Early experience with the new Masters series of St. Jude Medical heart valve: in vivo hemodynamic and clinical results in patients with narrowed aortic annulus.

BACKGROUND AND AIMS OF THE STUDY

Aortic valve replacement in the small aortic root results in a heart-prosthesis mismatch in a significant number of patients. The new Masters series of St. Jude Medical (SJM) valves represents the company's most recent innovation, combining the beneficial Hemodynamic Plus (HP) characteristics with rotatability. Thus, this valve allows for a larger valve orifice area with an equivalent tissue annulus diameter and reduces the potential interferences of subannular tissue with leaflet mobility.

METHODS

We compared prospectively the hemodynamic characteristics and the early clinical results in four groups of 25 patients each who received either the 21 Masters-HP, the 21 Standard, the 21 HP or the 23 Standard SJM valves. Patients were selected from our database and matched rigorously for age, gender, body surface area, NYHA functional class, underlying lesion, native valve opening area and left ventricular function, as well as preoperative peak and mean valve gradients. Postoperative evaluation included clinical examination and echocardiographic studies before hospital discharge and at six months.

RESULTS

Short-term clinical follow up was marked by a complete absence of valve-related complications in all groups. Doppler-derived mean and maximal pressure gradients were significantly lower in the 21 HP (8.7 +/- 3.1 mmHg and 15.1 +/- 4.0 mmHg, respectively) and 21 Masters-HP groups (8.9 +/- 2.6 mm +/- Hg and 14.5 +/- 3.8 mmHg) than those in the 21 Standard group (15.1 +/- 3.2 mmHg and 22.5 +/- 6.1 mmHg; p = 0.002 and p = 0.004, respectively). These results confirm that the superior hemodynamic performance of the HP series is maintained in the Masters-HP valve, despite the introduction of a new cuff design allowing rotatability. Pressure gradients did not differ significantly between the 21 HP, the 21 Masters-HP and the 23 Standard groups.

CONCLUSIONS

The hemodynamic performance of the 21 Masters-HP SJM valve corresponds closely with that of the 21 HP and 23 Standard valves and is substantially better than that of the 21 Standard valve. The Masters-HP valve will continue to reduce cardiac-prosthesis mismatch in normal-sized patients with a narrowed aortic root; its performance index is equal to that of the 21 HP valve and significantly higher than that of the 21 Standard valves. The valve will also further reduce the need for aortic annulus enlargement.