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Aortic valve damage caused by operative balloon dilatation of critical aortic valve stenosis.

Operative balloon dilatation of the aortic valve was performed in seven neonates with critical stenosis of the aortic valve. The procedure was followed by the development of severe aortic regurgitation in four patients. Necropsy was performed in three and revealed partial detachment of the right coronary cusp of the aortic valve. Damage to the valve leaflet caused by balloon dilatation was probably the result of using a balloon with a diameter that was too large in relation to the aortic valve ring diameter and of shearing forces created in the aortic wall by the contracting ventricle. The diameter of the inflated balloon should not be larger than the diameter of the aortic valve ring.

Angioplasty, Balloon↗

Patient outcome and valve performance following a second aortic valve homograft replacement.

BACKGROUND: Homograft valves offer many advantages; however, there is concern about their use in second aortic valve replacement because of the complexity of the procedure and the possibility of accelerated degeneration. METHODS AND RESULTS: One hundred and forty-four patients underwent a second aortic homograft replacement between 1973 and 1997 (mean follow-up 6.5+/-5 years, range 1 to 20 years). Eighty-three were male, and 61 were female, aged 17 to 77 years, mean 49.0 years. All patients had undergone previous aortic valve replacement with a homograft. The indication for reoperation was aortic regurgitation in 75 patients (52.1%), aortic stenosis in 28 (19.4%), and mixed aortic valve disease in 41 (28.5%). Root replacement was performed in 54 patients (38%) and subcoronary in 90 (62.5%). Early mortality was 3.4%. The actuarial survival rate was 93% and 82% at 5 and 10 years, respectively. Freedom from tissue degeneration was 96% and 80% at 5 and 10 years, respectively, and freedom from reoperation was 97% and 82% at 5 and 10 years, respectively. CONCLUSIONS: This study shows that a second aortic valve homograft replacement results in good early and long-term survival. Accelerated degeneration does not occur. Left ventricular performance is improved, and earlier surgery could further improve outcome, indicating that an aortic homograft is a safe, durable option for patients requiring a second aortic valve replacement.

Adolescent↗

Diastolic stiffness and myocardial structure in aortic valve disease before and after valve replacement.

Passive diastolic properties were determined in 10 control patients and 21 patients with aortic valve disease before and 17.5 months after successful valve replacement. Ten patients had severe aortic stenoses (AS), five had combined aortic valve lesions (AS + aortic insufficiency [AI]), and six patients had severe AI. Left ventricular endomyocardial biopsies were obtained before and after surgery in patients with AS, AS + AI, and AI. Simultaneous echocardiographic and high-fidelity pressure measurements were made in all patients, and left ventricular chamber stiffness was calculated from a viscoelastic pressure-circumference relationship and left ventricular myocardial stiffness from a viscoelastic stress-strain relationship. The constant of chamber stiffness, beta', was slightly although not significantly increased in patients with AS (0.27 before and 0.24 after surgery), but was normal in those with AS + AI (0.22 before and 0.17 after surgery) and slightly decreased in those with AI (0.18 before and 0.16 after surgery) when compared with in control subjects (0.21). The constant of myocardial stiffness beta was normal in patients with AS (13.2), AS + AI (11.5), and AI (11.7) before surgery compared with in the control group (12.5). beta increased, however, significantly in those with AS (25.2; p less than .02), but not in those with AS + AI (16.3; NS) and AI (12.8; NS) after surgery. Myocardial morphologic characteristics showed a significant decrease in muscle fiber diameter in patients with AS, AS + AI, and AI, as well as a significant increase in interstitial fibrosis from 15% to 26% (p less than .05) in those with AS and a slight increase from 15% to 22% (NS) in those with AS + AI and from 19% to 24% (NS) in those with AI. Left ventricular fibrous content (left ventricular muscle mass index multiplied by interstitial fibrosis) remained, however, unchanged in all three groups after aortic valve replacement. In conclusion, left ventricular chamber stiffness is increased in AS but decreased in AI, whereas LV myocardial stiffness is normal in patients with aortic valve disease before surgery. After surgery, left ventricular myocardial stiffness increased significantly in AS patients but remained unchanged in those with AI. Postoperative changes in myocardial structure were characterized by a decrease in muscle fiber diameter and a relative increase in interstitial fibrosis, whereas fibrous content remained unchanged. Thus, regression of myocardial hypertrophy in aortic valve disease is accompanied by an increase of myocardial stiffness in concentric hypertrophy that is not seen in eccentric hypertrophy.

Adult↗

[A case of minimal invasive aortic valve replacement for quadricuspid aortic valve with aortic regurgitation].

Congenital quadricuspid aortic valve is rare, which may be a cause of sever aortic regurgitation. We report a case of a 55-year-old man who had severe aortic regurgitation with congenital quadricuspid aortic valve. Preoperative aortography showed severe aortic regurgitation. Preoperative trans-esophageal echocardiography revealed abnormal quadricuspid aortic valve. We performed minimal invasive aortic valve replacement with SJM # 21 mm HP prosthetic valve through the limited upper sternotomy. Skin incision was 9 cm. Aortic cross-clamping time was 92 min, cardiopulmonary bypass time was 108 min. At the operation, a quadricuspid valve with three equal cusps and one small cusp was noted. The postoperative course was excellent and he discharged 8 days after the operation.

Aortic Valve↗

Ventricular septal defect complicated by infective endocarditis of the aortic valve causing severe aortic regurgitation: the role of aortic valve repair.

BACKGROUND AND AIMS OF THE STUDY: Children with ventricular septal defect (VSD) who develop severe aortic regurgitation following infective endocarditis (IE) require aortic valve replacement in most cases. Few reports exist of repair of the aortic valve under such circumstances. Here, we report details from two patients in whom aortic valve repair resulted in a good outcome. METHODS: Two children (aged 4 and 3 years) with either perimembranous or doubly committed subarterial VSD presented with congestive cardiac failure (NYHA class IV) following IE. The aortic valve in both children, and the pulmonary valve in one child, were severely damaged with vegetation, leading to severe (grade IV) aortic regurgitation. The second patient had bilateral bronchiectasis with respiratory infection and severe anemia. In addition to VSD closure, partial cuspal replacement using glutaraldehyde-tanned pericardium was performed successfully in both cases to restore geometry. RESULTS: Both children showed a dramatic improvement following surgery and during follow up of 36 and 11 months, respectively. Both remained asymptomatic, with good growth, good left ventricular function and the presence of only trivial aortic regurgitation. CONCLUSION: In selected patients with suitable anatomy, repair of the aortic valve with pericardial cusp replacement may be the procedure of choice. An additional benefit is the avoidance of long-term anticoagulation.

Aortic Valve↗

Economic impact of mitral valve plasty versus replacement for mitral valve insufficiency.

AIM: The principal techniques for surgical correction of mitral valve regurgitation (MR) were compared, with emphasis on the economic impact. METHODS: In a prospective non-randomized study 225 patients undergoing mitral valve repair were analyzed, 75 had mitral valve plasty (MVP) and 150 had mitral valve replacement (MVR). Patient demographics showed no group differences. RESULTS: Cardiopulmonary bypass time and ischemia time were shorter in the MVP-group, p<0.0001. Hospital mortality was lower after MVP, 2.0% (3/150) compared to MVR, 6.7% (5/75). ICU-stay was shorter in the MVP-group and so was length of postoperative hospital stay, p=0.014. Urgent operation was the only significant risk factor for mortality after MVP. Re-operation, endocarditis, grade IV MR, and NYHA class IV were additional risk factors in the MVR-group. Postoperative improvements of NYHA and mitral valve function were similar in both groups. MVP was more cost effective than MVR (18,050 USD or 20,430 Euro versus 24,824 USD or 28,097 Euro, p<0.001). CONCLUSION: Mitral valve plasty for MR is efficient and associated with shorter CPB and ischemia times as well as length of stay in ICU, together with a lower device cost, which makes MVP more cost effective than MVR.

Aged↗

Porcine or human stentless valves for aortic valve replacement? Results of a 10-year comparative study.

BACKGROUND AND AIM OF THE STUDY: Stentless porcine valves in the aortic position exhibit similar excellent hemodynamic performance to homografts, but have the advantage of availability. Their performance was compared over a 10-year period in a single-surgeon and single-institution series. METHODS: Demographic, operative and mortality data were obtained retrospectively. Survivors were interviewed by telephone according to a defined protocol. Definitions and analyses were in accordance with joint STS/AATS guidelines. RESULTS: A total of 408 stentless porcine and homograft aortic valve replacements (AVR) was performed between 1991 and 2001. Five patients were excluded due to incomplete data, in addition to 82 patients who underwent AVR with a free-standing root replacement technique. Hence, 321 patients (217 males, 104 females; mean age 67 +/- 12 years) had a subcoronary implant. The median time to follow up was 4.9 years (range: 2.9-6.6 years). No differences were noted between homograft and stentless porcine valves in one- and five-year freedom from structural valve deterioration (99.1 versus 97.2% and 95.7 versus 93.1%; p = 0.10), reoperation (99.2 versus 99.4% and 97.8 versus 96.7%; p = 0.45) and endocarditis (98.3 versus 99.4% and 97.4 versus 99.4%; p = 0.14). Overall one- and five-year survival comparing homograft to stentless porcine valve was 90.4 versus 92.3% and 80.8 versus 73.7%, respectively; p = 0.23. Independent predictors of mortality on multivariate analysis were: ventricular function (p < 0.0001), increasing age (p < 0.001), increasing serum creatinine (p < 0.001) and concomitant coronary surgery (p = 0.05). Treated hypercholesterolemia was independently protective against mortality, with an odds ratio of 0.26 (CI 0.10 to 0.66; p = 0.005). CONCLUSION: The porcine stentless valve, when implanted in the subcoronary position, is an excellent alternative to the homograft and shows excellent clinical performance and durability at mid term.

Age Factors↗

[Corrected transposition of the great arteries with associated tricuspid valve incompetence--report of a case of successful tricuspid valve replacement].

A 36-year-old woman with corrected transposition (C-TGA) of great arteries with associated systemic atrioventricular valve (A-V valve) regurgitation was presented. Cineangiography revealed that the right sided ventricle was morphologic left ventricle, and left sided ventricle was morphologic right ventricle. In addition, severe systemic A-V valvular regurgitation (Sellers IV) was demonstrated. Under the diagnosis of C-TGA with associated A-V valvular regurgitation, left sided atrioventricular valve replacement was performed using 29 mm SJM valve. Left sided atrioventricular valve was tricuspid valve (TV). A part of the anterior tricuspid leaflet and two pieces of papillary muscle was resected. Postoperative course was uneventful. The pathological findings indicated that valvular tissue had myxomatous degeneration.

Adult↗

[Pure aortic valve regurgitation due to congenital bicuspid valve--analysis of 7 cases and a report of 2 rare cases].

The congenital bicuspid aortic valves usually become stenotic with severe calcification or regurgitant due to infective endocarditis (IE). However, pure aortic valve regurgitation without calcification or IE may be occurred. We report seven these cases out of 30 bicuspid valved patients who underwent aortic valve replacements. Pathological findings of these resected valves revealed neither calcium deposit nor findings of infection, but commonly showed myxoid degeneration. They were operated on at the mean age of 39, while those with calcified bicuspid aortic valves had an average age of 56. Two rare cases in whom an anomalous fibrous band on the larger cusp attached to the aortic wall were also reported.

Adult↗

[Aortic valve replacement for rheumatoid aortic valve regurgitation].

Valve replacement for aortic regurgitation in patient with rheumatoid arthritis was rare in Japan. We report a successful case in which aortic regurgitation necessitated aortic valve replacement. A 62-year-old woman was admitted for shortness of breath, chest pain and progressive edema. She had been treated for rheumatoid arthritis for more than ten years using steroids. The aortic valve was successfully replaced by a prosthetic mechanical valve. The histopathological examination of the excised aortic valve demonstrated rheumatic nodules in the right- and non-coronary cusp. It was supported that these changes caused shrinkage of cusp and resulted in aortic regurgitation. This patient was discharged on the 20th postoperative day. There was no evidence of detachment of the prosthetic valve.

Anti-Bacterial Agents↗

The long-term results of mitral valve reconstruction for the "floppy" valve.

The myxomatous degenerated, prolapsed, or floppy mitral valve is the most common etiology of mitral regurgitation in North American populations. We performed mitral valve reconstruction for this diagnosis in 252 patients from 1984 to 1993. There were 165 males and 87 females ranging in age from 23 to 84 years (mean 64 years); 93 (37%) were > or = 70 years. One hundred eighty-six were New York Heart Association Functional Class III or IV and 29% (72) underwent concomitant coronary bypass operation. Operations included posterior leaflet resection, anterior leaflet resection treatment of chordal pathology by shortening or Gore-Tex replacement, and ring annuloplasty. There were five operative deaths for an operative mortality of 2%. The operative risk in patients under 70 years was 1 of 159 (0.6%) and 4 of 93 (4%) in patients older than 70 years. Ninety percent of patients are asymptomatic in a follow-up period extending 10 years, while structural valve degeneration requiring reoperation at 5 years was 85%. From 1990 to 1993 there has been a less than 5% absolute incidence of structural valve degeneration. Mitral valve reconstruction for complicated floppy mitral valve is feasible and offers excellent early and medium-term results.

Adult↗

Aortic valve replacement for quadricuspid aortic valve incompetence.

Quadricuspid aortic valve is an uncommon cause of aortic regurgitation. We report two patients who underwent aortic valve replacement because of severe aortic incompetence; the presence of a quadricuspid aortic valve was an accidental surgical finding. In one patient the aortic valve comprised two equal-sized larger cusps and two equal-sized smaller cusps, while in the other it comprised three cusps of similar size and a small accessory cusp between the right and non-coronary cusps. This report confirms the rarity of the disease and the fact that patients with quadricuspid aortic valves characterized by cusps of different sizes are more prone to develop progressive aortic incompetence because of unequal distribution of stresses on the valve. Therefore, such patients should undergo periodic, life-time echocardiographic assessment once this malformation is detected.

Aged↗

Evaluation of the functional significance of the colorectal valve used in rectal urinary diversion in children: a comparative study between cases with and without the valve.

OBJECTIVES: To study the long-term impact of functional isolation of rectal reservoirs on the blood chemistries and acid-base balance of children who underwent this type of urinary diversion. METHODS: A retrospective evaluation of 63 children with rectal reservoirs was performed. Of these, 40 had a colorectal valve and 23 had double-folded rectal reservoirs without a functional isolation valve. Evaluation included serum chemistry and arterial blood sample analysis to verify the impact of the created valve on homeostasis. RESULTS: There was a statistically significant difference between the two groups relative to the value of pH, P(CO2), bicarbonate, base excess, and chloride in favor of those having a colorectal valve. Reduction of the absorptive surface area of the colon is presumably the cause in view of the functional isolation created by the colorectal valve. CONCLUSIONS: In children, the long life expectancy and the benign condition for which they have diversion require the incorporation of the colorectal valve in any form of continent rectal diversion. Prophylactic alkalinization with strict follow-up is a must in those having no valve.

Acid-Base Equilibrium↗

Hydrostatic characteristics of the ileocolic valve and intussuscepted nipple valves: an animal model.

The ileocolic valve, in the dog, decelerates the passage of stools and prevents fecal reflux. A loss of anterograde resistance worsens the symptoms of short bowel syndrome. The absence of fecal reflux control enhances the risk of recurrence of Crohn's disease. The aim of the present study was to examine what length of intussusception-like nipple valve (INV) should be constructed in order to restore the hydrostatic characteristics of the normal ileocecal valve. The anterograde and retrograde hydrostatic resistances of INVs of different lengths (4, 5, 6, or 7 cm) were compared with those of the normal ileocolic valve by using a contrast enema and x-ray monitoring in a canine model. It was found that the 4-cm-long INV may be sufficient to achieve an appropriate antireflux efficacy (59.60 +/- 4.26 cm H(2)O) versus the ileocolic valve (25.80 +/- 4.92 cm H(2)O), but this does not furnish an anterograde resistance comparable to that of the normal ileocolic valve (10.70 +/- 1.15 cm H(2)O vs. 21.60 +/- 3.96 cm H(2)O). We found that the appropriate length of the INV with which the anterograde resistance of the ileocolic valve could be attained in our model was between 6 and 7 cm. Thus, the shortest possible constructed INV should be effective in clinical conditions such as Crohn's disease, but the recommended length in short bowel syndrome should be greater than this.

Animals↗

A percutaneous approach to deep venous valve insufficiency with a new self-expanding venous frame valve.

PURPOSE: To ascertain if a percutaneously delivered venous valve bioprosthesis (PVVB) can be implanted in the porcine venous system and function without complications. METHODS: The PVVB is a glutaraldehyde-preserved, valve-bearing venous xenograft sutured inside a memory-coded nitinol frame (diameter 10, 12, or 14 mm). In 10 50-kg pigs, the external jugular vein was exposed, and a 16-F introducer sheath was positioned in the common iliac vein. One PVVB was inserted and deployed in each iliac vein under fluoroscopic control. After PVVB implantation, all animals were randomly given either vitamin K antagonists (1-2 mg/d) (group I) or a combination of aspirin (150 mg/d) and clopidogrel (75 mg/d) (group II), which were shown in a preliminary pilot study to be the most effective anticoagulation regimens in the pig model. Ascending and descending completion phlebograms were performed. PVVBs were evaluated with phlebography at 4 weeks to assess patency and competence; all PVVBs were explanted and processed for histological analysis. RESULTS: In 8 animals, the PVVB was successfully deployed in both the left and right iliac veins. In 2 pigs, only 1 PVVB was inserted due to vascular anomalies. Completion phlebography demonstrated 18 patent and competent valves. At 2 weeks, bleeding complications occurred in 3 group I pigs; all 5 animals were terminated to prevent further complications. Of the 8 valves in this group, 7 were patent (3 competent) by phlebography; 1 PVVB had migrated due to known undersizing of the stent frame. At 4 weeks, group II (5 pigs, 10 valves) analysis revealed 5 patent (3 competent) valves; no bleeding complications occurred in this group. Histology showed thrombosis as the cause of occlusion in all 5 non-patent valves from group II. CONCLUSIONS: Deployment of a glutaraldehyde-fixed bovine vein sutured to a self-expanding nitinol stent in the porcine iliac vein is technically feasible. Development of a venous bioprosthesis that can be placed percutaneously may have important clinical applications as an endovascular treatment for chronic venous insufficiency when it is due to valvular incompetence.

Animals↗

Harken caged-disc mitral valve replacement, 1969-1975: analysis of late mortality, thromboembolism, and valve failure.

We evaluated the long-term outcome of mitral valve replacement with a Harken caged-disc prosthesis for up to 11 years (range, 50 to 130 months; mean, 81 months) in 170 patients whose mean age was 55 years. The early (30-day) mortality was 11.2% (19 out of 170 patients). Late follow-up information was obtained for 144 (95%) of the 151 survivors. The actuarial survival was 57% at 5 years and 40% at 10 years. Overall mortality was associated with advanced age, male sex, an ischemic origin for the mitral valve disease, and nonuse of warfarin anticoagulation. Late deaths (n=59) were valve-related in 46%, cardiac but non-valve-related in 44%, and noncardiac in 10% of the cases. One thromboembolic event or more occurred in 41 patients (incidence, 5.7% per patient year), 14 of whom died (24% of the late deaths). All four patients who were not on warfarin, aspirin, or other antithrombotic therapy experienced thromboemboli. This complication was correlated with the nonuse of warfarin-type anticoagulation, with mitral regurgitation, and with late cardiac death. Mechanical prosthetic failure resulted in reoperation or death in 7.6% of the late survivors (1.5% per patient year). In 75 patients with normally functioning prostheses, the disc-to-sewing ring ratio was established by means of cinefluoroscopy (0.93 +/- 0.04, mean +/- 25D). Because of the high proportion of cardiac valve-related deaths (46%), the high incidence of late mortality due to thromboembolic events (24%), and the 7.6% incidence of reoperation or death resulting from mechanical valve failure, close follow-up with cinefluoroscopy and continued warfarin anticoagulation (alone or in combination with dipyridamole) are essential after mitral valve replacement with the Harken caged-disc prosthesis.

Journal Article↗

Imperforate tricuspid valve with dysplasia of the right ventricular myocardium, pulmonary valve, and coronary artery: a clinicopathological study of nine cases.

Nine cases of imperforate tricuspid valve associated with dysplasia of the right ventricular myocardium, pulmonary valve, and right coronary artery are described. The mean frontal QRS axis of the electrocardiograms did not indicate left axis deviation in seven of the nine. Two-dimensional echocardiograms showed an imperforate tricuspid valve, normally aligned atrioventricular septum, and an irregular-shaped right ventricular cavity with a thin wall. In three cases with absence of the pulmonary valve, pulsed Doppler echocardiograms of the right ventricular outflow tract revealed antegrade flow during systole and retrograde flow during diastole, and selective angiography through a persistent ductus arteriosus showed retrograde filling of the blind-ended right ventricular cavity via the main pulmonary artery. Necropsy examinations showed an imperforate tricuspid valve with a thin-walled aneurysmal right ventricle in all six cases examined. Pulmonary atresia was observed in two cases, and the absence of the pulmonary valve in four. The right coronary artery was hypoplastic in four cases and absent in two. A shunt operation should be carried out in early infancy to prevent hypoxia after closure of the ductus arteriosus.

Abnormalities, Multiple↗

"Balloon valvulotomy" of congenital pulmonary valve stenosis with tricuspid valve insufficiency.

The rare congenital anomaly of pulmonary valve stenosis and massive tricuspid valve insufficiency with intact ventricular septum is a lethal condition without reported survival after attempted treatment. In a neonate suffering from this syndrome, the pulmonary valve stenosis was relieved by rupturing the fused valve with a balloon catheter introduced transvenously. The desperate condition of the patient quickly improved after this procedure, with subsequent disappearance of the tricuspid valve incompetence. Balloon rupturing of fused valves at angiography may represent a therapeutic alternative in cases in which surgical valvulotomy is associated with a high mortality.

Cardiac Catheterization↗