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OBJECTIVES To evaluate the relationship between platelet reactivity and atherosclerotic burden in patients undergoing percutaneous coronary intervention (PCI) with pre-intervention volumetric intravascular ultrasound (IVUS) imaging. BACKGROUND Atherosclerosis progresses by the pathologic sequence of sub-clinical plaque rupture, thrombosis and healing. In this setting, increased platelet reactivity may lead to more extensive arterial thrombosis at the time of plaque rupture, leading to a more rapid progression of the disease. Alternatively, abnormal vessel wall biology with advanced atherosclerosis is known to enhance platelet reactivity. Therefore, it is possible that by either mechanism, increased platelet reactivity may be associated with greater atherosclerotic burden. METHODS We analyzed patients who underwent PCI with pre-intervention IVUS imaging and platelet reactivity functional assay (P2Y12 reaction-units [PRU]) performed >16 hours post-PCI after stabilization of clopidogrel therapy (administered pre-PCI). A PRU value of >230 defined high on-treatment platelet reactivity (HPR). RESULTS Among 335 patients (mean age 65.0; 71% male), there were 109 patients with HPR (32.5%) and 226 without HPR (67.5%), with HPR being associated with diabetes and chronic renal insufficiency. By IVUS analysis, HPR patients had significantly greater target lesion calcium length, calcium arc, and calcium index. Furthermore, HPR patients tended to have longer lesions and greater volumetric dimensions, indicating higher plaque volume, larger total vessel volume and also greater lumen volume, despite similar plaque burden. By multivariable analysis controlling for baseline clinical variables, HPR was the single consistent predictor of all IVUS parameters examined, including plaque volume, calcium length and calcium arc. CONCLUSIONS Increased platelet reactivity on clopidogrel treatment, as defined by a PRU value of >230, is associated with greater coronary artery atherosclerotic disease burden and plaque calcification.

Using three-dimensional IVUS to assess vascular calcification, these data confirm an independent, inverse relationship between body size and index lesion CAC in patients with obstructive coronary artery disease.

Renal insufficiency (RI) is a prognostic marker in patients with cardiovascular disease. In this study, the latest standard of glomerular filtration rate (GFR) calculation, that is the modification of diet in renal disease (MDRD) study equation, is used to measure the difference in the outcome of coronary artery bypass graft (CABG) surgery in various GFR groups. Between 2000 and 2005, 1,055 patients underwent CABG surgery and were categorized into 5 groups according to the National Kidney Foundation guidelines: stage 1 = normal renal function; stage 2 = mild RI; stage 3 = moderate RI; stage 4 = severe RI; stage 5 = end-stage renal failure (excluded). Precautions were taken in RI patients to avoid perioperative hypotension, fluid overload and limited cardioplegia; cardiopulmonary bypass time was kept at a minimum by performing an essential number of grafts only. Thirty-day mortality occurred in 5 of 1,052 patients (0.48%) with no statistical difference in stages 1–4. There was increase in bleed requiring reoperation and total complications from stages 1 to 4, but it was not statistically significant. Preoperative renal dysfunction in CABG surgery patients is an important predictor of outcome. Patients undergoing CABG surgery can have acceptable results without significant increase in complications and mortality provided that risk factors are minimized perioperatively.