Implications of mitral valve prolapse in children with rheumatic mitral regurgitation

A review of outcome following valve surgery for rheumatic heart disease in Australia

Background

Globally, rheumatic heart disease (RHD) remains an important cause of heart disease. In Australia it particularly affects younger Indigenous and older non-Indigenous Australians. Despite its impact there is limited understanding of the factors influencing outcome following surgery for RHD.

Methods

The Australian and New Zealand Society of Cardiac and Thoracic Surgeons Cardiac Surgery Database was analysed to assess outcomes following surgical procedures for RHD and non-RHD valvular disease. The association with demographics, co-morbidities, pre-operative status, valve(s) affected and operative procedure was evaluated.

Results

Outcome of 1384 RHD and 15843 non-RHD valve procedures was analysed. RHD patients had longer ventilation, experienced fewer strokes and had more readmissions to hospital and anticoagulant complications. Mortality following RHD surgery at 30 days was 3.1 % (95 % CI 2.2 – 4.3), 5 years 15.3 % (11.7 – 19.5) and 10 years 25.0 % (10.7 – 44.9). Mortality following non-RHD surgery at 30 days was 4.3 % (95 % CI 3.9 - 4.6), 5 years 17.6 % (16.4 - 18.9) and 10 years 39.4 % (33.0 - 46.1). Factors independently associated with poorer longer term survival following RHD surgery included older age (OR1.03/additional year, 95 % CI 1.01 – 1.05), concomitant diabetes (OR 1.7, 95 % CI 1.1 – 2.5) and chronic kidney disease (1.9, 1.2 – 2.9), longer invasive ventilation time (OR 1.7 if greater than median value, 1.1– 2.9) and prolonged stay in hospital (1.02/additional day, 1.01 – 1.03). Survival in Indigenous Australians was comparable to that seen in non-Indigenous Australians.

Conclusion

In a large prospective cohort study we have demonstrated survival following RHD valve surgery in Australia is comparable to earlier studies. Patients with diabetes and chronic kidney disease, were at particular risk of poorer long-term survival. Unlike earlier studies we did not find pre-existing atrial fibrillation, being an Indigenous Australian or the nature of the underlying valve lesion were independent predictors of survival.

World Heart Federation criteria for echocardiographic diagnosis of rheumatic heart disease--an evidence-based guideline

Over the past 5 years, the advent of echocardiographic screening for rheumatic heart disease (RHD) has revealed a higher RHD burden than previously thought. In light of this global experience, the development of new international echocardiographic guidelines that address the full spectrum of the rheumatic disease process is opportune. Systematic differences in the reporting of and diagnostic approach to RHD exist, reflecting differences in local experience and disease patterns. The World Heart Federation echocardiographic criteria for RHD have, therefore, been developed and are formulated on the basis of the best available evidence. Three categories are defined on the basis of assessment by 2D, continuous-wave, and color-Doppler echocardiography: 'definite RHD', 'borderline RHD', and 'normal'. Four subcategories of 'definite RHD' and three subcategories of 'borderline RHD' exist, to reflect the various disease patterns. The morphological features of RHD and the criteria for pathological mitral and aortic regurgitation are also defined. The criteria are modified for those aged over 20 years on the basis of the available evidence. The standardized criteria aim to permit rapid and consistent identification of individuals with RHD without a clear history of acute rheumatic fever and hence allow enrollment into secondary prophylaxis programs. However, important unanswered questions remain about the importance of subclinical disease (borderline or definite RHD on echocardiography without a clinical pathological murmur), and about the practicalities of implementing screening programs. These standardized criteria will help enable new studies to be designed to evaluate the role of echocardiographic screening in RHD control.

Prevalence of rheumatic heart disease among school-children in Aden, Yemen

BACKGROUND

Rheumatic heart disease (RHD) is an important contributor to cardiovascular disease in children and adults in Yemen. This is the first report to determine the prevalence of RHD among school-children in the city of Aden.

METHODS

A cross-sectional case-finding survey of RHD was conducted in 6000 school-children aged 5-16 years. Echocardiography was undertaken in those with clinical signs of organic heart disease.

RESULTS

The prevalence of RHD was 36·5/1000 school-children, which is one of the highest reported among school echocardiography surveys in the world. RHD was more common in 10-16-year-old students. RHD was diagnosed in more than one member of the families of 53 (24·2%) of the children. Mitral regurgitation (MR) was detected in 49·8%, 26·6% had MR with mitral valve prolapse and 17·8% had combined MR and aortic regurgitation. Fifty-eight children were diagnosed with congenital heart disease (CHD), representing a prevalence of 9·7/1000. The main types of CHD were mitral valve prolapse, patent ductus arteriosus, atrial septal defect, pulmonary stenosis and aortic stenosis. Congenital mitral valve prolapse found in 36 children was three times more common in males than females. Children with RHD were more likely to be from low-income families with poor housing and greater overcrowding (49·3%, 39·3% and 64·8%) than children with CHD (44·8%, 32·8% and 48·3%, respectively).

CONCLUSIONS

The high prevalence of RHD is a major public health problem in Yemen. Urgent screening surveys and an RHD prophylactic programme of appropriate management of group A β-haemolytic streptococcal pharyngotonsilitis are required.

Long term follow-up results of 139 Turkish children and adolescents with rheumatic heart disease

We aimed to evaluate the predictors of the severity of chronic rheumatic valvar disease. The long term follow-up records of 139 patients with chronic rheumatic carditis were reviewed. Children were followed-up on an outpatient basis for a period ranging from 1-16 years (5.0 +/- 3.7 years). Mitral regurgitation either isolated (51%, n=71) or combined with aortic regurgitation (AR) (49%, n=68) was observed in all cases of the initial attack of rheumatic carditis. AR at initial attack of the rheumatic carditis was found to be affected by gender (AR was more associated with males, p = 0.032), combined mitral and aortic regurgitation (CMAR), and presence of MR at initial attack (p = 0.000 and p = 0.012, respectively) with univariate analysis. The effect of CMAR on AR at initial attack was also significant by multivariate analysis (p = 0.000). CMAR, MR, and AR at initial attack had significant effects on CMAR at final evaluation (p = 0.000, p = 0.020, and p = 0.000, respectively) in univariate analysis. Multivariate analysis revealed the significant effects of CMAR and MR at initial attack on CMAR at final evaluation (p = 0.000 and p = 0.005, respectively). Univariate analysis showed that MR and AR at initial attack, and CMAR at final evaluation, had significant effects on MR at final evaluation (p = 0.000, p = 0.029, and p = 0.000, respectively). MR at initial attack and CMAR at final evaluation had significant effects on MR at final evaluation with multivariate analysis (p = 0.001 and p = 0.003, respectively). AR at final evaluation was affected by CMAR and AR at initial attack (p = 0.000 and p = 0.000, respectively), and CMAR and MR at final evaluation (p = 0.000 and p = 0.000, respectively) with both univariate and multivariate analysis. Mitral valve prolapsus was more common in patients with a longer duration (37.5%, 6 out of 16) than those with a shorter duration (11%, 14 out of 123) and the difference was significant (p = 0.020). In conclusion, the initial severity of valve involvement and the presence of CMAR at initial attack were found to be the best predictors for the severity of chronic rheumatic valvar disease in this study.

Rheumatic and nonrheumatic valvular heart disease: epidemiology, management, and prevention in Africa

BACKGROUND

Unlike the Western world, valvular disease ranks among the major cardiovascular afflictions in Africa. Acute rheumatic fever and chronic rheumatic valvular disease in their most virulent form are still commonly encountered and impose a huge burden on limited healthcare resources.

METHODS AND RESULTS

We performed a systematic review of the literature with PubMed using rheumatic fever, rheumatic heart disease, valvular disease, warfarin anticoagulation, and pregnancy as search items. Literature emanating from Africa was emphasized. Epidemiology, current concepts on pathogenesis, and aspects of the medical and surgical management of this disease as seen from an African perspective are presented. The association of pregnancy with mitral stenosis is common and may be fatal if not managed appropriately. A practical approach to these patients is presented to optimize maternal and fetal outcome. Pregnant patients with mechanical valves require careful attention to ensure maternal survival and prevent fetal warfarin embryopathy. Prolonged subcutaneous heparin and frequent monitoring of the partial thromboplastin time are impractical in this setting, and the merits of different anticoagulation regimens are discussed. Congenital submitral aneurysms are a unique cause of mitral regurgitation, with the vast majority of cases originating from sub-Saharan Africa. Although the precise etiology is as yet unclear, the clinical and echocardiographic features are sufficiently characteristic to allow a preoperative diagnosis to be made. Transesophageal echocardiography allows much better definition of the size and anatomic relationships of the aneurysm. Surgical resection can be difficult but is usually curative. Mitral valve prolapse and endocarditis constitute the remaining frequent causes of valvular disease and are discussed briefly.

CONCLUSIONS

The spectrum and presentation of valvular disease in Africa are uniquely different from elsewhere. Together with socioeconomic issues and the HIV pandemic, this fact makes it imperative that further epidemiological and clinical studies be undertaken and guidelines developed that are appropriate to the practice of medicine on the African continent.

Reversible mitral valve prolapse and mitral regurgitation in children with Graves' disease

An association between mitral valve prolapse (MVP) and hyperthyroidism has been described in adults. However, the long-term prognosis when associated with significant mitral regurgitation remains unclear. Three consecutive children with Graves' disease were found to have a loud mitral regurgitation murmur (grade III/VI) and echocardiographic evidence of MVP with moderate mitral regurgitation. The cardiac manifestations included palpitations, exertional dyspnea, and exercise intolerance. The electrocardiograms at presentation were sinus tachycardia in all cases. All had hyperthyroidism and positive thyroid antibodies. Exophthalmos occurred in two and appeared later than the cardiac symptoms in one. The cardiac murmur disappeared in all patients when antithyroid agents controlled the hyperthyroidism. Follow-up echocardiography showed normal in one and MVP with mild mitral regurgitation in two. We conclude that MVP and significant mitral regurgitation can occur in children with hyperthyroidism, especially those with Graves' disease. The prognosis is good after adequate medical control of the hyperthyroidism.

Anterior mitral leaflet prolapse as a primary cause of pure rheumatic mitral insufficiency

BACKGROUND

This study was designed to revise the mechanisms and repair techniques of anterior mitral leaflet prolapse observed during the correction of pure rheumatic mitral regurgitation in children.

METHODS

From March 1993 to May 1998, 36 children suffering from pure rheumatic mitral regurgitation due to anterior leaflet prolapse underwent mitral valve repair. The mean age was 12.5 years (range, 6 to 16 years). Anterior leaflet prolapse was due to chordal elongation in 25 patients (group A), chordal rupture in 6 patients (group B), and retraction of anterior secondary chordae tendineae, creating a V-shaped deformity in the middle of the anterior leaflet, thus moving the free edge of the anterior leaflet away from the coaptation plane, in 5 patients (group C). Chordal shortening, transposition, and resection of anterior secondary chordae tendineae were used to correct anterior leaflet prolapse according to the predominantly responsible mechanism.

RESULTS

All patients were available for clinical follow-up, which ranged from 6 months to 5 years (mean follow-up, 3 years). Echocardiographic studies were obtained until the 3rd postoperative month, and all patients showed significant improvement in their left ventricular and atrial dimensions. There was one late death related to endocarditis. Two patients in group C who had mitral valve repair underwent mitral valve replacement on the 19th and 24th postoperative months, respectively, because of failure of mitral valve repair.

CONCLUSIONS

Mitral valve repair for pure mitral regurgitation due to rheumatic anterior leaflet prolapse can be performed safely for all types of mechanisms. Although the techniques we used provide stable short-term results in each of these groups, midterm results are better in groups A and B, where tissue thickening is less important, recurrences of rheumatic carditis are lower, and the interval between the first rheumatic attack and the surgical procedure is shorter than in group C.

Echocardiographic assessment of mitral stenosis and its associated valvular lesions in 205 patients and lack of association with mitral valve prolapse

To date, the relation between mitral stenosis (MS) and other associated cardiac valvular lesions has been reported by angiography and surgical pathologic study in patients with more advanced disease but has not been studied systematically by two-dimensional echocardiography and Doppler color flow mapping in a large referral population with a broader spectrum of severity. In addition, prior reports have suggested that up to 40% of patients with MS have mitral valve prolapse (MVP); however, because of recent developments in two-dimensional echocardiographic imaging and the definition of MVP, this association must now be reconsidered. The purpose of this study was to explore the association of other valvular lesions with MS and their relation to its severity and in particular to test whether MS is in fact associated with MVP with the frequency reported previously. We reviewed the studies of 205 consecutive patients (aged 61 +/- 14 years; range 26 to 87 years) with MS who were studied from 1992 to 1994 by two-dimensional echocardiography and Doppler color flow mapping to assess valvular stenosis, regurgitation, and MVP in patients with a range of severity of MS (28% mild, 34% moderate, and 38% severe MS based on mitral valve area). MS was associated with at least mild mitral regurgitation in 78% of patients (160/205), and pure MS was correspondingly uncommon (22%). There was an inverse relationship between the severity of MS and the degree of mitral regurgitation (p < 0.001). MS was frequently associated (54% of patients) with significant lesions of other valves, including aortic stenosis (17%), at least moderate aortic regurgitation (8%) and tricuspid regurgitation (38%), and tricuspid stenosis (4%). Tricuspid stenosis was associated with more severe MS (p < 0.01), and tricuspid regurgitation was more common in patients with mixed MS and regurgitation than in those with pure stenosis (60% versus 26% for at least moderate tricuspid regurgitation; p < 0.001). Mitral valve prolapse was present in only one patient (0.5%). Superior systolic bulging of the midportion of the anterior mitral leaflet toward the left atrium (but not superior to the annular hinge points) was seen in 22 patients (11%). Patients with such superior bulging had significantly lower mitral valve scores but a similar degree of mitral regurgitation compared with those without bulging. The majority of patients with MS (78%) have associated mitral regurgitation and significant lesions of the other cardiac valves (54%). The frequency of true MVP associated with chronic MS is much lower than reported previously. This may provide insight into the underlying pathophysiologic process, tending to shorten the chordae tendineae and leaflets to produce stenosis rather than elongate them to produce prolapse.