Table 1:
Best Evidence papers
| Author, date, journal, country Study Type (level of evidence) | Patient group | Outcome | Key result | Comments |
|---|---|---|---|---|
| Rohmann (1992), Eur Heart J, Germany [2] Prospective cohort study (level 3) |
281 patients with IE. The prognostic value of ascertaining the site of vegetations evaluated |
Risk of embolic Risk of abscess Surgical Intervention Mortality Risk factors for embolism |
MV vs AV 25 vs 9.7% 0 vs 6% 5.5 vs 11% 0 vs 1.6% Vegetation size (VS) of >10 mm |
TOE assessed the clinical outcome Mean follow up of 14 months |
| Vilacosta (2002), J Am Coll Cardiol, Spain [3] Prospective cohort study (level 3) |
217 episodes of left-sided IE that were experienced among a cohort of 211 prospectively recruited patients | Increased risk of embolization with increasing VS The increased VS at follow-up showed a higher risk for embolization Risk factors for embolism |
RR 3.77, 95% CI 0.97 to 12.57;(P = 0.07) RR 2.64, 95% CI 0.98– 7.16; P = 0.02 VS of ≥10 mm) when the organism was staphylococcus (P = 0.04) |
TOE and TTE used in assessment Failure of antimicrobial treatment is assessed by increasing VS during therapy |
| Mugge (1989), J Am Coll Cardiol, Germany [4] Prospective cohort study (level 3) |
105 patients with active IE, disease-associated complications defined as severe heart failure (New York Heart Association class IV), embolic events and in-hospital death were correlated to the VS | The correlation of VS with endocarditis-associated complications with a vegetation diameter | Patients with a VS >10 mm had a significantly higher incidence of embolic events than did those with a VS ≤10 mm (22 of 47 vs 11of 58; (P < 0.01) | TOE and TTE used in assessment No correlation between VS and location of endocarditis or infective organism |
| Hecht (1992), Ann Intern Med, USA [5] Retrospective study (level 4) |
121 patients intravenous with IE. The presence of a right-sided valve vegetation assessed | Mortality rate | VS >20 mm vs ≤20 mm (33 VS 1.3%; P < 0.001) | RSIE assessed Observer blinded study No follow-up |
| Thuny (2005), Circ, France [6] Prospective cohort study (level 3) |
A multicentre study, including 384 consecutive patients (aged 57 ± 17 years) with definite IE using the Duke University criteria | Predictor of 1-year mortality | VS >15 mm (adjusted RR = 1.8; 95% CI, 1.10–2.82; P = 0.02) | TOE used in assessment Multicentre study No follow-up |
| Robbins, (1986), Am J Med [7] Retrospective study (level 4) |
This study evaluated the prognostic value of VS in 23 episodes of RSIE in 21 patients | Indication for surgery | No surgery for VS of <10 mm, while VS of ≥10 mm required surgery for persistent pyrexia (P < 0.05) | RSIE assessed |
| Nunes (2010), J Infect Dis, Brazil [8] Prospective cohort study (level 3) |
62 patients with IE during a 7-year period. The Cox proportional hazards model was used to identify predictive factors for death | The overall in-hospital mortality | VS >13 mm was the only independent predictor of in-hospital mortality (hazard ratio 1.05 per mm; 95% CI 1.003–1.110; P = 0.038) | TOE was used in assessment Prospective study No follow-up |
| Martin-Davilla (2005), Am Heart J, Spain [9] Retrospective study (level 4) |
493 cases of IE. VS was available in 111 cases | Variables associated with mortality | VS > cm (P = 0.014; OR 10.2; 95% CI 1.6–78.0) | RSIE No follow-up Not too sure about the role of early surgery |
| Wong (1983), Arch Intern Med, USA [10] Prospective cohort study (level 3) |
34 patients with clinical IE. Vegetations were identified in 16 patients (47%) by M-mode and in 27 patients (87%) by 2D echocardiography | Classification of VS 1 Small 2 Medium 3 Large Incidence of surgery |
<5 mm 5 mm–9 mm >10 mm >10 mm (44% vs 0%) |
Small sample size Advocated useful classification No follow-up Usefulness of different echocardiographic mode |
| Tischler (1997), J Am Soc Echocardiogr, USA [11] Meta-analysis (level 3) |
A meta-analysis of which identified by a computerized search of the key words IE and echocardiography A pooled odds ratio was calculated by using the Robins, Greenland, and Breslow estimate of variance |
The pooled odds ratio for increased risk of systemic embolization in the presence of a vegetation | VS >10 mm (10 studies, 738 patients) was 2.80 (95% CI 1.95–4.02; P < 0.01). The odds ratio of requiring valve-replacement surgery (7 studies, 549 patients) was 2.95 (95% CI 1.90–4.58; P < 0.01). The odds ratio of death (6 studies, 476 patients) was 1.55 (95% CI 0.92–2.60; P = 0.10) | Meta-analysis without homogeneity |
| Goldman (1995), Int J Cardiol, USA [12] Retrospective (level 4) |
74 patients with IE | VS of >1.8 cm2 | 100% specific but only 30% sensitive for predicting the development of a complication | The area of the vegetation calculated |
| Rohmann (1991), J Am Soc Echocardiogr, Germany [13] Prospective cohort study (level 3) |
83 patients with IE monitored for a mean of 74 weeks | Group A vs Group B VS Incidence of complications: Embolic events Perivalvular abscess formation Mortality Staphylococcus aureus Streptococcus viridans |
Increasing VS (8.2 ± 1.5–11.2 mm; P < 0.05) vs decreasing VS (8.3 ± 0.8 to 4.9 ± 0.8 mm P < 0.05) 45 vs 2%, P < 0.05 45 vs 17% P < 0.05 13 vs 2% P < 0.05 10 vs 0% P < 0.05 44 vs 11% P < 0.05) 33 vs 18% P < 0.05 |
TOE Prospective study Other complications also assessed VS used as a prognostication means |
| Di Salvo (2001), J Am Coll Cardiol, France [14] Retrospective study (level 4) |
178 consecutive patients with IE | Incidence of embolism | VS < 10 mm (60%, P < 0.001) Mobile vegetations (62%; P < 0.001) RSIE |
TOE was used. The incidence of EE compared with respect to other characteristics |
| Rohmann (1997), Clin Cardiol, Germany [15] Prospective cohort study (level 2) |
The effect of antibiotic regimes on VS in 183 patients with IE. The patients were followed for a mean of 76 weeks and had a minimum of two consecutive TOE | Treatment with different antibiotics with corresponding change in VS: 1 vancomycin 2 ampicillin 3 penicillin 4 penicillase-resistant drugs 5 cephalosporin |
45% reduction 19% reduction 5% reduction 15% increase 40% increase |
The patients were followed for a mean of 76 weeks TOE was used in assessment |
| Heinle (1994), Am J Cardiol, USA [16] Retrospective (level 3) |
41 patients with IE independently reviewed by 4 echocardiographers blinded to the clinical data. The vegetations were assessed for other characteristics | Incidence of embolic events | 50% EE in VS of >10 mm vs 42% VS of ≤10 mm | To determine inter-observer variability of echocardiographic characteristics of vegetations in patients with IE Prospective study |
| Leitman (2011), Eur J Echocardiogr, Israel [17] Retrospective study (level 4) |
146 patients with IE were identified Large vegetations (≥10 mm) occurred in 46 patients |
Risk of mortality The strongest independent predictor of mortality |
Older patients with large VS had increased risk of mortality 38% (P < 0.05) 1 MRSA IE (45%; P = 0.01) 2 staphylococcal IE with large VS in older patients (50%, P = 0.02) diabetes (25%, P < 0.02) |
The other factors for predicting mortality was also determined Results not explicit |
AV: aortic valve; EE: embolic event; IE: infective endocarditis; MRSA: methicilin resistant staphylococcus aureus; MV: mitral valve; RSIE: right-sided infective endocarditis; TOE: transoesophageal echocardiography; TTE: transthoracic echocardiography; VS: vegetation size.