WASHINGTON—The issue of noncompliance of a prescribed antiplatelet therapy is fast becoming a serious problem in the management of patients after PCI procedures, according to research presented Monday at the 20th annual Transcatheter Cardiovascular Therapeutics (TCT) scientific symposium.
Dominick J. Angiolillo, MD, director of cardiovascular research and an interventional cardiologist at the University of Florida in Jacksonville, Fla., reviewed the dangers in discontinuing antiplatelet therapy for post-PCI patients, as well as suggested potential methods for better patient compliance.
To prove the dangers in discontinuing dual-antiplatelet therapy, he noted a study that appeared in JAMA this year, which found that premature discontinuation of antiplatelet therapy as a predictor of stent thrombosis.
Angiolillo also referenced the BASKET LATE Trial, presented at the American College of Cardiology meeting in 2006, which found that in the year following clopidogrel discontinuation, the primary composite endpoint of cardiac death or MI experienced a significant increase. At the time, clopidogrel was recommended for one to six months following PCI, but has since that time, has been extended for out to a year.
He warned that the ACC/AHA class one recommendations of a one-year follow-up of dual-antiplatelet therapy is necessary, not only for drug-eluting stents (DES), but also for bare-metal stents (BMS).
Another study, that appeared in JAMA in February, conducted by P. Michael Ho et al, found a rebound in the clinical adverse events, once there is withdrawal of clopidogrel. Specifically, the authors showed “a clustering of adverse events in the initial 90 days after stopping clopidogrel among both medically treated and PCI-treated patients with acute coronary syndrome, supporting the possibility of a clopidogrel rebound effect.”
Based on these and other studies, Angiolillo surmised that when patients discontinue their dual-antiplatelet therapy, experience a marked increase in platelet activity.
In trying to identify the root cause what causes patients with acute coronary syndrome (ACS) to discontinue their clopidogrel or dual-antiplatelet therapy usage, he noted that there is sometimes a lack of communication between the cardiologist and the patient, due to the nature of the disease. Also, Angiolillo suggested that the patients may be hearing conflicting recommendations from their primary-care physician, with whom the patient may have a more long-standing relationship.
He noted that the PREMIER Registry, which appeared in Circulation in 2006, found that among 500 MI patients treated with DES, the following characteristics had the most effect on non compliance: older age; costs; poor education; single; and poor counseling. The registry also found mortality lower in patients who followed the recommended dual-antiplatelet therapy: 0.7 vs. 7.5 percent.
“Poor education and poor counseling often go hand-in-hand,” Angiolillo noted.
He concluded that noncompliance to dual-antiplatelet therapy has important prognostic implications for PCI/ACS patients. He added that “in-hospital adherence to guidelines improves outcomes and increases the likelihood of long-term guideline adherences.”
Angiolillo also stressed the importance of getting “to know one’s patients before sending them to the cath lab, if possible.” He explained that forming a relationship with one’s patients and counseling them on the importance of compliance with the antiplatelet medication at discharge; will “highlight the dramatic consequences associated with withdrawal.”