Association of Vegetation Size With Valve Destruction, Embolism and Mortality

The mortality of patients with infective endocarditis (IE) is high. The management of patients with large vegetations is controversial. This study sought to investigate the association of vegetation size on outcomes including valve destruction, embolism and mortality.

One hundred and forty-two (142) patients with definite IE and transoesophageal echocardiography (TEE) imaging available for analysis were identified and data retrospectively reviewed. Vegetation length, width and area were measured. Severe valve destruction was defined as the composite of one or more of severe valve regurgitation, abscess, pseudoaneurysm, perforation or fistula. Associations with 6-month mortality were identified by Cox regression analysis. Eighty (80) (56.3%) patients had evidence of valve destruction on TEE. Vegetation length ≥10 mm and vegetation area ≥50 mm² were significantly associated with increased risk of valve destruction, (both odds ratio OR 1.21, p=0.03 and p=0.02 respectively). Thirty-nine (39) (72.2%) patients who had an embolic event, did so prior initiation of antibiotics. Six (6)-month mortality was 18.3%. In the surgically managed group, vegetation size was not associated with mortality. In the medically managed group, vegetation area (mm²) was associated with increased mortality (HR 1.01, p<0.01) along with age (HR 1.06, p=0.03).

Vegetation length ≥10 mm or area ≥50 mm² are associated with increased risk of valve destruction. Vegetation size may also predict mortality in medically managed but not surgically managed patients with IE. Further studies to evaluate whether surgery in patients with large vegetation size improves outcomes is warranted.