients with both pretreatment and predischarge studies analyzable. Regional wall motion in the infarct site was measured by the centerline method and expressed in units of standard deviations (SDs) from the mean motion in 52 normal subjects. Patients treated with rt-PA (n = 77) achieved a significantly higher reperfusion rate after 90 min of treatment. Perfusion of the infarct-related artery improved from visual grade 0 or 1 (total occlusion or penetration without perfusion) to grade 2 or 3 (partial or full reperfusion) in 62% receiving rt-PA vs 31% receiving SK (n = 68) (p less than .001). However, the ejection fraction did not change significantly from before treatment to before discharge in either treatment group (+0.7 +/- 6.7% vs +1.0 +/- 8.3%, respectively). A small but significant increase in regional wall motion was observed in each of the two groups (+0.4 +/- 0.8 vs +0.3 +/- 0.8 SD/chord, respectively; each p less than .001 compared with baseline). This was countered by declines in the hyperkinesis of the noninfarct region (-0.3 +/- 1.0 SD/chord [p = .01] compared with baseline and -0.2 +/- 1.0 SD/chord [p = .23], respectively). Analysis of the combined groups revealed that the ejection fraction increased only in patients who achieved reperfusion by 90 min after onset of therapy or who had subtotal occlusions initially. There was greater recovery of left ventricular function in patients who achieved reperfusion earlier vs later than 4 hr after symptom onset and in patients with vs without some collateral circulation to the infarct-related artery.


Assuntos
Infarto do Miocárdio/tratamento farmacológico , Estreptoquinase/administração & dosagem , Ativador de Plasminogênio Tecidual/administração & dosagem , Cateterismo Cardíaco , Avaliação de Medicamentos , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/fisiopatologia , Humanos , Infusões Intravenosas , Infarto do Miocárdio/fisiopatologia , Proteínas Recombinantes/administração & dosagem , Volume Sistólico/efeitos dos fármacos , Fatores de Tempo
17.
Am J Cardiol ; 59(6): 519-22, 1987 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-3825888

RESUMO

To determine whether arteriographic dimensions of the acutely recanalized coronary lumen provide information about regional perfusion or clinical outcome, quantitative arteriography was used to measure minimum luminal diameter achieved with intracoronary streptokinase administration in 44 patients with acute myocardial infarction (AMI). Degree of coronary reperfusion was independently assessed visually using the criteria applied in the multicenter Thrombolysis in Myocardial Infarction study. Minimum diameter and qualitative reperfusion grade were both assessed from 172 coronary injections during thrombolysis. Partial perfusion (grade 1 or 2) was seen in 95 of 135 injections (70%) in which the minimum diameter was less than 0.6 mm and complete perfusion (grade 3) was seen in 35 of 37 injections (95%) in which it was 0.6 mm or more (p less than 0.001). Repeat cardiac catheterization was performed at 5.5 +/- 4.9 weeks after AMI (n = 20). When vessels were opened acutely to a minimum diameter of less than 0.6 mm, 5 of 12 vessels (42%) were reoccluded at the time of restudy and 8 of 29 patients (28%) died within 12 months. By contrast, 0 of 8 vessels (0%) were reoccluded when the artery was opened to a diameter of at least 0.6 mm (difference not significant), and only 1 of 15 patients (7%) died (p less than 0.05). Of the patients with grade 1 o r 2 perfusion at the end of the thrombolytic infusion, 7 of 19 (37%) died within 12 months and 2 of 4 vessels (50%) reoccluded; of the patients with grade 3 perfusion, 2 of 25 (8%) died (p less than 0.05) and 2 of 16 vessels (13%) reoccluded (difference not significant).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Infarto do Miocárdio/tratamento farmacológico , Estreptoquinase/uso terapêutico , Adulto , Idoso , Angiografia Coronária , Circulação Coronária , Vasos Coronários/anatomia & histologia , Humanos , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/fisiopatologia , Prognóstico , Estreptoquinase/administração & dosagem
18.
J Am Coll Cardiol ; 8(6): 1318-24, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3491099

RESUMO

Medical certification to return to work after coronary bypass surgery in occupations that carry a risk to public safety is controversial, particularly for airline pilots. To address this issue, 10,312 patients from the CASS registry who underwent coronary bypass surgery were studied and 2,326 men with clinical and postoperative characteristics similar to those of the average airline pilot who might apply to renew his license after surgery were selected. The 5 year probability of remaining free of an acute cardiac event, defined as acute coronary insufficiency, myocardial infarction or sudden death, was 0.92 +/- 0.01 (mean +/- SE) for the 1,207 men without previous myocardial infarction and 0.98 +/- 0.01 for the 122 men who never smoked and did not have a history of hypertension. Among the 1,119 men with a previous myocardial infarction, the probability of remaining free of acute cardiac events was 0.91 +/- 0.02 and 0.92 +/- 0.02 when left ventricular contraction score was 5 to 9 and 10 or greater, respectively. In this patient subgroup, mortality rate was similar to that of the age-matched U.S. male population when the left ventricular contraction score was 5 to 9 (4.0% versus 4.3%; p = NS) but significantly worse when the left ventricular contraction score was 10 or greater (7% versus 4.2%; p = 0.05). The data from this CASS registry study are pertinent to the question of operationally unlimited first-class medical certification of carefully selected airline pilots after coronary bypass surgery.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Medicina Aeroespacial , Ponte de Artéria Coronária/reabilitação , Adulto , Certificação , Cardiopatias/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Análise de Regressão , Risco
19.
Circulation ; 74(4): 796-804, 1986 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3757191

RESUMO

The value of performing biplane vs single plane analysis of regional wall motion from contrast ventriculograms was determined in 102 patients who received thrombolytic therapy and who underwent biplane ventriculography during acute myocardial infarction (n = 67), at follow-up more than 2 weeks later (n = 80), or both (n = 45). Hypokinesis in the infarct region and hyperkinesis in the noninfarct region were measured by the centerline method in the respective artery territories, which were defined from the data of 62 patients with single-vessel disease and were expressed in units of standard deviations from the mean of 32 normal subjects. Hypokinesis was more severe and extended over a longer segment of the left ventricular contour when measured in the right anterior oblique (RAO) projection in thrombosis of the left anterior descending coronary artery (LAD) but more severe and extensive in the left anterior oblique (LAO) projection in circumflex stenosis. Hyperkinesis opposite the LAD or the circumflex was greater in the LAO projection. In patients with thrombosis of the right coronary artery, wall motion abnormalities were similar in the two projections. Thus the evaluation of hypokinesis caused by acute coronary thrombosis and of the effect of therapeutic interventions in salvaging function can be adequately evaluated from single-plane 30 degree RAO ventriculograms, except in the small minority of patients with circumflex thrombosis.


Assuntos
Ventrículos do Coração/diagnóstico por imagem , Infarto do Miocárdio/diagnóstico por imagem , Cinerradiografia/métodos , Meios de Contraste , Ventrículos do Coração/fisiopatologia , Humanos , Movimento , Infarto do Miocárdio/fisiopatologia
20.
Circulation ; 74(2): 293-305, 1986 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3731420

RESUMO

We sought to identify theoretical advantages and applications of the centerline method for quantitative assessment of regional ventricular function. Motion was measured along 100 chords constructed perpendicular to a centerline drawn midway between the end-diastolic and end-systolic contours, and normalized for heart size. Abnormality was expressed in units of standard deviations from the mean motion in a normal reference population to indicate both the severity and significance of the wall motion abnormality. The mean abnormality averaged over 100 chords correlated highly with the area ejection fraction (r = .97). The centerline method uses a "sliding window" to measure motion where it is abnormal, because assessment of wall motion in predefined regions of the ventricular contour underestimates abnormality. From the 100 data points, the extent (% of contour) of regional abnormalities can also be determined. The severity of hypokinesis at the site of acute myocardial infarction correlated better with infarct size estimated from creatine kinase release (r = -.78) than did the ejection fraction or the circumferential extent of hypokinesis. Because the centerline method measures motion along locally determined vectors, and requires no apex, origin, coordinate system, or geometric reference figure, it can be applied to contours as dissimilar as the 60 degree left anterior oblique projection of the left ventricle and the 75 degree left anterior oblique projection of the right ventricle.


Assuntos
Doença das Coronárias/diagnóstico , Testes de Função Cardíaca , Função Ventricular , Computadores , Circulação Coronária , Creatina Quinase/metabolismo , Humanos , Movimento , Contração Miocárdica , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/fisiopatologia
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