The NOVA score: a proposal to reduce the need for transesophageal echocardiography in patients with enterococcal bacteremia

Clin Infect Dis. 2015 Feb 15;60(4):528-35. doi: 10.1093/cid/ciu872. Epub 2014 Nov 7.


Background: Frequency of enterococcal bloodstream infection (E-BSI) is increasing, and the number of episodes complicated by infective endocarditis (IE) varies. Performing transesophageal echocardiography (TEE) in all patients with E-BSI is costly and time-consuming. Our objectives were to identify patients with E-BSI who are at very low risk of enterococcal IE (and therefore do not require TEE) and to compare the outcome of E-BSI in patients with/without IE.

Methods: Between September 2003 and October 2012, we performed a prospective cohort study (all patients with E-BSI) and a case-control study (patients with/without enterococcal IE) in our center.

Results: We detected 1515 patients with E-BSI and 65 with enterococcal IE (4.29% of all episodes of E-BSI, 16.7% of patients with E-BSI who underwent transthoracic echocardiography, and 35.5% of all patients with E-BSI who underwent TEE). We developed a bedside predictive score for enterococcal IE-Number of positive blood cultures, Origin of the bacteremia, previous Valve disease, Auscultation of heart murmur (NOVA) score-based on the following variables: Number of positive blood cultures (3/3 blood cultures or the majority if more than 3), 5 points; unknown Origin of bacteremia, 4 points; prior heart Valve disease, 2 points; Auscultation of a heart murmur, 1 point (receiver operating characteristic = 0.83). The best cutoff corresponded to a score ≥4 (sensitivity, 100%; specificity, 29%). A score <4 points suggested a very low risk for enterococcal IE and that TEE could be obviated.

Conclusions: Enterococcal IE may be more frequent than generally thought. Depending on local prevalence of endocarditis, application of the NOVA score may safely obviate echocardiography in 14%-27% of patients with E-BSI.

Keywords: Enterococcus spp.; bacteremia; endocarditis.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Bacteremia / complications*
  • Blood / microbiology
  • Case-Control Studies
  • Cohort Studies
  • Echocardiography, Transesophageal* / statistics & numerical data
  • Endocarditis, Bacterial / diagnosis*
  • Endocarditis, Bacterial / diagnostic imaging
  • Endocarditis, Bacterial / epidemiology*
  • Enterococcus faecalis / isolation & purification*
  • Enterococcus* / isolation & purification
  • Female
  • Gram-Positive Bacterial Infections / diagnosis*
  • Gram-Positive Bacterial Infections / diagnostic imaging
  • Gram-Positive Bacterial Infections / epidemiology
  • Heart Murmurs
  • Heart Valve Diseases
  • Humans
  • Logistic Models
  • Male
  • Middle Aged
  • Prospective Studies
  • Risk Factors
  • Spain
  • Young Adult