Cancer Patients Face Increased Risk of Acute MI, More PCI Complications, Higher Mortality, and Soaring Costs

WASHINGTON, DC—The incidence of acute MI in patients already living with cancer has climbed significantly in recent years, according to new numbers presented yesterday at TCT. What’s more, cancer patients undergoing PCI for acute MI face a greater risk of complications, as well as longer and costlier hospital stays, than those without the disease.

"I think what we're seeing in contemporary care is, we're seeing more complex patients showing up in the cath lab. That's why the trends we are showing over 10 years are so robust,” researcher Mladen I. Vidovich, MD (University of Illinois Hospital & Health Sciences System, Chicago, IL), said to TCTMD. “Is it possible that there is an effect of cancer therapies on the coronaries? It is very likely.”

Vidovich and his fellow investigator, Konstantinos V. Voudris, MD (Advocate Christ Medical Center, Chicago, IL), who presented the findings in moderated poster session, used data from the HCUP Nationwide Inpatient Sample between 2002-2013 across the United States to assess the influence of cancer on acute MI outcomes. Most of the cohort (92.9%) of more than 3 million patients had not been diagnosed with cancer.

Acute MI patients with a history of cancer treated with PCI had a higher rate of all-cause mortality (3.9% vs 3.0%), longer hospital stays (4.3 vs 4.7 days), and higher hospital costs ($70,492 vs $75,135) than those who did not have the disease. Cancer patients were also more likely to develop acute kidney injury (9.0% vs 7.1%) and require blood transfusion (6.7% vs 3.7%, P < 0.0001 for all comparisons).

All of the differences persisted—and in many cases were more striking—in a propensity-matched analysis. Costs, for example, averaged $75,135 in patients with malignancies to $53,484 in patients with no cancer diagnosis (P < 0.0001).

"Studies like this, they help you because . . . we have a bunch of cardiology risk calculators [but] we don't throw in cancer in our models,” Vidovich said. “Whether it needs to be there or not, I think we need to do more work [to know], but clearly it is possibly one of the risk factors for complications, bleeding, [and] maybe death."

According to the researchers, cancer remains the second leading cause of death in the United States, after heart disease, yet cancer incidence is relatively stable in the adult population. The incidence of acute MI in cancer patients, however, appears to be climbing.

Certain cancer therapies are hypothesized to cause acute coronary syndromes by injuring the vascular system, causing damage directly to the myocardial or pericardial tissue, or by fostering a hypercoagulable state, Voudris explained in his presentation. In addition, certain chemotherapy drugs, such as flourouracil, vinblastine, and cisplatin, are also associated with myocardial ischemia.

Rise in PCI for Acute MI Among Cancer Patients

In a second analysis, the researchers looked at nearly 50 million people with a history of cancer. Among them, 246,081 (0.49%) underwent PCI for acute MI. Patients with skin cancer had the highest rates of PCI at 1.07%, after a relative 32.6% rise during the 12-year period. Patients with gynecologic cancer saw a 78.8% rise in PCI for acute MI (from 0.22% to 0.39%), and those with pulmonary cancer saw a 75.6% rise (from 0.26% to 0.46%). Over the 12 years, patients with genitourinary cancer, gastrointestinal cancer, hematologic cancer, and breast cancer all saw increases.

Growing interest in the field of cardio-oncology is raising awareness of some of these issues, with different professional societies issuing statements or offering fellowships that stress the importance of cross talk between specialties, particularly as the population ages and as advances in both cancer and cardiac care have improved survival of patients battling these conditions.

“What we are trying to do is [show] there is actually a trend occurring right now in the US,” Voudris said. “Most importantly,” he added, “we want to raise awareness for so people will look into it more and there will be new studies that actually will be designed to look into that specific topic."