RESUMEN
Coronary arteriographic results are reported in 1535 black patients: 751 men (mean age 57 +/- 11) and 784 women (mean age 59 +/- 11). Among the black men 19%, 15%, 21%, and 4% had single-, double-, and triple-vessel and left main disease, respectively. Among the black women there were 12%, 10%, 15%, and 3% with similar involvement. Logistic regression models showed that most of the recognized risk factors were positively correlated with significant (at least one artery with > or = 50% stenosis) coronary disease, but a history of hypertension was not a significant independent predictor in either sex. ECG evidence of previous infarction increased the odds of detecting significant coronary disease by the greatest amount when controlling for other significant risk markers in women. In men both previous infarction and atypical pain (negative) were equally important. This study confirms but does not explain previous reports that have revealed less than expected angiographic evidence of significant coronary artery disease in black compared with white persons.
Asunto(s)
Población Negra , Angiografía Coronaria , Enfermedad Coronaria/diagnóstico por imagen , Análisis de Varianza , Enfermedad Coronaria/epidemiología , Femenino , Humanos , Hipertensión/complicaciones , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Factores SexualesRESUMEN
Although vasomotor activity in small pulmonary vessels has been studied extensively in the past, using the concept of resistance to flow, information on the distensibility of these vessels is very sparse. In an attempt to reduce this deficit, we adapted a theoretical method developed for small systemic vessels, to estimate distensibility of pulmonary resistance vessels in experimental animals and man. Pressure-flow data from 11 dogs and 10 human subjects (5 control subjects and 5 patients with long-standing left heart failure) were used to calculate distensibility of small pulmonary vessels. The conductance, G, was calculated from these data as the ratio of blood flow to driving pressure. The slope of the relationship between the logarithm of G1/4 and the average distending pressure (ADP) provides a graphic picture of circumferential extensibility, E, defined as percent change in radius for an infinitesimal change in ADP. Results indicate that: (1) the value of E in dogs was 1.85 +/- .40 mmHg-1 for the control state, which decreased to 1.45 +/- .43 mmHg-1 during norepinephrine administration; however, the decrease in the value was not statistically significant (p = 0.53); (2) the value of E in control human subjects was 3.38 +/- .47 mmHg-1 and the value of E in patients with left heart failure was -0.64 +/- 0.39 mmHg-1; the difference was significant (P = .0001).(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Velocidad del Flujo Sanguíneo , Insuficiencia Cardíaca/fisiopatología , Modelos Cardiovasculares , Circulación Pulmonar/fisiología , Presión Esfenoidal Pulmonar , Resistencia Vascular/fisiología , Adulto , Animales , Estudios de Casos y Controles , Adaptabilidad , Modelos Animales de Enfermedad , Perros , Elasticidad , Epinefrina/farmacología , Femenino , Humanos , Infusiones Intravenosas , Análisis de los Mínimos Cuadrados , Masculino , Persona de Mediana Edad , Circulación Pulmonar/efectos de los fármacos , Reología , Estrés Mecánico , Resistencia Vascular/efectos de los fármacos , Función Ventricular IzquierdaRESUMEN
Sudden death in young competitive athletes is most commonly due to underlying cardiovascular disease. Echocardiography has the potential to identify structural cardiovascular abnormalities, such as hypertrophic cardiomyopathy (HC), that have been incriminated in such events. In this study, echocardiography (2-dimensional and M-mode) was used as a primary screening test to assess 265 Howard University collegiate athletes for cardiovascular disease; 262 (99%) were black. Most athletes (234, 88%) had no definitive echocardiographic evidence of HC or other major cardiovascular diseases, but 30 (11%) had mitral valve prolapse, and 1 other athlete had a small atrial septal defect. In addition, 4 athletes were identified as having mild systemic hypertension. Most athletes (236 of 265) showed normal left ventricular wall thickness of less than or equal to 12 mm, but an important minority (29, 11%) had maximal ventricular septal thicknesses of greater than or equal to 13 mm that could not always be distinguished (by morphology alone) from mild anatomic expressions of nonobstructive HC. Based on this experience, preparticipation athletic screening using echocardiography as the primary test does not appear to be justified on a cost-effective basis. In addition, the substantial minority of subjects with increased wall thickness made clinical interpretation of the echocardiographic findings difficult in individual athletes.