Search

Background: Steroid use during cardiac operations may reduce the risk of postperfusion lung syndrome, but both cardiopulmonary bypass and steroids are immunosuppressive. The synergistic effects of the bypass and steroids on patients' immunologic activities, hemodynamics, and metabolisms during and after heart operations have not been clarified systematically., Methods: Twenty-four patients undergoing valve replacement were studied in a randomized, double-blind trial. Twelve of these patients (S group) received bolus methylprednisolone, 20 mg/kg body weight, and the remaining 12 patients (C group) received a placebo intravenously before and after bypass. Blood cell count, C-reactive protein, lymphocyte surface markers (CD3, CD4, CD8, CD16, and CD20), phytohemagglutinin response, interleukin-2 production, and natural killer cell activity were examined on admission through day 7. Cardiac output, blood gas, electrolyte, lactate, and serum glucose levels were examined perioperatively., Results: The peak white blood cell count in the S group was higher than that in the C group (analysis of variance: p [group] = 0.0436). The peak C-reactive protein level was higher in the C group than in the S group (p [group] < 0.0001). From the analysis of the surface markers, the steroid increased the natural killer cells before and soon after bypass (p [group] = 0.0117), and later tended to increase the CD4+ T and B cells during the postoperative recovery period. The phytohemagglutinin response in both groups decreased after bypass (p [time] < 0.0001), but the steroid caused exaggerated decreases before (p < 0.01 by Student's t test) and soon after (p < 0.001) bypass in the S group (analysis of variance: p [group] = 0.0127). The interleukin-2 production was suppressed by bypass alone after the bypass in the C group, but was further suppressed by the steroid before and after bypass in the S group (p [group] = 0.0446). The cardiac index, water balance, electrolytes, arterial oxygen tension, and timing of extubation were not different between the groups. In contrast, the glucose (p [group] = 0.0486) and lactate (p [group] = 0.0525) levels were higher in the S group than those in the C group., Conclusions: T-cell functions are synergistically suppressed by cardiopulmonary bypass and high-dose methylprednisolone in heart operations. The hemodynamic benefits of the steroid are negligible, whereas glucose tolerance is worsened by the steroid during bypass.

A simplified Manouguian's aortic annular enlargement for aortic valve replacement with prosthetic valve was performed in a patient with severe aortic stenosis and mild regurgitation by preserving both the anterior mitral leaflet and the left atrial roof intact. This method minimized the operative risk by avoiding injury to the mitral valve, while inserting a possibly two-size-larger prosthetic valve. The inserted prosthetic valve was positioned parallel to the original aortic valve. Moreover, the incision from the top of the commissure between the noncoronary cusp and left coronary cusp through the interventricular fibrous trigone appears to be easily extended into the exact center of the anterior mitral leaflet if further enlargement is required.

A retrospective study was conducted on 124 patients who underwent re-replacement of previously implanted prosthetic heart valves for structural valve failure, prosthetic valve endocarditis, periprosthetic leak, a thrombosed valve, hemolysis, or prophylactic removal. In total, 85% of the explanted valves were bioprostheses, and 70% of the newly implanted valves were mechanical valves. The overall operative mortality rate was 8.1%, being 3.2% of 95 single valve recipients and 25.0% of 28 double valve recipients (P < 0.001). The overall mortality rate dropped from 13.6% of 66 patients before 1988, to 1.7% of 58 patients encountered in the last 3 years (P < 0.02). Since 1988, a third of the patients have undergone reoperation without homologous blood transfusion. A univariate analysis revealed eight operative risk factors, namely: higher values of preoperative blood urea nitrogen or total bilirubin, double valve replacement at the redo operation, NYHA class IV, urgency of reoperation, a duration of implantation of less than 3 months, reoperation in the earlier period of this study, and reexploration for bleeding or cardiac tamponade after re-replacement surgery. A multivariate statistical analysis demonstrated that preoperative blood urea nitrogen, urgency of reoperation, double valve replacement, and the duration of implantation were independent risk factors. Thus, we recommend that surgery be performed early, before the occurrence of other organ failure induced by congestive heart failure due to any form of valve dysfunction.

A case of active prosthetic valve infective endocarditis (PVE) due to Candida glabrata was successfully treated by the systemic administration of fluconazole. A 66-year-old Japanese man with infective endocarditis of unknown etiology underwent aortic and mitral valve replacement to treat severe aortic and mitral regurgitation associated with multiple organ failure. Postsurgical cultures of arterial blood were repeatedly positive for C. glabrata, and therefore fluconazole was administered either intravenously or orally at a dose of 400 mg/day for 46 days. During that time the signs of inflammation including fever such as an elevated white blood cell count and the presence of C-reactive protein (CRP) all improved while the blood cultures became negative. Fluconazole is thus considered to be effective in treating PVE caused by C. glabrata. When administering this treatment, it is also important to monitor the patient's renal and liver function.

The mitral apparatus can affect left ventricular function through various mechanisms, such as the direct mechanical coupling between the mitral anulus and papillary muscle and the mitral annular contraction. To evaluate the relative contribution of these mechanisms, we investigated in five groups of 35 dogs that underwent open chest operations how preservation of the mitral apparatus affects left ventricular systolic function. We performed atriotomy in the first group. We sutured a prosthetic rigid ring around the mitral anulus in the second group. We replaced the mitral valve and preserved the anterior chordae in the third group, the posterior chordae in the fourth group, and no chordae in the fifth group. The postoperative percentage of recovery of ventricular function (as assessed by the slope of the end-systolic pressure-volume relation) from preoperative control values were 92.2% +/- 4.8%, 89.5% +/- 12.8%, 85.7% +/- 9.5%, 75.1% +/- 12.9%, and 61.3% +/- 8.0%, respectively. Preservation of the mitral apparatus significantly improved left ventricular function compared with that of conventional mitral valve replacement. The average relative contribution of the ventricular muscle to left ventricular function, the mitral anulus-papillary muscle continuity, and the mitral annular contraction were 66.5%, 30.6%, and 2.9%, respectively. We conclude that it is more beneficial to preserve the mitral apparatus in mitral valve replacement. The prosthetic ring does not detract from the functional benefit of the preservation of the mitral apparatus.

From February 1975 to August 1981, 23 consecutive patients underwent tricuspid valve replacement, which was either isolated (six patients) or combined with the replacement of other valves (17) by means of a standard, glutaraldehyde-preserved Hancock porcine bioprostheses. Patients' ages ranged from 9 to 53 (mean 36.2) years. The follow-up period ranged from 0.2 to 16.5 years (mean 9.1) and was complete in 100% of all cases. Structural valve failure of the tricuspid Hancock valve was noticed in two patients, a 9-year-old boy and a 13-year-old girl 3.4 and 16.5 years after implantation, respectively. The actuarial freedom rate from structural valve failure at 10 years was 94 +/- 6%. There were six tricuspid prosthesis-related events: structural valve failure in two and valve thrombosis, anticoagulant-related bleeding, prosthetic valve endocarditis, and periprosthetic leak in one each, respectively. The actuarial freedom from these events at 10 years was 78 +/- 10%. Five pairs of aortic/mitral-tricuspid Hancock valves were explanted simultaneously from the same patients after 8.1 to 13.9 (mean 11.4) years postoperatively. A gross examination showed no valve dysfunction in the explants from the tricuspid position, but degenerative changes with valve dysfunction in those from the mitral and aortic position were observed (none of five versus five of seven; p < 0.03). We concluded that the selection of a Hancock bioprosthesis in the tricuspid position is acceptable because of the low incidence of prosthesis-related complications and the excellent durability of more than 10 years.

Although Manouguian's operation is well established, there have been little long-term data published on its outcome. From January 1980 to June 1988, 15 patients underwent patch enlargement of the small aortic anulus by Manouguian's approach, either with aortic single valve replacement (7 patients) or with aortic-mitral double valve replacement (8 patients). Follow-up ranged from 3.0 to 11.4 years (mean 8.5) and was completed with a cumulative total of 102 patient-years. One patient died of fulminant hemolysis, probably related to turbulent jet flow and Dacron patch material (operative mortality 6.7%). There were four late deaths, and the actuarial survival, including operative death at 10 years, was 62% +/- 14%. Reoperations were performed seven times in six patients. Most of these complications were not considered to be caused by the anulus-enlarging procedure. Actuarial freedom rate from reoperation at 10 years was 65% +/- 15%. Four patients underwent rereplacement of prostheses for Hancock valve failure during 2.9 to 11.3 years (mean 8.2 years). The anulus enlargement was found to be well healed and presented no problem during reoperation. Surgically induced mitral regurgitation by Manouguian's procedure was observed in two patients. The regurgitation did not progress during follow-up duration of 1.9 to 10.0 years, nor did it cause congestive heart failure. Annular enlargement by Manouguian's procedure with use of mechanical valves is one of the good selections in patients with the narrow aortic valve ring.

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.

From 1974 to March 1991, 34 patients were operated on for ascending aortic aneurysm with aortic regurgitation caused by annuloaortic ectasia (18), dissecting aneurysm (11) and so on. Twenty-one patients underwent composite valve graft replacement, 7 separate valve graft replacement, 5 aortic resuspension and graft replacement, and one aortorrhaphy and aortic valve replacement. Four of these patients required ascending aorta and arch reconstruction. Another two patients who had previous separate valve graft replacement for annulaortic ectasia and required reoperation underwent Bentall operation successfully. The 30-day survival rate was 94%. Recently, we adopted open-unwrapping and aortic button technique. As a result we achieved no homologous blood transfusion by using "Cell Saver" and autologous blood preoperative storage program in four out of five patients of Bentall operation. Late survival rate including operative death were 78% and 63% at 5 and 10 years after operation, respectively.

Comparative long-term performance characteristics of St. Jude Medical (SJM) and bioprosthetic valves were conducted retrospectively for patients who underwent prosthetic valve replacement in the right side of the heart from 1975 to 1988. Fifty-four patients received either SJM (n = 18) or bioprosthetic (n = 37) valves. The cumulative follow-up for SJM valves was 91 valves-years (range 3.9 to 7.2 years) and that for bioprostheses was 282 valve-years (range 1.3 to 14.8 years). Follow-up rate was 100%. The actuarial survival rate excluding hospital deaths at 5 years was 81 +/- 10% for SJM and 97 +/- 3% for bioprosthetic valve recipients (p = ns). The rates of freedom from thrombosis or anticoagulant-related hemorrhage, structural valve failure, prosthetic valve endocarditis, reoperation, and overall valve-related complications at 5 years were 72 +/- 11%, 100%, 100%, 83 +/- 9%, and 72 +/- 11% for SJM valve recipients, and 100%, 97 +/- 3%, 97 +/- 3%, 94 +/- 4%, and 94 +/- 4% for bioprosthetic valve recipients, respectively. Structural valve failure, prosthetic valve endocarditis and reoperations occurred at a similar incidence in each of the two types of prostheses. Thrombosis and overall valve-related events occurred more frequently in SJM valve recipients (5.5 +/- 2.5 vs 0%/valve-year; p less than 0.02, 6.6 +/- 2.7 vs 1.1 +/- 0.6 %/valve-year; p less than 0.03, respectively). The bioprosthetic valve which did not need warfarin anticoagulation therapy had low incidence of valve-related complications and showed good long-term durability even in the younger age group. The bioprosthetic valve was superior to the SJM valve in the right side of the heart.

From May 1975 through December 1988, 91 patients (mean age 50.4 +/- 12.8 years) had first-time surgery for mitral pure regurgitation; 48 had mitral valve replacement (MVR) and 43 had valve repair. A majority of the patients had non-rheumatic valvular diseases. Those patients who underwent repair had less hemodynamic and functional derangement than those who underwent MVR. The operative mortality was 8.3% in the MVR group and 2.3% in the repair group. Seventeen percent of the MVR group and 2% of the repair group required intra-aortic balloon pumping support (p less than 0.03). A higher dose of dopamine and/or dobutamine during the early postoperative period was necessary in the MVR group (7.0 +/- 4.8 micrograms/kg/min) than in the repair group (5.1 +/- 3.1 micrograms/kg/min). Duration of respirator support for hospital survivors was longer in the MVR group (2.3 +/- 2.7 days) than in the repair group (1.4 +/- 1.0 days). There were 5 late deaths (2.2 +/- 1.0%/pt-yr) not counting 6 non-cardiac deaths in the MVR group and 1 (0.6 +/- 0.6%/pt-yr) in the repair group. There were 17 patients (7.5 +/- 1.8%/pt-yr) who experienced treatment failure in the MVR group and 5 (2.3 +/- 1.3%/pt-yr) in the repair group (p less than 0.02). Eight patients in the MVR group (3.5 +/- 1.3%/pt-yr) underwent repeat surgery in the late postoperative period, as did 3 (1.7 +/- 1.0%/pt-yr) in the repair group. There was no increase in the incidence of repeat surgery after valve repair. All the current survivors in the repair group, and 96% of those in the MVR group were in NYHA functional class I or II. These results indicate that mitral repair is the preferred operative procedure for pure mitral regurgitation, whenever it is possible.

From May 1975 to December 1988, 62 patients underwent 66 replacements of prosthetic heart valves, due to structural valve failure in 37, prosthetic valve endocarditis (PVE) in 17, periprosthetic leak in 5, thrombosed valve in 3, hemolysis in 2, and prophylactic removal in 2. Before reoperation, 3 patients were in NYHA Class I, 24 in Class II, 21 in Class III, and 18 in Class IV. Replacements of valve prostheses were at the mitral position in 33 patients, at the aortic position in 16, at the aortic and mitral position in 9, at the mitral and tricuspid position in 5, at the tricuspid position in 2, and at the pulmonary position in 1. There were 6 early deaths (9.1%), and 13 late deaths (7.2 +/- 0.4%/patient-year). Clinical improvement of the current survivors was good. The follow-up duration was 4 months to 11.4 years (mean 3.5 years), and the cumulative follow-up was 180 patient-years (100% complete). Patients undergoing replacement of 2 prostheses showed a higher early mortality rate (35.7%) than those who received replacement of 1 prosthesis (1.9%) (p less than 0.01). The actuarial survival including early deaths was compared using the generalized Wilcoxon test. Survival was better in patients with replacement of one prosthesis than in those with replacement of 2 prostheses (p less than 0.001), and was better in NYHA Class I to III patients than in Class IV patients (p less than 0.05). Replacement of 1 prosthesis for patients with primary tissue failure of bioprostheses showed no operative mortality and a good 5 year survival rate (96 +/- 4%). High risk factors for replacement of prosthetic valves included double valve replacement, NYHA Class IV and PVE.

Comparative long-term performance characteristics of mechanical valves and bioprosthetic valves were analyzed retrospectively for patients who had undergone isolated mitral valve replacement from 1967 to 1988. Two hundred ninety-one patients received either mechanical (n = 97) or bioprosthetic (n = 194) valves. The cumulative follow-up was 1,609 patient-years (mean 6.3 +/- 3.8 years, ranging from 0.6 to 20.2 years, 98.9% complete follow-up). The actuarial survival rate, including hospital deaths, at 10 years was 72 +/- 12% for mechanical and 74 +/- 4% for bioprosthetic valve recipients. The rates of freedom from thromboembolism, structural valve failure, prosthetic valve endocarditis, prosthetic valve endocarditis, reoperation, and overall valve-related complications at 10 years were 87 +/- 5%, 100%, 91 +/- 3%, 100%, and 79 +/- 8% for mechanical valve recipients and 85 +/- 3%, 77 +/- 5% (p less than 0.001), 85 +/- 13%, 71 +/- 5% (p less than 0.001), and 52 +/- 5% (p less than 0.001) for bioprosthetic valve recipients, respectively. Thromboembolism occurred at a similar incidence in two types of valves (2.0 +/- 0.7 vs. 2.2 +/- 0.4%/pt-yr). Structural valve failure, reoperations, and overall valve-related events occurred more frequently in the bioprostheses recipients (0 vs. 2.0 +/- 0.4%/pt-yr; p less than 0.001, 0.3 +/- 0.3 vs. 2.9 +/- 0.5%/pt-yr; p less than 0.001, 2.5 +/- 0.8 vs. 5.6 +/- 0.7%/pt-yr; p less than 0.005, respectively). There was no mortality at the time of redo-operation. These results show that bioprostheses in the mitral position exhibit small benefits of antithrombogenesis and prominent disadvantage of poor durability requiring reoperation.

Comparative long-term performance characteristics of mechanical valves and bioprosthetic valves were analyzed retrospectively among patients who had undergone isolated aortic valve replacement between 1968 and 1987. One hundred sixty-seven patients received either mechanical (n = 82) or bioprosthetic (n = 85) valves. The cumulative follow-up was 926 patient-years (mean 6.1 +/- 4.7 years, ranging from 0.5 to 20.2 years, 100% complete follow-up). Actuarial survival rate, including operative death, at 10 years was 74 +/- 7% for mechanical and 77 +/- 7% for bioprosthetic valve recipients. The rates of freedom from thromboembolism, structural valve failure, prosthetic valve endocarditis, and valve re-replacement at 10 years were 77 +/- 7%, 100%, 96 +/- 2% and 95 +/- 3% for mechanical, and 94 +/- 4%, 83 +/- 8% (p less than 0.05), 88 +/- 5% and 75 +/- 8% (p less than 0.05) for bioprosthetic valve recipients, respectively. Thromboembolism occurred more frequently in the mechanical valve recipients (p less than 0.01), and structural valve failure in the bioprostheses recipients (p less than 0.05). There was no mortality at the time of valve re-replacement. Most of the bioprosthesis recipients received no anticoagulation therapy beyond 3 months postoperatively. Cardiac medication in the late postoperative period was not required in 31.3% of bioprosthetic, and 3.2% of mechanical valve recipients (p less than 0.01). These results show that bioprosthesis in the aortic position exhibits a superb antithrombogenicity and may enable a drug-free state, though its limited durability requires reoperation.

Using a method of our own design, we evaluated intraoperatively the function of prosthetic heart valves. The changing hemodynamics induced by a stress test were assessed by simultaneously measuring the mean transvalvular pressure gradient and the stroke volume. The effective orifice area (EOA) of the valves was determined for each stroke by computer analysis, and this value was compared with the actual orifice area. Data were collected from 19 patients undergoing aortic or mitral valve replacement or both with 17 St. Jude Medical and 12 Ionescu-Shiley valves. The mean pressure gradient increased with tachycardia and an increase in mean left atrial pressure in the mitral position, but decreased with a decrease in cardiac output and peak left ventricular pressure in the aortic position. The St. Jude Medical valve had a smaller mean pressure gradient than the Ionescu-Shiley bioprosthesis. For both valves, the EOA increased with valve size. The St. Jude Medical valve had a greater EOA than the Ionescu-Shiley bioprosthesis, regardless of the valve size (p less than 0.005). However, the performance of prosthetic leaflets was better with the Ionescu-Shiley bioprosthesis than with the St. Jude Medical mechanical valve (p less than 0.001). This method involving computer analysis of each cardiac cycle proved to be useful for evaluating prosthetic heart valve function in the presence of changing hemodynamics.

Clinical results with mechanical and bioprosthetic valve replacements for tricuspid and/or pulmonary positions were reviewed. Between February 1975 and December 1985, 34 bioprostheses (B) (22 Hancock, 9 Ionescu-Shiley and 3 Carpentier-Edwards pericardial) and 18 mechanical prostheses (M) (St. Jude Medical) were implanted in our institute excluding hospital death. Group with B included 29 tricuspid valve replacements and 5 pulmonary valve replacements. Group with M included 9 tricuspid valve replacements, 7 pulmonary valve replacements and 1 both valve replacements. The cumulative follow-up period was 207.2 patient-years (p-t) in group B and 55.0 p-y in group M. The incidence of valve failure was 0.48 +/- 0.48% per p-y in group B and 7.27 +/- 3.64% per p-y in group M (p less than 0.001). The incidence of valve-related events was 1.93 +/- 0.97% per p-y in group B and 9.09 +/- 4.07% per p-y in group M (p less than 0.001). At 3 years, the percent free of valve failure was 100 +/- 0% in group B and 76.8 +/- 10.2% in group M (p less than 0.05). Fourteen bioprosthetic valves (B') and 10 mechanical valves (M') were implanted at the right-sided cardiac valve position alone. The cumulative follow-up period was 94.2 p-y in group B' and 32.3 p-y in group M'. The incidence of valve-related events was 1.06 +/- 1.06% per p-y in group B' and 12.4 +/- 6.19% per p-y in group M' (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Twenty patients with active infective endocarditis, 11 with native valve endocarditis (NVE) and 9 with prosthetic valve endocarditis (PVE), were treated surgically from 1975 through April 1987 at Kyushu University Hospital. The operative indications were congestive heart failure mainly due to massive aortic regurgitation in 18, periannular abscess in 6, major embolism in 5 and severe hemolysis in 3 patients. In the group of NVE, single aortic valve replacement was performed in 4 patients and multiple valve replacement in the remainder. One patient died early postoperatively from LOS. Two patients with recurrent infective endocarditis, which occurred within 60 days after previous prosthetic valve replacement, were operated subsequently as early PVE. All other patients became NYHA class I postoperatively except for one patient who died from thrombosed valve. In the group PVE, re-AVR was done in 3, re-MVR in five, double valve replacement in two and re-fixation of the prosthesis to the aortic annulus in one patient. Two patients with early PVE died from recurrent endocarditis late postoperatively. One of 7 patients with late PVE, who had suffered from myocardial and cerebral infarction before reoperation, died from multiple organ failure. There were 3 patients with perivalvular leakage due to late active PVE, whose preoperative signs of inflammation were negative or minimum. As recurrent perivalvular leakage due to persistent infective endocarditis might frequently occur in such cases, complete resection and debridement of infected foci should be emphasized.

Bentall's operation using a composite graft for complete replacement of an ascending aortic aneurysm and associated incompetent aortic valve is being widely used. In case of no displacement of the coronary origins, however, this technique often leads to difficulties in restoring the coronary flow. We now report a successful modification for this coronary-graft anastomosis.