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Late clinical and echocardiographic follow up after percutaneous balloon dilatation of the mitral valve.

OBJECTIVE: To assess the outcome after attempted percutaneous balloon dilatation of the mitral valve in patients with severe mitral stenosis between February 1986 and June 1992. DESIGN: Clinical state, mitral valve area, and restenosis at follow up were analysed. Mitral valve area as determined by the Gorlin formula, planimetry, and Doppler methods was compared before and after dilatation and at follow up. SETTING: University hospital. PATIENTS: 176 patients had serial clinical and Doppler echocardiographic follow up and 44 of them also underwent recatheterisation. RESULT: At follow up 93% of patients were in New York Heart Association functional class I or class II. Mitral valve area (planimetry) increased from 0.97(0.24) cm2 before to 1.86(0.39) cm2 after dilatation (p = 0.0001) and then decreased to 1.72(0.39) cm2 at follow up (p < 0.001); mitral valve area (Doppler) increased from 1.01 (0.24) to 1.89 (0.42) cm2 (p = 0.0001) and then decreased to 1.78(0.40) cm2 (p < 0.05). The overall restenosis rate was 15% and over 90% of the patients were free from cardiovascular events. Age, valvar calcification, echocardiographic score, and mitral valve area after dilatation were found to be determinant predictors of restenosis. In patients who underwent recatheterisation, mitral valve area by the Gorlin method at follow up was comparable with that by planimetry and Doppler methods whereas a significant discrepancy between the three methods was noted immediately after dilatation. CONCLUSION: Balloon dilatation of the mitral valve provided sustained anatomical and functional improvement in over 80% of patients at late follow up. Older age, heavy calcification, high echocardiographic score, and suboptimal immediate results are significant predictors of restenosis. Doppler echocardiographic examination is the procedure of choice for follow up evaluation.

Adolescent↗

[Left cerebral ischemia in mitral valve aneurysm].

An anterior mitral leaflet aneurysm was detected by two-dimensional echocardiography using the transesophageal approach in a 53-year-old patient with cerebral ischemic event. The transesophageal examination allowed a clear description of the aneurysm which was confirmed during surgery. This case demonstrates that transesophageal echocardiography is the method of choice in evaluation of distinct valvular lesions. The importance of TEE examination in patients with a neurological history is evident.

Aneurysm↗

[Criteria for the diagnosis of prolapsed mitral valve using phonocardiography and echocardiography].

Our criteria for the diagnosis of prolapsed mitral valve were proposed in this paper. With this abnormality, the principal alterations in the mitral valve consist of an abnormal systolic leaflet motion and mitral regurgitation with or without systolic clicks. Our criteria include: (1) auscultatory or phonocardiographic findings suggestive of mitral regurgitation or mitral complex abnormality, (2) a posterior displacement of the mitral valve throughout the latter half of systole by M-mode echocardiography, and (3) a systolic bulging or an apparent systolic ballooning of the mitral valve by two-dimensional echocardiography. A diagnosis of prolapsed mitral valve is justified in a given case if (1) plus one or two other findings are present. Several confusing M-mode and two-dimensional echocardiographic findings for the diagnosis of this condition are neglected in this criteria. We believe that the diagnosis of prolapsed mitral valve, as a rule, should depend on the presence of significant auscultatory or phonocardiographic finding which is a major manifestation of our criteria. However, our criteria seem to be inadequate for the diagnosis of a systolic ballooning of the mitral valve toward the left atrium which is frequently associated with atrial septal defect, since an apical systolic murmur is often absent. The mitral valve ballooning in atrial septal defect, however, is of functional origin, and should be differentiated from an organic prolapsed mitral valve. Thus, to be significant of prolapsed mitral valve, an apical auscultatory or phonocardiographic findings should be unequivocal.

Echocardiography↗

Mitral valve prolapse: associations with symptoms and anxiety.

Mitral valve prolapse has been studied extensively in the adult population, but less is known about it in children. Therefore, 813 children between 9 and 14 years of age were examined by a team of cardiologists and technicians. The children also responded to a questionnaire concerning the presence of symptoms and the What I Think and Feel anxiety instrument. The prevalence of mitral valve prolapse using auscultatory criteria was 4.2% (6.2% for girls, 2.3% for boys). Of those with mitral valve prolapse, 85% had a solitary click, 9% had a click and systolic murmur, and 6% had multiple clicks. Children with auscultatory mitral valve prolapse were less likely to have symptoms than those free of cardiac abnormalities. No difference in average anxiety scores was detected between the two groups. It is concluded that auscultatory mitral valve prolapse is common in children and not accompanied by an increased likelihood of symptoms or anxiety.

Adolescent↗

Cardiac function during rest and exercise in patients with mitral valve prolapse. Role of radionuclear angiocardiography.

The clinical features of mitral valve prolapse syndrome and ischemic coronary disease overlap, making differentiation of the two conditions difficult. Furthermore, many patients have both conditions. This study assessed changes in ventricular function during rest and exercise in patients with mitral valve prolapse alone and in patients with prolapse and concomitant coronary artery disease. Twelve patients with angiographically documented mitral valve prolapse and normal coronary anatomy and 11 patients with normal coronary anatomy and no mitral valve prolapse had increased ejection fraction and demonstrated no wall motion abnormality during exercise. Changes in ventricular function during exercise in 11 additional patients with mitral valve prolapse demonstrated on echocardiography were similar to those in the group with mitral valve prolapse and normal coronary anatomy seen on angiography. In contrast, 6 of 11 patients with mitral valve prolapse and coronary arterial stenosis demonstrated on angiography had a decreased ejection fraction and exhibited wall motion abnormalities during exercise. These results suggest that mitral valve prolapse alone has no detrimental effect on ventricular function during rest and exercise and that exercise-induced abnormalities in ventricular function are related to the presence and severity of coronary artery disease and not to mitral valve prolapse.

Adult↗

Interpretation of cardiac pathophysiology from pressure waveform analysis: mitral valve gradients: Part II.

Balloon mitral commissurotomy in many patients will be as satisfactory as closed surgical commissurotomy. Data from combined hemodynamic and echocardiographic techniques elegantly elucidate the mechanisms of mitral valve flow and pathophysiology of disturbed pressure relationships between the left atrial and left ventricular chambers, both before and after balloon valvuloplasty. The pulmonary capillary wedge pressure may not be satisfactory to assess the success of gradient reduction after mitral valvuloplasty.

Adult↗

Congenital mitral valve anomalies in transposition of the great arteries.

In 165 hearts in transposition of the great arteries, including 16 with a ventricular septal defect and overriding pulmonary trunk and 5 with a so-called posterior transposition, the left ventricle was studied with emphasis on the morphology of the mitral valve. Distinct mitral valve anomalies were found in 36 cases (22 percent), and four categories of anomalies could be identified. Group A included 16 specimens with a cleft anterior mitral valve leaflet. The cleft was complete or partial. Partial clefts continued as a fibrous cord within the leaflet. In eight cases the cleft was situated posterior or lateral to the pulmonary ostium; in these cases the left ventricular outflow tract was not narrowed. Severe outflow tract stenosis was present in another eight cases in which the cleft was located anterior to the pulmonary ostium, usually in combination with a ventricular septal defect, and in four of these specimens there was straddling of the mitral valve. Group B included eight hearts with an abnormal size or position of the mitral valve, or both, the valve being hypoplastic or rotated clockwise, or both. Group C comprised seven hearts showing redundant left ventricular structures involving the mitral valve, among which were anomalous tissue strands, subpulmonary rings and redundant valve tissue. Group D included five specimens with deficient papillary muscles. It is concluded that an abnormal mitral valve is not unusual in hearts with transposition of the great arteries. The findings are notably important for those patients for whom anatomic surgical correction of the transposition is considered. In comparison with the venous baffle procedure, this operation makes greater demands on the structure of the mitral valve because the pressure in the left ventricle remains at systemic level. Thorough investigation of mitral valve anatomy and function is necessary before anatomic correction is considered.

Adolescent↗

Surgical repair for mitral valve disease.

The concept of mitral valve repair is discussed emphasizing the basic knowledge on which it relies. Analysis of the valve disease, characterization of valvular dysfunction and surgical techniques adapted to the most frequent valvular dysfunctions are discussed and illustrated.

Cardiac Surgical Procedures↗

A family study of anterior mitral leaflet thickness and mitral valve prolapse.

To determine whether mitral valve prolapse (MVP) with or without mitral leaflet thickening (> or =5 mm) represents distinct heritable conditions, 13 patients with MVP with leaflet thickening and their relatives were compared with 67 patients with MVP with normal leaflets and their relatives. The 2 groups of relatives had similar mitral leaflet thicknesses and similar long-term outcome, arguing against the existence of a distinctive subtype of MVP characterized by increased mitral leaflet thickness.

Adult↗

Mitral valve surgery: reconstruction versus replacement.

The debate between reconstructive versus replacement operations for the diseased mitral valve has taken on new importance as the late results for survival, thromboembolic phenomena and incidence of reoperation from a variety of prosthetic and bioprosthetic cardiac valves have now become available. Three series of patients at the Brigham and Women's Hospital from 1972-84, representing 120 patients undergoing open mitral valve reconstruction for mitral stenosis, 348 patients undergoing mitral valve replacement for mitral stenosis, and 363 patients undergoing mitral valve replacement for mitral valve regurgitation are presented. The operative mortality in the reconstruction group was 0, there were 5 late deaths, all non-cardiac, 9 patients had a thromboembolism (1.8%/pt year), and 9 patients required reoperation (1.7%/pt year). For those who had mitral valve replacement for mitral stenosis the operative mortality was 10%, 6% for isolated replacement, 20% if this included a coronary artery bypass. At 9 years the long-term survival was 68 +/- 4%, freedom from thromboembolism 80 +/- 4%, and freedom from valve dysfunction 87 +/- 4%. In the replacement group for mitral regurgitation operative mortality was 11%, 20% with coronary artery bypass. Operative survival was 53 +/- 5% at 9 years, freedom from thromboembolism was 87 +/- 3%, and freedom from valve dysfunction was 91 +/- 4%.

Adult↗

[Mitral valve prolapse: a benign abnormality?].

Mitral valve prolapse should be considered a benign condition as there are few complications. The natural history is not significantly different to that of a matched control population. There are potentially severe forms of the condition which are mainly observed in specialised centres and this introduces a bias in patient selection when compared with the general population. These forms are relatively rare in clinical practice and can be easily identified by simple echocardiographic criteria of valvular thickness. In any case, patients with mitral valve prolapse should be reassured in order not to create or unduly increase anxiety which in itself may cause incapacity.

Arrhythmias, Cardiac↗

Clinical significance of the echocardiographic degree of mitral valve prolapse.

To assess the clinical significance of the echocardiographic degree of mitral valve prolapse, we prospectively evaluated with Doppler echocardiography 245 consecutive patients referred with signs or symptoms consistent with a diagnosis of mitral valve prolapse. The echocardiographic degree of mitral valve prolapse was measured by a scoring system that incorporates an assessment of mitral systolic displacement from the M-mode as well as the two-dimensional long-axis and apical four-chamber views (range 0 to 9, 0 = no mitral valve prolapse). A structured questionnaire was used to record the frequency and severity of symptoms. Pulsed and continuous-wave Doppler echocardiography were performed to document mitral regurgitation and determine the ratio of peak early to atrial diastolic filling velocities. Patients were grouped according to the degree of mitral valve prolapse; 45 patients had no echocardiographic evidence of mitral valve prolapse. There was no statistically significant relationship between the mitral valve prolapse score and symptoms or left ventricular systolic or diastolic function. There was, however, a strong relationship between the echocardiographic degree of mitral valve prolapse and the presence of significant mitral regurgitation. Patients without echocardiographic evidence of mitral valve prolapse had a 4% incidence of mitral regurgitation, which was not significantly different than that of persons with mild degrees of prolapse (6%). However, the groups with the most marked degree of prolapse (scores of 6, 7, 8, and 9) had a significantly higher incidence of mitral regurgitation (20% and 60% respectively, p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

[Calculation of the mitral valve area with the proximal convergent flow method with Doppler-color in patients with mitral stenosis].

In this study we evaluate prospectively a new color Doppler method for calculating the mitral valve area based on identifying a blue-red aliasing interfase proximal to the orifice, corresponding to the flow convergence region (FCR). This method can be used to calculate areas using the continuity equation. We studied 61 patients with stenosis. The mitral valve area was calculated using pressure half-time (PHT) Doppler method which were compared with values that obtained by the FCR method, according to the following formula. AVM (cm2) = 2 pi r2 x VN/Vmax; where "r" is the FCR radius measured from the orifice to the first color aliasing (blue-red interface); VN is Nyquist velocity and Vmax is the peak flow velocity by continuous wave Doppler. Twenty three patients had pure mitral stenosis and 38 double mitral lesion. Twenty patients were on sinus rhythm while 41 in atrial fibrillation. Calculated mitral valve area using the FCR method correlated well with mitral valve area determined by PHT method at a correlation coefficient of r = 0.96 (y = 0.097 x + 54.9, SEE = 0.10 cm2, p < 0.001). MVA by FCR ranged from 0.4 to 2.5 cm2 (mean = 1.19 cm2). MVA by PHT ranged from 0.42 to 2.48 cm2 (mean = 1.15 cm2). Color Doppler FCR method provides an accurate estimate of effective mitral valve area and may be useful as an alternative to the pressure half-time method. The calculated mitral valve area by the FCR method is not influenced by the presence of mitral regurgitation nor atrial fibrillation.

Adult↗

Contractile behaviour of skinned papillary muscle in mitral valve disease.

The contractile behaviour of Triton-X 100 skinned left ventricular papillary muscle from 19 patients undergoing cardiac surgery for mitral valve stenosis: n = 6, mitral valve incompetence: n = 7, or combined mitral valve disease: n = 6 was analyzed. At supramaximal activation the "vibration induced force clamping technique" was used for isometric analysis of time course and extent of isometric postvibration force recovery. Afterloaded contractions were applied for extrapolation of the maximum shortening velocity at zero load (Vmax). The Calcium sensitivity was analysed by variation of the free EGTA-buffered Calcium concentration at a passive resting force of 2 mN at 26 degrees C. In different types of mitral valve disease the characteristics of isometric force development were unaltered in terms of maximum force development, force per square mm, Calcium sensitivity and the time course of isometric contraction after force clamping. However the capability to shorten as expressed by Vmax was reduced in mitral valve incompetence (3.87 +/- 0.37 ML/s) as compared with mitral valve stenosis (5.29 +/- 0.35 ML/s) or combined mitral valve disease (4.83 +/- 0.51 ML/s). The ratio between the inverse value of Vmax and the time constant of isometric force development after force clamping was significantly different in mitral valve incompetence as compared with other types of mitral valve disease (p < 0.0001). These data argue for the presence of different resistances against shortening in various types of mitral valve disease, due to altered cross-bridge cycling characteristics or to morphological factors.

Adult↗

Computer simulation of human mitral valve mechanics and motion.

The human mitral valve is the left atrio-ventricular valve which is composed of several components including leaflets, chordae tendineae, papillary muscles, and the valve annulus. Any or all of these components may fail and contribute to various valvular diseases including mitral regurgitation and mitral valve prolapse. A computer simulation of mitral valve mechanics and motion was written in BASIC for micro-computers. This program allows valvular geometry and biomechanical parameters to be varied and records time varying motion of the valve and all components during systole including a graphic display of the valve leaflets.

Chordae Tendineae↗

Long-term results of surgery for mitral regurgitation due to mitral valve prolapse: a comparison of valve replacement and annuloplasty.

Patients with mitral regurgitation (MR) due to mitral valve prolapse operated at the Second Department of Surgery, Okayama University Medical School, between 1976 and 1986 were divided into two groups. The first consisted of 20 patients who had mitral valve replacement (MVR) and the second 15 patients who had mitral annuloplasty (MAP). Long-term results of surgery, cardiac function, hemodynamic status, and surgical findings were compared between the two groups. Before surgery, there were no significant differences in patient's clinical status and cardiac function between the two groups. However, after surgery statistically significant differences emerged between the two groups in ejection fraction (EF), cardiac index (CI) and mean circumferential fiber shortening velocity (mVcf). Left ventricular pumping function and myocardial contractile force tended to decrease after surgery in the MVR group and to remain unchanged or even increase in the MAP group indicating that valve preservation procedures should be selected as often as possible for the patients involved in mitral valve prolapse.

Adolescent↗

Mitral valve repair versus replacement.

When considering all the major series comparing the early and late results of mitral valve repair versus prosthetic or bioprosthetic mitral valve replacement, the operative mortality rate is slightly lower for patients undergoing valve reconstruction. Late survival is also superior after valve repair. Although these modest differences may be related to patient selection bias, a lower rate of thromboembolic and endocarditis-related complications and improved LV function remain as rather compelling factors favoring valve repair. The durability of valve repair is comparable to valve replacement in terms of reoperation rate, except in cases of rheumatic valve abnormality (in which reoperation rates are higher after valvuloplasty). Definitive, objective evidence favoring mitral valve repair is lacking given the short period of followup in all studies and absence of controlled, randomized clinical trials. The success of mitral valve reconstruction relies heavily on the experience and technical expertise of the surgeon. The wide variability in observed survival rates, however, is unlikely to be due to differences in surgical skill between experienced groups; it more likely represents the results of differing criteria for mitral valve repair, various followup intervals, and comparisons between distinctly different cohorts. Although a prospective randomized trial would be ideal to compare the results of mitral valve reconstruction versus mitral valve replacement for patients with mitral valve regurgitation, it is unlikely and unrealistic that such a study will ever be conducted. The universal applicability of the results of such a study would also be dubious, given the widely varying extent of surgical expertise with mitral valve repair. Furthermore, not all types of mitral regurgitation are amendable to reconstruction short of using patch techniques (usually autologous pericardium treated with glutaraldehyde) or resorting to artificial chordae (e.g., extensive leaflet destruction from rheumatic changes or infective endocarditis, and substantial anterior leaflet redundancy). In cases in which mitral valve replacement is necessary, preservation of the mitral subvalvular apparatus promises to be an important concept to preserve optimal systolic LV function postoperatively.

Heart Valve Prosthesis↗