PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “HEART VALVE PROSTHESIS”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 379 records · Page 21Linked to original sources

[Mitral stenosis].

The decrease in the incidence of acute rheumatic fever in western countries has led to a sharp decrease in the incidence of mitral stenosis. This decrease also modifies the clinical presentation and mitral stenosis is now encountered in older patients who have severe impairment of valve anatomy. In developing countries, mitral stenosis remains a frequent disease. The management of patients with mitral stenosis has been modified by the development of percutaneous mitral commissurotomy whose safety and efficacy have been demonstrated in a number of studies with a follow-up of up to ten years. Percutaneous mitral commissurotomy is now the reference treatment for mitral stenosis with pliable valves in young patients and its efficacy has been validated in randomised trials versus surgery. Mitral stenosis in older patients, as it is encountered in western countries, is a more heterogeneous group. Predictive analysis has shown that the predictions of immediate and late results are multifactorial. This has led to consider the indications for percutaneous mitral commissurotomy in patients who do not have ideal anatomic conditions, when their other characteristics are favourable. This is particularly the case in young patients who do not have a very tight mitral stenosis (1-1.5 cm2) and who do not have an advanced heart disease. When the conditions are favourable, percutaneous mitral commissurotomy can be considered in patients who have few symptoms, in particular in order to reduce the thromboembolic risk.

Age Factors↗

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↗

Rest and exercise performance of the Medtronic Advantage bileaflet valve in the aortic position.

BACKGROUND: The aim of the study was to evaluate rest and exercise performance and left ventricular mass regression of the Medtronic Advantage (Medtronic, Inc, Minneapolis, MN) prosthesis in the aortic position at 1 year at a single center as part of a multicenter, prospective clinical trial. METHODS: Between May 2002 and June 2003, 63 consecutive patients underwent aortic valve replacement with a Medtronic Advantage prosthesis (84.1% male; mean age, 56.0 +/- 9.7 years; ejection fraction, 56.5 +/- 15.8%). Valve lesions were stenosis (n = 20), mixed (n = 34), and insufficiency (n = 9). Concomitant procedures were performed in 34.9%. Follow-up was 100% complete. Echocardiographic data were obtained early postoperatively and at 1 year, combined with stress echocardiography by treadmill. Mean pressure gradients, stroke volume, and left ventricular mass were determined by echocardiography. Data are presented as mean +/- standard deviation. RESULTS: Operative mortality was 0%. Valve-related complications were observed in 2 patients (endocarditis, n = 1; thromboembolic event, n = 1). There was no case of antithromboembolic hemorrhage, prosthesis-related explant, or reoperation. One patient showed moderate paravalvular regurgitation. Mean pressure gradients 1 year postoperatively ranged from 6.3 to 11.0 mm Hg across all valve sizes. Left ventricular mass regression at 1 year was 18.4% across all valve sizes (p < 0.001). No severe patient-prosthesis mismatch (effective orifice area index < or = 0.65 cm2/m2) could be observed. CONCLUSIONS: After 1 year, the Medtronic Advantage valve shows comparable transvalvular mean pressure gradients across the valve sizes used during rest and exercise. This is accompanied by a significant left ventricular mass regression, an important indicator for long-term survival.

Adult↗

Bovine valved xenograft in pulmonary position: medium-term follow-up with excellent hemodynamics and freedom from calcification.

BACKGROUND: This study was designed to evaluate the outcome of Contegra xenograft valved conduit (Contegra, Medtronic Inc, Minneapolis, MN). METHODS: From April 1999 to December 2003, 67 patients with a mean age of 16.1 +/-15.0 years (2 months to 53 years) and a mean weight of 39.7 +/- 27.1 kg (4 to 95 kg) were discharged after implantation of a Contegra conduit. The diagnosis contained the following: pulmonary valve replacement during Ross operation (n = 27), pulmonary valve regurgitation (n = 9), tetralogy of Fallot (n = 7), pulmonary atresia with ventricular septal defect (n = 7), double outlet right ventricle (n = 7), truncus arteriosus (n = 5), Taussig-Bing (n = 2), obstructed conduit (n = 2), and double discordance (n = 1). Conduit size was 14 mm in 2, 16 mm in 7, 18 mm in 12, 20 mm in 13, and 22 mm in 33 patients. Mean cardiopulmonary bypass was 155 +/- 48 min (65 to 337 min) and mean aortic cross clamping was 69 +/- 38 min (0 to 146 min). All patients underwent echocardiography, 23 of 67 (34%) patients had cardiac catheterization, and 23 of 67 (34%) patients had electrocardiograph-gated multislice computer tomography. RESULTS: In a mean follow-up of 26.4 months (1 to 56 months) there was one late death (1 of 67 patients; 1.5% mortality) unrelated to the conduit. Five patients underwent reoperation; four were nonconduit-related and one was to replace a twisted conduit. Five patients underwent interventional cardiology; three were nonconduit-related and two were to stent a twisted or stenotic conduit. Echocardiography showed absent valve regurgitation in 30 of 67 (45%) patients, trivial in 21 of 67 (31%) patients, mild in 16 of 67 (24%) patients. The transconduit pressure gradient remained stable during follow-up, with peak pressure gradient 17 +/- 11 mm Hg and mean gradient 8 +/- 6 mm Hg. Internal diameters corresponded to 110% +/- 20% of the implanted diameter at level of proximal anastomosis, 112% +/- 18% at valve level, and 110% +/- 14% at distal anastomosis. Calcifications were not found, with the exception of a minimal (2.3 mm) parietal calcification. CONCLUSIONS: The Contegra valved conduit provided excellent morphology and hemodynamics, and freedom from calcification in a medium-term follow-up.

Adolescent↗

[Communication between the left ventricle and the right atrium in infectious endocarditis. Diagnosis using Doppler-echocardiography].

The diagnosis of a communication between the left ventricle and right atrium was made by transthoracic and transoesophageal echocardiography in a 67 year old man with a recurrence of a methicillin-resistant staphylococcus aureus infectious endocarditis complicating aortic valve replacement with a bioprosthesis seven weeks previously. This diagnosis was confirmed at surgery; the left ventricular-right atrial communication was closed by suturing its edges and a new aortic valve prosthesis was implanted. Unfortunately, the patient died 4 months later of myocardial dysfunction although the infectious endocarditis seemed to have been sterilised by antibiotic therapy. Doppler echocardiography, especially using the transoesophageal approach is the best diagnostic method for rare complications of infectious endocarditis, usually of the aortic valve, the prognosis of which is improved by early surgery and appropriate antibiotic therapy for the causal organisms.

Aged↗

Patient prosthesis mismatch is rare after aortic valve replacement: valve size may be irrelevant.

BACKGROUND: Although small valve size and patient-prosthesis mismatch are both considered to decrease long-term survival, little direct evidence exists to support this hypothesis. METHODS: To assess the prevalence of patient-prosthesis mismatch and the influence of small valve size on survival, we prospectively studied 1,129 consecutive patients undergoing aortic valve replacement between 1990 and 2000. Mean and peak gradients and indexed effective orifice area were measured by transthoracic echocardiography postoperatively (3 months to 10 years). Abnormal postoperative gradients were defined as those patients with mean or peak gradient above the 90th percentile (mean gradient > or = 21 or peak gradient > or = 38 mm Hg). Patient-prosthesis mismatch was defined as those patients with indexed effective orifice area below the 10th percentile (< 0.60 cm2/m2). RESULTS: A multivariable analysis identified internal diameter of the implanted valve as the only independent predictor of abnormal gradients postoperatively. However, there was no significant difference in actuarial survival between normal and abnormal gradient groups (7 years: 91.2% +/- 1.5% versus 95.0% +/- 2.2%; p = 0.48). Freedom from New York Heart Association class III or IV (7 years: 74.5% +/- 3.1% versus 74.6% +/- 6.2%; p = 0.66) and left ventricular mass index were not different between normal and abnormal gradient groups. Patients with and without patient-prosthesis mismatch were similar with respect to postoperative left ventricular mass index, 7-year survival (95.1% +/- 1.3% versus 94.7% +/- 3.0%; p = 0.54), and 7-year freedom from New York Heart Association class III or IV (79.3% +/- 6.6% versus 74.5% +/- 2.5%; p = 0.40). In patients with patient-prosthesis mismatch and abnormal gradients, the majority had prosthesis dysfunction owing to degeneration. CONCLUSIONS: Severe patient-prosthesis mismatch is rare after aortic valve replacement. Patient-prosthesis mismatch, abnormal gradient, and the size of valve implanted do not influence left ventricular mass index or intermediate-term survival.

Adult↗

Aortic valve replacement for aortic insufficiency: valve type as a determinant of systolic strain recovery.

BACKGROUND AND AIM: Left ventricular (LV) 3D systolic strain decreases in absolute value postoperatively and does not recover in patients who undergo aortic valve replacement (AVR) for chronic aortic insufficiency (AI). We investigated whether choice of valve prosthesis (mechanical [St. Jude], bioprosthetic [bovine pericardial], Ross procedure) had a significant impact on strain recovery in this surgical population. METHODS: MRI with tissue-tagging was performed on 14 patients with chronic AI both before and 28 +/- 13 months after AVR. Average values of LV systolic strain and end-systolic stress (ESS) were computed from MRI data for the LV. Three types of prosthetic valve were examined (Ross procedure n = 4, bovine pericardial n = 5, and St. Jude n = 5). RESULTS: Overall, systolic strain, ESS, LV volumes, ejection fraction, and LV mass all changed significantly following AVR. Comparisons between individual valve types revealed no differences in any of these measurements. Patients who received a mechanical valve had a greater decrease in the absolute value of systolic strain following surgery compared to patients from the nonmechanical group (Ross procedure and bioprosthetic valve). Comparisons between the Ross group and the prosthetic group (St. Jude and bioprosthetic) produced no significant differences in strain, ESS, LV volume, and mass. CONCLUSIONS: These early results suggest that valve prosthetic type may be a factor in efforts to improve strain recovery after AVR for AI, although further investigation is warranted. MRI with tissue-tagging may be a useful tool for comparing the impact of prosthetic valve choice on incompletely recovered systolic strain following AVR for chronic AI.

Adult↗

Performance of 21-mm size perimount aortic bioprosthesis in the elderly.

BACKGROUND: Aortic valve replacement in elderly patients with a small aortic annulus may pose difficult problems in terms of prosthesis selection. We have evaluated the hemodynamic performance of the 21-mm Carpentier-Edwards Perimount bioprosthesis implanted in elderly patients. METHODS: From July 1996 to June 1998, 19 patients (17 women and 2 men, mean age 76+/-4 years and mean body surface area 1.73+/-0.13 m2), had aortic valve replacement with a 21-mm Carpentier-Edwards Perimount bioprosthesis. The hemodynamic performance of the valve was evaluated in 16 patients, who completed at least a 6-month follow-up interval, with transthoracic color-Doppler echocardiography with particular reference to peak and mean transprosthetic gradients, effective orifice area index, and regression of left ventricular mass index. RESULTS: There were no late deaths and no major postoperative complications. At a mean follow-up of 12+/-7 months, compared to discharge, all patients showed clinical improvement with a significant reduction of peak gradient (from 23+/-4 to 21+/-6 mm Hg, p = 0.04) and left ventricular mass index (from 181+/-23 to 153+/-20 g/m2; p<0.001), whereas mean gradient (from 13+/-3 to 13+/-4 mm Hg, p = not significant) and effective orifice area index (from 1.12+/-0.34 to 1.13+/-0.28 cm2/m2, p = not significant) remained substantially unchanged. CONCLUSIONS: The use of a 21-mm Carpentier-Edwards Perimount bioprosthesis is associated with low transprosthetic gradients and significant reduction in left ventricular hypertrophy after aortic valve replacement. The results of our study suggest that a 21-m Carpentier-Edwards Perimount bioprosthesis should be considered a valid option in elderly patients with aortic valve disease and a small aortic annulus.

Aged↗

Consideration of prosthesis-patient mismatch and left ventricular mass regression after implantation of the Carpentier-Edwards pericardial valve in elderly Japanese patients: body surface area may be irrelevant.

The assessment of prosthesis patient mismatch (PPM) for small aortic annulus is important for prognosis after aortic valve replacement (AVR). Recent investigations have demonstrated that PPM occurs in AVR patients with an indexed effective orifice area (iEOA) of less than 0.85 cm2/m2. We investigated hemodynamic performance and left ventricular mass (LVM) regression after AVR. Eighteen patients who underwent AVR using a 19-mm Carpentier-Edwards pericardial (CEP) valve without annular enlargement were studied by echocardiography and Doppler examination 4 months after AVR. Patients were divided into two groups on the basis of their body surface area (BSA); the smaller BSA (group S, 1.14-1.36 m2, nine patients) and the larger BSA (group L, 1.40-1.83 m2, nine patients). Of these 18 patients, ten underwent isolated AVR, and five underwent AVR with coronary artery bypass graft; (i.e., double valvular replacement, AVR with maze procedure, and AVR with mitral valvulophasty. There were no statistically significant differences between the two groups, except for age (group S, 78.3+/-2.5 years; group L, 73.6+/-2.4 years). There was no significant difference for the iEOA during the late phase at rest (group S, 1.10+/-0.26 cm2; group L, 1.02+/-0.28 cm2). However, there was a significant difference for the LVM regression between the preoperative and postoperative values (group S, 243+/-23.6 mg/cm2 [pre], 190+/-16.9 mg/cm2 [post]; group L, 302+/-13.7 mg/cm2 [pre], 199+/-16.7 mg/cm2 [post]). In elderly Japanese patients with a BSA of less than 18 m2, we demonstrated LVM regression and avoidance of PPM after implantation of the aortic 19-mm CEP valve.

Aged↗

Pannus formation in aortic valve prostheses in the late postoperative period.

We present three patients who underwent repeat aortic valve replacement for prosthetic valve dysfunction caused by tissue ingrowth in the late postoperative period. These patients (three women aged 48-51 years, mean 49.3 +/- 1.53 years) underwent operations for restriction of prosthetic valve leaflet movement by pannus in the left ventricular outflow tract. The interval from the previous operation ranged from 8.0 to 9.6 years (mean 9.6 +/- 2.0 years). The symptoms of the patients were New York Heart Association functional class I, II, and IV in one patient each. Diagnosis was made by cinefluoroscopy in two patients and aortography in one patient. The operative procedures consisted of aortic valve replacement ( n = 1) and aortic valve replacement with mitral valve replacement ( n = 2). Pannus was found at the left ventricular aspect of the prosthetic valve in all patients. In two patients, the pannus directly restricted movement of the leaflet and also severely narrowed the inflow orifice of the prosthetic valve. In the other patient, the pannus had grown at a distance of 7 mm from the valve and narrowed the left ventricular outflow tract circularly. The postoperative course was uneventful and all three patients were discharged in a good condition. One patient died of pneumonia 8 months after surgery and the other two patients have remained well and have been followed up for one and a half years. In conclusion, there may be a discrepancy between the clinical symptoms and the grade of subvalvular stenosis caused by pannus. Therefore, it is essential for satisfactory operative results that early diagnosis be made by various means.

Constriction, Pathologic↗

Transapical aortic valve implantation: an animal feasibility study.

BACKGROUND: Percutaneous aortic valve implantation has recently been performed in nonsurgical patients with severe aortic stenosis. Retrograde valve delivery has been problematic because of the size of the delivery system and concomitant peripheral vascular disease. We investigated a minimally invasive approach through the left ventricular apex for antegrade placement of a device-deliverable valve. METHODS: Transapical aortic valve implantation was performed using a 23-mm equine valve mounted on a stainless steel stent in 24 swine (weight range, 35 to 45 kg). A limited or full sternotomy approach was used to access the apex of the heart. The crimped valve was introduced through a sheath in the left ventricular apex. Fluoroscopy and echocardiography were used for guidance. Deployments were performed on the beating heart either with ventricular unloading using femoral extracorporeal circulation or rapid ventricular pacing. RESULTS: All valves were successfully delivered at the selected target site with acceptable visualization of the noncalcified aortic annulus. Valve migration occurred during eight deployments (two distal and six retrograde) secondary to persistent cardiac output, unfavorable annular anatomy, and dislodgement by the delivery catheter. Exact positioning of the nonmigrated valves at the aortic annulus was examined by necropsy of all animals at the end of the procedures. Paravalvular leak was noted in 14 of 18 (77.8%) valves remaining in situ. CONCLUSIONS: The transapical approach was used for the successful antegrade placement of a stented valve, obviating the technical problems associated with a large delivery system transiting the peripheral vascular system. Stent design contributing to paravalvular leak remains problematic.

Animals↗

Endoscopic off-pump aortic valve replacement: does the pericardial cuff improve the sutureless closure of left ventricular access?

OBJECTIVE: Off-pump trans left ventricular approach provides more precise deployment of stented aortic valve of any size with respect to the endovascular replacement. One of the key steps of this procedure is the ventricle repair after catheter withdrawing. We designed an animal study to compare the consistency of a sutureless repair of the left ventricle access using nitinol occluder with and without pericardial cuff on the ventricular side. METHODS: Material description: The Amplatz-nitinol occluder consists of two square heads squeezing ventricle wall in between them, sealing the defect. To improve its sealing property, a pericardial patch was sutured to the ventricular head of the occluder. Animal study setup: In adult pigs, a 30F sheath was inserted into the epigastric area through the cardiac apex, up to the left ventricle, simulating the approach for off-pump aortic valve replacement. The sheath was then removed and the ventricle closed with standard occluder in half of the animals, and cuffed occluder in the other half. Animals were followed-up for 3h, collecting haemodynamics data and pericardial bleeding. RESULTS: Device was successfully deployed in 12 animals in less than 1min. In the group where the standard occluder was used, bleeding during the deployment was 80+/-20ml and after the deployment was 800+/-20ml over 3h. In the group where the cuffed occluder was used, bleeding during the deployment was 85+/-20ml and after the deployment was 100+/-5ml over 3h. In the cuffed group, bleeding was significantly lower than the standard group, p-value being <0.001. CONCLUSIONS: The occluder is easy to use and the pericardial cuff dramatically increases its efficacy as demonstrated by a significant reduction of blood loss. The cuffed occluder opens the way for endoscopic, off-pump, transventricular aortic valve replacement.

Animals↗

Management of aortic insufficiency with continuous flow left ventricular assist devices: bioprosthetic valve replacement.

There are several methods for surgical management of aortic insufficiency in patients with end-stage congestive heart failure who are undergoing implantation of a left ventricular assist device (LVAD). To date, little is known about the long-term outcome of bioprosthetic valves for aortic insufficiency in patients with continuous flow LVADs. We report on two patients with bioprosthetic aortic valve replacement for aortic insufficiency at the time of HeartMate II LVAD insertion.

Aged↗

Mass regression in aortic stenosis after valve replacement with small size pericardial bioprosthesis.

BACKGROUND: The aim of the study was to determine whether left ventricular mass regression is influenced by valve size after the implantation of a Carpentier-Edwards Perimount (CEP) pericardial bioprosthesis for pure aortic stenosis. METHODS: Patients receiving 19-mm, 21-mm, and 23-mm CEP aortic valves underwent echocardiography preoperatively and at least 1 year after surgery (mean, 2.3 +/- 1 years) and the echocardiograms were compared within and between groups. RESULTS: The study involved a total of 88 patients: 34 receiving 19-mm CEPs, 29 receiving 21-mm CEPs, and 25 receiving 23-mm CEPs. The mean postoperative prosthetic gradients were respectively 20.6 +/- 6.6 mm Hg, 17.9 +/- 5.8 mm Hg, and 13.2 +/- 4.1 mm Hg (p = 0.0001); the mean postoperative valve areas were respectively 1.24 +/- 0.16 cm(2), 1.45 +/- 0.2 cm(2), and 1.63 +/- 0.21 cm(2) (p = 0.0001). In comparison with the preoperative echocardiographic measurements absolute left ventricular mass significantly decreased by -54.1 +/- 48.8 g, -54.1 +/- 55.1 g, and -74.4 +/- 57.4 g respectively with no statistically significant between-group difference (analysis of variance) but ventricular septum and posterior wall thickness significantly decreased in each group (p < 0.05). CONCLUSIONS: The implantation of 19-mm, 21-mm, and 23-mm CEP aortic prostheses significantly reduces left ventricular mass without any size-related differences.

Aortic Valve Stenosis↗

MRI-radiofrequency tissue tagging in patients with aortic insufficiency before and after operation.

BACKGROUND: Magnetic resonance imaging tissue tagging is a relatively recent methodology that describes ventricular systolic function in terms of intramyocardial ventricular deformation. Because the analysis involves the use of many intramyocardial points to describe systolic deformation, it is theoretically more sensitive at describing subtle differences in regional myocardial fiber shortening when compared with conventional measures of ventricular function such as wall thickening. The objectives of this study were (1) to define sensitive indices of ventricular systolic deformation to assist the clinician in the surgical evaluation of patients with aortic insufficiency, and (2) to quantify differences in regional systolic deformation before and after surgery for aortic insufficiency. METHODS: Magnetic resonance imaging with tissue tagging was performed on 10 normal volunteers and 8 patients with chronic severe aortic insufficiency. Follow-up postoperative studies (5.4+/-1.1 months) were obtained in 6 patients who underwent Ross procedure (1 patient), David procedure (1), and St. Jude aortic valve replacement (4). RESULTS: There was no significant difference in fractional area change, overall circumferential shortening, or overall radial thickening among the normal group, the preoperative aortic insufficiency group, or the postoperative aortic insufficiency group. However, on a regional basis, there was a decrease in posterior wall circumferential strains in the postoperative aortic insufficiency group (29%+/-13% preoperative aortic insufficiency (n=6) versus 24%+/-12% postoperative aortic insufficiency (n=6), p=0.02). CONCLUSIONS: On regional analysis, there was a small but significant decrease in posterior wall circumferential shortening after operation. Magnetic resonance imaging tissue tagging is a sensitive and clinically applicable method of quantifying regional ventricular wall function before and after intervention for aortic insufficiency.

Adult↗

Left ventricular mass reduction after aortic valve replacement: homografts, stentless and stented valves.

BACKGROUND: We studied the effect of four different types of prosthetic aortic valves on time course and extent of regression of left ventricular hypertrophy after aortic valve replacement for aortic stenosis. METHODS: Four groups of 10 patients each were randomly assigned to receive: (1) aortic homograft preserved in antibiotic solution at 4 degrees C, (2) Toronto stentless porcine valve, (3) Medtronic Freestyle stentless valve, or (4) Medtronic Intact aortic valve. The left ventricular mass index, effective orifice area index, and peak and mean transaortic gradients were measured by Doppler echocardiography before the operation and 8 months postoperatively. RESULTS: The hemodynamic performance indices were much better for the homograft and stentless valves than for the stented one. The absolute left ventricular mass index reduction was greater in the homograft group compared with the Intact (p = 0.0004) and Toronto (p = 0.007) groups. The extent of percent left ventricular mass index reduction was greater only in the homograft group versus Intact group (p = 0.005). The multilinear regression analysis showed that the only predictors of a larger percentage of left ventricular mass index reduction were the homograft type, a higher valve size index, and a higher preoperative left ventricular mass index. CONCLUSIONS: When a stentless or homograft aortic valve was used instead of a stented valve to replace a stenotic aortic valve there was more complete or at least faster regression of left ventricular hypertrophy. The hemodynamic performance of stentless porcine valves was similar to that of aortic homografts, nevertheless the aortic homografts preserved in antibiotic solution offered a faster regression of left ventricular hypertrophy during the same period of time.

Aged↗