Ask The Doctors: April 2015
Q. My cardiologist likes the relatively new drug rivaroxaban (Xarelto ®) as an alternative to warfarin. I have atrial fibrillation and have done well on warfarin, though the dosage does have to be adjusted periodically. Is a switch to rivaroxaban worth it?
A. For many years, warfarin (Coumadin ®) was the only available anticoagulant pill for patients with atrial fibrillation (AF). For individuals with mechanical heart valves, or those with AF related to rheumatic fever, it is still the only choice. Your question addresses a common concern, especially since warfarin has been joined by several drugs known as new oral anticoagulants, or NOACs in recent years. Rivaroxaban (Xarelto ®), has been prescribed in the U.S. since 2011, and is approved by the FDA for treatment of nonvalvular AF. It is also approved for the prevention of deep vein thrombosis in patients undergoing certain orthopedic procedures. Other NOACs include dabigatran (Pradaxa ®), apixaban (Eliquis ®), and edoxaban (Savaysa ®).
The main concern for patients with AF is that they are roughly five times more likely to have a stroke than those without the arrhythmia. Warfarin has been shown unequivocally to reduce this risk by about 60 percent, and the NOACs have been found to work at least as well as warfarin in stroke prevention. Patients treated with rivaroxaban, compared to those treated with warfarin, were less likely to experience fatal bleeding or intracranial bleeding. However, a major shortcoming of NOACs is that, unlike warfarin, no effective antidote exists. This is important because, if an individual on warfarin experiences bleeding, fresh-frozen plasma or prothrombin concentrates can be used to immediately reverse its blood-thinning qualities. In contrast, the effects of NOACs are not immediately reversed by such plasma products, making it more difficult to stop the bleeding. While efforts are underway to create specific antidotes for NOACs, they are still in the experimental phases. So yes, rivaroxaban is an effective and convenient medication for people with AF, but challenges involved in reversing its effects may temper your enthusiasm.
Q . I need to lose weight and make serious changes in my diet. I often read in Heart Advisor that a dietitian can help you develop a more heart-healthy eating style. But how does one work with a dietitian?
A. A dietitian can be a key member of your treatment team. While physicians give broad recommendations regarding dietary changes and weight loss, dietitians can take those guidelines and distill them down into specific, practical instructions. Dietitians are trained professionals with undergraduate degrees of either Registered Dietitian (RD) or Registered Dietitian Nutritionist (RDN), and about 50 percent of dietitians have earned a graduate degree, as well. All of this education, combined with a healthy dose of “people skills,” help dietitians address two of the most difficult challenges we face: changing what we eat, and losing weight. Dietitians review the doctor’s instructions, then learn everything they can about your medical condition by reading the medical record and interviewing you. They determine your current dietary intake and what needs to be changed in order to lose weight but still maintain a healthy diet.
Dietitians may also work in conjunction with exercise physiologists to decide on your appropriate caloric expenditure—in other words, an exercise program. The beauty of the dietitian’s plan is that, in contrast to your average diet, it is specifically tailored to your medical condition and needs, and it comes with motivation and support included. Finally, Medicare Part B covers dietitian services, if you are referred by a physician. However, the number of visits covered per year is limited. Talk to your dietitian about this, so you can make the most efficient use of your time spent together.