PCI use, survival trending up for elderly STEMI patients with cardiogenic shock

Percutaneous coronary intervention is being offered to a greater proportion of older adults with ST-segment elevation myocardial infarction (STEMI) complicated by cardiogenic shock over the past two decades—a trend that’s been paralleled by declining mortality rates, according to a study in the Journal of the American College of Cardiology.

More than 10% of STEMI patients older than 75 develop cardiogenic shock, a condition with a mortality rate reported as high as 79%, wrote lead author Abdulla A. Damluji, MD, MPH, and colleagues.

While early revascularization with PCI was proven in the 1999 SHOCK trial to be beneficial in younger patients with STEMI and cardiogenic shock, the results for those 75 and older were less conclusive.

To better investigate the relationship between PCI and in-hospital mortality for these elderly patients, Damluji et al. used the National Inpatient Sample to identify 111,901 cases of STEMI complicated by cardiogenic shock among patients 75 or older between 1999 and 2003.

They found the rate of PCI utilization for these patients increased from 27% to 56% from 1999 to 2013. Over that same timeframe, unadjusted in-hospital mortality decreased from 64% to 46%.

In addition, the researchers propensity-score matched patients who received PCI versus those who didn’t based on their cardiovascular comorbidities including hypertension, diabetes, obesity, valvular heart disease and peripheral vascular disease, among other factors. Even with the adjustments, receiving PCI decreased the odds of in-hospital mortality by 52%—including by at least 49% across four different U.S. regions (Northeast, West, Midwest, South).  

“This large and contemporary analysis shows that utilization of PCI in older adults with STEMI and cardiogenic shock is increasing and paralleled by a substantial reduction in mortality,” the authors wrote. “Although clinical judgment is critical, older adults should not be excluded from early revascularization based on age in the absence of absolute contraindications.”

Those potential contraindications include active bleeding, severe neurocognitive decline or limited life expectancy due to end-stage disease process, Damluji and colleagues noted.

Eliano P. Navarese, MD, PhD, suggested in a related editorial that recent improvements in PCI devices, techniques and care processes may have played a role in the study’s results.

“The progressive availability of newer stent-generation devices, shorter primary PCI time delays, as well as the increased use of radial access for STEMI, in turn carrying less bleeding risk, may have contributed to this observed decline in mortality with PCI over time,” they wrote.

Notably, the unadjusted mortality for those who underwent PCI in the analysis was higher if a patient had a bleeding event (34% vs 29%). An important next step, according to the editorialists, is identifying specific groups of elderly patients most likely to benefit from revascularization for STEMI with cardiogenic shock.

“The analysis by Damluji et al. supports the need for more robust (randomized controlled trials) in CS, particularly to study mechanical support devices that are currently widely used without adequate RCT data,” Navarese et al. wrote. “Robust real-word data are indeed warranted to provide evidence supporting more informed best practice for the growing elderly population in the United States.”