Article

Exercise hemodynamics of bovine versus porcine bioprostheses: A prospective randomized comparison of the Mosaic and Perimount aortic valves

Department of Cardiovascular Surgery, German Heart Center Munich, Lazarettstrasse 36, 80636 Munich, Germany.
Journal of Thoracic and Cardiovascular Surgery (Impact Factor: 3.99). 06/2005; 129(5):1056-63. DOI: 10.1016/j.jtcvs.2004.08.028
Source: PubMed

ABSTRACT This prospective randomized study compares a porcine with a bovine bioprosthesis in the aortic position with regard to hemodynamic performance during exercise.
Between August of 2000 and December of 2002, 136 patients underwent aortic valve replacement with the porcine Medtronic Mosaic (n = 66) or the bovine Carpentier-Edwards Perimount (n = 70) bioprosthesis. Transthoracic echocardiography was performed to assess hemodynamic and dimensional data preoperatively and 10 months postoperatively; the latter follow-up included stress echocardiography with treadmill exercise.
At rest and during exercise (25 and 50 W), there was a significant difference in mean pressure gradient between the bovine and the porcine valves with labeled sizes 21 and 23, with superiority of the Perimount prosthesis. There was no difference in effective orifice area and incidence of patient-prosthesis mismatch among all sizes. The left ventricular mass index decreased significantly within 10 months postoperatively in the size 23 bovine group and the size 25 porcine group.
Our data show a significant superiority of pressure gradients for the bovine bioprosthesis, especially with small valve sizes, when compared with the porcine device, which is more distinctive during exercise.

Full-text

Available from: R. Bauernschmitt, May 23, 2014
1 Follower
 · 
129 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: OBJECTIVES: Small-sized aortic bioprostheses may cause high postoperative gradients. In clinical practice, it is difficult to compare bio-prostheses from different manufactures, owing to the discrepancy between the true size and the nominal size of the prosthesis and the inter-patient variability in aortic root characteristics. In vitro studies provide accurate data, and using a system in which it is possible to implant bioprostheses in a true aortic root should enable a fair comparison to be made. The present study compared the four most widely used pericardial stented bioprostheses from different manufacturers surgically implanted in small annulus, to detect any differences in their fluidodynamic performance. METHODS: The four types of bioprostheses, each implanted in a randomized sequence in eight porcine aortic roots, with a native annulus of 2.1 cm, were tested in a mock loop at 65 ml of stroke volume by calculating hydrodynamic parameters, namely mean pressure drop and effective orifice area, performance index, valve resistance and % of energy loss. The prostheses that fitted the aortic root after sizing were as follows: a Magna Ease 21, a Trifecta 21, a Soprano-Armonia 20 and a Mitroflow 23. RESULTS: Effective orifice areas were 1.57 ± 0.2, 1.77 ± 0.2, 2.3 ± 0.3 and 1.75 ± 0.2 cm 2 (P < 0.001) for Magna Ease, Mitroflow, Trifecta and Soprano-Armonia, respectively. The mean gradients were 13.2 ± 3, 10.2 ± 3, 6.1 ± 2 and 9.6 ± 2 mmHg (P < 0.001) for Magna Ease, Mitroflow, Trifecta and Soprano-Armonia, respectively. The performance indices were 0.50 ± 0.06, 0.63 ± 0.08, 0.89 ± 0.13 and 0.56 ± 0.07 (P < 0.001) for Magna Ease, Mitroflow, Trifecta and Soprano-Armonia, respectively. The valve resistance, expressed in (dyn*s/cm 5), was 69 ± 16, 55 ± 13, 33 ± 10 and 51 ± 11 (P < 0.001) for Magna Ease, Mitroflow, Trifecta and Soprano-Armonia, respectively. The percent of energy loss was 13.5 ± 0.5, 10.7 ± 2.5, 6.6 ± 1.6, 10.9 ± 1.8 (P < 0.001) for Magna Ease, Mitroflow, Trifecta and Soprano-Armonia, respectively. CONCLUSION: Our study combined the fluidodynamic reproducibility of the in vitro study with, by using porcine aortic roots, the specificity of surgery. The results confirmed that bioprostheses are inherently obstructive compared with the native aortic valve and showed that bio-prostheses with the pericardium outside the stent are more efficient.
    European Journal of Cardio-Thoracic Surgery 11/2014; DOI:10.1093/ejcts/ezu446 · 2.81 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background and Aim. While aortic valve replacement for aortic stenosis can be performed safely in elderly patients, there is a need for hemodynamic and quality of life evaluation to determine the value of aortic valve replacement in older patients who may have age-related activity limitation. Materials and Methods. We conducted a prospective evaluation of patients who underwent aortic valve replacement for aortic stenosis with the Hancock II porcine bioprosthesis. All patients underwent transthoracic echocardiography (TTE) and completed the RAND 36-Item Health Survey (SF-36) preoperatively and six months postoperatively. Results. From 2004 to 2007, 33 patients were enrolled with an average age of 75.3 ± 5.3 years (24 men and 9 women). Preoperatively, 27/33 (82%) were New York Heart Association (NYHA) Functional Classification 3, and postoperatively 27/33 (82%) were NYHA Functional Classification 1. Patients had a mean predicted maximum V O2 (mL/kg/min) of 19.5 ± 4.3 and an actual max V O2 of 15.5 ± 3.9, which was 80% of the predicted V O2 . Patients were found to have significant improvements (P ≤ 0.01) in six of the nine SF-36 health parameters. Conclusions. In our sample of elderly patients with aortic stenosis, replacing the aortic valve with a Hancock II bioprosthesis resulted in improved hemodynamics and quality of life.
    12/2014; 2014:151282. DOI:10.1155/2014/151282
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Data comparing the haemodynamic performance of stented pericardial and porcine aortic valves are conflicting. Hence, we performed a systematic review and meta-analysis comparing the early haemodynamic parameters of stented pericardial and porcine valves in patients undergoing isolated aortic valve replacement. Medline, EMBASE and Web of Science were queried for English language original publications from 2000 to 2013. Studies comparing porcine (PoV) and pericardial (PeV) with regard to their haemodynamic parameters were included in this review. Continuous data were pooled using the mean difference (MD) or the standardized mean difference (SMD). A random-effect inverse weighted analysis was conducted; a P-value <0.05 is considered statistically significant. Results are presented with 95% confidence intervals. Thirteen studies (1265 PeV patients and 871 PoV patients) were included in this analysis. The pooled transvalvular mean gradient was lower for PeV [MD -4.6 (-6.45 to -2.77) mmHg; P < 0.01]. Limiting this analysis to small valves (19 and 21 mm; eight studies; 714 patients) revealed that the PeV gradients were significantly lower [MD -4.5 (-5.7 to -3.2); P = 0.001]. The corresponding effective orifice area of PeV was significantly larger than PoV [SMD 0.42 (0.15-0.69); P < 0.01]. A sensitivity analysis comprising only randomized controlled trials did not significantly alter results. When compared with porcine valves, stented pericardial aortic valves have lower mean transvalvular gradients early after implant. Even pericardial valves in smaller sizes (19 and 21 mm) have a better haemodynamic profile when compared with their counterparts.
    European journal of cardio-thoracic surgery: official journal of the European Association for Cardio-thoracic Surgery 08/2014; DOI:10.1093/ejcts/ezu272 · 2.81 Impact Factor