Exercise hemodynamic performance of the pulmonary autograft following the Ross procedure

Background and aims of the study: The Ross procedure, in which the aortic v alve is replaced with the patient's own pulmonary valve (pulmonary autograf t), is considered an excellent alternative for younger patients requiring e lective aortic valve replacement. Although resting pulmonary autograft hemo dynamics are excellent, exercise hemodynamic data are lacking. The study ai m was to measure the hemodynamic performance of the pulmonary autograft wit h exercise Doppler echocardiography (DE). Methods: Twenty-four Ross procedure patients (20 males, four females; mean age 46 +/- 11 years) were studied at 25 +/- 14 months after aortic valve re placement with a pulmonary autograft. Patients had baseline supine DE to me asure the maximum velocity (V-max), and the peak and mean pressure gradient across the pulmonary autograft. Effective orifice area was calculated from the continuity equation and indexed to body surface area (EOAi). Patients then underwent symptom-limited upright bicycle exercise with supine DE repe ated immediately on stopping exercise. For comparison, 10 normal controls ( age 41 +/- 10 years) and five mechanical aortic valve patients (mean age 55 +/- 10 years) were studied. Results: At rest: Ross procedure patients had similar V-max (1.2 +/- 0.2 m/ s), peak gradient (6 +/- 2 mmHg), mean gradient (4 +/- 1 mmHg) and EOAi (1. 7 +/- 0.4 cm(2)/m(2)) to those of normal controls. Mechanical-valve patient s had significantly higher V-max (2.5 +/- 0.2 m/s, p <0.001), peak gradient (25 +/- 4 mmHg, p <0.001) and mean gradient (14 +/- 3 mmHg, p <0.001) than Ross patients and normal controls. At exercise: Ross procedure patients ha d similar V-max (1.8 +/- 0.4 m/s versus 2.1 +/- 0.2, p = NS), peak gradient (14 +/- 6 mmHg versus 17 +/- 4,p = NS) and mean gradient (8 +/- 4 mmHg ver sus 10 +/- 2, p = NS) to normal controls, with no significant change in EOA i. Mechanical-valve patients had significantly higher V-max (3.4 +/- 0.3, p <0.001), peak gradient (48 +/- 7 mmHg, p <0.001) and mean gradient (30 +/- 5 mmHg, p <0.001) than Ross patients and normal controls. Conclusions: Aortic valve replacement using the Ross procedure provides exc ellent hemodynamic results at rest and on exercise, with DE parameters indi stinguishable from those of normal controls. This study provides further su pport for the use of the Ross procedure as a preferred method of aortic val ve replacement in younger patients.