Definitions of echocardiographic phenomena
  1. Asymptomatic masses on endocardial leads (AMEL) characterized by homogeneous echogenicity, smooth contour and varying degrees of organization. AMEL include components of connective tissue (accretions), clots, masses resembling vegetations (so-called vegetation-like masses). Vegetation-like masses may be the remnant vegetations after antibiotic treatment or (less probable) organized fibrotic thrombi [18].
  2. Hyperechoic segmental thickening of the leads defined as connective tissue overgrowth (undergoing fibrosis, mineralization, crystallization and even ossification) [18[.
  3. Bacterial vegetations: multishaped, mobile masses of inhomogeneous echogenicity attached to the leads or/and to the neighboring anatomic structures, most frequently tricuspid leaflets. They were found only if they were accompanied by signs of a general infection. Sometimes coexisting with AMEL (vegetation-like masses) [18].
  4. Accretion – immobile fibrous connective tissue sheath around the lead causing adherence to the endocardium and vessel walls and producing images similar to segmental lead thickening but moving along with the cardiac wall [18].
  5. Excessive lead loops - result of too weak fixation of the lead during implantation or lead fracture with break of insulation in the subclavian region [18].
  6. Cardiac wall perforation by the lead: visualization of the lead tip outside the heart contour, sometimes with fluid in the pericardial sac; placement of the lead tip close to the border of the pericardium is referred to as penetration [18].