Stroke Incidence Related to PCI Steady for 15 Years
By Susan Jeffrey
Medscape Medical News
November 20, 2009 (Orlando, Florida) — Mayo Clinic researchers are reporting that rates of stroke and transient ischemic attack (TIA) related to percutaneous coronary intervention (PCI) at their institution have remained steady during the last 15 years at approximately 0.39%.
They interpret the results as good news. "Despite the fact that we're dealing with an older, sicker population, with more complex disease, the incidence of PCI-related stroke remains unchanged," senior author Rajiv Gulati, MD, PhD, from the Mayo Clinic Foundation in Rochester, Minnesota, told Medscape Neurology.
At highest risk were older women; those with recent myocardial infarction (MI), intracoronary thrombus, or significant renal impairment; and those undergoing multivessel PCI, Dr. Gulati reported.
"This gives us the ability to identify people at higher risk, and then forewarned, we can be on the look out for stroke when it does happen and activate our protocols immediately to try and deal with the event," he said.
Their results were presented here at the American Heart Association 2009 Scientific Sessions.
PCI-Related Stroke Steady
Studies have shown decreases in early mortality and composite major adverse cardiac events with PCI over time, but stroke, among the most feared outcomes because of its association with disability, has remained steady, the authors note. The incidence of periprocedural stroke in PCI registries has ranged from 0.15 to 0.44.
In this study, Dr. Gulati and colleagues aimed to determine temporal trends and predictors and look at in-hospital and long-term outcomes of strokes related to PCI at their institution. They performed a retrospective analysis of the Mayo Clinic catheter laboratory database of all patients who underwent PCI between 1994 and 2008.
During that period, 17,249 patients had 21,502 hospitalizations for PCI. They identified all cases of stroke or TIA related to these procedures and then compared these cases with patients without stroke or TIA as controls.
PCI-related stroke was defined as events usually within 48 hours of the procedures, diagnosed clinically by a neurologist and/or using imaging, with independent adjudication of the events by a neurologist when the diagnosis was unclear. Some stroke could have been missed using this method, they acknowledge, such as those secondary to death or cases in which stroke symptoms were not recognized as such.
"We found there were 84 cerebrovascular events or about a 0.39% risk with coronary angioplasty," Dr. Gulati said. Of these, 19 or 23% were TIAs.
Most strokes (92%) were ischemic, 6% were hemorrhagic, and 2% were of unknown origin. All but 1 were confirmed by either computed tomography or magnetic resonance imaging.
Most events (58%) were in the anterior circulation, with another 23% in the posterior circulation; 13% involved both the posterior and anterior circulation.
"We looked at temporal trends over the 15 years and, I think quite interestingly, found that the risk of stroke from year to year didn't change at all over this period," Dr. Gulati noted. "So despite the fact that we're dealing with a sicker population, older, with more complex disease, the incidence of a PCI or angioplasty-related stroke remains unchanged."
Demographic and procedural factors that independently predicted increased stroke risk were as expected, he noted, and included older age, female sex, MI within 7 days before the procedure, previous stroke, intracoronary thrombus, and multivessel PCI.
Stroke related to PCI was also associated with a significant increase in in-hospital mortality, increasing the risk from 1.8% in those without stroke to 20.2% (P < .001).
"Importantly, [in] people who did survive this stroke in-hospital, the presence of a stroke did confer a higher mortality over the next 10 years," Dr. Gulati added. The finding missed statistical significance after adjustment for other variables (P = .15).
"In some ways this is not surprising, because they were older, sicker people to begin with, but I think it's important information showing that having a stroke related to PCI confers a high risk of in-hospital mortality and also correlates with mortality over the subsequent 10 years," he added.
Comorbid Conditions
Asked for comment on these findings, Ralph Sacco, MD, from the Miller School of Medicine at the University of Miami in Florida and president-elect of the American Heart Association, said that although this study is from a single center, the investigators reviewed a large number of patients and confirm a relatively low risk of stroke after PCI, which appears to be stable for 15 years.
"Despite likely changes in technology, the stroke risk has remained stable, which implies that stroke risk is probably associated with comorbid conditions rather than the procedures themselves," Dr. Sacco told Medscape Neurology.
The study also helps identify some possible predictors of stroke in high-risk patients, including older age, female sex, prior stroke, recent MI, multivessel procedures, and intracardiac thrombus, with the greatest risk found among those with prior stroke older than 80 years.
"The study adds to our knowledge of the risk, determinants, and long-term outcomes of peri-PCI stroke," he concluded.
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Dr. Gulati and Dr. Sacco have disclosed no relevant financial relationships.
American Heart Association (AHA) 2009 Scientific Sessions: Abstract 4298. Presented November 16, 2009.
