Early experience with the mosaic bioprosthesis: a new generation porcine valve

Implications of hydrodynamic testing to guide sizing of self-expanding transcatheter heart valves for valve-in-valve procedures

AIMS

The commonly used valve-in-valve (VIV) app recommends sizing based on dimensions of both the transcatheter heart valve (THV) and bioprosthetic surgical valve. The implications of hydrodynamic testing to guide VIV sizing are poorly understood. This bench study assessed the hydrodynamic performance of different sizes of self-expanding supra-annular THVs in three different surgical aortic bioprostheses at different implantation depths.

METHODS

A small versus medium ACURATE neo (ACn), and a 26 mm versus 29 mm Evolut R were assessed after VIV implantation in 25 mm Mitroflow, Mosaic, and Magna Ease aortic surgical bioprostheses, at three implantation depths (+2 mm, -2 mm, and -6 mm).

RESULTS

The medium-sized ACn had lower gradients compared to the small ACn when the THV was implanted high (+2 mm, or -2 mm). The 29 mm Evolut R had lower gradients compared to a 26 mm Evolut R for all implantation depths, except for a depth of -2 mm in the 25 mm Mitroflow. The medium ACn and 29 mm Evolut R had larger effective orifice areas compared to the small ACn and 26 mm Evolut R, respectively. Both Evolut R sizes had acceptable regurgitant fractions (<15%), while both ACn sizes were above the acceptable performance criteria (>15%), at all implantation depths.

CONCLUSIONS

Use of a larger self-expanding THV was associated with superior hydrodynamic performance if the THV was implanted high. Hydrodynamic testing can provide additional information to the VIV app to help guide VIV sizing.

Hemodynamic Performance and Outcomes of Mosaic Valve for Aortic Stenosis with Decreased Left Ventricular Function: Results from J-MOVE Study

We evaluated impact of a small-sized Mosaic porcine bioprosthesis on hemodynamic performance and outcomes in patients with aortic stenosis (AS) and low left ventricular ejection fraction (LVEF) in a Japan multicenter cohort. Of 1,202 patients enrolled, 105 (8.7%) who had LVEF < 50% and AS underwent aortic valve replacement (AVR). Fifty-two patients received Mosaic porcine bioprosthesis ≤ 21 mm (S-AVR), and 53 received a bioprosthesis ≥ 23 mm (L-AVR). The median follow-up period was 3.1 [1.2, 5.1] years. At 5 years, LVEF significantly improved from median 41.2 [33.8, 45.9]% to 64.2 [49.8, 72.5]% in S-AVR (p < 0.001) and from median 43.2 [37.3, 46.8]% to 61.2 [47.2, 68.0]% in L-AVR (p < 0.001). The left ventricular mass index significantly decreased from median 158.4 [122.2, 194.9] to 110.0 [83.6, 129.4] gm/m in S-AVR (p < 0.001) and from median 169.8 [132.2, 203.6] to 109.6 [101.8, 132.4] gm/m in L-AVR (p < 0.001). There were no significant differences between S-AVR and L-AVR groups regarding freedom from cardiac death (93.1 ± 3.9% vs. 96.2 ± 3.8%; p = 0.119) and valve-related death (97.6 ± 2.4% vs. 100.0 ± 0.0%; p = 0.953). Clinical outcomes and improved hemodynamic performance were similar in both groups.

St. Jude Medical Trifecta™ aortic valve perioperative performance in 200 patients

OBJECTIVES

The St. Jude Medical Trifecta aortic bioprosthesis (St. Jude Medical, Inc., St. Paul, MN, USA) is a new stented pericardial tissue heart valve. The aim of the study was to evaluate the clinical and haemodynamic performance of the Trifecta bioprosthesis in the early postoperative period.

METHODS

From July 2010 to September 2012, a total of 200 consecutive patients underwent aortic valve replacement with the Trifecta valve in our institution. All intraoperative and postoperative data were prospectively collected. Mean EuroSCORE II was 3.98%. Echocardiography was performed at discharge in all patients.

RESULTS

The mean age was 71.2 ± 7.7 (range 39-89 years). Extubation in the operating theatre was successfully performed in 96% of patients. Mean hospital stay was 8.5 days. The prosthesis sizes were 19 mm (n = 33), 21 mm (n = 81), 23 mm (n = 59), 25 mm (n = 23) and 27 mm (n = 4). Mean systolic pressure gradients ranged from 9.4 mmHg (size 19 valve) to 4.8 mmHg (size 27 valve). Mean effective orifice area (EOA) ranged from 1.61 cm(2) (size 19 valve) to 2.5 cm(2) (size 27 valve). Severe mismatch (<0.65 cm(2)/m(2)) did not occur in any patient. Of note, 99.5% of patients had mild or no aortic insufficiency at discharge. The early (30-day) mortality was 2.5% (n = 5).

CONCLUSIONS

The Trifecta valve offers good clinical results and excellent haemodynamic performance. Special care must be taken to avoid oversizing, which can lead to difficulty in implantation and can produce gradient increases due to an excess of prosthetic leaflet tissue.

Clinical and echocardiographic outcomes after implantation of the Trifecta aortic bioprosthesis: an initial single-centre experience

OBJECTIVES

The Trifecta valve (St. Jude Medical) was introduced into clinical practice as a tri-leaflet stented pericardial valve designed for supra-annular placement in the aortic position. The present study aims to evaluate the preliminary results with this new bioprosthesis.

METHODS

Seventy patients underwent aortic valve replacement (AVR) with the Trifecta valve between August 2010 and December 2011. Thirty-three patients were male and 37 were female (52.9%). Mean age was 74.65 ± 7.63 (range 47-90 years). Prevalent cause of AVR was aortic stenosis in 64 (91.43%) patients. The mean preoperative pressure gradient was 50 ± 17 (range 20-84 mmHg), and the mean aortic valve area was 0.77 ± 0.33. Five (7.14%) patients were operated on due to aortic valve endocarditis. One patient was operated on due to isolated, severe aortic insufficiency. All patients were in New York Heart Association functional class III or IV. Twenty-eight (40%) patients underwent concomitant procedures.

RESULTS

Concomitant procedures were coronary artery bypass grafting (n = 25), mitral valve replacement (n = 1), ablation of atrial fibrillation (n = 1) and septal myomectomy (n = 1). There were no intraoperative deaths. The 30-day in-hospital mortality was 2.85% (2 of 70). One late death occurred during the in-hospital stay due to a multiorgan failure on postoperative day 60. There were 2 (2.85%) perioperative strokes. Mean pressure gradient decreased significantly from a preoperative value of 50 ± 17 mmHg to an intraoperative gradient of 9 ± 4 mmHg (Table 3). The mean gradients were 14, 11, 11, 8 and 6 mmHg for the 19, 21, 23, 25 and 27 mm valve size, respectively. No prosthesis dislocation, endocarditis, valve thrombosis or relevant aortic regurgitation was observed at discharge.

CONCLUSIONS

The initial experience with the Trifecta valve bioprosthesis shows excellent outcomes with favourable early haemodynamics. Further studies with longer follow-up are needed to confirm those preliminary results.

Usefulness of phenprocoumon for the treatment of obstructing thrombus in bioprostheses in the aortic valve position

Bioprosthetic valve replacement is the treatment of choice in older patients with symptomatic severe aortic valve disease. Thrombosis of bioprosthetic valves has been considered a rare complication; however, in the presence of valvular obstruction, therapeutic consequences for the individual patient may be dramatic including repeat valve replacement or thrombolysis. We therefore evaluated oral anticoagulation with phenprocoumon as an alternative treatment for obstructive thrombosis of bioprosthetic valves. Six of 470 patients who had received a single stented bioprosthetic aortic valve from January 2007 through December 2008 at our hospital presented with obstructive bioprosthetic valve thrombosis within 14 months postoperatively. All 6 patients (1% of study population) had received a porcine valve (p = 0.1 vs pericardial), were hemodynamically stable, were in sinus rhythm, and were taking acetylsalicylic acid 100 mg/day. Echocardiography showed an increase in mean pressure gradient early postoperatively from 23.3 ± 4 to 57.0 ± 10 mm Hg (p <0.001). Five patients were started on phenprocoumon and followed for 114 ± 54 days, when mean pressure gradient had returned to 23.5 ± 6 mm Hg. No adverse events were observed during that period. One patient presenting with dyspnea and fever underwent emergency repeat valve replacement for suspected endocarditis, with histology showing long-term thrombosis of the explanted valve. In conclusion, oral anticoagulation with phenprocoumon represents a safe and effective treatment in clinically stable patients with obstructive thrombosis of bioprosthetic aortic valves, thus obviating repeat valve surgery or thrombolysis.

Diagnostic evaluation of left-sided prosthetic heart valve dysfunction

Prosthetic heart valve (PHV) dysfunction is a rare, but potentially life-threatening, complication. In clinical practice, PHV dysfunction poses a diagnostic dilemma. Echocardiography and fluoroscopy are the imaging techniques of choice and are routinely used in daily practice. However, these techniques sometimes fail to determine the specific cause of PHV dysfunction, which is crucial to the selection of the appropriate treatment strategy. Multidetector-row CT (MDCT) can be of additional value in diagnosing the specific cause of PHV dysfunction and provides valuable complimentary information for surgical planning in case of reoperation. Cardiac magnetic resonance imaging (CMR) has limited value in the evaluation of biological PHV dysfunction. In this Review, we discuss the use of established imaging modalities for the detection of left-sided mechanical and biological PHV dysfunction and discuss the complementary role of MDCT in this context.

Hemodynamic performance of the Medtronic Mosaic porcine bioprosthesis up to ten years

BACKGROUND

The Mosaic bioprosthesis (Medtronic, Minneapolis, MN) is a third-generation stented porcine bioprosthesis combining physiologic fixation and amino oleic acid antimineralization treatment to improve hemodynamic performance and durability. The findings of this single-center experience with this valve were evaluated to determine the clinical and hemodynamic performance.

METHODS

Between February 1994 and October 1999, we enrolled 255 patients with aortic valve replacement (AVR) with a mean age of 67 years (range, 23 to 82 years) and 47 patients with mitral valve replacement (MVR) with a mean age of 67 years (range, 41 to 84 years) in this post-United States Food and Drug Administration approval prospective and nonrandomized clinical trial. Patients were followed-up, including serial echocardiographic assessment, within 30 days, at 6 months, and annually thereafter. The cumulative follow-up was 1540 patient-years for AVR (mean, 6.1 years; maximum, 10 years) and 250 patient-years for MVR (mean, 5.4 years, maximum; 10 years).

RESULTS

Early mortality after AVR (<30 days) was 0.8%; late mortality per patient-year was 3.5%, including a valve-related/unexplained mortality of 1.1%. Early mortality after MVR (<30 days) was 0.0%; late mortality per patient-year was 2.8%, including a valve-related/unexplained mortality of 1.2%. Median postoperative gradient and effective orifice area for all valves after AVR were (early, n = 252; 5 years, n = 161; 9 years, n = 43) 13.7, 12.3, and 11.7 mm Hg and 1.9, 1.8, and 1.8 cm2 at early, 5 years, and 9 years, respectively. With MVR respective data were (early, n = 46; 5 years, n = 25; 7 years, n = 13) 4.6, 4.1, and 3.9 mm Hg and 1.8, 2.2, and 2.3 cm2. At 10 years, freedom from adverse events in the AVR group and MVR group was, respectively, thromboembolism, 86.6% +/- 6.6% and 86.3% +/- 9.8%; permanent neurologic event, 91.2% +/- 6.8% and 90.9% +/- 8.7%; valve thrombosis, 98.2% +/- 0.8% and 100%; structural valve deterioration, 87.1% +/- 6.7% and 100%.

CONCLUSIONS

Our midterm results demonstrate clinical safety and good performance of the Mosaic bioprosthesis. Continued follow-up will determine if this new design will provide increased durability.

Heart valve replacement: which valve for which patient?

The ideal heart valve substitute would show no deterioration or thrombogenicity, offer no resistance to blood flow, and be easy to implant. However, such a valve does not exist and we must accept compromises in some of these qualities based on our patients' needs. In selection of cardiac valve prosthesis, valve-related factors such as durability, thrombogenicity, and fluid dynamics should be carefully matched to patient-related factors such as age, size, life expectancy, comorbidities, plans for pregnancy, and lifestyle. In addition, surgeon- or operation-related factors should be considered. Technical aspects of implantation, ease of reoperation, and operative mortalities may tip the risk and benefit balance in a particular direction. We review currently available heart valve prostheses and the clinical factors that are involved in selection of a heart valve substitute.

Does antiphospholipid antibody syndrome affect bioprosthetic heart valve?

Cardiovascular involvements in antiphospholipid antibody syndrome have been recognized as a major complication of this disease. Furthermore, some papers report bioprosthetic heart valve also seems to be affected. A 32-year-old female with aortic regurgitation presented to our hospital. Further examination revealed high titer of anticardiolipin beta 2 glycoprotein 1 antibody, and she was diagnosed as having primary antiphospholipid antibody syndrome since the patient failed to match the criteria of systemic lupus erythematosus. Cardiopulmonary bypass was uneventfully conducted under systemic heparinization of usual dosage. Administration of warfarin sodium was started on the third postoperative day, and international normalized ratio was controlled from 2.0 to 2.5. On echocardiographic examination at 1 month, mean systolic gradient was 17 mmHg. Although transesophageal echocardiography at 2 years after surgery revealed no sign of valvular destruction or sclerosis, transaortic gradient had increased to 26 mmHg. Bioprosthetic stenosis was suspected probably due to pannus formation and the patient may have to undergo another valve replacement in the near future.

European experience with the Mosaic bioprosthesis

OBJECTIVE

The purpose of this study was to prospectively evaluate the clinical and hemodynamic performance of the Mosaic bioprosthesis (Medtronic, Inc, Minneapolis, Minn).

METHODS

The stented porcine bioprosthesis combines the amino-oleic acid antimineralization treatment and the zero-pressure differential fixation technique for improved tissue durability. From February 1994 to May 1999, a total of 561 patients underwent valve replacement with the Mosaic bioprosthesis at 5 centers in Europe: 461 in the aortic and 100 in the mitral position. There were 261 women and 300 men; mean age at implantation was 70 years (range, 23-89 years). Mean follow-up was 2.9 years (range, 0-6.2 years), with a total follow-up of 1710.1 patient-years.

RESULTS

Postoperative mortality was 4.2% per patient-year, including a valve-related mortality of 0.4% per patient-year. The freedom from event rates in the aortic position at 5 years and in the mitral position at 4 years were, respectively, 96.6% +/- 1.1% and 94.9% +/- 3.3% for primary thromboembolism, 96.4% +/- 5.0% and 87.1% +/- 4.8% for antithromboembolic-related hemorrhage, 99.1% +/- 0.5% and 100% for thrombosed prosthesis, 98.8% +/- 1.2% and 100% for structural valve deterioration, 98.8% +/- 0.7% and 100% for nonstructural dysfunction, 98.4% +/- 0.6% and 94.4% +/- 3.8% for endocarditis, and 95.4% +/- 1.6% and 95.3% +/- 3.7% for explant and reoperation. Mean pressure gradient values at 5 years ranged from 7.5 to 15.9 mm Hg in the aortic position and at 4 years from 2.0 to 6.9 mm Hg in the mitral position across all valve sizes.

CONCLUSIONS

Clinical and hemodynamic performance of the Mosaic bioprosthesis were very satisfactory during the first 6 years after clinical introduction.

Medtronic Mosaic porcine bioprosthesis: midterm investigational trial results

BACKGROUND

The midterm clinical and hemodynamic performance of the Medtronic Mosaic porcine bioprosthesis was evaluated in a regulatory trial.

METHODS

In nine Canadian centers, 802 bioprostheses (560 aortic and 242 mitral) were implanted between September 1994 and April 1999 in patients with a mean age of 70 years.

RESULTS

Survival for aortic valve replacement at 4 years was 84.4%+/-3.1%. Freedom from valve-related or unexplained death was 95.6%+/-1.9%; structural valve deterioration, 100.0%; reoperation, 96.2%+/-1.7%; major thromboembolism, 96.1%+/-1.8%; and major antithrombotic-related hemorrhage, 96.4%+/-1.7%. Echocardiographic derived mean systolic gradient was 13.4 mm Hg at 4 years with an indexed effective orifice area of 0.7 to 0.8 cm2/m2. A significant decrease in left ventricular mass was shown over time in all valve sizes. Survival for mitral valve replacement at 4 years was 79.2%+/-6.8%. Freedom from valve-related or unexplained death was 96.5%+/-3.4%; structural valve deterioration, 100%; reoperation, 97.0%+/-3.2%; major thromboembolism, 95.7%+/-3.8%; and major antithrombotic-related hemorrhage, 95.0%+/-4.2%. Echocardiographically measured averaged mean diastolic gradient was 4.5 mm Hg.

CONCLUSIONS

The Medtronic Mosaic bioprosthesis is safe and effective in both the aortic and mitral positions. The valve has low gradients in both positions and excellent left ventricular mass regression in the patients with aortic valve replacement.