Pitfalls in bedside diagnosis of severe acute mitral regurgitation. Clinical and hemodynamic features

We describe five patients with severe acute mitral regurgitation in whom delay in diagnosis contributed to their fatal outcome. Either a soft systolic murmur was not heard or was misinterpreted, or hemodynamic confirmation by bedside right heart catheterization was unduly delayed. Pitfalls in recognition of hemodynamic patterns further postponed diagnosis and therapy. The diagnosis should be suspected when, in the proper setting, significant hemodynamic deterioration occurs, and is confirmed by bedside balloon flotation catheterization. Large V waves, characteristic of acute mitral regurgitation, may be overlooked unless one pays attention to the pulmonary artery systolic pressure tracing, which often has a triangular shape and may be double peaked; the V wave occurs later causing the second peak. Careful balloon inflation will demonstrate the large V waves. Timing with simultaneous ECG recordings allow this differentiation. Pulmonary hypertension with normal pulmonary vascular resistance is typical.