Should a bicuspid aortic valve be replaced in the presence of subvalvar or supravalvar aortic stenosis?

BACKGROUND: A bicuspid aortic valve is commonly associated with other levels of left ventricular outflow tract obstruction. Providing the bicuspid aortic valve is competent and nonobstructive, repair of subvalvar or supravalvar stenosis usually focuses on the obstructive lesions, leaving the valve in situ. The aim of this report was to examine the impact of a bicuspid aortic valve on the risk of reoperation for patients undergoing operation for subvalvar or supravalvar aortic stenosis. METHODS: Since 1976, 47 patients with supravalvar or subvalvar aortic stenosis have undergone repair. The median follow-up is 5.1 years (range, 2 months to 20.1 years). Sixteen patients (34%) had a bicuspid aortic valve that was competent and nonobstructive, and 31 (66%) had a tricuspid aortic valve. RESULTS: Reoperation was required in 9 patients (56%) with a bicuspid aortic valve, in each involving aortic valve replacement with an autograft (3), homograft (2), or prosthesis (4). Six patients (19%) with a tricuspid aortic valve required reoperation, yet only 1 required aortic valve replacement. The freedom from valve replacement was 43% (70% confidence interval, 31% to 55%) in the bicuspid aortic valve group versus 100% (70% confidence interval, 94% to 99.5%) in the tricuspid group at 5 years (p = 0.0001). The freedom from any reoperation at 5 years was 43% (70% confidence interval, 31% to 55%) in patients with a bicuspid aortic valve versus 86% (70% confidence interval, 80% to 93%) in the tricuspid group (p = 0.02). CONCLUSIONS: The data suggest that patients with subvalvar or supravalvar aortic stenosis and a bicuspid valve may be better palliated with a more definitive operation such as the Ross or Ross-Konno procedure.     

Aortic valve replacement with cryopreserved aortic allograft: ten-year experience

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.     

Valve repair in infective endocarditis

From 1985 to 1995, 12 patients with native valve endocarditis underwent valve repair instead of replacement. Mean age was 41.9 years (range from 5 to 79 years). Eight patients had active and 4 patients inactive infection. The mitral valve was involved in 6 patients, the aortic valve in 1, both valves in 2, the tricuspid valve in 2, and the mitral and pulmonary valves in 1. The pathological findings were as follows: leaflet perforation in 2 patients, chordal rupture in 3, and vegetations in 10. Valve sparing procedures were carried out on the mitral valve in 8 patients, on the aortic valve in 1, on the tricuspid valve in 2, and on the pulmonary valve in 1. The following repair techniques were used: vegetectomy in 10 patients, leaflet patching in 2, posterior mitral leaflet resection in 3, mitral annuloplasty in 4, and pulmonary valve repair in 1. Uncontrolled sepsis, progressive heart failure, peripheral embolism, and echocardiographically demonstrated vegetations were the indications for surgery. There was no operative or late mortality and all infections were cured with no recurrences. One patient required valve replacement following aortic valve repair because of progressive aortic regurgitation. Postoperative Doppler echocardiography showed trivial to no regurgitation in 11 patients after valve repair. The overall outcome was favorable during the mean follow-up period of 39.3 months (range from 1 to 120 months). Reparative or reconstructive approaches for native valve endocarditis should be considered and can be successfully performed. Their advantages include (1) improved hemodynamics, (2) no recurrence, (3) no mortality, and (4) favorable long-term results.     

Impact of size mismatch and left ventricular function on performance of the St. Jude disc valve after aortic valve replacement

BACKGROUND: The hemodynamic function of the St. Jude valve may change relative to changes in left ventricular function after aortic valve replacement for aortic stenosis. From theoretical reasons one may hypothesize that prosthetic valve hemodynamic function is related to left ventricular failure and mismatch between valve size and patient/ventricular chamber size. METHODS: Forty patients aged 24 to 82 years who survived aortic valve replacement for aortic stenosis with a standard St. Jude disc valve (mean size, 23.5 mm; range, 19 to 29 mm) were followed up prospectively with Doppler echocardiography and radionuclide left ventriculography preoperatively and 9 days, 3 months, and 18 months after the operation with assessment of intravascular hemolysis at 18 months. Follow-up to a maximum of 7.4 years (mean, 6.3 years) was 100% complete. RESULTS: Left ventricular muscle mass index decreased from 198 +/- 62 g.m-2 preoperatively to 153 +/- 53 g.m-2 at 18 months (p < 0.001), paralleled by a significant increase in left ventricular ejection fraction, peak ejection rate, and peak filling rate; only 18% of the patients had normal left ventricular muscle mass index and only 32% normal ventricular function (normal left ventricular ejection fraction, peak ejection rate, peak filling rate, early filling fraction, and late filling fraction during atrial contraction) at 18 months. Prosthetic valve peak Doppler gradient dropped from 20 +/- 6 mm Hg at 9 days to 17 +/- 5 mm Hg at 18 months (p < 0.05). Reduction of left ventricular muscle mass index was unrelated to peak gradient and size of the valve. Peak gradient at 18 months rose with valve orifice diameter of 17 mm or less (by 6 mm Hg), orifice diameter/body surface area of 9 mm.m-2 or less (by 5 mm Hg), left ventricular enddiastolic dimension (by 23 mm Hg per 10 mm increase), and impaired ventricular function (by 3 mm Hg). All but 2 patients (5%) had intravascular hemolysis; none had anemia. Two patients with moderate paravalvular leak had the highest serum lactic dehydrogenase levels; 4 patients with trivial leak had higher serum lactic dehydrogenase levels than those without leak. Serum lactic dehydrogenase levels rose with moderate paravalvular leak, impaired ventricular function, and valve orifice diameter. Six patients with trivial or moderate paravalvular leak had a cumulative 7-year freedom from bleeding and thromboembolism of 44% +/- 22% compared with 87% +/- 5% for those without leak (p < 0.05). CONCLUSIONS: The peak gradient of the St. Jude aortic valve dropped marginally over the first 18 postoperative months in association with incomplete left ventricular hypertrophy regression and marginal improvement of ventricular function. Mismatch between valve size and ventricular cavity size or patient size and impaired function of a dilated ventricle significantly compromised the performance of the St. Jude valve. Probably explained by platelet destruction or activation, paravalvular leak was related to bleeding and thromboembolic complications.     

Usefulness of percutaneous cardiopulmonary bypass support in patients with difficulties in weaning from cardiopulmonary bypass

A percutaneous cardiopulmonary support system (PCPS) was used in 12 patients (mean age 68 years) between March 1991 and June 1996 for difficulties weaning from ordinary cardiopulmonary bypass. Cardiac procedures preceding the placement of the PCPS were coronary artery bypass grafting in 8 patients, aortic valve replacement in 1, double valve replacement in 1, and ascending aortic replacement for acute aortic dissection in 1. These procedures were elective in 6 patients and emergent in 6. Intraaortic balloon pumps were used in all cases except in two cases with atherosclerotic occlusive disease. Nine (75%) of the patients were weaned from PCPS, and seven (58%) were discharged. There were no complications due to the placement of PCPS except for three episodes of lower leg ischemia. We conclude that PCPS is useful in addressing difficulties in weaning from ordinary cardiopulmonary bypass and there should be further discussion about the limitations of PCPS in cases of severe circulatory failure.     

Sub-trochanteric fractures. A comparative study between gamma nail and angular osteosynthesis with lateral cortical support]

METHODS: Thirty-three children and young adults with congenital aortic valve disease underwent pulmonary autograft replacement of the aortic valve between October 1993 and March 1997. There wer six females and 27 males; at operation, median age was 16 years (range: 3 to 41 years) and median body weight 60 kg (range: 14 to 121 kg). Fifteen patients (46%) had undergone one or more previous cardiac surgical procedures. A bicuspid aortic valve was present in 31 patients (94%); moderate to severe aortic stenosis and regurgitation was present in 10 (30%) and 26 (79%), respectively. RESULTS: All patients underwent the Ross procedure while in NYHA class I (64%) or class II (36%). A preoperative shortening fraction of 41 +/- 1.4% suggested well-preserved systolic function, but the mean left ventricular end-diastolic pressure of 16.6 +/- 1.3 mmHg was consistent with preoperative left ventricular pressure and volume overload. The aortic root was replaced using an interrupted suture technique in two patients and with three separate running sutures in 31. The right ventricular outflow tract was reconstructed in all classes with a cryopreserved pulmonary homograft valved conduit (median diameter 23 mm; range 19 to 30 mm). Intraoperative complications included transient atrioventricular dissociation (one), permanent atrioventricular dissociation (one), and left coronary artery distortion relieved by shortening the distal ascending aorta (one). Postoperatively, postpericardiotomy syndrome developed in six patients (18%), supraventricular tachycardia in three (9%), and ventricular tachycardia in one (3%). At three days after surgery, one patient developed ischemic left ventricular dysfunction requiring repositioning of the distorted left coronary artery higher on the neo-aortic root. Hospital survival rate was 100%. During a median follow-up of 17 months (range: 1 to 41 months) one patient suffered a non-cardiac death due to blunt trauma. there has been a significant postoperative improvement in NYHA class among surviving patients (class I, 94%; class II, 6%; p = 0.004 versus preoperative). Postoperative aortic regurgitation was absent or trivial in 17 (60%) and mild in the remaining 11 (40%) patients for whom follow-up echocardiographic data are available. One patient required reoperation 16.5 months after the Ross procedure to replace a rapidly degenerating pulmonary homograft, and one with moderately severe homograft stenosis and five with mild homograft stenosis are being monitored. Postoperatively, a gradual early expansion in the diameter of the neo-aortic root and reduction in echocardiographic indices of left ventricular hypertrophy and dilatation occurred. CONCLUSIONS: Pulmonary autograft replacement of the aortic valve in young patients with congenital aortic valve disease has produced excellent short-term anatomic/physiologic results and symptomatic relief with no mortality. Indices of left ventricular dilatation and hypertrophy regress after repair when the Ross operation precedes important deterioration in preoperative ventricular function. Important technical considerations include: (i) the native distal ascending aorta should be sufficiently shortened before performing the distal aortic anastomosis; and (ii) the left coronary anastomosis should be positioned relatively high on the neo-aortic root with a slight amount of tension. Both of these maneuvers reduce the likelihood of coronary artery distortion. Rapid degeneration of the pulmonary homograft and the propensity towards progressive dilatation of the neo-aorta are important postoperative considerations. Until more is known about the etiology and natural history of these two potential complications, postoperative anti-inflammatory and/or immunosuppressive therapy and strict control of hypertension should be strongly considered.     

Aortic valve replacement with biological substitute

In the quest for an ideal aortic valve substitute, homografts and autografts are well-established options. We reviewed our results with homografts and autografts for aortic valve replacement during the last 5 years. From March 1992 through July 1997, 189 patients (138 male and 51 female), age 8 months to 68 years (mean 31.0+/-4.2 years), underwent aortic valve replacement with a human biological substitute. Of these, 93 patients received a cryopreserved or antibiotic-preserved aortic/pulmonary homograft, whereas 96 patients underwent a Ross procedure. Etiology was rheumatic in 143 (75.6%) patients, bicuspid aortic valve in 40 (21.2%), Marfan's disease in 5 (2.6%), and myxomatous aortitis in 1 (0.5%). Among the homograft group, a scalloped subcoronary implantation technique was used in 54 patients, whereas 32 patients underwent root replacement. Five patients required aortic root and ascending aortia replacement for annuloaortic ectasia. In all patients undergoing the Ross procedure, a root replacement technique was used. Operative mortality was 7.4% (14 patients). Late mortality was 5.3% (10 patients). Follow-up ranged from 1 to 46 months postoperatively. In patients with homograft aortic valve replacement, 76 patients (91.5%) had trivial to mild aortic regurgitation, while 7 patients (8.4%) had important aortic regurgitation. In patients with the Ross procedure, 78 patients (89.6%) had trivial to mild regurgitation. Moderate to severe aortic regurgitation was present in 9 patients (10.3%), all of whom had rheumatic heart disease and were young (< 30 years at surgery). We conclude that homografts and autografts provide an excellent substitute for the diseased aortic valve. Young age (< 30 years) with rheumatic etiology is a major risk factor for early progressive aortic regurgitation in patients undergoing the Ross procedure.     

Treatment of the aortic valve and ascending aorta. The significance of reconstructive methods on the aortic root

BACKGROUND AND OBJECTIVE: The standard surgical repair of disease of the aortic valve and the ascending aorta has been combined replacement, which includes the disadvantage of inserting a mechanical valve. We have investigated an individualized approach which preserves the native valve. PATIENTS AND METHODS: Between October 1995 and October 1997, a consecutive total of 101 patients (72 men, 29 women, aged 21-83 years) underwent operations for disease of the ascending aorta: aortic dissection type A in 34 patients, aneurysmal dilatation in 67. Dilatation of the aortic arch was associated with aortic regurgitation in 58 patients. There were 11 patients with aortic valve stenosis or previously implanted aortic valve prosthesis among a total of 46 whose aortic valve was replaced (group II). Supracommissural aortic replacement with a Dacron tube was performed in 16 patients (group I) with normal valve cusps and an aortic root diameter < 3.5 cm. In 28 patients with an aortic root diameter of 3.5-5.0 cm the aortic root was remodelled (group III). Resuspension of the native aortic valve was undertaken in 11 patients with aortic root dilatation of > 5.0 cm (group IV). RESULTS: Operative intervention was electively performed in 72 patients, without any death. Of 29 patients operated as an emergency for acute type A dissection four died (14%). In 55 of the 58 patients with aortic regurgitation in proved possible to preserve native aortic valve (95%). In the early postoperative phase and after an average follow-up time of 11.8 months, transthoracic echocardiography demonstrated good aortic valve function, except in one patient each of groups III and IV who developed aortic regurgitation grades I or II. CONCLUSION: The described individualized approach makes it possible to preserve the native aortic valve in most patients with aortic regurgitation, at a low risk. Follow-up observations so far indicate good results of the reconstruction.     

Long term growth arrest of human Tenon''s fibroblasts following single applications of beta radiation

Aortic stenosis (AS) is a major risk factor for perioperative cardiac events in patients undergoing noncardiac surgery. We previously showed that selected patients with AS who were not candidates for, or refused, aortic valve replacement could undergo noncardiac surgery with acceptable risk. We extended our previous experience over a subsequent 5-year period by retrospectively analyzing the perioperative course of all patients with severe AS (aortic valve area index < 0.5 cm2/m2 or mean gradient > 50 mm Hg), determined with Doppler echocardiography or cardiac catheterization, who underwent noncardiac surgery. Nineteen patients underwent 28 surgical procedures: 22 elective and 6 emergency. The types of these procedures were 12 orthopedic, 6 intraabdominal, 4 vascular, 4 urologic, 1 otolaryngologic, and 1 thoracic. Mean age was 75 +/- 8 years. Of the 19 patients, 16 (84%) had > or = 1 symptom: dyspnea, angina, syncope, or presyncope. Mean left ventricular ejection fraction was 61 +/- 11%. The type of anesthesia was general in 26 procedures and continuous spinal in 2. Intraarterial monitoring of blood pressure was used in 20 of the 28 surgical procedures. Intraoperative hypotensive events were treated promptly, primarily with phenylephrine. In all cases the anesthesia team was aware of the severity of the AS and integrated this into the anesthetic plan. Two patients (elective operation in 1 and emergency in 1) had complicated postoperative courses and died. There were no other intraoperative or postoperative events in any of the other patients. Although aortic valve replacement remains the primary treatment for patients with severe AS, selected patients with severe AS, who are otherwise not candidates for aortic valve replacement, can undergo noncardiac surgery with acceptable risk when appropriate intraoperative and postoperative management is used.     

Four years' experience of valve replacement with the Bj?rk-Shiley tilting-disc prosthesis

105 valve replacements with the Bj?rk-Shiley tilting-disc prosthesis have been performed in 99 patients with an overall mortality of 12%. The hospital mortality for 73 single aortic valve replacements was 10%, for 24 single mitral valve replacements 13%, and for 5 double valve operations 20%. One late death (1%) occurred in a case with single aortic valve replacement. The follow-up period of the first patients with aortic valve replacement is 4 1/2 years, and that of those with mitral valve replacement over 2 1/2 years. The most common late complication in patients with mitral valve replacement was a paravalvular leak (19%), whereas in patients with aortic valve replacement slight haemolytic anaemia (4%) and late thromboembolism (3%) occurred most frequently. 84 of the 87 survivors showed manifest clinical improvement in their preoperative status and increased exercise tolerance.     

Effect of IciA protein on the expression of the nrd gene encoding ribonucleoside diphosphate reductase in E. coli

BACKGROUND AND AIMS OF THE STUDY: This study investigated the efficacy of postoperative ticlopidine as antiplatelet therapy in patients shortly after heart valve repair or replacement. METHODS: Between 1990 and 1995, 235 consecutive patients underwent either valve repair (n = 67) or replacement with a bioprosthesis (n = 168). The bioprostheses used were Carpentier-Edwards porcine or pericardial (n = 158) valves, Prima stentless valves (n = 3) and cryopreserved homografts (n = 7). Types of repair were aortic (one), mitral annuloplasty with Carpentier ring (65) and tricuspid repair (one). Mean patient age was 67 (range: 16 to 83) years for valve replacement and 57 (range: 32 to 74) years for repair (p < 0.01). Atrial fibrillation occurred in 34% of patients. The hospital mortality rate was 11% (26 patients). Of the 209 survivors, 137 were assigned to antiplatelet treatment with ticlopidine for the first three months of follow up. The other 72 received either oral anticoagulation (coumadin; n = 40), aspirin (n = 14) or no medication (n = 18). In 15 patients, ticlopidine treatment was interrupted due to diarrhea (13 cases), mild allergic reaction (one) or anemia (one). The mean follow up was 3.2 years (range: 1 month to 6 years); cumulative follow up was 684 patient-years (pt-yr) and was complete in 96% of cases. RESULTS: There were two episodes of thromboembolism in the ticlopidine group at 1 month and 6 months respectively, with a linearized incidence of 0.5% pt-yr. In the coumadin group there were four episodes of thromboembolism, three within the first three months of follow up. The linearized incidence was 3% pt-yr (p < 0.01). There were three episodes of hemorrhage in the ticlopidine group in the first three months of follow up and one in the coumadin group. The linearized incidence was 0.75% pt-yr. CONCLUSIONS: Following heart valve repair or replacement with a bioprosthesis, the first three months is a high-risk period for thromboembolism. Ticlopidine seems to prevent this complication better than conventional therapy with oral anticoagulants. Nevertheless, hemorrhage continues to be a problem with ticlopidine therapy.     

Magnesium transport across the basolateral plasma membrane of the fish enterocyte

The aim of the study was to assess the influence of aortic valve replacement on left ventricular size and muscle hypertrophy according to the type of preexisting valve disease (aortic stenosis, insufficiency or combined disease). The study group consisted of 143 consecutive patients (pts) after aortic valve replacement (109 men, 34 women, mean age 48.1 +/- 10.9 years). Reason for the operation was aortic stenosis in 35 pts, aortic insufficiency in 64 pts and combined disease in 44 pts. Echocardiography was performed before surgery, 1 month and 1 year after operation, and yearly during 5-year follow-up. Transvalvular aortic pressure gradients decreased significantly after valve replacement in all subsets without further changes during follow-up (Pmax (mmHg): from 54.2 +/- 20.7 to 17.9 +/- 9.6 in combined disease pts, from 72.3 +/- 19.9 to 21.6 +/- 14.6 in aortic stenosis and from 34.5 +/- 24.2 to 15.6 +/- 11.3 in aortic insufficiency pts, respectively, P < 0.0005). One year after surgery the diastolic dimension of the left ventricle decreased significantly in all subjects, whereas the systolic dimension only in aortic insufficiency and combined disease pts (from 44 +/- 11.8 to 31.6 +/- 5.4 mm, P < 0.001 and from 41.9 +/- 11.5 to 33 +/- 6.7 mm, P < 0.05, respectively). Further decrease of both diastolic and systolic dimensions was observed only in the aortic insufficiency group. Ejection fraction of left ventricle increased only in combined disease pts (from 51.6 +/- 10% to 56.8 +/- 8.2%, P < 0.05). Wall thickness of the left ventricle decreased 1 year after valve replacement only in the aortic stenosis group and in further follow-up in the aortic stenosis and combined disease group. Normalization of left ventricular size is observed in more than 90% of patients during 5-year follow-up as opposed to left ventricular muscle hypertrophy, regressed only in less than a half of the study population. In patients with aortic valve disease the greatest hemodynamic improvement is observed 1 year after valve replacement. This is expressed by marked reduction of the left ventricular dimensions and wall thickness, without significant improvement of the ejection fraction. Further regression of left ventricle dimensions occurs in patients operated on due to predominant valve insufficiency, whereas regression of left ventricular hypertrophy is observed in patients with preexisting valvular stenosis.     

Pulmonary autograft reoperation: incidence and management

BACKGROUND: Pulmonary autograft replacement of the aortic valve is accepted in the young, those with an active life style, and those who are not candidates for anticoagulation. However, concern remains about autograft or homograft valve failure. METHODS: One hundred ninety-five operative survivors of the Ross operation (August 1986 through December 1995) were reviewed for operative pathology and factors associated with reoperation or valve dysfunction. RESULTS: Actuarial freedom from reoperation (autograft or homograft) is 89% +/- 3% at 5 years, 92% +/- 3% for the autograft alone. Early autograft valve failures (< 6 months) were due to technical error in 2 patients and persistent endocarditis in 1. Late autograft valve failure (1 to 6.2 years) was due to aortic annulus dilatation in 5 patients, bacterial endocarditis in 1, and valve degeneration in 2. Six autograft valves were replaced and five were repaired. Five patients required reoperation for pulmonary homograft stenosis (1 to 5.4 years) involving obstruction of the conduit distal to the pulmonary valve. CONCLUSIONS: Pulmonary autograft replacement of the aortic valve has a low incidence of reoperation for autograft dysfunction or homograft obstruction. Autograft dysfunction can be corrected by autograft repair in patients with central insufficiency and aortic annular dilatation.     

Prognosis of asymptomatic or slightly symptomatic chronic aortic insufficiency. Apropos of 54 patients followed for an average of 36 months

A series of 54 patients with chronic aortic insufficiency with little (38) or no symptoms (16) were studied. All had severe regurgitation leading to discussion of aortic valve replacement. All patients (44 male and 10 female) underwent clinical, radiological, electrocardiographic, hemodynamic and angiographic investigation with assessment of left ventricular volume by monoplane 30 degrees cineangiography on entry to the study. They were then followed-up for an average of 36 months and the data assessed in a prospective study. At the end of the 36 months period, 4 patients had been lost to follow-up but were still alive, 31 patients were unchanged (Group A) and 19 patients had deteriorated (Group B). The parameters characterising Group B (P less than 0.001) were: corrected cardiac surface area of 1,72 +/- 0,13, a Sokolow index of 60,1 +/- 18,8 mm an ejection fraction of 56.2 +/- 14 % and a left ventricular end diastolic value of 225,3 ml/m2. Therefore, in chronic asymptomatic aortic incompetence, the parameters of cardiac dilatation, cardiac surface area greater than 1,70 and left ventricular end diastolic volume greater than 170 ml/m2, would appear to be good indications for aortic valve replacement. However, the values are nor formal criteria because a discrepancy between symptoms and the volumetric measurements may be observed in some cases, and also large variations in these measurements may be observed in patients in the same functional class.     

Pregnancy in patients with pulmonary autograft valve replacement

AIM: The purpose of this study is to determine the outcome and complications of pregnancy in women with pulmonary autograft valve replacement for aortic valve disease. METHODS AND RESULTS: The records of all women who had undergone pulmonary autograft valve replacement at the National Heart Hospital (now Royal Brompton Hospital) since 1968 were reviewed. From 1968 to 1993, 27 hospital survivors were female and among eight of them there were 14 pregnancies. All women were in Ability Index 1 at time of pregnancy with normal ventricular function, mild aortic regurgitation (six), mild pulmonary regurgitation (three) and mild pulmonary stenosis (two). None took anticoagulants. There was no maternal death, thromboembolic or haemorrhagic event or evidence of deterioration in valve function during pregnancy. Except for one woman (Ability Index 3) who developed dilated cardiomyopathy without aortic or pulmonary valve disease 6 months after delivery, the women remained in Ability Index 1 after pregnancy. There was no significant progression of aortic regurgitation (mild after seven pregnancies), pulmonary regurgitation (mild after six) or right-sided obstruction (mild after four). Reoperation for right-sided obstruction was carried out in two patients 4 and 7 years after a second pregnancy (9 and 15 years after the pulmonary autograft). CONCLUSION: No valve-related complications occurred during pregnancy and pregnancy appeared to have no effect on the function of the pulmonary valve autograft or the right-sided homograft. The pulmonary autograft is thus an ideal procedure for a young female needing aortic valve replacement.     

Mobilization of the left and right fibrous trigones for relief of severe left ventricular outflow obstruction

BACKGROUND: There is still no agreement about the optimal method of surgical relief of fixed subaortic stenosis, particularly the severe forms. OBJECTIVES: The purpose of this study was to describe a new technique for the relief of subaortic stenosis based on analysis of the functional anatomy of the left ventricular outflow tract and pathophysiologic features of subaortic stenosis. Methods and patients: We propose that one of the basic abnormalities in subaortic stenosis is interference with the hinge mechanism provided by the 2 fibrous trigones with progressive deposition of fibrous tissue in these angles. The technique described in this paper consists of excision of all components of the fibrous "ring," with mobilization of the left and right fibrous trigones. This results in the restoration of the normal dynamic behavior of the left ventricular outflow tract with maximal widening of the outflow tract as the result of backward displacement of the subaortic curtain and anterior leaflet of the mitral valve. This technique has been used in 57 consecutive patients who ranged in age between 5 months and 56 years (mean, 15.5 +/- 10.6 years). Gradients across the left ventricular outflow tract were between 45 and 200 mm Hg (mean, 86.7 mm Hg). Additional lesions were present in 10 patients, and 7 patients had had 8 previous operations on the left ventricular outflow tract. At operation, in addition to resection of subaortic stenosis, 3 patients had aortic valvotomy, 2 patients had homograft replacement of the aortic valve, 7 patients had patch closure of a ventricular septal defect, and 1 patient had open mitral valvotomy. RESULTS: There were 2 early deaths and 1 late sudden death during the follow-up period that ranged from 1 month to 25 years (mean, 15. 2 years). One patient experienced the development of endocarditis on the aortic valve 7 years after operation, which was successfully treated by homograft replacement. Postoperative gradients across the left ventricular outflow tract varied from no gradient to 30 mm Hg (mean, 8 mm Hg). There were no instances of recurrence of a gradient across the left ventricular outflow tract. CONCLUSION: It is concluded that mobilization of the left and right fibrous trigones results in durable relief of subaortic stenosis.     

Upper T mini-sternotomy for aortic valve operations

OBJECTIVES: New minimally invasive approaches for cardiac surgical procedures are constantly being developed in the hope of decreasing patient morbidity and enhancing the postoperative recovery. This report reviews the use of an upper T mini-sternotomy approach to aortic valve surgery. PATIENTS: Nine consecutive nonselected patients (5 men, 4 women, mean age, 66 years) underwent isolated aortic valve replacement with the use of this approach. Two patients had isolated aortic valve stenosis, three had isolated aortic valve incompetence, and four patients had mixed aortic valve disease. RESULTS: In all cases, an excellent view of the aortic valve was obtained, aortic valve replacement with a bileaflet mechanical prostheses was performed, and no intraoperative difficulties were encountered. Mean aortic cross-clamp time was 83 min and mean cardiopulmonary bypass perfusion time was 97 min. All patients were extubated in the operating room at the end of the surgical procedure, and there were no postoperative complications. All patients were discharged home on postoperative day 3, and there were no late complications. CONCLUSION: Through an upper T mini-sternotomy, aortic valve surgery can be performed in the conventional manner using standard surgical instruments with no alteration in cardiopulmonary bypass and myocardial protection routines. With this method, postoperative pain is reduced and patient recovery is expeditious.     

The reaction of nerve tissue to various suture materials: a study in rabbits

A series of 12 consecutive patients who underwent aortic valve replacement (AVR) for aortic stenosis complicated by severe left ventricular dysfunction was reviewed. Ventricular dysfunction was reflected by pulmonary congestion, edema, renal and hepatic dysfunction, and by severely depressed ejection fractions (mean, 13%; range equal to 0-20%). Aortic valve replacement was accompanied by mitral commissurotomy in 1 patient and aortocoronary bypass in 5. Three of 5 patients with greater than 50% coronary obstruction died without reversal of heart failure, and 1 of the 5 died after a stroke. The 1 survivor of this group has done well. All 7 patients with minimal or no coronary disease survived operation and are now in New York Heart Association Class I or II. Postoperative catheterization (2 to 12 months) in 6 patients showed improved cardiac index and filling pressures. Left ventricular diastolic volume fell from 159 to 82 ml/m2, and ejection fraction rose from 13 to 45%. We conclude that left ventricular dysfunction owing to aortic stenosis alone is reversible and that AVR results in great clinical improvement. When coronary disease is present, survival may be accompanied by great improvement but the operative mortality is much higher.     

Left main coronary artery stenosis following aortic valve replacement using a solid coronary perfusion catheter: report of two cases

We experienced two cases of iatrogenic left main coronary artery stenosis (IOCS) following double (aortic and mitral) valve replacement (DVR). The solid coronary perfusion catheter may attribute IOCS, with grave consequence. There have been no IOCS since the time we exchanged a solid catheter for a soft one. One case, she was successfully treated percutaneous transluminal coronary angioplasty (PTCA), because she developed angina pectoris about 5 years after PTCA. But she developed angina pectoris again and angiographically left main coronary was severe stenotic. So she was undergone aorto coronary bypass grafting (CABG) to the left anterior descending. The other case, he developed angina pectoris about 3 months after DVR. He was treated with PTCA. Angiographically left mine coronary artery stenosis reduced 50% from 90%. Generally the treatment of IOCS is CABG, but we performed PTCA for 2 patients. Because we thought it was very hazardous for us to perform them open heart surgery. When it is very hazardous to perform patients open heart surgery, they need to be performed PTCA.     

Regression of left ventricular hypertrophy after aortic valve replacement for aortic stenosis with different valve substitutes

OBJECTIVE: Stentless biologic aortic valves are less obstructive than stented biologic or mechanical valves. Their superior hemodynamic performances are expected to reflect in better regression of left ventricular hypertrophy. We compared the regression of left ventricular hypertrophy in 3 groups of patients undergoing aortic valve replacement for severe aortic stenosis. Group I (10 patients) received stentless biologic aortic valves, group II (10 patients) received stented biologic aortic valves, and group III (10 patients) received bileaflet mechanical aortic valves. METHODS: Echocardiographic evaluations were performed before the operation and after 1 year, and the results were compared with those of a control group. Left ventricular diameters and function, left ventricular wall thickness, and left ventricular mass were assessed by echocardiography. RESULTS: Group I patients had a significantly lower maximum and mean transprosthetic gradient than the other valve groups (P = .001). One year after operation there was a significant reduction in left ventricular mass for all patient groups (P < .01), but mass did not reach normal values (P = .05). Although the rate of regression in the interventricular septum and posterior wall thickness differed slightly among groups, their values at follow-up were comparable and still higher than control values (P = .002). The ratio between interventricular septum and posterior wall and the ratio between wall thickness and chamber radius did not change significantly at follow-up. CONCLUSIONS: Because the number of patients was relatively small, we could not use left ventricular mass regression after I year to distinguish among patients undergoing aortic valve replacement for aortic stenosis by means of valve prostheses with different hemodynamic performances.