PCI linked to higher all-cause mortality than CABG in new meta-analysis

Percutaneous coronary intervention (PCI) is associated with higher rates of all-cause, cardiac and noncardiac mortality than coronary artery bypass grafting (CABG), according to a new meta-analysis published in JAMA Internal Medicine.

The authors reviewed 23 different clinical trials—and more than 13,000 unique patients—for their research. The mean patient age of those trials varied from 60 to 71 years old.

While some studies over the years have focused on all-cause mortality, others have been more concerned about cardiac mortality. Differentiating between those two primary outcomes, the authors noted, is incredibly important.

“The use of all-cause mortality reduces the risk of adjudication bias due to incomplete, skewed, or inadequate supporting evidence, but it has the potential to dilute the treatment effect due to the inclusion of events unrelated to interventions for the coronary circulation,” wrote Mario Gaudino, MD, Weill Cornell Medicine in New York City, and colleagues. “On the other hand, the use of cause-specific mortality reduces the event rate, is subject to bias, and can lead to underpowered comparisons.”

Gaudino et al. explored these differences, running the necessary analyses to determine that PCI was linked to an increase in all-cause mortality, cardiac mortality and noncardiac mortality after five years. A separate analysis of sensitivity confirmed the group’s findings.

In addition, PCI with drug-eluting stents was linked to higher all-cause, cardiac and noncardiac mortality when compared to bare-metal stents, “although the test for interaction did not reach statistical significance.”

“Observational evidence shows that the causes of mortality after PCI and CABG are predominantly cardiac in the first year after the procedure and noncardiac in the following years,” the authors wrote. “The common causes of cardiac mortality include cardiogenic shock, heart failure, stent thrombosis, bleeding, coronary dissection, malignant arrhythmia, and sudden death, whereas cancer, sepsis, bleeding, and vascular, pulmonary, and/or renal disease are among the most frequent causes of noncardiac mortality.”

Reviewing their findings, the authors concluded that using all-cause mortality as a primary composite outcome paints a more accurate picture than relying on cause-specific mortality.

“Based on our results, the use of cardiac mortality may exclude deaths that are in fact related to the procedure, either through noncardiac mechanisms or because of misclassification,” they wrote.

Read the full study here.