Bioprosthetic Valves In Patients Research Articles

Outcomes of surgical valve replacements for radiation-induced valvulopathy

ObjectivePatients with cancer who receive radiation therapy to the thorax often develop radiation-induced heart disease (RIHD) decades later. Previous chest radiation is associated with elevated perioperative risk of complications and mortality after cardiac surgery. Whether the type of valve (mechanical vs bioprosthetic) used affects outcomes in patients with RIHD is unknown. MethodsThis retrospective review analyzed the characteristics and postoperative outcomes of patients with a previous history of chest radiation for Hodgkin or non-Hodgkin lymphoma who underwent surgical valve replacement at a single institution between 2000 and 2021. Both 30-day perioperative outcomes and long-term survival were assessed. ResultsPatients who received mechanical valve tended to be younger, have more valves replaced, and have undergone previous coronary artery bypass grafting than bioprosthetic valve recipients. Valve type alone did not alter perioperative complications or overall survival. Median survival was 11.0 years in mechanical and 10.9 years in bioprosthetic valve patients (P = .930). Twelve patients underwent valve reinterventions (6 mechanical, 6 bioprosthetic), and 3 underwent transplant. Single-valve (aortic valve or mitral valve) recipients fared better with median survival of 13.3 years compared with 6.2 years in those who underwent combined aortic valve replacement plus mitral valve replacement (P < .0001). ConclusionsPatients with RIHD who undergo surgical valve replacement have similarly suboptimal short- and long-term outcomes regardless of mechanical versus bioprosthetic valve type. Those who required combined aortic and mitral valve replacement had especially high 10-year overall mortality. Further investigation in a larger dataset including transcatheter approaches is warranted.

Abstract 14172: Surgical Aortic Valve Replacement Using Contemporary Mechanical versus Bioprosthetic Valves in Patients Aged 50 to 70 Years: Long-Term Outcomes

Background: Choosing either a mechanical or a bioprosthetic valve during surgical aortic valve replacement (AVR) in middle-aged patients is still controversial, especially with contemporary advancements in valve technology. Aims: To evaluate long-term survival and major morbidity in patients aged 50-70 years undergoing AVR using contemporary mechanical and bioprosthetic valves. Methods: A retrospective study was performed using the TriNetX global database to identify patients aged 50 to 70 years who had primary isolated surgical AVR from 2014 to 2020. Patients who had transcatheter AVR, concomitant, or prior cardiac surgery were excluded. Patients were stratified into 2 groups: mechanical and bioprosthetic. A 1:1 propensity-score matching was performed to control for baseline differences between the two cohorts. The primary endpoint was all-cause mortality and secondary endpoints were stroke, major bleeding, and reoperation over a follow-up period of 8 years. Results: A total of 1,138 propensity-matched patients were included in each group. There was no significant difference in survival, stroke, or reoperation rates between the two groups. Survival probability at the end of the follow-up period was 76.6% in the mechanical group and 80.1% in the bioprosthetic group (HR, 0.946 [95% CI, 0.702, 1.276]) (Figure 1). A total of 137(12%) vs 119 (10.4%) patients had stroke in the mechanical vs the bioprosthetic group, respectively (HR, 1.08 [95% CI, 0.851-1.392]). A total of 19 (1.7%) vs 17 (1.5%) patients had reoperation in the mechanical, and the bioprosthetic valve group, respectively (HR, 1.01 [95% CI, 0.526, 1.951]). There were higher major bleeding events in the mechanical group, 266 (23.4%) vs 163 (14.3%) in the bioprosthetic group, (HR, 1.64 [95% CI, 1.353, 1.999]). Conclusion: Contemporary bioprosthetic valves could be a reasonable option for AVR in patients aged 50 to 70 years with less major bleeding risk and similar survival, stroke, and reoperation rates.

Extracorporeal membrane oxygenation for postcardiotomy cardiogenic shock after valve replacement.

Limited data evaluated the outcomes of extracorporeal membrane oxygenation (ECMO) in patients with prosthetic valves. This study aimed to compare the outcomes of ECMO support for postcardiotomy cardiogenic shock in patients with mechanical versus bioprosthetic valves. This retrospective study included patients with ECMO support for postcardiotomy cardiogenic shock after valve replacement. Patients were grouped into bioprosthetic (n = 49) and mechanical valve (n = 22) groups. There were no differences in ECMO duration, inotropic support, intra-aortic balloon pump (IABP), stroke, duration of ICU, and hospital stay between groups. Postoperative thrombosis occurred in 2 patients with bioprosthetic valves (5.41%) and 2 with mechanical valves (14.29%), p = .30. All patients with thrombosis had central ECMO cannulation, concomitant IABP, and inotropic support during ECMO. All thrombi were related to the mitral valve. Three patients with thrombi had hospital mortality.Survival at 6, 12, and 36months for bioprosthetic valve patients was 30.88%, 28.55%, and 25.34% and for mechanical valves was 36.36% for all time intervals (Log-rank p = .93). One patient had bioprosthetic aortic valve endocarditis after 1year. Three patients with bioprosthetic valves had structural valve degeneration after 1, 2, and 5years. Outcomes of ECMO in patients with prosthetic valves are comparable between bioprosthetic and mechanical valves. Thrombosis might occur in both valve types and was associated with high mortality. ECMO could affect the long-term durability of the bioprosthetic valves.

Durability of Bioprosthetic Valves in Patients on Dialysis.

This study focused on clarifying the durability of bioprosthetic valves in current practice. A total of 238 consecutive patients who underwent aortic valve replacement at a single institution from 2011 to 2020 were reviewed. We evaluated valve-related outcomes such as structural valve deterioration (SVD), especially in dialysis patients who received bioprosthetic valve. Among the tissue valves implanted in 212 patients, 5 SVDs were recorded and 3 valves were replaced. All early valve failures occurred in relatively young dialysis patients and were recorded 3 to 5 years after the initial operation. Freedom from SVD at 6 years was 49.9% in patients on dialysis, compared with 100% in non-dialysis patients. Predictors of better survival in dialysis patients were better preoperative functional class and larger prosthetic valve size. The durability of bioprosthetic valves in the aortic position was suboptimal in dialysis patients. Mechanical valves can be an option for young, healthy dialysis patients with a large aortic valve annulus.

Allergic response to medical products in patients with alpha-gal syndrome

BackgroundGalactose-α-1,3-galactose (alpha-gal) is a carbohydrate that is ubiquitously expressed in all mammals except for primates and humans. Patients can become sensitized to this antigen and develop alpha-gal syndrome (AGS), or a red meat allergy. Symptoms range from generalized gastroenteritis and malaise to anaphylaxis, and in endemic areas, the prevalence can be as high as 20%. Although AGS patients commonly avoid alpha-gal by avoiding meat, patients have also developed symptoms due to animal-derived medical products and devices. With the rise in transcatheter aortic valve replacement, we investigate the immunogenicity of common cardiac materials and valves. ObjectiveTo assess the in vitro immunoglobulin E response toward common medical products, including cardiac patch materials and bioprosthetic valves in patients with AGS. MethodsImmunoblot and immunohistochemistry techniques were applied to assess immunoglobulin E reactivity to various mammalian derived tissues and medical products for patients with AGS. ResultsAGS serum showed strong reactivity to all of the commercially available, nonhuman products tested, including various decellularized cardiac patch materials and bioprosthetic aortic valves. AGS serum did not react to tissues prepared using alpha-gal knockout pigs. ConclusionsDespite commercial decellularization processes, alpha-gal continues to be present in animal-derived medical products, including bioprosthetic valves. Serum from patients with AGS demonstrates a strong affinity for these products in vitro. This may have serious potential implications for sensitized patients undergoing cardiac surgery, including early valve failure and accelerated coronary artery disease.

Impact of the Trifecta bioprosthetic valve in patients with low-flow severe aortic stenosis

Aortic stenosis (AS) is the most common valve disorder in advanced age. Previous reports have shown that low-flow status of the left ventricle is an independent predictor of cardiovascular mortality after surgery. The Trifecta bioprosthesis has recently shown favorable hemodynamic performance. This study aimed to evaluate the effect of the Trifecta bioprosthesis, which has a large effective orifice area, in patients with low-flow severe AS who have a poor prognosis. We retrospectively evaluated 94 consecutive patients with severe AS who underwent aortic valve replacement (AVR). Patients were divided into two groups according to the stroke volume index (SVI): low-flow (LF) group (SVI < 35 ml/m2, n = 22) and normal-flow (NF) group (SVI ≥ 35 ml/m2, n = 72). Patients’ characteristics and early and mid-term results were compared between the two groups. There were no differences in patients’ characteristics, except for systolic blood pressure (LF:NF = 120:138 mmHg, p < 0.01) and the rate of atrial fibrillation between the groups. A preoperative echocardiogram showed that the pressure gradient was higher in the NF group than in the LF group, but aortic valve area was similar. The Trifecta bioprosthesis size was similar in both groups. The operative outcomes were not different between the groups. Severe patient–prosthesis mismatch (PPM) (< 0.65 cm2/m2) was not observed in either of the groups. There were no significant differences in mid-term results between the two groups. The favorable hemodynamic performance of the Trifecta bioprosthesis appears to have the similar outcomes in the LF and NF groups. AVR with the Trifecta bioprosthesis should be considered for avoidance of PPM, particularly in AS patients with LV dysfunction.

Durability of bioprosthetic aortic valves in patients under the age of 60\u2009years \u2013 rationale and design of the international INDURE registry

BackgroundThere is an ever-growing number of patients requiring aortic valve replacement (AVR). Limited data is available on the long-term outcomes and structural integrity of bioprosthetic valves in younger patients undergoing surgical AVR.MethodsThe INSPIRIS RESILIA Durability Registry (INDURE) is a prospective, open-label, multicentre, international registry with a follow-up of 5 years to assess clinical outcomes of patients younger than 60 years who undergo surgical AVR using the INSPIRIS RESILIA aortic valve. INDURE will be conducted across 20–22 sites in Europe and Canada and intends to enrol minimum of 400 patients. Patients will be included if they are scheduled to undergo AVR with or without concomitant root replacement and/or coronary bypass surgery.The primary objectives are to 1) determine VARC-2 defined time-related valve safety at one-year (depicted as freedom from events) and 2) determine freedom from stage 3 structural valve degeneration (SVD) presenting as morphological abnormalities and severe haemodynamic valve degeneration at 5 years. Secondary objectives include the assessment of the haemodynamic performance of the valve, all stages of SVD, potential valve-in-valve procedures, clinical outcomes (in terms of New York Heart Association [NYHA] function class and freedom from valve-related rehospitalisation) and change in patient quality-of-life.DiscussionINDURE is a prospective, multicentre registry in Europe and Canada, which will provide much needed data on the long-term performance of bioprosthetic valves in general and the INSPIRIS RESILIA valve in particular. The data may help to gather a deeper understanding of the longevity of bioprosthetic valves and may expand the use of bioprosthetic valves in patients under the age of 60 years.Trial registrationClinicalTrials.gov identifier: NCT03666741 (registration received September, 12th, 2018).

Meta-Analysis of Clinical Outcomes of Tricuspid Valve Replacement

AbstractBackground: The long-term results of Tricuspid Valve Replacement (TVR) depend on factors related to the original valve disease more than on the prosthesis type. Tricuspid valve prosthesis; either mechanical or bioprosthetic, should be chosen according to the individual patient's characteristics.Aim of Study: The aim of the study was to analyze the clinical results of tricuspid valve replacement, comparing the different types of tricuspid valve prostheses.Patients and Methods: A meta-analysis study was done to evaluate TVR results in adults in the literature published in the period of 20 years “1995: 2015”, focusing on literature published in English comparing mechanical valves to bio-prosthetic valves. We performed a search over published literature of different databases “Embase, PubMed, Ovid, Justor, Science Direct, and Wiley Blackwell.”Results: The total of 17 studies evaluating 1020 mechanical valve and 1199 bioprosthetic valve patients were included in the meta-analysis. Valve thromboses, and emboli are less reported with bioprosthetic valve (RR=6.52; 95% CI: 3.00, 14. 15; p<0.00001) and (RR=2.25; 95% CI: 1.14, 4.46; p= 0.02) respectively. There was no statistically significant difference between valve types as regards to bleeding, heart block, low cardiac output, valve failure, infective endocarditis, stroke, and renal failure.Conclusion: The type of the tricuspid valve prosthesis should be chosen based on patient's characteristics but occa-sionally it's equivocal, that's when the bioprosthetic valve should be preferred because of its less morbidity.

Mechanical versus bioprosthetic valves in patients on dialysis

The aim of this study is to evaluate the outcomes of bioprosthetic versus mechanical valves in patients on dialysis. All patients who underwent aortic (AVR) or mitral valve replacement (MVR) at a single institution from 2011-2017 were reviewed. Primary stratification was bioprosthetic versus mechanical valves. The primary outcome was all-cause mortality. Secondary outcomes included hospital readmission, valve reoperation rates and bleeding events. Kaplan-Meier curves were generated and Cox proportional hazards regression models were used for risk-adjustment. During the study period, 3,969 patients underwent AVR or MVR, of which 97 (2.4%) were on dialysis. In dialysis patients, unadjusted 30-day mortality was comparable between bioprosthetic (12.7%) versus mechanical (5.9%) valves (P=0.31). However, the bioprosthetic group had higher rates of 1-year (40.3% versus 15.2%; P=0.03) and 5-year mortality (67.9% versus 60.7%; P=0.02). Most patients were readmitted within 5 years with no differences between the groups (bioprosthetic 80.3% versus mechanical 100%; P=0.57). There were no valve reoperations in either group at 5 years. The 5-year readmission rate was higher in the mechanical cohort (10.5% versus 53.8%; P=0.05). Risk-adjusted analysis confirmed these findings, where mechanical valves were independently associated with reduced mortality at 1-year and 5-years. Despite the limited life expectancy of patients on dialysis, mechanical valves have an intermediate term mortality benefit compared to bioprosthetic valves. This comes at the expense of a higher rate of readmission for bleeding. Although valve choice should consider multiple factors, these data suggest that mechanical valve usage in dialysis patients is reasonable.

Clinical Characteristics, Procedural Factors, and Outcomes of Percutaneous Coronary Intervention in Patients With Mechanical and Bioprosthetic Heart Valves

There is scarcity of evidence regarding antiplatelet and anticoagulant therapy in patients with prosthetic valves undergoing percutaneous coronary intervention (PCI). Our goal was to compare clinical outcomes between patients with mechanical or bioprosthetic valves undergoing PCI. The study population comprised patients with either a bioprosthetic or mechanical heart valve in the aortic and/or mitral position undergoing PCI between January 2003 and July 2017. Demographics, admission, and discharge medications as well as procedural details were documented. Outcomes were postprocedural bleeding, length of stay, and in-hospital deaths. Of 211 patients, we identified 119 and 92 patients with a bioprosthetic or mechanical valve, respectively. Mean age was 75 ± 9 years and 66 ± 12 years in bioprosthetic and mechanical valve patients, respectively. Bare-metal stents were used in 18.2% and 30.1% of bioprosthetic and mechanical valve patients, respectively. Major bleeding was documented in 0.8% and 6.5% of bioprosthetic and mechanical valve patients, respectively (p = 0.04). Use of triple therapy (aspirin AND clopidogrel AND oral vitamin K antagonist) was significantly lower in bioprosthetic valve patients compared with mechanical valve patients (12% vs 68%, p <0.001). Our study shows variation in periprocedural anticoagulation and/or antiplatelet choice exists in this population. Patients with mechanical valves experienced higher rates of major bleeding compared with patients with bioprosthetic valves, which could be due to concomitant anticoagulation and dual antiplatelet therapy.

Risk of reoperation in bioprosthetic valve patients with indication for long-term anticoagulation. Results from the observational retrospective multicentre PLECTRUM study

ObjectiveSeveral factors should be considered when a prosthetic heart valve, bioprosthetic valve (BV) or mechanical valve is to be implanted: thrombogenicity, life expectancy and the risk of reoperation.MethodsWe conducted an...

Propensity Score Matched Analysis of Mechanical vs. Bioprosthetic Valve Replacement in Patients With Previous Stroke.

This study compared the long-term outcomes of prosthetic heart valve replacement with mechanical or bioprosthetic valves in patients with prior stroke.Methods and Results:In total, 1,984 patients with previous stroke who had received valve replacement between 2000 and 2011 were identified using the Taiwan National Health Insurance Research Database. Propensity score matching analysis was used. Ultimately, 547 patients were extracted from each group and were eligible for analysis. On survival analysis, the risks of all-cause mortality and recurrence of stroke were similar. The incidence of major bleeding was greater in the mechanical valve group than in the bioprosthetic valve group (P=0.040), whereas no difference was observed in re-do valve surgery. On subgroup analysis, the bioprosthetic valve was favored for older age (≥60 years) and previous gastrointestinal (GI) bleeding patients. The mechanical valve, however, was favored for younger patients (<60 years). In patients with previous stroke, bioprosthetic valves had a lower incidence of complications connected to major bleeding than did the mechanical valves. Survival and stroke recurrence rates, however, did not differ between the 2 groups. We recommend bioprosthetic valves for patients >60 years or who have a history of GI bleeding.

Valve in valve transcatheter aortic valve implantation (ViV-TAVI) versus redo-Surgical aortic valve replacement (redo-SAVR): A systematic review and meta-analysis.

Bioprosthetic (BP) valves have been increasingly used for aortic valve replacement over the last decade. Due to their limited durability, patients presenting with failed BP valves are rising. Valve in Valve - Transcatheter Aortic Valve Implantation (ViV-TAVI) emerged as an alternative to the gold standard redo-Surgical Aortic Valve Replacement (redo-SAVR). However, the utility of ViV-TAVI is poorly understood. A systematic electronic search of the scientific literature was done in PubMed, EMBASE, SCOPUS, Google Scholar, and ClinicalTrials.gov. Only studies which compared the safety and efficacy of ViV-TAVI and redo-SAVR head to head in failed BP valves were included. Six observational studies were eligible and included 594 patients, of whom 255 underwent ViV- TAVI and 339 underwent redo-SAVR. There was no significant difference between ViV-TAVI and redo- SAVR for procedural, 30 day and 1 year mortality rates. ViV-TAVI was associated with lower risk of permanent pacemaker implantation (PPI) (OR: 0.43, CI: 0.21-0.89; P = 0.02) and a trend toward increased risk of paravalvular leak (PVL) (OR: 5.45, CI: 0.94-31.58; P = 0.06). There was no significant difference for stroke, major bleeding, vascular complications and postprocedural aortic valvular gradients more than 20 mm-hg. Our results reiterate the safety and feasibility of ViV-TAVI for failed aortic BP valves in patients deemed to be at high risk for surgery. VIV-TAVI was associated with lower risk of permanent pacemaker implantation with a trend toward increased risk of paravalvular leak.

Direct oral anticoagulant use in nonvalvular atrial fibrillation with valvular heart disease: a systematic review.

Direct oral anticoagulants (DOACs) are indicated for stroke prevention in patients with nonvalvular atrial fibrillation (NVAF), which, according to the American College of Cardiology/American Heart Association/Heart Rhythm Society atrial fibrillation (AF) guidelines, excludes patients with rheumatic mitral stenosis, a mechanical or bioprosthetic heart valve, or mitral valve repair. However, the data regarding use of DOACs in AF patients with other types of valvular heart disease (VHD) are unclear. We aimed to summarize and evaluate the literature regarding the safety and efficacy of DOAC use in NVAF patients with other types of VHD. After an extensive literature search, a total of 1 prospective controlled trial, 4 subanalyses, and 1 abstract were identified. Efficacy of the DOAC agents in NVAF patients with VHD mirrored the overall trial results. Bleeding risk was significantly increased in VHD patients treated with rivaroxaban, but not for dabigatran or apixaban. Of the bioprosthetic valve patients enrolled in the Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation (ARISTOTLE) trial, no safety or efficacy concerns were identified. In conclusion, subanalyses of DOAC landmark AF trials revealed that dabigatran, rivaroxaban, and apixaban may be safely used in AF patients with certain types of VHD: aortic stenosis, aortic regurgitation, and mitral regurgitation. More evidence is needed before routinely recommending these agents for patients with bioprosthetic valves or mild mitral stenosis. Patients with moderate to severe mitral stenosis or mechanical valves should continue to receive warfarin, as these patients were excluded from all landmark AF trials.

Prognosis after surgical replacement with a bioprosthetic aortic valve in patients with severe symptomatic aortic stenosis: systematic review of observational studies

Objective To determine the frequency of survival, stroke, atrial fibrillation, structural valve deterioration, and length of hospital stay after surgical replacement of an aortic valve (SAVR) with a bioprosthetic valve...

Early Hemodynamic Performance of the Trifecta Bioprosthetic Valve in Patients With Aortic Valve Disease

The Trifecta valve (St Jude Medical) is a novel supra-annular aortic bioprosthesis designed to improve hemodynamic performance. We hypothesized that the Trifecta may offer better hemodynamic performance in Japanese patients, in whom the annulus is smaller, compared with Western populations. We compared the early results of hemodynamic performance between the Trifecta and the Magna (Edwards Lifescience) valves at our institution. The Trifecta was implanted in 33 patients and the Magna was implanted in 41 patients who had aortic valve disease. Postoperative echocardiography was performed just before discharge, and the mean pressure gradient (MPG), effective orifice area (EOA) index and energy loss coefficient (ELCo) index were compared between the 2 groups. The average prosthesis size was similar between the 2 groups (21.1 vs. 21.3mm). The Trifecta group had a significantly lower MPG (P=0.001) and larger EOA index and ELCo index than the Magna group (P<0.001 for both). On multivariate linear regression analysis, use of the Trifecta was the strongest independent determinant of postoperative MPG, EOA and ELCo index. The Trifecta valve provides excellent early postoperative hemodynamic performance in Japanese patients. Patients with a small annulus size relative to body size may benefit more from the Trifecta in terms of postoperative hemodynamic performance.

Fate of transcatheter valve-in-valve implantation and redo cardiac surgery for failing bioprosthetic valves in patients with high operative risk

Purpose: Transcatheter valve-in-valve implantation is a feasible treatment for patients with failing cardiac bioprostheses who have increased operative risk. The study aimed to compare the outcome of this therapy with redo cardiac surgery. Methods: The study compared the survival of patients with failing cardiac bioprostheses or mitral valve annuloplasty treated with transcatheter valve-in-valve with high risk patients who underwent redo cardiac surgery in a single institution. Results: Overall 16 patients (age 80±2 years, 25% male) underwent transcatheter valve-in-valve procedure and 16 patients (age 70±1 years, 50% male) redo valve surgery. The valve in valve treated group was comparable with surgery treated group with respect to logistic Euroscore (34.1±14.6% vs. 30.8±20.3% p=0.605), New York Heart Association functional class (≥III: 9 (56%) vs. ≥III 7 (44%), p=1.000) and left ventricular ejection fraction (37% (27-52) vs. 40% (26-57), p=0.724). After a median follow up of 21 (7-44) months, overall 10 (30%) patients died. One-year survival of patients treated with valve-in-valve did not differ from those treated with redo surgery (75% vs. 72%, respectively; log-rank p=0.939). Conclusion: Patients with failing cardiac bioprostheses and high operative risk treated with transcatheter valve-in-valve have similar survival compared to high risk patients undergoing redo cardiac surgery.

Early Postoperative Bioprosthetic Valve Calcification

Bioprosthetic valves are implanted in elderly patients with good follow up results. The degeneration of these valves is slow and there are multiple aetiologies for that. It is unclear whether renal failure accelerates the degeneration of bioprosthetic valves in patients with normal calcium levels. We present a case with tissue valve degeneration 16 months postoperatively in a patient with renal failure.

EComment. Are mechanical valves better than bioprostheses in patients on dialysis?

We read with great interest the article by Pai et al. regarding the best valve substitute in patients on dialysis [1]. They included in the results of their research, seven retrospective studies and one meta-analysis. However, we found 4 other relevant articles investigating the same problem. In order to be exhaustive, we will summarize the relevant results of these studies and highlight the safety of implanting bioprosthesis in patients on chronic dialysis. The standard of valve selection has changed over time. It has long been believed that tissue valves undergo premature degeneration due to the derangements in calcium metabolism in patients with end-stage renal disease. This is based on largely anecdotal case reports using first generation bioprostheses. In 1998, ACC/AHA guidelines recommended the use of mechanical valves in patients on dialysis. Accumulating data supporting the very low incidence of rapid tissue valve degeneration in dialysis patients had been taken into consideration, and the latest ACC/AHA practice guidelines do not specify the best choice for valve replacement in dialysis patients. Only four cases of structural valve deterioration (SVD) requiring reoperation were identified from the meta-analysis [1], ranging from 10 to 96 months after the initial valve replacement surgery. However, conclusions on the long-term performance of tissue valves in this patient population cannot be drawn. Bleeding was the most common valve-related complication, and represented a major drawback of mechanical valves. Lucke et al. [2] reviewed 19 consecutive patients with end-stage renal disease from a single institution who had undergone aortic, mitral or aorto-mitral valve replacement, 9 had a bioprosthetic valve and 10 a mechanical valve. Mechanical valve patients had a significantly higher rate of postoperative cerebrovascular events or bleeding complications. No subsequent reoperations were required for biological valve failure. The overall estimated Kaplan-Meier survival was 42% ± 14% at 60 months. Kaplon et al. [3] from The Cleveland Clinic Foundation, found comparable results for both types of valves when reviewing 42 patients on preoperative dialysis undergoing valve replacements. Seventeen patients received mechanical valves and 25 received bioprosthesis. Four patients with a bioprosthesis required reoperation, one of whom experienced mitral bioprosthesis degeneration. Prosthetic valve-related complications and survival were similar for both mechanical and bioprosthetic valves. Toole et al. [4] reviewed 50 dialysis patients undergoing left-sided valve replacement. The tissue valve group had significantly higher Kaplan-Meier freedom from valve-related morbidity and mortality at three years. Freedom from reoperation was not significantly different. Umezu et al. [5] analyzed data from 63 consecutive dialysis patients who underwent valvular surgery. The mechanical group had a higher rate of bleeding events. There was no case of SVD up to the 5-year follow-up. However, both mechanical and bioprosthetic valve patients had similar survival and event-free rates. It can be concluded that dialysis patients after cardiac valve replacement suffer poor mid- and long-term survival. Therefore, surgeons should not hesitate to implant bioprosthetic valves because SVD will be uncommon in this patient population. Prosthesis selection should be based on the same criteria used for non-dialysis patients. Conflict of Interest: None declared

Ten-year comparison of pericardial tissue valves versus mechanical prostheses for aortic valve replacement in patients younger than 60 years of age

Aortic valve replacement using a tissue valve is controversial for patients younger than 60 years old. The long-term survival in this age group, the expected event rates during long-term follow-up, and valve-related complications are not clearly determined. From January 2000 to December 2009, overall survival, valve-related events, and echocardiographic outcomes were analyzed in all patients younger than 60 years of age, who underwent biologic aortic valve replacement. Patients who received a Perimount Carpentier-Edwards pericardial tissue valve (n = 103) were selected and compared with a propensity matched group of 103 patients who received aortic valve replacement using a mechanical bileaflet valve. The mean follow-up was 33 ± 24 months (range, 2-120), and the mean age at implantation was 50.6 ± 8.8 years (bioprosthesis, 55 ± 8.9 years; mechanical valve, 50 ± 8.6 years; P = .03). Survival was significantly reduced in patients after biologic aortic valve replacement (90.3% vs 98%; P = .038). Freedom from all valve-related complications (bioprosthesis, 54.5%; mechanical valve, 51.6%; P = NS) and freedom from reoperation (bioprostheses, 100%; mechanical valve, 98%; P = NS) were comparable in both groups. The average transvalvular mean (11.2 ± 4.2 mm Hg vs 10.5 ± 6.0 mm Hg, P = .05) and peak (19.9 ± 6.7 mm Hg vs 16.7 ± 8.0 mm Hg, P = .03) gradients were greater after biologic aortic valve replacement. Regression of the left ventricular mass index was more pronounced after mechanical valve replacement (118.5 ± 24.9 g/m(2) vs 126.5 ± 38.5 g/m(2); P = NS). The echocardiographic patient-prosthesis mismatch was greater at follow-up after biological aortic valve replacement (0.876 ± 0.2 cm(2)/m(2) vs 1.11 ± 0.4 cm(2)/m(2); P = .01). Oral anticoagulation was a protective factor for survival among the bioprosthetic valve patients (P = .024). In the present limited cohort of patients younger than 60 years old, biologic aortic valve replacement was associated with reduced mid-term survival compared with survival after mechanical aortic valve replacement. Despite similar valve-related event rates in both groups, the better hemodynamic performance of the mechanical valves and/or protective effect of oral anticoagulation seemed to improve the outcome. The transcatheter valve-in-valve intervention as potential treatment of tissue valve degeneration should not be considered the sole bailout strategy for younger patients because no evidence is available that this would improve the outcome.