Frequency and extent of calcific deposits in purely regurgitant mitral valves: Analysis of 108 operatively excised valves

Operatively excised purely regurgitant mitral valves in 108 patients aged 21 to 73 years (mean 55) (63% men) undergoing isolated mitral valve replacement were examined for calcific deposits. Of the 108 patients, 19 (18%) had leaflet or chordal calcific deposits or both, but in each the deposits were small and did not appear to alter mitral function. Of the 19 patients with mitral calcium, 6 had had active infective endocarditis and the calcium likely represented healed vegetations; In 6 other patients, the leaflet calcium had extended from the mitral anulus in the setting of mitral valve prolapse. The average total serum cholesterol levels were higher in the patients with compared with those without mitral calcium. Thus, calcium deposits are relatively infrequent in adults with clinically isolated pure mitral regurgitation, and when they occur, the deposits are small and in themselves do not appear to contribute to mitral dysfunction.     

In vitro analysis of mechanisms of balloon valvuloplasty of stenotic mitral valves

Preliminary reports indicate that percutaneous balloon valvuloplasty is efficacious for treatment of mitral stenosis. The present study was designed to evaluate whether anatomic features of stenotic mitral valves in older adults affect the efficacy of balloon valvuloplasty and to determine the mechanism by which increased orifice area is accomplished. Fifteen mitral valves excised intact at the time of mitral valve replacement from patients with no more than 2+/4+ mitral a regurgitation were selected for study. Balloon valvuloplasty was performed using a sequence of dilation catheters with balloons 18 to 25 mm in inflated diameter. Mitral valve area, measured with a conical valve sizer, increased from 0.71 +/- 0.06 cm2 (mean +/- standard error of the mean) to 1.77 +/- 0.19 cm2 (p less than 0.0001) after valvuloplasty, resulting in an increase in calculated orifice area of 185 +/- 27% (range 34 to 407%). The increase in calculated orifice area correlated inversely with orifice area before valvuloplasty (r = -0.57; p = 0.026), but was unrelated to extent of calcific deposits on the prevalvuloplasty x-ray of the excised mitral valve. Gross examination together with x-ray analysis after valvuloplasty revealed that the mechanism of balloon valvuloplasty in each case involved commissural splitting, including splits through heavily calcified commissures, without grossly apparent detachment of tissue fragments. These findings suggest that balloon valvuloplasty augments the functional mitral valve orifice area in a manner analogous to standard surgical commissurotomy, and balloon valvuloplasty is likely to be efficacious for a wide spectrum of adult mitral valvular stenosis, including severe stenosis with extensive calcific deposits.     

Percutaneous transvenous mitral commissurotomy: immediate and long-term follow-up results.

Percutaneous transvenous mitral commissurotomy has emerged as an effective nonsurgical technique for the treatment of patients with symptomatic mitral stenosis. This report highlights the immediate and long-term follow-up results of this procedure in an unselected cohort of patients with rheumatic mitral stenosis from a single center. It was performed in a total of 4,850 patients using double balloon in 320 (6.6%), flow-guided Inoue balloon technique in 4,374 (90.2%), and metallic valvulotome in 156 (3.2%) patients. Their age range was 6.5-72 years (mean, 27.2 +/- 11.2 years) and 1,552 (32%) patients were under 20 years of age. Atrial fibrillation was present in 702 (14.5%) patients. No patient was rejected on the basis of echocardiographic score using the Wilkins criteria. Echocardiographic score of > or = 8 was present in 1,632 (33.6%) patients, of which 103 (2.1%) had densely calcified (Wilkins score 4+) valve. A detailed clinical and echocardiographic (two-dimensional, continuous-wave Doppler and color-flow imaging) assessment was done at every 3 months for the first year and at 6-month interval thereafter. The procedure was technically successful in 4,838 (99.8%) patients but optimal result was achieved in 4,408 (90.9%) patients with an increase in mitral valve area (MVA) from 0.7 +/- 0.2 to 1.9 +/- 0.3 cm(2) (P < 0.001) and a reduction in mean transmitral gradient from 29.5 +/- 7.0 to 5.9 +/- 2.1 mm Hg (P < 0.001). The mean left atrial pressure decreased from 32.1 +/- 9.8 to 13.1 +/- 6.2 mm Hg (P < 0.001). Although there was no statistically significant difference in the MVA achieved between de novo and restenosed valves (1.9 +/- 0.3 and 1.8 +/- 0.2 cm(2), respectively; P > 0.05), or between noncalcific and calcific valves (2.0 +/- 0.3 and 1.8 +/- 0.2 cm(2), respectively; P > 0.05), on the whole MVA obtained after percutaneous transvenous mitral commissurotomy was less in restenosed and calcific valves. Ten (0.20%) patients had cardiac tamponade during the procedure. Mitral regurgitation appeared or worsened in 2,038 (42%) patients, of which 68 (1.4%) developed severe mitral regurgitation. Urgent mitral valve replacement was carried out in 52 (1.1%) of these patients. Data of 3,500 patients followed over a period of 94 +/- 41 months (range, 12-166 months) revealed MVA of 1.7 +/- 0.3 cm(2). Elective mitral valve replacement was done in 34 (0.97%) patients. Mitral restenosis was seen in 168 (4.8%) patients, of which 133 (3.8%) were having recurrence of class III or more symptoms. Thus, percutaneous transvenous mitral commissurotomy is an effective and safe procedure with gratifying results in high percentage of patients. The benefits are sustained in a majority of these patients on long-term follow-up. It should be considered as the treatment of choice in patients with rheumatic mitral stenosis of all age groups.     

Calcification of prosthetic valve anuli: A late complication of cardiac valve replacement

A previously undescribed late complication of cardiac valve replacement is calcification at the site of attachment of prostheses. Of 24 patients in whom purely incompetent, non-calcified mitral or aortic valves were replaced with rigid-framed prostheses 3 to 116 months earlier, nine (seven mitral, two aortic) of 26 valves had prosthetic anular calcific deposits. Of the eight prostheses in place for 70 months or longer all contained anular calcific deposits; only one of the 18 valves in place for less than 70 months had periprosthetic calcific deposits. The extent of prosthetic calcium also increased with time. The mechanism of formation of prosthetic anular calcium is uncertain, but accelerated wear of the tissues beneath the prostheses due to the constant to-and-fro motion of the rigid frames may be a factor. Possible complications of prosthetic anular calcific deposits include suture rupture, peribasilar leak, and increased hazard to reoperation.     

In vivo identification of mitral valve fibrosis and calcium by real-time quantitative ultrasonic analysis

Conventional echocardiography provides fundamental information about mitral valve morphology and function but has a relatively low specificity in evaluating valve calcific deposits, which is critical information for the preoperative decision to perform commisurotomy or replacement. In vitro radiofrequency ultrasonic quantitative analysis of the mitral valve has been demonstrated to be a reliable tool in identifying normal, fibrotic and calcific valves. This study evaluates quantitative ultrasound characterization of the mitral valve in vivo. Thirty-three patients, scheduled to undergo mitral valve replacement, and 20 normal subjects (10 young and 10 older control subjects) were studied with a 2.25-MHz transducer. Radiofrequency signal was analyzed by a microprocessor system (used with an M-mode commercially available echocardiograph) for on-line evaluation of ultrasonic backscatter with 8 bits of amplitude resolution, 40-MHz sampling rate and a 1-microsecond acquisition gate. The integrated value of the rectified radiofrequency signal amplitude was deemed the integrated backscatter index. The highest value recorded with the ultrasonic analysis from each valve was taken as representative and expressed as the percent value with respect to the pericardial integrated backscatter index value of that subject. The 33 excised mitral valves underwent histologic examination. Four groups were identified: young controls (group I, n = 10); older controls age-matched with patients (group II, n = 10); patients with fibrotic mitral valves (group III, n = 13); and patients with calcific mitral valves (group IV, n = 20).(ABSTRACT TRUNCATED AT 250 WORDS)     

Severe mitral or aortic valve regurgitation, or both, requiring valve replacement for infective endocarditis complicating hypertrophic cardiomyopathy.

Certain clinical and morphologic findings are described in 11 patients with hypertrophic cardiomyopathy complicated by infective endocarditis that produced severe mitral or aortic valve regurgitation, or both, necessitating valve replacement. All 11 patients had changes in the operatively excised valve or valves characteristic of healed infective endocarditis. The infection involved only the mitral valve in seven patients, only the aortic valve in three patients and both valves in one patient. Study of the operatively excised mitral valves indicated that the healed vegetations were located most commonly on the left ventricular aspects of the anterior mitral leaflet, indicating that vegetation had formed at contact points of this leaflet with mural endocardium of the left ventricular outflow tract. In all 11 patients, the infective endocarditis either worsened preexisting valve regurgitation or initiated valve regurgitation and led to worsened signs and symptoms of cardiac dysfunction, necessitating valve replacement. Functional class improved in the nine patients who survived 7 to 101 months after valve replacement. Hypertrophic cardiomyopathy appears to be a factor predisposing to infective endocarditis. Patients with hypertrophic cardiomyopathy should receive prophylactic antibiotic therapy during procedures that predispose to infective endocarditis.     

Echocardiographic evaluation of porcine bioprosthetic valves: Experience with 309 normal and 59 dysfunctioning valves

To determine the clinical value of echocardiographic evaluation of porcine bioprosthetic valves, the findings in all patients who had porcine bioprosthetic valve replacement and adequate quality echocardiographic studies from 1978 to 1982 were analyzed. The study includes 309 normal and 59 dysfunctioning valves. Valve dysfunction resulted from spontaneous cusp degeneration in 39 (34 valve regurgitations, 5 stenoses), infective endocarditis in 12, paravalvular regurgitation in 5, regurgitation of redundant cusps, mitral valve thrombi, and aortic stent stenosis in 3 others. Echocardiographic findings were correlated with gross surgical pathologic or autopsy findings in 45 of the 59 dysfunctioning valves. Echocardiographic abnormalities were demonstrated in 41 of 59 (69%) dysfunctioning valves. A systolic mitral or diastolic aortic valve flutter was diagnostic of a regurgitant valve caused by a torn or unsupported cusp margin and was observed in 28 of 34 (82%) regurgitant valves with no false-positive studies. Echocardiographic cusp thickness of ≥ 3 mm correctly identified all regurgitant and stenotic valves with gross anatomic evidence of localized or generalized cusp thickening or calcific deposits. Echocardiographic valve abnormalities were observed in only 4 of 12 patients with infective endocarditis and in 1 of 5 with paravalvular regurgitation.Thus, echocardiography provides important information regarding the function of porcine bioprosthetic valves and is of value in the decision to replace these valves, especially when dysfunction is due to spontaneous cuspal degeneration. Echocardiography is neither sensitive nor specific in patients with infective endocarditis and paravalvular regurgitation.     

Presence of a congenitally bicuspid aortic valve among patients having combined mitral and aortic valve replacement

Although bicuspid aortic valve occurs in an estimated 1% of adults and mitral valve prolapse in an estimated 5% of adults, occurrence of the 2 in the same patient is infrequent. During examination of operatively excised aortic and mitral valves because of dysfunction (stenosis and/or regurgitation), we encountered 16 patients who had congenitally bicuspid aortic valves associated with various types of dysfunctioning mitral valves. Eleven of the 16 patients had aortic stenosis (AS): 5 of them also had mitral stenosis, of rheumatic origin in 4 and secondary to mitral annular calcium in 1; the other 6 with aortic stenosis had pure mitral regurgitation (MR) secondary to mitral valve prolapse in 3, to ischemia in 2, and to unclear origin in 1. Of the 5 patients with pure aortic regurgitation, each also had pure mitral regurgitation: in 1 secondary to mitral valve prolapse and in 4 secondary to infective endocarditis. In conclusion, various types of mitral dysfunction severe enough to warrant mitral valve replacement occur in patients with bicuspid aortic valves. A proper search for mitral valve dysfunction in patients with bicuspid aortic valves appears warranted.     

Intraoperative contrast echocardiography to evaluate mitral valve operations

Intraoperative two-dimensional contrast echocardiography was performed on 29 patients undergoing open heart surgery to determine the presence of mitral regurgitation before and immediately after the operative procedure: 14 patients had predominant mitral stenosis, 9 had severe mitral regurgitation and 6 had no mitral valve disease (control subjects). Two-dimensional echocardiography was performed by applying a 5 MHz transducer directly on the heart during injection of saline solution through an apical ventricular sump or transseptal needle, generating contrast microbubbles, with imaging in two planes. Baseline studies were performed after thoracotomy and pericardiotomy before cardiopulmonary bypass, and a second study was done after the operative procedure, with the patient off cardiopulmonary bypass with hemodynamic stabilization before chest closure. No control subject had contrast evidence of mitral regurgitation before or after cardiopulmonary bypass. Two of three patients with mitral valvuloplasty and two of five with commissurotomy required a second operative procedure before chest closure because of persistent mitral regurgitation detected by intraoperative two-dimensional contrast echocardiography. Thirteen of the 15 patients with valve replacement had no mitral regurgitation after cardiopulmonary bypass. Intraoperative two-dimensional echocardiographic findings correlated with data from postoperative clinical examinations and two-dimensional echocardiography-Doppler studies. It is concluded that two-dimensional echocardiography with contrast is an important intraoperative tool for assessing the presence and relative severity of mitral regurgitation after mitral commissurotomy, valvuloplasty or valve replacement. This technique may allow surgeons to be more aggressive in combining reparative operative procedures (that is, commissurotomy and valvuloplasty) in an attempt to retain native valves.     

Valve dysfunction of the cloth-covered Starr-Edwards ball valve.

BACKGROUND: Between June 1968 and March 1977, Starr-Edwards cloth-covered ball valves were used for valve replacement on a routine basis. METHODS AND RESULTS: Among the 66 operative survivors who underwent an isolated aortic or mitral valve replacement, 20 patients required reoperation 22 times because of valve dysfunction, thromboembolic complication, paravalvular leakage, hemolytic anemia, and/or prosthetic valve endocarditis. Reoperation was performed at a mean of 15.9+/-9.8 years after initial replacement. Excised valves were examined and reoperation after initial operation was reviewed. Operative mortality was 10.0%. Freedom from reoperation for aortic valve replacement and mitral valve replacement was 56.2% at 34 years and 61.0% at 37 years after initial operation, respectively. Cloth wear or pannus formation were observed in all excised prostheses. Orifice cloth was more markedly worn in mitral valves than in aortic valves, particularly in mitral valves of more than 20 years old. Pannus overgrowth contributed to valve regurgitation in the older valves. CONCLUSIONS: Early diagnosis of valve dysfunction and reoperation are recommended as soon as symptoms appear.     

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)     

Percutaneous balloon mitral commissurotomy during pregnancy.

OBJECTIVE: To evaluate the effectiveness and safety of percutaneous balloon mitral commissurotomy for the treatment of pregnant women with severe mitral stenosis over a period of six years. DESIGN: Analysis of clinical, haemodynamic, and echocardiographic data before and immediately after the procedure, the pregnancy outcome, and the fate of newborn babies. SETTING: Academic cardiovascular centre in Monastir, Tunisia. PATIENTS: 44 pregnant patients who underwent percutaneous transvenous dilatation of the mitral valve between January 1990 and February 1996. Grade 2 mitral regurgitation was present in two patients and densely calcific valves in three (7%). RESULTS: Commissurotomy was successfully achieved in all cases. The total mean (SD) duration of teh procedure was 72 (18) minutes and that of fluoroscopy 16 (7) minutes. Left atrial pressure decreased from 28 (10) to 14 (7) mm Hg, mitral pressure gradient fell from 22 (8) to 5 (3) mm Hg. Cardiac output increased from 4.8 (1.1) to 6.3 (1.2) l/min and Gorlin mitral valve area from 0.96 (0.21) to 2.4 (0.4) cm2 (all P < < 0.001). Cross sectional echocardiographic mitral valve area increased from 1.07 (0.21) to 2.32 (0.36) cm2. There were no maternal or fetal deaths. Complications included a grade 4 mitral regurgitation in one patient that required early valve replacement. All patients delivered at full term, 42 vaginally and two (5%) by caesarean section; 41 babies were normal and three whose mothers had the procedure near term were relatively hypotrophic. At a mean follow up of 28 (12) months (range 2 to 26) all children had normal growth. CONCLUSIONS: During pregnancy, balloon mitral commissurotomy is the treatment of choice of severe pliable mitral stenosis in patients who are refractory to medical treatment.     

Experimental balloon valvuloplasty of fibrotic and calcific mitral valves

This study evaluated the mechanism of valvular area expansion during single- and double-balloon valvuloplasty in fibrotic and calcific mitral valves. Special interest was focused on the morphological features of the valves treated. Mitral valves that appeared unsuitable for commissurotomy were excised in toto at the time of mitral valve replacement in 15 patients. The excised valves were mounted in a fluid-filled chamber with a window for photographic evaluation. The chamber was perfused continuously to ensure maximal valvular opening. The valve was photographed, and the orifice area was measured before and after balloon expansion. In addition, the specimens were examined macroscopically and radiographically with regard to calcium content and degree and localization of fibrosis. These data were correlated with splitting of commissures and with rupture of leaflets. Nine valves were fibrotic, and six were calcific. Dilatation was performed first with a single-balloon catheter (diameter, 2 cm) and then with a double-balloon catheter (diameter, 2 and 1.5 cm). After dilatation with one balloon, the average mitral valve area increased from 0.79 to 1.09 cm2, and with two balloons, average area increased to 1.59 cm2. The single-balloon technique caused commissural splitting in nine valves, stretching in three, partial leaflet rupture in one, and no change in two. After the double-balloon technique, commissural splitting occurred in 12 valves and three leaflets were ruptured where severe fibrosis and calcification were mainly located within the commissures. As a rule, after dilatation with the single-balloon technique, the remaining stenosis was still severe, and after dilatation with the double-balloon technique, the remaining stenosis was moderate.(ABSTRACT TRUNCATED AT 250 WORDS)     

Clinical and anatomic observations in patients having mitral valve replacement for mitral stenosis and simultaneous tricuspid valve replacement

Certain clinical and morphologic findings are described in 67 patients (aged 23 to 76 years [mean 52]; 55 women [82%]) who had mitral valve replacement for mitral stenosis (with or without associated regurgitation), and simultaneous tricuspid valve replacement for pure tricuspid regurgitation (58 patients) or tricuspid stenosis (all with associated regurgitation; 9 patients). Of the 58 patients with pure tricuspid regurgitation, 21 had anatomically normal and 37 had anatomically abnormal (diffusely fibrotic leaflets) tricuspid valves. Among these 58 patients, no clinical or hemodynamic variable was useful before surgery in distinguishing the group without from that with anatomically abnormal tricuspid valves. All 9 patients with stenotic tricuspid valves had anatomically abnormal tricuspid valves. The latter group had a lower average right ventricular systolic pressure (tricuspid valve closing pressure) than those with pure tricuspid regurgitation, and none had severe pulmonary arterial hypertension (present in 20 [30%] of the 58 patients with pure tricuspid regurgitation).     

Surgical indications in mitral valve stenosis, combined mitral valve defect or mitral valve insufficiency. Long-term prognosis of operated or drug-treated patients

Data obtained from 683 patients with mitral valve disease, NYHA-class III or IV, were retrospectively studied by means of a multivariate Cox regression analysis. Based on symptoms and hemodynamic findings, surgical intervention had been recommended for all patients: closed mitral commissurotomy (n = 361), prosthetic mitral valve replacement (n = 241) and prosthetic mitral valve replacement together with a corrective procedure for the tricuspid valve (n = 81). While the majority of patients underwent surgery during the observation period (n = 528), a substantial number of patients continued on medical treatment (n = 155). The mean observation periods were 52, 49 and 31 months, respectively, in the three collectives. Surgically treated patients in whom closed mitral commissurotomy had been recommended had a better prognosis (p less than 0.0003) than those treated medically (five-year survival rate 89% vs. 63%). Age, clinical severity, previous mitral commissurotomy, pulmonary vascular resistance and right atrial mean pressure had no significant influence on prognosis. In patients in whom prosthetic mitral valve replacement had been recommended, surgical treatment led only to tendencial improvement in prognosis as compared with those treated medically (five-year survival rate 78% vs. 61%). Factors with an unfavorable influence on prognosis were age more than 49 years (p less than 0.05), pure mitral regurgitation (p less than 0.001), NYHA-class IV (p less than 0.02) and right atrial mean pressure in excess of 4 mm Hg (p less than 0.01). In patients in whom prosthetic mitral valve replacement together with a corrective procedure for the tricuspid valve had been considered necessary, surgical treatment had no significant influence on prognosis as compared with those treated medically (five-year survival rate 57% vs. 53%). Patients in whom previous mitral commissurotomy had been performed had an extremely poor prognosis (p less than 0.001). Pulmonary vascular resistance was significantly reduced both after mitral commissurotomy as well as after prosthetic mitral valve replacement; this was associated with a significant decrease in right atrial mean pressure and increase in right ventricular ejection fraction. The indication for closed mitral commissurotomy, thus, appears established in patients with symptoms of class III or IV clinical severity. The indication can be established generously since the surgical mortality is low and long-term prognosis is good.(ABSTRACT TRUNCATED AT 400 WORDS)     

Percutaneous transvenous mitral commissurotomy for significant calcific mitral stenosis: utility of the stepwise balloon dilatation technique and follow-up results

The present study examined the utility of the stepwise balloon dilatation technique in 41 patients with significant calcific mitral stenosis undergoing percutaneous transvenous mitral commissurotomy (PTMC). Thirty-five patients (85.4%) had a successful procedure; one patient developed cardiac tamponade and underwent mitral valve replacement. The mitral valve area increased from 0.9 +/- 0.2 cm2 to 1.7 +/- 0.3 cm2 following PTMC. Increase in mitral regurgitation (MR) was seen in 11 patients (26.8%). All patients showed improvement in functional class of > or =1 level following PTMC, which was sustained in 34 patients at follow-up. At a mean follow-up period of 20 +/- 12 months (range 3-51 months) in 35 patients, 26 patients (74.3%) were in New York Heart Association (NYHA) functional Class I, 8 patients (22.9%) were in NYHA Class II, and 1 patient (2.8%) was in NYHA Class III. The cumulative 4-year cardiac event-free survival rate was 81.8%. However, patients with grade 4+ calcification had only 50% event-free survival rate. At follow-up, an increased incidence of cardiac events was seen in female patients as compared with male patients (83.3% versus 16.7%). Restenosis was seen in 3 patients (8.6%). One patient underwent repeat PTMC 37 months after the initial procedure. There was no incidence of death or mitral valve replacement at follow-up. We conclude that the stepwise balloon dilatation technique can be safely and effectively applied for patients with significant calcific mitral stenosis to achieve an optimal mitral valve area with low incidence of significant increase in MR. Favorable long-term benefits also accrue in the form of improved functional status and low incidence of repeat procedures (repeat PTMC or mitral valve replacement). The majority of patients (74.3%) were in NYHA functional class I without medication. Patients with grade 4+ calcification show less benefit from PTMC and may be considered for mitral valve replacement. Cardiac events occur more frequently in female patients than in male patients during follow-up.     

Morphologic features of the normal and abnormal mitral valve

Anatomic and functional features of the normal and abnormal mitral valve are reviewed. Of 1,010 personally studied necropsy patients with severe (functional class III or IV, New York Heart Association) cardiac dysfunction from primary valvular heart disease, 434 (43%) had mitral stenosis (MS) with or without mitral regurgitation (MR): unassociated with aortic valve stenosis or regurgitation or with tricuspid valve stenosis in 189 (44%) patients, and associated with aortic stenosis in 152 (35%), with pure (no element of stenosis) aortic regurgitation in 65 (15%) patients, and with tricuspid valve stenosis with or without aortic valve stenosis in 28 (6%) patients. The origin of MS was rheumatic in all 434 patients. Of the 1,010 necropsy patients, 165 (16%) had pure MR (papillary muscle dysfunction excluded): unassociated with aortic valve stenosis or regurgitation or with tricuspid valve stenosis in 97 (59%) patients, and associated with pure aortic regurgitation in 45 (27%) and with aortic valve stenosis in 23 (14%) patients. When associated with dysfunction of the aortic valve, pure MR was usually rheumatic in origin, but when unassociated with aortic valve dysfunction it was usually nonrheumatic in origin. Review of operatively excised mitral valves in patients with pure MR unassociated with aortic valve dysfunction disclosed mitral valve prolapse (most likely an inherent congenital defect) as the most common cause of MR. Excluding the patients with MR from coronary heart disease (papillary muscle dysfunction), mitral prolapse was the cause of MR in 60 (88%) of the other 68 patients, and a rheumatic origin was responsible in only 3 of the 68 patients, all 68 of whom were greater than 30 years of age. Mitral anular calcification in persons aged greater than 65 years is usually associated with calcific deposits in the aortic valve cusps and in the coronary arteries. Because calcium in each of these 3 sites is common in older individuals residing in the Western World, it is most reasonable to view mitral anular calcification in older individuals as a manifestation of atherosclerosis. Mitral anular calcium appears to be extremely uncommon in persons with total serum cholesterol levels less than 150 mg/dl. Mitral anular calcium may produce mild MR and, if the deposits are heavy enough, MS.     

Valvuloplasty with balloon catheter in biologic prosthesis. Reality or illusion

We performed catheter balloon valvuloplasty (CBV) on 8 stenotic operatively-excised bioprosthetic valves (2 Hancock and 6 Ionescu Shiley). Pathology of valves before CBV included degenerative changes: commissural fusion by mounds of calcific deposits (2 valves), fibrotic and focally calcified leaflets (7 valves) and stiff and thick valves (1 valve). Inflation of the balloon resulted in commissural splitting (2 valves), leaflet cracks and fractures (3 valves). Removal of the deflated balloon catheter was associated with debris dislodgement (3 valves). In one case the valve was unable to close with potential for acute regurgitation. Thus, CBV of bioprosthetic valves can split fused commissures by similar mechanisms as in native valves. CBV may fracture calcific deposits causing acute emboli. It can also disrupt the leaflets causing acute insufficiency. The findings suggest a limited role of CBV in the treatment of stenotic bioprosthetic valves in mitral and aortic position.     

Urgent/Emergent percutaneous transvenous mitral commissurotomy

Urgent/emergent percutaneous transvenous mitral commissurotomy (PTMC) was performed in 10 patients (two men and eight women, aged 21 to 60 yr). All patients had arterial hypoxemia and four required mechanical respirators. PTMC was performed in the semi-recumbent position in four patients. The seven patients with pliable valves (group 1) achieved good hemodynamic and echocardiographic results after PTMC, but one died 2 wk later because of sepsis complicating preexisting pneumonitis. The two pregnant patients uneventfully delivered normal babies at term. There was continued clinical improvement in the six surviving patients at last follow-up at 11 to 39 mon (median 26). Of the three patients with calcified valves and severe subvalvular lesions (group 2), the premoribund patient in whom last-resort PTMC created severe mitral regurgitation died 3 days later of multiple organ failure. The other two patients underwent mitral valve replacement 1–6 days later because of lack of clinical improvement due to creation of severe mitral regurgitation and ineffective mitral valve dilation, respectively. In conclusion, urgent/emergent PTMC is feasible and safe. However, its outcomes are dictated by the status of diseased mitral valve and coexisting illness.     

Replacement of an aortic Starr-Edwards ball valve prosthesis 28 years after implantation.

A 53-year-old woman who had undergone aortic valve replacement with a Starr-Edwards (S-E) valve (Model 1260) and open mitral commissurotomy 28 years previously was hospitalized with cardiac failure. Echocardiography showed mitral stenosis, mitral regurgitation, and a normally functioning S-E prosthesis. At reoperation, the mitral and aortic valves were replaced with St Jude bileaflet mechanical prostheses. Examination of the explanted S-E prosthesis revealed no structural abnormality other than lipid infiltration of the silastic ball.