[Mitral valve and aortic valve diseases--valvoplasty and valve replacement].
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Adult↗
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[Long -term follow-up study on clinical and hemodynamic results of mitral valve replacement for acquired mitral valve desease with Starr-Edwards ball valve (author's transl)].
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Adolescent↗
Factors influencing the results of double-valve surgery in patients with fulminant endocarditis: the importance of valve selection.
BACKGROUND: Extension of infection below the aortic valve is a serious complication, especially with mitral valve involvement. Mortality is substantial and reinfection can strongly influence outcome. PATIENTS: Of 327 surgical patients with active infective aortic valve endocarditis admitted to the Deutsches Herzzentrum Berlin for surgical treatment between December 1996 and December 2003, 108 had root abscess, and 53 (25.5%) had diagnoses of secondary infective mitral valve disease (SMVD). The mean age (+/-SD) was 53 +/- 14.2 years; there were 37 men and 16 women. METHODS: The secondary lesion on the mitral valve was classified as SMVD requiring double-valve surgery (DVS). This prospective clinical and echocardiographic study revealed 2 paths of infection extension into the mitral valve. In the DVS group, 38 patients (71.7%) had tissue metastatic lesions, and 15 patients (28.3%) had a jet lesion on the mitral valve. Most patients (42) with SMVD had an aortic ring abscess as the primary lesion. RESULTS: All patients with destructive endocarditic doublevalve disease received aortic and mitral valve surgery. In 19 cases (35.8%), mitral valve reconstruction was undertaken; in 4 cases, mitral valve replacement had to be carried out after attempted mitral valve reconstruction. Concomitant mitral valve replacement because of severe damage to the valvular and subvalvular apparatus was performed in 30 patients (56.6%). Other types of surgery performed in 11 cases (20.8%) were 8 closures of a septic ventricular septal defect and 3 closures of a fistula to the right ventricle or right atrium. Twenty-seven patients were treated with a Shelhigh prosthesis, 18 were treated with double-valve replacement (both Shelhigh), and 9 were treated with an aortic Shelhigh prosthesis and concomitant mitral valve reconstruction. Homografts were used in 17 patients, with mitral valve reconstruction carried out in 10 patients and a stented mitral prosthesis in 7. In 9 cases, 2 stented valve prostheses were used. There were 14 early (60 days) deaths (26.4%). Septic shock, severe annular and subannular destruction, and poor left ventricular function (end-diastolic dimension >65 mm, ejection fraction <40%) were the significant risk factors determined in the multivariate analysis. Function of Implants: Continuous and Color Doppler Investigation: Comparative studies of 2 different implants in the aortic position were performed late postoperatively (325 +/- 251 days) for homografts and the Shelhigh stentless prosthesis. The calculated instantaneous (maximal Doppler) gradient and the mean pressure gradient through the aortic implants were 19 +/- 10.4 mm Hg and 12 +/- 5.7 mm Hg, respectively, for the homografts and 24 +/- 8.4 mm Hg and 15 +/- 4.6 mm Hg, respectively, for the Shelhigh stentless prosthesis (not significantly different for the 2 groups). There was no mitral or aortic valve dysfunction. A trivial paravalvular leakage in the mitral position in 1 patient and a pseudoaneurysm of the left ventricular out- flow tract without leakage or valvular dysfunction in another were diagnosed by postoperative Doppler investigation. CONCLUSIONS: The mortality in patients with destructive endocarditis requiring DVS depends mostly on the patients' preoperative hemodynamic situation. The risk of reinfection can be minimized if valve substitutes are properly selected (homografts, Shelhigh No-React SuperStentless and No-React BioConduit in the aortic position, or Shelhigh BioMitral in the mitral position). Concomitant mitral valve reconstruction procedures do not increase the risk of mitral reinfection.
Endocarditis↗
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.
Adolescent↗
Clinical results of pericardial xenograft valves: the Ionescu-Shiley and Hancock valves.
Between 1979 and 1985, 552 Ionescu-Shiley valves were implanted in 511 patients. The Hancock valve was implanted in 122 patients (129 valves) between 1982 and 1983. Sixty percent of procedures were isolated aortic valve replacements. In the Ionescu series, 59% of these were 19 or 21 mm valves while only 15% of the Hancock valves were of this size. For isolated mitral valve replacement, 76% of Ionescu-Shiley valves were 25 to 27 mm, compared to 36% of the Hancock valves. Patient age, sex, prior operations, concomitant surgery (usually coronary bypass), operative mortality and late deaths were similar for both valves. A mean follow-up of 38 months was obtained for each valve population (99% complete) representing a cumulative 1497 patient-years for the Ionescu-Shiley valve and 375.4 patient-years for the Hancock valve. Actuarial survival for the former was 73 +/- 4% at 72 months, and 65 +/- 14% for Hancock valves at 60 months. The frequency of major events during follow-up (thromboembolism, anticoagulant related hemorrhage, bland perivalvular leak and prosthetic valve endocarditis) were similar, but the frequency of primary tissue valve failure was markedly different for the two valves (1.1% per patient-year for Ionescu-Shiley valves and 5.9% for the Hancock valve). The mean interval to replacement of an Ionescu mitral prosthesis was significantly shorter (23.4 months) than for replacement of an aortic prosthesis (42 months) while the mean interval to replacement of an Ionescu aortic and/or a Hancock aortic or mitral were all similar.(ABSTRACT TRUNCATED AT 250 WORDS)
Actuarial Analysis↗
[Current aspects of mitral valve repair in the surgical treatment of mitral valve insufficiency].
Mitral valve repair (MVR) is the golden standard for the surgical treatment of mitral valve regurgitation and is superior to mitral valve replacement in terms of perioperative and long-term morbidity and mortality. However, the underlying disease has a significant impact on the functional long-term result of the repair. To evaluate the results of MVR, patients have to be divided by the underlying disease, degenerative mitral valve regurgitation, rheumatic mitral valve regurgitation, ischemic mitral valve regurgitation, and mitral valve regurgitation due to advanced cardiomyopathy. The best functional result for MVR can be achieved for degenerative mitral valve regurgitation (10-year freedom from reoperation for recurrent mitral regurgitation up to 94%) followed by patients with rheumatic mitral valve regurgitation (10-year freedom from reoperation for recurrent mitral regurgitation up to 82%). The progress in the underlying disease of the mitral valve is responsible for recurrent mitral valve regurgitation in these patients. For both underlying disease the 10-year survival rate is > 75%. For patients with ischemic mitral valve regurgitation the functional and survival rates are worse with a 5-year survival rate < 60% and recurrent mitral valve regurgitation > MI (mitral valve insufficiency) II degrees in 28% of patients within 6 months. However, ischemic mitral valve regurgitation is not a disease of the valve, it is a disease of the myocardium; thus, the myocardium is the key factor influencing the functional results of MVR and not pathologic changes in the mitral valve per se. There are no long-term results on patients operated on MI in conjunction with advanced cardiomyopathy; however, the initial mid-term results are encouraging with improved survival. Besides the underlying disease the timing of surgery is of utmost importance for the long-term survival; patients with preoperative NYHA functional class III/IV have a significantly worse short-term and long-term outcome compared to patients operated on for significant mitral valve regurgitation who have only minor or even no symptoms (NYHA class I/II). However, the compliance to undergo complex open-heart surgery via a median sternotomy in asymptomatic patients is very low. Minimally invasive endoscopic mitral valve repair may be an option to increase compliance in these patients, which will result in improved long-term survival with a normal life expectancy.
Cardiovascular Surgical Procedures↗
Mitral valve repair with aortic valve replacement in rheumatic heart disease.
From 1992 to 2001, 609 patients with rheumatic heart disease underwent aortic valve replacement with either mitral valve repair (n = 201) or mitral valve replacement (n = 408). Follow-up extended to 10 years. Thirty-day mortality was 1.4% for mitral valve repair and 0.7% for mitral valve replacement (p = 0.4). Survival at 9 years was 96.5 +/- 1.4% after mitral valve repair and 89.7 +/- 7.8% after mitral valve replacement (p = 0.73). Freedom from major bleeding at 9 years was 94.8 +/- 2.4% after mitral valve repair and 81 +/- 7.2% after mitral valve replacement (p = 0.03). Freedom from other valve-related complications and from mitral valve re-operation was similar for the two groups. This study showed that in patients with rheumatic heart disease the results of mitral valve repair with aortic valve replacement were comparable to those of double valve replacement. Major bleeding was less frequent after mitral valve repair with aortic valve replacement. Therefore, whenever feasible, mitral valve repair should be attempted in patients with rheumatic heart disease who need concomitant aortic valve replacement.
Aortic Valve↗
Effects of valve substitute on changes in left ventricular function and hypertrophy after aortic valve replacement.
BACKGROUND: Residual left ventricular hypertrophy adversely affects long-term outcome after aortic valve replacement. A stentless biological valve in the aortic position has been shown to offer a better hemodynamic profile than a stented one. However, it remains to be defined whether this difference is translated into inter-mediate-term effects on left ventricular structure and function. METHODS: One hundred thirty-seven patients receiving single aortic valve replacement (52 with concomitant coronary artery bypass graft) were enrolled in this study. Ninety-eight were men, and the mean age was 68 years (range, 55 to 90 years). Of the 137 patients, 39 had an aortic homograft, 72 a Toronto stentless porcine valve, and 26 had a stented porcine or bileaflet mechanical valve, with mean valve size of 25 +/- 2.5 mm (mean +/- standard deviation). Left ventricular muscle mass and function were assessed by M-mode echocardiography performed before and 0.5, 6, 12, 24, and 36 months after operation, and recorded on paper for off-line digitizing. Peak valve prosthesis pressure gradients were quantified by continuous wave Doppler. RESULTS: A total of 330 echocardiograms obtained during this study were adequate for computer digitizing. Clinical data, preoperative left ventricular function, and hypertrophy were similar between the three groups. Significant improvement in left ventricular function and major regression of left ventricular hypertrophy had occurred in the entire population by 6 months after operation. Multivariate analysis of variance showed that patients with previous aortic regurgitation had a larger left ventricular cavity size (p < 0.001) and greater mass index (p = 0.001) postoperatively than those with previous aortic stenosis. In addition, peak valvular gradient was lower (p < 0.001), mass index less (p < 0.001), and left ventricular function more normal both systolic, by a greater peak velocity of dimension shortening (p = 0.05) and wall thickening (p = 0.002), and diastolic, by a greater peak velocity of dimension lengthening (p = 0.046), with an aortic homograft or stentless porcine valve compared with a mechanical or stented biological valve. There was no significant difference in peak valve gradient, left ventricular mass index, or function between the aortic homograft and the stentless porcine valve. Age, sex, and concomitant coronary artery bypass graft, as well as aortic cross-clamp time, cardioplegia method, and valve size all proved to be insignificant determinants of postoperative left ventricular hypertrophy or function. CONCLUSIONS: In the first 2 years after implantation, the superior hemodynamic performance of aortic homograft and stentless porcine valve appears to result in more extensive regression of ventricular hypertrophy and greater improvement of left ventricular function than occurs with a mechanical or stented biological valve. These findings encourage the use of a stentless biological valve in older patients requiring aortic valve replacement, and a larger scale long-term randomized study of stentless versus stented biological valve or mechanical valve seems warranted.
Aged↗
Mitral valve repair versus mitral valve replacement.
Over the past 40 years mitral valve surgery has changed dramatically. After initial enthusiasm with the introduction of valve prostheses in the 1960s, a renewed interest in repair techniques began in the 1970s with the introduction of annuloplasty rings. These repair techniques revealed that the integrity of the subvalvular apparatus plays an important role in left ventricular function. When considering the major series comparing early and late results of mitral valve repair versus prosthetic mitral valve replacement, operative mortality rate is lower for patients with mitral valve repair. Long-term results also show a superior survival rate after mitral valve reconstruction. In addition, several problems can occur with the prosthetic valve, such as thromboembolism and endocarditis. All of these factors favor valve repair over replacement. The success of mitral valve repair depends on many factors: etiology of the mitral valve disease and the resultant pathomorphology of the valve, patient's circumstances such as age or contraindication for anticoagulation, and the experience of the surgeon. The decision whether to repair or replace the mitral valve depends on these factors. Data in the literature and in large collective databases reflect the advantages of mitral valve repair, with over 75% of current mitral valve surgeries being repairs. In the past 5 years the exposure of the mitral valve through a right lateral minithoracotomy using video assistance has developed into a widespread technique. This approach allows complex mitral valve repair as well as mitral valve replacement even with biological stentless prostheses, with decreased morbidity. The addition of radiofrequency ablation for restoration of sinus rhythm enhances the outcome after mitral valve surgery, and can also be easily performed through a minithoracotomy technique.
Follow-Up Studies↗
Fusion of valve cushions as a key factor in the formation of congenital bicuspid aortic valves in Syrian hamsters.
BACKGROUND: Bicuspid aortic valve is the most frequent congenital cardiac malformation in humans. However, the morphogenesis of the defect is still unknown. Previous work showed that, in the Syrian hamster, congenital bicuspid aortic valves with the aortic sinuses arranged in ventrodorsal orientation are expressions of a trait the variation of which takes the form of a continuous phenotypic spectrum, ranging from a tricuspid aortic valve with no fusion of the ventral commissure to a bicuspid aortic valve devoid of any raphe. The present study was designed to elucidate the mechanism involved in the formation of bicuspid aortic valves in Syrian hamsters as a possible starting point for further investigation of this process in humans. METHODS: The sample examined consisted of 80 embryos, aged between 10 days, 16 hours and 13 days, 1 hour postcoitum. Most (n = 59) of the embryos belonged to a laboratory-inbred family of Syrian hamsters with a high incidence of bicuspid aortic valves. The study was carried out using scanning electron microscopy and histological techniques for light microscopy. RESULTS: Twenty-three embryos showed a still undivided conotruncus. In all of these cases there were six mesenchymal semilunar valve primordia protruding into the lumen of the conotruncus. In a further 29 embryos, the conotruncus had just divided into the aortic and pulmonary channels; the embryos were at the beginning of the valvulogenesis. In 13 of these 29 embryos there were three well-defined aortic valve cushions, right, left, and dorsal, whereas in the other 16, the right and left valve cushions were more or less fused toward the lumen of the aorta; when they were completely fused, only two aortic valve cushions, a ventral and a dorsal, could be identified. In the remaining 28 embryos, the aortic valve cushions showed a marked degree of excavation. In 23 of these cases, the valve exhibited a basically tricuspid architecture, whereas it was unequivocally bicuspid in the other five. CONCLUSIONS: All variants of the aortic valve morphologic spectrum occurring in the Syrian hamster develop from three mesenchymal valve cushions, right, left, and dorsal, after normal septation of the conotruncus. The bicuspid condition of the aortic valve is not the consequence of improper development of the conotruncal ridges, conotruncal malseptation, valve cushion agenesis, or lesions acquired after a normal valvulogenesis. Fusion of the right and left valve cushions at the beginning of the valvulogenesis appears to be a key factor in the formation of bicuspid aortic valves. Each aortic valve acquires its specific morphology prior to the end of the valvulogenetic process.
Animals↗
Demographic characteristics of patients undergoing aortic valve replacement for stenosis: relation to valve morphology.
OBJECTIVE: To determine the relative importance of the different causes of isolated aortic valve stenosis in a surgical series, and to relate these to patient characteristics including the rate of insertion of bypass grafts for coronary artery disease. DESIGN: Survey of the clinical and pathological data on patients undergoing aortic valve replacement for isolated stenosis. SETTING: Tertiary care cardiothoracic surgical unit. PATIENTS AND METHODS: 465 adult patients undergoing aortic valve replacement representing a consecutive series in one surgical unit. Retrospective review of patients records and classification of cause of aortic stenosis based on pathological examination of excised valve cusps. RESULTS: 63.7% patients had calcific bicuspid valves, 26.9% tricuspid calcific valves, and 5.4% rheumatic, 2.6% mixed pathology and 1.5% unicommissural valves. The ratio of males to females for bicuspid valves was 1.85:1 and for tricuspid calcific valves 0.76:1. The mean age of patients with bicuspid valves was 64.9 years compared with 73.4 years for those with tricuspid valves. Some 22.3% of patients with bicuspid valves and 44.8% of those with tricuspid valves had sufficient coronary artery disease to necessitate insertion of coronary bypass grafts. The differential rate of insertion of coronary bypass grafts was independent of age. CONCLUSIONS: Bicuspid calcified aortic valves are the predominant cause of isolated aortic valve stenosis followed by tricuspid calcified aortic valves. The sex and age distribution of bicuspid and tricuspid calcific aortic valve stenosis is different. The higher rate of insertion of vascular grafts in tricuspid calcific aortic valves may indicate that risk factors for atherosclerosis enhance cusp calcification in these patients.
Adult↗
[Aortic valve replacement: technique and outcome with artificial heart valves and allografts].
Prosthetic aortic valve replacement has become a highly effective surgical treatment for aortic valve stenosis and aortic valve incompetence. After a properly timed aortic valve replacement, age- and gender-related actuarial survival can be similar to those of a normal healthy population, if serious late valve-related complications do not occur. The perioperative risk of isolated aortic valve replacement approaches 1% to 2% mainly influenced by valve- and patient-related factors such as age, left ventricular function, New York Heart Association class, preoperative hemodynamic and time of operation. Despite a number of various mechanical, bioprosthetic and biological heart valve prostheses, aortic valve replacement remains a palliative surgical treatment. Life-long anticoagulation is required by patients with mechanical heart valve prostheses, and, degeneration and subsequent reoperation is inherent in all bioprosthetic devices. The availability of cryopreserved allograft is limited and the Ross-operation is a technically demanding procedure with a somewhat higher perioperative mortality. Perioperative morbidity after isolated aortic valve replacement is low. A fatal neurological event, the most dreaded complication after aortic valve replacement, is found in about 0.5% of patients. Post-operatively, left ventricular hypertrophy decreases and cardiac dysfunction, reflected by the left-ventricular ejection rate is reversed in most patients, associated with an excellent clinical outcome and an age- and sex-specific normal long-term survival. To offer the most appropriate valve substitute to the individual patient, the debate focus on the question of whether patients benefit from durable mechanical heart valves or a primary anticoagulation-free bioprosthesis. However, there is no difference found between the prostheses types with regard to serious valve related complications such as major thromboembolism and hemorrhage, fatal reoperation and valve-related mortality. The search for an ideal permanent substitute for the aortic valve continues. To date, proper indication, optimal timing of the operation and careful analysis of the late results may help to improve the long-term survival of patients with after isolated aortic valve replacement.
Aortic Valve↗
[Comparative analysis of mechanical and biological prosthetic valves after isolated valve replacement--cooperative study on total 1281 patients].
A total of 1281 patients (594 aortic and 687 mitral) received 734 mechanical valves (320 Björk-Shiley, 283 SJM and 131 Omniscience) and 547 biological (259 ionescu-Shiley, 227 Hancock, and 61 Carpentier-Edwards) were analyzed for postoperative valve dysfunction and thromboembolism. The actuarial survival rates (free from late cardiac deaths and valve-related deaths) were 88.6% (11 years) for mechanical mitral and 86.0% (11 years) for biological mitral valves, and 91.7% (16 years) and 88.5% (12 years), for mechanical and biological aortic valves, respectively. There were no significant differences among these groups. Actuarial rates of freedom from valve-related events were 88.7% (11 years) and 51.7%, for mechanical and biological mitral valves, respectively. There was significant difference between the two types of valves in over 7 years after surgery. In contrast, there were no significant differences between mechanical and biological aortic valves. Actuarial rates of freedom from valve dysfunction were 97.6% (11 years) for mechanical and 56.5% (12 years) for biological mitral valves. The net 12 year results showed no significant differences between the two types of mitral prosthetic valves, but a significantly increased rate of valve dysfunction in the biological mitral valves compared with the mechanical in over 6 years of the study. Concerning AVR, there were no significant differences in the incidence of valve dysfunction between mechanical and biological aortic valves. Actuarial rates of freedom thromboembolism were 92.3% (11 years) and 93.8% (11 years) for mechanical and biological mitral valves, respectively. There were no significant differences between the two types of mitral prosthetic valves.(ABSTRACT TRUNCATED AT 250 WORDS)
Aortic Valve↗
Prosthetic valves or tissue valves--a vote for mechanical prostheses.
Thirty years of effort to obtain better substitutes for destroyed human heart valves brought continuous improvement of the various designs and materials used for the prostheses. However, none of the mechanical or tissue valves currently available meet all the requirements of an ideal artificial heart valve. Accurate comparison of results after implantation of mechanical and tissue valves is difficult because there are no randomized studies and most of the published results are gathered from patient groups operated on in different centers and over different time frames. Reliable comparison therefore presumes criteria to assess the success of valve replacement. The late outcome of heart valve replacement can be determined by subjective improvement, improvement of functional capacity and central hemodynamics, normalization of impaired ventricular function and by the frequency of complications related to or induced by the prostheses. Subjective improvement and improvement of functional capacity is obviously dependent on the degree of postoperative normalization of the hemodynamics. The hemodynamic properties of modern mechanical prostheses are superior to those of tissue valves because of the significantly more favourable relation between total prosthetic valve area and effective prosthetic valve orifice area, conditioned by design. These unfavourable hemodynamics are manifest especially when prostheses of smaller sizes are implanted. The main disadvantage of biological valves is their limited durability due to calcification with tissue damage resulting in degeneration and dysfunction. In addition to the risk of re-operation of tissue valves, for some patients hemodynamical deterioration with consecutive decrease of their functional capacity must be expected a considerable time before a second operation is mandatory. When compared with tissue valves, the most important disadvantage of mechanical valves is their thrombogenicity with the need for life-long anticoagulation therapy. However, the majority of patients with tissue valves do also require long-term anticoagulation because of factors allied by itself with an increased risk of thromboembolism. According to these advantages and disadvantages of mechanical and tissue valves, a differential therapy and an individualized approach should be preferred. Mechanical valves seem to be favourable in young patients, in patients with atrial fibrillation, high risk of reoperation or those in whom only small sized valves can be implanted.
Adult↗
The delta valve: how does its clinical performance compare with two other pressure differential valves without antisiphon control?
OBJECTIVE: The Delta valve is a pressure differential valve with a siphon control device. The valve mechanism is normally closed, but is designed to open in response to positive ventricular pressure, thereby avoiding overdrainage of cerebrospinal fluid (CSF). As a result, the incidence of subdural fluid collections as well as postural symptoms is purportedly reduced. In addition, the valve might reduce the number of obstructions as there would be no negative pressure sucking tissue and debris into the shunt system. In order to assess whether use of the Delta valve reduced the number of shunt-related problems as compared with two other pressure differential valves without an antisiphon component, we performed a retrospective review of all children undergoing CSF diversion procedures at our institution. METHODS: We reviewed the charts of 1, 193 patients. Cases included 2,325 ventriculoperitoneal (V-P) shunt insertions or revisions from January 1, 1985, to December 31, 1994, performed at our institution. The Delta valve and two pressure differential valves without antisiphon function were exclusively inserted during the following time periods: Holter-Hausner (H-H): January 1, 1985, to August, 1987; Heyer-Schulte (H-S): August, 1987, to June, 1991, and Delta: June, 1991, to December 31, 1994. RESULTS: Of the cases reviewed, 475 patients underwent insertion of a V-P shunt at the Childrens Hospital of Los Angeles and had a total of 686 shunt operations. Median follow-up was 3 years and ranged up to 10 years. Kaplan-Meier analysis documented that 67% of H-H, 71% of H-S and 70% of the Delta valves were functioning at 1-year follow-up. At 2-year follow-up, 66% of H-H, 64% of H-S and 65% of the Delta valves were functioning. The difference was not statistically significant. The occurrence rate for symptomatic subdural fluid collections was 0.7% (1/130) for H-H, 2.2% (3/139) for H-S and 1.0% (2/206) for the Delta valve (p = 0.52). The combined breakage/obstruction rate for the series was 7.7% (10/130) for H-H, 2.9% (4/139) for H-S and 4.9% (10/206) for the Delta valve (p = 0.19). No Delta valves malfunctioned secondary to fibrous capsule affecting the antisiphon device. CONCLUSIONS: In conclusion, it appears that performance of the Delta valve was not significantly different from the H-H and H-S valves, two valves without an antisiphon device. There was no significant difference in the occurrence of symptomatic subdural fluid collections based upon valve type, or in the combined valve breakage/obstruction rates based upon valve type.
Cerebrospinal Fluid Shunts↗
Prosthetic valve type for patients undergoing aortic valve replacement: a decision analysis.
BACKGROUND: In two large, randomized, clinical trials long-term survival after aortic valve replacement (AVR) was similar for patients receiving tissue and mechanical aortic heart valve prostheses. Higher bleeding rates among patients with mechanical valves, who must receive permanent oral anticoagulation to prevent thromboembolism, were offset by higher reoperation rates for valve degeneration among patients with tissue valves. Because the average age of patients undergoing AVR and clinical practices have changed considerably since the randomized clinical trials were conducted, we performed a decision analysis to reassess the optimal valve type for patients undergoing AVR. METHODS: We used a Markov state-transition model to simulate the occurrence of valve-related events and life expectancy for patients undergoing AVR. Probabilities of clinical events and mortality were derived from the randomized clinical trials and large follow-up studies. RESULTS: Although the two valve types were associated with similar life expectancy in 60-year-old patients (mean age of patients in the randomized clinical trials), tissue valves were associated with greater life expectancy than mechanical valves (10.7 versus 11.1 years) in 70-year-old patients (currently mean age of AVR patients). For 70-year-old patients, the effects of major bleeding complications (24%) with mechanical valves substantially outweighed those of reoperation for valve failure (12%) with tissue valves at 12 years. Of the clinical practice changes assessed, the recommended valve type was most sensitive to changes in bleeding rates with anticoagulation. However, bleeding rates would have to be 68% lower than those reported in the European randomized clinical trial to affect the recommended valve type for 70-year-old patients. Reoperation rates would have to be five times higher, and mortality rates at reoperation would have to be four times higher to affect the recommended valve type for 70-year-old patients. CONCLUSIONS: Although mechanical valves are preferred for AVR patients less than 60 years old, most patients currently undergoing AVR are elderly and would benefit more from tissue valves.
Aged↗
Leaflet movement of the ATS valve in the aortic position: unique behavior observed in 19-mm valves.
BACKGROUND: Leaflet opening angles of ATS valves in vivo tend to be less than those reported by the manufacturer, and there is a wide variation in opening angles even among valves of the same size. METHODS: Leaflet movement of aortic ATS valves was evaluated by cineradiography in 77 patients. The mean period from valve replacement to cineradiography was 40.2 months, and during that period, the ATS valve was replaced due to prosthetic valve obstruction in 1 of the 77 patients. RESULTS: In 76 patients with a normally functioning ATS valve, the mean opening angle of 19-mm valves (66.3 degrees +/- 2.3 degrees) was significantly less (p < 0.0001) than that of ATS valves 21 mm or larger (72.2 degrees +/- 3.8 degrees in 21-mm, 72.4 degrees +/- 2.8 degrees in 23-mm, and 72.8 degrees +/- 2.9 degrees in 25-mm valves). No significant differences were found in the opening angles of ATS valves 21 mm or larger, and the opening angles exceeded 65 degrees in all 69 patients with valves in this category. In one case of obstruction in a 21-mm valve, the opening angle was 57.5 degrees. The closing angle was 24.9 degrees +/- 1.3 degrees, which corresponded well with the manufacturer's in vitro data. CONCLUSIONS: The opening angle in the 19-mm ATS aortic valve is significantly less than that in valves 21 mm or larger, and an opening angle of less than 65 degrees probably indicates prosthetic valve obstruction in aortic ATS valves sized 21 mm or larger.
Adolescent↗
Assessment of mitral valve volume by quantitative three-dimensional echocardiography in patients with rheumatic mitral valve stenosis.
BACKGROUND: Thickening of mitral leaflets in rheumatic mitral valve stenosis is well described in necropsy studies; however, volume computation of the thickening mitral leaflets has not been attempted. 4trial fibrillation is one of the complications of rheumatic mitral stenosis. Quantitative assessment of thickened mitral valve and its relation to clinical complications is clinically desirable. HYPOTHESIS: The study was undertaken to compare measurement of mitral valve volume in normal subjects and in patients with rheumatic mitral valve stenosis. METHODS: An HP Sonos 2500 echocardiographic system with 5 MHz multiplane transesophageal transducer was used for data acquisition, and TomTec Echoscan computer setup was used to off-line volume computation. Study subjects included 10 normal subjects (mean age 44.8 years) and 36 patients with rheumatic mitral valve stenosis (22 female, 14 male) with an age range of 25 to 69 years (mean age 47 +/- 9.6 years). Mitral valve volumes were compared between the normal subjects and patients with mitral valve stenosis, and further comparison was made between the sinus rhythm (SR) and atrial fibrillation (AF) groups in patients with mitral valve stenosis. In all study subjects, the mitral valve area (MVA) was determined by two-dimensional echocardiography. RESULTS: Quantitative three-dimensional (3-D) echocardiography showed that mitral valve volume was significantly larger in patients with mitral valve stenosis than in normal subjects (9.0 +/- 2.2 and 4.5 +/- 0.7 ml, respectively, p < 0.001). When patients with mitral valve stenosis were divided into the SR and AF groups, mitral valve volume was found to be significantly larger in the AF group than in the SR group (9.76 +/- 2.2 ml. and 7.72 +/- 1.5 ml, respectively, p < 0.01) and patients in the AF group tended to be older (p < 0.05) with larger left atrial diameter (LAD) (p < 0.01). However, MVA between the two groups showed no statistical significance (1.1 +/- 0.43 and 1.0 +/- 0.34 cm2, respectively, p > 0.2). When the study subjects were divided into two groups (< 50 and > or = 50 years) according to age, the comparison of mitral valve volume between these two groups (9.37 +/- 2.18 and 8.56 +/- 2.14 ml, p > 0.2) showed no statistical significance. CONCLUSIONS: Quantitative 3-D echocardiography can be applied for the measurement of mitral valve volume in vivo. Patients with rheumatic mitral valve stenosis with atrial fibrillation have a propensity to have a larger mitral valve volume and are older than the patients with sinus rhythm; however, the age per se does not seem to be a cause for larger mitral valve volume.
Adult↗