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Percutaneous coronary intervention (PCI) can safely be performed in patients with end-stage liver disease and coronary artery disease (CAD), according to a small study published in the July 2011 issue of Liver Transplantation. Questions remain, however, regarding how to best manage these patients.

According to the paper, “percutaneous revascularization has traditionally not been an option [for this population] given the thrombocytopenia and coagulopathy common in patients with end-stage liver disease.”

Investigators led by Babak Azarbal, MD, of Cedars-Sinai Medical Center (Los Angeles, CA), retrospectively analyzed the outcomes of 16 patients with end-stage liver disease who underwent PCI for hemodynamically significant CAD. All patients were considered otherwise good candidates for liver transplantation.

Fifteen of the 16 patients underwent PCI with BMS, while the remaining patient received balloon angioplasty alone. Median platelet count was 68 x 10⁹/L, with 44% exhibiting severe thrombocytopenia (≤ 50 x 10⁹/L). Median diameter stenosis per lesion was 80%, international normalized ratio was 1.3, and Model for End-stage Liver Disease score was 13.0. The femoral approach was used in all patients.

PCI was successful in all but 1 patient, who had residual stenosis after stenting. There were no deaths or MIs during 1-month follow-up, nor did any subjects develop hematoma. By the end of the study period, 9 patients had been added to the waiting list for liver transplantation, and 3 had received a transplant.

All patients were maintained on dual antiplatelet therapy for 1 month following PCI, as per guideline recommendations. Patients did not routinely receive platelet transfusions, packed red blood cell transfusions, fresh frozen plasma, or cryoprecipitate prior to PCI. One patient received a single unit of packed red blood cells, and another was transfused a unit of platelets, based on clinical need.

Outcomes a Pleasant Surprise

“The prevalence of CAD was previously thought to be lower in patients with [end-stage liver disease] than in the general population,” though this has been countered by multiple studies, Dr. Azarbal told TCTMD in a telephone interview. CAD prevalence is estimated to be 20% to 28% in this population, he reported, with the highest numbers seen in patients over the age of 50 years.

“This was a small study, and we preselected the patients so they were not the highest risk, but most had thrombocytopenia,” Dr. Azarbal noted. “Surprisingly, we found it was feasible and safe to do PCI in these patients and that the bleeding risk was quite low and acceptable, and we were able to get most of them through to clearance for liver transplantation.”

But Ajay J. Kirtane, MD, SM, of Columbia University Medical Center (New York, NY), had several questions about the study.

In an e-mail correspondence with TCTMD, Dr. Kirtane asked, “What anticoagulation regimen was used? And if it was heparin, what was the target [activated clotting time]? Were the doses of clopidogrel or aspirin altered (lowered)? Could the use of the radial approach (particularly for patients with severe thrombocytopenia) have rendered the procedure safer?”

Best Management Debated

In a telephone interview with TCTMD, Jeffrey A. Breall, MD, of Indiana University (Indianapolis, IN), noted that, “The study says [PCI is] a technical thing that can be done but the question is should it be done?”

Specifically, Dr. Breall questioned how much CAD is enough to warrant intervening in these patients. “Many transplant surgeons in the United States . . . want all of these patients to undergo angiograms preoperatively, whether or not they have symptoms or a positive stress test. And if they see anything like a moderate lesion, they want us to fix it,” he noted. “Is that the right thing to do? We don’t know. We don’t know what the outcomes are for these patients longer than a month. . . . How many of these patients will have a significant bleeding episode on dual antiplatelet therapies at the interventional site or an alternate site downstream?”

Dr. Kirtane agreed. “Given the shortage of organs in the United States, transplant physicians/teams are reluctant to allow transplantation in an individual with significant cardiac abnormalities, lest the patient suffer a bad outcome and the organ is lost,” he said. “Thus, the threshold for revascularization may be lower than for patients not undergoing transplantation.”

In addition, “In many studies that have been done so far where you compare the normal population with patients with coronary disease pre-noncardiac surgery and you randomize them to revascularization or medical therapy, there’s no difference [in outcomes],” Dr. Breall said. “Either there’s something unique about liver surgery or we’re putting too many stents into these patients.”

“No definitive clinical pathway exists for patients with [end-stage liver disease] and coexistent CAD,” Dr. Azarbal responded. “Liver transplant surgery is one of the highest risk surgeries, if not the highest risk surgery from a cardiac perspective. These people are malnourished, they’re coagulopathic, their bleeding risk is insane. It’s not uncommon for the patient to require 50 to 60 units of blood transfusions. So, if they have clinically significant coronary disease, they typically get denied liver transplantation, and when they get denied, they are going to perish. They don’t have any other options.”

In short, this study “is the first step in answering the more important and clinically relevant question of whether PCI improves clinical outcomes in patients with [end-stage liver disease] undergoing liver transplantation,” he said.