Key result
A neutrophil surface area of ≥2% of the total valve tissue surface was highly predictive (90%) and specific (98%) for infective endocarditis in patients with mechanical valves.
Why the study?
Does quantitative histological examination differentiate infective endocarditis from noninfectious valve processes in patients with mechanical cardiac valves?
Observational (n=90)
Does quantitative histological examination differentiate infective endocarditis from noninfectious valve processes in patients with mechanical cardiac valves?
Neutrophil-rich inflammation (≥2% surface area) and extensive neovascularization can histologically define active endocarditis in mechanical valves when microorganisms or vegetations are absent.
May aid endocarditis diagnosis on explanted mechanical valves without organisms; hypothesis-generating and requires prospective validation before practice change.
BACKGROUND: Histological demonstration of microorganisms, vegetations, or active endocarditis in cardiac valve tissue is included in the Duke criteria and is considered to be a criterion of confirmed infective endocarditis. However, the histological features that characterize infective endocarditis are not accurately defined at the qualitative and quantitative levels. METHODS: Pathologic analysis of tissue adjoining mechanical cardiac valves was undertaken retrospectively for 21 patients who underwent surgical removal of a mechanical valve because of suspected infective endocarditis and 69 patients who underwent surgical removal of a mechanical valve because of noninfectious dysfunction. To better define the histological criteria for infective endocarditis, we used quantitative image analysis to compare these 2 groups of patients with respect to valvular fibrosis, calcifications, vegetations, patterns of inflammation, and vascularization. RESULTS: Histologically, infective endocarditis in patients with mechanical valves was characterized by the demonstration of microorganisms, vegetations, and significant neutrophil-rich inflammatory infiltrates with extensive neovascularization. In contrast, valve tissue specimens from patients with mechanical valves that were removed because of noninfectious complications showed significant rates of extensive fibrosis and, when present, inflammatory infiltrates that were mainly composed of macrophages and lymphocytes. A neutrophil surface area with a cutoff value of > or =2% of the total valve tissue surface is highly predictive of (90%) and specific for (98%) infective endocarditis. CONCLUSIONS: When no microorganisms are detected and vegetations are lacking in tissue adjacent to a mechanical valve, neutrophil-rich inflammation and extensive neovascularization might better histologically define the term "active endocarditis" in the Duke criteria. This definition would allow differentiation between infective endocarditis and inflammatory noninfectious valve processes in patients with mechanical cardiac valves.
No takes yet. Share an insight, caveat, or question.
Lépidi et al. (2005) conducted an observational in Mechanical heart valve infective endocarditis (n=90). Suspected infective endocarditis vs. Noninfectious valve dysfunction was evaluated on Histological features characterizing infective endocarditis (valvular fibrosis, calcifications, vegetations, patterns of inflammation, and vascularization). A neutrophil surface area of ≥2% of the total valve tissue surface was highly predictive (90%) and specific (98%) for infective endocarditis in patients with mechanical valves.
Synapse has enriched 3 closely related papers on similar clinical questions. Consider them for comparative context: