Study results presented at ACC.13 show that patients with unprotected left main coronary artery disease treated with double kissing crush stenting experienced fewer cases of restenosis and other major adverse events compared to patients who received culotte stenting.
Late-breaking results from the DK CRUSH-III trial presented at ACC.13, the 62nd Annual Scientific Session & Expo of the American College of Cardiology, indicate that the double-kissing (DK) crush technique may produce better outcomes and fewer adverse events in patients with a specific type of coronary lesion compared to treatment with culotte stenting.
Unprotected left main coronary artery (ULMCA) distal bifurcation lesions are technically demanding, often requiring double-stenting, and resulting in poorer long-term outcomes. Previous studies have looked at the effectiveness of culotte stenting and DK crush stenting with lesions, but their durability and safety were never randomly compared. The multicenter DK CRUSH-III trial evaluated DK crush and culotte stenting in patients with coronary artery disease, comparing major adverse cardiac events (MACE) at one year follow up.
From March 2009 through October 2011, 863 patients with ULMCA distal bifurcation lesions were screened in 18 centers within four countries. Later, 326 patients were clinically excluded, 117 were angiographically excluded, and one refused percutaneous coronary intervention (PCI) post-randomization. Thereafter, 419 patients were randomized, 210 to DK crush and 209 to culotte stenting.
To be included in the study, patients had to be over 18 years old, have silent ischemia, stable or unstable angina, NSTEMI, and/or STEMI over 24 hours from onset of chest pain to admission. Exclusion criteria included pregnancy, life expectancy of less than a year, specific drug allergies, severe calcification needing rotational arterectomy, and restenosis lesion.
Patients tended to be male (nearly 80%), around 65 years old, with hypertension, hyperlipidemia, diabetes, current smokers, a BMI of around 25, greater than two weeks of acute myocardial infarction (MI), previous MI, and/or previous PCI.
Primary endpoint at one year was MACE (cardiac death, MI, target vessel revascularization); secondary endpoint was in-stent restenosis (ISR) at eight months. The safety endpoint was in-stent thrombosis at one year.
At twelve months, clinical follow-up showed DK crush with a composite MACE of 13 (6.2%) versus culotte stent at 34 (16.3%), P=0.001. This included cardiac death, MI, target lesion revascularization (TLR), and target vessel revascularization (TVR). Stent thrombosis showed at 1 (.5%) and 2 (1%) for DK crush and culotte stent, respectively (P=.623). The TLR-free survival rates at one year were 97.6% and 93.3%, respectively (P=0.034). TVR-free rates were 95.7% and 89.0%, respectively (P=0.016). MACE-free survival rates at a year were 93.8% and 83.7%, respectively (P=0.001).
Key findings associated culotte stents with significantly increased one-year MACE rates in patients with ULMCA bifurcation lesions, mainly due to the increment of TVR rate. Restenotic lesions were most localized in the SB; DK crush was associated with slightly less ISR. DK crush demonstrated effectiveness in patients at intermediate or high risk and distal bifurcation angle of greater than 70. These procedure results were achieved with high volume operators; it’s unclear whether lower-volume operators could achieve the same results.
Investigators said the difference in outcomes is not in the two stents, but in how the stents are deployedâ€‘â€‘they start separately and bifurcation merges them into one. When deploying the DK crush, first one stent is placed, then the second. How to do that best, quickest, and safest without risk “has become in the US the last frontier of interventionalists,” said Gary Mintz, MD, chief medical officer of the Cardiovascular Research Foundation.