PCI and CABG Are Complementary Options for Left Main CAD, Say Experts

(UPDATED) If there’s an area of cardiology in need of reconciliation, revascularization of left main coronary artery disease would be a worthy candidate given the acrimony of the past few years.

Now, three physicians—a surgeon, a clinical cardiologist, and an interventionalist—attempt to bridge the divide between surgery and interventional cardiology by recapping the evidence in support of the different revascularization strategies for patients with left main disease.

In their new viewpoint, published April 22, 2022, in the European Heart Journal, Mario Gaudino, MD (Weill Cornell Medicine, New York, NY), Michael Farkouh, MD (University Health Network/University of Toronto, Canada), and Gregg Stone, MD (Icahn School of Medicine at Mount Sinai, New York, NY), say the hope is that the “united perspective” will provide a “framework to reconcile prior disparate opinions and serve to ‘reunite’ the subspecialties in the best interest of our patients.”

The bottom line, say the trio, is that “the two interventions should not be viewed competitively, but rather as complementary.”

As the clinical cardiologist in the group, Farkouh stressed that all three specialties are members of the heart team and that this team-based approach for left main CAD benefits all involved, particularly patients.

“We manage a lot of patients before the procedure and are often involved in postprocedure, secondary-prevention care,” he told TCTMD. “It’s in our best interest to have a positive, constructive heart team approach in order for us to provide our patients with the best possible care. We’re intimately involved in informing patients of the benefits and risks of these procedures.”

Competent and well-informed adults will value different aspects of medical treatment differently. Gregg Stone

Stone said the viewpoint emphasizes the importance of placing the patient at the center of the heart team, noting that cardiology has entered into an era of patient-oriented decision-making.

“Competent and well-informed adults will value different aspects of medical treatment differently,” he told TCTMD. “They have different life values, different goals. With respect to coronary revascularization for left main coronary artery disease, some patients may place a great value on the early quality of life benefits and procedural benefits of PCI, while other patients may place greater value on the long-term durability of bypass surgery compared with PCI. We believe the event-rate data and quality-of-life data reflect those differences.”

While patients might inherently know the two procedures differ in terms of early recovery and long-term durability, “we now have the science behind those beliefs and are able to tell patients what to expect—the magnitude of the likely differences—and can help them make an informed decision,” said Stone.

Recapping All Available Evidence

In the past few years, there has been no shortage of debate about the relative risks and benefits of PCI compared with CABG surgery for left main CAD. That controversy began in earnest with the EXCEL trial, specifically the 5-year outcomes showing that PCI was associated with a significantly higher risk of all-cause mortality. There were accusations that these mortality data were downplayed, by none other than the study’s surgical chairman, and that MI events were deliberately buried to cast PCI in a more-favorable light.

These allegations were vociferously denied by the EXCEL researchers, including by Stone, who served as the study’s lead investigator. In their wake, the European Association for Cardio-Thoracic Surgery (EACTS) pulled their support from the European Society of Cardiology (ESC) revascularization guidelines for left main CAD and called for an independent review, one that is currently ongoing.    

In November at the American Heart Association 2021 Scientific Sessions, independent investigators led by Marc Sabatine, MD, and Eugene Braunwald, MD (Brigham and Women’s Hospital, Boston, MA), attempted to unravel the data from personal opinion by conducting a patient-level meta-analysis of the published studies of left main CAD. That analysis, which included EXCEL, NOBLE, SYNTAX (left main cohort only), and PRECOMBAT, was facilitated by the ESC with the goal of informing the European revascularization guidelines for left main CAD.

The new viewpoint recaps all of this evidence, including the mortality data. For patients considered eligible for either PCI or surgery, “the evidence from four large-scale randomized trials has demonstrated that long-term differences in major outcomes (death, stroke, and large MI) and quality of life after PCI and CABG are small, and thus the early vs late trade-offs of the procedure (safety profile of PCI vs durability of CABG) should inform clinical decision-making,” state Gaudino, Farkouh, and Stone.

It’s in our best interest to have a positive, constructive heart team approach in order for us to provide our patients with the best possible care. Michael Farkouh

To TCTMD, Stone said that the care of patients with left main CAD—or any disease, for that matter—is based on the totality of evidence. The independent, patient-level meta-analysis was an attempt to reconcile many of the controversial issues surrounding left main revascularization that arose over the past several years.

“Actually, I would say it left the realm of pure science and was overtaken by other, non-medical-related issues,” he said.  

The three authors, said Stone, don’t speak for the subspecialties, but he noted that all three have led many important trials of CAD revascularization. As representatives of the heart team, they viewed the totality evidence in a similar way, he said. Stone reiterated that PCI and CABG surgery should be considered as complementary procedures, particularly since the trials included only patients where there was clinical equipoise.    

“For many patients—I would say more than half of patients—there is not going to be equipoise,” he said. “Either coronary anatomy would be so complex that nearly all physicians would agree that bypass surgery is the best treatment for the patient. In other cases, the patient’s clinical comorbidities would put them at such high risk should they undergo a surgical procedure with anesthesia that the vast majority of physicians would believe they’re appropriate for PCI. It’s important to not lose that perspective.”

‘Feel-good Vibe’

Cardiovascular surgeon Faisal Bakaeen, MD (Cleveland Clinic, OH), called the viewpoint an “interesting and catchy essay with a feel-good vibe,” adding that physicians are likely to appreciate unified recommendations from a surgeon, clinical cardiologist, and interventionalist on how to best revascularize patients with left main CAD. 

Still, Bakaeen said the viewpoint doesn’t provide any new information beyond the robust scientific contribution from Sabatine and colleagues at the TIMI group. Some of the language is also “nebulous,” he said, noting that the higher 5-year mortality with PCI in EXCEL was chalked up to chance. Moreover, he observed that the timing of the viewpoint’s publication is “curious,” because the ESC guidelines are currently being revised and it’s unusual to preempt that process.

“I hope that the writing committee will stay focused and objective and reconcile the recommendations to the best available evidence,” said Bakaeen.

Like the viewpoint authors, Bakaeen agrees that CABG and PCI should be viewed as complementary procedures, but said there are areas where the evidence isn’t very robust. “Frailty and high physiologic risk favor a PCI option,” Bakaeen told TCTMD. “On the other hand, anatomic complexity and heavy atherosclerotic burden favor CABG. The aforementioned scenarios are excluded or underrepresented in randomized controlled trials comparing [left main] revascularization strategies.”

I hope that the writing committee will stay focused and objective and reconcile the recommendations to the best available evidence. Faisal Bakaeen

On the whole, Bakaeen stressed the durability of CABG surgery in the treatment of left main CAD. Absent a medical regimen that leads to atherosclerotic lesion regression, a left internal thoracic artery graft to the left anterior descending artery (LITA-LAD) provides the most-reliable and -durable revascularization option. “We are not talking 5 years or 10 years here. We are talking decades—a lifetime, actually,” he said. “The patient can only make the right choice if the associated benefits and risks are clearly spelled out to them in an unbiased and objective manner.”

Stone said that while the viewpoint recaps the data with respect with major adverse cardiovascular events, it also includes information about recovery and quality of life with the two procedures. Physical and psychological discomfort is higher after CABG and recovery is prolonged, and this may affect patients’ decisions. Beyond 1 year, both treatments achieve similar improvements in quality of life and angina relief, say the trio.

“This is a very important part of the viewpoint, because it often drives patient decisions about whether to undergo PCI or CABG,” said Stone. “In this regard, we actually have several, high-quality databases that address early and late quality of life after the procedures that we think are important to consider.”

Need for Collaboration to Best Treat Patients

To TCTMD, Farkouh said the contentiousness in the field the last few years stemmed from the genuine desire on both sides to provide the best evidence possible to guide patient care. “What we fail to realize—and I’ve learned a lot from Gregg Stone and Mario Gaudino on this—is that one size doesn’t fit all,” said Farkouh. “When we do a trial, we randomize a patient to one intervention or another, we don’t really capture the nuances that go into the decisions needed to get to that point.”

He also noted that from a research perspective, the different groups all must work together, just as they have in the past. Farkouh said he’s had nothing but excellent working relationships with surgeons and interventionalists, adding that his research in ischemic heart disease wouldn’t be possible without such collaboration.

In terms of the viewpoint’s timing, Farkouh said the publication was intended to bridge two distinct camps when it comes to revascularization for left main CAD. Surgeons believe their approach should be preferred, while more and more patients were being evaluated for PCI and achieving good success. “The results of the trials were somewhat inconsistent with one another if you look at NOBLE and EXCEL, and we needed to come to a consensus so we can move forward here without being isolated in one camp or the other,” he said.

In late 2021, the American College of Cardiology and American Heart Association (ACC/AHA), in partnership with the Society for Cardiovascular Angiography and Interventions (SCAI), issued new revascularization guidelines, awarding surgery a class 1 (level of evidence B) recommendation for patients with significant left main stenosis. PCI has a class 2a (level of evidence B) indication for selected patients of low-to-medium anatomical complexity.

The ACC/AHA/SCAI guidelines were also not without controversy, with neither the American Association for Thoracic Surgery (AATS) nor the Society of Thoracic Surgeons (STS) formally endorsing the recommendations. Their grievances about the guidelines mainly revolve around the decision to downgrade surgery from a class 1 to 2a recommendation in patients with multivessel CAD. However, the surgical groups also expressed concern about the failure to recognize the superior long-term advantages of CABG surgery over PCI for reducing postprocedural MIs and the need for repeat revascularization.