Percutaneous coronary intervention (PCI) and coronary artery bypass graf (CABG) are widely used revascularization interventions to treat atherosclerotic heart disease, but the merits of these procedures in patients with chronic kidney disease (CKD) are largely unknown, explains David M. Charytan, MD, MSc. “Since people with advanced CKD have high rates of cardiovascular morbidity and mortality, randomized controlled trials comparing these interventions typically exclude these patients,” he adds.

While the risk of acute kidney injury following PCI and CABG has been well characterized, little is known about the risk of progression to end-stage kidney disease (ESKD) following these procedures. “Avoiding progression to ESKD is an important goal for patients, because they do not want to go on dialysis,” says Dr. Charytan. “Other clinical factors, such as surgery and infection risks, can also drive clinical decision making between PCI and CABG in patients with CKD.”

Addressing an Important Unmet Need

For a study published in Kidney International, Dr. Charytan and colleagues sought to better define risks for all-cause mortality and progression to ESKD following PCI or CABG in the setting of CKD. They used data from Massachusetts residents with CKD undergoing PCI or CABG from 2003-2012 who were linked to the United States Renal Data System. They then analyzed associations with death, ESKD, and combined death and ESKD.

The study included data on 17,494 patients with CKD who received PCI and 6,805 who received CABG. Among 3,775 matched-pairs, multi-vessel disease was present in 97% of cases. Of note, stage 4 CKD was present in 12.2% of patients who underwent PCI and in 11.9% of those receiving CABG.

Confirming CABG Survival Benefits

The 1-year mortality rates for PCI and CABG were 11.0% and 7.7%, respectively. Approximately 1.7% of PCI recipients and 1.4% of those undergoing CABG later developed ESKD. Patients receiving CABG had better overall survival rates and an overall lower risk of ESKD progression than those who underwent PCI, but these effects differed depending on the presence of certain anatomic factors and the clinical scenario.

Survival was worse for patients receiving PCI than for those undergoing CABG among people with CKD who had left main disease and for those without myocardial infarction. The risk of ESKD progression was higher with PCI for patients who had left main disease and a prior infarction (Table). “Our findings confirm that the superiority of CABG to PCI is dictated by anatomic risk factors and the patient’s clinical scenario,” notes Dr. Charytan. “The greatest survival benefits with CABG were seen in patients with left main disease.”

Framing Clinical Decision Making

Currently, there is no universally preferred cardiac revascularization procedure for patients with moderate to advanced CKD. As such, the standards used in the general population are also applied to people with CKD. PCI may be a reasonable strategy when a patient’s background cardiovascular risk is low and there is no evidence of high-risk anatomy. On the other hand, CABG may be preferred when high-risk anatomic features, particularly left main disease, are present.

Although the risk of ESKD progression is critically important to many patients, the study data show that absolute rates of ESKD progression are low regardless of the procedure received., such that choices between PCI and CABG are unlikely to have a substantial impact on long-term risks for progression to ESKD. “There is no ‘cookie cutter’ answer, so it’s critical to take an individualized treatment approach when managing patients with moderate to severe CKD,” Dr. Charytan says.

With the exception of patients with CKD who have very strong preferences for avoiding progression to ESKD, Dr. Charytan recommends framing treatment decisions with patients in terms of the intervention’s impact on all-cause mortality. “If patient preferences are equally weighted between mortality or progressing to ESKD, clinicians should prioritize the effects of mortality when deciding between PCI and CABG,” he says.