Long-term experience with porcine aortic valve xenografts

Between 1971 and 1975, glutaraldehyde-preserved porcine aortic valve xenografts were employed for isolated replacement of the mitral valve (MVR) in 243 patients, replacement of the aortic valve (AVR) in 167 patients, and double valve replacement (AVR and MVR) in 51 patients. Postoperatively, long-term anticoagulation was not routinely given. Operative mortality rates for AVR, MVR, and double valve groups were 7.8, 6.0, and 11.8 per cent, respectively; the majority of early postoperative deaths were associated with concomitant coronary artery disease. No death was attributable to xenograft dysfunction. Follow-up of all patients was obtained. The total duration of follow-up for the MVR group was 347 patient-years, for the AVR GROUP 148 148 patient-years, and for double valve replacement 37 patient-years; maximum follow-up for these three groups was 4.4, 4.0, and 2.4 years, respectively. Actuarial analysis of postoperative survival rates at a common interval of 3 years showed 78 per cent for MVR patients, 91 per cent for AVR patients, and 80 per cent (projected) for patients with double valve replacement (85, 96, and 91 per cent for operative survivors, respectively. At this same interval 92 per cent of MVR patients, 99 per cent of AVR patients, and 93 per cent (projected) of patients with double valve replacement were free of thromboembolic episodes. Altogether, 12 of the total 512 valves implanted exhibited some evidence of dysfunction during the entire period of follow-up evaluation, but in only 2 instances (both mitral) was intrinsic pathological involvement of the xenograft tissue documented. Actuarial analysis of xenograft dysfunction at a common interval of 3 years after operation showed 95 per cent of MVR patients, 98 per cent of AVR patients, and 97 per cent (projected) of patients with double valve replacement to be free of this complication. These data support the use of glutaraldehyde-preserved porcine xenografts as superior bioprostheses that pose a low risk of thromboembolism without anticoagulation. The over-all durability of such valves, within the restriction of a maximum current follow-up interval of 4.4 years, appears comparable to that of currently available mechanical prostheses and justifies continued clinical use.     

Twelve years of experience with the ATS mechanical heart valve prostheses

Objective

The ATS Open Pivot mechanical heart valve has been implanted routinely at our institution since 1999. The objective of this study is to retrospectively analyze our 12-year clinical results with ATS prostheses.

Methods

ATS Open Pivot mechanical valves were implanted in 268 adult patients between May 1999 and August 2010. We selected 259 subjects who could be adequately followed (follow-up rate 96.6?%). Aortic valve replacement was performed in 157 patients, mitral valve replacement (MVR) in 71, and double (aortic and mitral) valve replacements (DVR) in 31. Mean age at the time of implant was 58.8?±?10.6?years. The gender ratio was 128 males/131 females. Mean follow-up was 4.4?±?7.8?years, and the cumulative follow-up was 1144 patient-years (pt-yr).

Results

Early death within 30?days after the operation occurred in 5 (2.5?%) patients. Late death occurred in 27 patients including valve-related deaths in 13. The 10-year survival rate after the operation was 82.7?±?2.9?%. The rate of freedom from valve-related death was 92.2?±?2.2?%. The incidence of valve-related complications was 2.19?%/pt-yr. Of these, the incidence of thromboembolic events and that of bleeding complications were 1.22 and that 0.87?%/pt-yr. The incidence of valve thrombosis was 0.09?%/pt-yr. No structural valve deterioration was observed in any of the three operative procedure groups.

Conclusions

Our 12-year experience with aortic and MVR using the ATS mechanical heart valve demonstrated low incidences of thromboembolic events, bleeding complications, and valve thrombosis.     

Elderly valve replacement with bioprostheses and mechanical prostheses. Comparison by composites of complications

AIM: The goal of aortic valve replacement (AVR) surgery in the elderly (= or >75 years) is to extend survival and minimize valve-related morbidity, mortality and reoperation. As the elderly population lives longer, those with implanted valves are at risk of suffering valve related complications. We hypothesize that bioprostheses are appropriate for the elderly. METHODS: The follow-up evaluation of 966 patients with valves (AVR, 666; mitral valve replacements [MVR], 226; multiple valve replacements [MR], 74) implanted between 1975 and 1999 was examined. There were 879 bioprotheses (BP) and 87 mechanical prostheses (MP). The mean age was 78.9+/-3.3 years (range 75-94.6 years). Concomitant coronary artery bypass was performed in AVR in 51.7%, MVR in 50.4% and MR in 28.4%. Valve type, valve lesion, coronary artery bypass (previous/concomitant), age and gender were considered as independent predictors of composites and survival. The total follow-up was 3905 patient-years. RESULTS: Early mortality was for AVR 9.6% (64), MVR 15.0% (34) and MR 25.7% (19). The late mortality was for AVR 8.8%, MVR 10.4% and MR 8.8%/patient-year. The only independent predictor of survival and valve-related mortality, morbidity and reoperation was age for survival in those with AVR, hazard ratio 1.15 [CL 1.03-1.27] p=0.0094). The BP reoperative rate was 0.5%/patient-year (reoperation was fatal in 6/15) of total, MP reoperative rate was 0% [reasons for reoperation structural valve deterioration (4), non-structural dysfunction (6), prosthetic valve endocarditis (5), reoperation fatality due to non-structural dysfunction (2), prosthetic valve endocarditis (4)]. Overall patient survival at 10 and 15 years, respectively, was 30.5+/-2.4% and 3.6+/-2.2% irrespective of valve position and type. Overall actual and actuarial freedom from valve-related morbidity at 15 years was 96.8+/-0.9% and 93.7+/-2.3%, respectively. Actual and actuarial overall freedom from valve-related mortality at 15 years was 84.3+/-2.4% and 58.4+/-0.9%, respectively. Overall actual and actuarial freedom from valve related reoperation at 15 years was 95.8+/-1.6% and 74.8+/-16.9%, respectively. CONCLUSIONS: BP valves are further confirmed to be a good option for AVR in patients = or >75 years of age.     

Continent urinary diversion. A 5 1/2 year experience.

From August 1982 through March 1988, 531 patients have undergone continent urinary diversion using an ileal reservoir constructed according to the method of Kock. For the past year, the Division of Urology at the USC School of Medicine in Los Angeles has used the principle of Kock reservoir construction for primary lower urinary tract reconstruction after cystectomy in 39 highly selected male patients by means of a ureteroileal urethrostomy. Early complications occurred in 86 of 531 patients (16.2%), resulting in an operative mortality rate of 1.9% (ten of 531). The early complication rate was 16.5% in patients undergoing single stage cystectomy and Kock pouch construction and 15.2% among patients undergoing Kock pouch conversion. Late complications have been analyzed in a group of 489 patients who have undergone Kock cutaneous diversion. The complications unique to continent urinary diversion, their incidence, and the effect of technical modifications in reducing the number of late complications are discussed. Since the time of the last modification, in July 1985, the overall incidence of late complication has dropped to 22%. Based on this ongoing experience, the authors conclude that: 1) the continent ileal reservoir as conceived by Kock remains the best internal reservoir for bladder replacement in terms of volume, accommodation with the lowest internal pressures compared with other alternative reservoir construction, 2) the intussuscepted ileal nipple valve mechanism is a reproducible, highly effective mechanism that prevents reflux in 95% of patients and produces excellent continence, 3) our enthusiasm remains tempered by the need for reoperation in approximately 10-15% of patients, usually due to a pinhole fistula or false passage at the base of the efferent nipple valve mechanism, 4) electrolyte abnormalities rarely occur and gastrointestinal dysfunction is unusual in the absence of radiation, and 5) continent urinary diversion is a viable long-term concept that provides a real alternative in terms of quality of life and self-image for the patient undergoing urinary diversion.     

Hemolysis after mitral valve replacement with mechanical valve prostheses

OBJECTIVE: We evaluated effects of type, size, and orientation of mechanical mitral valve prostheses on hemolysis. METHODS: Subjects were 84 patients who had undergone mitral valve replacement. Lactate dehydrogenase was mainly used as a marker of hemolysis and was measured before surgery, 1 month after surgery, and in the late postoperative period. RESULTS: Valves used included 16 Medtronic-Hall, 32 St. Jude Medical, and 36 CarboMedics valves. Medtronic-Hall valves caused less hemolysis than St. Jude Medical or CarboMedics valves in the late postoperative period. This resulted because hemolysis due to Medtronic-Hall valves was more severe 1 month after surgery than in the late postoperative period and because hemolysis due to St. Jude Medical or CarboMedics valves was more severe in the late postoperative period than 1 month after surgery. One reason for this finding is that cardiac output was greater in the late postoperative period than 1 month after surgery, making regurgitation through the pivots of bileaflet valves more severe. The orifice area and the orientation of prostheses did not affect hemolysis. CONCLUSION: St. Jude Medical or CarboMedics valves caused more severe hemolysis than Medtronic-Hall valves in the late postoperative period.     

Seven year experience with mounted porcine valves.

From March, 1969, through June 1976, 108 porcine aortic xenograft valves were used for mitral or aortic valve replacement in 95 patients. This experience provides one of the longest follow-ups available for evaluation of the porcine bioprosthesis. The first fifteen valves were locally mounted on Cutter stents and preserved in buffered formalin. Subsequent valves were prepared by the Edwards and Hancock Companies with glutaraldehyde preservation. Oral anticoagulation was routinely used for the first 6 weeks following surgery. Hospital mortality was unrelated to the valve type. All but four of the surviving patients with formalin preserved valves have required reoperation because of valve failure. There have been two valve failures in the patients who received gluteraldehyde valves, but there have been no embolic or thrombotic complications. Late cardiac catheterization has shown hemodynamic results equal to or better than prosthetic valves. The continuing long-term results indicate that the porcine xenograft is the valve of choice for cardiac valve replacement.     

Comparison of porcine xenografts and homografts for pulmonary valve replacement in children

BACKGROUND: Due to the limited availability of homografts, different alternatives are used for replacement of the pulmonary valve. This study investigates the value of porcine stentless pulmonary xenografts in pediatric cardiac patients. METHODS: Twenty-three pediatric xenograft (size 10 to 21 mm) recipients were compared with 23 homograft (size 9 to 21 mm) recipients. RESULTS: Hospital mortality was 2 of 23 patients in the xenograft group and 3 of 23 in the homograft group (NS). Six out of 20 xenografts and 1 of 19 homografts were stenotic after 1 year (p = 0.011). Xenograft stenoses were mainly located at the distal anastomosis, while the leaflets were preserved. Homografts showed valvular stenoses and wall calcification. The 1 year freedom from reoperation was 77% in the xenograft and 93% in homograft recipients (NS), and from transcatheter intervention 84% and 100% (p = 0.004), respectively. Transcatheter intervention in 7 xenograft patients and 1 homograft recipient improved stenosis gradients from 65 to 40 mm Hg (mean) in 6 out of 8 patients. Explanted xenografts showed a loss of elastic membranes and proliferating connective tissue scars coated with activated endothelium. CONCLUSIONS: Xenografts demonstrated a higher incidence of supravalvular obstructions, which were possibly due to unfavorable hemodynamics at the distal anastomosis. Histological findings additionally indicated a pronounced immunological response. Interventional angioplasty lowered the rate of reoperation. Thus, the use of xenografts in children can be accepted as a second choice when a homograft is unavailable.     

The Medtronic-Hall cardiac valve: 7 1/2 years' clinical experience

Clinical information on the Medtronic-Hall valve prosthesis was obtained by reviewing the records of 379 patients, 164 of whom had aortic valve replacement (AVR), 163 of whom had mitral valve replacement (MVR), and 52 of whom had double valve replacement over 90 months (1,225 patient-years) (mean follow-up, 42.01 +/- 1.3 months [+/- standard error]). Mean age was 53.8 +/- 12 years. One hundred ninety-three patients (50.9%) had some type of concomitant operation, such as tricuspid annuloplasty, coronary artery bypass grafting, or resection of ascending aortic aneurysm. Ninety-one percent were in New York Heart Association (NYHA) Functional Class III or IV preoperatively. Early mortality and late mortality were 7.7% (29 patients) and 13.5% (51 patients), respectively. The actuarial survival at 7 1/2 years was 74.1 +/- 2.7% for the total group and 69.0 +/- 4.5% for those having AVR, 81.0 +/- 3.2% for those having MVR, and 67.0 +/- 8.9% for those having double valve replacement. All patients but 2 were maintained on a regimen of chronic anticoagulation with warfarin sodium. Twenty-six thromboembolic episodes occurred (2.1/100 patient-years): 13 after MVR (2.3/100 patient-years), 11 after AVR (2.1/100 patient-years), and 2 after double valve replacement (1.4/100 patient-years). Four thromboembolic episodes were fatal; no valve thrombosis occurred. There were no structural failures. Of the 350 late survivors, 92% were in NYHA Functional Classes I and II. Total valve-related complications have been minimal.(ABSTRACT TRUNCATED AT 250 WORDS)     

Results of valve replacement with Omniscience mechanical prostheses

BACKGROUND: The Omniscience mechanical valve has been the subject of multiple clinical investigations with variable results, including reports of high complication and reoperation rates. METHODS: Records of all patients who received Omniscience valves were reviewed, and follow-up interviews were conducted to determine the incidence of valve-related morbidity, mortality, and functional results. Incidence of complications was expressed as events per 100 patient-years follow-up. Survival and freedom from valve-related complications and mortality were calculated using a product limit method. RESULTS: Between 1984 and 1988, 192 patients received 213 Omniscience valves [93 mitral (M), 79 aortic (A), and 20 multiple (D) valve replacements]. Perioperative mortality was 9%. The incidence of major valve-related morbidity was as follows: thrombosis, 1.30 M, 0.17 A, 0.72 D; endocarditis, 0.48 M, 0.18 A, 0 D; hemorrhagic, 4.67 M, 2.84 A, 5.00 D; embolic, 2.90 M, 2.27 A, 1.57 D; nonstructural dysfunction, 1.66 M, 1.08 A, 2.27 D; reoperation, 4.02 M, 1.99 A, 6.48 D. All explanted valves (n = 43) were examined, and 40% (n = 17) were found to have limited disc excursion in the absence of thrombus. Freedom from valve-related morbidity, mortality, or reoperation at 10 years was 22% for mitral, 39% for aortic, and 17% for multivalve replacements. At follow-up, only 73% of patients were New York Heart Association class I or II. Five- and 10-year estimated survivals were 72% and 55% for M, 80% and 51% for A, and 65% and 50% for D replacements. CONCLUSIONS: Use of the Omniscience valve provided poor functional improvement and a significant incidence of valve-related complications, including the need for reoperation.     

A 5 1/2 year experience with the St. Jude Medical cardiac valve prosthesis. Early and late results of 737 valve replacements in 671 patients

Between June 12, 1978, and June 12, 1983, 737 St. Jude Medical valves were implanted in 671 patients (431 males, 240 females) ranging in age from 9 months to 82 years (mean 55 years); 16 of these patients (2.3%) were less than or equal to 15 years and 82 (12.2%) were greater than or equal to 70 years. Associated procedures were performed in 28.2% of the 500 aortic valve replacements, 13.3% of the 105 mitral valve replacements, and 10.6% of the 66 double mitral and aortic valve replacements. Hospital mortality (less than or equal to 30 days) was 3.6% (18/500 patients) for aortic, 4.7% (5/105 patients) for mitral, and 0% for double valve replacement. Only one of these 23 hospital deaths was possibly valve-related. Complete follow-up was achieved during December, 1983, and January, 1984, to provide a minimum follow-up of 6 months. Follow-up has been 100% for a total of 1,619 patient-years, with a mean follow-up of 2 1/2 years. There were 41 late deaths (6.1%): 30 in the aortic group, eight in the mitral group, and three in the double valve replacement group. Fourteen (34.2%) of these late deaths have been considered valve-related. At 5 1/2 years, the actuarial survival rate, hospital mortality excluded, is 91% for aortic, 90% for mitral, and 95% for double valve replacement. Functional improvement of these patients is quite satisfactory: Preoperatively, 60.3% were in Class III or IV of the New York Heart Association, whereas postoperatively, 99.5% of the patients are in Class I or II. As 78 patients (65 aortic, 10 mitral, and three double valve replacement) did not receive anticoagulation therapy for a total period of 84 patient-years, the incidence of valve thrombosis, systemic embolism, and sudden or suspicious deaths in this group was compared with that in a group of 630 patients (including 60 patients from the first group who were given anticoagulants afterwards) subjected to long-term anticoagulation for a total period of 1,535 patient-years. A significantly higher incidence of valve thrombosis and systemic embolism was observed in the absence of anticoagulation. Anticoagulant-related complications occurred in 10 patients, with an incidence of 0.65/100 patient-years. On the basis of this 5 1/2 years of experience, the St. Jude Medical valve appears to be an excellent mechanical prosthesis for cardiac valve replacement, in terms of hemodynamic performance and low thrombogenicity, in patients receiving anticoagulants.     

Clinical experience with porcine xenografts in the mitral position

In a 7-year period, 120 porcine xenografts, 16 of Hancock and 104 of Carpentier-Edwards type, were implanted in the mitral position in patients with isolated mitral valve disease. The operative mortality was 4.2%. The actuarial survival after 5 years was 93%. Death during the observation period was valve-related in two cases. Three valves had to be exchanged, one because of calcification and two because of prosthetic endocarditis. The risk of contracting prosthetic endocarditis was 0.38% per patient year. All the patients received peroral anticoagulant medication indefinitely. Two minor embolic episodes occurred, both in the first 6 post-operative months. The probability of freedom from thromboembolism was thus 98.2% after 7 years. In functional evaluation of 92 patients observed for at least 6 months, more than 90% were in NYHA class I or II. Porcine xenograft is a good valve substitute in the mitral position with a low incidence of complications, especially of thromboembolism, in patients on maintenance anticoagulant therapy. Long-term observations of this type of valve substitute are not yet available, however.     

Sarpogrelate reduces mechanical hemolysis in patients with heart valve prostheses.

OBJECTIVE: We evaluate the clinical efficacy of sarpogrelate, an antiplatelet drug that improves red blood cell deformability, to reduce the intravascular hemolysis problems suffered frequently by patients implanted with heart valve prostheses. SUBJECTS: Subjects were 34 patients undergoing mechanical heart valve replacement and having serum lactate dehydrogenase concentrations 20% above the maximum normal range. METHOD: Sarpogrelate was given daily, 100 mg orally for the first 6 months and 200 mg thereafter. RESULTS: Average serum lactate dehydrogenase decreased significantly from 423 +/- 108 IU/l, to 391 +/- 83 IU/l with the 100 mg dose, and to 361 +/- 86 IU/l with the 200 mg dose. The percentage of reticulocytes decreased from 15.5 +/- 5.3/1000 to 15.3 +/- 5.7/1000 at the 100 mg dose and 13.1 +/- 4.0/1000 at the 200 mg dose. Serum iron concentrations increased significantly from 63.2 +/- 24.8 micrograms/dl to 76.2 +/- 16.2 micrograms/dl at the 100 mg dose, and to 70.9 +/- 26.2 micrograms/dl with the 200 mg dose. CONCLUSION: Sarpogrelate is a useful drug for patients with implanted heart valve prostheses and subsequent high serum lactate dehydrogenase because it works as an antiplatelet drug and reduces mechanical hemolysis.     

Aortoenteric fistula. A 7 year urban experience

In this 7 year review of the operative records of a single city's teaching hospitals, we found 28 patients with aortoenteric fistulas. Among 25 patients with secondary aortoenteric fistulas, 80 percent presented with a herald bleed. Sepsis was rare. Most diagnostic maneuvers, with the possible exception of upper gastrointestinal tract endoscopy, computerized axial tomography, or ultrasonography, were unhelpful. As noted by others, graft excision, aortic ligature, and extraanatomic bypass is the only predictably useful operative therapy. Initial hospital survival was 60 percent, but this decreased to 36 percent because recurrent aortic complications developed in more than half the initial survivors, 75 percent of whom died. Although the pathogenesis of aortoenteric fistulas remains obscure, our study demonstrates that patients who have previously undergone complicated, repeated, or emergency aortic operations, including previous repair of an aortoenteric fistula, are at high risk for the development of another aortoenteric fistula. Serial screening by noninvasive imaging techniques, such as ultrasonography or computerized axial tomography, may be warranted in these patients.     

用无支架生物瓣膜行主动脉瓣置换术的早期临床经验

目的探讨无支架生物瓣的置入技术及其早期临床效果.方法对12例平均年龄65岁的主动脉瓣病变病人,选用St.Jude公司提供的TorontoSPV瓣膜,行主动脉瓣置换术.结果全组手术死亡1例,平均主动脉阻断时间(95.0±12.3)?min,其中单纯主动脉瓣置换者为(74.0±9.2)?min.术后1个月随访超声心动图显示均无主动脉瓣反流,跨瓣压差明显较其他人工瓣膜小,左心室舒张末期内径明显缩小,无栓塞、出血等并发症.结论尽管无支架生物瓣膜置入有一定难度,但其优良的血液动力学性能,提示其能提高病人的远期疗效.     

Prediction of long-term complications associated with aortic valve prostheses. A 10-17 year follow-up

Long-term complications following implantation of aortic valve prosthesis were assessed in 139 patients who had survived greater than 30 postoperative days (maximum follow-up 17 years). Most of the prostheses were Starr-Edwards valves (38 silastic ball, SESB, and 96 cloth-covered, SECC). All patients received maintenance coumarin. The rate of thromboembolic complications was 1.6/100 patient-years, without difference between SESB and SECC valves although there were no episodes with SESB from 6 years postoperatively. The overall rate of valve-related complications (VRC)--thromboembolism, hemorrhage, endocarditis, re-replacement, etc.--was 4.2/100 patient-years. High preoperative cardiothoracic index (CTI) significantly increased the incidence of VRC. Preoperative NYHA class III-IV and high CTI similarly influenced the rate of serious VRC (= VRC excluding extremity emboli, epistaxis and subcutaneous bleeding). The valve-and-heart-related morbidity (= VRC including myocardial infarction and pacemaker requirement) was also influenced by preoperative CTI. The long-term complications thus were not exclusively attributable to the prosthesis, but also to preoperative patient-related data.     

Clinical comparison of St. Jude and porcine mitral valve prostheses

One hundred and six consecutive patients who had mitral valve replacement with either a St. Jude or porcine heterograft prosthesis were prospectively studied. The 2 groups are similar with respect to 67 clinical and operative factors and allow comparison of valve performance as an independent variable. Total follow-up is 3,312 patient-months (mean 36 months, range 2-57 months, 94% complete). There are no statistical differences in symptomatic improvement or mortality by life table analysis. Valve-related complications expressed as percent per patient-year are: reoperation: 1.8 St. Jude and 3.8 porcine; endocarditis: 1.2 and 1.9; regurgitant murmur: 2.3 and 1.9; hemolysis: 1.8 and 0.0; late thromboembolism: 1.8 and 1.0; hemorrhage: 2.9 and 2.9; and valve failure: 0.0 and 1.0. There were no significant differences found. Actuarial survival at 3 years was 78% in St. Jude and 81% in porcine patients. Forty-six percent of patients with St. Jude valves and 55% of patients with porcine valves were alive and free of all complications at latest follow-up. The clinical performance of St. Jude and porcine mitral valves are similar over this period of intermediate follow-up.     

Long-term experience with the Sorin Bicarbon and Edwards Mira mechanical valve prostheses in the mitral position

OBJECTIVE: Sorin Bicarbon (SB) and Edwards Mira (EM) valves have an identical mechanical design but different sewing cuffs. The purpose of this retrospective study was to analyze the long-term clinical and echocardiographic outcomes after mitral valve replacement with these two valves in a combined population of patients. METHODS: We retrospectively reviewed records of 73 patients who underwent mitral valve replacement using SB (n = 19) or EM (n = 54) valves. Preoperatively, 49 patients (68.1%) were in New York Heart Association (NYHA) functional class III or IV. Concomitant procedures were performed in 52 patients (71.2%). Early and late postoperative echocardiography was performed in 69 and 57 patients, respectively. RESULTS: Operative mortality was 4.1%, and early morbidity was 9.6%. Overall patient survival at 9 years was 85.1% +/- 4.8%. Actuarial freedom from valve-related death was 95.4% +/- 2.6% at 9 years. As shown by Doppler echocardiography, the early and late mean transprosthetic pressure gradients were 3.4 +/- 1.4 mmHg and 3.8 +/- 2.1 mmHg, respectively. At the end of follow-up, 98.4% of survivors were in NYHA class I or II. CONCLUSION: The Sorin Bicarbon and, Edwards Mira mechanical valves in the mitral position provide satisfactory long-term clinical and echocardiographic performance.