Mitroflow Synergy Prostheses for Aortic Valve Replacement: 19 Years Experience With 1,516 Patients

Transcatheter versus surgical aortic valve replacement for severe aortic valve stenosis: Meta-analysis with trial sequential analysis

OBJECTIVES

Randomized controlled trials comparing transcatheter aortic valve implantation with surgical aortic valve replacement demonstrate conflicting evidence, particularly in low-risk patients. We aim to reevaluate the evidence using trial sequential analysis, balancing type I and II errors, and compare with conventional meta-analysis.

METHODS

Databases were searched for randomized controlled trials, which were divided into higher-risk and lower-risk randomized controlled trials according to a pragmatic risk classification. Primary outcomes were death and a composite end point of death or disabling stroke assessed at 1 year and maximum follow-up. Conventional meta-analysis and trial sequential analysis were performed, and the required information size was calculated considering a type I error of 5% and a power of 90%.

RESULTS

Eight randomized controlled trials (n = 5274 higher-risk and 3661 lower-risk patients) were included. Higher-risk trials showed no significant reduction in death at 1 year with transcatheter aortic valve implantation (relative risk, 0.93, 95% CI, 0.81-1.08, P = .345). Lower-risk trials suggested lower death risk on conventional meta-analysis (relative risk, 0.67, 95% CI, 0.47-0.96, P = .031), but trial sequential analysis indicated potential spurious evidence (P = .116), necessitating more data for conclusive benefit (required information size = 5944 [59.8%]). For death or disabling stroke at 1 year, higher-risk trials lacked evidence (relative risk, 0.90, 95% CI, 0.79-1.02, P = .108). In lower-risk trials, transcatheter aortic valve implantation indicated lower risk in conventional meta-analysis (relative risk, 0.68, 95% CI, 0.50-0.93, P = .014), but trial sequential analysis suggested potential spurious evidence (P = .053), necessitating more data for conclusive benefit (required information size = 5122 [69.4%]). Follow-up results provided inconclusive evidence for both primary outcomes across risk categories.

CONCLUSIONS

Conventional meta-analysis methods may have prematurely declared an early reduction of negative outcomes after transcatheter aortic valve implantation when compared with surgical aortic valve replacement.

The pathology of early failure in Mitroflow pericardial valve bioprosthesis (12A/LX)

BACKGROUND

Limited mid-term durability of 12A/LX Mitroflow bioprosthesis has been reported. Aim of the study was to ascertain the pathologic substrates and possible mechanisms of structural valve deterioration in explants from animals and humans.

METHODS

Nine aortic 12A/LX Mitroflow bioprostheses preserved in hypotonic solution and three aortic 12A/LX bioprostheses, preserved in isotonic solution, were explanted from juvenile sheep, mean time from implant 95.66 ± 36.04 days and 132.33 ± 28.88 days from implant respectively. One stented unimplanted 12A/LX Mitroflow preserved in isotonic colution before glutaraldeyde fixation served as control. Ten aortic 12A/LX Mitroflow bioprostheses were explanted from humans because of severe dysfunction: five children, (3 females and 2 males, mean age 14.19 ± 4.77 years, range 11-21), 26 ± 8.24 months from implant and 5 adults (4 females and 1 male, mean age 57.4 ± 19.85 years, range 31-72), 64.4 ± 26.94 months from implant. X-ray, histology, and transmission electron microscopy were carried out as well as spectroscopy for calcium (Ca++) and phosphorus (P) content in human explants.

RESULTS

Explants, from both animals and humans, showed cusp folding and stiffness, with coarse calcific deposits at gross examination and X-ray. Severe collagen denaturation, plasma insudation and massive calcification, involving both collagen and cell debris, were observed microscopically. Mean Ca++ content of 183.27 ± 62.48 and P content of 94.35 ±33.76 mg/g dry weight was found in children and Ca++ content of 205.49 ± 2.23 and P content of 99.75 ± 0.11 mg/g dry weight in adults. Obstructive fibrous tissue overgrowth was detected in 6 human cases.

CONCLUSIONS

Collagen denaturation was observed in pericardial Mitroflow 12A/LX bioprosthesis with premature structural valve deterioration. Optimal collagen fixation and preservation as well as phospholipids reduction by removing cell debris, as employed in the novel CROWN PRT Mitroflow bioprosthesis, are expected to solve the flaw and achieve long-term durability.

Aortic valve neocuspidization with autologous pericardium in adult patients: UK experience and meta-analytic comparison with other aortic valve substitutes

OBJECTIVES

We sought to provide further evidence on the safety and efficacy of aortic valve neocuspidization (AVNeo) using autologous pericardium in adult patients with aortic valve disease by reporting clinical and echocardiographic results from the first UK experience and performing a meta-analytic comparison with other biological valve substitutes.

METHODS

We reported clinical and echocardiographic outcomes of 55 patients (mean age 58 ± 15 years) undergoing AVNeo with autologous pericardium in 2 UK centres from 2018 to 2020. These results were included in a meta-analytic comparison between series on AVNeo (7 studies, 1205 patients, mean weighted follow-up 3.6 years) versus Trifecta (10 studies, 8705 patients, 3.8 years), Magna Ease (3 studies, 3137 patients, 4.1 years), Freedom Solo (4 studies, 1869 patients, 4.4 years), Freestyle (4 studies, 4307 patients, 7 years), Mitroflow (4 studies, 4760 patients, 4.1 years) and autograft aortic valve (7 papers, 3839 patients, 9.1 years).

RESULTS

In the present series no patients required intraoperative conversion. After mean follow-up of 12.5 ± 0.9 months, 3 patients presented with endocarditis and 1 required reintervention. The remaining patients had absent or mild aortic valve insufficiency with very low peak and mean transvalvular gradients (16 ± 3.7 and 9 ± 2.2 mmHg, respectively). Meta-analytic estimates showed non-significant difference between AVNeo and all but Magna Ease valves with regards to structural valve degeneration, reintervention and endocarditis. When compared Magna Ease valve, AVNeo and other valve substitutes showed an excess of valve-related events.

CONCLUSIONS

AVNeo is safe, associated with excellent haemodynamic profile. Its midterm risk of valve-related events is comparable to most biological valve substitutes. Magna Ease is potentially the best biological choice as far as risk of reintervention is concerned.

Eight-year outcomes for patients with aortic valve stenosis at low surgical risk randomized to transcatheter vs. surgical aortic valve replacement

Aims

The aims of the study were to compare clinical outcomes and valve durability after 8 years of follow-up in patients with symptomatic severe aortic valve stenosis at low surgical risk treated with either transcatheter aortic valve implantation (TAVI) or surgical aortic valve replacement (SAVR).

Methods and results

In the NOTION trial, patients with symptomatic severe aortic valve stenosis were randomized to TAVI or SAVR. Clinical status, echocardiography, structural valve deterioration, and failure were assessed using standardized definitions. In total, 280 patients were randomized to TAVI (n = 145) or SAVR (n = 135). Baseline characteristics were similar, including mean age of 79.1 ± 4.8 years and a mean STS score of 3.0 ± 1.7%. At 8-year follow-up, the estimated risk of the composite outcome of all-cause mortality, stroke, or myocardial infarction was 54.5% after TAVI and 54.8% after SAVR (P = 0.94). The estimated risks for all-cause mortality (51.8% vs. 52.6%; P = 0.90), stroke (8.3% vs. 9.1%; P = 0.90), or myocardial infarction (6.2% vs. 3.8%; P = 0.33) were similar after TAVI and SAVR. The risk of structural valve deterioration was lower after TAVI than after SAVR (13.9% vs. 28.3%; P = 0.0017), whereas the risk of bioprosthetic valve failure was similar (8.7% vs. 10.5%; P = 0.61).

Conclusions

In patients with severe aortic valve stenosis at low surgical risk randomized to TAVI or SAVR, there were no significant differences in the risk for all-cause mortality, stroke, or myocardial infarction, as well as the risk of bioprosthetic valve failure after 8 years of follow-up.

Clinical trial registration

URL: http://www.ClinicalTrials.gov. Unique identifier: NCT01057173.

Fifty years of the pericardial valve: Long-term results in the aortic position

It is now 50 years since the development of the first pericardial valve in 1971. In this time significant progress has been made in refining valve design aimed at improving the longevity of the prostheses. This article reviews the current literature regarding the longevity of pericardial heart valves in the aortic position. Side by side comparisons of freedom from structural valve degeneration are made for the valves most commonly used in clinical practice today, including stented, stentless, and sutureless valves. Strategies to reduce structural valve degeneration are also discussed including methods of tissue fixation and anti-calcification, ways to minimise mechanical stress on the valve, and the role of patient prosthesis mismatch.

Evaluation of hemodynamics after mitral valve replacement with the St Jude Medical Epic bioprosthesis: a Japanese single-center experience

To assess the early hemodynamics after mitral valve replacement (MVR) using the St Jude Medical (SJM) Epic bioprosthesis. MVR was performed using the SJM Epic bioprosthesis in 35 patients from June 2018 to April 2020; three patients were excluded because the postoperative transthoracic echocardiography (TTE) data were unavailable. Data from postoperative TTE at 1 week and 3 months after the procedure were reviewed. The mean mitral pressure gradient (mMPG) was calculated using a continuous wave Doppler method. Left ventricular outflow tract (LVOT) was calculated using a pulse wave Doppler method. The effective orifice area (EOA) was measured from pressure half time. There were 12 men (37.5%) and 20 women (62.5%) with a mean age of 75.9 years (61-88 years). The mean body surface area was 1.51 ± 0.22 cm². The 25 mm and 27 mm valves were used in more than 50% of cases. The mMPG was 4.9 ± 1.7 mmHg and 5.4 ± 1.6 mmHg at 1 week and 3 months after surgery, respectively. EOA was 2.18 ± 0.50 cm² and 2.31 ± 0.59 cm² at 1 week and 3 months after surgery, respectively. The peak velocity of the LVOT (n = 22) was 103.3 ± 21.3 cm/s and 106.8 ± 27.4 cm/s at 1 week and 3 months after surgery, respectively. No findings suggested paravalvular regurgitation and LVOT obstruction. Using the SJM Epic bioprosthesis in MVR resulted in satisfactory hemodynamics in the early postoperative period, even with small valve sizes. Further accumulation of cases and evidence, including mid- to long-term results, is required in the future.

[Safety of biological valves for aortic valve replacement: A systematic review and meta-analysis]

OBJECTIVE

To provide a comprehensive and contemporary overview of the long-term safety outcomes after aortic valve replacements (AVR) with conventional biological heart valve (stented or stentless).

METHODS

English databases (Medline, Embase, Web of Science, CENTRAL, and ClinicalTrial.gov) and Chinese databases (CNKI, VIP, WanFang, and SinoMed) were searched systemically from January 1, 2000 to January 26, 2019. Eligible randomized controlled trials, non-randomized clinical trials, cohort studies (retrospective or prospective), and unselected case series were included. Strict screening of the obtained literature was conducted to extract relevant data by two reviewers. Other inclusion criteria were studied reporting on outcomes of AVR with biological valves (stented or stentless), with or without coronary artery bypass grafting (CABG) or valve repair procedure, with mean follow-up length equal to or longer than 5 years. We excluded studies that reported only a specific patient group (e.g., patients with renal failure, or pregnancy), without the report of biological valve type, or with study population size less than 100. The meta-analysis was performed using Stata 14.0 software.

RESULTS

In this study, 53 papers (in total 57 study groups) involving 47 803 patients were included. (1) The all-cause mortality was 6.33/100 patient-years (95%CI: 5.85-6.84). Subgroup analysis showed that the mortality rates of porcine and bovine valve prostheses were 5.69/100 patient-years (95%CI: 5.05-6.41) and 7.29/100 patient-years (95%CI: 6.53-8.13), respectively. The all-cause mortality rates for stented and stentless valve were 6.69/100 patient-years (95%CI: 6.12-7.30) and 5.21/100 patient-years (95%CI: 4.43-6.14), respectively. (2) The incidence rate of thromboembolism was 1.16/100 patient-years (95%CI: 0.96-1.40), the incidence rate of permanent pacemaker (PPM) implantation was 1.08/100 patient-years (95%CI: 0.75-1.54), the incidence rate of stroke was 0.74/100 patient-years (95%CI: 0.51-1.06), the incidence rate of structural valve dysfunction (SVD) was 0.73/100 patient-years (95%CI: 0.59-0.91), the incidence rate of major bleeding was 0.52/100 patient-years (95%CI: 0.41-0.65), the incidence rate of endocarditis was 0.38/100 patient-years (95%CI: 0.33-0.44), and the incidence rate of non-structural valve dysfunction (NSVD) was 0.20/100 patient-years (95%CI: 0.13-0.31). The total reoperation rate for biological aortic valve was 0.77/100 patient-years (95%CI: 0.65-0.91), and the SVD related reoperation rate was 0.46/100 patient-years (95%CI: 0.36-0.58).

CONCLUSION

The all-cause mortality for conventional biological AVR was 6.33/100 patient-years. Thromboembolism, PPM implantation, reoperation, stroke, and SVD were major long term complications.

The Use of Biological Heart Valves

BACKGROUND

Biological heart-valve prostheses have undergone continuous devel- opment up to the present, and technological advances have been made in catheter- assisted valve systems (transcatheter aortic valve implantation, TAVI) and minimally invasive routes of application. These parallel trends have led to major changes in therapeutic strategies, widening the spectrum of patients who are candidates for biological aortic valve implantation.

METHODS

This review is based on pertinent publications retrieved by a systematic search in PubMed employing the search terms "conventional biological aortic pros- thesis," "rapid deployment prosthesis," and "transcatheter aortic valve implantation/ replacement."

RESULTS

Among biological heart-valve prostheses, a distinction is drawn between stented (conventional, rapid-deployment, and catheter-assisted) and non-stented types. The long-term durability of conventional, surgically implantable biological valve protheses is by far the best documented: the reported 5-year reoperation rates range from 13.4% to 36.6%, and the pacemaker implantation rate is ca. 4%. Rapid-deployment prostheses combine the advantages of conventional and ca- theter-assisted techniques and facilitate minimally invasive approaches. The TAVI method is currently recommended for high- and intermediate-risk patients, while conventional valve replacement remains the method of choice for those at low risk. Rapid-deployment and TAVI prostheses is associated with a higher pacemaker im- plantation rate than conventional prostheses: these rates are 8.5-15.3% for TAVI and 6.0-8.8% for rapid-deployment valves. The intermediate-term durability of catheter-assisted and rapid-deployment prostheses appears promising, but their long-term durability is still unclear.

CONCLUSION

The further development of biological heart-valve prostheses in the form of improved conventional, transcatheter, and rapid-deployment prostheses now enables individualized treatment. Before any such procedure is performed, the car- diac team must assess the patient's risk profile and the advantages and disadvan- tages of each type of prosthesis to determine which is best.

Influence of Mitroflow bioprosthesis structural valve deterioration on cardiac morbidity

Background

This study investigated the extent and nature of cardiac morbidity and cause of mortality in patients with Mitroflow structural valve deterioration (SVD).

Methods

A retrospective study was performed examining the medical records of patients who had received Mitroflow bioprosthesis between February 2001 and April 2014 and died during this period. A total of 211 patients were identified and included in the analyses. To determine the cause of mortality, cases were divided into three predefined groups: cardiovascular death due to SVD (group 1), cardiovascular death with no SVD (group 2) and non-cardiovascular death without SVD (group 3).

Results

Overall mortality in this study was 7.6% at 1 year, 46.4% at 5 years and 97.2% at 10 years. In group 1, 53 patients (25%) died; in group 2, 59 patients (28%) died; and in group 3, 99 patients (47%) died. Hospitalisation for congestive heart failure was observed in 49.1% in the SVD group vs. 10.2 and 13.1% in the two other groups, p < 0.001. Hospitalisation for endocarditis was also significantly higher in the SVD group (11.3%) than in the two other groups (6.8 and 0%), p < 0.05. Hospitalisation due to myocardial infarction, cerebral stroke, arrhythmia or other cardiac-related diseases was not significantly different between groups.

Conclusion

Structural valve deterioration in Mitroflow bioprosthesis was associated with a high prevalence of hospital admissions due to congestive heart failure and endocarditis. Patients with Mitroflow bioprosthesis should be systematically and routinely followed with echocardiography, and reoperation should be considered if SVD has developed.

Structural valve deterioration of bioprosthetic aortic valves: An underestimated complication

OBJECTIVES

Structural valve deterioration (SVD) remains a major bioprosthesis-related complication, as recently described for the Mitroflow valve (models LX and 12A) (LivaNova, London, United Kingdom). The real incidence of the SVD risk remains unclear, often due to methodologic pitfalls by systematically using the Kaplan-Meier estimator and/or the Cox model. In this report, we propose for the first time a precise statistical modeling of this issue.

METHODS

Five hundred sixty-one patients who underwent aortic valve replacement with the aortic Mitroflow valve between 2002 and 2007 were included. We used an illness-death model for interval-censored data. Median follow-up was 6.6 years; 103 cases of SVD were diagnosed.

RESULTS

The 4-year and 7-year SVD cumulative incidences after the first anniversary of surgery were 15.2% (95% confidence interval, 11.9-19.1) and 31.0% (95% confidence interval, 25.8-37.2), respectively. Female gender, dyslipidemia, chronic obstructive pulmonary disease, and severe patient-prosthesis mismatch were significant risk factors of SVD. The occurrence of SVD was associated with a 2-fold increase in the risk of death.

CONCLUSIONS

Appropriate statistical models should be used to avoid underestimating the SVD complication associated with worse long-term survival.

Structural valve deterioration in the Mitroflow biological heart valve prosthesis

OBJECTIVES

Concern has been raised regarding the long-term durability of the Mitroflow biological heart valve prosthesis. Our aim was to assess the incidence of structural valve degeneration (SVD) for the Mitroflow bioprosthesis in a nationwide study in Denmark including all patients alive in Denmark who had received a Mitroflow aortic bioprosthesis since 2000.

METHODS

Patients alive in Denmark with a Mitroflow bioprosthesis implanted since January 2000 were invited to participate in a nationwide cross-sectional study with a predefined definition of SVD. Of 1552 patients, 861 patients had died and 47 patients had been reoperated with 40 reoperations due to SVD. The remaining 644 patients were invited for evaluation; 574 patients accepted and were evaluated for SVD. The incidence of SVD was calculated using competing risk regression analysis with death as the competing event.

RESULTS

A total of 173 patients were diagnosed with SVD by echocardiography. Of these, 64 (11%) patients had severe SVD and 109 (19%) patients moderate SVD. Severe SVD was associated with the age of the prosthesis and small prosthesis size [Size 21: hazard ratio (95% confidence interval, CI) 2.72 (0.97-8.56), P = 0.06; Size 19: 6.26 (1.63-24.06), P = 0.008]. The cumulative incidences of reoperation or severe SVD at Year 9 were 12.5% for Size 19, 7.6% for Size 21 and 3.1 (1.2-6.4)% for Size 23. Median survival in patients with prosthesis Sizes 23-29 was 6.4 (95% CI 5.7-7.0) years, with Size 21 it was 6.5 (95% CI 5.9-7.1) years and with Size 19 it was 6.9 (95% CI 5.7-8.2) years (P = 0.78).

CONCLUSIONS

The incidence of undetected severe SVD was as high as the incidence of operated SVD. The overall risk for SVD is high for the Mitroflow bioprosthesis, especially if the prosthesis is small and older than 5 years.

Ten-year results of aortic valve replacement with first-generation Mitroflow bioprosthesis: is early degeneration a structural or a technical issue?

OBJECTIVES

Concerns have been raised about the durability of the first-generation Mitroflow aortic bioprosthesis (model 12 A-LX) due to the lack of anticalcification treatment. This study reflects a 10-year experience with this prosthesis for aortic valve replacement.

METHODS

From June 2003 to May 2012, the Mitroflow prosthesis was used for aortic valve replacement in 510 patients, of whom only 467 with complete clinical follow-up were included for analysis. Study end-points were survival and incidence of structural valve degeneration (SVD). Analysis of SVD was based on cumulative incidence function and competing-risk Cox regression.

RESULTS

The mean patient age was 76.4 ± 6.1 years. Valve sizes from 23 to 25 were used in 70.4%, whereas sizes from 19 to 21 were used in only 19.2%, thereby avoiding patient-prosthesis mismatch in 89.1%. Within a median follow-up time of 6.6 years (interquartile range 4.4), a cumulative 2375 patient-years, the survival rate was 86.2%, 67.3% and 33.3% at 1, 5 and 10 years, respectively. The cumulative incidence of SVD, with death as a competing risk, was 0%, 0.7% and 6.2% at 1, 5 and 10 years, respectively. Only age <75 years tended to affect the late hazard of SVD (hazard ratio 0.50, 95% confidence interval 0.23-1.08, P  = 0.08), regardless of valve-specific issues.

CONCLUSIONS

The data do not support the concerns about early accelerated structural degeneration of the first-generation Mitroflow bioprosthesis used for aortic valve replacement in patients older than 75 years. We postulate that limiting the number of small prostheses using a proper implantation technique has enhanced the reduction in risk of significant patient-prosthesis mismatch as the main determinant of early SVD.

Real Structural Valve Deterioration of the Mitroflow Aortic Prosthesis: Competing Risk Analysis

INTRODUCTION AND OBJECTIVES

The Mitroflow aortic prosthesis is a bovine pericardial bioprosthesis specially designed to increase the valve area in relation to its size. There is controversy regarding the pattern of structural valve deterioration (SVD). Our aim was to determine the cumulative incidence of SVD, risk factors influencing its occurrence, and its impact on mortality.

METHODS

A total of 1028 patients were clinically and echocardiographically followed up. Because the study population was elderly and had heart disease, we used a competing risk analysis.

RESULTS

The percentage of patients with SVD at 5 years was 4.22% (95%CI, 2.96-5.81) and was 15.77% at 8 years (95%CI, 12.46-19.43). The incidence was higher for small valves (19mm and 21mm) reaching 6.43% at 5 years (95%CI, 4.48-8.84) and 20.06% at 8 years (95%CI, 15.53-25.01). Severe patient-prosthesis mismatch (PPM) influenced the incidence of SVD (_sHR, 3.53; 95%CI, 2.20-5.66; P < .001) but moderate PPM had no impact. The most powerful predictor of mortality was the presence of SVD (HR, 4.59; 95%CI, 2.91-7.22; P < .001).

CONCLUSIONS

This study used a definition based on the increase in the transprosthetic gradient and found a higher incidence of SVD of the Mitroflow prosthesis than that reported by other series, especially for sizes 19mm and 21mm and in patients with severe PPM. The incidence of SVD increased exponentially from the fifth year after implantation and its occurrence led to a 4.5-fold increase in the risk of death.

Effect of bioprostheses anti-calcification treatment: comparative follow-up between Mitroflow LX and Magna pericardial xenografts using a propensity score-weighted analysis

Objectives

The efficacy of anti-calcification treatment of bioprosthetic heart valves remains unclear. The aim of this study was to compare the clinical outcomes between Mitroflow LX valve, without anti-calcification treatment, and the Carpentier-Edwards Perimount Magna (P-Magna), with anti-calcification treatment.

Methods

Between 2005 and 2012, 625 consecutive patients underwent aortic valve replacement either with a Mitroflow LX ( n  = 329) or a P-Magna ( n  = 296). Variables regarding patient-related risk factors and operative data were accounted for an inverse probability of treatment weighting analysis. Then, adjusted survival outcomes and the rate of structural valve disease (SVD) were assessed for each group.

Results

Mean follow-up times were 4.1 ± 2.29 years and 3.9 ± 2.63 years, respectively ( P  = 0.34). Adjusted overall survival rate was higher in the P-Magna group than in the Mitroflow LX group at 8 years (69.1% vs 51.9%, respectively) [HR = 1.44, 95% CI: 1.01 to 2.06; P  = 0.0467]. Similarly, the 8-year cardiac-related survival rate was also higher in the P-Magna group [HR = 1.99, 95% CI: 1.19 to 3.32; P  = 0.0083]. One patient (0.8%) with P-Magna and 23 patients (18.5%) with Mitroflow LX group developed SVD (0.24% per patient-year vs 4.5% per patient-year, respectively; P  < 0.001). At 5 and 8 years, valve-related survival rates did not differ significantly between both groups [HR = 1.67, 95% CI: 0.95 to 2.95; P  = 0.075].

Conclusions

The P-Magna prosthesis showed significantly better overall and cardiac-related survival than the Mitroflow LX. The higher early SVD and reoperation rates seen with the Mitroflow LX prosthesis did not impact negatively on valve-related survival.

Durability after aortic valve replacement with the Mitroflow versus the Perimount pericardial bioprosthesis: a single-centre experience in 2393 patients

OBJECTIVES

This study compares the durability and risk of reoperation in patients undergoing aortic valve replacement (AVR) with either a Mitroflow or a Carpentier-Edwards (CE) pericardial bioprosthesis. Since AVR with bioprosthetic valves has increased progressively in recent years as compared to mechanical valves, especially in patients aged 60-70 years, there has been renewed interest in the long-term durability of current pericardial bioprostheses.

METHODS

We compared 440 AVR with Mitroflow valves with 1953 AVR with CE pericardial valves implanted from 1999 to 2014 with regard to reoperation, reoperation for structural valve deterioration (SVD) and all-cause mortality.

RESULTS

Ten-year freedom from explant of any cause was higher for CE Perimount (98 ± 0.7%) than for Mitroflow (95 ± 1.4%, P < 0.01). Reasons for explant for CE Perimount were SVD (n = 2), endocarditis (n = 8) and paraprosthetic leak (n = 10). The reasons for explant for Mitroflow were SVD (n = 11), endocarditis (n = 3) SVD and pericarditis (n = 1) and paraprosthetic leak (n = 2). Ten-year freedom from explant due to SVD was higher for CE Perimount (100%) than for Mitroflow (96%) (P < 0.01). In small aortic annuli (bioprosthesis size 19-21 mm), freedom from SVD at 10 years for CE Perimount and Mitroflow was 100 versus 96%, respectively. By multivariate analysis, it was found that bioprosthesis size was not a risk factor for SVD. The choice of valve type could not be demonstrated to influence long-term survival.

CONCLUSIONS

The Mitroflow pericardial bioprosthesis provides less than optimal mid- and long-term durability compared with the CE Perimount pericardial valve, especially for small aortic diameter implants (19 and 21 mm). This study hereby confirms the existence of a real risk of valvular deterioration of the Mitroflow valve that might compromise the prognosis of the patients.

Improved quality of life two-years post Transcatheter Aortic Valve Replacement for a regurgitant aortic homograft

The limited durability of prosthetic cardiac valves together with an aging population will present ongoing management challenges. This paper describes the case of an 82 year-old male with symptomatic severe regurgitation in an aortic homograft which remains successfully treated with Transcatheter Aortic Valve Replacement (TAVR) at two-year follow-up.

Clinical evaluation of new heart valve prostheses: update of objective performance criteria

This article summarizes the long-term clinical results of the Food and Drug Administration-approved heart valves, provides current updates to the objective performance criteria (OPC) used to evaluate new heart valve prostheses, and documents the steps that the International Organization for Standardization Committee used to arrive at the updated OPC. Data were extracted from 19 Food and Drug Administration summaries of safety and effectiveness data reports (31 series) and 56 literature articles (85 series) published from 1999 to 2012. The OPC were calculated for five valve-related complications by valve type (mechanical and bioprosthetic) and valve position (aortic and mitral).

Custodiol for myocardial protection and preservation: a systematic review

INTRODUCTION

Custodiol cardioplegia is attractive for minimally invasive cardiac surgery, as a single dose provides a long period of myocardial protection. Despite widespread use in Europe, there is little data confirming its efficacy compared with conventional (blood or crystalloid) cardioplegia. There is similar enthusiasm for its use in organ preservation for transplant, but also a lack of data. This systematic review aimed to assess the evidence for the efficacy of Custodiol in myocardial protection and as a preservation solution in heart transplant.

METHODS

Electronic searches were performed of six databases from inception to October 2013. Reviewers independently identified studies that compared Custodiol with conventional cardioplegia (blood or extracellular crystalloid) in adult patients for meta-analysis; large case series that reported results using Custodiol were analyzed. Next, we identified studies that compared Custodiol with other organ preservation solutions for organ preservation in heart transplant.

RESULTS

Fourteen studies compared Custodiol with conventional cardioplegia for myocardial protection in adult cardiac surgery. No difference was identified in mortality; there was a trend for increased incidence of ventricular fibrillation in the Custodiol group that did not reach statistical significance. No difference was identified in studies that compared Custodiol with other solutions for heart transplant.

CONCLUSIONS

Despite widespread clinical use, the evidence supporting the superiority of Custodiol over other solutions for myocardial protection or organ preservation is limited. Large randomised trials are required.

Bioprosthetic Heart Valves: Impact of Implantation on Biomaterials

Prosthetic heart valves are commonly used in the treatment of valvular heart disease. Mechanical valves are more durable than the bioprosthetic valves; however, the need for long-term anticoagulant therapy renders them unsuitable for some patient groups. In this paper we discuss the different types and models of bioprosthesis, and in particular, pericardial bioprosthesis. We also discuss the preimplantation preparation processes, as well as their postimplantation changes and modes of failure.

Choice of prosthetic heart valve in adults an update

In the last 7 years, more data have reconfirmed that patients' comorbid conditions are very important factors determining patient outcomes. Prosthetic heart valves (PHVs) that require aortic root replacement in the absence of aortic root disease are associated with poorer outcomes. For the vast majority of patients, the choice of PHV is between a mechanical valve and a stented bioprosthesis. The choice is largely dependent upon the age of the patient at the time of PHV implantation and on which complication the patient wants to avoid: specifically, anticoagulation therapy and its complications with the mechanical valve, and structural valve deterioration with a bioprosthesis. Data on the pros and cons of the choices and exceptions to the rules are discussed, and a new algorithm is developed.

Evaluation and management of aortic valve and root disease

Aortic valve disease manifests in the form of stenosis, regurgitation, or some combination, yielding either excessive afterload and/or excessive preload on the left ventricle. Aortic root disease may affect valvular function, causing regurgitation; may simply be coexistent with stenotic aortic valvular disease; or may exist despite normal aortic valve function. Indications for intervening on aortic valve or root disease are determined by the presence of symptoms, by the pathology's impact on left ventricular function, or by the inherent risk of aortic catastrophe (dissection, disruption, or sudden death). Aortic valvular and root diseases are primarily treated by surgical replacement of the pathologic structures. Mechanical aortic valve replacement has long-term durability but requires continuous anticoagulation. Bioprostheses do not require anticoagulation but have more limited durability. Valve-sparing aortic root replacement and aortic valve repair offer the potential for indefinite durability without the need for anticoagulation but are technically more difficult to perform and require more stringent selection criteria based on determining the reparability of an aortic valve. Emerging percutaneous valve technologies offer new hope for patients who are not candidates for aortic valve surgery, but the applicability and durability of percutaneous aortic valves are not yet known. Timely and appropriate intervention in aortic valve and root disease can result in the restoration of a normal life span for patients with aortic valvular and/or root disease.

Self-management of oral anticoagulation therapy improves long-term survival in patients with mechanical heart valve replacement

BACKGROUND

The Early Self-Controlled Anticoagulation Trial has demonstrated that in patients with mechanical heart valve replacement self-management of oral anticoagulation results in less major thromboembolic events than conventional measurement by the general practitioner. However, the effects of self-management on long-term survival are currently not known.

METHODS

Nine hundred thirty patients participated in a follow-up study of the aforementioned trial (488 from the self-management group and 442 from the conventional group). Long-term survival was assessed 12 years after the study began using the intent-to treat analysis as well as the per protocol analysis. Univariate and multivariate analyses were performed in order to assess independent predictors of survival.

RESULTS

In total, the 930 patients accrued 8,315 patient-years of observation. During follow-up, 236 patients died. According to the intent-to treat analysis, 10-year survival was 76.1% in the conventional group and 84.5% in the self-management group. The corresponding values for the per protocol analysis were 67.7% and 80.6%, respectively. Age, kind of valve surgery, and study group were independent predictors of survival. Self-management of oral anticoagulation increased long-term survival by 23% (intent-to-treat analysis) and 33% (per protocol analysis), respectively, compared with conventional measurement by the general practitioner. Possible reasons for these advantageous results in the self-management group are fewer thromboembolic events due to a higher percentage of international normalized ratio values lying in the target range compared with the conventional group.

CONCLUSIONS

Data indicate that self-management of oral anticoagulation is a promising strategy in order to increase long-term survival in patients with mechanical prosthetic valves.

Reoperation of the Aortic Valve in Octogenarians

BACKGROUND

Because of increasing life expectancy of patients with heart valve replacement and a limited durability of heart valve bioprostheses, cardiac reoperation becomes necessary in a significant percentage of patients. Reliable data on mortality and risk factors in octogenarians after replacement of aortic valve prostheses are scanty, however.

METHODS

We retrospectively analyzed 71 patients aged 80 years and older who underwent cardiac reoperation of the aortic valve (69 bioprostheses, 2 mechanical prostheses) between 1991 and 2004 at our heart center. Survival rate of the study cohort was compared with a control group of octogenarians matched for age, sex, and year of aortic valve replacement. To assess predictors of 30-day survival and 3-year survival, we performed univariate and multivariate analyses.

RESULTS

Survival rates at 30 days, 1 year, 3 years and 5 years were 83.6%, 76.1%, 70.8%, and 51.3%, respectively. Results did not differ significantly between the study cohort and the controls. Patients with reoperation had an estimated median survival of 5.6 years. Postoperative complications such as low cardiac output syndrome and intestinal failure were the only independent predictors of 30-day survival (p = 0.020 and p = 0.015, respectively). Low cardiac output, intestinal failure, and diabetes mellitus were independent predictors of 3-year survival (p = 0.001 to 0.033).

CONCLUSIONS

Our data demonstrate that it is possible to achieve an acceptable outcome in octogenarians who have reoperation of the aortic valve prosthesis. Early and mid-term survival is predominantly influenced by unexpected postoperative complications and not by preoperative risk factors, with the exception of diabetes mellitus.