Upstream Care Lacking for Many CTO PCI Patients in VA Health System

Fewer than half of US veterans receiving PCI for chronic total occlusions (CTOs) are managed according to clinical guidelines prior to the intervention, including being on at least two antianginal medications and undergoing stress testing in the preceding 3 months, according to new data from the Veterans Affairs (VA) Healthcare System.

The findings highlight an opportunity to improve care and “standardize upstream management” for this complex patient population, according to Stanley A. Swat, MD (Rocky Mountain Regional VA Medical Center, Aurora, CO), and colleagues. However, they point out that the reasons for treatment gap may be justified.

“There are several possibilities that may be contributing to these lower rates of antianginal and ischemic evaluations before PCI attempt,” they write. Challenges around titration of medical therapy are well documented, and while preprocedural stress testing might help determine the significance of epicardial stenoses, it may not be as helpful for CTOs, according to the authors. Also, procedural success rates in this study were similar to those seen in community settings, which hints had a different “risk-benefit balance” here.

“However, our study demonstrated significant variation at both operator and site level for upstream management, irrespective of patient factors, suggesting that local culture of practice and care continue to carry influence when patients proceed to invasive management of CTOs,” Swat and colleagues write.

In an accompanying editorial, Allison L. Tsao, MD, and William E. Boden, MD (both VA Boston Healthcare System), acknowledge VA data lean toward a “majority white, male population,” a demographic limitation that can pose to the generalizability of the study findings. Nevertheless, they write, the new results “reveal a striking, real-world picture of current academic VA medical practice with a low implementation of OMT [optimal medical therapy] for stable ischemic heart disease patients undergoing procedurally complex and often high-risk CTO PCI procedures. These are rather discouraging findings that signal a continued bias in how many cardiologists weigh the relative risks and benefits of PCI and OMT.”

The lack of medication use seen in the study is likely not specific to the population of CTO PCI patients nor the VA population, according to Tsao and Boden, “but more likely reflects a persistent, concerning trend observed in the overall management of angina patients in the United States.”

Commenting on the findings for TCTMD, Lorenzo Azzalini, MD (University of Washington Medical Center, Seattle), said the broader implications of the findings are not so black and white.

“Although I acknowledge that we should strive to do a better job with the optimization of medical therapy and making sure that the patient is worked up correctly, I think there is ample data showing that CTO PCI adheres to the appropriateness use criteria and meets recommendations more frequently than PCI for nonocclusive disease,” he said.

VA Data

For the analysis, the researchers evaluated 4,250 patients undergoing attempted CTO PCI within the Veterans Affairs Healthcare System—across 67 institutions and 248 operators—between 2012 and 2018.  Their mean age was 66 years, 99% were male, and 84% were white.

Overall, 40.4% of patients were prescribed at least two antianginal medications before their procedure, and preprocedural stress testing was performed within 3 months of the procedure in 24.1% of cases. Only 8% of the cohort met guideline-directed care standards of receiving at least two antianginals and undergoing preprocedural stress testing.

The vast majority of CTO PCIs (89%) were successful, and the rate of success did not differ based on preprocedural care. Over time, there was no change in the chances of a patient receiving more than one antianginal medication before CTO PCI (OR 1.0; 95% CI 0.97-1.04) or receiving both antianginal therapy with at least two medications and stress testing (OR 0.98; 95% CI 0.93-1.04). However, the odds of preprocedural stress testing decreased (OR 0.97; 95% CI 0.93-0.99).

The researchers observed significant variability at both the hospital- and operator-levels for both antianginal therapy (median OR 1.3; 95% CI 1.26-1.42 for hospitals and 1.35; 95% CI 1.26-1.63 for operators) and preprocedural stress testing (median OR 1.68; 95% CI 1.58-1.81 and 1.80; 95% CI 1.56-2.38).

Additionally, sensitivity analyses found similar results when the cohort was expanded to patients who received stress testing within 12 months before their CTO PCI and when limited to only those who had successful CTO PCI.

The Case for ‘Nuance’ in Interpretation

In their editorial, Tsao and Boden conclude with a call to action for operators to resist “favor[ing] lesion revascularization over intensive, proven OMT approaches. There is no question that maximizing antianginal medications and secondary prevention measures should be initiated before accepting the potential risks of CTO PCI, and we hope that as the technical advances continue to improve the safety and efficacy of interventional procedures, we do not lose sight of the fundamental goal of improving cardiovascular outcomes for our patients.”

Azzalini agreed that care of CTO PCI patients can be improved in general but pointed to “a lot of nuances in the interpretation of these study findings.”

First, he said, patients often have intolerances to beta-blockers, calcium channel blockers, or nitrates that would impede them being able to take at least two antianginal medications. Also, referral patterns can lead to patients undergoing stress testing within 4 to 5 months of their CTO PCI, and not always within the 3-month window that the study defined, Azzalini noted, adding that such testing might not even be deemed necessary given other factors of clinical presentation.

He would like to see a similar study performed in the general CTO PCI population, perhaps with National Cardiovascular Data Registry (NCDR) data, to confirm that patterns of care are similar outside the VA, as previous registry studies have focused more on procedural technicalities and outcomes than preprocedural care.

“If these findings of this study from the VA system are replicated in NCDR, we can identify points of improvement to ensure that we do a better job of at least documenting why the patient is just on one antianginal,” Azzalini said. “Also, the reasons why the patient is not on optimal medical therapy according to guidelines should be documented. This is also something we should be able to specify, and this registry should have some more granularity in their reporting.”