title: Residual SYNTAX score following coronary artery bypass grafting.
abstract: To quantify residual coronary artery disease measured using the SYNTAX score (SS) and its relation to outcomes after coronary artery bypass grafting (CABG).
  
  
  
  We conducted a retrospective analysis on a consecutive series of 1608 patients [mean age 68 years, standard deviation (SD): 7, F:M, 242:1366] undergoing first-time isolated CABG from 2004 to 2015. The baseline SS was retrospectively determined from preoperative angiograms, and the residual SS (rSS) was measured during assessment of the actual operative report for each patient after CABG. Patients were then stratified according to tercile cut points of low (rSS low 0-11, N  = 537), intermediate (rSS mid  >11-18.5, N  = 539) and high residual SS (rSS high  >18.5, N  = 532). The Cox regression model was used to investigate the impact of rSS on major adverse cardiac and cerebrovascular events (MACCE) at 1 year.
  
  
  
  The mean preoperative SS was 26.6 (SD: 9.4) (range 10.1-53), and the residual SS after CABG was 15.3 (SD: 8.4) (range 0-34) ( P  <   0.001 versus preoperative). At 1 year, cumulative incidence of MACCE in the low rSS was 1.5% ( N  = 8/537), 4.5% ( N  = 24/539) in the intermediate and 8.8% ( N  = 47/532) in the high rSS group. Kaplan-Meier analysis showed a statistically significant difference of MACCE-free survival between the three groups (log-rank test, P  <   0.001). The estimated MACCE-free survival rate at 1 year was 98.1% [standard error (SE): 1.6] for the rSS low , 95.5% (SE: 1.9) for the rSS mid , and 90.5% (SE: 1.3) for the rSS high group, respectively. After multivariable adjustment, the rSS high group was independently associated with a higher incidence of MACCE at 1 year (hazard ratio 1.92, 95% confidence interval 1.21-3.23) compared to the rSS low group.
  
  
  
  These unanticipated findings suggest that a residual SS may be a useful tool for risk stratification of patients undergoing isolated first-time CABG. Our study may set the stage for further investigations addressing this important clinical question.
authors.affiliation: Department of Cardiac Surgery, Ospedale Sant'Andrea, Rome, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Melina
authors.affiliation: Department of Cardiac Surgery, Ospedale Sant'Andrea, Rome, Italy.
authors.forename: Emiliano
authors.initials: E
authors.lastname: Angeloni
authors.affiliation: Department of Cardiac Surgery, Ospedale Sant'Andrea, Rome, Italy.
authors.forename: Simone
authors.initials: S
authors.lastname: Refice
authors.affiliation: Department of Cardiac Surgery, Ospedale Sant'Andrea, Rome, Italy.
authors.forename: Cristian
authors.initials: C
authors.lastname: Benegiamo
authors.affiliation: Department of Cardiac Surgery, Ospedale Sant'Andrea, Rome, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Lechiancole
authors.affiliation: Department of Cardiac Surgery, Ospedale Sant'Andrea, Rome, Italy.
authors.forename: Maria
authors.initials: M
authors.lastname: Matteucci
authors.affiliation: Department of Cardiac Surgery, Ospedale Sant'Andrea, Rome, Italy.
authors.forename: Antonino
authors.initials: A
authors.lastname: Roscitano
authors.affiliation: Department of Cardiac Surgery, Ospedale Sant'Andrea, Rome, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Bianchini
authors.affiliation: Department of Cardiac Surgery, Ospedale Sant'Andrea, Rome, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Capuano
authors.affiliation: Department of Cardiac Surgery, Ospedale Sant'Andrea, Rome, Italy.
authors.forename: Cosimo
authors.initials: C
authors.lastname: Comito
authors.affiliation: Department of Cardiac Surgery, Ospedale Sant'Andrea, Rome, Italy.
authors.forename: Pietro
authors.initials: P
authors.lastname: Spitaleri
authors.affiliation: Department of Cardiac Surgery, Ospedale Sant'Andrea, Rome, Italy.
authors.forename: Euclide
authors.initials: E
authors.lastname: Tonelli
authors.affiliation: Catheterization Laboratory, Ospedale San Filippo Neri, Rome, Italy.
authors.forename: Giulio
authors.initials: G
authors.lastname: Speciale
authors.affiliation: Catheterization Laboratory, Ospedale San Filippo Neri, Rome, Italy.
authors.forename: Christian
authors.initials: C
authors.lastname: Pristipino
authors.affiliation: Department of Cardiology, Ospedale San Pietro Fatebenefratelli, Rome, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Monti
authors.affiliation: Department of Cardiology, Ospedale San Pietro Fatebenefratelli, Rome, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Serdoz
authors.affiliation: Center for Molecular Cardiology, University of Zurich, Zurich, Switzerland.
authors.forename: Francesco
authors.initials: F
authors.lastname: Paneni
authors.affiliation: Department of Cardiac Surgery, Ospedale Sant'Andrea, Rome, Italy.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Sinatra
mesh_terms: D000368:Aged; D001026:Coronary Artery Bypass / Q000009:adverse effects* / Q000379:methods; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D011182:Postoperative Care / Q000379:methods; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods; D012720:Severity of Illness Index; D016896:Treatment Outcome
keywords: Coronary artery bypass grafting; Outcomes; SYNTAX