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PubMed1989

[Results of heart valve replacement: especially on the selection criteria for valve prostheses and on a new anticoagulation regimen].

Since March 1981 till the end of 1987, a total of 76 artificial heart valves were implanted in 72 patients. Heart valve prostheses were selected individually according to the patient's needs rather than assigning a single model to every patient. Postoperatively patients were placed on an anticoagulation therapy regimen consisting of reduced-dose warfarin (prothrombin time maintained at 30% of the control) and a small dose (81 mg/day) aspirin. During this period no bioprosthesis was implanted. For aortic valves, Starr-Edwards caged-ball valves were used in 53.1% and St. Jude Medical (SJM) valves in 37.5%. For mitral valves, SJM valves were used in 68%. No mechanical valve failure and no thrombosed valve was encountered. There was one patient-prosthesis missmatch. The incidence of thromboembolism for the entire series was 5/181.2 patient-years. There was 1-2/181.2 patient-years incidence of hemorrhagic complications. These figures were comparable to the ones with conventional warfarin therapy. No intracranial hemorrhage was encountered. Our selection criteria for artificial heart valves and our method of anticoagulation were discussed in detail. We conclude that at present there is no single prosthesis which satisfies all the varying needs of every patient, and the prosthesis which is best suited to that particular patient should be selected. We are generally happy with our current method of postoperative anticoagulation and will continue with this regimen.

Adult↗
PubMed2005

Midterm results of Manouguian double valve replacement: comparison with standard double valve replacement.

OBJECTIVE: Surgical strategies for patients who have a small aortic annulus associated with a small mitral annulus remain controversial. The objective of this study was to assess the validity of the Manouguian procedure for double valve replacement with patch enlargement of the annuli. METHODS: We reviewed 57 consecutive patients who underwent double valve replacement for combined aortic and mitral disease between September 1991 and October 2000. Thirty patients underwent the Manouguian procedure with patch enlargement of the aortic and mitral annuli, and the other 27 patients had standard double valve replacement. The Manouguian procedure was selected for a small aortic annulus of less than 21 mm in diameter. The patients were followed for a median of 7.5 years. Results of echocardiography and the dobutamine stress test were compared postoperatively. RESULTS: Double valve replacement with the Manouguian procedure did not increase the early or midterm mortality because the survival (including operative death) at 8 years was 83% in the Manouguian group and 84% in the double valve replacement group (P = .82). The event-free rate at 8 years was 79% in the Manouguian group and 84% in the double valve replacement group (P = .6). The prostheses implanted at the aortic and mitral positions were smaller in the Manouguian group, even after annular enlargement. However, the transprosthetic gradient across the aortic valve evaluated by means of dobutamine stress echocardiography did not differ between the 2 groups, possibly because of a smaller body surface area in the Manouguian group. CONCLUSIONS: The Manouguian patch enlargement procedure is useful during double valve replacement when associated with the problem of small-valve annuli.

Adult↗
PubMed1985

Primary (spontaneous) chordal rupture: relation to myxomatous valve disease and mitral valve prolapse.

The excised valves of 152 consecutive patients who underwent isolated primary mitral valve replacement between May 1979 and July 1983 were studied to determine the cause of primary (spontaneous) rupture of the chordae tendineae and estimate the prevalence of floppy mitral valve with underlying myxomatous disease. Of these 152 patients, 72 had nonrheumatic disease; 42 (28% of the total group) had a floppy valve, and 39 of these valves had microscopic changes of myxomatous disease. Primary chordal rupture had occurred in 31 patients, including 29 with myxomatous disease. Seven of these patients had prior documentation of mitral valve prolapse and an additional 20 patients had a long-standing murmur. Ischemic mitral regurgitation (22 patients) accounted for the majority of the remaining 30 patients with nonrheumatic disease. Therefore, approximately half of all isolated mitral valve replacements in this institution are now performed for nonrheumatic disease, the majority for a floppy valve in which myxomatous disease was the underlying abnormality. Primary chordal rupture almost invariably occurs as a complication of myxomatous disease, and mitral valve prolapse may be a common precursor.

Adult↗
PubMed2002

Optimal size of prostheses for functioning of the aortic prosthetic valve in aortic and mitral valve replacement with annular enlargement through Manouguian's technique.

There is not yet agreement about the optimal size of the prostheses in aortic and mitral valve replacement with Manouguian's technique. In this technique, the aortic prosthetic valve can be pushed upon the mitral prosthesis which may cause dysfunction of the aortic prosthetic valve. The aim of this study was to clarify the size of the prostheses needed to avoid dysfunction of the aortic prosthetic valve. Three patients underwent aortic and mitral valve replacement through this procedure. Two of them had active aortic and mitral valve endocarditis. Aortomitral continuity involved with abscesses could be approached and completely excised using this technique. All patients survived the operation, but 1 of them suffered aortic mechanical valve dysfunction for the reason stated. Anatomical analysis of the geometrical relation of the 2 prosthetic valves suggests that the mitral annulus should be enlarged less than 25 mm to avoid dysfunction of the aortic prosthetic valve.

Adult↗
PubMed2001

Fate of mild aortic valve disease after mitral valve intervention.

OBJECTIVE: This study was performed to assess the long-term outcome of untreated mild aortic valve disease present at the time of initial mitral valve intervention. METHODS: A total of 284 patients with rheumatic heart disease aged 7 to 62 years (mean, 23.5 +/- 12.2 years) who underwent mitral valve intervention and had mild aortic valve disease initially were followed up for 2 to 18 years (mean, 10.8 +/- 3.7 years). At initial intervention, 232 patients had pure mild aortic regurgitation, and 52 patients had mild aortic stenosis with or without aortic regurgitation. RESULTS: Among patients with mild aortic regurgitation initially, 11 (5%) patients progressed to moderate (n = 6) or severe (n = 5) regurgitation over an interval of 9 to 17 years (mean, 12.1 +/- 2.8 years), and 1 patient had moderate aortic stenosis and severe aortic regurgitation after 10 years. Freedom from development of moderate-severe aortic valve disease in patients who initially had mild aortic regurgitation was 100%, 97.0% +/- 1.7%, and 87.4% +/- 4.6% at 5, 10, and 15 years, respectively. Seventeen (35%) patients with initial mild aortic stenosis (with or without regurgitation) had moderate or severe stenosis (with or without moderate-severe regurgitation) after an interval of 4.9 +/- 3.8 years. Freedom from development of moderate-severe aortic valve disease in patients who initially had mild aortic stenosis was 75.6% +/- 6.2%, 61.5% +/- 8.5%, and 46.1% +/- 11.2% at 5, 10, and 15 years, respectively. Ten patients required aortic valve replacement for aortic valve dysfunction. CONCLUSIONS: Mild aortic regurgitation present at the time of mitral valve intervention progresses very slowly and less frequently requires reintervention. However, mild aortic stenosis diagnosed initially progresses more often and more rapidly and thus needs closer follow-up.

Adolescent↗
PubMed1994

Valve transplantation to the canine popliteal vein: the utility of a distal arteriovenous fistula and the hemodynamic result of a single functional valve.

PURPOSE: The objectives were to transplant a venous valve into the popliteal vein of a canine insufficiency model that would maintain long-term function and then to measure the hemodynamic benefit of such a valve. METHODS: Indexes of venous valvular function, including venous filling time, 90% of venous refilling time, and simulated ambulatory venous pressure, were measured in 11 greyhounds before intervention (Control) and after hind limb venous valvulotomy, which produces chronic venous insufficiency. Three weeks later a valve-containing segment of external jugular vein was transplanted to the popliteal vein with (n = 6) or without (n = 5) a distal arteriovenous fistula. The fistula was ligated in 4 to 6 weeks. Repeat venous indexes were obtained an average of 2 weeks after the last operative intervention. Gross anatomic inspection +/- duplex scanning performed before the animals were killed were used to distinguished normal from damaged valves. RESULTS: Four of five simple valve transplants demonstrated scarring and/or thrombosis and the average venous filling time, ambulatory venous pressure, and 90% of venous refilling time were consistent with chronic venous insufficiency and/or obstruction. One fistula failed in the six valve distal arteriovenous fistula transplants, and that valve was incompetent. Analysis of the remaining five functional valves demonstrated venous filling time consistent with chronic venous insufficiency, normalization of ambulatory venous pressure, and 90% of venous refilling time between normal, and chronic venous insufficiency. These valves appeared normal. CONCLUSIONS: Popliteal vein valve transplant anatomy is preserved by an adjunctive distal arteriovenous fistula, and a competent valve transplant improves postexercise venous hemodynamics to approach those of a normal limb.

Analysis of Variance↗
PubMed2002

Comparison of the Ahmed Glaucoma Valve, the Krupin Eye Valve with Disk, and the double-plate Molteno implant.

OBJECTIVE: To compare the efficacy of the nonvalved double-plate Molteno implant with two valved implants, the Krupin Eye Valve with Disc and the Ahmed Glaucoma Valve, in the treatment of recalcitrant glaucoma. PATIENTS AND METHODS: The authors performed a nonrandomized retrospective review of patients who received the Molteno implant (n = 27), Krupin Eye Valve with Disc (n = 13), or Ahmed Glaucoma Valve (n = 13), with adjunctive mitomycin C. RESULTS: Kaplan-Meier life-table analysis showed that the Molteno implant patients were more likely to maintain an intraocular pressure between 5 and 15 mm Hg than Ahmed Glaucoma Valve patients (P = 0.03). Success rates at 1 year were 80% (95% CI, 66-97%) for the Molteno implant, 39% (19-77%) for the Krupin Eye Valve with Disc, and 35% (15-82%) for the Ahmed Glaucoma Valve. However, Ahmed Glaucoma Valve patients were less likely to experience complications requiring reoperation or loss of two or more lines of visual acuity (P < 0.01) than Molteno implant or Krupin Eye Valve with Disc patients. CONCLUSIONS: This nonrandomized study suggests that the Molteno implant with mitomycin C is more likely to result in intraocular pressures in the lower teens than the Ahmed Glaucoma Valve with mitomycin C. The findings suggest that the Ahmed implant is less likely to create problems leading to reoperations or visual acuity loss than the Molteno or Krupin implants.

Adult↗
PubMed1976

Systemic atrioventricular valve regurgitation in corrected transpositon of the great vessels. Angiographic differentiation of operable and nonoperable valve deformities.

Abnormalities of the systemic atrioventricular (A-V) valve are frequently present in patients with corrected transposition. Systemic A-V valve regurgitation is usually present and may be amenable to operative correction with valve replacement if the regurgitation is caused by normally positioned but deformed valve leaflets or a dilated valve ring, or both. Systemic A-V valve regurgitation secondary to the more common Ebstein-type malformation of the inverted tricuspid valve is an inoperable conditon at present. Displacement of the valve leaflets below the level of the valve ring may be seen in the angiocardiograms of patients with this finding and is the differentiating feature between the two lesions. Ten cases of systemic A-V valve regurgitation in patients with corrected transposition are reviewed to illustrate these features.

Adolescent↗
PubMed2005

Atrioventricular valve procedures with repeat fontan operations: influence of valve pathology, ventricular function, and arrhythmias on outcome.

BACKGROUND: The purpose of this study is to analyze atrioventricular valve procedures when performed in association with repeat Fontan operations and to determine the influence of atrioventricular valvar pathology, ventricular function, and arrhythmias on outcome. METHODS: Between December 1994 and August 2004, 80 patients had repeat Fontan operations that included arrhythmia surgery (78 of 80), venous pathway revision (78 of 80), atrioventricular valve repair-replacement (15 of 80), and other associated procedures. Mean ages were the following: at operation, 20.3 +/- 8.4 years; at prior Fontan, 7.1 +/- 5.8 years. Atrioventricular valve procedures were performed on 8 functionally mitral and 7 functionally tricuspid valves. The average cross-clamp and cardiopulmonary bypass times were 61.9 +/- 42.8 minutes and 218 +/- 82 minutes, respectively. RESULTS: Ventricular dysfunction (8% vs 54%, p < 0.0001), valvar dysfunction (13% vs 25%, p < 0.05), and atrial arrhythmias (18% vs 86%, p < 0.0001) increased during the preceding 12.0 +/- 4.7 years before the most recent Fontan operation. Multivariate analysis for death, orthotopic cardiac transplantation (OCT), or renal dialysis showed severe ventricular dysfunction, age greater than 25 years, right or ambiguous functional ventricle, and ischemic time greater than 100 minutes to be highly significant. Notably, cardiac index, elevated end diastolic pressure, and atrial fibrillation were not predictors of outcome. Mitral valve repairs were inconsistent due to probable technical misjudgments; most tricuspid valves could not be repaired. Operative and late mortality were 1.2% and 5.0%, respectively. Emergent and late OCT were 1.2% and 3.7%, respectively. CONCLUSIONS: Risk factors for poor outcome are severe ventricular dysfunction, right or ambiguous single ventricle, age greater than 25 years, and ischemic time greater than 100 minutes. Mitral valves are potentially more amenable to repair than are tricuspid valves. Prosthetic valve replacement should be considered when valve repair is questionable.

Adolescent↗
PubMed2005

In vitro evaluation of aortic valve prosthesis in a novel valved conduit with pseudosinuses of Valsalva.

OBJECTIVE: This study was undertaken to determine whether the presence of vortices immediately above a prosthetic aortic valve could negatively influence the in vitro hydrodynamic performances of a biologic or mechanical valve implanted in a new Dacron polyester fabric conduit that incorporates sculpted sinuses of Valsalva. METHODS: With a computer-controlled pulse duplicator, the in vitro performance (pressure differences, closure and leakage volumes, and energy losses) of a 25-mm mechanical or biologic prosthesis implanted in a standard Dacron straight conduit or in the new Dacron graft with a sculpted sinus were analyzed and compared. RESULTS: The mechanical and biologic prostheses at 7 L/min cardiac output showed pressure drops across the valve of 8.72 mm Hg and 13.45 mm Hg, respectively, when inserted in the new Valsalva-style graft and of 7.97 mm Hg and 12.94 mm Hg, respectively, when inserted in the standard graft. The closure and leakage volumes for mechanical valves were higher than those for biologic valves; however, the presence or absence of sinuses did not result in significant differences in closure and leakage volumes. The maximal total energy losses were 5.89% and 9.49% for mechanical and biologic valves, respectively. No differences were evident between the two different Dacron grafts for each prosthetic heart valve. CONCLUSION: The normal opening and closing behavior of a prosthetic aortic valve was not altered or modified by a different root shape above the heart valve. The presence of vortices inside the pseudosinuses of Valsalva did not influence the hydrodynamic properties of the biologic and mechanical valves tested.

Aortic Valve↗
PubMed2000

von Willebrand factor, fibrinogen, and soluble P-selectin levels after mitral valve replacement versus mitral valve repair.

Patients with mitral valve disease undergoing surgery are at an increased risk of thromboembolism. We hypothesized that this may be due in part to abnormalities in platelet activation, endothelial damage or dysfunction, and plasma fibrinogen in such patients. To test this hypothesis, we measured indexes of platelet activation (soluble P-selectin), endothelial damage or dysfunction (von Willebrand factor [vWf], enzyme-linked immunosorbent assay) and fibrinogen (modified Clauss) in 56 consecutive patients (35 women, mean age 65 years) admitted for isolated mitral valve repair (n = 39) or replacement (using mechanical implants, n = 17). Samples were taken from a peripheral vein before and at 3 months after valve surgery. Baseline results were compared with 56 healthy age- and sex-matched controls. Compared with controls, patients with mitral valve disease had higher levels of vWf (mean +/- SD 132 +/- 28 vs 101 +/- 35 IU/dl; p <0.001), but there were no significant differences in mean fibrinogen (p = 0.418) or soluble P-selectin (p = 0.855) levels between cases and controls. There was a significant increase in plasma vWf after mitral valve replacement: 142 +/- 25 IU/dl preoperatively, increasing to 161 +/- 33 IU/dl at 3 months after surgery (p = 0.0261). However, there were no significant changes in plasma fibrinogen (p = 0.306) or soluble P-selectin levels (p = 0.191). Patients undergoing mitral valve repair did not have any significant changes in mean vWf (p = 0.25), soluble P-selectin (p = 0.77), or fibrinogen (p = 0.22). There was a significant negative correlation (Spearman, r = -0.4, p = 0.003) in postoperative plasma vWf levels and the size of valve prosthesis used. Thus, patients with mitral valve disease have increased plasma vWf levels when compared with healthy controls, suggesting endothelial damage or dysfunction, with a further increase in levels after mitral valve replacement. Conversely, patients undergoing mitral valve repair do not demonstrate any significant changes in fibrinogen, or indexes of endothelial dysfunction or platelet activation.

Aged↗
PubMed1989

Allograft aortic valve implantation: techniques for all types of aortic valve and root pathology.

The geometry and degree of symmetry of the diseased aortic root and valve dictate the technical method of implantation of the allograft aortic valve. Five methods are available that are suitable for the full range of aortic root disease: the small aortic root with a valve annulus diameter less than 21 mm, the common aortic valve lesions (valve annulus diameter, 21 to 29 mm), the aneurysmal noncoronary sinus, the moderately large annulus (valve annulus diameter greater than 30 mm), and the aneurysmal aortic root and dilated annulus. Implantation methods include the subcoronary technique, miniroot inclusion technique, and aortic root replacement. Technical variations such as valve inversion during implantation, valve rotation, and continuous or interrupted suture methods are important in certain techniques. The allograft aortic valve is a versatile device that can be used in the surgical management of the full range of aortic valve and aortic root pathology.

Aortic Valve↗
PubMed1998

Aortic valve replacement for octogenarians: are small valves bad?

BACKGROUND: As the population ages, more octogenarians become candidates for aortic valve replacement. Many octogenarians, particularly women, have a small aortic annulus and there is uncertainty as to the optimal management of this situation in that age group. METHOD: To examine this issue, we reviewed 248 octogenarians (mean age, 82.6 +/- 2.3 years; 58% men) who underwent primary isolated aortic valve replacement (n = 99), or aortic valve replacement and coronary revascularization (n = 149), between 1980 and 1995. Nineteen-millimeter valves were used in 26% of the patients. RESULTS: In-hospital mortality was 8.9%, 5% for aortic valve replacement alone and 11.4% for aortic valve replacement and coronary revascularization. It was 12.5% for the 19-mm size valves compared with 7.7% for the bigger size valves (p = 0.24). Follow-up (mean interval, 4.4 years) demonstrated survival for all patients of 85%, 60%, and 30% and survival free from cardiovascular events of 80%, 45%, and 21% at 1, 5, and 10 postoperative years, respectively. Multivariate analysis identified triple-vessel disease and preoperative congestive heart failure as associated with increased risk for both in-hospital and late mortality (p < 0.05). Valve size did not influence late survival or event-free survival regardless of body surface area. CONCLUSIONS: The use of small aortic valve prostheses in octogenarians does not adversely affect the incidence of early or late mortality or cardiac events.

Aged↗
PubMed2006

Valve repair in aortic regurgitation without root dilatation--aortic valve repair.

BACKGROUND: Aortic valve repair was established in the context of aortic root remodeling. Variable results have been reported for isolated valve repair. We analyzed our experience with isolated valve repair and compared the results with those of aortic root remodeling. METHODS: Between October 1995 and August 2003, isolated repair of the aortic valve was performed in 83 patients (REP), remodeling of the aortic valve in 175 patients (REMO). The demographics of the two groups were comparable (REP: mean age 54.4 +/- 20.7 yrs, male-female ratio 2.1 : 1; REMO: mean age 60.8 +/- 13.6 yrs, male-female ratio 2.4 : 1; p = ns). In both groups the number of bicuspid valves was comparable (REP: 41 %, REMO: 32 %; p = ns). All patients were followed by echocardiography for a cumulative follow-up of 8204 patient months (mean 32 +/- 23 months). RESULTS: Overall in-hospital mortality was 2.4 % in REP and 4.6 % in REMO ( p = 0.62). Systolic gradients were comparable in both groups (REP: 5.8 +/- 2.2, REMO: 6.5 +/- 3.1 mm Hg, p = 0.09). The mean degree of aortic regurgitation 12 months postoperatively was 0.8 +/- 0.7 after REP and 0.7 +/- 0.7 after REMO ( p = 0.29). Freedom from significant regurgitation (> or = II degrees ) after 5 years was 86 % in REP and 89 % in REMO ( p = 0.17). Freedom from re-operation after 5 years was 94.4 % in REP and 98.2 % in REMO ( p = 0.33). CONCLUSIONS: Aortic regurgitation without concomitant root dilatation can be treated effectively by aortic valve repair. The functional results are equivalent to those obtained with valve-preserving root replacement. Aortic valve repair appears to be an alternative to valve replacement in aortic regurgitation.

Adult↗
PubMed1999

A profile of valve replacement surgery in the UK (1986-1997): a study from the UK Heart Valve Registry.

BACKGROUND AND AIM OF THE STUDY: Approximately 150,000 heart valves are implanted annually world-wide, of which 4% are implanted in the UK. We present a comprehensive profile of the trends in valve replacement (VR) surgery in the UK since 1986 based on data from the UK Heart Valve Registry (UKHVR). METHODOLOGY: The UKHVR is a computerized database collecting prospective data on VR surgery in all UK cardiac units. All patients are tracked by national agencies who register all deaths of UK residents. Thus, the Registry receives a copy of each patient's death certificate and enters the date, place and certified cause(s) of death on the database. RESULTS: Between January 1st 1986 and December 31st 1997, a total of 58,195 patients underwent first-time VR surgery and received 63,649 valves. Mean age at operation in 1986 was 58.7 years (range: 18-87 years) and this rose to 64.7 years (range: 18-94 years) in 1997. In 1986, 12% (n = 578) of patients who underwent VR surgery were aged >70 years compared with 36% (n = 5125) in 1997. There was a 4% decrease in double VR surgery and a 15% reduction in mitral VR between 1986 and 1997. The majority of patients received a mechanical valve; within this group the number of bileaflet valve implants increased significantly since 1986. There has been a reversal in the downward trend in pericardial valves implanted since 1993. Follow up was 96.1% complete, with a total of 342,993 patient-years. Mortality (30-day) fell from 6.9% in 1986 to 3.8% in 1995, but increased to 6.7% in the two years to 1997. Actuarial survival at 1, 5 and 10 years was 89.5%, 78.5% and 61.8%, respectively; confidence intervals of 0.5% reflect the enormity of the database and quality of the data. CONCLUSIONS: UKHVR data can provide comprehensive year-by-year and trend analyses in a database in excess of 63,000 valves. Changes in patient demographics, choice of implanted valve and the pattern of heart valve disease are evident within the UK over the past 11 years.

Adolescent↗
PubMed1978

Hemodynamic characteristics of the composite strut ball valve prostheses (Starr-Edwards track valves) in patients on anticoagulants.

The hemodynamic characteristics of the composite strut ball valve prostheses (Starr-Edwards Model 2400 aortic track valve and Model 6400 mitral track valve) were evaluated in anticoagulated patients. The peak systolic gradient (mean +/- SE) for the aortic valve in 16 patients was 18.1 +/- 3.9 mm Hg; the mean gradient was 17.0 +/- 2.7 mm Hg; the prosthetic valve area was 1.7 +/- 0.1 cm2; and the valve area index was 1.0 +/- 0.1 cm2/m2. In the 19 patients with the mitral valve, the mean diastolic gradient (mean +/- SE) was 5.2 +/- 0.7 mm Hg. The prosthetic valve area was 2.0 +/- 0.1 cm2, and the valve area index was 1.3 +/- 0.1 cm2/m2. These hemodynamic parameters are helpful in evaluating the catheterization findings in patients with composite strut prosthetic valves who are suspected of having prosthesis dysfunction. They also demonstrate the satisfactory in vivo hemodynamics in anticoagulated patients with these prostheses.

Adult↗
PubMed2005

Prosthetic valve hemodynamics assessed by the left ventricular outflow tract area utilization index: a randomized study of the carbomedics reduced versus the Medtronic Hall valve.

BACKGROUND AND AIM OF THE STUDY: Continuous changes are made in valve prosthesis design in order to improve hemodynamic performance. In this prospective, randomized study, hemodynamic properties of the bileaflet CarboMedics Reduced (CM-R) valve with a thinner sewing ring was compared to the Medtronic Hall (MH) disc valve. Special emphasis was placed on the ability of the two valve types to make the most effective use of the available left ventricular outflow tract (LVOT) area as defined by preoperative echocardiographic measurements. METHODS: Twenty patients scheduled for a mechanical aortic valve prosthesis were randomized to receive either a CM-R or MH valve. Only patients receiving a prosthesis < or = 25 mm were included. A complete Doppler echocardiographic study was performed preoperatively and at six months postoperatively. Transprosthetic gradients, effective orifice area (EOA), effective orifice area index (EOAI) and LVOT-utilization index (LVOT-UI; defined as EOA/preoperative LVOT area) were compared. RESULTS: The CM-R valve was superior to the MH valve for all hemodynamic parameters studied: EOA 2.03 +/- 0.50 versus 1.56 +/- 0.20 cm2 (p < 0.01); EOAI 1.07 +/- 0.22 versus 0.83 +/- 0.13 cm2/m2 (p = 0.01); and LVOT-UI 0.47 +/- 0.09 versus 0.38 +/- 0.05 (p = 0.001). Although cardiac output was significantly higher in the CM-R group, transprosthetic gradients were lower (peak 21 +/- 5 versus 27 +/- 5 mmHg (p = 0.02); mean 11 +/- 4 versus 13 +/- 2 mmHg (p = 0.07)). CONCLUSION: The results of this study showed that the CM-R aortic valve offers favorable hemodynamics compared to the MH valve. The inclusion of preoperative LVOT area measurements (as LVOT-UI) showed that the CM-R offers a more effective use of the available LVOT area.

Aortic Valve↗
PubMed1991

[The mitral valve in mitral valve defect. Histological and clinical correlations].

The purpose of this study was to investigate the correlation between the histologic changes in the excised mitral valves and the clinical findings in patients with mitral stenosis (with or without regurgitation). The Study group consists of 26 men and 23 women ranged in age from 24 to 56 years. The mitral valves were removed in a uniform manner by one surgeon during mitral valve replacement. The controls were 13 mitral valves removed at necropsy from patients who died of extracardiac causes. Excised valves were fixed in 5% solution of formaline. The extent of calcification was determined by radiographs. Tissue from the center of the anterior and posterior leaflet were selected as the samples. The blocks were paraffin embedded and processed in the conventional manner. For histological examination 11.5 um thick sections were stained with haematoxylin and eosin, Alcian blue, Van Gieson and Von Koss stain. Then the sections were examined under light microscope. We estimated the degree of fibrotic disorganization of architecture, vascularization, acid mucopolysaccharide content, number of fibroblasts, and the presence of calcific deposits and lymphoid infiltrates. The control valves had normal architecture with thick "fibrosa". In all stenotic mitral valves we found complete or partial disorganization of architecture. The most common change was hyalinization present in 94% valves, vascularization in 84% and calcification present in 66% of valves. In 33% of stenotic valves were present infiltrations by lymphocytes. We found a significant correlation (p less than 0.05) between the presence of lymphoid infiltrates and the duration of disease prior to surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗