Interventional indications can present confusion

November 7, 2007

Therapeutic choices in interventional cardiology are often complicated by factors, such as gastrointestinal (GI) bleeding, left anterior descending coronary artery stenosis, thrombocytopenia, and uncontrollable angina.

Therapeutic choices in interventional cardiology are often complicated by factors, such as gastrointestinal (GI) bleeding, left anterior descending coronary artery stenosis, thrombocytopenia, and uncontrollable angina.

"There are often no right answers to these clinical conundrums," said David Williams, MD, director of the cardiovascular laboratory and interventional cardiology at Rhode Island Hospital, Brown University, Providence, RI. "But there are always factors to consider."

Dr Williams compared two cases during a pre-session symposium for interventional fellows and cardiologists at the American Heart Association Scientific Sessions in Orlando, Nov. 3-7, 2007. Patients were hospitalized for a non-STEMI, both had continuing chest pain despite maximum medical therapy and both had a GI bleed.

But the patients' similarities ended there.

One patient, a 59-year old male, had no prior history of heart disease but did have acute hypertension and a family history for premature cardiovascular disease. He also had a 10mm arterial lesion, a peptic ulcer, and occult fecal blood.

The second patient was 81 years old with type 2 diabetes, had been hospitalized for chronic obstructive pulmonary disease and was a current smoker. He had multiple lesions totaling 33 mm in length, a bright red GI bleed and a hemorrhoid.

Dr Williams noted several factors to consider: the etiology of the GI bleed; the safety/benefit profile of bare metal stents (BMS) and drug-eluting stents (DES); and duration and type of antiplatelet therapy.

There is no statistical difference in death due to MI between BMS and DES, Dr Williams said, but data on revascularization shows a clear advantage for DES. Rethrombosis risk is similar for both stent types.

Current antiplatelet therapy guidelines call for 12 months of dual antiplatelet therapy unless noncardiac or other invasive procedures are planned. A DES is probably not appropriate for the first patient because he has a peptic ulcer with chronic bleeding.

The second patient's acute bleed makes him a better DES candidate. So does the length of his lesions, which exceeds label indication for DES and BMS. Data on death, MI, and revascularization all suggest lower risks for off-label DES than with off-label BMS.

Thrombocytopenia presents other challenges. Derek Chew, MD, department of cardiovascular medicine, Flinders Medical Center, Adelaide, Australia, noted that thrombocytopenia is associated with significant adverse outcomes in cardiac patients.

The Organization to Assess Strategies for Ischemic Syndromes (OASIS) trial found that platelet counts below 50 bring a three-fold higher risk of MI and 50-fold higher risk for a major bleed.

"You have to remember that these people are at risk," Dr Chew said. "Doing nothing carries a 45 percent short-term risk of death. That is not a viable option."

The most appropriate treatment for thrombocytopenic patients, he said, is BMS plus short-term aspirin and clopidogrel.