MKSAP Quiz: Preoperative evaluation
MKSAP Quiz: Preoperative evaluation
A 65-year-old woman comes for a preoperative evaluation before elective right knee arthroplasty. The patient has severe pain and disability due to osteoarthritis of the right knee. She had a myocardial infarction 4 months ago and required a percutaneous coronary intervention with placement of a paclitaxel drug-eluting stent in the left anterior descending coronary artery. The patient also has hypertension and type 2 diabetes mellitus. She currently has no chest pain or dyspnea but can only walk two blocks and climb one flight of stairs because of the osteoarthritis. Current medications are clopidogrel, metoprolol, atorvastatin, losartan, metformin, aspirin, acetaminophen and tramadol.
Vital signs are normal. Other than evidence of bony hypertrophy of the knees and a small effusion in the right knee, the remainder of the examination is unremarkable.
An electrocardiogram shows normal sinus rhythm; Q waves in leads II, III, and aVF; and left ventricular hypertrophy.
Which of the following is the best preoperative management?
A. Postpone surgery for 6 months after stent was placed
B. Postpone surgery for 12 months after stent was placed
C. Proceed with surgery; continue aspirin but temporarily stop the clopidogrel
D. Proceed with surgery; continue both aspirin and clopidogrel
E. Proceed with surgery; temporarily discontinue aspirin and clopidogrel
MKSAP Answer and Critique
The correct answer is B) Postpone surgery for 12 months after stent was placed. This item is available to online to MKSAP 15 subscribers as item 95 in General Internal Medicine.
The American College of Cardiology/American Heart Association currently recommends that patients with recently placed paclitaxel or sirolimus drug-eluting stents continue uninterrupted dual antiplatelet therapy with aspirin and clopidogrel for at least 12 months, if possible, to minimize the possibility of in-stent thrombosis. Previous recommendations were dual antiplatelet therapy for at least 3 months for patients with sirolimus stents and 6 months for those with paclitaxel stents. The patient described here, whose stent was placed 4 months ago, should postpone surgery for an additional 8 months to reduce the risk of stent thrombosis. In patients who must undergo nonelective surgery, the risk of prematurely discontinuing one or both antiplatelet agents must be balanced against the risk of perioperative bleeding if these agents are continued.
Key Point
- For patients with recently placed paclitaxel or sirolimus drug-eluting stents, dual antiplatelet therapy with aspirin and clopidogrel should be continued uninterrupted for at least 12 months, if possible, to minimize the possibility of stent thrombosis.