Immediate and long-term results of valve replacement for native and prosthetic valve endocarditis

BACKGROUND: The objective of the present study was to compare current results of prosthetic valve replacement following acute infective native valve endocarditis (NVE) with that of prosthetic valve endocarditis (PVE). Prosthetic valve replacement is often necessary for acute infective endocarditis. Although valve repair and homografts have been associated with excellent outcome, homograft availability and the importance of valvular destruction often dictate prosthetic valve replacement in patients with acute bacterial endocarditis. METHODS: A retrospective analysis of the experience with prosthetic valve replacement following acute NVE and PVE between 1988 and 1998 was performed at the Montreal Heart Institute. RESULTS: Seventy-seven patients (57 men and 20 women, mean age 48 +/- 16 years) with acute infective endocarditis underwent valve replacement. Fifty patients had NVE and 27 had PVE. Four patients (8%) with NVE died within 30 days of operation and there were no hospital deaths in patients with PVE. Survival at 1, 5, and 7 years averaged 80% +/- 6%, 76% +/- 6%, and 76% +/- 6% for NVE and 70% +/- 9%, 59% +/- 10%, and 55% +/- 10% for PVE, respectively (p = 0.15). Reoperation-free survival at 1, 5, and 7 years averaged 80% +/- 6%, 76% +/- 6%, and 76% +/- 6% for NVE and 45% +/- 10%, 40% +/- 10%, and 36% +/- 9% for PVE (p = 0.003). Five-year survival for NVE averaged 75% +/- 9% following aortic valve replacement and 79% +/- 9% following mitral valve replacement. Five-year survival for PVE averaged 66% +/- 12% following aortic valve replacement and 43% +/- 19% following mitral valve replacement (p = 0.75). Nine patients underwent reoperation during follow-up: indications were prosthesis infection in 4 patients (3 mitral, 1 aortic), dehiscence of mitral prosthesis in 3, and dehiscence of aortic prosthesis in 2. CONCLUSIONS: Prosthetic valve replacement for NVE resulted in good long-term patient survival with a minimal risk of reoperation compared with patients who underwent valve replacement for PVE. In patients with PVE, those who needed reoperation had recurrent endocarditis or noninfectious periprosthetic dehiscence.     

Reoperative surgery for degenerated aortic bioprostheses: predictors for emergency surgery and reoperative mortality.

OBJECTIVE: The long-term outcome of patients with aortic bioprosthetic valves could be improved by decreasing the reoperative mortality rate. METHODS: Predictors of emergency reoperation and reoperative mortality were identified retrospectively in 172 patients who had the first bioprosthetic aortic valve replacement between 1975 and 1988 (mean age 46+/-13 years) and were subjected to replacement of the degenerated bioprostheses between 1978 and 1997 (mean age 56+/-14 years). Emergency reoperation had to be performed in 31 patients (18%). RESULTS: The operative mortality was 5.2% (9/172), 22.6% for emergency (odds ratio 11.17; 95%-confidence limit 4.33-28.85) and 1.4% for elective replacement of the degenerated aortic bioprosthesis (P<0.0001; OR=20.3). Patients who died at reoperation had higher transvalvular gradients before the primary aortic valve replacement (P=0.007), received smaller bioprostheses at the first operation (P=0.03), had later recurrence of symptoms after the first aortic valve replacement (P=0.04), a higher pre-reoperative New York Heart Association (NYHA) class (P=0.02), and a higher incidence of coronary artery disease (P=0.001) and pulmonary artery hypertension (P=0.009). Endocarditis before the primary aortic valve replacement (P=0.004), postoperative pneumonia at the first operation (P=0.005), pulmonary hypertension (P=0.0004) acquired during the interval, later recurrence of symptoms (P=0.04) after the first operation, a lower ejection fraction at the time of reoperation (P=0.03) and acute onset of bioprosthetic regurgitation (P=0.00002) were predictors for emergency surgery. Higher transvalvular gradients at the primary aortic valve replacement (P=0. 006), coronary artery disease (P=0.003) acquired during the interval, the need for concomitant coronary artery revascularization (P=0. 001), sex (P=0.02) and size (P=0.05) and type of the bioprostheses used (P=0.007) were incremental predictors for reoperative mortality which were independent of emergency surgery. CONCLUSIONS: Elective replacement of failed aortic bioprostheses is safe. Patients undergoing emergency reoperation have a considerably higher mortality. They can be identified by a history of native aortic valve endocarditis, higher transvalvular gradients at primary aortic valve replacement, smaller bioprostheses, and pulmonary hypertension or coronary artery disease acquired during the interval. A failing bioprosthesis must be replaced at its first sign of dysfunction.     

Late incidence and determinants of reoperation in patients with prosthetic heart valves.

OBJECTIVES: Reoperation is a relatively common event in patients with prosthetic heart valves, but its actual occurrence can vary widely from one patient to another. With a focus on bioprosthetic valves, this study examines risk factors for reoperation in a large patient cohort. METHODS: Patients (N=3233) who underwent a total of 3633 operations for aortic (AVR) or mitral valve replacement (MVR) between 1970 and 2002 were prospectively followed (total 21,179 patient-years; mean 6.6+/-5.0 years; maximum 32.4 years). The incidence of prosthetic valve reoperation and the impact of patient- and valve-related variables were determined with actual and actuarial methods. RESULTS: Fifteen-year actual freedom from all-cause reoperation was 94.1% for aortic mechanical valves, 61.4% for aortic bioprosthetic valves, 94.8% for mitral mechanical valves, and 63.3% for mitral bioprosthetic valves. In both aortic and mitral positions, current bioprosthesis models had significantly better durability than discontinued bioprostheses (15-year reoperation odds-ratio 0.11+/-0.04; P<0.01 for aortic, and 0.42+/-0.14; P=0.009 for mitral). Current bioprostheses were significantly more durable in the aortic position than in the mitral position (14.3+/-6.8% more freedom from 15-year reoperation; (P=0.018)). Older age was protective, but smoking was an independent risk factor for reoperation after bioprosthetic AVR and MVR (hazard ratio for smoking 2.58 and 1.78, respectively). In patients with aortic bioprostheses, persistent left ventricular hypertrophy at follow-up and smaller prosthesis size predicted an increased incidence of reoperation, while this was not observed in patients with mitral bioprostheses. CONCLUSIONS: These analyses indicate that current bioprostheses have significantly better durability than discontinued bioprostheses, reveal a detrimental impact for smoking after AVR and MVR, and indicate an increased reoperation risk in patients with a small aortic bioprosthesis or with persistent left ventricular hypertrophy after AVR.     

Porcine versus pericardial bioprostheses: a comparison of late results in 1,593 patients

From 1976 to 1988, 1,593 patients underwent valve replacement with a porcine (878 patients) or a pericardial bioprosthesis (715 patients). There were 701 aortic, 678 mitral, and 214 multiple-valve replacements. Follow-up was obtained for 1,559 patients (98%). Early mortality was 9% (79 patients) in the porcine valve group and 5% (37 patients) among patients with a pericardial valve (p less than 0.01). Late survival after replacement with porcine valves was 80% +/- 1% and 62% +/- 3% at 5 and 10 years, respectively. With pericardial valves, 5-year survival was 79% +/- 2%. Among valve-related complications, rates of freedom from thromboembolism, endocarditis, and hemorrhage after 6 years were similar for both valve groups. Freedom from reoperation at 6 years was also similar after aortic (96% versus 91%) or multiple-valve replacement (95% versus 88%). However, for mitral valve replacement, freedom from reoperation was significantly better with porcine valves than with pericardial valves at 6 years (92% versus 68%; p less than 0.001). This difference was mainly due to the Ionescu-Shiley valve, which accounted for 83% of primary tissue failures among pericardial bioprostheses implanted in the mitral position (10/12 patients). After 6 years, freedom from primary tissue failure of mitral valves was 92% +/- 2% with porcine and 70% +/- 11% with pericardial bioprostheses (p less than 0.0001). The degree of clinical improvement among survivors was similar with both valve types. Thus, in the aortic position, pericardial valves compare with porcine valves up to 6 years, whereas in the mitral position, the durability of the former is significantly less, mainly because of the suboptimal performance of the Ionescu-Shiley pericardial bioprosthesis.     

Aortic root replacement with cryopreserved allograft for prosthetic valve endocarditis

BACKGROUND Our strategy has been to treat aortic prosthetic valve endocarditis (PVE) with radical debridement of infected tissue and aortic root replacement with a cryopreserved aortic allograft. This study examines the effectiveness of this strategy on hospital mortality and morbidity, recurrent endocarditis, and survival. METHODS: From 1988 through 2000, 103 patients with aortic PVE underwent root replacement with a cryopreserved aortic allograft. Abscesses were present in 78%, and aortoventricular discontinuity was present in 40%. Thirty-two patients had at least one previous operation for endocarditis. In 23 patients with a history of native valve endocarditis, the allograft was implanted after one episode (17 patients), two episodes (5 patients), or three episodes of PVE (1 patient). In the 80 patients without a history of native valve endocarditis, the allograft was placed after one previous aortic valve replacement (57 patients), two (19), or three (4) previous aortic valve replacements. Among the 92 patients with positive cultures, 52 had staphylococcal organisms, 20 had streptococcal, 6 had fungal, 4 had gram-negative, and 6 had enterococcal organisms. Mean follow-up was 4.3 +/- 2.9 years. RESULTS: Hospital mortality was 3.9%. Permanent pacemakers were required in 31 patients. Survival at 1 year, 2 years, 5 years, and 10 years was 90%, 86%, 73%, and 56%, respectively, with a risk of 5.3% per year after 6 months. Four patients underwent reoperation for recurrent PVE of the allograft (95% freedom from recurrent PVE at > or = 2 years). Risk of recurrent PVE peaked at 9 months and then declined to a low level by 18 months. CONCLUSIONS: A strategy of radical debridement and aortic root replacement with a cryopreserved aortic allograft for aortic PVE is safe, effective, and recommended.     

Mechanical valve replacement in children and teenagers

A previous study from this unit showed that only 19% of children with mitral bioprostheses were free from complications after 7 years and prompted us to review the performance of new-generation mechanical prostheses implanted in the same population group. In a 5-year period (1980-1985), 352 patients 20 years old and younger (mean age 15.3 +/- 4 years) with rheumatic valvular disease had 177 mitral, 62 aortic and 113 double (mitral + aortic) valve replacements with Medtronic-Hall or St. Jude prostheses. The overall early mortality was 6.3%. All survivors, followed up for a total of 1171 patient-years, received oral anticoagulation. The late mortality for mitral, aortic and double valve replacement was 4.1% per patient-year, 4.3% per patient-year and 8.0% per patient-year, respectively (P less than 0.05), and was valve-related in 46% of the cases. Twenty-nine patients, all but 2 in the mitral and double valve replacement groups, were reoperated upon (2.5% per patient-year), mainly for infective endocarditis (34%), for prosthetic thrombosis (33%) and for bland periprosthetic leak (31%). The incidence of thrombotic obstruction was 1.1% per patient-year: mitral valve replacement, 1.0% per patient-year; aortic valve replacement 0.5% per patient-year; and double valve replacement, 1.7% per patient-year; P less than 0.05) and was fatal in 33% of the cases. Major systemic thromboembolism occurred at the rate of 1.4% per patient-year, similar in the three groups. The incidence of prosthetic endocarditis was 0.9% per patient-year.(ABSTRACT TRUNCATED AT 250 WORDS)     

Actuarial analysis of the risk of prosthetic valve endocarditis in 1,598 patients with mechanical and bioprosthetic valves

We reviewed the charts of 1,598 patients undergoing valve replacement at the National Institutes of Health, Bethesda, Md, from 1956 through 1981. Retrospective analysis disclosed that 43 patients had prosthetic valve endocarditis (PVE). Twelve patients had early (less than 60 days after operation) and 31 patients had late (greater than 60 days after operation) endocarditis. The cumulative risk was 3% at five years and 5% at ten years. We also calculated the interval risk of PVE. The high risk of early PVE development peaked 15 days after operation. The peak risk was 45 episodes per 100,000 patient days. The risk then declined rapidly and from 150 days to 20 years remained stable at approximately one episode per 100,000 patient days. Nine hundred fifty-two patients had valve replacement with a Starr-Edwards prosthesis and 363 patients had valve replacement with a bioprosthetic valve; there was no significant difference in the risk of PVE in either group. Neither the valve make, position, model, nor the number of valves implanted affected the frequency of PVE or the mortality. Actuarial techniques disclosed the high early risk of PVE, the prolonged risk of PVE up to 150 days after operation, and the low but persistent risk late after operation. There was no significant difference in the risk of PVE in patients with bioprosthetic v mechanical valves.     

Results of reoperation for primary tissue failure of porcine bioprostheses

Results of reoperation for primary tissue failure of porcine bioprostheses were evaluated in 574 patients discharged from the hospital from 1970 to 1981. A total of 413 had undergone isolated mitral valve replacement and 161 isolated aortic valve replacement. Through March, 1984, 88 patients (15%) had required reoperation: 59 had undergone mitral and 29, aortic valve replacement. Primary tissue failure was the main cause of bioprosthetic dysfunction; it occurred in 64 patients (46 mitral and 18 aortic) at a mean postoperative interval of 93 +/- 4 months (range 34 to 158). During the same period, 11 patients required reoperation for bioprosthetic endocarditis, 11 for paravalvular leak, and two for thrombosis. These patients are not included in this review. Reoperation for primary tissue failure was performed after a mean interval of 72 +/- 6 months (range 38 to 158) for patients with aortic bioprostheses and after 101 +/- 5 months (range 34 to 153) for those with mitral bioprostheses (p less than 0.05). Overall mortality at reoperation was 12.5%: 11% for the mitral group and 16% for the aortic group. In 62 patients (45 mitral and 17 aortic) primary tissue failure was caused by calcification of the cusps, associated with severe fibrous tissue overgrowth in seven. Bioprosthetic failure was caused by an intracuspal hematoma in one patient with mitral valve replacement and by lipid infiltration of the cusps in one patient with aortic valve replacement. Actuarial freedom from bioprosthetic primary tissue failure at 12 years is 61% +/- 5% for the mitral group and 69% +/- 7% for the aortic group. On the basis of our long-term follow-up of patients after mitral or aortic replacement with a porcine bioprosthesis, we conclude: primary tissue failure is the most frequent indication for reoperation in patients with a porcine bioprosthesis; calcification of the cusp tissue is the leading cause of primary tissue failure; reoperation for primary tissue failure may be a major concern, although mortality for elective cases is low; and the limited durability of porcine bioprostheses suggests their use be restricted to selected patients.     

Reoperative cryopreserved root and ascending aorta replacement for acute aortic prosthetic valve endocarditis

BACKGROUND: Prosthetic aortic valve endocarditis (PVE) is an important complication of aortic valve replacement (AVR) and is a particularly difficult situation after an operation combining AVR with ascending aortic replacement. METHODS: From 1988 through 2000, 27 patients with aortic valve PVE after previous ascending aortic replacement (aortic root replacement in 13, aortic valve replacement with a supracoronary graft in 14) underwent reoperation for aortic root replacement with a cryopreserved aortic allograft and prolonged intravenous antibiotic therapy. All patients were considered to have active PVE (25 with positive cultures); root abscess formation was present in 89% and aortoventricular discontinuity in 41%. RESULTS: One patient (3.7%) died in-hospital, and permanent pacemakers were required in 10 patients (37%). Mean postoperative follow-up interval was 3.9 +/- 3.0 years, and survival at 1, 2, 5, and 7.5 years was 92%, 88%, 70%, and 56%, respectively. One patient underwent reoperation for recurrent PVE 8 months after operation. CONCLUSIONS: Radical debridement of infected prosthetic material and tissue, and allograft aortic root and ascending aorta replacement, combined with intravenous antibiotic therapy, appears to achieve a low hospital mortality and a high degree of freedom from recurrent infection for patients with PVE after AVR and ascending aortic replacement.     

Operative risk of reoperative aortic valve replacement

OBJECTIVE: The contemporary risk of reoperative aortic valve replacement is ill-defined. We therefore compared the recent early results of reoperative and primary aortic valve replacement in our institution. METHODS: Between January 1993 and January 2001, a total of 162 patients underwent reoperative aortic valve replacement with or without coronary artery bypass grafting, and 2290 underwent primary aortic valve replacement with or without coronary artery bypass grafting. The reoperative and primary groups were similar with regard to gender (37% female in both), preoperative New York Heart Association functional class (2.8 +/- 1 vs 2.8 +/- 1), and ejection fraction (58% +/- 15% vs 57% +/- 15%). Patients undergoing reoperative aortic valve replacement were younger than those undergoing primary aortic valve replacement (64 +/- 15 years vs 70 +/- 13 years, P < .001). Previous prostheses were xenografts in 77 patients (48%), homografts and autografts in 25 (15%), and mechanical prostheses in 60 (37%). Mean time to reoperation was 9.7 +/- 6.8 years. RESULTS: Early mortality for reoperative aortic valve replacement (8/162, 5%) was not statistically different from that for primary aortic valve replacement (71/2290, 3%, P = .20). Endocarditis was more common in the reoperative group (22% vs 3%, P < .001); when endocarditis was excluded from the analysis, early mortality was 3% in both groups. Multivariate predictors for early mortality were prosthetic valve endocarditis ( P < .001, odds ratio 9.8), advanced preoperative functional class ( P < .001, odds ratio 2.0), peripheral vascular disease ( P = .008, odds ratio 2.0), preserved left ventricular ejection fraction ( P = .004, odds ratio 0.98), and male gender ( P = .009, odds ratio 0.49). After adjustment for these factors, there was no difference in early mortality between the groups ( P = .095). CONCLUSION: The risk of reoperative aortic valve replacement is similar to that for primary aortic valve replacement. These data support the expanded use of bioprosthetic valves in younger patients.     

Long-term results of porcine bioprosthetic heterograft; a 13-years' experience

One hundred and ninety-four patients underwent valve replacements with the glutaraldehyde-preserved porcine bioprostheses (133 Hancock valves, 39 Angell-Shiley valves, 22 Carpentier-Edwards valves and 3 other valves) from 1974 through 1979. There were 105 women and 89 men, whose age ranged 18 to 62 (mean 38.8) years. One hundred and eighty-two patients had mitral bioprosthetic valve replacement (BVR)s, of which 52 had combined aortic mechanical valve replacements, 8 had aortic BVR's, 3 had tricuspid BVR's and 3 had multi-BVR's. Operative mortality was 10.8%. Only one patient was lost to follow-up. Cumulative duration of follow-up is 1421 patient-years. Linearized rate of anticoagulant related hemorrhage, thromboembolism (TE), prosthetic valve endocarditis (PVE), primary tissue failure (PTF) and valve dysfunction (VD) were 0.07, 1.62, 0.49, 2.74 and 3.66% per patient-year. Actuarial freedom from TE, PVE, PTF and VD were 87.0 +/- 2.7%, 95.6 +/- 1.5%, 65.2 +/- 4.9% and 56.9 +/- 5.6% at 13 years. Actuarial survival rate was 67.4 +/- 4.0% at 13 years. Long term follow-up after valve replacement with porcine bioprosthetic valve confirms low thrombogenicity. But primary tissue failure was the chief cause of valve dysfunction and represent a major problem. At this time, we are going to use porcine bioprosthetic valve in the selected patients, that is in the situations in which anticoagulation is contraindicated.     

More than ten years' follow-up of the Hancock porcine bioprosthesis in Japan.

From February 1975 through October 1981, 256 Hancock porcine bioprostheses (Johnson & Johnson Cardiovascular, King of Prussia, Pa.) (60 aortic, 169 mitral, and 27 pulmonary/tricuspid position) were implanted in 220 patients (104 male and 116 female, aged 9 to 67 years; mean 43.3) at Kyushu University Hospital in Japan. The procedures include 41 aortic valve replacements, 121 mitral valve replacements, 4 pulmonary valve replacements, 6 tricuspid valve replacements, and 48 combined valve replacements (31 aortic plus mitral, 13 mitral plus tricuspid, and 4 aortic plus mitral plus tricuspid). Hospital mortality was 6.4%. Follow-up was 98% during 8 to 14 (mean 10.5) years. Cumulative follow-up was 1836 patient-years and 2078 valve-years. At 10 years the overall actuarial survival rate, including hospital morality, was 70% +/- 3%, and freedom from valve-related mortality with sudden death was 87% +/- 3%. More than half of the current survivors required no anticoagulant therapy. Freedom from thromboembolism or anticoagulant-related hemorrhage (or both) and prosthetic valve endocarditis was common. Freedom from structural valve failure and reoperation declined more than 9 years after replacement of left-sided heart valves but not after replacement of right-sided heart valves. Sixty-seven patients underwent 68 repeat operations, and there were four deaths (5.9%). The rate of freedom from overall valve-related complications at 10 years was 62% +/- 8% for aortic valve replacement, 53% +/- 5% for mitral valve replacement, 80% +/- 13% for pulmonary/tricuspid valve replacement, and 42% +/- 9% for combined valve replacement. There was a significant difference between pulmonary/tricuspid valve replacement and combined valve replacement (p less than 0.05). The Hancock bioprosthesis is suitable for the replacement of valves in the right side of the heart but not for combined valve replacement.     

Mid-term follow-up in patients with Biocor porcine bioprostheses

BACKGROUND: Prosthetic cardiac valves have increased life expectancy of patients (pts) with valvular heart disease. Bioprosthetic complications required devices replacements within 10 years of implantation; structural valve deterioration (SVD) has emerged as the major cause of reoperation. We reviewed survival and prosthetic complications of Biocor porcine bioprostheses implanted in mitral, aortic and mitro-aortic position. METHODS: Between January 1991 and January 2001 446 pts (192 males; 254 females; mean age 73.4+/-6.7 year, range 40-91) received 258 aortic, 138 mitral and 50 mitro-aortic Biocor porcine valves; of these 83 pts have previous different types of prosthetic devices (15 aortic, 53 mitral and 15 double). Concomitant cardiac procedures, namely myocardial revascularization, were performed in 91/446 pts (20.5%). All explanted bioprostheses (BPS) were available for pathologic investigation. Follow-up included 1319 pt.-years and was 98% complete with a median time of 36 pt.-months. RESULTS: Perioperative mortality was 6.8% (30/446 pts; 12 aortic, 17 mitral and 1 double) and was mostly related to reoperations. At the end of follow-up 18.5% of pts died (77/416), 12 deaths were valve-related with freedom from valve related mortality of 94% at 9 years. Survival was 54% at 9 years. It was 63%, 41% and 62% for aortic, mitral and double valve replacement, respectively. At follow-up 87% of pts. were in NYHA I-II class and 13% were in III-IV class; 55% were in sinus rhythm, 36% in atrial fibrillation and 9% had a pace-maker. Eighty-five percent of pts were anticoagulated. There were 6 thromboembolic and 5 anticoagulant-related haemorrhagic episodes with no significant difference between aortic and mitral position (p=0.7). The event freedom was respectively 92% and 98.5% at 9 years. Prosthetic valve endocarditis (PVE) and non-SVD freedom were 96% and 93% at 9 years. SVD due to tissue degeneration, calcification and cusp's tears affected 2 pts with 94% freedom at 9 years. Overall freedom from all valve-related complications was 80% at 9 years and freedom from reoperation was 92% at 9 years. CONCLUSIONS: (1) Our intermediate-term follow-up of the Biocor porcine valve (BPS) showed excellent durability in all positions. (2) The aortic patients and especially the oldest group had better results than the mitral patients (41% vs. 63% 9 years survival, p=0.0004). (3) Higher mitral risk was related to higher prevalence of reoperations. (4) The incidence of anticoagulation-related complications is low in both aortic and mitral position without significant difference (p=0.7). 4) A longer follow-up is required to get more information about SVD timing.     

Use of the Carpentier-Edwards porcine bioprosthesis: assessment of a patient selection policy.

The Carpentier-Edwards bioprosthesis was implanted in 369 patients (414 valves) between May 1977 and December 1987 (age 67.2 +/- 0.5 years); 242 had aortic valve replacement, 80 had mitral valve replacement, 44 had multiple valve replacement, of which 41 were aortic and mitral valve replacement, 2 had isolated tricuspid valve replacement, and 1 had a pulmonary valve replacement. The selection criteria were the following: shorter life expectancy (253 patients) or contraindications to anticoagulants for organic (113 patients) or psychologic (38 patients) reasons, or both. The early mortality rate was 11.1% (aortic valve replacement, 9.1%; mitral valve replacement, 12.4%; aortic and mitral valve replacement, 23.1%). Total cumulative follow-up was 1456 pt-yr (mean 4.4 years, range 1 to 148 months), and the patient evaluation was 99.5% complete. Late mortality was 4.9%/pt-yr. Five-year survival was 70.4% +/- 2.7% overall, 74.3% +/- 3.2% after aortic valve replacement, 60.9% +/- 6.2% after mitral valve replacement (p < 0.03), and 60.7% +/- 8.1% after aortic and mitral valve replacement. Eight patients were reoperated on for primary tissue failure, and freedom from reoperation for structural valve deterioration was 97.5% +/- 1.2% at 5 years and 95.6% +/- 1.8% at 8 years. Failing aortic bioprostheses were explanted in four patients (0.4%/pt-yr) and mitral bioprostheses in seven (1.6%/pt-yr). No patient whose valve was inserted after the age of 70 had to be reoperated on for structural valve dysfunction. The probability of freedom from thromboembolism after 5 and 8 years of follow-up was 93.1% +/- 1.6% and 92.2% +/- 1.8%, respectively. The prevalence of anticoagulant-related hemorrhage was 0.8%/pt-yr (major 0.6%, minor 0.2%). Anticoagulants had to be maintained in 16.3% of the patients: 5.9% after aortic valve replacement, 35.7% after mitral valve replacement, and 45.8% after aortic and mitral valve replacement, while 80.0% were on a regimen of antiplatelet drug therapy. Prosthetic valve endocarditis happened in five patients (0.3%/pt-yr). Freedom from all valve-related morbidity and mortality, including hospital deaths, was 71.0% +/- 2.7% at 5 years and 58.6% +/- 4.6% at 8 years and was significantly better in the aortic valve replacement group (61.3% +/- 6.6% at 8 years) compared with the mitral valve replacement group (54.4% +/- 7.7% at 8 years; p = 0.04). This study confirms the satisfactory performance of the Carpentier-Edwards valve after aortic valve replacement in elderly patients.(ABSTRACT TRUNCATED AT 400 WORDS)     

Mitral valvuloplasty, a better alternative. Comparative study between valve reconstruction and replacement for rheumatic mitral valve disease

Valvuloplasty is now a well accepted alternative method of surgical treatment of mitral valve disease. To analyse its relative performance in rheumatic valvulopathies, three groups of patients who had mitral valvuloplasty (1980-1984; 241 patients) or mitral valve replacement with mechanical (1980-1984; 386 patients) or biological prostheses (1976-1980; 289 patients) were reviewed. The early mortality was 3.3% for valvuloplasty, 7.8% for mechanical valve replacement and 6.6% for bioprostheses (P less than 0.05). Late mortality occurred at the rate of 2.6% per patient year (15 patients) for valvuloplasty, 5.7% per patient year (70 patients) for mechanical valves and 7.4% per patient year (41 patients) for bioprostheses (P less than 0.01), but valve-related mortality was 1.0% per patient year, 2.5% per patient year and 4.2% per patient year, respectively (P less than 0.01). Reoperation was more frequent after valve replacement with bioprostheses (6.7% per patient year) than after valvuloplasty (4.3% per patient year) and after mechanical valve replacement (1.5% per patient year; P less than 0.02), and was necessitated mainly by residual or recurrent valve dysfunction after valvuloplasty, bland or infected periprosthetic leaks in mechanical valves and degradation of bioprostheses. Valve failure occurred at the rate of 6.1% per patient year for valvuloplasty, 5.7% per patient year for mechanical valves and 11.1% per patient year for bioprostheses (P less than 0.05). In actuarial terms, global survival and survival free from valve related complications were 90% +/- 4% and 70% +/- 6% for patients who had valvuloplasty, 76% +/- 3% and 71% +/- 5% for the mechanical prosthetic replacement group and 62% +/- 7% and 30% +/- 7% for bioprosthetic valve replacement.(ABSTRACT TRUNCATED AT 250 WORDS)     

Surgery for infective endocarditis: determinate factors in the outcome

AIM: The appropriate operative procedures for treatment of infective endocarditis (IE) are still controversial. The authors reviewed their own operative results focusing on preoperative risk factors, intraoperative findings and operative procedures. METHODS: The authors reviewed the cases of 40 adult patients who had undergone surgery since 1999. The mean age of patients was 58 years ranging from 31 to 78 including 30 males and 10 females. Thirty-three patients had native valve endocarditis (NVE) and the remaining seven patients had prosthetic valve endocarditis (PVE). Diseased lesions were located in the mitral valve (MV) in 21 patients, aortic valve in 15 and mitral plus aortic valves in four. Twenty-eight patients (70%) were operated on during the active phase of IE. Streptococcus, Staphyrococcus and Enterococcus species were predominant in the bacterial examination. RESULTS: Active vegetation was observed in 26 (65%) patients. Perforation of valve leaflets was observed in 11 (28%) cases. Changes of native MV leaflet were mild in 8 (40%) out of 20, which seemed to be reparable, while, changes of the native aortic valve leaflet were moderate to severe in 13 (87%) out of 15 patients. Valvular annuls were involved in the infection in 17 (43%) patients. Of the 33 NVE patients, prosthetic valve replacement was performed in 29 patients incduding 19 mitral and 15 aortic valves. MV plasty was performed in 4 patients. In seven PVE patients, prosthetic MV replacement was performed twice. In the aortic group, three patients underwent aortic root translocation, The Ross procedure and standard root replacement were performed respectively. Four patients died after surgery including one NVE case and three PVE cases. Three PVE patients who underwent aortic root translocation or the Ross procedure survived. The hospital mortality of NVE and PVE surgery was 3% and 43% (P<0.01), respectively. By univariant anlysis, there were no significant correlations between operative results and preoperative factors such as bacteria, infective phase, cardiac failure, renal failure, sepsis or brain morbidity. The only significant factor on hospital mortality was PVE. Three patients died of non-cardiac diseases during the follow-up period. CONCLUSION: Operative results of NVE were good after complete resection of infective sites including valve annulus. Both valve replacement and plasty were available for NVE patients. In PVE, new strategies are indispensable and aortic root translocation or the Ross procedure should be a treatment of choice.     

Primary failure of pericardial valvular heterografts

From July 1981 to October 1984, 79 Hancock pericardial valves were implanted in 74 patients surviving the hospital period and with a mean age of 64.2 years. Fifty-two patients underwent aortic valve replacement, 16 had mitral valve replacement, 5 bad a double replacement and 19 associated procedures were performed. The mean survival is 48 months. Until 1st June 1987, 11 primary failures have required reoperation (14.9%), 4 in the mitral position (4.6% patient-years), 7 in the aortic position (3.01% patient-years). The time to reoperation was 48.4 months for the aortic orifice and 36.5 months for the mitral orifice. The lesions most frequently encountered were tears (7 cases), calcifications (5 cases) and stretching of valvular tissue (2 cases); two patients died during the postoperative phase of this operation. Despite the small number of patients followed, this series demonstrates of high incidence of dysfunction due to primary tissue degeneration as, after the 5th year, the actuarial rate of absence of primary lesion is 85.3 +/- 8% with no significant difference between the aortic and the mitral orifices, although dysfunction appears to occur more rapidly in mitral prostheses. These results are much less favourable than those obtained with Ionescu bioprostheses in the aortic position of those obtained with porcine bioprostheses in either position. This justifies very regular clinical and echocardiographic follow-up of patients with Hancock pericardial valvular heterografts.     

Homograft replacement of the mitral valve: eight-year results

OBJECTIVE: The objective of this study was to assess whether the mitral homograft represents a valuable alternative for complete or partial mitral valve replacement. METHODS: Since 1993, 104 patients underwent mitral homograft replacement surgery. The mean age was 38 +/- 15 years. The causes of mitral valve disease were rheumatic disease (n = 76), infective endocarditis (n = 24), and others (n = 4). Sixty-five of these procedures were total homografts, and 39 were partial homografts. RESULTS: The mean follow-up was 52 +/- 35 months (maximum, 117 months). Overall hospital mortality was 4 (3.8%) of 104 patients and 2.5% versus 8.7% for patients without endocarditis and with endocarditis, respectively (P <.19). There were 9 late deaths (cardiac, 4; noncardiac, 5). There have been 5 early (<3 months) and 10 late reoperations. Of the remaining 77 patients, New York Heart Association class was I in 61, II in 14, and III in 2. Four patients had endocarditis, and 5 had an ischemic or hemorrhagic event. Freedom from major cardiac events was 71% +/- 6% at 8 years (partial at 81% vs total at 63%, P <.19). Among patients with a total homograft, freedom from major cardiac events was 61% +/- 9% and 85% +/- 8% at 6 years in patients younger than and older than 40 years, respectively (P =.09). CONCLUSION: The risk of early dysfunction related to a mismatch between the mitral homograft and the patient's valve is the main pitfall of the technique. Beyond that stage, the results were comparable with those of bioprostheses in a cohort of young patients.     

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.     

Comparison of long-term results of Carpentier-Edwards and Hancock bioprosthetic valves

The long-term survival following valve replacement with Carpentier-Edwards or Hancock bioprostheses was compared between the two valve models and between the two groups totaling 407 patients who were discharged after valve replacement beginning in 1974. The two groups of patients were treated in a nonrandomized fashion. The actuarial survival for 299 patients with Carpentier-Edwards valves was 94 +/- 1.5% (+/- standard error) and 93 +/- 1.7% after 5 and 8 years of follow-up, respectively. Comparable figures for 108 patients undergoing valve replacement with Hancock valves were 89 +/- 3.0% and 83 +/- 3.7%, respectively (p = not significant [NS]). The probability of freedom from death and valve removal after 5 and 8 years of follow-up was 91 +/- 1.8% and 79 +/- 4.6%, respectively, with the Carpentier-Edwards valve and 84 +/- 3.5% and 75 +/- 4.3%, respectively, with the Hancock valve (p = NS). An accelerated rate of attrition for both valves was observed in the mitral position. There were no significant differences in actuarial survival between the two valves in the mitral or the aortic position or in the incidence of major valve-related complications.