Preoperative left ventricular end systolic dimension as a predictor of postoperative ventricular dysfunction in children with mitral regurgitation

Mitral Regurgitation and Serum N-Terminal Pro-Brain Natriuretic Peptide Levels in Children: A Modification of Adult Criteria

Mitral regurgitation can result from congenital heart disease, rheumatic valve disease, or other congenital malformations of the mitral valve. Faulty valves require surgical repair or replacement. However, echocardiographic and biochemical parameters that inform surgical decision-making for adults may not be appropriate for children. To investigate whether adult parameters can be used in children, we correlated echocardiographic parameters with serum N-terminal pro-brain natriuretic peptide (NT-proBNP) levels in children with chronic mitral regurgitation. Our sample comprised 45 patients and 38 healthy children. M-mode measurements, left atrial and left ventricular volumes, and Doppler and tissue Doppler echocardiograms were collected. We graded mitral regurgitation according to European Association of Echocardiography recommendations and indexed effective regurgitant area, vena contracta, and regurgitant volume to body surface area. Patients were grouped by regurgitation severity (mild vs moderate or severe) and left ventricular end-systolic dimension (normal vs enlarged). The NT-proBNP level was higher in patients than in controls (P=0.003), higher in patients with moderate or severe regurgitation (P=0.02), and higher in patients with an enlarged left ventricle (P=0.003). Serum NT-proBNP levels correlated with effective regurgitant area (r=0.47; P=0.002), vena contracta width (r=0.46; P=0.003), regurgitant volume (r=0.32; P=0.04), left ventricular end-systolic diameter (r=0.58; P <0.001), and left atrial diameter (r=0.62; P <0.001). An NT-proBNP value of 66 pg/mL differentiated the mild regurgitation group from the moderate or severe regurgitation group. Our results correlating NT-proBNP and echocardiographic parameters indexed to body surface area indicate that these adult criteria can be used in children to grade mitral regurgitation and inform surgical decision-making.

Cardiopulmonary Resuscitation in Infants and Children With Cardiac Disease: A Scientific Statement From the American Heart Association

Cardiac arrest occurs at a higher rate in children with heart disease than in healthy children. Pediatric basic life support and advanced life support guidelines focus on delivering high-quality resuscitation in children with normal hearts. The complexity and variability in pediatric heart disease pose unique challenges during resuscitation. A writing group appointed by the American Heart Association reviewed the literature addressing resuscitation in children with heart disease. MEDLINE and Google Scholar databases were searched from 1966 to 2015, cross-referencing pediatric heart disease with pertinent resuscitation search terms. The American College of Cardiology/American Heart Association classification of recommendations and levels of evidence for practice guidelines were used. The recommendations in this statement concur with the critical components of the 2015 American Heart Association pediatric basic life support and pediatric advanced life support guidelines and are meant to serve as a resuscitation supplement. This statement is meant for caregivers of children with heart disease in the prehospital and in-hospital settings. Understanding the anatomy and physiology of the high-risk pediatric cardiac population will promote early recognition and treatment of decompensation to prevent cardiac arrest, increase survival from cardiac arrest by providing high-quality resuscitations, and improve outcomes with postresuscitation care.

Aortic and Mitral Valve Disease and Left Ventricular Dysfunction in Children

OBJECTIVES

In this review, we will discuss aortic stenosis, aortic regurgitation, mitral regurgitation, and mitral stenosis. We will review the etiology, anatomy, pathophysiology, presentation, and treatment of aortic and mitral valve disease. Age and lesion specific treatments are outlined based on the severity of valve disease with an aim at long-term preservation of left ventricular function.

DATA SOURCE

MEDLINE and PubMed.

CONCLUSIONS

Mitral and aortic valve disease leads to unique hemodynamic burdens that can impact left ventricular function, quality of life, and longevity. The primary challenge in the management of mitral and aortic valve disease is to apply appropriate medical management and identify that point in time at which the surgery is necessary. Although guidelines have been established for the management of aortic and mitral valve disease in adults, the challenges of early presentation, maintenance of growth potential, and apparent increased tolerance of hemodynamic burden in children makes decision making challenging.

Evaluation of Acquired Valvular Heart Disease by the Pediatrician: When to Follow, When to Refer for Intervention? Part I

Lesions of the heart valves are the commonest acquired cardiac abnormalities seen in pediatric age group. In India, the underlying cause for most valvular diseases is chronic rheumatic heart disease (RHD). The aim of evaluation of patients with valvular heart disease is not only to make a diagnosis, but also to decide the management plan. The pediatrician or physician is usually the first health care provider to whom such patients (or their parents) report. It is therefore imperative that the general physician and pediatricians are well versed with valvular heart diseases. Valvular abnormalities produce characteristic murmurs and a bedside diagnosis is possible in majority. However, further investigations such as X ray of the chest and an ECG are useful tools to refine the diagnosis. Echocardiography is now widely available to most of the patients in India and is very useful for assessing the severity of valve lesion and to identify the underlying etiology. Serial echocardiography is instrumental in deciding the timing of intervention. Mitral valve is most commonly affected followed by aortic; in some patients both valves may be affected. The valve may not close properly, resulting in regurgitation of blood flow in reverse direction or does not open fully (stenosis). In mitral regurgitation (MR), the blood flows in the reverse direction. MR can occur secondary to several causes, but in India, the commonest cause is RHD. Patient may remain asymptpmatic for a long period of time. Symptoms include fatigue, palpitations and later exertional breathlessness. MR typically produces a pansystolic murmur at apex, which may radiate to left axilla. Surgical intervention is reserved for all symptomatic patients with severe MR. Valve repair is preferred over prosthetic valve replacement. Mitral stenosis (MS) is almost always due to RHD. Severe MS results in pulmonary hypertension, right ventricular failure and tricuspid regurgitation. Patients are often symptomatic with dyspnea. Hemoptysis may occur. A typical rumbling mid diastolic murmur is the hallmark of MS. Balloon mitral valvotomy, performed in the catheterization lab, is recommended for severe MS.

Indications for intervention in asymptomatic children with chronic mitral regurgitation

Based on outcome data, surgery is recommended for asymptomatic adults with chronic mitral regurgitation (MR) and systolic dysfunction, marked left ventricular (LV) dilation, pulmonary hypertension, atrial fibrillation, or high likelihood of successful repair; but indications for children are poorly defined. We sought to determine predictors of postoperative LV dysfunction in asymptomatic children with chronic MR. The surgical database was searched for all children who underwent mitral valve surgery for chronic MR (2000-2012). Exclusion criteria were preoperative symptoms, acute MR, cardiomyopathy, or other defects affecting LV size. Preoperative and latest follow-up clinical and echocardiographic data were obtained. LV dysfunction was defined as ejection fraction (EF) ≤55% or shortening fraction (SF) ≤28%. Associations between preoperative factors and late LV dysfunction were determined using univariate Poisson regression. For the 25 children who met criteria, preoperative median LV end systolic Z score (LVESZ) was 5.3, EF was 65%, and SF was 34%. At follow-up (median 3.9 years), nine patients (36%) had LV dysfunction. Lower preoperative SF (OR 0.6, p < 0.001) and higher LVESZ (OR 1.7, p < 0.01) were associated with late LV dysfunction. LVESZ ≥ 5 combined with SF ≤ 33% had a sensitivity of 89%, specificity of 88%, and negative predictive value of 93% for late LV dysfunction. Only 1/14 patients with preoperative SF > 33% had late LV dysfunction. For asymptomatic children with chronic MR, surgery should be considered before LVESZ exceeds five and SF falls below 33%. Patients with SF > 33% may be followed with serial echocardiographic measurements.

Clinical and functional characterisation of rheumatic mitral regurgitation in children and adolescents including the brain natriuretic peptide

Rheumatic fever is a public health problem of universal distribution, predominantly affecting individuals in developing countries. In individuals less than 20 years of age, pure mitral regurgitation is the most commonly found condition in chronic rheumatic valve disease. In the present study, rheumatic mitral regurgitation was assessed in children and adolescents, addressing its clinical (duration of the disease, symptoms, use of benzathine penicillin, and number of outbreaks of the acute phase of rheumatic fever), electrocardiographic (left atrium abnormality and/or left ventricle hypertrophy) and echocardiographic characteristics (left atrium and ventricle measurements, ejection fraction and pulmonary artery pressure), as well as plasma dose of N-terminal portion of the brain natriuretic peptide through electrochemiluminescence immunoassay. Fifty-three patients were studied. The patients had moderate (41.5%) or severe (58.5%) rheumatic mitral regurgitation; had not undergone surgery; were not in the acute phase of the disease; and were being treated at a paediatric cardiology reference hospital in Northeastern Brazil. Mean patient age was 10.6 years (minimum of 3 and maximum of 19 years). With the exception of the ejection fraction, the echocardiographic variables had a significant correlation to the natriuretic peptide, demonstrating that this hormone reflects the haemodynamic consequences of mitral regurgitation. It was concluded that cardiac remodelling that occurs in rheumatic mitral regurgitation in children and adolescents leads to the production of the brain natriuretic peptide, which could be used as a complementary diagnostic tool in the follow-up of such patients.

Mitral valve prolapse with a late-systolic regurgitant murmur may be associated with significant hemodynamic consequences

The late-systolic murmur of mitral regurgitation (MR) in degenerative mitral valve disease is widely believed to represent regurgitation of a degree that is not associated with hemodynamic significance. However, the extent of left ventricular (LV) remodeling associated with the late-systolic murmur has not been systematically assessed. Accordingly, we studied 82 patients sent for evaluation of at least moderate isolated MR by echocardiography/Doppler examination. All patients had a physical examination and cardiac magnetic resonance imaging to measure LV volumes by summation of serial short-axis slices. Forty-five patients had a pan-systolic murmur and 37 had a late-systolic murmur on auscultation that was verified by timing of onset of regurgitant turbulence by cine magnetic resonance imaging. Systolic blood pressures (124 +/- 3 versus 124 +/- 3 mm Hg) and LV ejection fraction (61 +/- 1% versus 61 +/- 1%) did not differ significantly between pan-systolic and late-systolic murmur groups. Although LV end-diastolic volume index was greater in the pan-systolic versus late-systolic murmur (108 +/- 4 versus 95 +/- 4 mL/m2, P = 0.007), both groups were significantly greater than normals (68 +/- 2 mL/m2, P < 0.0001). However, LV end-systolic volume index (42 +/- 2 versus 38 +/- 2 mL/m2) and LV end-systolic dimension (38 +/- 1 versus 37 +/- 1 mm), critical markers of adverse LV remodeling in isolated MR, did not differ significantly between pan-systolic and late-systolic murmur groups. In conclusion, the late systolic isolated MR murmur may be associated with significant adverse LV remodeling, and should not be considered evidence of hemodynamically unimportant MR.