segunda-feira, março 22, 2010
Imagem como substituta de eventos clínicos
Seeking Alternatives to Hard End Points
Is Imaging the Best APPROACH?
Atheroma burden is a strong predictor of future events, especially in diabetic individuals,6 and, not surprisingly, imaging the morphology of the vessel wall with IVUS has been a fruitful area of research. From using IVUS to understand the morphology in atherosclerosis in diabetic individuals, it has been used in the current study as a possible surrogate for future events and a predictor of efficacy of therapy. Although used in multiple studies, this approach raises important questions for investigative strategies. Is the change in plaque volume a good surrogate for future events (the main parameter that the physician and the patient are concerned with), or should we image more than just plaque volume to understand this risk? It is important to recognize that the surrogate primary end points, such as PAV, offer potential in terms of evaluating the progression or regression of atherosclerotic process, and allow for rather smaller clinical trials in comparison with those powered for clinical events. However, convincing evidence that links PAV to change in cardiovascular risk is still lacking, and this makes IVUS-based trials, even if the results are strongly positive, still not entirely conclusive. One could argue that nearly 10 years’ worth of multiple IVUS-based studies have provided important incremental information that, however, has not yet been translated into a robust clinical event or outcome-related correlation. It might thus be time to move on to explore techniques that go beyond IVUS-verified PAV and to establish the relationship between IVUS characteristics and outcomes.
Editorial discute o estudo "Efeito da rosiglitazona na progressão da aterosclerose coronária em pacientes com Diabetes Mellitus Tipo 2 e Doença Arterial Coronariana"
Não houve regressão ou diminuição da progressão significativa da Aterosclerose ao Ultrassom coronário com o uso de uma glitazona.
Sempre que uma droga falha em reduzir a Aterosclerose, questionam se o exame é eficiente para isso.
Deveriam questionar se a droga é realmente boa para esse destino.
Clinicamente, as glitazonas estão na zona "zinza" do benefício para coronariopatia.
Isso não é culpa do ultrassom.
Quando o caçador é míope, põe a culpa no cão!