CONGESTIVE HEART FAILURE.pptx

a brief discussion of CHF in children

1. CONGESTIVE CARDIAC FAILURE Dr.Anjana K S Dept of Pediatrics DMWIMS

2. DEFINITION Congestive heart failure (CHF) refers to a clinical state of systemic and pulmonary congestion resulting from inability of the heart to pump as much blood as required for the adequate metabolism of the body.

3. CHF on First Day of Life. causes Comments Asphyxia Sepsis Hypoglycaemia Hypocalcaemia Systemic arteriovenous fistula Tricuspid regurgitation Neonatal myocarditis Anemia SVT Polycythemia Complete heart block

4. CHF in the First Week of Life C auses Structural abnormalities Hypoplastic left heart syndrome Critical aortic stenosis and pulmonary stenosis Total anomalous pulmonary venous drainage (obstructed) Coarctation of aorta Interrupted aortic arch Patent ductus arteriosus (premature) Heart rate and muscle dysfunction Renal Abnormalities Renal failure Systemic hypertension Endocrine abnormalities

5. CHF Presenting Beyond 2 Weeks of 'Life C auses Structural lesions Obstructive lesions Ventricle septal defect Single ventricle Patent ductus arteriosus Aortopulmonary window Truncus arteriosus LCAPA Dilated cardiomayopathy HCM ASD Unobstructed TAPVC

6. Acquired Causes of CHF in Children Acute rheumatic fever Chronic rheumatic heart disease Infective endocarditis Takayasu's arteritis

7. Cardiac Output is determined by: Preload Afterload Myocardial contractility Heart rate

8. Renin-angiotensin system Renin + Angiotensinogen Angiotensin I Angiotensin II Peripheral Vasoconstriction Afterload Cardiac Output Heart Failure Cardiac Workload Preload Plasma Volume Salt & Water Retention Edema Aldosterone Secretion

9. CLINICAL MANIFESTATIONS Depends in part on the degree of the child’s cardiac reserve. 1.Severe CHF (exhausted the compensatory mechanisms ): symptomatic at rest 2. Mild to Moderate CHF: patients may be comfortable when quiet but are incapable of increasing cardiac output in response to even mild activity without experiencing significant symptoms

10. IN INFANTS Prominent manifestations include Tachypnoeic ( Tachypnea with respiratory rate >60/min in a sleeping neonate is abnormal.) Tachycardia >150/min Heart rates >180/min are abnormal even in the setting of respiratory distress and are suggestive of CHF Feeding difficulties Poor weight gain

11. excessive perspiration, irritability, weak cry noisy, labored respirations intercostal and subcostal retractions, as well as flaring of the alae nasi. An infant with heart failure : takes less volume per feeding, becomes dyspnoeic while sucking perspire profusely

12. Physical Examinations Tachycardia Venous congestion: Right sided-Hepatomegaly Left sided- Tachypnea Ascites Retraction Abdominal pain Nasal flaring Pleural effusion Grunting Jugular venous distention. Rales Pulmon.edema

13. Hepatomegaly of >3 cm below the costal margin is usually present, even in the primarily left sided lesions. Hepatic enlargement regresses quickly in response to therapy and is thus a useful indicator of treatment Cold extremity, low blood pressure, skin mottling are signs of impending shock .

14. IN CHILDREN Fatigue, effort intolerance, anorexia, Dyspnoea, Cough. The elevation in systemic venous pressure may be gauged by clinical assessment of jugular venous pressure and liver enlargement. Orthopnoea and basilar rales are variably present; Oedema is usually discernible in dependent portions of the body, or anasarca may be present Cardiomegaly is invariably noted. A gallop rhythm is common; When ventricular dilation is advanced, the holosystolic murmur of mitral or tricuspid valve regurgitation may be heard.

15. DIAGNOSIS HISTORY Poor feeding of recent oncet Tachypnea worsens during feeding Poor weight gain Sweating on forhead Older pt’s – Shortness of breath ,specially while activity Early fatiguability Puffy eyelids Swollen feets

16. Workup Laboratory testing: CBC : anemia,infection Serum electolytes : 1. Hyponatremia: secondary to water retention 2. Hyperkalemia : renal compromise tissue destruction due to low CO Pulse oximetry: hyperoxia test (fail to raise PaO2 >150 on 100% O2) ABG : Mild CCF - Respi Alkalosis Severe CCF- Metaboloc Acidosis

17. X-RAYS Cardiac enlargement : X-ray cardiothoracic ratio - >60% in the new born >55% in older infants with CHF is the rule Absence of cardiomegaly in a good inspiratory film (with diaphragms near the 10th rib posteriorly) practically excludes CHF except due to a cause like obstructed TAPVC

18. CT Ratio method, > 60% Massive cardiomegaly RA dilation Pulm plethora LV Dialatation

19. ELECTROCARDIOGRAPHY Best for potential cause of heart failure, especially tachyarrhythmias Myocardial inflammatory disease and pericarditis: Low-voltage QRS morphologic characteristics ST-T–wave abnormalities

20. ECHOCARDIOGRAPHY The most commonly used parameter in children is fractional shortening (a single dimensional variable), determined as the difference between end-systolic and end-diastolic diameter divided by end-diastolic diameter. Normal fractional shortening is between approximately 28% and 42%. In adults, the most commonly used parameter is ejection fraction (which uses 2-dimensional data to calculate a 3-dimensional volume) the normal range is 55-65%.

21. MAGNETIC RESONANCE ANGIOGRAPHY useful in : 1.quantifying left and right ventricular functional 2.volume and mass 3.coronary artery anatomy. 4.quantify the regurgitant fraction If valvar regurgitation is present Cardiac Troponin Elevated in: Myocarditis Ischemia after coronary anomaly or cardiomyopathy Sepsis (compromised cardiac perfusion)

22. TISSUE DIAGNOSIS Endomyocardial biopsy - inflammatory disease infectious disease metabolic disease PCR - viral myocarditis Genetic analysis in dilated cardiomyopathy – carnitine deficiency

23. MANAGEMENT IT CONSISTS OF : 1. Elimination of the underlying causes. 2. Treatment of the precipitating causes (e.g. infection, anemia, arrhythmias,fever ) 3. Control of heart failure state.

24. Treatment of underlying causes If surgically feasible – surgical correction of underlying CHD. If hypertension – antihypertensive If arrhythmias or heart block – antiarrhythmic agents or pacemakers. If hypothyroidism – its treatment. Fever – antipyretics. Infection – appropriate antibiotics. If anemia – PCV transfusion to raise HCT 35% or higher.

25. General measures ‘Cardiac chair’ or ‘infant seat’ to keep in semi upright position to relieve respiratory distress. 2.Oxygen(40 %-50%) with humidification for hypoxia . 3.In older children salt restriction to <0.5g/day. 4.If respiratory failure then intubation and positive pressure ventilation. 5.Daily weight measurement in hospitalized patients. 6. For recommending rational exercise restrictions : 7.Adequate calorie and fluid intake to permit appropriate weight gain

26. DRUG THERPY Major classes of drugs used : Diuretics Inotropic agents Afterload reducing agents. Prostaglandin E1

27. Diuretics MOA : These agents interfere with reabsorption of water and sodium by the kidneys, which results in a reduction in circulating blood volume and thereby reduces pulmonary fluid overload and ventricular filling pressure Principle therapeutic agents. But it only reduce preload Do not improve cardiac output or myocardial contractility.

28. Classification: 1.Thiazide diuretics: Chlorothiazide Hydrochlorothiazide 2.Rapid acting loop diuretics - Furosemide Ethacrynic acid 3.Aldosterone antagonists - Spironolactone

29. Rapidly acting inotropic agents ( α- and β- Adrenergic Agonists) INCLUDES : Dopamine Dobutamine Isoproterenol Epinephrine.

30. Dopamine Predominantly β-adrenergic receptor agonist, but it has α-adrenergic effects at higher doses. Dose: 2-10 μg /kg/min (Increased contractility with little peripheral vasoconstrictive effect) 15 μg /kg/min (its peripheral α-adrenergic effects may result in vasoconstriction) Fenoldopam Dopamine da1 receptor agonist Low dose 0.03 μg /kg/min (to increase renal blood flow and urine output) Can cause hypotension, so blood pressure should be carefully monitored.

31. Dobutamine Has direct inotropic effects and causes a moderate reduction in peripheral vascular resistance. Dose : 2-20 μg/kg/min. Isoproterenol Pure β-adrenergic agonist that has a marked chronotropic effect It is most effective in patients with slow heart rates Less commonly used in patients with heart failure with normal or increased heart rates, because of the increased risk of arrhythmias.

32. Epinephrine mixed α- and β-adrenergic receptor agonist. Uses in : cardiogenic shock and low arterial blood pressure. Side effects : increases systemic vascular resistance, increases the afterload increased risk of arrhythmia

33. Digitalis Glycosides MOA: Improves symptoms in infants with pulmonary over circulation. Has parasympathomimmetic action with slowing of heart rate, reducing sinoatrial firing and slowing the AV conduction. Reduces circulating norepinephrine, renin and aldosterone levels. Is a diuretic agent as well. Increase inotropy without increasing myocardial oxygen consumption.

34. Recommended digitalization schedule rapid digitalization Give half the total digitalizing dose immediately and the succeeding 2 one-quarter doses at 12-hr intervals later. The electrocardiogram must be closely monitored and rhythm strips obtained before each of the 3 digitalizing doses .

35. Oral digoxin dosage Iv dose will be 75% of oral dose Age Total Digitalizing dose(µg/kg) Maintenance dose(µg/kg/day) Premature infants 20 5 Newborn infants 30 8 <2Yrs 40-50 10-12 >2Yrs 30-40 8-10

36. Afterload-reducing agents ARTERIOLAR DILATOR : Hydralazine Augments cardiac output. Used with propranolol because it activates baroreceptor reflex with resulting tachycardia. VENODILATORS : Nitroglycerine Isosorbide dinitrate Acts by dilating systemic veins and redistributing blood from pulmonary to systemic circuits. MIXED VASODILATORS : ACE inhibitors Nitroprusside Prazosin

37. Indications Large lt to rt shunt : VSD PDA Left sided regurgitant lesion: AR MR Poor systolic function: Myocarditis Dilated cardiomyopathy

38. Phosphodiesterase inhibitors MILRINONE Use in : patients with low cardiac output who are refractory to standard therapy MOA : inhibition of phosphodiesterase, which prevents the degradation of intracellular cyclic adenosine monophosphate. Milrinone has both positive inotropic effects on the heart and peripheral vasodilatory effects and has generally been used as an adjunct to dopamine or dobutamine therapy in the intensive care unit.

39. Doses : Intravenous infusion : 0.25-1 μg /kg/min Initial loading dose of 50 μg /kg. Side effect : Hypotension secondary to peripheral vasodilation, especially when a loading dose is used. The hypotension can generally be managed by the administration of intravenous fluids to restore adequate intravascular volume.

40. β -Adrenergic Blockers Carvediol – nonselective Metoprolol – selective β blocker. MOA : Acts by counteracting adrenergic overstimulation seen in patients with chronic CHF. They increase left ventricular fractional shortening and ejection fraction.

41. Carnitine Cofactor for transport of long chain fatty acids into mitochondria for oxidation. Improve myocardial function, reduce cardiomegaly and improve muscle weakness. Beneficial in cases of cardiomyopathy. Dose – 50-100 mg/kg/day twice or thrice a day orally.

42. RECENT ADVANCES IN MANAGEMENT OF CCF

43. Levosimendan A calcium sensitizer which has been used in short term treatment of Acute Decompensated Heart Failure. Act as “guardians of cellular integrity” by stabilizing mitochondrial metabolism during ischemia. Actions : Inotropy: Calcium sensitization Cardio protection: Mitochondrial KATP channel activation. Vasodilatation: Sarcolemmal KATP channel activation . D ose : Loading dose of 6-24µg/kg followed by infusion of < 0.4µg/kg/h

44. Nesiritide This recombinant brain natriuretic peptide (BNP) has been approved for i.v. use to relieve dyspnoea and other symptoms in refractory CHF. It enhances salt and water excretion and is a potent vasodilator with profile of action similar to i.v. glyceryl trinitrate Reduces ventricular filling pressure. Additional hemodynamic and symptomatic improvement can be obtained for short periods, but no long term benefits are evident in CHF.

45. CARDIAC RESYNCHRONIZATION THERAPY : Indicated in: heart failure with left ventricular ejection fraction<= 35% ventricular dyssynchrony EXTRACORPOREAL MEMBRANE OXYGENATION (ECMO): It can take on the functions of heart/lung, till a limited time, until the patient recovers from the initial cause of heart failure or may be used as a “bridge” to heart transplant, when ECMO, can continue to support until a heart becomes available, for transplantation

46. Assist Devices A mechanical circulatory support pump may be positioned extracorporeally (outside) the body or intracorporeally (contained within the body). It may be a biventricular assist device (BIVAD),right ventricular assist device (RVAD), or more commonly left ventricular assist device (LVAD). Further these devices are sub stratified into pulsatile and no pulsatile assist devices.

47. Surgical management Considered when medical treatment does not improve CHF caused by CHDs.. Palliative or corrective cardiac surgeries. Cardiac transplantation – in patients with progressively deteriorating cardiomyopathy.

48. Thank you