February 22nd, 2013
SYNTAX After 5 Years: Any Change in Results (or Your Practice)?
Richard A. Lange, MD, MBA and L. David Hillis, MD
The 5 year results of the SYNTAX (SYNergy between percutaneous coronary intervention with TAXus and cardiac surgery) trial are now published. SYNTAX assessed the optimal revascularization strategy for patients with left main and/or 3-vessel disease by randomly assigning such patients to CABG or PCI (with a first-generation paclitaxel-eluting stent) and then determining the rate of major adverse cardiac and cerebrovascular events (MACCE, defined as all-cause mortality, stroke, myocardial infarction, and repeat revascularization).
The 5 year follow-up data confirm the 1 year and 3 year results. The “bottom line” conclusions are:
1) CABG should remain the standard of care for patients with complex lesions (i.e., SYNTAX scores that are intermediate [score, 23-32) or high [score, > 33].
2) For patients with 3-vessel disease considered to be less complex (i.e., a SYNTAX score < 22) or left main disease with a SYNTAX score considered to have a low or intermediate score (i.e., < 32), PCI is an acceptable alternative.
3) All the data from patients with complex multivessel CAD should be reviewed and discussed by a cardiac surgeon and an interventional cardiologist, after which consensus on optimal treatment can be reached.
The fine points…
1) In patients with a high SYNTAX score (> 33), the CABG group had lower mortality than the PCI group.
2) In subjects with an intermediate SYNTAX score (23-32), mortality rates were similar in the 2 treatment groups, but MACCE was higher with PCI than CABG (due to increased rates of MI and repeat revascularization).
3) In patients with low (0-22) SYNTAX scores, MACCE rates did not differ between CABG and PCI.
4) About two-thirds of those with complex CAD are best treated with CABG.
SYNTAX II….the nomogram that may bring you to tears….
Vasim Farooq and colleagues describe the SYNTAX score II, which quantifies the risks and probable outcomes of CABG or PCI in individual subjects by combining the purely anatomical SYNTAX score with clinical variables. The SYNTAX II score — based on 2 anatomical variables (SYNTAX score and presence of left main disease) and 6 clinical variables (age, gender, creatinine clearance, LV ejection fraction, chronic obstructive pulmonary disease, and peripheral vascular disease) — provides a more accurate prediction of early and long-term outcomes with PCI or CABG than the SYNTAX score….unless you are “nomographically challenged” (to see what I’m talking about, look at the nomogram shown in Figure 4).
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Okay, let’s be honest….
1. In your hospital, in what percentage of patients with left main or 3 vessel CAD are all the data systematically reviewed and discussed by a “Heart Team”?
2. Do you calculate SYNTAX on all patients with left main or 3 vessel disease, or do you usually just “guestimate” lesion complexity?
Lange and Hillis, my two esteemed colleagues, seem to be encouraging our readers to calculate the SYNTAX score. But I wonder what they thought of the 2011 article that suggested that the SYNTAX score can only be calculated accurately by angiographic core labs. And the data upon which these articles are based derived from core lab measurements. Here is the citation. If interventional cardiologists cannot accurately and reproducibly calculate this score, then do we need to develop an approach they can use?
SYNTAX score reproducibility and variability between interventional cardiologists, core laboratory technicians, and quantitative coronary measurements.
Généreux P, Palmerini T, Caixeta A, Cristea E, Mehran R, Sanchez R, Lazar D, Jankovic I, Corral MD, Dressler O, Fahy MP, Parise H, Lansky AJ, Stone GW.
Circ Cardiovasc Interv. 2011 Dec 1;4(6):553-61. doi: 10.1161/CIRCINTERVENTIONS.111.961862. Epub 2011 Oct 25.
PMID: 22028472 [PubMed – indexed for MEDLINE]
I don’t know any cardiologists who calculate the Syntax score routinely. In the real world do people really have the time, the patience and the skill?
Furthermore, although there were clear differences, many patients faced with the prospect of a day in hospital and a small incision in the wrist (hopefully) vs. 5-7 days in hospital and 3 months convalescence, will choose PCI over CABG. People are excellent at believing “it won’t happen to me”.
Finally, can someone remind me of the long term significance of peri-procedural MI? Clearly no-reflow down the LAD with a significant infarct is one thing, but occlusion of a small side branch with a minimal troponin rise is something else.
I am not an interventionalist, and clearly trials like this emphasise that PCI is not appropriate in all cases and CABG has a role, but I’m not sure this trial will change practice profoundly in many institutions.
For me, the biggest question is not PCI vs. CABG, it’s more who do we really need to revascularise, by whatever method, particularly those without symptoms or with difficult “angina equivalent” symptoms such as breathlessness.
In our CathLab we do not routinely calculate the Syntax Score, but we do refrain from doing multi-vessel adhoc PCIs mainly to allow for a heart team discussion of every complex patient. The only time we would calculate the SYNTAX score is when counseling patients who refuse CABG so we could show them with numbers their predicted outcomes, or when the “guesstimate” is very different between the surgeons & interventionalists.
Of course it’s changed practice (and so has the FREEDOM trial). After Syntax, patients with VERY complex disease (usually translates to a Syntax score above 25) do get offered CABG as a first option. Whether the accept CABG or not, it’s up to them but unless it’s an adamant and categorical “HELL NO!” on the table, these patients get to speak to a surgeon first and then come back for PCI if they truly decline. Contrary to “popular” thought (often promoted by the interventional community) patients usually are able to think beyond the “sliced chest vs. nick in the wrist” argument and make a decision (both in the US as well as in Asia). I personally don’t calculate the Syntax score (too tedious – admittedly a weak argument) but usually it’s pretty clear which angiogram is a high and which is a low score.
This highlights a gap in our current science: how do our variable presentations of the data influence patient choice? And importantly, how can we do better? An abstract at this meeting by Kashef and Rothberg begins to shed light on our understanding of our role in patient choice, even when we think we may present a case of equipoise. Furthermore, the field of shared decision making is slowly growing, including the development of tools that assist us in our communication of complex data and ensure that we gather patient goals and preferences to help guide choice.
Definitely agree with the above. The knowledge we have gained for how to risk stratify patients to guide treatment have far outpaced our ability to apply risk stratification in actual patients. Perhaps what we need is a new field kind of “translational” research: in addition to “bench to bedside”, should we also place more emphasis on “risk score at the bedside”?