Intravascular ultrasound predictors of major adverse cardiac events in patients with unstable angina

Background: Intravascular ultrasound (IVUS) predictors of native culprit le sion morphology for occurrence of major adverse cardiac events (MACE) have not been reported. More over, the published data on IVUS predictors of rt s tenosis include patients with stable and unstable angina, although the deve lopment and progression of atherosclerosis related to unstable coronary syn drome is different from that of stable angina. Hypothesis: This study investigated whether IVUS-derived qualitative and qu antitative parameters of native (preangioplastic) plaque morphologic featur es can predict major adverse cardiac events in patients with unstable angin a. Methods: Clinical (age, Sender, coronary risk factors), qualitative and qua ntitative;angiographic (lesion localization, morphology, pre- and postangio plastic minimal lumen diameter; reference diameter, and percent diameter st enosis), and IVUS variables (soft/fibrocalcific plaque, calcification, pres ence of thrombus or plaque disruption, different types of arterial remodeli ng, pre- or postangioplastic minimal lumen, external elastic membrane and p laque cross-sectional area, and plaque burden of the target lesion and refe rence segments) were analyzed by regression analyses using the Cox model, a ssuming proportional hazards. Results: Of 60 consecutively enrolled patients, 21 suffered from MACE, whil e 39 remained event-free during the followup period. Multivariate regressio n analyses revealed that the presence of adaptive remodeling [p = 0.0177, r isk ratio (RR) = 3.108, with 95% confidence interval (CI)= 1.371-8.289] and the preangioplastic lumen cross-sectional area (p = 0.0130, RR = 0.869, wi th 95% CI = 0.667-0.913) are independent predictors of MACE during follow-u p, as is postangioplastic angiographic minimal lumen diameter (p = 0.0330, RR = 0.715 with 95% CI = 0.678-0.812). Conclusions: Adaptive remodeling and preangioplastic lumen cross-sectional area determined by IVUS and postangioplastic minimal lumen diameter calcula ted by quantitative angiography are significant independent predictors of t ime-dependent MACE in patients with unstable angina.