Rest and exercise performance of pericardial vs. porcine bioprostheses

Objectives: To evaluate the potential hemodynamic superiority of bovine versus porcine biprostheses, we studied the hemodynamic performance of Edwards Perimount (bovine) and Medtronic Mosaic (porcine) bioprostheses in aortic position in a prospective randomized trial.

Material and Methods: Between August 2000 and September 2002, 94 Patients underwent aortic valve replacement receiving either Perimount (n=46, mean age 75.0 years, 45.6% males) or Mosaic (n=48, mean age 75.2 years, 48% males) bioprosthesis. Transthoracic echocardiography at rest and during exercise was performed 10 months postoperatively.

Results: Operative mortality, i.e. death within 30 days postoperative, was 2.0% in the Mosaic and 2.1% in the Perimount group; late mortality 2.0% for Mosaic and 6.5% for Perimount (n.s.). Echocardiography data at rest and during stress are shown in the table.

=significant in t-test with p<005
Size	MPG at rest (mmHg)		MPG at 25 Watt (mmHg)		MPG at 50 Watt (mmHg)
	Mosaic	Perimount	Mosaic	Perimount	Mosaic	Perimount
19	n=2; 26.2±8.0	n=2; 17.9±3.7	n=2; 28.4±8.9	n=3; 20.7±4.4	n=1; 18.8	n=2; 26.4±2.4
21	n=13; 14.9±4.5	n=15; 11.2±3.5	n=13; 19.4±6.4	n=15; 12.5±1.9	n=12; 22.5±6.0	n=13; 15.4±2.2
	t-test:	p=0.021*	t-test:	p=0.001*	t-test:	p=0.001*
23	n=23; 13.8±4.4	n=23; 10.9±4.3	n=23; 17.1±4.7	n=23; 13.2±3.5	n=18; 17.0±3.6	n=18; 17.0±3.6
	t-test:	p=0.030*	t-test:	p=0.003*	t-test:	p=0.001*
25	n=10; 13.7±4.0	n=5; 10.6±2.1	n=10; 17.1±5.3	n=5; 12.9±2.9	n=10; 19.6±6.0	n=5; 13.7±3.8
	t-test:	p=0.130	t-test:	p=0.132	t-test:	p=0.610

Conclusions: Our data show a significant hemodynamic superiority for the bovine bioprosthesis especially in small valve sizes (19–23mm) when compared to the porcine device, which is even more distinctive during mild exercise.