paravalvular

Paravalvular describes processes or structures located around a heart valve prosthesis or valve annulus rather than within the valvular orifice. In medical reporting, the term most often appears in relation to paravalvular leak, a type of regurgitation where blood flows around a prosthetic valve rather than through its central opening.

Paravalvular leakage most commonly occurs after implantation of prosthetic heart valves, including surgical aortic or mitral valve replacements and transcatheter valves such as TAVR/TAVI. Risk factors include annular calcification, prosthesis malposition or underexpansion, residual tissue defects in the annulus, and, less commonly, endocarditis or abscess formation.

The mechanism involves incomplete apposition between the prosthetic ring or frame and the native annulus, creating a channel for blood to leak during systole or diastole depending on valve position. The clinical presentation ranges from no symptoms to progressive heart failure or hemolytic anemia, particularly with moderate to severe regurgitation.

Diagnosis relies on echocardiography, with transthoracic and transesophageal studies used to visualize the leak, estimate its severity, and characterize its location. Three-dimensional echo and, when needed, computed tomography can aid planning for intervention.

Management is individualized. Mild paravalvular leaks may be monitored with medical therapy; moderate to severe leaks causing symptoms or hemolysis may require percutaneous closure using occluder devices or, less commonly, surgical repair or valve re-intervention.

Prognosis depends on leak severity and hemodynamic impact; timely diagnosis and appropriate treatment improve outcomes.