For individuals with irregular heartbeats and a prescription for anticoagulation medicine, a decision must be made before surgery on whether the patient should continue their medication. Anticoagulants, which make the blood thinner, could cause dangerous bleeding during surgery. But without the medication, a patient could be at a higher risk for blood clots and even stroke.
If a patient has an irregular heartbeat due to a condition unrelated to a heart valve, understandably known as “nonvalvular atrial fibrillation,” and they also require a surgical procedure for some reason, doctors have to make a tough decision.
Nonvalvular atrial fibrillation seems to be an increasingly common condition. John U. Doherty, MD, FACC, chair of the writing committee for the American College of Cardiology says that more than 250,000 nonvalvular atrial fibrillation patients undergo surgery every year, and that is just in North America.
As opposed to valvular atrial fibrillation, which includes patients with mitral stenosis or artificial heart valves, nonvalvular atrial fibrillation patients are at a high risk of blood clots and stroke. The difference is so key to the characteristics of each condition that a 2015 study focused solely on defining the two types of atrial fibrillation declared that “[scientists] should no longer consider the classification of [atrial fibrillation] as "valvular" (or not) for the purpose of defining the aetiology of the arrhythmia, but for the determination of a different risk of thromboembolic events and the need for a specific antithrombotic strategy.”
From the American College of Cardiology, researchers came up with a new “decision pathway document” to combat the risk of bleeding during surgery with a patient on anticoagulants and the risk of developing a blood clot for patients not on anticoagulants. For a patient in this situation, many specialists are involved in the decision-making process. And as in any case where there are many cooks in the kitchen, sometimes the best solution can be hard to determine.
"All these specialists possess valuable knowledge; however, they have differing perspectives, which can make the decision-making process complex," Doherty said. "With this new decision pathway, physicians will be able to make better-informed decisions, and this will contribute to improved patient outcomes.”
First, the new document addresses whether a patient should be taking anticoagulant medication in general, before surgery is even considered. This decision is made by assessing overall thrombotic risk of the individual patient. Then, based on the balance of risks between overall thrombotic risk and hemorrhage during surgery, doctors can decide if a patient should or should not continue anticoagulant medication during the surgical process.
The document also discusses how and when a patient should be taken off of anticoagulant medications based on what specific drug they have been prescribed (vitamin K antagonists, direct-acting oral anticoagulants). There are also guidelines for “bridging” a patient before, during, and after surgery, if this approach appears to be appropriate. “Bridging” entails temporarily stopping administration of oral medication and replacing it with either an injection or an IV drip.
Lastly, the document addresses how and when the patient should continue with their original anticoagulant medication after surgery. With the multitude of factors considered in the writing of this “antithrombotic strategy” and considering the hundreds of thousands of individuals with nonvalvular atrial fibrillation undergoing surgery every year, this new document will be an invaluable new guide for cardiologists.
The document was published this week in the Journal of the American College of Cardiology.