I read with interest the article by Hildick-Smith and Shapiro [1] on balloon mitral valvuloplasty employing double transseptal puncture. In four patients with mechanical aortic prostheses which could not be safely crossed by retrograde arterial catheterization, the authors used double transseptal punctures to assess simultaneous left atrial and left ventricular pressures.
As in double balloon mitral valvuloplasty via a single transseptal puncture [2], this same technique can be applied to patients with rheumatic heart disease and mechanical aortic valve replacement who develop subsequent mitral stenosis. Use of two balloon catheters through a single transseptal puncture can be accomplished by introducing a Cournand catheter over the guide wire into the left atrium through the previously created small atrial septal puncture and passing another J-tip exchange guide wire through the Cournand catheter into the left atrium and then the left ventricle [3]. In 25 patients using this technique, Loya and Sharma [3] found no evidence of any left to right interatrial shunt.
Use of two balloon catheters through a single transseptal puncture has also been described by Palacios et al. [4].
They introduced the second exchange guide wire through the same transseptal puncture parallel to the first wire through a special double-lumen sheath. They found the interatrial communication created by the double-lumen sheath to be not hemodynamically significant. Furthermore, in 4 of their 35 patients (11%) with a small left-to-right shunt demonstrated immediately after balloon valvuloplasty, the shunt could not be demonstrated 24 hours later.