Case Rounds

1. Case Rounds Laura Miles March 3 2012

2. 6 month old female • Several day hx of cough and increased work of breathing

3. What do you want to know?

4. Any investigations?

5. CXR

6. Further Testing… • EGC • Evidence of LVH and possible RVH • Inferior T wave inversion • Echo • Globally poor LV function • Dilated and globular LV • SF 11 % and EF 22% • Normal coronaries

7. ???

9. Cardiomyopathy • Classification • Pathophysiology • Causes • Management

10. Classification • Dilated Cardiomyopathy • Hypertrophic Cardiomyopathy • Restrictive Cardiomyopathy

11. Dilated Cardiomyopathy • Dilation and impaired systolic function of left or both ventricles • Most common type of cardiomyopathy in children • Up to 50% • 0.5 - 8 per 100 000 children

12. Presentation • Initial signs and symptoms may be very vague • Irritability • Anorexia • Abdominal pain • Cough (from pulmonary congestion)

13. Presentation • Signs and symptoms of CHF • Poor systolic function • Limited cardiac output • Ventricles enlarge and myocardium hypertrophies in an effort to maintain cardiac output • Enlargement of ventricles increases systolic wall tension in ventricle and increases myocardial oxygen consumption

14. Presentation • Decreased cardiac output decreases renal blood flow • Enhances renin-angiotensin system • Fluid retention (necessary to maintain output) • Stimulation of the sympathetic nervous system  increased heart rate • Valvular regurg – dilation of the valve annulus • Further myocardial oxygen demand

15. Physical Exam • Signs of CHF • Cardiomegaly • Hepatomegaly • Tachycardia • Tachypnea • Decreased arterial pulse pressure • Narrow pulse pressure • Gallop • Murmur (MR)

16. Further Sequelae • Abnormal myocytes  conduction abnormalities • Nonspecific ST and T wave changes • Atrial arrhythmias • Ventricular arrhythmias • Intraventricular thrombus formation  low flow state

17. A HUGE Differential!! • Majority are idiopathic • 20-50% familial • Autosomal dominant is most common • 5-10% are X linked • Small number of autosomal recessive • Mitochondrial • Viral myocarditis

18. A HUGE Differential!! • Neuromuscular • Duchenne’s Muscular Dystrophy • Becker’s Muscular Dystrophy • Later onset and slower progression • Myotonic Dystrophy

19. Other less common causes: • Infectious (excluding viral myocarditis) • Metabolic • Storage diseases • Nutritional deficiencies • Endocrine • Hypo/hyperthyroidism • Pheochromocytoma

20. Other less common causes: • Coronary artery abnormalities • Congenital • Abnormal placement of the right coronary artery between the great vessels • Acquired • Kawasaki’s • Cardiotoxins • Anthracyclines • Doxorubicin • Donorubicin • Can occur anywhere from months after treatment completion to years later

21. Other less common causes: • Connective tissue diseases • Tachyarrhythmias • Familial hypercholesterolemia • HIV associated • Iron overload • Severe Hypertension

22. Treatment • Look for an identifiable cause and treat it! • Majority of patients however have no specific etiology identified

23. Treatment • Afterload reduction  to improve forward failure • Diuretics as needed for symptoms of backward failure • Inotropic agents to improve symptomatic forward failure

24. Treatment • Treatment is supportive • Either the process resolves • The heart improves • Or the heart is transplanted

25. Natural Hx • Extremely variable • Transient dysfunction with complete recovery and minimal symptoms • Rapid progression to cardiogenic shock and death • Anything in between • Most deaths occur within the first 6 months to 2 years after presentation

27. Hypertrophic Cardiomyopathy • Left ventricular disease • Thickening of the ventricular wall • Nondilated

28. Hypertrophic Cardiomyopathy • Can be symmetric or asymmetric • Asymmetric hypertrophy can obscure outflow tract (HOCM – hypertrophic obstructive cardiomyopathy) • Diagnosis is appropriate only after other causes of left ventricular hypertrophy are excluded

29. Causes • Can be divided into: • Primary (genetic mutation) • Secondary • Obstructive congenital heart disease • Inborn error of metabolism

30. Causes • Familial • Most often autosomal dominant • Wide variability in penetrance • Often denovo • Generally worse prognosis with early signs of disease

31. Causes • Transient • Infant of a diabetic mother • Can develop with corticosteroid use in prems • Metabolic • Glycogen storage disease • Pompe

32. Presentation • Up to 50% of cases present asymptomatically • Evaluation of a murmur • Screening due to a family history • Chest pain • Exercise intolerance • Arrhythmia • Near death event

33. Treatment • Supportive • Important to maintain preload and avoid hypovolemia • No role for afterload reduction or inotropic support (systolic function usually ok) • Use of beta blockers, calcium channel blockers • Prevention of sudden death debatable • May reduce symptoms

34. Treatment • Indications for ICD treatment • Family history • Severe hypertrophy • History of ventricular arrhythmia • Near sudden death

36. Restrictive Cardiomyopathy • Restriction of flow into the ventricles • Accounts for less than 5% of cardiomyopathies in children

37. Pathophysiology • Abnormal relaxation of ventricular myocardium • Decreased ventricular compliance • Altered diastolic filling • Increased ventricular end-diastolic pressure • Elevated atrial pressure • Enlargement of atrium

38. Causes • Idiopathic • Systemic disease • Scleroderma • Amyloidosis • Sarcoidosis • Inborn errors of metabolism • Mucopolysaccharidosis • Hypereosinophilia • Radiation • Malignancy • Noncompaction of the left ventricular myocardium

39. Treatment • Medical treatment has limited success • Pay close attention to fluid balance • High atrial pressures required for adequate preload • If atrial pressures too high, may lead to congestion • Difficult to achieve adequate balance • Usually require early consideration for transplant

40. Questions??

41. References