SAN DIEGO – A simplified version of the SYNTAX score for coronary artery disease complexity strongly correlated with the unmodified SYNTAX score and could make it easier for cardiologists to employ it in everyday practice. The modified version can be easily memorized and has simplified values that a clinician can calculate and use to determine an appropriate treatment without breaking their work flow to consult a computerized system.
“It’s primarily simplifying the values for the location of the lesions that has allowed it to be more memorizable. That does make it a slightly blunter tool, but only slightly,” said Sonya Burgess, MBCHB, during a presentation at the Transcatheter Cardiovascular Therapeutics annual meeting. Dr. Burgess is an interventional cardiologist at the University of New South Wales, Sydney.
In common practice, SYNTAX scores often go uncalculated because of their complexity, despite guidelines that recommend it. “My guess might be that 1 in every 10 [cardiologists] do it, and that’s not right for our patients,” said Dr. Burgess.
Others at the session agreed that SYNTAX is underutilized, but not all agreed with Dr. Burgess’ solution. Notable among the attendees was Patrick Serruys, MD, of Erasmus University, Rotterdam, the Netherlands, who originally published the SYNTAX system. He doesn’t like the idea of simplifying SYNTAX, based in part on previous experience. “About 10 years ago, Boston Scientific found the score too difficult and they wanted to simplify it, but the score completely lost its prognostic value. I was very emotional about that and I said, ‘no, we have to keep all of the components until we understand [the risk factors] much better,’ ” said Dr. Serruys.
But Dr. Burgess argued that the simplified system, which she and her coinvestigators created, makes concessions to the realities of an interventional cardiology suite. To obtain a standard SYNTAX score, “they have to stop doing something or rebook something, or there’s a lesion there that they just want to treat. [With the simplified score], at least before they go on to treat that lesion, they don’t have to take their gowns and gloves off. You can even have a card hanging on the bar [to refer to].” Dr. Burgess did not provide details of the system.
Dr. Serruys agreed with the source of the problem. “Dr. Burgess is right, it is somewhat demanding,” he allowed, but he also called on clinicians to consider the needs of the patient, even going so far as picturing the patient as a family member. “People complain that doing the SYNTAX is on average 7 minutes, with a standard deviation of 7, so you could work 15 minutes just looking at film. But when you think that the future of your father or brother is depending on the surgeon and the cardiologist looking carefully, I find the argument absolutely obnoxious,” said Dr. Serruys at the meeting sponsored by the Cardiovascular Research Foundation.
Rather than simplification, he stresses teamwork. With at least three people looking at the angiogram, the results are consistent and useful. “You look at the film with the trainees, and that’s how they learn. Never do a SYNTAX score alone,” said Dr. Serruys.
To assess the simplified SYNTAX score, the researchers conducted a retrospective assessment of both the SYNTAX score and the simplified SYNTAX score in 617 patients who had multivessel disease. They performed both assessments in subgroups of patients with 169 patients with ST-segment elevation MI, 78 patients with chronic total occlusion, and 113 patients with left main coronary artery (LMCA) stenosis. They used a 100-patient derivation cohort to determine cutoffs for patients who would not be suitable for percutaneous coronary intervention. They also looked at the accuracy of the simplified version compared with standard SYNTAX in 517 patients from five tertiary centers.
The Spearman’s rho value was 0.93 overall and at least 0.91 for all subgroups (P less than .001 for all). In patients with LMCA stenosis, the simplified version had a sensitivity of 100%, specificity of 85%, negative predictive of 100%, and an area under the curve of 1.0 (P less than .001). For patients with multivessel disease and no LMCA stenosis, the values were 98%, 82%, 99%, and 0.971, respectively (P less than .001).
Dr. Burgess and Dr. Serruys reported no financial conflicts of interest.