Acute complications and restenosis in the first few months after a successful procedure remain the two major limitations of coronary balloon angioplasty. New devices have been developed in order to avoid these limitations. We tested the directional atherectomy catheter clinically and compared the immediate quantitatively analysed results with two other recently developed devices and conventional balloon angioplasty. A gain in luminal diameter of 1.7 mm after atherectomy was observed in 7 patients. This is far more than could be accomplished by balloon angioplasty, stenting and rotablation. Furthermore, the size of the device in relation to the size of the obstructed vessel suggests that a Dotter effect is partly responsible for the gain in luminal diameter. Whether this large gain can prevent restenosis remains to be confirmed. Preliminary literature data suggest that this is not the case.
No abstract is provided for this article.
β-Adrenoceptors regulate many aspects of lung function and β-adrenergic agonists have become the most widely used bronchodilators for the treatment of obstructive airway diseases. There have been important advances in our understanding of the molecular structure and regulation of β-adrenoceptors, which have implications for elucidating β-adrenoceptor function in airway disease and the mechanisms of action of β-agonists [1, 2]. At least three β-adrenoceptors are now recognized (Table 1). β1-Receptors, which are preferentially activated by noradrenaline, are physiologically regulated by sympathetic nerves; β2-receptors are preferentially regulated by circulating adrenaline; β3-receptors or "atypical" β-receptors are involved in lipolysis but are increasingly recognized in other functions. β2-Receptors predominate in lungs and mediate most of the effects of β-agonist on airway function.
Recent reports of randomised trials (ABSORB II, ABSORB Japan and ABSORB China) have raised questions on the “non” non-inferiority of the acute and long-term performance of the Absorb bioresorbable scaffold (BRS) when compared to the XIENCE stent (both Abbott Vascular, Santa Clara, CA, USA). Furthermore, very late scaffold thrombosis has been perceived as a possible new unexpected “enemy” – unexpected because thrombosis occurred at a moment when the scaffold was expected to have disappeared. The three main players in this new debate are: the patient/lesion, the device, and the interventionalist. The selection of the patient/lesion might be inappropriate, the device may have inherent deficiencies and the operator may have used the device inappropriately. If the matter were not of paramount importance for the wellbeing of our patients and were not a topic that demands our utmost medical attention, we would have rephrased the title of a past editorial, “Who was thrombogenic, the device, the doctor…or the patient?”. The format of the present commentary is neither an editorial nor a review, but should be considered as the personal views of two clinical scientists who have been involved in the pioneering investigations of this device and have historical and current insights into the field.
