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Risk factors for atherosclerosis and the degeneration of pericardial valves after aortic valve replacement.

BACKGROUND: Recent studies have demonstrated the influence of atherosclerotic risk factors on the progression of aortic stenosis. We hypothesized that risk factors for atherosclerosis might also be involved in the degeneration of pericardial heart valves and might lead to reoperation as a result of structural valve failure, especially in younger patients with high degeneration rates. METHODS: In 1984 and 1985, 161 patients (74% male; mean age, 54.4 +/- 1.0 years; age range, 17-76 years; median age, 56.5 years) survived isolated aortic (n = 137) or combined aortic and mitral (n = 25) valve replacement with a Hancock extracorporeal pericardial valve. Of these patients, 90 (56%) had reoperations as a result of tissue failure of the aortic valve 5.6 +/- 0.25 years postoperatively. RESULTS: The patient group was split in half at the median age. In patients aged 57 years or younger, diabetes mellitus, female sex, cigarette smoking, and high cholesterol and triglyceride levels were associated with accelerated valve failure. In a multivariate model sex (female, P =.001), smoking (P =.001), diabetes mellitus (P =.020), and cholesterol levels (P =.011) are risk factors for reoperation. Patients without risk factors had reoperation after a mean of 9.25 +/- 0.88 years compared with 4.05 +/- 0.43 years (P =.0002) in patients with 2 or 3 risk factors. CONCLUSIONS: Risk factors of atherosclerosis might play a substantial role in the degeneration of aortic bioprosthetic valves. Lowering of serum lipid levels, smoking cessation, therapy for diabetes, and careful patient selection could be new strategies to postpone degeneration. Younger patients could then possibly benefit from the advantages of bioprostheses.

Adolescent↗

Long-term results of valve replacement with the CarboMedics prosthetic heart valve.

This study examined the long-term results of the CarboMedics prosthetic heart valve. Between July 1990 and May 2000, 256 CarboMedics valve prostheses (120 single aortic, 62 single mitral, and 34 double aortic/mitral) were implanted into 216 patients (mean age 57.8 years). The mean follow-up was 57.7 +/- 36 months (maximum 133 months) with a total of 1,038.4 patient years. Patient survival, including operative deaths, was 85.1% at 10 years. Linearized rates for various complications were thromboembolism 0.39% per patient year, bleeding events 0.39% per patient year; prosthetic valve endocarditis 0.29% per patient year, nonstructural dysfunction 0.87% per patient year, and reoperation 0.39% per patient year. There were no valve thrombosis or structural valve failures in this series. The probabilities of freedom from thromboembolism and reoperation at 10 years were 96.3% and 93.1%, respectively. In conclusion, the CarboMedics valve can be used satisfactorily with a low incidence of thromboembolism and valve thrombosis.

Aortic Valve↗

Percutaneous treatment of valvular heart disease: catheter-based aortic valve replacement and mitral valve repair therapies.

Until recently, percutaneous catheter therapy for valvular heart disease was limited to catheter balloon valvuloplasty for aortic, mitral, or pulmonic stenosis. A number of new approaches to percutaneous valve therapy are now developing rapidly, including methods for catheter-based valve replacement and repair. Stent-mounted valve prostheses have been successfully implanted in the pulmonic and aortic positions. These devices have been constructed using pericardial valve leaflets mounted inside balloon-expandable or self-expanding stents and have been used in patients who are high risk for valve replacement surgery. Percutaneous valve repair is also being developed for mitral regurgitation. Direct leaflet repair and percutaneous annuloplasty are being employed in clinical trials. All the percutaneous approaches are based on existing surgical techniques and offer less invasive alternatives. The era of percutaneous valve therapy has clearly arrived, and ongoing trials will define the clinical role for these new therapies.

Aortic Valve↗

Percutaneous implantation of the CoreValve self-expanding valve prosthesis in high-risk patients with aortic valve disease: the Siegburg first-in-man study.

BACKGROUND: The morbidity and mortality of surgical aortic valve replacement are increased in elderly patients with multiple high-risk comorbid conditions. Therefore, a prospective, single-center, nonrandomized study was performed in high-risk patients with aortic valve disease to evaluate the feasibility and safety of percutaneous implantation of a novel self-expanding aortic valve bioprosthesis (CoreValve). METHODS AND RESULTS: Symptomatic high-risk patients with an aortic valve area <1 cm2 were considered for enrollment. CoreValve implantation was performed under general anesthesia with extracorporeal support using the retrograde approach. Clinical follow-up and transthoracic echocardiography were performed after the procedure and at days 15 and 30 after device implantation to evaluate short-term patient and device outcomes. A total of 25 patients with symptomatic aortic valve stenosis (mean gradient before implantation, 44.2+/-10.8 mm Hg) and multiple comorbidities (median logistic EuroScore, 11.0%) were enrolled. Device success and procedural success were achieved in 22 (88%) and 21 (84%) patients, respectively. Successful device implantation resulted in a marked reduction in the aortic valve gradients (mean gradient after implantation, 12.4+/-3.0 mm Hg; P<0.0001). The mean aortic regurgitation grade was unchanged. Major in-hospital cardiovascular and cerebral events occurred in 8 patients (32%), including mortality in 5 patients (20%). Among 18 patients with device success surviving to discharge, no adverse events occurred within 30 days after leaving the hospital. CONCLUSIONS: Percutaneous implantation of the self-expanding CoreValve aortic valve prosthesis in high-risk patients with aortic stenosis with or without aortic regurgitation is feasible and, when successful, results in marked hemodynamic and clinical improvement.

Aged↗

Time course of aortic valve function and root dimensions after subcoronary ross procedure for bicuspid versus tricuspid aortic valve disease.

BACKGROUND: The freestanding aortic root, which is the currently preferred operative technique for pulmonary autografts, is reported to dilate and potentially promote aortic insufficiency, which has led to a controversial debate on the appropriate surgical technique, especially for congenital bicuspid aortic valve disease. Desirable data on the time course of valve function and root dimensions for the alternative subcoronary technique comparing bicuspid and tricuspid aortic valve disease are scarce. METHODS AND RESULTS: Echocardiographic examinations of 31 patients with congenital bicuspid aortic valve disease (group A; age 50.5+/-11.0 years) and 51 patients with acquired tricuspid aortic valve disease (group B; age 48.1+/-15.7 years) who were operated on between June 1994 and August 1998 were performed twice postoperatively. At first and second follow-up, respectively, maximum (mean) pressure gradients were 6.0+/-2.0 (3.6+/-1.0) and 5.1+/-2.1 (2.9+/-1.1) mm Hg in group A and 6.5+/-3.5 (3.9+/-1.9) and 5.0+/-1.7 (2.9+/-1.0) mm Hg in group B (P>0.05 between groups). In group A, grade 0 aortic insufficiency at first and second follow-up occurred in 8 and 7 patients, respectively, grade 0-I in 12 and 9 patients, grade I in 9 and 11 patients, grade I-II in 1 and 0 patients, and grade II in 1 and 4 patients; in group B, grade 0 aortic insufficiency occurred in 16 and 18 patients, grade 0-I in 16 and 8 patients, grade I in 17 and 21 patients, grade I-II in 0 and 1 patient, and grade II in 0 and 1 patient (P>0.05). Aortic insufficiency decreased in 10 patients (17%). However, there was an overall tendency for aortic insufficiency to increase over time (n=23, 38%), although it remained subclinical. Aortic root dimensions did not differ between groups and were constant during follow-up. CONCLUSIONS: This study provides some evidence that the function of the subcoronary pulmonary autograft in bicuspid aortic valve disease is excellent, with stable root dimensions, and is not different from that of tricuspid aortic valves at least up to 5.5 years postoperatively, which suggests the subcoronary technique should be reconsidered.

Adult↗

[A study of isolated tricuspid valve surgery late after left heart valve operation].

Management of severe tricuspid regurgitation late after left heart valve operation is controversial. There has been reluctance to the operation due to the high risk of repeat operation, coexistent right ventricular dysfunction and pulmonary hypertension. We investigated 6 cases of isolated tricuspid valve surgery (tricuspid valve replacement: 2, tricuspid valve plasty: 4) late after left heart valve operation. Before operation, these patients showed poor general condition (4 cases were NYHA III or IV) but good left ventricular function [mean ejection fraction (EF) 66 +/- 9.6%]. Hospital mortality was 0% and the mean mid-term actual event-free survival over 2 +/- 1.8 years was 80%. Most of patients demonstrated NYHA I and improvement of hepatomegaly after operation. There were many complications in 2 cases that had been performed previous operation more than 20 years before. In summary, the patient who complained symptoms due to right heart ventricular failure and showed good left ventricular function after left heart valve surgery should be considered to undergo tricuspid valve operation before the occurrence of other complications.

Aged↗

Evidence for rheumatic valve disease in patients with severe tricuspid regurgitation long after mitral valve surgery: the role of 3D echo reconstruction.

BACKGROUND AND AIM OF THE STUDY: Although severe tricuspid regurgitation (TR) is a well-recognized, long-term complication of rheumatic mitral valve replacement that impairs the functional results of surgery, its exact basis remains unclear and its management is unsatisfactory. The study aim was to obtain a detailed assessment of tricuspid valve morphology and function using 2D transesophageal echocardiography (TEE) with 3D reconstruction, and to determine long-term clinical outcome in patients after surgery for rheumatic mitral valve disease. METHODS: A total of 42 patients (mean age 50 +/- 10 years) was followed up; 39 patients had mitral replacement and three had valvotomy. Thirty patients had developed impaired exercise tolerance, fluid retention and echocardiographic evidence of severe TR at 8.2 +/- 2.6 years after surgery; the remainder had mild regurgitation. RESULTS: Follow up showed greater mortality in the severe TR group, with approximately 50% survival at 60 months after diagnosis compared with mild TR. None of the patients with severe TR had a dysfunctional mitral prosthesis. In these patients, transthoracic echo-Doppler showed enlarged right atrium and right ventricle, a mean transtricuspid retrograde pressure drop of 15 +/- 4 mmHg and apparently normal leaflet anatomy. Twenty patients (15 with severe TR) underwent a TEE and 3D reconstruction study for further evaluation. Abnormal leaflet anatomy was demonstrated in all patients with severe TR, with restricted leaflet motion in 10, leaflet shortening and thickening in the remainder, and dilatation of tricuspid valve annular insertion suggestive of rheumatic involvement. Although diastolic transtricuspid velocities were increased (peak flow 0.8 +/- 0.1 m/s) in these patients due to increased stroke volume, significant tricuspid stenosis was present in only two cases (mean gradient 4 and 3 mmHg respectively). Histopathology confirmed the presence of leaflet vascularization and extensive fibrosis in two patients who underwent tricuspid valve replacement. CONCLUSION: Rheumatic leaflet involvement contributes to severe TR occurring long after mitral valve replacement, though overt stenosis is uncommon. Knowledge of the structural basis of this condition may thus improve its long-term management, possibly with early tricuspid valve repair.

Adult↗

[Mitral valve and mitral ring movement in mitral stenosis. An ultrasonic study with different valve models (author's transl)].

We constructed three different mitral valve models in order to investigate the different mechanisms which account for the concordant opening and closing movement of the posterior compared to the anterior mitral valve in mitral stenosis. Three different types of movements are possible: a dorso-anterior movement of the mitral ring, opening and closure of the valve itself and a rotation of the entire valve apparatus. Our in-vitro studies showed that the best explanation for the concordant diastolic movement of the posterior valve is given by the assumption that during the early diastolic opening phase of the valves the whole stenotic valve apparatus is rotated upward, i.e. towards the transducer. This rotation, has a higher amplitude compared to the residual downward-oriented opening movement of the posterior valve.

Mitral Valve↗

Results of valve reconstruction for mitral regurgitation secondary to mitral valve prolapse.

Mitral valve prolapse (MVP), often the result of myxomatous degeneration of the mitral valve, is the most commonly known pathologic entity leading to pure mitral regurgitation (MR). Reconstruction of the mitral valve rather than replacement is particularly applicable to this pathologic defect, but is not often used in the U.S. Experience with reconstruction of the mitral valve for MR secondary to MVP during the period January 1970 to January 1984 was reviewed. A total of 479 patients with mitral valve disease underwent operation during this period, 82 (17%) of whom had MR secondary to MVP. Thirty-one patients (6%) had valve reconstruction by a technique of leaflet plication and posteromedial anuloplasty. Eleven of these patients had associated cardiac disease requiring correction: 2 requiring aortic valve replacement and 9 requiring coronary artery bypass grafting procedures. One hospital death (3%) and 6 late deaths (19%) occurred, of which only 3 were related to cardiac factors. Major complications included recurrent MR in 5 patients and cerebral embolus in 1 patient. The adjusted 5-year survival rate was 89 +/- 6 (mean +/- standard error of the mean), and the overall survival rate of patients free of cardiac-related complications was 73 +/- 9%. Thus, reconstruction of the mitral valve is a highly effective surgical approach to the management of symptomatic patients with MR secondary to MVP, and its use is favored over replacement in the management of these patients.

Actuarial Analysis↗

Determination of aortic valve orifice area in aortic valve stenosis by two-dimensional transesophageal echocardiography.

Two-dimensional transesophageal echocardiography was used to measure aortic valve orifice area in 24 patients with aortic valve stenosis (AS) and 15 patients without aortic valve disease. Using transesophageal echocardiography, orifice area could be measured in 20 of 24 patients with AS. With transthoracic echocardiography, orifice area could be determined in only 2 of 24 patients. In patients with AS, orifice area determined by transesophageal echocardiography was 0.75 +/- 0.34 cm2 and that calculated with Gorlin's formula was 0.75 +/- 0.32 cm2. In normal aortic valves, orifice area was 3.9 +/- 1.2 cm2 by transesophageal echocardiography. A good correlation was demonstrated between aortic valve orifice area determined using transesophageal echocardiography and calculated orifice area using Gorlin's formula in patients with AS: r = 0.92, standard error of estimate = 0.14 cm2. The absolute difference between orifice area measured with both methods ranged from 0.0 to 0.4 cm2 (mean 0.09 +/- 0.1). In 4 patients orifice area could not be determined with transesophageal echocardiography. The orifice could not be identified in 2 patients because an appropriate cross-sectional view of the aortic valve could not be achieved and in 2 patients with pinhole stenosis (aortic valve orifice area 0.3 cm2). These data show that aortic valve orifice area can be measured reliably using 2-dimensional transesophageal echocardiography.

Aged↗

Doppler echocardiographic study of porcine bioprosthetic heart valves in the aortic valve position in patients without evidence of cardiac dysfunction.

To study the natural history of the hemodynamic performance of bioprosthetic heart valves, Doppler echocardiograms were recorded in a group of clinically stable patients at 2 and 5 years after replacement of native aortic valves with bioprosthetic valves. Eighteen patients completed a 2-year and 26 patients a 5-year follow-up examination. The effective orifice areas of identical models of bioprosthetic valves (Hancock II) were determined in vitro in a left-sided heart pulse duplicator system. In vivo Doppler-derived effective orifice areas were compared with the in vitro measurements for the same valve size. At both the 2- and 5-year follow-up examinations, the Doppler-derived effective orifice area was significantly less than the in vitro area (p less than 0.0001 at each interval). Ten of 16 valves evaluated serially decreased greater than 0.20 cm2 in the Doppler-derived effective orifice area between studies. The mean decrease in effective orifice area in valves evaluated serially was 0.25 +/- 0.29 cm2 (p less than 0.005). The peak transaortic gradient increased from 21 +/- 6 to 27 +/- 8 mm Hg (p less than 0.01). The mean transaortic gradient increased from 12 +/- 4 to 15 +/- 7 mm Hg (p less than 0.05). It is concluded that serial Doppler echocardiographic studies demonstrate a deterioration in the hemodynamic performance of bioprosthetic valves over time in patients with no symptoms or signs of valvular dysfunction and that Doppler echocardiography may be useful for identifying subclinical bioprosthetic valvular dysfunction.

Adult↗

Thromboembolic risk and late survival after mitral valve replacement with the St. Jude Medical valve.

From January 1979 to December 1990, 397 consecutive patients (mean age, 55 +/- 11 years) underwent mitral valve replacement with the St. Jude Medical valve. Associated procedures performed were 174 multiple valve replacements, 24 coronary artery bypass graftings, 25 tricuspid repairs, and 13 left ventricular myectomies. The continuous intravenous administration of heparin was started on the first postoperative day and maintained until effective oral anticoagulation, started on the seventh day, was achieved (INR, 3 to 4.5). Follow-up consisted of 2,402 patient-years (pt-y) (mean, 6.1 +/- 0.2 years) and was 97% complete. The early (30-day) mortality was 3.5%; the 5-year and 10-year actuarial survivals were 86% +/- 4% and 73% +/- 6%, respectively. Survival was less in patients who had been in an advanced preoperative functional class (p = 0.02) and in those who underwent multiple valve replacements (p = 0.05). The 5-year and 10-year survivals in patients who underwent isolated mitral valve replacement and who were in preoperative New York Heart Association functional class II and III, were 90% +/- 5% and 82% +/- 7%, respectively. The early and late mortality and the incidence of deaths resulting from heart failure and sudden deaths were higher in patients who had undergone multiple valve replacements (p = 0.05). In terms of all deaths, 47% (36/77) were valve related (including 12 sudden deaths, 0.50%/pt-y). Thromboembolic complications occurred in 44 patients, and these were broken down as follows: embolism, 1.46%/pt-y, and valve thrombosis, 0.37%/pt-y.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Readily available porcine aortic valve matrices for use in tissue valve engineering. Is cryopreservation an option?

The clinical use of acellular biological valves as scaffolds in tissue valve engineering would require them to be readily available. This study examines the feasibility of cryopreserving porcine aortic valve matrices for use in tissue valve engineering. Matrices prepared using an enzymatic-detergent decellularization protocol were examined before and after cryopreservation. The biochemical status of tissues were evaluated by collagen and uronic acid (proteoglycan) determination and their mechanical properties were determined using a burst test. The histological and ultrastructural properties were evaluated by light and electron microscopy. Cryopreservation did not significantly affect the collagen and uronic acid content of aortic leaflet matrices. Histological and ultrastructural sections, however, confirmed extensive disruption of the extracellular collagen matrix and inter-fibrillar proteoglycan associations following cryopreservation. Although neither the breakage force nor the maximum force at failure was significantly different in matrices before and after cryopreservation, the strain observed in matrices was significantly higher after cryopreservation. To our knowledge this is the first study to investigate the effects of cryopreservation on aortic valve matrices. Cryopreservation did not significantly alter the biochemical properties of porcine aortic valve matrices. Nevertheless, cryopreservation had significant adverse effects on the structural and mechanical properties of matrices. Cryopreserved matrices showed significantly higher strain when stressed compared to non cryopreserved matrices. While, theoretically matrices are only expected to be functional for a limited time until regenerated in vivo, further mechanical testing is necessary to evaluate the effects of these changes on the durability of porcine aortic valve matrices for use in tissue valve engineering.

Animals↗

Simultaneous Doppler and catheter transvalvular pressure gradients across St Jude bileaflet mitral valve prosthesis: in vivo study in a chronic animal model with pediatric valve sizes.

A mixture of valve types has been used in previous in vivo studies to assess the accuracy of Doppler echocardiography compared with catheter-measured pressure gradients across prosthetic mitral valves. However, limited data exist regarding the most commonly used bileaflet mechanical valve. We studied 14 sheep with St Jude Medical mechanical mitral valves. Continuous wave Doppler data were obtained across each of the 3 valve orifices. Hemodynamic data were obtained simultaneously by direct measurements with catheters. Valve sizes commonly used in the pediatric population in the mitral position (23 mm, 25 mm, and 27 mm) were studied. Linear regression analyses of Doppler-predicted versus catheter-measured gradients provided correlation coefficients ranging from 0.75 to 0.91. Agreement analysis demonstrated a scatter of Doppler data about the regression line. Although a reasonably good correlation of Doppler-predicted peak and mean pressure gradients across bileaflet mechanical valves exists in the mitral position, caution is needed when this method is applied to patients. Doppler overestimation was greatest across the 23-mm valves. Analyses of the specific orifice interrogated demonstrated higher estimated pressure gradients across the central orifice compared with the side orifices.

Animals↗

Tissue engineering of heart valves by recellularization of glutaraldehyde-fixed porcine valves using bone marrow-derived cells.

To increase the biocompatibility and durability of glutaraldehyde (GA)-fixed valves, a biological coating with viable endothelial cells (ECs) has been proposed. However, stable EC layers have not been formed successfully on GA-fixed valves due to their inability to repopulate. In this study, to improve cellular adhesion and proliferation, the GA-fixed prostheses were detoxified by treatment with citric acid to remove free aldehyde groups. Canine bone marrow mononuclear cells (MNCs) were differentiated into EC-like cells and myofibroblast-like cells in vitro. Detoxified prostheses were seeded and recellularized with differentiated bone marrow- derived cells (BMCs) for seven days. Untreated GA-fixed prostheses were used as controls. Cell attachment, proliferation, metabolic activity, and viability were investigated and cell-seeded leaflets were histologically analyzed. On detoxified GA-fixed prostheses, BMC seeding resulted in uninhibited cell proliferation after seven days. In contrast, on untreated GA-fixed prostheses, cell attachment was poor and no viable cells were observed. Positive staining for smooth muscle a-actin, CD31, and proliferating cell nuclear antigen was observed on the luminal side of the detoxified valve leaflets, indicating differentiation and proliferation of the seeded BMCs. These results demonstrate that the treatment of GA-fixed valves with citric acid established a surface more suitable for cellular attachment and proliferation. Engineering heart valves by seeding detoxified GA-fixed biological valve prostheses with BMCs may increase biocompatibility and durability of the prostheses. This method could be utilized as a new approach for the restoration of heart valve structure and function in the treatment of end-stage heart valve disease.

Actins↗

Culture results of heart valves resected because of streptococcal endocarditis: insights into duration of treatment to achieve valve sterilization.

OBJECTIVES: To analyse the culture results of heart valves removed following streptococcal endocarditis in order to gain insight into the duration of treatment required for valve sterilization. PATIENTS AND METHODS: Retrospective review of 131 episodes of streptococcal endocarditis: 94 due to alpha-haemolytic streptococci; 15 due to beta-haemolytic streptococci; 10 due to nutritionally deficient streptococci; eight due to the Streptococcus anginosus group and four due to Streptococcus pneumoniae. Patients had their valves removed during antimicrobial treatment. Culture results were analysed with respect to duration of treatment before surgery. RESULTS: For alpha-haemolytic streptococci, 17 (18%) valves were culture-positive and 77 (82%) culture-negative after a median (range) of 4 (1-20) and 16 (4-58) days of treatment, respectively, P < 0.001. For beta-haemolytic streptococci, two valves (13%) were culture-positive; both patients had received < or = 4 days of treatment. Four patients (40%) with nutritionally deficient streptococci were culture-positive, and had received < or = 8 days of treatment. For the S. anginosus group, two valves (25%) were culture-positive; both patients had received < or = 4 days of treatment before operation. Overall, only one of 131 (0.8%) valves was culture-positive after 14 days of treatment. All valves infected with beta-haemolytic streptococci, nutritionally deficient streptococci and the S. anginosus group, who were treated for more than 8 days before surgery, were culture-negative. CONCLUSIONS: Our findings support current treatment guidelines for endocarditis caused by alpha-haemolytic streptococci. We suggest that the recommended duration of treatment for endocarditis resulting from other streptococci may be excessive and treatment trials evaluating 2 and 4 week regimens are justified.

Adult↗

Doppler echocardiographic assessment of the valve area in patients with atrioventricular valve stenosis by application of the continuity equation.

The orifice area was non-invasively assessed in 19 patients with mitral or mitral and tricuspid stenosis by combined cross-sectional and Doppler echocardiography. Stroke volume was calculated as the product of aortic or pulmonic cross-sectional area and the time velocity integral of the flow across that valve, and the stenotic valve area was obtained as the stroke volume divided by the time velocity integral of the stenotic valve. In addition, the mitral valve area was estimated by the pressure half-time method of Hatle et al. The non-invasive determinations were compared with those calculated by the Gorlin formula at cardiac catheterization. The valve area obtained by combined cross-sectional and Doppler echocardiography showed a close correlation with the Gorlin area, r = 0.90, SEE = 0.13 cm2, n = 20. In contrast, the valve area estimated by the pressure half-time method showed only a moderate correlation with the Gorlin area, r = 0.68, SEE = 0.38 cm2, n = 18, and estimates by this method tended to significantly overestimate the Gorlin area. In conclusion, non-invasive valve area determinations based on combined cross-sectional and Doppler echocardiography can be used to accurately quantify the severity of the lesion in patients with atrioventricular valve stenosis, while determinations by the pressure half-time method may show errors of a magnitude that limits its clinical applicability.

Aged↗

Surgical treatment of prosthetic valve endocarditis with homograft aortic valve replacement.

This article presents the University of Alabama experience with homograft aortic valve replacement for prosthetic valve endocarditis. Of 117 patients who have undergone homograft aortic valve replacement since 1981, there has been a total of 22 patients who underwent operation for endocarditis. Sixteen were isolated valve replacements, three combined with other procedures, and three were aortic root replacements. When placed in a setting of active endocarditis, there have been no reoperations for endocarditis of the homograft valve. Surgical techniques are presented for the freehand sewn homograft as well as aortic root replacement. Prosthetic valve endocarditis is a highly lethal event and when aortic valve replacement is advised in this setting, we believe a homograft aortic valve should be implanted whenever possible.

Aortic Valve↗