Mitral Valve Dilatation Research Articles

Mitral annular disjunction and Pickelhaube sign in children with mitral valve prolapse: A prospective cohort study

BackgroundMitral annular disjunction (MAD) and the Pickelhaube sign are identified as risk factors for malignant ventricular arrhythmias (VAs) and sudden cardiac death in adults with mitral valve prolapse (MVP); their prevalence and consequences in children have never been studied. ObjectivesTo determine the proportion of MAD in children with MVP, and its potential link with VAs. MethodsA cohort of 49 consecutive children (mean age 12.8±3.0 years; 33 females) with MVP and comprehensive clinical arrhythmia (24-hour monitoring) and Doppler echocardiographic characterization, including pulsed-wave tissue Doppler (PWTD) of the lateral mitral annulus, was identified. The relationship between clinical and echocardiographic data and presence of VAs was studied. ResultsMAD was common (n=25; 51%). Only five patients had significant VAs (Lown grade>2) characterized by polymorphic premature ventricular contractions or couplets. MAD was not associated with VAs on 24-hour Holter monitoring, but an association was found between VAs and spiked high-velocity midsystolic signal>16cm/s on PWTD (Pickelhaube sign) (P=0.004), myxomatous mitral valve (P=0.004) and left ventricular dilatation (P=0.01). T-wave inversion in inferolateral leads on electrocardiogram was more frequent in patients with versus without the Pickelhaube sign (P=0.03). No difference was found between patients with or without MAD regarding sex, history of palpitation, severity of mitral regurgitation, aortic root diameter and incidence of connective tissue disorders. Myocardial fibrosis was detected in two of three patients who underwent a complementary cardiac magnetic resonance examination. ConclusionsMAD is common in children with MVP; its presence was not associated with significant VAs on 24-hour Holter monitoring, but the Pickelhaube sign and presence of myxomatous mitral valve may help to detect patients prone to significant VAs. Myocardial fibrosis can be detected by cardiac magnetic resonance in children with significant VAs.

Reductive annuloplasty with autopericardium in surgical treatment of mitral insufficiency

BACKGROUND: Despite the widespread usage of all-type rings in the surgical treatment of patients with mitral valve insufficiency (MV) and dilatation of its fibrous annulus, the researches on this topic are in progress.
 AIM: To study the short- and long-term results of narrowing annuloplasty of the MV utilizing an autopericardium strip of calculated length.
 MATERIALS AND METHODS: The study group consisted of 21 patients (average age 60.9 4.3 years, women 23.8 %) with MV insufficiency of non-rheumatic ethiology. The narrowing of the fibrous annulus during valve reconstruction has been performed along with the posterior 2/3 of their circle using interrupted horizontal sutures. With those sutures, an autopericardial strip of the calculated length has been secured to the annulus. The length of the strip has been calculated according to the original method, according to the data obtained during preoperative transesophageal echocardiography. The length of the strip was 2/3 ∙ D (mm), where D the existing length of the anterior leaflet of the MV in the middle portion from the fibrous annulus to the free edge in the zone of the A2 segment. The control group consisted of 38 patients with non-rheumatic MV insufficiency (average age 59.1 3.5 years, women 23.7 %); the strengthening and narrowing of the fibrous annulus have been performed using a strip made from a wicker vascular prosthesis. The length was 55 mm, equal for all the patients. In both groups, in addition to the narrowing of the fibrous annulus, other types of mitral valve-sparing surgery (partial resection of MV leaflets, suture leaflets techniques, their combination) and combined procedures (coronary bypass surgery, left ventricle reconstructions for postinfarction aneurysms) have been also performed.
 RESULTS: In the studied groups, the safety and reliability of the performed restrictive MV annuloplasty procedures have been demonstrated. During the follow-up period up to 8 years (average 3.5 0.7 years), there was no recurrence of significant mitral regurgitation, which would require repeated surgery in both groups. Narrowing annuloplasty of the fibrous annulus of MV with a strip from the autopericardium of an individual calculated length allows to perform a more accurate anatomical correction of the valve compared with the control group. The existing methods of mitral annuloplasty, their advantages and disadvantages are discussed.
 CONCLUSIONS: The proposed method of restrictive annuloplasty of the MV with an autopericardial strip of the calculated length allows to perform a reliable and safe correction of the dilated fibrous annulus in patients with mitral insufficiency during valve-preserving operations.

Znaczenie osi koniuszkowo-mitralnej w trakcie przezskórnej komisurotomii mitralnej

The development of acute severe mitral regurgitation (MR) requiring surgery is one of the most dreaded complications of percutaneous transmitral commissurotomy. We present the case of a 29 year-old female with severe rheumatic mitral stenosis whose mitral valve dilatation was performed using an Accura balloon. Once the balloon catheter had crossed the mitral valve to reach the left ventricle, it was facing away from the apico-mitral axis. It was inflated in distal portion, and mitral valve dilatation was done in the usual fashion. She developed acute severe MR. As it was misaligned with the apico-mitral axis, it caused a chordae rupture of the postero-medial papillary muscle which was identified during surgery. We conclude that a misaligned Accura balloon catheter during balloon inflation can pluck the chordae tendinae and can cause acute severe mitral regurgitation, and therefore can unearth the underlying subvalvular pathology.

Twenty Years of Clinical Experience with Cardiac Myxomas: Diagnosis, Treatment, and Follow Up.

BACKGROUNDCardiac myxomas are the most frequent cardiac tumors. Although histologically benign, in some cases myxomas may be lethal, due to impairment of cardiac dynamics and their thromboembolic potential. The study aimed to assess the clinical presentation of cardiac myxomas and their correlation with echocardiographic features and to describe the perioperative results and long-term outcome of surgically treated patients.METHODSA prospective study of 53 patients with cardiac myxomas who were operated at Hospital Argerich, followed clinically and with echocardiography from 1993 until 2013. All patients underwent echocardiographic studies.RESULTSThe patient's mean age was 53 ± 16 years (62.3% were women). The most common findings were dyspnea followed by embolic events. Most tumors were localized in the left atrium (77.4%), mainly in the fossa ovalis (63%). Mean size of the tumors was 4.76 x 3.50 cm. Tumors were generally mobile (88%) and went beyond the valve plane, causing mild mitral or tricuspid valve obstruction (58%) and dilation of the respective atrial chamber. Patients whose tumors were obstructive had higher pulmonary artery systolic pressures (50 vs 33 mmHg p < 0.01). According to the echocardiographic appearance 67% of tumors had a smooth surface and the remaining 32% had a villous surface. All patients with embolic manifestations had tumors with a villous surface.CONCLUSIONSClinical presentation relates to the ultrasound characteristics of myxomas. Smooth tumors are larger, occur with obstructive symptoms, and benefit from an elective surgery, whereas villous myxomas entailed a high embolic risk and require prompt surgical treatment.

FLNA mutations in surviving males presenting with connective tissue findings: two new case reports and review of the literature

BackgroundMutations in the X-linked gene filamin A (FLNA), encoding the actin-binding protein FLNA, cause a wide spectrum of connective tissue, skeletal, cardiovascular and/or gastrointestinal manifestations. Males are typically more severely affected than females with common pre- or perinatal death.Case presentationWe provide a genotype- and phenotype-oriented literature overview of FLNA hemizygous mutations and report on two live-born male FLNA mutation carriers. Firstly, we identified a de novo, missense mutation (c.238C > G, p.(Leu80Val)) in a five-year old Indian boy who presented with periventricular nodular heterotopia, increased skin laxity, joint hypermobility, mitral valve prolapse with regurgitation and marked facial features (e.g. a flat face, orbital fullness, upslanting palpebral fissures and low-set ears). Secondly, we identified two cis-located FLNA mutations (c.7921C > G, p.(Pro2641Ala); c.7923delC, p.(Tyr2642Thrfs*63)) in a Bosnian patient with Ehlers-Danlos syndrome-like features such as skin translucency and joint hypermobility. This patient also presented with brain anomalies, pectus excavatum, mitral valve prolapse, pulmonary hypertension and dilatation of the pulmonary arteries. He died from heart failure in his second year of life.ConclusionsThese two new cases expand the list of live-born FLNA mutation-positive males with connective tissue disease from eight to ten, contributing to a better knowledge of the genetic and phenotypic spectrum of FLNA-related disease.

Percutaneous transmitral balloon commissurotomy using a single balloon with arteriovenous loop stabilisation: an alternative when there is no Inoue balloon.

SummaryBackgroundThe Inoue balloon technique is the standard technique for mitral valve balloon commissurotomy at this stage. However, the hardware for this technique is expensive and may not always be available in resource-limited settings. ObjectivesThis article reports our experience with percutaneous transmitral balloon commissurotomy using a single balloon (Nucleus) with arteriovenous loop stabilisation.MethodsEleven young patients, aged 12–26 years and weighing 23–48 kg, underwent transmitral balloon commissurotomy using the described technique at our centre from April to May 2014. ResultsMean fluoroscopy time was 22.6 ± 6.4 min (18.5– 30.0). Mean transmitral gradient decreased from 24.1 ± 5.9 (16–35) to 6.6 ± 3.8 (3–14) mmHg, as measured on transoesophageal echocardiography. Mean mitral valve area increased from 0.69 ± 0.13 cm2 (range 0.5–0.9) before dilation to 1.44 ± 0.25 cm2 (1.1–1.9) after dilation (p < 0.001). Mean estimated pulmonary artery systolic pressure decreased from 110.0 ± 35 mmHg (75–170) before dilation to 28.0 ± 14.4 mmHg (range 10–60) after dilation.ConclusionOur modified Nucleus balloon technique for mitral valve dilation in young patients with mitral stenosis is effective and safe. The technique differs from other over-thewire techniques in that it avoids placing stiff wire in the left ventricle. It also offers better balloon stability and control owing to the arteriovenous loop. This technique may be easier for use by paediatric interventionists who might not be familiar with the Inoue balloon technique.

Successful training of self-sufficient interventional paediatric cardiology team in a sub-Saharan setting: a multicentre collaborative model.

Most children in the Third World do not have access to treatment for heart diseases, as the priorities of health care are different from the developed countries. Since 2009, teams supported by the Chain of Hope and Spanish medical volunteers have travelled twice a year to help develop paediatric cardiac services in the Cardiac Center in Ethiopia, undertaking four missions each year. As of December 2012, 296 procedures were performed on 287 patients. The procedures included 128 duct occlusions, 55 pulmonary valve dilations, 25 atrial septal defect closures, 14 mitral valve dilations, and others. The local staff were trained to perform a majority of these cases. Procedural success was achieved in 264 (89.2%). There were three deaths, five device embolisations, and three complications in mitral valve dilation. During the visits, the local staff were trained including one cardiologist, six nurses, and two technicians. The local team performed percutaneous interventions on its own after a couple of years. The goal is also to enable the local team to perform interventions independently. Training of an interventional cardiology team in a sub-Saharan setting is challenging but achievable. It may be difficult for a single centre to commit to sending frequent missions to a developing country to make a meaningful contribution to the training of local teams. In our case, coordination between the teams from the two countries helped to achieve our goals.

Echocardiographic Methods, Quality Review, and Measurement Accuracy in a Randomized Multicenter Clinical Trial of Marfan Syndrome

The Pediatric Heart Network is conducting a large international randomized trial to compare aortic root growth and other cardiovascular outcomes in 608 subjects with Marfan syndrome randomized to receive atenolol or losartan for 3 years. The authors report here the echocardiographic methods and baseline echocardiographic characteristics of the randomized subjects, describe the interobserver agreement of aortic measurements, and identify factors influencing agreement. Individuals aged 6 months to 25 years who met the original Ghent criteria and had body surface area-adjusted maximum aortic root diameter (ROOTmax) Z scores > 3 were eligible for inclusion. The primary outcome measure for the trial is the change over time in ROOTmaxZ score. A detailed echocardiographic protocol was established and implemented across 22 centers, with an extensive training and quality review process. Interobserver agreement for the aortic measurements was excellent, with intraclass correlation coefficients ranging from 0.921 to 0.989. Lower interobserver percentage error in ROOTmax measurements was independently associated (model R(2) = 0.15) with better image quality (P = .002) and later study reading date (P < .001). Echocardiographic characteristics of the randomized subjects did not differ by treatment arm. Subjects with ROOTmaxZ scores ≥ 4.5 (36%) were more likely to have mitral valve prolapse and dilation of the main pulmonary artery and left ventricle, but there were no differences in aortic regurgitation, aortic stiffness indices, mitral regurgitation, or left ventricular function compared with subjects with ROOTmaxZ scores < 4.5. The echocardiographic methodology, training, and quality review process resulted in a robust evaluation of aortic root dimensions, with excellent reproducibility.

Pneumotórax espontâneo – A pista para outro diagnóstico

Marfan syndrome is an autosomal dominant illness of the connective tissue, with typical skeletal, ocular and cardiovascular manifestations. Less frequently, pulmonary involvement occurs, namely spontaneous pneumothorax, which generally is recurrent and occurs in 4–11% of cases.The authors describe a 14-year-old boy, previously healthy, admitted with a unilateral spontaneous pneumothorax, and clinical phenotype of Marfan syndrome. The subsequent investigation led to the diagnosis of mitral valve prolapse and dilatation of the root of aorta. Pneumothorax resolved through active drainage and a computerised tomography scan excluded subpleural blebs. The patient was readmitted two months later with a new spontaneous pneumothorax, with an identical localization. Surgical resection of a newly identified enfisematous bleb and pleurodesis were performed. Two years later he is asymptomatic.We highlight the importance of an early diagnosis of and a multidisciplinary approach to these patients. Monitoring illness progression and prevention of serious complications, namely cardiovascular, are essential.

Pneumotórax espontâneo – A pista para outro diagnóstico

Marfan syndrome is an autosomal dominant illness of the connective tissue, with typical skeletal, ocular and cardiovascular manifestations. Less frequently, pulmonary involvement occurs, namely spontaneous pneumothorax, which generally is recurrent and occurs in 4-11% of cases.The authors describe a 14-year-old boy, previously healthy, admitted with a unilateral spontaneous pneumothorax, and clinical phenotype of Marfan syndrome. The subsequent investigation led to the diagnosis of mitral valve prolapse and dilatation of the root of aorta. Pneumothorax resolved through active drainage and a computerised tomography scan excluded subpleural blebs. The patient was readmitted two months later with a new spontaneous pneumothorax, with an identical localization. Surgical resection of a newly identified enfisematous bleb and pleurodesis were performed. Two years later he is asymptomatic.We highlight the importance of an early diagnosis of and a multidisciplinary approach to these patients. Monitoring illness progression and prevention of serious complications, namely cardiovascular, are essential.Rev Port Pneumol 2008; XIV (5): 699-704

Coronary artery disease is associated with Alzheimer disease neuropathology in APOE4 carriers

Beeri et al. describe an interesting postmortem study of Alzheimer disease (AD) patients and controls.1 We have also investigated coronary atherosclerosis, cardiovascular disease, and cardiac valve pathology in AD subjects and controls.2 The number of autopsies examined in our study was similar to that reported by Beeri et al. We analyzed general systemic autopsy data from 84 neuropathologically confirmed AD patients and from 60 non-AD control patients using a grade of membership model. All cases of AD were Braak stage IV, V, or VI. Consistent with reports from our center3 and others, the late onset AD groups had elevated APOE e4 frequency. However, the late onset AD groups also had frequent mitral and aortic valve dilation, evidence of ventricular pathology, or both. In contrast to the report by Beeri et al., we observed only modest systemic and coronary atherosclerosis in the …

Ventricular remodeling and mitral valve modifications in dilated cardiomyopathy: New insights from anatomic study

Objective: The purpose of this study was to analyze the behavior of the mitral valve ring and the left ventricle in dilated cardiomyopathy. Methods: We analyzed 68 fixed adult human hearts, divided into 48 hearts with dilated cardiomyopathy of ischemic or idiopathic origin and 20 hearts free of pathologic heart conditions. Digital images of the mitral ring perimeter, attachment of the anterior and posterior leaflets, and fibrous and muscular portions were collected. We also measured the internal perimeter of the left ventricle, the distance from the septum to the anterior and posterior papillary muscles, the distance between the papillary muscles, and the extension of interventricular septum. Results: The analysis of the results showed proportional distribution of the ring's fibrous portion (r2 = 0.98) and muscular portion (r2 = 0.99) according to the degree of mitral valve dilation. Linear regression revealed that the perimeters of anterior and posterior leaflet attachments (r2 = 0.96 and r2 = 0.98, respectively) also had a proportional relation. We did not observe proportionality between the degree of dilation of the mitral ring and the left ventricle. It was observed that dilation of the left ventricle takes place globally in its segments. Conclusion: Differently from what was thought, in ischemic or idiopathic dilated cardiomyopathy, dilation of mitral ring is proportional and does not exclusively affect the posterior portion. The degree of left ventricular dilation does not determine the degree of dilation of the mitral ring because they are independent processes. These observations shed new light on the techniques used to correct mitral valve insufficiency in dilated cardiomyopathy.J Thorac Cardiovasc Surg 2002;124:1216-24

Does the intertrigonal distance dilate? Never say never

J Thorac Cardiovasc Surg 2002;124:1078-9

Inoue balloon mitral valvotomy in patients with atrial septal aneurysm

Atrial septal aneurysms (ASA) are not uncommonly detected in patients with rheumatic mitral stenosis and pose problems during transeptal puncture in patients undergoing balloon mitral valvotomy. From a period of August 1995 to May 1998, we performed a total of 680 Inoue Balloon Mitral Valvotomy (IBMV) procedures with ASA noted in 30 patients, 13 of diffuse and 17 localized type. Transesophageal echocardiography (TOE) was used in all patients with suspected aneurysm on transthoracic echo (TTE) for exact three-dimensional delineation of the location and extent of the aneurysm. The localized type of aneurysms were further subcategorized into five types viz. antero-superior and leftwards (6), postero-superior and rightwards (2), antero-inferior and leftwards (2), postero-inferior and rightwards (5), and central (2), depending on their location in the atrial septum. The site for transeptal puncture was decided after this localization and the remainder of the IBMV procedure was as usual. In the set of thirteen patients with diffuse type of atrial septal aneurysms all but one case had a successful transeptal puncture using standard technique except for a somewhat inferior puncture site so as to be perpendicular to the plane of atrial septum and a successful mitral valve dilatation was possible at first attempt. In the set of 17 patients with localized type of aneurysms, all had a successful transeptal puncture except one. In patients with aneurysms localized antero-superiorly and leftwards the septal puncture was done in a slightly inferior location with transeptal needle pointing some what more posterior, i.e. 5 or 6 o’clock position and in patients with aneurysms localized postero-inferiorly the puncture was done more cephalic with needle directed somewhat anterior, i.e. 3–2 o’clock position. In the two patients with Atrial septal aneurysms located postero-superiorly and to the right the puncture was done slightly inferior but with transeptal needle pointing to about 3 or 2 o’clock position and in the single patient with antero-inferior location the puncture was done in slightly higher but with a more posterior directed needle, i.e. 5–6 o’clock position. The two patients with centrally located localized type of aneurysms had successful transeptal puncture with standard needle direction (4 o’clock) but at a slightly inferior location. We conclude that a good localization of atrial septal aneurysms using transesophageal echocardiography and our technique of transeptal puncture leads to a successful outcome in majority of cases undergoing Inoue balloon mitral valvotomy with associated atrial septal aneurysms.

Percutaneous mitral valve dilatation with the Multi-Track System.

We developed the Multi-Track System for percutaneous mitral valvotomy and described the preliminary results in 1995. Here we report the first 100 consecutive cases after the original publication. Two separate balloon catheters are positioned on a single guidewire. The first catheter, with only a distal guidewire lumen, is introduced into the vein and then advanced into the mitral orifice. Subsequently, a rapid exchange balloon catheter running on the same guidewire is inserted and lined up with the first catheter so the two are positioned side by side. Both balloons are then inflated simultaneously. Age of the patients was 31 +/- 12.8 years and weight 50 +/- 14 kg. Valve area increased 0.75 +/- 0.22 cm(2) to 2.00 +/- 0.32 cm(2)and mean left atrial pressure dropped from 27 +/- 8 to 11 +/- 5 mm Hg. One patient had significant mitral insufficiency after dilatation, which did not require surgery. The Multi-Track System is a valid alternative to the existing procedures for the treatment of mitral stenosis and uses simpler and less costly catheters. Cathet. Cardiovasc. Intervent. 48:178-183, 1999.

Mechanisms of cardiac perforation leading to tamponade in balloon mitral valvuloplasty.

Mechanisms of cardiac perforation in 10 cases of cardiac tamponade encountered in a single-center series of 903 balloon mitral valvuloplasty procedures were elucidated by precise localization of the site of perforation at subsequent surgery. These mechanisms were perforation of the aortic root and adjacent right atrium by sliding up of the transseptal set (2), apical tears by straight-tip balloon catheters driven distally during mitral valve dilatation (3), apical perforations by guidewires introduced through catheters wedged in the apex (2), tear of the posterior right atrial wall by dilatation of the track produced by very low septal punctures (2), and right ventricular perforation by a pacing catheter (1). Multivariate analysis showed cardiac perforation to be significantly related to the total experience at the center (inversely) and to patient age (directly). Left ventricular perforation occurred exclusively in patients > 40 yr of age. Understanding these mechanisms has enabled formulation of effective strategies to prevent cardiac perforation.

Multiple-leaflet mitral valve as a rare cause of congenital mitral insufficiency

A rare case of congenital mitral insufficiency characterized by six well-demarcated leaflets of mitral valve and annular dilatation is reported. At operation, the mitral valve was successfully repaired by resection of the posterior median leaflet with subsequent annular plication, closure of unusual valvular tissue divisions, and ring annuloplasty.

Medical management of young patients with the Marfan syndrome

The Marfan syndrome can be associated with high morbidity and reduced survival, primarily from cardiovascular complications. These manifestations include abnormalities of the mitral valve and progressive dilation of the proximal aorta. In recent years medical and surgical advances have dramatically improved the outlook for patients with the Marfan syndrome. Acute medical treatment of the Marfan syndrome usually involves managing complications such as heart failure from severe mitral and/or aortic valve regurgitation. The long term treatment involves the use of β-adrenergic blockade to retard progressive dilation of the aortic root and to prevent dissection. The efficacy of this therapy has been documented in several prospective trials. Echocardiography or magnetic resonance imaging is used to evaluate the size of the aortic root, allowing for frequent non-invasive follow-up. These techniques can also be used to gauge the effectiveness of β-blockade, detect cardiovascular complications, and help to determine the optimal timing for surgical interventions. Composite graft repair of the aortic valve and ascending aorta is a life-saving procedure in patients with the Marfan syndrome with severe dilation of the aortic root. β-adrenergic blockade should be continued after surgery to protect against arterial dilation and dissection elsewhere.

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.

Hemostatic changes induced by percutaneous mitral valvuloplasty

A study was conducted of hemostatic changes in 15 patients with mild-to-moderate rheumatic mitral stenosis who underwent percutaneous mitral balloon valvuloplasty (PMV). The patients were divided into two groups according to the degree of valve dilatation as evaluated by Doppler echocardiography before and 2 to 3 months after therapy: one group (n = 7) with suboptimal valvuloplasty (<0.5 cm2) and one (n = 8) with optimal valvuloplasty (≧0.5 cm2). On the day of echocardiographic evaluation, hemostatic testing of the platelet, coagulation, and fibrinolytic systems was performed. Before PMV there were no differences in the hemodynamic and hemostatic variables between the two groups. No favorable hemostatic changes were achieved by PMV in the suboptimal group. In the optimal group, however, platelet-specific protein levels decreased after PMV; the mean levels of platelet factor 4 and β-thromboglobulin were moderately elevated before and decreased after PMV from 38.5 ± 22.2 to 8.13 ± 5.08 ng/ml (p < 0.01) and from 132.5 ± 78.6 to 38.8 ± 19.5 ng/ml (p < 0.02), respectively. Coagulation and fibrinolytic systems were unchanged in this study. These data indicate that PMV produces favorable hemostatic effects when sufficient mitral valve dilatation is achieved. Analysis of our data also discloses that platelet activation plays an important role in the initial step of thrombus formation in patients with rheumatic mitral stenosis.