New Revascularization Guidelines Plug Radial Access, Staged PCI, and Shorter DAPT

The American College of Cardiology and American Heart Association (ACC/AHA) have issued new guidelines for the revascularization of coronary artery disease.

The recommendations, which were drafted in partnership with the Society for Cardiovascular Angiography and Interventions (SCAI) and published today in Circulation and the Journal of the American College of Cardiology, provide guidance for the revascularization of patients with STEMI, NSTE ACS, and stable ischemic heart disease (SIHD), and as well guidance on how to manage special populations, such as older patients and those with chronic kidney disease (CKD).

The guideline-writing committee, which was chaired by cardiac surgeon Jennifer Lawton, MD (Johns Hopkins Medicine, Baltimore, MD), stresses that all treatment decisions for coronary revascularization “should be based around clinical indications, regardless of sex, race, or ethnicity, because there is no evidence that some patients benefit less than others, and efforts to reduce disparities are warranted.”

Still, the recommendations are not free of the controversy that has dogged other recent consensus documents. The guideline-writing committee included a mix of surgeons and interventionalists, as well as general cardiologists, and an official representative from the American Association for Thoracic Surgery (AATS). But though the guidelines were reviewed by the AATS and the Society of Thoracic Surgeons (STS), neither formally endorsed the document.

In a brief statement to TCTMD, STS First Vice President John Calhoon, MD (University of Texas Health Science Center, San Antonio), confirmed that while STS was involved in developing the document, they decided not endorse the final recommendations. “The Society applauds the efforts to develop recommendations in this area, but disagrees with the interpretation of the scientific evidence,” he told TCTMD in an emailed statement.

Interventional cardiologist Jacqueline Tamis-Holland, MD (Icahn School of Medicine at Mount Sinai, New York), who served as vice chair of the writing committee, said the new guidelines are not “how to” directions regarding specific procedures, but instead should help physicians best manage patients with significant CAD requiring treatment.

“[These] guidelines are really about the patient, their condition, and how best to treat them knowing all of the available resources: medication, surgery, and stenting,” she told TCTMD. “We’re approaching this as, ‘This is what the patient has and how can we as a team address their issues to provide the best care?’ It’s really about what we can offer the patient to give them the best outcomes.”

Informed consent and a focus on patient-centered care to arrive at a collaborative decision about the best treatment approach are at the heart of the new revascularization recommendations, said Tamis-Holland. “It’s about taking the information and us working across disciplines to provide the patient with the best care,” she said.

TCTMD reached out to a range of cardiac surgeons involved at different levels of the writing committee, but all referred questions about the guidelines, including the lack of endorsement from the surgical societies, to the ACC/AHA. The AATS did not respond to requests for comment.    

An ACC/AHA spokesperson said that both the AATS and STS had representatives on the guidelines’ writing committee and actively participated in the writing process for the past 3 years. In addition, the surgical societies had a reviewer each who participated in the “extensive” peer review process. Ultimately the AATS and STS both elected not to endorse the guidelines once the process moved to the approval stage.

“Consequently, the AATS representative chose to stay with the committee and be recognized as having been appointed on behalf of the ACC and the AHA,” according to an emailed statement from the ACC/AHA. “The STS representative chose to withdraw from the committee and is not listed as a writing committee member on the final guideline. The final guideline reflects the latest evidence-based recommendations for coronary artery revascularization, as agreed by the ACC, AHA, SCAI, and the full writing committee.”

Practice-Changing Recommendations     

The 2021 ACC/AHA/SCAI guidelines are intended to replace or retire six existing guidelines, including those for PCI and CABG (2011), and the SIHD, STEMI, and NSTE ACS guidelines (2012, 2013, and 2014, respectively).

In terms of specific recommendations that may have an immediate impact on clinical practice, Tamis-Holland said one big change is the emphasis on a radial-first approach, both in ACS and SIHD patients undergoing PCI. Radial access is a class 1 indication (level of evidence A) to reduce the risk death, in the case of ACS patients, and to reduce the risk of bleeding and vascular complications in all patients.

“That’s a big deal, and it’s a strong recommendation,” said Tamis-Holland. “A lot of us are transitioning to radial access, but not everybody does it and not everybody does it in every situation.”

Additionally, the new guidelines emphasize shorter-duration dual antiplatelet therapy (DAPT) following PCI. In most patients, DAPT for 1 to 3 months is considered a reasonable option (class 2a, level of evidence A) to reduce the risk of bleeding events. The last update from the ACC/AHA on DAPT duration in patients with CAD was published before the shorter-duration DAPT trials, but the new revascularization guidelines take these into account, said Tamis-Holland.

Staged, complete revascularization after STEMI also gets a strong recommendation on the basis of the COMPLETE trial. In hemodynamically stable patients with STEMI and multivessel disease, staged PCI of a significant non-infarct-related artery after successful primary revascularization is recommended to reduce the risk of death or MI (class 1, level of evidence A). PCI of the non-infarct-related artery can be considered at the time of primary PCI in those with low-complexity, multivessel CAD (class 2b, level of evidence B). PCI of non-infarct-related arteries shouldn’t be performed in STEMI patients complicated by cardiogenic shock.

“We don’t endorse doing staged PCI in every single blockage of the noninfarct artery, but for physicians to focus on doing staged PCI in arteries that are big, maybe supplying a large area of heart muscle, and not doing it in patients who are going to succumb to increased risk,” said Tamis-Holland. “We’re not saying do staged PCI in someone with renal disease, or older patients who might not benefit, but for the most part the idea is to consider staged PCI.”   

Stable Patients

The guideline recommendations for stable patients are broken down according to whether the evidence supports an improvement in survival, or a reduction in cardiovascular events and/or an improvement in symptoms.

With mortality as the focus, CABG is recommended to improve survival (class 1, level of evidence B) in stable patients with multivessel CAD and severe left ventricular systolic dysfunction (LVEF < 35%), largely on the basis of the STICH trial.

Surgery is also recommended (class 1, level of evidence B) to improve survival for SIHD patients with significant left main stenosis. In contrast with the European Society of Cardiology’s left main recommendations, which are currently under review after the European Association for Cardio-Thoracic Surgery (EACTS) pulled their support, the ACC/AHA/SCAI awarded PCI a class 2a indication (level of evidence B) for selected patients with left main disease of low-to-medium anatomical complexity.

Ajay Kirtane, MD (NewYork-Presbyterian/Columbia University Irving Medical Center, NY), who wrote an editorial accompanying the new revascularization guidelines with surgeon Kendra Grubb, MD (Emory University, Atlanta, GA), believes the ACC/AHA/SCAI got the left main recommendations right.

“It’s exactly what I would have liked to see,” said Kirtane. “I think it’s perfectly in line with the data.” He noted that the guidelines include the provision that operators must be able to achieve comparable revascularization with surgery, and to be able to do that, “it’s got to be done by an experienced operator,” he said.

In stable multivessel disease, again with the lens of reducing mortality, CABG surgery has been downgraded from a prior class 1 recommendation to a class 2b (level of evidence B) recommendation based largely on new evidence from the BARI-2D and ISCHEMIA trials. According to the writing committee, the prior class 1 recommendation for surgery was based on registries, a meta-analysis, and trials 20 to 40 years old. PCI is also a class 2b recommendation (level of evidence B) in patients with stable, multivessel CAD, but the writing committee states that the mortality benefit with an invasive approach is “uncertain.”

To TCTMD, Tamis-Holland said there will never be another clinical trial testing CABG surgery versus medical therapy alone in SIHD patients with multivessel disease because of the absence of equipoise. She acknowledged that BARI-2D and ISCHEMIA were not designed to directly test CABG in this patient population, though indirect evidence has suggested patients did just as well with medical therapy.

“In ISCHEMIA, the question wasn’t exactly the same, and that’s why there’s some difficulty,” she said. “You have trials that are 30 and 35 years old saying one thing, and you could argue they’re outdated, but it’s the only evidence we have. The more recent trials don’t ask the specific question but tell us indirectly there may be a difference. You have to balance that.”  

Kirtane, for his part, was surprised to see CABG surgery downgraded from its prior class 1 indication in stable patients with multivessel disease.

“I understand why the committee did it,” he told TCTMD. “Some of the data is old, but it’s hard to overturn that data on the basis of the ISCHEMIA trial. ISCHEMIA randomized patients to an invasive or conservative strategy, not to revascularization versus no revascularization. When you consider that 20% of patients in the invasive strategy didn’t get revascularization, and of those who did, only one-quarter were treated with CABG, it’s hard to overturn some of that older surgical data.”

For a young patient with multivessel CAD, including a proximal LAD lesion, it’s hard to make the case that they won’t live longer with surgery over optimal medical therapy, said Kirtane. Nonetheless, he admitted that arriving at a consensus for the new recommendations was likely tremendously difficult and that many of the more recent trials are open to interpretation. 

The guidelines also provide some direction for patients with complex SIHD. In patients with multivessel disease considered complex or diffuse (SYNTAX score > 33), it is reasonable to choose CABG over PCI to confer a survival advantage (class 2a, level of evidence B). Surgery is also a class 1 indication (level of evidence A) for patients with diabetes and multivessel CAD that includes the LAD artery, but PCI can be useful if these patients are poor candidates for surgery.

In terms of reducing outcomes other than mortality in stable patients, the guidelines give CABG and PCI a class 2a indication (level of evidence B) to lower the risk of cardiovascular events, such as spontaneous MI, urgent unplanned revascularization, or cardiac death. That recommendation is based on results from MASS II, FAME-2, and different meta-analyses. Coronary revascularization is a class I indication (level of evidence A) to improve symptoms in patients with significant coronary stenoses and refractory angina.

STEMI, NSTE ACS, and Other Recommendations

In the setting of STEMI, PCI remains a class 1 indication to improve survival for patients who present within 12 hours, but it’s also considered reasonable for stable STEMI patients who present within 12 to 24 hours after symptom onset (class 2a, level of evidence B). PCI or surgery (if PCI is not feasible) is a class 1 indication in STEMI patients with cardiogenic shock or hemodynamic instability irrespective of symptom onset and rescue PCI is a class I indication after failed fibrinolytic therapy. PCI is not recommended for patients without ongoing symptoms or severe ischemia who present after more than 24 hours with a totally occluded infarct-related artery. 

In those with NSTE ACS, an invasive strategy with the intent of performing revascularization is recommended to reduce the risk of cardiovascular events (class 1, level of evidence A). It is also recommended for NSTE ACS patients in cardiogenic shock, those with refractory angina, or hemodynamic or electrical instability. An early strategy (within 24 hours) is a reasonable approach (class 2a, level of evidence B) in stabilized NTSE-ACS patients at high risk for ischemic events. It is also considered reasonable to revascularize before hospital discharge (class 2a, level of evidence B).

Finally, the new guidelines provide recommendations for taking care of patients with CKD, older patients, pregnant women, and those who present with spontaneous coronary artery dissection. Intravascular imaging also has a section in the document, with the ACC/AHA/SCAI writing committee suggesting that IVUS can be useful to guide procedures, particularly in cases of left main CAD or patients with complex anatomy. If IVUS isn’t available, optical coherence tomography (OCT) is a reasonable alternative.

The guidelines throw some cold water on the treatment of chronic total occlusions (CTOs), stating that the benefit of PCI for the improvement of symptoms is uncertain (class 2b, level of evidence B).

Hemodynamic support as an adjunct to PCI is considered reasonable for selected high-risk patients (class 2b, level of evidence B). 

To TCTMD, Kirtane said guideline-writing committees often make assumptions based on the average treatment effects in clinical trials and generalize these findings to routine clinical practice. That, however, doesn’t account for operator/surgeon experience. For instance, the 2b recommendation for revascularization of CTOs to reduce symptoms refractory to treatment may make sense broadly speaking, but experienced operators can achieve excellent results in treating these patients.

“Unlike medication, which is the same medicine if you prescribe it in New York or Chicago, procedures and operations aren’t like that at all,” he said. “I would have liked to see something in the guidelines around competency and experience.” Some of the surgical recommendations do account for competency, he noted, particularly around guidelines for use of arterial conduits and off-pump CABG surgery.

Kirtane and Grubb, in their editorial, said that they would like to see contingencies added to specific recommendations in the guidelines, such as “if performed by an experienced operator or surgeon.”

Overall, Tamis-Holland praised the writing committee, particularly Lawton for her role in the process, saying that there was a “lot of back and forth and a lot of differences in opinion.” That debate wasn’t limited to specialists in different fields, such as surgeons and interventionalists, but even among those within the same subspecialty.

“Dr. Lawton was an unbelievably equitable person who really tried to hear everybody’s opinion,” said Tamis-Holland. “She really included everybody and really valued everybody’s opinion.”