A commissurotomy is a procedure used to widen the opening of a heart valve that has become narrowed (stenotic) due to fusion of the valve leaflets along their natural joining points (commissures). The commissures are the points where adjacent valve leaflets meet at the edges of the valve orifice; in conditions such as rheumatic mitral stenosis, these edges fuse together, reducing the effective valve opening.
Commissurotomy separates the fused leaflets to widen the valve opening and improve forward blood flow. This can be achieved surgically (open commissurotomy under direct vision during open heart surgery) or via a catheter-based technique (balloon commissurotomy or balloon valvuloplasty, in which a balloon is inflated across the valve to mechanically separate the fused leaflets from within). The catheter-based approach is less invasive and has become the preferred technique where valve anatomy is suitable.
Mitral commissurotomy is most commonly performed for rheumatic mitral stenosis. Results are durable in patients with pliable, non-calcified valves; in those with heavily calcified or distorted valves, balloon commissurotomy is less effective and surgical valve repair or replacement may be required. Commissurotomy of the pulmonary valve can also be performed for pulmonary stenosis.
Commissurotomy should be distinguished from valve replacement, as it preserves the native valve and avoids the need for anticoagulation. It is specifically applicable to stenotic valves with fused commissures and cannot address valve regurgitation (leaking).
« Back to Glossary Index