https://immattersacp.org/archives/2010/06/cardiology.htm

Cardiologists highlight prevention, clopidogrel

Subspecialists leading the Internal Medicine 2010 cardiology pre-course offer advice, but also accept some from general internists about preventing cardiovascular events in high-risk patients.


The subspecialists leading the Internal Medicine 2010 precourse on cardiology were there to educate internists, but they were also looking for some help from the generalists. Specifically, they asked for assistance with the mutual goal of preventing cardiovascular events in high-risk patients.

“Hospitalization is so short. There's no time to discuss many of these important issues,” said David L. Fischman, FACP, associate professor of medicine at Thomas Jefferson University in Philadelphia. “The outpatient management is so crucial.”

Stephen L Kopecky FACP
Stephen L. Kopecky, FACP

He offered a number of tips for treating patients who have been discharged from the hospital after an acute coronary event.

Tips to communicate

To start, primary care physicians should make sure they're up-to-date on whether the patient received a stent (and if so, what kind), whether he or she has residual ischemia, and the status of the patient's ejection fraction. These factors will be important in the management of medications such as beta-blockers and ACE inhibitors.

Physicians should also discuss with patients the numerous lifestyle modifications that can reduce risk of a repeat event, including smoking cessation, diet and exercise. When discussing exercise, physicians should be sure to cover the issue of patients' capacity for exertion. “Sometimes patients are afraid to ask questions. You need to review these things,” Dr. Fischman said.

With some patients, more than a conversation may be required to get an exercise program going. “It's easy to say a patient needs to exercise, but they often don't know how to do that,” said Dr. Fischman.

Those patients may be particularly good candidates for cardiac rehabilitation, he noted. Such programs can also offer the patients a chance to get more in-depth dietary advice than a primary care office has time to provide.

Some advice on encouraging smoking cessation was offered by Stephen L. Kopecky, FACP, a professor of cardiology at the Mayo Clinic in Minnesota, who spoke about chronic coronary disease during the precourse. He warns patients about the risks of tertiary smoke; recent research has found that children who even smell smoke on someone's clothing wind up with carcinogens in their system. “You should see a grandmother's eyes get big when I tell her that,” he said.

He also has a creative argument for convincing patients, especially those with coronary disease, to get their vaccines. “I tell patients you should have a flu vaccine because I don't want you to have a heart attack or stroke.” Dr. Kopecky presented data from a 2002 Circulation study that found risk of nonhemorrhagic stroke and cardiac arrest was reduced by about half in patients who got the flu vaccine, because of the association of systemic inflammation with infarction.

Statins still needed

Even if these high-risk patients follow all of this good advice, however, they will likely require a statin as well, said Dr. Fischman. “If they're not placed on a statin in the hospital, they should be.”

Dr. Kopecky also addressed the importance of statins. He noted that studies have shown that at least a quarter of patients drop some lipid-lowering drugs within a year of prescription.

“We give patients a lot of medications but they don't continue to take them. We have to be aware of that,” Dr. Kopecky said. His solution is giving fewer lipid-lowering drugs, often just a statin and fish oil, because those two medications have the best evidence of lowering mortality.

As for which statin to give, he suggested that it didn't matter much, pointing to a 2005 meta-analysis published in the Journal of the American College of Cardiology that found that benefit depended on the reduction in LDL, not the specific statin prescribed. “The bottom line is that all the statins are about the same with the same reduction in LDL,” he said.

Anticoagulation management

The cardiology experts focused a lot of attention during the precourse on another popular drug, clopidogrel. The risks and limitations of clopidogrel have been highlighted recently by both FDA warnings and new research, and the speakers discussed some of the problems that the popular drug is posing.

The risks of mixing clopidogrel with proton-pump inhibitors (PPIs) have become fairly well-known in the past year or so, and have discouraged clinicians from overusing the latter, but sometimes there's a real need to use both drugs, noted Dr. Fischman. In those cases, it may be safest to go with pantoprazole (Protonix).

Pantoprazole has less effect on liver enzyme CYP2C19, which metabolizes clopidogrel. The differences in patients' capacities to metabolize the drug became big news in March when the FDA added a boxed warning to the clopidogrel label, advising that some patients metabolize the drug poorly and that genetic testing is available to determine which patients these are.

Most insurance won't cover the test, which costs $500 and is obscure enough that even the Mayo Clinic doesn't offer it, according to Dr. Kopecky. There is one simpler test to identify some higher-risk patients—ethnicity. About 14% of people of Chinese origin metabolize the drug poorly, compared to 1% or 2% in other races.

As for what to do once you've found the patients, Dr. Kopecky wasn't too keen on one of the FDA's possible solutions, a higher-dose regimen of a 600-mg loading dose followed by 150 mg once daily. The agency noted that the dose hasn't been tested in a large trial, and Dr. Kopecky said he isn't comfortable using it.

The FDA warning also mentioned alternate antiplatelet medications, and one of those, prasugrel (Effient), does appear to have some potential advantages over clopidogrel, Dr. Fischman said. It poses less risk of interaction and has greater antiplatelet effect, but it's got a major disadvantage, too: higher incidence of bleeding.

The bleeding risk posed by clopidogrel and other drugs is likely to be a particular concern to surgeons and anyone else who plans to cut your antiplatelet-taking patients open, the experts noted. “It comes up every day: Can this patient come off their Plavix?” described Dr. Fischman.

If the patient is taking the drug because they've received a bare-metal stent and it's been at least a month, then it's OK to halt it for surgery. But if the patient got a drug-eluting stent less than a year before, internists need to take a hard line because recommendations call for continuing antiplatelet therapy for a year in order to prevent late stent thrombosis.

“We're trying to change the mentality of the surgeon, dentist and gastroenterologist,” said Dr. Fischman. “At the very least, patients should stay on their aspirin if not clopidogrel.”