Atsushige Oryoji

Long-term results of valve replacement with the St. Jude Medical valve.

Between 1980 and 1992, 908 patients underwent single aortic (n = 178), single mitral (n = 577), or double aortic and mitral (n = 153) valve replacement with the St. Jude Medical valve at our hospital. There were 392 male patients and 516 female patients whose ages ranged from 1.2 to 74 years (mean, 52 years). The early mortality rate was 5.0% (45 patients). A 94% complete follow-up was accomplished for 863 patients who were discharged from the hospital (4682.3 patient-years). Sixty-nine of these patients died, for a late mortality rate of 8.0%. Fifty-two patients, including four patients (0.3%/100 patient-years) had anticoagulant-related hemorrhage, 4(0.1%/100 patient-years) had prosthetic valve endocarditis, 11 (0.2%/100 patient-years) had nonstructural valve dysfunction, and 16 (0.3%/100 patient-years) underwent reoperation. There were no structural valve failures in this series. The total number of valve-related deaths was 22. Of those patients who survived, 98% were in New York Heart Association functional class I or II at the date of the last follow-up. The probabilities of freedom from thromboembolism and anticoagulant-related hemorrhage at 10 years were 94% +/- 2% and 97% +/- 2% in aortic valve replacement, 89% +/- 2% and 98% +/- 4% in mitral valve replacement, and 89% +/- 6% and 92% +/- 6% in double valve replacement, respectively. Significant hemolysis related to the St. Jude Medical valve occurred in 8 of the 577 patients who received mitral valve replacement in our early experience, and modifying the valve orientation appeared to play an important role in reducing hemolysis. The event-free rate, including all complications and late deaths, at 10 years was 75% +/- 7%, 74% +/- 3%, and 81% +/- 6% in aortic valve replacement, mitral valve replacement, and double valve replacement, respectively. On the basis of these results, the St. Jude Medical valve seems to be an excellent mechanical valve in terms of durability and low thrombogenicity and remains our prosthetic valve of choice when valve replacement with a mechanical valve is indicated.

Tricuspid valve replacement with the St. Jude Medical valve: 19 years of experience

OBJECTIVE The choice of the valve substitute in the tricuspid position remains controversial. A St. Jude Medical valve is a choice of valve substitute and its lower thrombogenicity and excellent hemodynamic performance have been reported even in the tricuspid position. However, little is known of the long-term durability of the St. Jude Medical valve in the tricuspid position. Our long-term experience of tricuspid valve replacement showed the higher thrombogenicity than we had expected, therefore, this study was done to reconsider our strategy for valve choice. METHODS This study reviewed 23 patient who underwent 25 tricuspid valve replacements with the St. Jude Medical valves from 1980 to 1997. The mean age was 40 years. Eleven patients (48%) were men. There were four in-hospital deaths (17%). The remaining 19 patients were all alive and followed from 2.2 to 19.0 years (mean 11.8 years). RESULTS The overall survival, including hospital mortality, was 83%, 10 and 15 years after surgery. Valve thrombosis occurred in six patients. Freedom from valve thrombosis was 78 and 70%, 10 and 15 years after surgery, respectively. The linearized rate of the valve thrombosis was 2.9%/patient-years. Six patients required reoperation. The mean interval to reoperation was 9.5 years. Freedom from reoperation was 83% and 75%, 10 and 15 years after surgery, respectively. The linearized rate of the reoperation was 2.8%/patient-years. No structural valve deterioration was found. Echocardiographic study showed that the function of the St. Jude Medical valve without valve-related complications was well maintained. CONCLUSIONS The higher thrombogenicity of the St. Jude Medical valve in the tricuspid position altered our choice of valve substitutes from the St. Jude Medical valve to a bioprosthesis which is lack of need for anticoagulant therapy except for juvenile patients who are able to maintain potent anticoagulant therapy.

Aortic root replacement with a composite graft: Results of 69 operations in 66 patients

Between December 1973 and December 1992, 66 patients underwent aortic root replacement at our hospital. The mean age of the patients was 42.5 years (range, 20 to 71 years); 44 patients were male and 22 were female. Of the 66 patients, 34 (51.5%) had clinical stigmata of Marfans syndrome. The aortic pathology requiring aortic root replacement was annuloaortic ectasia in 59 patients, aortic dissection in 5, and progressive dilatation of the ascending aorta after aortic valve replacement in 2. Twelve of the 59 patients with annuloaortic ectasia also had aortic dissection. The operative techniques used were the Bentall technique in 36 operations, the Cabrol technique in 21, the aortic button technique in 3, and other miscellaneous techniques in 9. The hospital mortality rate for the primary operation was 10.6% (7 patients), and the late mortality rate was 20.3% (12 patients). Four of the late deaths were related to the graft valve prosthesis, and 6 were related to the progression of aneurysmal diseases on the remaining aorta. The survival rate was 71.0% at 10 years. Pseudoaneurysm at the suture lines was detected in 7 patients, 6 of whom had been treated with the Bentall technique, and 5 patients also had Marfans syndrome. No patients having aortic root replacement with the Cabrol technique have required reoperation for pseudoaneurysms.(ABSTRACT TRUNCATED AT 250 WORDS)

Obstruction of mechanical valve prostheses: clinical diagnosis and surgical or nonsurgical treatment.

Twenty patients underwent nonsurgical and/or surgical treatment for obstruction of mechanical prosthetic valves. The obstructed prosthetic valve was in the aortic position in 11 patients, in the mitral position in 5, and in the tricuspid position in 4. Twelve patients had a bileaflet valve (3 aortic, 5 mitral, 4 tricuspid), and 8 had a tilting disk valve (all aortic). The diagnosis of prosthetic valve obstruction was made by cineradiography and echocardiography. Thrombolytic therapy was instituted in a series of our 10 most recent patients (11 cases), except for one patient with acute renal failure, regardless of the position of the obstructed prosthetic valve. Successful thrombolysis was achieved in 6 cases (54.5%). Six patients required surgical treatment subsequent to either failed or incomplete thrombolysis, and one patient died of congestive heart failure 1 month after surgery. Nonfatal neurologic events occurred in 2 cases (18.2%). A total of 16 patients underwent surgical treatment. Two (12.6%) of the 16 patients died of causes unrelated to the operative procedures before discharge from the hospital. These results suggest that thrombolytic therapy appears to be an attractive nonsurgical alternative for valve thrombosis when the patients clinical condition is not critical, and thus surgical treatment should only be performed in an emergency on seriously ill patients.

Partial brachiocephalic perfusion in aortic arch replacement

Eleven patients who underwent replacement of the aortic arch or adjacent areas for aneurysmal disease between 1989 and 1991, using hypothermic cardiopulmonary bypass at 20° to 23°C with partial brachiocephalic perfusion, were studied. Selective perfusion of the innominate artery was performed in all 11 patients through the right axillary artery, while partial brachiocephalic perfusion was carried out using a separate arterial roller pump with a perfusion flow rate of 10ml/kg per min. Direct cannulation to the left common carotid and left subclavian artery was not performed in this method. There were 4 men and 7 women who ranged in age from 26 to 78 years, with a mean age of 56 years. The etiology of aneurysmal disease was aortic dissection in 10 patients, and aortitis syndrome in 1. The cardiopulmonary bypass time was 214.3±39.3 min, aortic cross-clamp time 131.5±33.4 min, and partial brachiocephalic perfusion time 57.6±15.1 min. There were three operative deaths (27.3%), the causes being multiple organ failure, acute peritonitis, and infection of the composite graft in the ascending aorta, in one patient each, respectively. However, there were no deaths related to the technique of partial brachiocephalic perfusion and no neurological complications were seen in this series. Thus, we believe that partial brachiocephalic perfusion under hypothermic cardiopulmonary bypass is safe and effective in surgery for aortic aneurysms involving the aortic arch.Twenty patients with aneurysm or dissection of the aortic arch underwent surgical treatment using partial brachiocephalic perfusion (PBP). The right subclavian artery (SA) and common femoral artery were separately cannulated and perfused by individual pump heads. The flow to SA was 4.5-11 (9.9 +/- 1.4) ml/min/kg. The mean distal stump pressure of the left superficial temporal arteries before beginning the CPB were 36-64 (50.6 +/- 8.3) mmHg. The rectal temperature during PBP was maintained at 20.1-25.0 degrees C. The PBP time ranged 32 to 157 min. We studied the oxygen saturation of left internal jugular vein (SjO2) and cerebral circulatory index (CCI) during the PBP. SjO2 ranged from 72.9 to 99.4% and CCI were maintained at more than twice the CCI measured before beginning the CPB. We applied this simplified method (PBP) to the 20 patients with aortic aneurysms. No neurological complication were seen in these 19 patients without one patient. These clinical studies suggest that the PBP under hypothermic CPB is a safe and reliable method of cerebral protection for replacement of the aortic arch.

Long-term results of mitral valve repair for non-rheumatic mitral regurgitation.

The durability of mitral valve repaired with reconstructive techniques is variable. If the durability continues to be good, mitral valve repair may be the procedure of choice in many patients with mitral regurgitation. Between December 1970 and June 1993, 54 patients had mitral valve repair for non-rheumatic mitral regurgitation. There were 38 men and 16 women with a mean age of 46.8 (range 19-68) years. The pathology which required surgical treatment was torn chordae in 38 patients, elongation of the chordae in five, valve prolapse without elongation or rupture of the chordae in six, infective endocarditis in three, and annular dilatation in two. Forty-four patients had triangular or quadrangular resection of the mitral leaflet, and seven had annuloplasty alone. Choral reconstruction was performed on three patients. There were no operative deaths. Five patients (9%) died late after operation. The actuarial survival rate and the valve-related death-free rate at 10 years were 83.9% and 90.0%, respectively. Seven patients (13%) required reoperation. Freedom from reoperation at 10 years was 84.5%. Improper evaluation of residual regurgitation during operation and suture dehiscence were the principal causes of reoperation. It was concluded that mitral valve repair for non-rheumatic mitral regurgitation showed low operative mortality and stable long-term results. It is suggested that intraoperative transoesophageal colour Doppler echocardiography provides accurate assessment of mitral valve competence and may be helpful in reducing the need for reoperation.

Concentric wear of the Delrin disc in a Bjork-Shiley heart valve prosthesis: report of two cases.

We report herein the cases of two patients who received replacement of aortic Bjork-Shiley Delrin (BSD) valves that had been implanted for over 20 years following the development of aortic regurgitation (AR) resulting from wear of a Delrin disc. Case 1 was a 61-year-old woman in whom echocardiography revealed marked left ventricular dilatation and moderate AR 23 years after an aortic valve replacement (AVR) with a 21-mm BSD valve. Case 2 was a 51-year-old woman in whom echocardiography revealed marked dilation of the right atrium and moderate AR 23 years and 8 months after an AVR with a 21-mm BSD valve, as well as a mitral valve replacement with a 3M Starr-Edwards (SE) ball valve and tricuspid annuloplasty. In both patients, the BSD valves were replaced with other mechanical valves at reoperation. Examination of the explanted BSD valves showed that the Delrin discs contained increases in the radial gaps and strut indentation grooves on the inflow and outflow surfaces. The type and magnitude of the wear on the Delrin discs in these valves were consistent with data reported in the literature for this valve design after similar implant duration.

Reconstruction of the Mitral Annulus With Porcine Pericardium

A 60-year-old man was admitted to our hospital for investigation of dyspnea and disorientation with right hemiplegia. Echocardiography showed thickened mitral valve leaflets with vegetations and severe mitral regurgitation. Blood cultures grew Staphylococcus aureus. During the operation, perforation and destruction of the mitral valve leaflets and vegetations were confirmed. Debridement of the infected tissues resulted in segmental disruption of the posterior mitral fibrous annulus. Reconstruction of the mitral annulus with porcine pericardium treated with glutaraldehyde and mitral valve replacement were successful. The patients postoperative course was complicated with metastatic cerebral and splenic abscesses. After splenectomy on the 8th postoperative day, he gradually recovered without major neurologic sequelae. We believe that reconstruction of the mitral valve annulus with pericardium, especially autologous pericardium, is reliable and useful for the treatment of patients with disruption of the mitral valve annulus.

Reoperations for Aneurysmal Disease of the Ascending Aorta, Aortic Arch, and Descending Aorta: Their Causes and Operative Results

Between 1984 and 1993, 20 patients underwent reoperation for the thoracic aorta or ascending aorta and aortic valve. There were 14 male and 6 female patients who ranged in age from 28 to 70 years with a mean of 53.2 years. The mean interval between initial operation and the 2nd operation was 70.4 months. Of the 20 patients, 6 had stigmata of Marfans syndrome. The primary aortic pathology requiring initial operation was annuloaortic ectasia in 10 patients, aortic valvular disease in 5, aortic dissection in 3, and mega aorta syndrome, aortic aneurysm in multiple segments, or aortic arch aneurysm in 1 each. Cause of reoperation was pseudoaneurysm formation at suture lines in the ascending aorta in 6 patients, new or progressive dilatation in the remaining aortic segment in 5, new or persistent aortic dissection in 4, graft infection in 2, and recurrent aortic arch aneurysm in 1. The remaining 2 patients received a planned two-stage operation for multiple aneurysms or mega aorta syndrome. Six patients died early after reoperation, yielding a hospital mortality rate of 30%; however, 3 of the 6 deaths were related to a compromised preoperative clinical condition and 1 to perioperative contamination. Two operative deaths (10%) were related to operative techniques. Results suggest application of separate grafts for coronary artery reattachment, as in the Cabrol or Piehler techniques, or the aortic button technique for aortic root replacement, may help eliminate pseudoaneurysm formation, which is one of the major complications after operations on the ascending aorta. It is also suggested that early diagnosis and prompt operative treatment for recurrent or residual aneurysmal diseases of the aorta may be essential for successful definitive treatment.

Surgical treatment for acute aortic dissection and coexistent degenerative aortic aneurysm. Report of three cases.

Acute aortic dissection occurring in an aorta previously afflicted with degenerative, atherosclerotic is unusual. We report three cases with acute aortic dissection (DeBakey type III-b) occurring in an aorta which had a preexistent degenerative aortic aneurysm. Two of the three patients had acute aortic dissection originating from the distal end of the degenerative aneurysm, and the remaining one had the acute aortic dissection and degenerative aneurysm at different segments of the aorta. Since the risk of rupture is likely to be much higher in the patients with coexistence of acute aortic dissection and degenerative aortic aneurysm, compared with patients with DeBakey type III acute aortic dissection alone, we believe that a prompt and aggressive surgical approach is essential to prevent rupture, and that digital subtraction angiography (DSA) is more helpful in making a correct diagnosis and in helping to decide surgical procedures and supportive methods than other noninvasive diagnostic procedures.