One-year hemodynamic comparison of Perimount Magna with St Jude Epic aortic bioprostheses.

INTRODUCTION: Cardiac surgeons are using more bioprosthetic valves due to the ageing population as well as to improvements that have been made to these implants. We sought to compare the 1-year hemodynamics of two commercially available valves by echocardiographic parameters. MATERIAL AND METHODS: Retrospective review of our institutional database revealed 69 patients who received either Perimount Magna (n = 33) or St Jude Epic (n = 36) valves in the aortic position with no other valve surgery between June 2004 and March 2006. All patients received transthoracic echocardiography at 1 year. Comparisons between groups were made at baseline and at 1-year follow-up. In addition, a pairwise comparison was performed in each patient to determine the change in echocardiographic parameters between baseline and follow-up. RESULTS: Mean implanted valve size was similar (Magna 24.3 ±2.0 mm vs. Epic 24.1 ±2.2 mm). Pre- and intraoperative patient variables were similar between the two groups. There were lower peak and mean pressure gradients in the Magna group, both at discharge and one year after surgery. This correlated with a larger indexed effective orifice area (Magna 0.8 ±0.2 cm(2)/m(2) vs. Epic 0.67 ±0.2 cm(2)/m(2), p = 0.02). In spite of these findings, left ventricular mass regression was not different. CONCLUSIONS: These findings suggest that in a series with relatively low indexed effective orifice areas, the peak and mean gradients obtained were acceptable. More clinical follow-up of these patients is required to assess the true impact of prosthesis patient mismatch.

Postimplantation morphologic changes of glutaraldehyde-fixed porcine aortic roots and risk of aneurysm and rupture.

OBJECTIVE: Rupture of glutaraldehyde-fixed porcine aortic roots has been reported, but the mechanism and incidence of this complication is unknown. This study evaluates the clinical outcomes and the risk of dilation and rupture of porcine aortic roots after implantation. METHODS: Commercially available porcine aortic roots were used for aortic root replacement in 308 patients (Freestyle bioprosthesis [Medtronic, Minneapolis, Minn] in 251 patients and Toronto Root [St Jude Medical, St Paul, Minn] in 57 patients) whose mean age was 62 +/- 13 years. The main indication for aortic root replacement was dilation of the native aortic root. Clinical follow-up was complete at a mean of 5.3 +/- 2.5 years. Valve function and aortic root diameter were assessed by means of echocardiography. RESULTS: There were 10 (3.2%) operative and 39 (12.6%) late deaths. At 8 years, patients' survival was 79.0% +/- 3.1%, freedom from reoperation was 95.3% +/- 1.7%, and freedom from severe aortic insufficiency was 93.8% +/- 2.7%. The diameter of the aortic sinuses increased from 31.9 +/- 4.3 to 34.1 +/- 4.8 mm (P < .0001), and it exceeded 40 mm in 10% of the patients. Linear regression analysis revealed that the duration of follow-up (P < .0001) and the size of the valve implanted (P < .0001) were associated with risk of sinus dilation. There was only 1 early rupture of the noncoronary aortic sinus and 2 late aneurysms that required repeat operations. Histologic examination of explanted aneurysmal porcine roots revealed marked changes in the xenograft arterial wall, with abundant mononuclear cells suggestive of immunologic reaction. CONCLUSIONS: Mild dilation of porcine aortic roots after aortic root replacement is common, but aneurysm formation and rupture are rare during the first decade of follow-up. Annual surveillance with echocardiography is recommended.

Aortic valve replacement with Toronto SPV bioprosthesis: optimal patient survival but suboptimal valve durability.

OBJECTIVE: Our objective was to examine the clinical outcomes of aortic valve replacement with the Toronto SPV bioprosthesis at 12 years. METHODS: The Toronto SPV was used for aortic valve replacement in 357 patients from July 1991 to December 2004. There were 244 men and 113 women with a mean age of 65 +/- 10 years. Aortic stenosis was present in 79% of patients, coronary artery disease in 38%, and left ventricular ejection fraction less than 0.40 in 12%. Patients had an annual assessment of valve function using echocardiography. The mean duration of follow-up was 7.7 +/- 3.2 years. RESULTS: There were 2 operative and 79 late deaths, of which 13 were valve related and 25 heart related. Survival at 12 years was 64% +/- 4% and similar to that of the general population matched for age and sex. Forty-nine patients had echocardiographic evidence of bioprosthetic dysfunction. The freedom from structural valve degeneration at 12 years was 69% +/- 4% for all patients, 52% +/- 8% for patients less than 65 years of age, and 85% +/- 4% for patients 65 years of age or older (P = .002). Fifty patients had redo aortic valve replacement: 45 for structural valve degeneration and 5 for endocarditis. The freedom from redo aortic valve replacement at 12 years was 69% +/- 4%. Cusp tear with consequent aortic insufficiency was the most common cause of structural valve degeneration. At the latest follow-up contact, 226 (63%) patients were alive with the Toronto SPV valve in place, and 69% were in functional class I, 24% in class II, and 7% in class III. CONCLUSIONS: The Toronto SPV bioprosthesis has provided optimal patient survival and symptomatic improvement but suboptimal valve durability, particularly in patients less than 65 years of age. We now use of this valve mostly in older patients who have a small aortic annulus.

Aortic valve replacement with the Toronto SPV: long-term clinical and hemodynamic results.

OBJECTIVE: Long-term durability and hemodynamics of stentless valves are unknown. Therefore, this study was undertaken to evaluate long-term clinical and echocardiographic outcome after aortic valve replacement with the Toronto stentless porcine valve (SPV) bioprosthesis at our institution. METHODS: Between 1991 and 1998, the Toronto SPV was implanted in 255 patients (mean age, 63+/-11 years, range 22-83 years, 181 males and 74 females). Preoperative diagnoses were aortic stenosis (76%), aortic insufficiency (12%) and mixed lesion (12%). New York Heart Association class III and IV were present in 49% (126/255) of the patients preoperatively. Mean valve size implanted was 26.5+/-2.1mm and in addition 34% (86/255) of the patients had coronary artery bypass surgery. RESULTS: Early mortality was 0.8% (2/255). Actuarial survival at 7 years was 90+/-3%. At 7 years, the freedom from cardiac death was 98+/-2%; from valve-related death, 99+/-1%; from valve reoperation, 97+/-2%; from structural valve degeneration, 97+/-2%; from thromboembolism, 95+/-2%; and from endocarditis, 99+/-1%. At 7 years of follow-up, the transvalvular peak and mean pressure differences across the aortic valve measured with Doppler echocardiography was 9.6+/-5.1 and 3.6+/-2.0 mmHg, respectively. CONCLUSIONS: The Toronto SPV has provided excellent clinical and hemodynamic results up until 7 years of follow-up.