CardioSource WorldNews December 2014 - Page 12

EDITOR’S CORNER Alfred A. Bove, MD Interim Editor-in-Chief, CardioSource WorldNews New Data that Change Practice I n this edition of CWSN, we hear about the annual American Heart Association scientific sessions that were held in cold Chicago in November. We usually attend a scientific meeting such as this with some expectation of interesting data that will ultimately lead to newer guidelines and improved care. It is uncommon to head back from the meeting with provocative findings that promise to quickly change the way we practice cardiology. The LDL discussion continued at this meeting. Two important papers were presented. One presented the results of IMPROVE-IT, which examined the benefit of ezetimibe when added to simvas tatin for the reduction of cardiac events after an initial myocardial infarction (MI). Average follow-up was 6 years and the study was conducted over a 10-year period. The data showed a 6.4% reduction in the combined primary endpoint (all cardiovascular events), and a 13% reduction in MI. The LDL level in the combined therapy group was 54 mg/dl. The study rekindles the argument for LDL targets since the lower LDL was associated with significantly reduced cardiovascular events and was achieved with a non-statin (ezetimibe). The second trial came from the original investigators from the West of Scotland study (WOSCOPS) who presented their 20-year followup data. Because the medical records for the government health system in Scotland are archived, they were able to obtain mortality data on nearly all of the original study patients. Over the 20 years there was a 27% risk reduction for coronary mortality and a 13% risk reduction for all cause mortality in patients randomized to pravastatin compared to placebo. Their data support the concept that lower LDL is associated with reduced cardiovascular mortality. These two studies offer compelling evidence that we should be aiming for LDL targets and, while the guidelines released in 2013 discourage using LDL targets and focus on statin therapy, here we see data supporting the LDL hypothesis. In my practice, when a patient has an indication for a statin based on the new risk calculator, they universally ask about the target LDL. To provide motivation, I still feel compelled to blurt out a number like 100 or 70 depending on the patient’s 10 CardioSource WorldNews “ he DAPT trial T challenges our thinking on duration of dual antiplatelet therapy.” cardiovascular disease status, and to aim for the target, but with less compulsion. Adding to the discussion, there were still more PCSK9 studies reported at the AHA meeting. ODESSY ALTERNATIVE reported the effects of the PCSK9 inhibitor alirocumab in statin intolerant patients. As expected there was a significant reduction in LDL with alirocumab (42%) compared to ezetimibe (15%) after 24 weeks. We still are waiting for clinical outcome data from the use of PCSK9 inhibitors, as this will, if positive, clearly indicate that lowering LDL is the key component to the cardiovascular risk reduction demonstrated in the statin trials. Another thought - provoking trial was the dual antiplatelet therapy (DAPT) trial. The duration of dual antiplatelet therapy is 1 year in some guidelines, but several recent trials have indicated that even 3 months total therapy was a safe alternative. Yet we hear the occasional anecdotal report of a patient stopping dual antiplatelet therapy 3 or 4 years after insertion of a drug eluting stent (DES) and experiencing an acute coronary syndrome from stent thrombosis. At the AHA meeting, data from DAPT were presented comparing 1 year to 30 months of therapy with dual antiplatelet therapy in nearly 10,000 patients who received either bare-metal or DES for coronary disease. The patients entered the study if they were event free 1-year post stenting and were compliant with their dual antiplatelet medications. The patients were randomized to either DAPT or placebo for 18 months. Major adverse cardiac or cerebrovascular events (MACCE) were significantly lower in the 30-month versus 12-month treatment group albeit with more moderate and severe bleeding in the 30-month treatment group. In the first 12 months post stent placement, the patients with a BMS taking DAPT experienced more stent thrombosis than patients with a DES. The DAPT trial challenges our thinking on duration of dual antiplatelet therapy. It appears that 30 months provides a benefit in terms of cardiac MACCE at the expense of more bleeding. Interestingly, the reduction in MACCE was divided between MI and stent thrombosis. Not all of the events were caused by stent thrombosis. This suggests that DAPT is not only reducing risk for stent thrombosis, but also reducing risk for an MI caused by other coronary lesions. These trials involving therapy for hypercholesterolemia and for preventing stent thrombosis post-PCI challenge current guidelines and are likely to result in changes in guidelines in the future. If your patients ask for an LDL target, provide them with a number while we await more trial information to support targets. If your patient asks when to stop their dual antiplatelet therapy, suggesting 30 months or longer may not be unreasonable until we have further data. ■ Alfred A. Bove, MD, PhD, is professor emeritus of medicine at Temple University School of Medicine in Philadelphia, and former president of the ACC. December 2014