PRELIMINARY EXPERIENCE WITH ADJUNCT DIRECTIONAL CORONARY ATHERECTOMY AFTER HIGH-SPEED ROTATIONAL ATHERECTOMY IN THE TREATMENT OF CALCIFIC CORONARY-ARTERY DISEASE

A high-speed rotational atherectomy was performed followed by adjunct directional atherectomy in 10 patients with symptomatic coronary artery disease and calcified target lesions and the results were evaluated using quantitative coronary arteriography and intravascular ultrasound. Target lesion calcium is common in obstructive coronary artery disease. High-speed rotational coronary atherectomy preferentially abrades noncompliant atherosclerotic plaque material, especially calcium, but often requires adjunct balloon angioplasty to achieve optimal lumen dimensions. Directional coronary atherectomy has limited efficacy in heavily calcified plaque; usually, it is a definitive primary procedure in large arteries with noncalcified target lesions. Neither of these devices alone is effective in treating calcified target lesions in large coronary arteries. Before intervention, after rotational and adjunct directional atherectomy, these measurements were obtained: quantitative coronary arteriographic measurements of minimal lumen diameter and percent diameter stenosis and intravascular ultrasound measurements of external elastic membrane, lumen, and plaque + media cross-sectional areas; percent cross-sectional narrowing; minimal lumen diameter, and target-lesion arc of calcium. With use of quantitative coronary arteriography, the preintervention minimal lumen diameter measured 0.7 +/- 0.4 mm, increased to 1.5 +/- 0.5 mm after rotational atherectomy (p = 0.0013) and to 2.5 +/- 0.3 mm after adjunct directional atherectomy (p < 0.001). The preintervention percent diameter stenosis measured 78 +/- 15%, decreased to 50 +/- 17% after rotational atherectomy (p = 0.0011), and to 17 +/- 11% (p < 0.001) after adjunct directional coronary atherectomy. The 9 patients studied by intravascular ultrasound had arcs of target lesion calcification that measured 271 +/- 92-degrees before intervention, decreased to 210 +/- 120-degrees after rotational atherectomy (p = 0.046) and to 163 +/- 122-degrees after adjunct directional atherectomy (p = 0.0015), with distinct directional atherectomy cuts into calcium. Before intervention, target lesion external elastic membrane area measured 20.4 +/- 2.3 mm2, lumen area measured 1.5 +/- 0.6 mm2, plaque + media area measured 18.9 +/- 2.3 mm2, and percent cross-sectional narrowing measured 93 +/- 3. After rotational atherectomy, target lesion external elastic membrane area measured 21.2 +/- 2.3 mm2 (p = NS), lumen area increased to 4.4 +/- 1.0 mm2 (p < 0.001), plaque + media area decreased to 16.8 +/- 2.8 MM2 (p = 0.072), and percent cross-sectional narrowing decreased to 79 +/- 7 (p = 0.0024). After adjunct directional atherectomy, target lesion external elastic membrane area measured 23.5 +/- 2.9 mm2 (p = NS), lumen area increased further to 7.7 +/- 1.2 mm2 (p < 0.001), plaque + media area decreased further to 15.8 +/- 3.0 mm2 (p = 0.063), and percent cross-sectional narrowing decreased even more, to 67 +/- 6 (p < 0.001). Rotational atherectomy appears to alter the calcified plaque to render it susceptible to the directional atherectomy device. Thus, there seems to be a synergistic relation between high-speed rotational and adjunct directional atherectomy in treating calcified coronary artery target lesions.