Resistance of the atherosclerotic plaque during coronary angioplasty: A multivariate analysis of clinical and angiographic variables

The atherosclerotic lesion resistance to balloon inflation was assessed prospectively in 200 patients undergoing primary single-site balloon percutaneous transluminal coronary angioplasty (PTCA) by using an identical inflation protocol. This resistance was evaluated by the stenosis resolution pressure, which is the pressure at which the lesion mark is no longer visible on the inflated balloon. The stenosis resolution pressure distribution was normal with a mean value of 4.4 +/- 2.3 atmospheres. Multivariate analysis revealed 4 factors related to the stenosis resolution pressure: stable angina pectoris (p < 10(-6)), the presence of calcifications (p = 0.016), the occurrence of vessel wall dissection after balloon angioplasty (p = 0.005), and the absence of a branch arising in the middle of the stenosis (p = 0.047). It is concluded that the mechanical resistance of the coronary lesion is related to the anginal status, the presence of calcifications, and the occurrence of vessel wall dissection after balloon angioplasty, probably on the basis of the plaque composition.