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The purpose of this study was to review the results of mitral and tricuspid valve replacement with mitral valve homograft. Twenty-two mitral homografts were used to replace cardiac valves in 20 patients. The mitral valve was replaced in 18 patients, applying the method described by Acar. The tricuspid valve was replaced in 2 patients, attaching one papillary muscle of the graft to the anterior papillary muscle and bringing the other papillary muscle of the graft through a tunnel in the anterior wall of the right ventricle. A concomitant Maze III procedure was performed in 3 patients. Accuracy of the repair was confirmed by intraoperative echocardiography. All patients survived operation and are currently alive. One patient was lost to follow-up. Patients have been followed for up to 3.25 years. All patients have good exercise ability (NYHA class I). Five homografts (25%) have been explanted from the mitral position and one from the tricuspid position. All events occurred during the first year after reoperation. Cardiac valve replacement with mitral valve homograft may be accomplished safely. A technically good operation does not guarantee that the valve will remain competent and an unacceptably high early explant rate may be expected. Use of mitral valve homograft for cardiac valve replacement should be restricted to young patients in whom anticoagulant medication is not indicated or undesirable and for those with resistant infection.

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Although stentless aortic bioprostheses are associated in general with excellent hemodynamics, a subset of patients exhibit high early postoperative gradients. The present study was performed to evaluate the prevalence and impact of suboptimal hemodynamics early after stentless tissue aortic valve replacement. The early postoperative peak transvalvular to peak left ventricular (LV) outflow tract velocity ratio was > or = 3.0 in 44 (6.7%) of 658 patients in the multicenter, long-term study of the Freestyle stentless aortic valve. Mean gradient, effective orifice area (EOA), and LV mass index were compared between these patients and a control group of 44 patients matched for age, sex, valve size, and implant technique. High velocity ratio was associated with female sex (63.6% v 42.8%, P =.01), smaller valve size (77.3% v 45.3%, < or = 23 mm, P =.0004), and use of the modified subcoronary rather than full root implant technique (90.9% v 70.2% modified subcoronary, P =.01). Mean gradient was significantly higher (P <.05) and EOA lower (P <.05) early postoperative and throughout follow-up among patients with high velocity ratio. LV mass index decreased across time among both groups; patients with high velocity ratio tended to have higher LV mass index with less complete LV mass regression, although the difference did not reach statistical significance. In conclusion, there was a 6.7% incidence of hemodynamics suggestive of significant aortic stenosis early after implantation of a Freestyle stentless aortic valve. Gradients decreased and EOA increased in the first months after surgery, although they remained less favorable. Multiple factors likely play a role in early suboptimal hemodynamics following stentless tissue aortic valve replacement, including factors related to patient population, valve size, implant modality, and implant technique.

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At our center we have encouraged consideration of the Maze procedure over noncurative therapies for atrial fibrillation, particularly in patients who have other indications for cardiac surgical intervention. As a result, 78 of the 99 Maze procedures we have performed since 1993 have involved combined procedures. These combined operations included procedures on 1 or more valves in 69 of 78 patients (88%). The unmodified "cut-and-sew" Maze-III technique was used in all patients. There has been no operative mortality, and the median postoperative stay has been 7 days. Cure of atrial fibrillation has been observed in 97% of patients, and pacemaker implantation was required for sick sinus syndrome in 6%. Our results favor broader use of the Maze procedure for symptomatic atrial fibrillation and support use of the original Maze-III technique as the procedure of choice.

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BACKGROUND: Mitral valve disease is often accompanied by atrial fibrillation, which may compromise the patient even after the valvular lesion has been repaired. METHODS: Three patients with rheumatic type mitral valve disease and chronic atrial fibrillation were treated by mitral valve replacement with cryopreserved mitral valve homograft and Maze III procedure, as a method to relieve both the valvular pathology and the rhythm disorder. The patients' clinical courses have been followed for up to 1 year after operation. RESULTS: All patients survived operation, and all have normal sinus rhythm. None are taking cardiac medications. CONCLUSIONS: Long-term treatment with warfarin should not be required, and other cardiac medicines may be eliminated following mitral valve replacement with homograft combined with Maze III procedure.

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Simple and reproducible methods for accurate restoration of aortic root dimensions during aortic valve-sparing operations are described. The methods are based on choice of an appropriate size vascular graft based on the measured or desired diameter of the aortic annulus.

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Endocarditis represents a difficult medical problem that must occasionally be treated surgically. Constitutional symptoms of infection are important and are usually the reason that the patient seeks medical attention. Fever is the most common sign of infective endocarditis and a heart murmur, which changes in character or is new, is a significant hallmark. The diagnosis for infective endocarditis is made by high index of suspicion in a patient with valvular heart disease or a prosthetic heart valve and in the presence of fever and a cardiac murmur. A positive blood culture is the hallmark of the diagnosis. The absolute indications for operative intervention are congestive heart failure, unstable prosthetic valve, uncontrolled infection, and relapse after optimal therapy (prosthetic valve). Relative indications for operative intervention are perivalvular extension of the infection, staphylococcal infection of a prosthesis, persistent fever (culture negative), large vegetation, or relapse after optimal therapy (native valve). The principles of surgical management are to remove all infected tissue by thorough debridement back to normal tissue. This is combined with replacement of damaged valves and repair of associated defects. The mortality after operation for infective endocarditis is 15-20%. Late survival after operation for infective endocarditis on a native heart valve is 70-80% at 5 years. Survival falls to 50-80% at 5 years for surgery on an infected prosthetic heart valve.

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BACKGROUND AND AIM: Operations on cardiac valves are being performed more frequently through smaller incisions than traditional midline sternotomy. A variety of alternate incisions have been used, but most of the interest appears to focus on partial sternotomy. The purpose of the study was to review results using a partial lower sternotomy for cardiac valve operations. METHODS: A standard partial lower one-half or two-thirds sternotomy was used for cardiac valve operations in 112 patients. The sternum was divided transversely in the third or second intercostal space and vertically from that point through the xyphoid process. Standard instruments and retraction devices were used. This incision provided adequate exposure for even complex operations to be performed. Small cannulae were placed into the aorta and heart through the primary incision for cardiopulmonary bypass. Vacuum-assisted venous drainage was used. RESULTS: Seventy-four single valve operations were performed. There were 35 double valve and 5 triple valve operations (35.4%) performed. Operative mortality (5.3%) and major complication rates were comparable to full the sternotomy approach. CONCLUSIONS: Partial sternotomy (lower half) provides a smaller incision through which virtually all cardiac valve operations may be performed. Results achieved with this approach are similar to those associated with full sternotomy. The smaller incision is appreciated by patients.

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BACKGROUND: Previous midterm experience with the composite spiral saphenous vein graft to bypass the obstructed superior vena cava (SVC) has been favorable. This study looks at the long-term results in patients followed for up to 23 years. METHODS: Sixteen patients aged 17 to 68 years had operation for obstruction of the SVC with SVC syndrome caused by benign disease. Eleven patients had fibrosing mediastinitis with or without caseous necrosis, 4 had thrombosis caused by a catheter or a pacemaker electrode, and 1 had spontaneous thrombosis. All operations were performed using a composite spiral vein graft constructed from the patient's own saphenous vein. Graft diameter ranged from 9.5 to 15.0 mm. Ten grafts were from the left innominate vein, and six grafts were from the right or left internal jugular vein. The grafts were placed to the right atrial appendage in all patients except 1. Follow-up extends from 1 month to 23 years 8 months (mean follow-up, 10.9 years). RESULTS: Fourteen of 16 grafts remain patent for up to 23 years, and all patients but 1 are free from SVC syndrome. One patient required revision of the graft for thrombosis 4 days after operation. Two grafts closed during the first year after operation: one because of recurrence of spontaneous venous thrombosis and the other because of aggressive fibrosing mediastinitis requiring operation for graft revision three times over a 12-year period prior to death. CONCLUSIONS: These data demonstrate that a spiral vein bypass graft for treatment of the obstructed SVC relieves SVC syndrome and has excellent long-term patency.

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BACKGROUND: The purpose of this study was to determine if hearts could be successfully reanimated after death in an extra corporeal circuit. METHODS: Reanimation of pig and dog heart was accomplished in an extra corporeal circuit after death by lethal injection of Pentothal (euthanasia). A total of 42 experiments were performed. RESULTS: The most successful combination included enhancement of the cardioplegic and reperfusion solutions with amino acids, calcium and magnesium ions, and using the animals own drug free blood in the reperfusion solution. Successful resuscitation of the heart was accomplished after ischemic cold storage as long as 9 hours after death. A beating heart was sustained by the extra corporeal circuit for over 10 hours (635 minutes). CONCLUSIONS: In summary, successfully reanimation of the heart in an extra corporeal circuit is possible when cold cardioplegic solution is administered 10-35 minutes after death by lethal injection of Pentothal.

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The Medtronic Freestyle aortic root bioprosthesis has been implanted in patients since August 1992. This study reviews clinical and echocardiographic results at midterm (5 years) after implantation. The Freestyle bioprosthesis was implanted in 1,100 patients in a 21-center Food and Drug Administration clinical trial from August 1992 to October 1998. The device was implanted (1) as a subcoronary valve replacement, (2) as a complete aortic root replacement (full-root), or (3) as a root inclusion. Patients were followed annually by clinical examination and echocardiography. There were 47 deaths early after operation (7.1%). There were 2,478 patient-years of follow-up during which there were 99 deaths or 4.0/pt.-yr. Before implantation, 73% of patients were in New York Heart Association functional class III or IV. After operation, 95% were in class I or II. Transvalvular gradient 4 years after operation was low (7.5+/-5.3 mm Hg) for all valve sizes (subcoronary implant). Small valves (19 and 21 mm) had mean gradients (10.2+/-3.0, 9.1+/-4.4 mm Hg). There was no or mild valve insufficiency in 98% of patients. Actuarial analysis at 5 years showed the rate for freedom from thromboembolism of 86% in subcoronary implant and 93% in full root replacement. Freedom from endocarditis was 98%. Freedom from reoperation for explant of the valve highest in patients having full root replacement (98%) and lower with root inclusion (94%). There were 20 bioprostheses explanted; 10 for endocarditis, 8 for technical reasons, and 2 for structural deterioration. The Medtronic Freestyle bioprosthesis (1) has excellent hemodynamic performance, (2) techniques for insertion that result in a competent valve, (3) low rates of thromboembolism and endocarditis, and (4) a rare rate of structural deterioration at 5 years.

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The purpose of this study was to review the results of mitral valve replacement with mitral valve homograft, applying the method described by Acar, to determine if the method could be reproduced and was safe to use. Fourteen patients had replacement of the mitral valve with homograft. The diseased valve was excised and replaced with a cryopreserved homograft. The papillary muscles of the graft were attached to the papillary muscles of the patient in side-to-side fashion, using multiple stitches of fine monofilament suture. The annulus of the graft was attached to the patient annulus by continuous suture. The repair was supported by annuloplasty ring. All patients had intraoperative echocardiography. Patients were monitored clinically for up to 1.5 years. There were five men and nine women ranging in age from 16 to 70 years (mean = 43 years). Seven had rheumatic, six had degenerative, and one congenital morphology. Concomitant Maze III procedure was performed in three patients. All patients survived and are currently alive and in New York Heart Association functional class I. Thirteen patients have normal sinus rhythm. Only one patient has intermittent atrial fibrillation and is taking digoxin and warfarin. One patient had dehiscence of the recipient papillary muscle that required reoperation for mitral valve replacement with prosthesis. Three patients have moderate mitral valve regurgitation. Mitral valve replacement with homograft may be accomplished safely and reproducibly using the Acar method. Good short-term functional results and maintenance of normal sinus rhythm may be expected. Anticoagulant therapy should not be required.

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A technique is described in which most, if not all, cardiac operations may be performed through a standard small incision. A midline, lower half sternotomy is used. This provides traditional exposure of the heart and allows the surgeon to directly visualize the operating field and use familiar instruments. The complete spectrum of coronary revascularization and cardiac valve operations has been performed through this less-invasive incision.

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OBJECTIVE: Cryopreserved aortic allograft can be used for aortic valve replacement in congenital, rheumatic, degenerative, and infected native valve conditions, as well as failed prosthetic valves. This study was conducted to determine the long-term results of aortic valve replacement with cryopreserved aortic allografts. METHODS: Aortic valve replacement with cryopreserved aortic allografts was performed in 117 patients from July 1985 until August 1996. All patients requiring aortic valve replacement regardless of valve disease were considered for allograft replacement; the valve was preferentially used in patients under age 55 years and in the setting of bacterial endocarditis. Four operative techniques involving cryopreserved aortic allografts were used: freehand aortic valve replacement with 120-degree rotation, freehand aortic valve replacement with intact noncoronary sinus, aortic root enlargement with intact noncoronary sinus, and total aortic root replacement. Valve function was assessed by echocardiography during the operation in 78 patients (66%) and after the operation in 77 patients (65%). RESULTS: One-hundred eighteen aortic valve replacements with cryopreserved aortic allografts were performed on 117 patients; mean age was 45.6 years (range 15 to 83 years) and mean follow-up was 4.6 years (range up to 11 years). Intraoperative echocardiography disclosed no significant aortic valve incompetence. There were four operative deaths (3%) and seven late deaths; freedom from valve-related mortality at 10 years was 9:3% +/- 4.55%. New York Heart Association functional status at latest follow-up was normal in 98 (94%) patients. On postoperative echocardiography, 90% had no or trivial aortic valve incompetence. Freedom from thromboembolism at 10 years was 100% and from endocarditis, 98% +/- 2.47%. Seven (6%) patients required valve explantation, four for structural deterioration. At 10 years, freedom from reoperation for allograft-related causes was 92% +/- 3.47%. CONCLUSIONS: Aortic valve replacement with cryopreserved aortic allografts can be performed with low perioperative and long-term mortality. Most patients have excellent functional status, and reoperation for valve-related causes is unusual. Aortic valve replacement with cryopreserved aortic allografts demonstrates excellent freedom from thromboembolism, endocarditis, and progressive valve incompetence.

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BACKGROUND: Aortic prosthetic devices offer limitations that make them less than optimal valve substitutes because the vast majority are innately obstructive, especially at increased levels of hemodynamic function. The present study is designed to demonstrate the hemodynamics of the pulmonary autograft in 11 conditioned athletes who have undergone the Ross (pulmonary autograft) procedure. Data was compared to a group of 13 age-matched "normal athletes." METHODS: All the Ross athletes had undergone the autograft procedure using the root replacement technique and were at least 3 months into their postrecovery phase. All athletes (both normal and Ross) underwent resting transthoracic echo followed by maximal exercise stress test (modified Bruce protocol) to exhaustion. Post-operative transesphogeal echocardiogram obtained within 90 seconds documented aortic valve gradient and velocity across the aortic valve. RESULTS: In the Ross athlete group, maximum heart rate was 188 beats per minute, peak aortic valve gradient at rest (mm Hg) 7.69 (mean), velocity across the aortic valve at rest (cm per second) 129.40 (mean), peak aortic valve gradient at maximal exercise (mm Hg) 16.30 (mean), velocity across the aortic valve at maximal exercise (cm per second) 190.00 (mean). In the normal athlete group, maximum heart rate was 176 beats/minute, peak aortic valve gradient at rest (mm Hg) 5.97 (mean), velocity across the aortic valve at rest (cm per second) 120.54 (mean), peak aortic valve gradient at maximal exercise (mm Hg) 14.61 (mean), velocity across the aortic valve at maximal exercise (cm per second) 190.23 (mean). CONCLUSION: The pulmonary autograft exhibits hemodynamic characteristics similar to the normal human aortic valve under conditions of enhanced cardiac output.

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The technique for replacement of the mitral valve with a mitral valve homograft is described. Principles include side-by-side approximation of the papillary muscles using multiple stitches of fine monofilament suture, direct attachment of the annulus of the mitral homograft to the annulus of the patient, and support of the repair by remodeling annuloplasty ring.

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BACKGROUND: The Medtronic Freestyle aortic root bioprosthesis is a complete porcine aortic root to allow implantation (1) as a subcoronary valve replacement by removing graft sinus aorta, (2) as a cylinder with the sinotubular junction intact within the aorta (root inclusion), or (3) as a complete aortic root replacement. The choice among the three implant techniques depends on surgeon preference or upon the pathology encountered. The advantages and differences among the three implant techniques are examined. METHODS: The Medtronic Freestyle bioprosthesis was implanted in 1163 patients in a Food and Drug administration (FDA) clinical trial between August 1992 and October 1997. There were 21 centers in the international trial using a single data repository. Clinical data was collected prior to and at operation, at 3 to 6 months and annually. The data were compiled and statistical analysis performed at the data center. RESULTS: Patients having subcoronary valve implants were older (80% > 65 years) and aortic occlusion time was about 20 minutes less than the other methods. Patients having aortic root replacement presented with more aortic valve insufficiency (20%). Pathology of the aortic root and ascending aorta requiring repair was 26%, and larger (27 mm) valves were used in 40% of patients. Risk of operation was lowest (5.0%) with subcoronary valve implants and highest (11.7%) with root replacement technique. Thromboembolism was higher, early and late, with root inclusion (3.0, 3.9%/patient per year) and root replacement (3.2, 3.0%/patient per year) than for subcoronary implants (1.8, 1.6%/patient per year). There were more patients taking warfarin at the 4-year point with root inclusion (20%) or root replacement techniques (24%) than among patients having subcoronary implants (14%). Explants of the valve occurred in 2% of patients, none of whom had aortic root replacement. CONCLUSIONS: The Medtronic Freestyle bioprosthesis is an effective and versatile device for replacement of the aortic valve. It offers implant techniques that can treat the aortic root pathology encountered at surgery and allows the operation to proceed according to surgeon preference.

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OBJECTIVE: This study evaluates the initial results for safety and efficacy of aortic valve replacement (AVR) using the Medtronic Freestyle Bioprosthesis. METHODS: One hundred three patients underwent AVR with the Medtronic Freestyle Bioprosthesis over a 40-month period. There were 59 male and 44 female patients with a mean age of 74 years (range 36 to 88 years). Valve size ranged from 19 to 27 mm, and all valves were implanted using a freehand subcoronary technique. Anticoagulation with coumadin was only used for atrial fibrillation. Aspirin was given to patients with associated coronary artery disease. Echocardiography to assess transvalvular pressure gradient and effective valve orifice area was performed at discharge, 3 to 6 months, 1 year, and then annually. RESULTS: There were 4 (3.9%) deaths within 30 days of operation and 5 (4.9%) late deaths. Two (1.9%) deaths were valve-related, one from commissural dehiscence and one from bacterial endocarditis. Three (2.9%) deaths, two early and one late, were from other cardiac causes. The remaining deaths were from noncardiac causes. Five (4.9%) patients suffered a thromboembolic event, two had permanent neurological deficits, two had transient neurological events, and one had coronary artery occlusion. Mean transvalvular gradient assessed by echocardiography was low at all time intervals: discharge (12.8 mmHg), 3 to 6 months (11.3 mmHg), 1 year (12.0 mmHg), and 2 years (11.6 mmHg). Mean effective valve orifice area was good at all time intervals: discharge (1.4 cm2), 3 to 6 months (1.5 cm2), 1 year (1.6 cm2), and 2 years (1.6 cm2). Of the 38 patients assessed by echocardiography at 1 year, 33 (87%) had no or trivial valve incompetence and the remainder had mild valve incompetence. CONCLUSIONS: Aortic valve replacement with the Medtronic Freestyle Bioprosthesis has a low incidence of early valve-related mortality and thromboembolism. The bioprosthesis demonstrates good hemodynamic performance even in small diameters and is particularly well suited for older patients and the small aortic root.

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