MAJOR POINTS—CONT’D

In document Pediatric_Cardiology.pdf (Page 124-127)

Acyanotic Congenital Heart Defects

MAJOR POINTS—CONT’D

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.

MAJOR POINTS—CONT’D

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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