Lecture- 13. Congestive Cardiac Failure in Children

Congestive Cardiac Failure in Children

1. Lecture-13 CONGESTIVE CARDIAC FAILURE IN CHILDREN Prof. Dr. Sunil Natha Mhaske Dean Dr. Vithalrao Vikhe Patil Foundation’s Medical College and Hospital, Ahmednagar (M.S.) India-414111 Mo- 7588024773 [email protected]

2. Definition- Clinical syndrome in which the heart is unable to pump enough blood to the body to meet its needs, to dispose of venous return adequately or a combination of the two. Childs heart does not pump enough blood out to the rest of the body to meet the body's demand for energy.

3. Causes- Congenital Heart disease- VSD PDA Endocardial Cushion defect Hypoplastic left heart syndrome TGA Acquired Heart Disease- Metabolic abnormalities Viral Myocarditis Acute Rheumatic Carditis Rheumatic Valvular heart diseases – MR, AR Dilated Cardiomyopathy

4. Miscellaneous- Supraventricular Tachycardia Complete Heart block Severe Anemia Acute Hypertension Bronchopulmonary dysplasia Acute cor pulmonale

5. Time of Onset of CCF in Congenital lesions Age Lesion Birth to 72 hrs Pulmonary, mitral and aortic atresias or critical stenosis 4 days to 1 week Hypoplastic left and right heart syndromes, transposition and malposition of great arteries with poor mixing 1 to 4 weeks Transposition and malposition complexes, endocardial fibroelastosis , coarctation of aorta 1 – 2 months Transposition and malposition complexes, endocardial cushion defects, VSD, PDA, TAPVC, ALCAPA 2 to 6 months Transposition and malposition complexes, VSD, PDA, TAPVC, Aortic stenosis, Coarctation of Aorta

6. Clinical features- Poor growth very sweaty with feedings Difficulty breathing Sleep more or have less energy Faster breathing and heart rate Small and wasted appearance Difficulty eating liver may also be enlarged Puffiness of the eyes or feet as the right heart fails. Delays in reaching developmental milestones Chest pain Dizziness Palpitations Syncope Tachycardia Gallop rhythm Weak thready pulse

7. Ross scoring system for heart failure in infants

8. Diagnosis Physical examination Electrocardiogram- sinus tachycardia, LV hypertrophy, ST-T changes, myocardial infarction patterns, and conduction blocks. Chest X-ray A graded exercise test Echocardiogram Cardiac catheterization Cardiac MRI Biomarkers - natriuretic peptides (brain natriuretic peptide [BNP] - amino terminal [NT]- proBNP )

9. Blood glucose Serum electrolytes like calcium, phosphorous Screening for sepsis Antistreptolysin O and C-reactive protein measurement Metabolic and genetic testing Endomyocardial biopsy

10. Treatment Underlying cause should be identified and treated. Large left to right shunts- prompt surgical therapy A precipitating causes like intercurrent infections, anemia, electrolyte imbalances, arrhythmia, rheumatic reactivation, infective endocarditis, drug interactions, drug toxicity, or drug noncompliance should be identified and corrected if present. Indiscriminate administration of intravenous fluid resuscitation is contra-indicated and will worsen the condition of children with HF. In acute decompensation general measures such as bed rest, propped up position, humidified oxygen sodium, and if required, volume restriction are followed routinely. Infants with CHF require 120–150 Kcal/kg/day of caloric intake and 2–3 mEq /kg/day of sodium . Iron supplementation Salt restricted diet

11. Drug therapy Drug therapy is aimed at reducing the pulmonary or systemic congestion by the use of diuretics, increasing contractility by inotropes, and reducing the disproportionately elevated afterload by vasodilators and other measures. Routinely used drugs in the management of cardiac failure in children include diuretics, digoxin, angiotensin-converting enzyme inhibitors (ACEIs), spironolactone, beta-blockers, and inotropes. The drugs which are still investigational include natriuretic peptides, vasopressin antagonists, renin inhibitors, endothelin antagonists, oral phosphodiesterase inhibitors, anti-inflammatory molecules, nitric oxide agonists, and neuropeptidase antagonists, etc.

12. Diuretics first line agents to reduce systemic and pulmonary congestion. Loop diuretics have been the most widely used. Frusemide is given intravenously at a dose of 1–2 mg/kg or 1–2 mg/h infusion. For chronic use 1–4 mg/kg of frusemide or 20–40 mg/kg of chlorothiazide in divided doses are used. Patients who are unresponsive to loop diuretic agents alone might benefit from the addition of a thiazide agent like metolazone . Continuous infusion of diuretics is recommended in cases of acute decompensated HF. Diuretic-induced hypokalemia and hypontremia are rare in children. Secondary hyperaldosteronism does occur in children so add spironolactone 1 mg/kg single dose to conserves potassium.

13. Digoxin Digoxin has a very narrow safety window and it should be avoided in premature babies, those with renal failure and those with acute myocarditis. Electrolyte imbalance like hypokalemia and hypomagnesemia should be promptly corrected to avoid potentiation of toxicity and development of arrhythmias. Rapid digitalization is generally not required. In most circumstances, starting with an oral maintenance dose (8–10 µg/kg/day) with no loading dose is adequate. Dose reduction is required in HF patients on carvedilol and amiodarone targeting lower serum digoxin concentrations (e.g., 0.5–0.9 ng/ml).

14. Dose: Preterm – 10 – 20mcg/kg P.O Term – 20 – 30 mcg/kg P.O 1 – 5 years – 30 -40 mcg/kg P.O 5 – 10 – 20 – 30 mcg/kg P.O Adults – 10 – 15 mcg/kg P.O IV is 80% of P.O dose Contra indication – WPW syndrome with AF Significant AV nodal block Diastolic dysfunction Relative Contraindication – low output states – Valvular stenosis High output states – Chronic corpulmonale and thyrotoxicosis Hypokalemia Chronic lung disease Myxedema Acute hypoxemia Renal failure Co - therapy with drugs altering digoxine levels or causing AV inhibition Severe myocarditis

15. Angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers For the treatment of symptomatic LV dysfunction in children, ACEIs are routinely used unless contra-indicated. In children with cardiac failure, the ACEIs which have been most studied are captopril and enalapril Captopril is preferred in neonates (0.4–1.6 mg/kg/day in 3 divided doses) and infants (0.5–4 mg/kg/day in three divided doses). Enalapril is the first choice for those older than 2 years of age (0.1–0.5 mg/kg/day in two divided doses). Children treated with ACEIs should be watched for deterioration in renal function and hypotension, cough and angioedema.

16. Aldosterone antagonists The literature supporting the role of spironolactone in Paediatrics HF is however limited. Aldosterone antagonist therapy is reasonable in children with chronic systolic HF. It is contra-indicated in patients with renal dysfunction and hyperkalemia. Spironolactone is used most often in children because experience with eplerenone in children is limited. Usual starting dose of spironolactone is 1 mg/kg/day and the target maximum dose is 2 mg/kg/day. Male gynecomastia can occur with spironolactone requiring replacement with eplerenone . Monitoring of renal function and serum potassium is required when coadministered with ACEIs.

17. Beta-blockers The benefits of beta-blocking agents in children has not yet proven conclusive. Carvedilol is started at 0.05 mg/kg/dose (twice daily) and increased to 0.4–0.5 mg/kg/dose (twice daily) by doubling the dose every 2 weeks. Metoprolol (0.1–0.2 mg/kg/dose twice daily and increased to 1 mg/kg/dose twice daily) or bisoprolol may be used as an alternative to carvedilol. Beta-blockers should not be administered in acute decompensated HF. Therapy should be started at a small dose and slowly up-titrated.

18. Inotropes C ommon are the catecholaminergic drugs such as dopamine and dobutamine , and the phosphodiesterase inhibitors such as milrinone and amrinone . Catecholaminergic drugs commonly used are dopamine 5–20 mcg/kg/min and dobutamine 5–20 mcg/kg/min. Epinephrine and norepinephrine are associated with arrhythmias and increased myocardial oxygen demand. Milrinone , a phosphodiesterase inhibitor is an inotrope and vasodilator prevents low cardiac output syndrome after cardiac surgery in infants and children. The loading dose of milrinone is 25–50 mcg/kg/min and maintenance dose is 0.25–1 mcg/kg/min. Milrinone causes peripheral vasodilation and should be used with caution in hypotensive patients. Levosimendan is another inotrope with vasodilatory property by a calcium-sensitizing effect and opening up of vascular ATP-dependent K + channels. Its use in children are promising.

19. Dopamine- Dose- < 2.5mcg/kg/min - Increase blood flow to cerebral coronary renal and splanchnic vascular bed through DA1 postsynaptic receptor. 2.5-5 mcg/kg/ mt - Inotropic effect through b receptor 5-10 mcg/kg/ mt - Both a and b effects occur. >10 mcg/kg/ mt - Arterial tone progressively increases. Indications- Cardiogenic shock with Hypotension Complication- Tachyarrhytmias Extremity gangrene Increases Pulmonary vascular resistance particularly in hypoxemic pulmonary hypertension and may suppress central respiratory drive

20. Afterload Reduction Sodium Nitroprusside- 0.5 – 10 mcg/kg/min but infusion at maximal rate should never last > 10minutes . Nitroglycerine- IV infusion – 1- 10 mcg/kg/min iondilators Indication : Increased ventricular filling pressure Increased systemic vascular resistance Normal blood pressure or hypertension Systolic BP Neonate >50 mmHg 1 mo to 12 mo >60mmHg 1 to 12 yrs > 70 + (Age x 2 )

21. Device therapy P acemaker therapy C ardiac resynchronization therapy ( CRT) Mechanical circulatory support. Implantable cardioverter defibrillator (ICD) implantation Extracorporeal membrane oxygenation (ECMO) Cardiac transplantation Heart transplantation remains the therapy of choice for end-stage HF in children refractory to surgical and medical therapy.

22. Conclusion The causes and clinical presentation of HF are different from adults. The overall outcome with HF is better in children than that in adults. There has been a significant advance in the evidence base for the management of HF in adults. general principles of management are similar to those in adults. There is a compelling need for larger and higher quality studies on the treatment of cardiac failure in children to provide a more robust evidence base.

23. Thanks a lot