Background: The double-chambered right ventricle (DCRV) is increasingly recognized as a distinct obstruction entity. The nature of the obstruction is not well defined.
Methods: Patients with DCRV were prospectively studied during the last 4 years according to the following criteria: 1) pressure gradient by echo Doppler and cardiac catheterization within the right ventricle; 2) angiographic demonstration, and 3) surgical confirmation.
Results: From March 1997 to March 2001, 10 new cases were included. Age ranged from 2 to 14 years (mean 9.5 +/- 4.4 years), weight ranged from 9.9 to 75 kg (mean 23 +/- 13.6 kg), and height from 0.85 to 1.48 m (mean 114 +/- 19 cm). Systolic gradient by echo Doppler ranged from 20 to 135 mmHg (mean 86 +/- 44 mmHg) and by cardiac catheterization, 18 to 130 mmHg (mean 78 +/- 35 mmHg). In terms of angiographic findings, in six patients the right ventriculogram showed an oblique and low obstruction; in four patients the obstruction was high and horizontal. With regard to surgical findings, angiographic findings were confirmed by the surgeon except in one patient, in whom both types of obstruction were present. No mortality was observed. With follow-up 4 to 40 months after surgery (mean 24 +/- 15 months), 8 of 10 patients were evaluated; all corresponded to class I NYHA. Systolic gradient by echo Doppler ranged from 0 to 11 mmHg (mean 4 +/- 6 mmHg).
Conclusions: DCRV IS PRODUCED BY THE FOLLOWING THREE TYPES OF MUSCULAR OBSTRUCTIONS: low and oblique obstruction; high and horizontal obstruction, and mixed obstruction. Mid-term surgical results are satisfactory.