Assessing intermediate coronary lesions: angiographic prediction of lesion severity on intravascular ultrasound.

BACKGROUND: Intravascular ultrasound (IVUS) can detect atherosclerotic compromise in coronary segments where conventional angiography cannot. However, IVUS is more invasive, expensive and laborious than angiography. We compared the detection of stenosis by IVUS and angiography and identified angiographic predictors of severe luminal stenosis on IVUS in patients with angiographically-intermediate coronary lesions. METHODS: Fifty-six patients with myocardial ischemia and intermediate stenosis by quantitative coronary angiography (QCA) underwent IVUS assessment of the culprit artery. The results from IVUS and QCA were compared using the two-tailed unpaired t-test. Multiple regression analysis was performed to identify QCA parameters that could predict the presence of severe stenosis on IVUS, defined as a minimum luminal area (MLA) < or = 4 mm2. RESULTS: A total of 63 stenotic coronary lesions were classified as intermediate by QCA; 68% of these were found to be severe on IVUS. There was a weak correlation between IVUS and QCA with respect to percentage of stenosis, minimum luminal diameter, reference segment diameter and length of atherosclerotic compromise. In contrast, there was a significant difference in the assessment of reference segment luminal diameter, which was 2.83 +/- 0.56 mm by angiography versus 3.45 +/- 0.69 mm by IVUS (p < 0.0001). The only angiographic predictor of the presence of severe coronary stenosis on IVUS was a distal reference segment diameter < or = 2.42 mm. CONCLUSIONS: In patients with angiographically-intermediate lesions, the frequency of severe stenosis detected by IVUS was high, indicating that angiography underestimated the severity of stenosis. Distal reference segment diameter was the only predictor of a small MLA and could be used to stratify these lesions into groups with higher and lower risk of severe stenosis.

Semiologia Médica - A contribuição da cardiologia baseada em evidências / Medical semiology- The evidence based cardiology contribution

O significado de medicina baseada em evidência envolve a utilização das melhores evidências científicas externas disponíveis, integradas com o conhecimento clínico pessoal, para a tomada de decisão acerca do cuidado de pacientes, individualmente. Por melhores evidências cintíficas externas entende-se oacervo de pesquisa clínica relevante relacionada a testes diagnósticos, inclusive o exame clínico, intervenções terapêuticas e fatores prognósticos...

Ausência de fatores de risco de doença coronária em indios Yanomami e influência da aculturaçäo na pressäo arterial / Absence of coronary heart disease risk factors in yanomami indians and influence of aculturation on blood pressure

Objetivo - Investigar a hipótese de que a hipertensão arterial e a doença coronária são "doenças da civilização", analisando a distribuição dos antecedentes dessas doenças em uma população indígena e observando a influência da aculturação na pressão arterial. Métodos - Foram examinados 725 índios Yanomami de ambos os sexos, habitantes de oito aldeias nos Estados de Roraima e Amazonas. Foram feitas medidas referentes a todos os clássicos fatores de risco de doença coronária e foram colhidas amostras de urina para a dosagem de eletrólitos. Resultados - Não foi encontrado nenhum dos conhecidos fatores de risco de doença coronária. Os níveis de pressão arterial foram baixos e não aumentaram com a idade. Houve influência da aculturação na pressão arterial e essa influência foi medida, pelo menos em parte, pelo aumento do peso corporal e ingestão de sódio. Conclusão - A ausência, em uma população indígena relativamente isolada, de hipertensão e de outros fatores de risco de doença coronária e o aumento de pressão arterial com a aculturação sugerem, fortemente, que essas doenças são "doenças da civilização"

Purpose - To investigate the hypothesis that hypertension and coronary heart disease are "civilization diseases", analyzing the distribution of their antecedents in an Indian population and observing the influence of acculturation on blood pressure. Methods - Seven-hundred and twentyfive Yanomami indians of both sexes, ages above 14 years, inhabitants of eight villages in Roraima and Amazon states were examined. Measures related to all classical coronary risk factors were carried out and urine samples were collected to measure electrolytes. Results - None of the known coronary risk factors were found. The blood pressure levels were low and did not increase with increasing age. There was influence of acculturation on blood pressure and it was in part mediated by increase in body weight and sodium intake. Conclusion - The absence of hypertension and other coronary risk factors and the increase of blood pressure with acculturation, among an isolated population, strongly suggest that these diseases are "civilization diseases