Table 2

Differential diagnosis of drug-induced valvular heart disease (DIVHD): key features of distinct causes of valvular heart disease that might resemble DIVHD

FeaturesDIVHDRheumatic VHDPrimary Calcific VHDLibman-Sacks endocarditis30
Mechanism5-HT2B agonistMicrobial agents as triggerMultifactorial atherosclerosis-likeAntiphospholipid Syndrome-deposition immune complexes
AgeYoung and old depending on type drugYoungerOlderYounger and middle aged (women)
LocalisationLeft > rightLeft > rightLeftLeft ≫ right
Valvular thickeningYes ++(+)Yes +++Yes +Yes++, but also valvular masses
HistopathologyMyxoid plaques on the valve with conserved architectureNeovascularisation, inflammation and calcificationPredominant annular or valvular body leaflets calcificationsDiffuse thickening ± sterile fibrofibrinous vegetations, sometimes small calcifications
CalcificationNoYes +Yes ++Sometimes
Commissural fusionNoYes++ (MV >AV)Yes + (AV >MV)Rare (MV)
Restrictive motion and Increased tentingYes ++(+)Yes +++Yes +Yes+ if thickening is predominant feature
Functional effect (stenosis/regurgitation)RegurgitationStenosis and regurgitationStenosis and regurgitationRegurgitation (stenosis); systemic embolisation (mass)
Subvalvular apparatusThickened and shortenedThickened, calcified and shortenedLess affectedNot affected
  • In some cases different diseases might be present in the same patient complicating the diagnosis.