PCI Patients More Likely to Die from Noncardiac Causes

Download this article's Factoid (PDF & PPT for Gold Subscribers)

Over the past 2 decades a shift has occurred in the causes of death among patients who undergo percutaneous coronary intervention (PCI), according to results of a study published online February 10, 2014, ahead of print in Circulation. During this time, noncardiac causes such as cancer, lung and neurological diseases have surpassed cardiac disease across multiple subgroups of PCI patients.

Investigators led by Rajiv Gulati, MD, PhD, of the Mayo Clinic (Rochester, MN), conducted a retrospective single-center study looking at cause-specific mortality and trends in cause of death over a 22-year period in 19,077 patients discharged after undergoing PCI. The study period was divided into 3 6-year eras according to the date of PCI:

• 1991-1996 (1^st era)
• 1997-2002 (2^nd era)
• 2003-2008 (3^rd era)

Overall, 6,857 of 6,988 deaths (37% of the total cohort) were documented using multiple sources to corroborate details. While cardiac death predominated the first era, a shift began to emerge during the 2^nd era, where cardiac and noncardiac deaths were roughly equal. By the 3^rd era, noncardiac conditions were the leading cause of death in PCI patients.

At 5 years after PCI, there was a 33% decline in the cardiac death rate across the 3 eras. This was accompanied by a 57% increase in noncardiac deaths during the same time period (table 1).

Table 1. Incidence of Cardiac vs Noncardiac Death 5 Years Post PCI^a

^aP for trend <0.001 for both cardiac and noncardiac causes.

The decline in cardiac mortality was seen across all age groups, in single and multivessel disease, and across PCI indications (stable angina or ACS). Additionally, the decline in cardiac deaths was independent of changes in baseline clinical characteristics.

The decrease was driven primarily by a reduction in deaths due to MI/sudden death (P < 0.001). Concurrently, mortality from congestive heart failure (CHF) remained unchanged (P = 0.85). The increase in noncardiac mortality was primarily attributable to cancer and chronic diseases (P < 0.001).

CHF Emerges as Target for Patient Management

According to the study authors, the time periods in the study were chosen to correspond approximately with changes in primary interventional approaches including: balloon angioplasty (early provisional stenting, 1991-1996), routine bare-metal stenting (1997-2002), and routine DES placement (2003-2008).

In a telephone interview with TCTMD, Dr. Gulati said he was surprised that deaths from CHF did not decline in a similar fashion as deaths due to MI/sudden death given the emphasis in recent years on medical therapy for CHF.

“I think the message of our paper is there is a competing risk of death from… chronic things like heart failure, cancer,” he said. “Chronic diseases really came to the forefront because of fewer cardiac-related deaths. The paper does give us a benchmark, though, that CHF is an important ongoing target to try and reduce mortality in the future.”

On a positive note, the study suggests that today more clinicians are prescribing guideline-recommended postdischarge therapies including aspirin, beta-blockers, and ACE inhibitors, Dr. Gulati said.

A Changing Perspective

“While we know what we need to do to reduce cardiac death in terms of medications and revascularizations, we mustn’t forget that patients are more likely to die of noncardiac deaths, and that means we need to work closely with our colleagues in noncardiac disciplines,” he observed. “This paper is telling us that we need to look more broadly at our patients and their risks of death.”

Similarly, in an editorial accompanying the study, Philippe Gabriel Steg, MD, of Hôpital Bichat (Paris, France), says “a new front has opened up in the war against cardiovascular disease” that has nothing to do with the heart.

“It is a reminder that greater attention should be paid to the patient as a whole, including comorbidities, before committing him or her to an invasive procedure. This observation after PCI is a reflection of a broader trend: the prevalence of comorbidities is increasing in the ever-older cardiology patient population,” he writes.

Proof of Progress

“We are starting to see plenty of evidence like this that heart disease is not the main cause of death in PCI patients anymore,” added Jeffrey W. Moses, MD, of Columbia University Medical Center/Weill Cornell Medical Center (New York, NY), in a telephone interview with TCTMD. Nonetheless, he said, having data that break down deaths into cardiac and noncardiac causes is important since many registries comparing outcomes for PCI and surgery patients assess only ‘all-cause mortality.’

“What isn’t acknowledged in this paper is that maybe improved PCI techniques have contributed to these findings,” Dr. Moses added. “This isn’t just about stents—it’s about [whether] we [are] more completely revascularizing than we have in the past and doing more procedures that are more pertinent to the disease process in these patients than we were 20 years ago. I suspect we are.”

He said despite the single-center nature of the study, the findings are robust enough to be generalizable to the overall US PCI population, although confirmation from larger patient groups, including STEMI and NSTEMI patients, is needed.

Dr. Moses added that such studies provide mortality information that clinical trials cannot, since often large clinical trials exclude patients with the type of significant comorbidities associated with noncardiac death.

Related Stories:

• New PCI Performance Measures Issued to Improve Quality of Care
• Updated Model Accurately Estimates Post-PCI Mortality Risk