Acyanotic Congenital Heart Defects
● Cardiomyopathy accounts for only 1% of all pediatric cardiac disease.
● DCM is the most common myocardial disease in childhood (0.4–8.0 cases per 100,000 people, with a prevalence of 36 cases per 100,000 people).
● The hallmark of DCM is systolic dysfunction.
● In children, the etiology of the majority of cases of DCM remains unidentified or idiopathic.
● There are multiple patterns of inheritance in familial DCM, with autosomal dominant being the most common; six genes have been localized.
● In infants with DCM, failure to thrive is often a chief complaint. In older patients, the initial presenting symptom is respiratory distress, secondary to pulmonary edema from congestive heart failure.
● The main goals of treatment for patients with DCM are supportive therapy to improve cardiac function and prevention of complications such as thromboembolic events and significant arrhythmias.
● The prevalence of HCM is estimated to be 10–100 cases per 100,000 people.
● The onset of symptoms usually occurs in early adulthood for most patients with HCM.
● The most severe complication of HCM is sudden death.
The incidence of sudden death has been reported at between 4–6% in children and 1–4% in adults.
● The clinical manifestations of HCM can be explained by diastolic dysfunction, outflow tract obstruction, and mitral regurgitation.
● Over 90% of reported cases of HCM are considered to be inherited.
● Some noncardiac syndromes associated with HCM are Noonan’s, Beckwith-Wiedemann, Hurler’s, Hunter’s, as well as Fabry’s and Pompe’s diseases.
● The primary aim in treating HCM is improving ventricular compliance and minimizing the risk of life-threatening arrhythmias and sudden death.
● Amiodarone is considered the drug of choice in the treatment of ventricular ectopy and nonsustained ventricular tachycardia in this patient population.
● Most cases of RCM are idiopathic.
● The restrictive physiology is classically characterized by four hemodynamic findings: normal systolic function, equalization of the right ventricular and left ventricular end-diastolic pressures, an increase in mean atrial and ventricular end-diastolic pressures, and a dip-plateau pattern of ventricular filling.
● The mainstay of medical therapy for patients with restrictive cardiomyopathy is symptomatic treatment.
● Noncompaction or spongiform cardiomyopathy is thought to be due to persistence of embryonal myocardial tissue, represented by a loosely interwoven mesh of immature myocytes.
● Cardiac transplantation may be the treatment of choice for many patients with progressive or end-stage cardiomyopathic disease.
● The working etiologic hypothesis favors that
myocarditis develops in response to some stimulation that causes the immune system to overexpress components, resulting in inflammation and myocyte damage.
● The immunologic component of myocarditis has guided the treatment regimen to include
immunosuppression and anti-inflammatory agents.
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