Experts Debate Merits of Guideline-Directed Care for Patients With Multivessel Disease
When it comes to treating nondiabetic patients with multivessel CAD, there is considerable divergence in clinical practice from existing guidelines. While many clinicians support the guidelines and agree that available evidence supports the use of CABG in the majority of patients, others say there are good reasons to consider the more targeted approach conferred by PCI.
In an Interventional Issues discussion in the November issue of JACC: Cardiovascular Interventions, experts in this arena tackle both sides of the debate.
As proponents of the guidelines and appropriate use criteria (AUC), Pranav Kansara, MD, MS, and colleagues from Christiana Care Health System, (Newark, DE), say 5-year clinical and economic data from the SYNTAX trial demonstrate CABG to be superior to PCI in nondiabetic patients with 3-vessel disease and stable ischemic heart disease. In these patients with intermediate and high Syntax scores, CABG is more effective at reducing MACCE, MI, and repeat revascularization at a cost of $12,329 per quality adjusted life year gained, they add.
Kansara et al also note that the ASCERT registry study found that, despite an early advantage for PCI, there is a lower composite rate of stroke, MI, and death at 4 years with CABG vs PCI in patients with multivessel disease.
Old Data, Questionable Endpoints
But in their counterpoint, Matthew C. Hann, MD, and James Tcheng, MD, of Duke University Health System (Durham, NC), argue that the guidelines “are based on data more than 10 years old” and are “a priori applicable to less than one-half of patients with multivessel disease.”
They cite a number of inherent limitations in relying on the SYNTAX data, namely “the rapid and ongoing evolution of PCI techniques and technologies, rendering PCI-specific outcomes potentially outdated even before being considered in the creating of guidelines” and “the difficulties of applying general guidelines to decision making at the individual patient level.”
Yet another issue is the relevance of clinical trial composite endpoints to clinical care objectives.
“It was not until the endpoint of repeat revascularization (13.5% for PCI versus 5.9% for CABG; P < 0.001) was included in the primary endpoint of MACCE (17.8% for PCI vs. 12.4% for CABG; P = 0.002) that PCI failed to meet the noninferiority margin specified as the primary analysis,” Hann and Tcheng write, adding that symptom relief, an important endpoint for patients, is not represented in the composites.
“This salutary benefit is arguably of greater importance to the patient than a Kaplan-Meier demonstration of a reduction in mortality,” they say.
In a telephone interview with TCTMD, Kansara agreed that clinicians must consider the “patient as a whole,” taking into account age, comorbid conditions, and frailty. While the Syntax score is useful as an objective evaluation of the complexity of coronary disease, symptom relief is absolutely a major outcome of interest for patients and clinicians when treating with CABG, PCI, or medical therapy, he acknowledged.
Support for Innovative Approach
In the paper’s summary, moderator Lloyd W. Klein, MD, of Rush Medical College (Chicago, IL), adds that quality of life, relief from angina, recuperation time, and concern for permanent neurological damage are other patient-oriented endpoints that “are not easy to objectify” and are often not included as endpoints in RCTs.
According to Klein, an innovative approach to making the best decision for each patient is to consider the concept of value, which is defined as quality achieved per dollar spent.
“A promising tactic is to combine value with appropriateness,” Klein writes. “By including clinically defined outcomes, patient-expected outcomes, and relative cost in the equation, the ‘real value’ of a procedure to that patient might be objectively appraised.”
Importantly, Klein says, the economic and social consequences of using guidelines and AUC “as reasons to deny payment for a judiciously selected alternate strategy are troubling and scientifically completely unjustifiable.”
He recommends that future guideline panels “should avoid making strong recommendations when the best treatment strategy heavily depends on the patient’s context, goals, values, and preferences and should be reserved for evidence that demonstrates that 1 treatment option is definitely superior. When the evidence is conditional or less definitive, panels should indicate so and produce a provisional recommendation.”
Kansara agreed, adding that guidelines should never be broadly applied. “Very often you are faced with a patient [for whom] data from randomized trials is not applicable because that patient would never have been eligible for the trial in the first place,” he observed. “Guideline recommendations are great, but we know they have limitations.”
Despite the differences of opinion, he added, “it
all points toward the same idea, which is that we can’t treat everybody in the
same fashion. Syntax score should be taken into account, but it is not all
there is [to being a good cardiologist].”
Kansara P, Weiss S, Weintraub WS, et al. Clinical trials versus clinical practice: when evidence and practice diverge—should nondiabetic patients with 3-vessel disease and stable ischemic heart disease be preferentially treated with CABG? J Am Coll Cardiol Intv. 2015;8:1647-1656.
- Kansara, Hann, Tcheng, and Klein report no relevant conflicts of interest.
- SYNTAX Analysis: MI-Related Deaths More Common With PCI vs. CABG
- BEST: Due to Less TVR, CABG Still Favored Over PCI in Patients with Multivessel Disease
- Study Examines Influence of Baseline Factors on Outcomes After CABG, PCI