Andersons pediatric cardiology 1655

Electrocardiography The ECG findings in DCM are nonspecific and may be normal (Fig 61.9) Patients with heart failure typically present with sinus tachycardia, and there may be atrial or ventricular hypertrophy and/or ectopy Q waves may be present in situations where there is focal myocardial fibrosis Deep Q waves in leads I and aVL raise the possibility of anomalous origin of the left coronary artery from the pulmonary artery The presence of conduction disease raises suspicion of SCN5A and LMNA mutations in addition to myocarditis FIG 61.9 12-lead electrocardiogram from a 2-year-old with familial idiopathic dilated cardiomyopathy shows nonspecific ST-segment and Twave abnormalities Chest Radiograph The chest radiograph typically shows cardiomegaly with evidence of pulmonary edema with or without effusions In cases of acute myocarditis or early cardiotoxic therapy-induced disease, the cardiac size may be relatively small and dilation will evolve with time Echocardiography The diagnosis is typically made by echocardiography based on the presence of left ventricular dilation (z-score greater than +2) and systolic dysfunction (Fig 61.10) Right ventricular dysfunction and dilation may coexist with LV systolic dysfunction The degree of left ventricular dilation and severity of systolic dysfunction are associated with worse prognosis in pediatric DCM.295–298 Threedimensional echocardiography is increasingly being used to quantify left ventricular indices and function given that it appears to be more accurate and reproducible than M-mode and two-dimensional measurement.299 Regional wall motion abnormalities may be present in the setting of focal fibrosis or coronary anomalies Echocardiography should also be used to assess for evidence of atrial or ventricular thrombus.300 FIG 61.10 Echocardiographic features of dilated cardiomyopathy (A) Apical four-chamber view from a 15-month-old with dilated cardiomyopathy, dilated left ventricular cavity with thin walls (B) Parasternal long-axis view, again showing a dilated, thin-walled left ventricle from the same patient Abnormal ventricular filling patterns and evidence of diastolic dysfunction are common in patients with DCM and may predict disease progression.295,301 Doppler evaluation of the tricuspid and pulmonary valves should be performed to evaluate for evidence of elevated pulmonary artery pressures Cardiac Magnetic Resonance Imaging CMRI has been used to assess for the presence of myocardial fibrosis in patients with DCM The presence of late gadolinium enhancement LGE on CMRI is associated with a worse prognosis in adult nonischemic DCM.302 Children and adolescents with DCM rarely have myocardial fibrosis in the absence of myocarditis, and the prognostic value of LGE remains unclear to date.303 The differences in the frequency of LGE may be a reflection of the age-dependent phenotype, and T1 mapping may provide a better measure of adverse myocardial remodeling.304 The prognostic role of CMRI in dystrophinopathy is more established.305,306 Cardiac Catheterization Cardiac catheterization may be used for invasive hemodynamic assessment as well as histologic evaluation in cases of diagnostic uncertainty However, noninvasive assessment of pulmonary artery pressures and myocardial tissue characterization by CMRI have largely supplanted catheterization in the evaluation of DCM Cardiopulmonary Exercise Testing Cardiopulmonary exercise testing is feasible in developmentally appropriate children and may have a prognostic role Lower peak oxygen uptake, in particular, portends a worse outcome.307,308 Management Consensus management guidelines are generally lacking in pediatric DCM The ... The degree of left ventricular dilation and severity of systolic dysfunction are associated with worse prognosis in pediatric DCM.295–298 Threedimensional echocardiography is increasingly being used to quantify left... particular, portends a worse outcome.307,308 Management Consensus management guidelines are generally lacking in pediatric DCM The