Acute coronary syndromes: an emphasis shift from treatment to prevention; and the enduring challenge of vulnerable plaque detection in the cardiac catheterization laboratory

Rupture of vulnerable plaques is the main cause of acute coronary syndromes and myocardial infarctions. Identification of these vulnerable plaques is therefore essential to enable the development of treatment modalities to stabilize them. Several intravascular technologies, investigating coronary areas that will be responsible for future events, are highlighted in this review. The ideal technique would provide morphological, mechanical and biochemical information. Although several imaging techniques are currently under development, none of them alone provides such an all-embracing assessment. Optical coherence tomography has the advantage of high resolution, thermography has the potential to measure metabolism, and Raman spectroscopy obtains information on chemical components. Intravascular coronary ultrasound (IVUS) and IVUS-palpography are easy to perform and assess morphology and mechanical instability. Shear stress is an important mechanical parameter deeply influencing vascular biology. Nevertheless, all these techniques are still under investigation and, at present, none of them can unequivocally and comprehensively identify a vulnerable plaque and, most importantly, predict its further development. From a clinical point of view, most techniques currently assess only one feature of the vulnerable plaque. Thus, a combination of several modalities will be important in the future to ensure a high sensitivity and specificity in detecting vulnerable plaques.