Concomitant Tricuspid Valve Repair or Replacement During Left Ventricular Assist Device Implant Demonstrates Comparable Outcomes in the Long Term

Abstract Introduction: Severe tricuspid regurgitation (TR) is present in nearly half the patients undergoing implant of a left ventricular assist device (LVAD) and its correction confers better long‐term outcome. Aim: To compare the early and late results of tricuspid valve repair (TVrpr) or replacement (TVR) with LVAD implant. Patient and Methods: Sixty‐four from a cohort of 126 patients had a concomitant tricuspid valve procedure; 48 (75%) underwent a TVrpr whereas 16 (25%) had TVR. All preoperative hemodynamic parameters including the mean TR grade (TVrpr; 3.6 vs. TVR; 3.7) were comparable (p = 0.7). The mean TR grade was 1.6 ± 1.5 for the remaining 62 patients who did not have a concomitant tricuspid valve procedure, with 4/62 (6%) having severe TR (p < 0.0001). Results: Cardiopulmonary bypass time was longer for patients undergoing TVR (p = 0.01). There was a significant reduction in right atrial pressure for the entire cohort (p < 0.01) and the postoperative right atrial pressure was not statistically different between TVrpr (13.6 ± 4.6) and TVR (11.6 ± 4.3; p = 0.6. Postoperative intensive care unit stay was comparable as was the duration of inotropic support (p = 0.5) or need for temporary right ventricular mechanical support. In‐hospital mortality (12%) was not different between groups. The mean time for LVAD support was 12.3 ± 9.71 months and the last transthoracic echocardiographic examination was performed at mean intervals of 13.8 ± 10.8 months (TVrpr) and 11.8 ± 7.6 months (TVR; p = 0.47). Reduction in TR grade was similar between groups (p = 0.27). Late mortality (p = 1.00) was comparable in both groups. Using log‐rank analysis, there was no significant difference in the estimated survival between TVrpr and TVR (p = 0.88). Conclusion: TVrpr repair at the time of LVAD implant is effective in correcting TR even at the end of one year of follow‐up. The choice to repair or replace does not affect the clinical outcome. (J Card Surg 2012;27:760‐766)     

Intermediate-term outcomes of aortic valve replacement with bioprosthetic or mechanical valves in patients on hemodialysis

ObjectiveTo investigate the influence of choice of prosthesis (bioprosthetic valves or mechanical valves) on intermediate-term outcomes in patients on hemodialysis undergoing aortic valve replacement (AVR).MethodsA multi-institutional retrospective cohort study was conducted in 18 Japanese centers. All adult patients on chronic hemodialysis who underwent AVR from 2008 and 2015 were included (n = 491). The early and late results were compared between groups. The hazard ratios were calculated using Cox regression and Fine–Gray models with adjustment for propensity score based on 41 confounders. The mean follow-up period was 2.5 ± 2.1 years (up to 8.3 years) with 98% completeness.ResultsThere were 323 patients who received a bioprosthetic valve (group B), and 168 patients who received a mechanical valve (group M). There was no significant difference for in-hospital death rate between groups (group B: 12.1%; group M: 8.9%; P = .29). The overall survival rate at 5 years after surgery was 39.3% in group B and 50.4% in group M (P = .42). Freedom from reoperation at 5 years was 97.1% in group B and 97.8% in group M (P = .88). On propensity-score adjusted analyses, there were no significant differences in overall survival between groups.ConclusionsThere were no significant differences in overall survival between bioprosthetic valves and mechanical valves in patients on hemodialysis undergoing AVR.     

Tricuspid valve replacement: an analysis of 25 years of experience at a single center

BACKGROUND: Tricuspid valve replacement is seldom used in clinical practice, but the choice between mechanical and biologic prostheses remains controversial. METHODS: Between 1977 and 2002, 97 patients underwent tricuspid valve replacement and were followed at the Montreal Heart Institute Valve Clinic. Patients underwent replacement with bioprostheses (n = 82) and mechanical valves (n = 15). RESULTS: Patients with bioprosthetic tricuspid replacements averaged 53 +/- 13 years of age compared with 48 +/- 11 years in those with tricuspid mechanical valve replacements (p = 0.2). Isolated tricuspid valve replacement was performed in 11 patients (73%) in the mechanical valve group compared with 31 patients (38%. p = 0.01) in the bioprosthetic replacement group. In patients undergoing bioprosthetic tricuspid replacement, 51 (62%) underwent multiple associated valve replacements. The 5-year survival after tricuspid replacement averaged 60% +/- 13% in the mechanical valve group and 56% +/- 6% in the biologic replacement group (p = 0.8). The 5-year freedom rate from tricuspid valve reoperation averaged 91% +/- 9% in patients with mechanical valves and 97% +/- 3% in those with biologic valves (p = 0.2). CONCLUSIONS; Patient survival after tricuspid valve replacement is suboptimal but related to the clinical condition at operation. The use of biologic prostheses for tricuspid valve replacement remains a good option in young patients because of limited life expectancy unrelated to the type of tricuspid prostheses at long-term follow-up.     

Mitral Valve Replacement with the Hancock Bioprosthesis: Five- to Ten-Year Follow-up

One hundred eleven patients undergoing mitral valve replacement, either alone (56) or in conjunction with another type of prosthetic valve, prior to 1975 were evaluated. Hospital mortality was 9.9%. Cumulative follow-up is 505 patient-years (mean, 5.4 years). Seventy patients have been followed between 5 and 10 years. Late mortality for mitral valve replacement alone is 4.3 ± 1.3% per patient-year; actuarial survival is 82 ± 6% at 5 years and 65 ± 11% at 10 years. The incidence of emboli was 3.3 ± 0.9% per patient-year for all patients with bioprostheses (62) and 4.2 ± 1.7% per patient-year for bioprostheses and concomitant mechanical aortic valves (32). In patients with only bioprostheses, two of twelve emboli occurred within the first 6 postoperative months and there were three fatal cerebral emboli (0.8 + 0.5% per patient-year). The incidence of hemorrhagic complications is 4.9 ± 1.9% for anticoagulated patients with bioprostheses and mechanical aortic valves; one hemorrhage was fatal (0.7 ± 0.7% per patient-year). Intrinsic mitral bioprosthesis failure occurred in 10 patients; 2 died. Five patients had valve failure secondary to perivalvular regurgitation (3) or endocarditis (2). Actuarial late survival free from intrinsic mitral bioprosthetic failure was 99 ± 1% at 5 years, 92 ± 4% at 7 years, 70 ± 12% at 9 years, and 61 ± 13% at 10 years.It is unknown at the present time whether the long-term risk of late intrinsic valve failure and reoperation will outweigh the low incidence of emboli and avoidance of anticoagulant-related hemorrhage. Until further information becomes available, the Hancock bioprosthesis is used for mitral valve replacement only in patients older than 60 years or in patients with contraindications for anticoagulant therapy.     

Severe tricuspid regurgitation after mitral valve surgery: the risk factors and results of the aggressive application of prophylactic tricuspid valve repair

Purpose

This study aimed to examine the risk factors for severe postoperative tricuspid regurgitation (TR) in patients undergoing mitral valve surgery. We also studied the effects of prophylactic tricuspid valve repair (TVR) on severe postoperative TR.

Methods

We retrospectively studied 125 patients without severe TR who underwent mitral valve surgery from 1987 to 2006. Patients did not undergo TVR before 1998 (the early period, n = 54). In 1998 (the late period, n = 71), patients with a preoperative tricuspid annular diameter of ≥35 mm underwent TVR using an annuloplasty ring (n = 52).

Results

In the analysis of the early period, the rates of freedom from severe TR at 10 and 20 years after surgery were 76 and 59 %, respectively. A multivariate analysis identified moderate preoperative TR as a significant risk factor for severe TR. In the late period, none of the 52 patients who underwent TVR developed severe TR. However, 4/19 patients who did not undergo TVR developed severe TR, and all of these four patients had a preoperative tricuspid annular diameter of ≤35 mm.

Conclusions

Moderate preoperative TR is a significant risk factor for severe postoperative TR in patients undergoing mitral valve surgery. The aggressive application of TVR can prevent severe postoperative TR; however, tricuspid annular dilatation might not be a good indicator for TVR.

     

Valve-on-valve technique for replacement of degenerated tricuspid bioprosthetic valve without explantation

A 73-year-old woman admitted to our hospital with shortness of breath and edema of the lower extremities was diagnosed with right ventricular failure stemming from tricuspid valve regurgitation. She had undergone mitral valve replacement (MVR) with a mechanical valve at the age of 51, and reoperative MVR with mechanical valve, tricuspid valve replacement (TVR) with bioprosthetic valve, and pacemaker implantation at the age of 63. Reoperative TVR was performed when the patient failed to respond to drug therapy. A beating heart cardiopulmonary bypass procedure was performed in which only the bioprosthetic valve leaflet was excised, and reoperative TVR was performed with a 27-mm OptiForm^TM mechanical mitral valve (Sulzer Carbomedics Inc., Austin, TX, USA) by the valve-on-valve technique. The operative course was uneventful. The technique used here appears to be an effective approach to reoperative TVR, in this instance making it possible to avoid the risks associated with excision of the old prosthesis.     

Long-term results of bioprosthetic tricuspid valve replacement: an analysis of 25 years of experience

Background

Current knowledge in long-term results of tricuspid valve replacement is limited. Present study reviews our experience from a consecutive series.

Methods

We retrospectively studied the early and late results of 32 consecutive patients (7 male and 25 female; mean age 60.2 ± 18.1 years) undergoing bioprosthetic tricuspid valve replacement between 1985 and 2010. The etiology is rheumatic in 38 %, congenital in 3 %, endocarditis in 9 %, and functional in 50 %. Patients underwent isolated valve replacement. The remaining underwent combined aortic and tricuspid (n = 5, 16 %), mitral tricuspid (n = 15, 47 %), and aortic, mitral, and tricuspid (n = 1, 3 %) valve replacement. Preoperative liver dysfunction was evaluated using Model for End-stage Liver Disease (MELD) score. Mean follow-up was 5.6 ± 6.8 years (ranging from 0 to 25.0 years).

Results

Hospital mortality was 19 %. On univariate logistic regression analysis, NYHA class IV (p = 0.039, odds ratio 11.3, 95 % confidence interval 1.2–112.5), MELD score (>10) (p = 0.011, odds ratio 21.0, 95 % confidence interval 12.0–222.0) and congestive liver (p = 0.05, odds ratio 9.4, 95 % confidence interval 1.0–93.5) were incremental risk factors for hospital death. The 15- and 25-year actuarial survival were 56.5 ± 10.3 % and 45 ± 13.0 %, respectively. Multivariate analysis using Cox proportional hazard model showed MELD score (p = 0.024, hazard ratio 7.0, 95 % confidence interval 2.1–23.9) and postoperative pulmonary hypertension (p = 0.012, hazard ratio 4.4, 95 % confidence interval 1.4–14.1) were significantly associated with decreased survival. At 15 years, freedom rates from tricuspid valve reoperation, anticoagulation-related bleeding, and valve related events were 85.7 ± 13.2 %,95.7 ± 4.3 % and 81.8 ± 13.2 %, respectively. The linearized incidence of structural valve deterioration was 0.50 %/patient-year, anticoagulation-related bleeding was 0.94 %/patient-year, and valve-related events were 1.52 %/patient-year.

Conclusion

Preoperative hepatic congestion and liver dysfunction which were indicated by the MELD score >10 were associated with poor outcome for patients undergoing tricuspid valve replacement. The MELD score is useful to predict the morality among these patients.     

Valve replacement in the right side of the heart in children: long-term follow-up

Twenty-five patients (16 male, 9 female) underwent right-sided valve replacement (10 pulmonary valve replacement, 14 tricuspid valve replacement, 3 tricuspid plus pulmonary valve replacement, and 2 replacements of a single atrioventricular valve) at the University of Nebraska Medical Center from June 1977 to December 1986. Twenty-one patients (84%) are long-term survivors with 2,035 months follow-up (range, 41 to 143 months; mean, 96.9 months). Twenty-three Carpentier-Edwards bioprosthetic valves, one Ionescu-Shiley bioprosthetic valve, and nine St. Jude Medical valves were inserted. Follow-up of 17 patients with a Carpentier-Edwards valve ranged from 5 years 9 months to 11 years 9 months (mean, 8 years 11 months). To date there has been one reoperation after 3 years 4 months in this group. One patient who received an Ionescu-Shiley bioprosthesis required re-replacement at 20 months after operation. Three of 4 patients who received St. Jude mechanical valves and are long-term survivors have required replacement after 36 to 56 months. We conclude that the Carpentier-Edwards bioprosthetic valve is a viable option in the right side of the heart in the young age group when annular size is adequate to accommodate an appropriate bioprosthesis.     

Prognostic Impact and Late Evolution of Untreated Moderate (2/4+) Functional Tricuspid Regurgitation in Patients Undergoing Aortic Valve Replacement

Objectives

The aim of the present study was to evaluate the prognostic impact and late evolution of associated tricuspid regurgitation (TR) 2/4+ after aortic valve replacement (AVR).

Methods

We evaluated 61 patients who underwent AVR between 2003 and 2012 (35 for aortic stenosis [AS], 26 for aortic regurgitation [AR]) with associated untreated TR 2/4+. Patients with concomitant mitral disease were excluded. Median follow‐up was 3.2 years. Serial echocardiographic and clinical data were collected and analyzed.

Results

Mean age was 65 ± 13 years; 26% of the patients were in NYHA class III–IV. Left ventricular ejection fraction was 53 ± 11%. Comorbidity included: chronic obstructive pulmonary disease in 5%, chronic renal failure in 13%, coronary artery disease in 20%, history of stroke/TIA in 8%. Thirty‐day mortality was 1.6%. Overall actuarial survival was 83 ± 6% at 6.5 years, with a freedom from cardiac death of 90 ± 5%. Freedom from TR ≥3+ was 86 ± 6% at 6.5 years. At last follow‐up, 82% of the patients had TR 0–1/4+, 9% had TR 2/4+, 4.5% had TR 3/4+ and 4.5% had TR 4/4+. Occurrence of TR ≥ 3+ at follow‐up was associated with increased cardiac mortality (HR 10.5; p = 0.009).

Conclusions

preoperative untreated TR 2/4+ improves or remains stable in the majority of patients. The poor outcomes associated with TR > 2+ suggest the need for better methods to identify subjects at risk for TR progression. doi: 10.1111/jocs.12656 (J Card Surg 2016;31:9–14)     

Hospital readmission rates are similar between patients with mechanical versus bioprosthetic aortic valves

Background

The aim of this study was to evaluate hospital readmission rates and clinical outcomes between bioprosthetic (bAVR) and mechanical (mAVR) aortic valve replacements (AVR).

Methods

Adults aged 50 years or older undergoing isolated or concomitant AVR between 2011 and 2017 were included. The primary outcome was 5‐year hospital readmission. Multivariable logistic regression analysis was used to evaluate the risk‐adjusted impact of bAVR versus mAVR on outcomes.

Results

A total of 2981 patients were included: 406 (14%) mAVR and 2575 (86%) bAVR. Mean follow‐up was 2.9 ± 1.9 years. Operative mortality was comparable (4% bAVR vs 3% mAVR; P = 0.30). There was no risk‐adjusted difference in 30‐day (hazard ratio [HR] 1.32, P = 0.46), 1‐year (HR 1.17, P = 0.52), or 5‐year mortality (HR 0.99, P = 0.93). Aortic valve 5‐year reoperation rates were comparable (1%, P = 0.32). Risk‐adjusted hospital readmissions were similar at 30 days (14% vs 15%; P = 0.63), 1 year (30% vs 27%; P = 0.43), and 5 years (55% vs 53%; P = 0.83) in the bAVR and mAVR groups, respectively. Similar findings were demonstrated when evaluating readmissions for bleeding (5‐year readmission: 8% bAVR vs 10% mAVR; P = 0.36).

Conclusions

In this analysis of over 2900 AVRs, readmissions within 5 years were comparable between groups at approximately 50%, with patients being at highest risk in the early postdischarge period. Readmissions for bleeding constituted a minority of all readmissions for both cohorts.     

Bioprosthetic Versus Mechanical Valve Replacement in Patients with Infective Endocarditis

During the 5-year period, 1979-1984, at the Texas Heart Institute, 4,598 patients underwent cardiac valve replacement procedures of which 185 were for acute infective endocarditis. Staphylococcus and streptococcus accounted for 80% of the cases and congestive heart failure was a leading indication in 63%. The purpose of this article is to evaluate the recurrence of endocarditis dependent upon whether the patient had an Ionescu-Shiley bioprosthetic pericardial valve or a mechanical valve (St. Jude Medical). Actuarial freedom from both early and late reoperation was higher for prosthetic valves than bioprosthetic valve patients. We conclude that mechanical valves are the valves of choice in acute infective endocarditis which apparently is the results of less biologic tissue available for exposure to infection by the offending organisms.     

Impact of intraoperative transesophageal echocardiography in patients undergoing valve replacement

Background

The role of intraoperative transesophageal echocardiography (IOTEE) in valve replacement surgery is not well established. The aim of this study was to explore the impact of immediate postpump IOTEE in valve replacement surgery at a single tertiary medical center.

Methods

The departmental database was screened for valve replacement operations (mechanical or bioprosthetic valves) performed during a 55-month period that were succeeded by immediate postpump IOTEE. Data was gathered regarding the impact of IOTEE on the immediate postoperative course.

Results

The study group included 417 patients (44.8% male, 55.2% female, age 65.2 ± 13.9 years). Prepump IOTEE was performed in 352 patients (84.4%). A single valve was replaced in 336 patients (80.6%) and two or more valves were replaced in 81 patients (19.4%). Overall 501 valves were inserted: mitral, 237 (131 mechanical, 106 biological); aortic, 221 (89 mechanical, 132 biological); tricuspid, 43 (2 mechanical, 41 biological). Unexpected pathologic echocardiographic findings on postpump IOTEE necessitated immediate surgical correction in 15 patients (3.6%): perivalvular leak in 8 patients (4 mitral, 4 aortic), immobilized leaflet in 4 patients (3 mitral, 1 tricuspid), coronary obstruction by an aortic bioprosthesis in 2 patients, and incompetent xenograft in 1 patient. Prolonged removal of air was necessary in 45 patients (10.8%). In 47 patients (11.3%) the postpump IOTEE contributed to the evaluation of difficult weaning from the bypass pump and to its appropriate therapeutic management (volume expansion, inotropic agents, vasodilators, or mechanical assistance).

Conclusions

Immediate postpump IOTEE is an important diagnostic and therapeutic role in valve replacement surgery and should be widely implemented.     

Risk of Reoperative Valve Replacement for Failed Mitral and Aortic Bioprostheses

Background. One factor influencing the choice of mechanical versus bioprosthetic valves is reoperation for bioprosthetic valve failure. To define its operative risk, we reviewed our results with valve reoperation for bioprosthetic valve failure.

Methods. Records of 400 consecutive patients having reoperative mitral, aortic, or mitral and aortic bioprosthetic valve replacement from January 1985 to March 1997 were reviewed.

Results. Reoperations were for failed bioprosthetic mitral valves in 219 patients, failed aortic valves in 153 patients, and failed aortic and mitral valves in 28 patients. Including 26 operations (6%) for acute endocarditis, 153 operations (38%) were nonelective. One hundred nine patients (27%) had other valves repaired or replaced, and 72 (18%) had coronary bypass grafting. The incidence of death in the mitral, aortic, and double-valve groups was respectively, 15 (6.8%), 12 (7.8%), and 4 (14.3%); and the incidence of prolonged postoperative hospital stay (>14 days) was, respectively, 57 (26.0%), 41 (26.8%), and 8 (28.6%). Only 7 of 147 patients (4.8%) having elective, isolated, first-time valve reoperation died. Multivariable predictors (p < 0.05) of hospital death were age greater than 65 years, male sex, renal insufficiency, and nonelective operation; and predictors of prolonged stay were acute endocarditis, renal insufficiency, any concurrent cardiac operation, and elevated pulmonary artery systolic pressure.

Conclusions. Reoperative bioprosthetic valve replacement can be performed with acceptable mortality and hospital stay. The best results are achieved with elective valve replacement, without concurrent cardiac procedures.     

Long‐term outcomes after mechanical aortic valve replacement with aortic root enlargement in adolescents

Background

Deciding which prosthetic aortic valve to choose is difficult in adolescents who have not yet met their full growth potential. The aim of this study was to assess long‐term outcomes following mechanical aortic valve replacement with aortic root enlargement in adolescents.

Methods

Between September 1997 and December 2006, 58 consecutive adolescents (49 male, 9 female, median age 15.5, range 13 to 17 years) underwent mechanical aortic valve replacement with aortic root enlargement. All patients received long‐term anticoagulation treatment with warfarin, aiming to maintain an international normalized ratio between 2.0 and 2.5. Follow‐up of all patients was closed in December 2015.

Results

The mean size of implanted valves was 20.1 ± 1.3 mm. There were two operative deaths (3.4%) and one late death (1.7%). Mean follow‐up was 11.6 ± 3.3 years (range, 8.5 to 15.8 years). Actuarial survival at 15 years was 94.7 ± 3.2%. No patient required a redo procedure. At the latest clinical evaluation, 47 patients (81.0%) were in New York Heart Association functional class I and 8 (13.8%) were in functional class II. Actuarial freedom from valve‐related complication was 88.1 ± 2.8% at four years. The mean gradient across the aortic mechanical valve on echocardiography was 13.2 ± 6.3 mmHg (range 6 to 38 mmHg).

Conclusions

Mechanical aortic valve replacement with aortic root enlargement remains an excellent treatment option in adolescents with full growth potential. The mortality is very low and all surviving patients resumed normal lifestyles. It represents a good alternative to allografts and bioprostheses in adolescent patients with aortic valve disease.     

Management of tricuspid valve insufficiency. Replacement with Hancock bioprosthesis or suture annuloplasty

Forty-seven patients who underwent tricuspid valve replacement (TVR) or tricuspid annuloplasty (TA) combined with aortic (AVR) or mitral valve replacement (MVR) at Henry Ford Hospital, from 1971 to 1977 are reviewed. Thirty-three patients underwent TVR with a Hancock valve combined with MVR or AVR; hospital mortality was 30% (10 to 33) and was higher at the beginning of the series when smaller valves were used. No valve dysfunction has been seen with mean follow-up time of 36.7 months, ranging from 4 to 60 months. Good functional improvement was accomplished in all patients. Fourteen patients underwent TA; hospital mortality was 21% (3 of 14) with one late mortality (9%); good functional improvement was accomplished in all patients. However, one patient presented 11 months following surgery with tricuspid insufficiency after a period of improvement. For patients with severely deformed valves a large size Hancock valve is recommended. For insufficiency alone tricuspid annuloplasty is recommended.     

Repair of tricuspid valve with pulmonary valve replacement in repaired tetralogy of fallot

Objectives: We aimed to investigate the outcome of tricuspid valve repair (TVR) performed concomitantly with pulmonary valve replacement in repaired tetralogy of Fallot (TOF) patients. Design: This retrospective study included all patients who underwent pulmonary vale replacement from 2000 to 2016 after TOF correction. TVR patient data were compared to those of patients who underwent pulmonary vale replacement alone. Results: Thirty-eight patients were enrolled. The degree of tricuspid regurgitation was significantly decreased after operation in the TVR group. Tricuspid valve annulus and annuloectasia before operation did not vary between groups (21.1?±?6.3 and 41.4% in no TVR vs. 21.3?±?4.8 and 52.6% in TVR). However pre-operative right ventricular volumes were larger in the TVR group. Normal tricuspid valve coaptation (body to body) was observed less frequently in the TVR group than in the other group (52.6% vs. 93.1%, p < .001). Pre-operative tricuspid regurgitation had a linear correlation with right ventricular volume, but not with tricuspid annulus size. Conclusion: Tricuspid annulus diameter decreased significantly regardless of TVR. Abnormal coaptations were observed more in patients group and the degree of pre-operative tricuspid regurgitation was linearly correlated with right ventricular volume rather than tricuspid annulus size.     

Valve replacement in children

Between May 1979 and September 1998, 202 children underwent surgical treatment for valvular heart disease. Of these 23, who ranged in age from 25 days to 15 years, underwent valve replacement, including 1 reoperation. The valve replacement consisted of the aortic valve in 5 patients, the mitral valve in 3, the tricuspid valves in 9, including 5 systemic atrioventricular valves for atrioventricular discordance, the pulmonary valve in 6, 5 bioprostheses and 18 mechanical prostheses. There were 4 operative deaths, 1 hospital death and 3 late deaths. At the 10-years follow-up, the actual survival rate was 67.8%, the event free rate was 76.1% and the freedom from reoperation rate was 86.2%. Valve re-replacement was performed in only 1 patient due to a thrombosed tricuspid valve. These results suggest that there is a small risk of major complications and reoperation in children who undergo valve replacement, whether a bioprosthetic valve or a mechanical valve. The long-term results of younger patients should be followed more closely according to their growth.     

Prosthetic valve replacement in children

Between 1975 and 1998, 27 patients aged 3 months to 14 years underwent replacement of the aortic, mitral, tricuspid, and pulmonary valves. Five different types of prosthetic valves were used; three were mechanical valves and two were bioprosthetic valves. There were 3 hospital deaths. Among the 24 survivors there were 4 late deaths. Arrhythmia requiring pacemaker implantation occurred in 2 cases after AVR and TVR. Thromboembolic events occurred in 3 patients, all with mechanical valves in pulmonary position. Infective endocarditis occurred in 1 patient after PVR with a mechanical valve. No bleeding complication occurred among the patients on a regimen of Coumadin and Dipyridamole. Two patients, both with Hancock bioprosthesis, required a second valve replacement on account of severely calcified changes. Mechanical valves in left side heart had a satisfactory long-term performance. One patient who had undergone MVR for congenital parachute mitral valve received reoperation for growth. A larger sized prosthetic valve should be used at the first replacement, and special procedures including supra-annular positioning or annular augmentation are recommended for MVR or AVR respectively.     

Mechanical valve thrombosis in the tricuspid position--reoperative management of 2 cases

Because valve thrombosis occurred after the tricuspid valve replacement with the mechanical valve, we performed replacement of the mechanical valve with the bovine pericardial valve in two cases. Case 1: The patient, at 13 years old, received open-heart surgery to correct infundibular stenosis. At 23 years of age, decortication and tricuspid valve replacement (TVR) with a phi 31 mm Bj?rk-Shiley valve were performed due to constrictive pericarditis and tricuspid regurgitation developed after the initial operation. Thrombosis of the mechanical valve occurred after the TVR. Treatment with urokinase for the thrombolytic therapy failed to improve the valve opening. Finally 12 years after the TVR, replacement of the mechanical valve with a phi 27 mm Carpentier-Edwards bovine pericardial valve was performed. Case 2: The patient, at 21 years old, received open-heart surgery to close an atrial septal defect. At 40 years of age, mitral and tricuspid valve replacements were performed because regurgitation developed in both valves. The mitral and tricuspid valves were replaced with phi 27 mm and 31 mm St. Jude Medical valves, respectively. Thrombosis of the mechanical valve used for the TVR occurred 2 months after the replacement. The mechanical valve was replaced with a phi 27 mm Carpentier-Edwards bovine pericardial valve. In both cases, subjective symptoms improved and prosthetic valve complications did not occur after re-replacement with the bovine pericardial valve. These cases suggested that for TVR a bovine pericardial valve of sufficient size would be better to select than a mechanical valve.     

Cardiac valvular surgery in dialysis patients: comparison of surgical outcome for mechanical versus bioprosthetic valves

Purpose  There has been a changing preference for bioprosthetic valves over mechanical valves in dialysis patients, but there is still much controversy. We reviewed our 17-year experience and assessed the influence of prosthesis choice. Methods  From 1990 to 2007, a total of 63 consecutive dialysis patients who underwent valvular surgery (64 operations including one reoperation) at our hospital were retrospectively reviewed. The mean age of the patients was 58.3 ± 9.0 years. The reasons for dialysis were glomerulonephritis (n = 32) and diabetes (n = 10). The major preoperative diagnosis was aortic stenosis (n = 44). The surgical procedures included aortic valve replacement (n = 44), mitral valve replacement (n = 7), double valvular replacement (n = 7), and mitral valve repair (n = 5). Prostheses for valve replacement were mechanical valves (n = 37) or bioprosthetic valves (n = 22). Follow-up was accomplished in 95.2%, and the mean follow-up period was 49 months. Results  Actuarial survivals at 1, 5, and 10 years were 85%, 64%, and 45% respectively. Freedom from cardiovascular events at 1 and 5 years was 61% and 41%, respectively. Mechanical valve patients had significantly higher early mortality than bioprosthetic valve patients (P = 0.03). However, both mechanical and bioprosthetic valve patients had similar survival and event-free rates (P = 0.87 and P = 0.27, respectively) in the midterm results. The mechanical group had a higher rate of bleeding events. There was no structural valve deterioration up to the 5-year follow-up. Conclusion  The choice of prosthesis did not influence the surgical outcome except for early mortality. Careful consideration of preventive measures against bleeding is important, and prosthesis selection should be based on the patient’s profile as well as the criteria for nondialysis patients.