Heart failure is a clinical and pathophysiological syndrome that results from the inability of the heart to function adequately to meet the metabolic demands of the body.
The Indian Academy of Pediatrics (IAP) has released Standard Treatment Guidelines 2022 for Heart Failure in Children. The lead author for these guidelines on Heart Failure in Children is Dr. R Krishna Kumar along with co-author Dr. Neeraj Awasthy and Dr. Debasree Gangopadhyay. The guidelines come Under the Auspices of the IAP Action Plan 2022, and the members of the IAP Standard Treatment Guidelines Committee include Chairperson Remesh Kumar R, IAP Coordinator Vineet Saxena, National Coordinators SS Kamath, Vinod H Ratageri, Member Secretaries Krishna Mohan R, Vishnu Mohan PT, and Members Santanu Deb, Surender Singh Bisht, Prashant Kariya, Narmada Ashok, Pawan Kalyan.
Following are the major recommendations of guidelines:
Classification of Functional Status of Heart Failure:
The modified Ross classification is most widely accepted and used among the many available classifications for pediatric heart failure (Table1).
TABLE 1: Modified Ross classification of heart failure.
Class I
No symptoms/limitations
Class II
Mild tachypnea/sweating during feeds in infants/dyspnoea on exertion in older children but no growth failure
Class III
Significant tachypnea or sweating during feeds/marked dyspnoea on exertion/prolonged feeding time with growth failure
Class IV
Symptoms (tachypnoea, retractions, grunting, and sweating) even at rest with growth failure
Etiology:
The most important step in managing heart failure in a child is to determine the exact cause (Table 2).
TABLE 2: Classification of causes of heart failure as determined by the underlying mechanism.
Category
Selected Specific Conditions
Shunt lesions
Large post-tricuspid shunts (VSD, PDA, AP window)
Selected pre-tricuspid shunts (a small proportion of ASD patients)
Combinations (Shunt lesion + Obstruction; ASD with mitral valve disease)
Mixed Shunts (AV septal defects)
Cyanotic heart disease with increased pulmonary blood flow
Large systemic AV malformations (Vein of Galen malformation)
Right heart pathology
Tricuspid valve disease—severe regurgitation or stenosis
Severe outflow obstruction—severe stenosis involving infundibulum, pulmonary valve, main pulmonary artery , or branch pulmonary arteries
Long-standing severe pulmonary regurgitation with RV dilation and dysfunction
Pulmonary hypertension
Isolate right ventricular dysfunction
Restrictive physiology
Left heart pathology
Mitral valve disease
Aortic valve disease
Outflow obstruction
Systemic hypertension
Left ventricular systolic or diastolic dysfunction
Rhythm disorders
Tachyarrhythmias (e.g., longstanding supraventricular tachycardia)
Bradyarrhythmias (e.g., congenital heart block)
Ischemic
Premature coronary artery disease
Congenital coronary anomaly (ALCAPA)
Postoperative coronary occlusion
Post-Kawasaki disease
Acquired conditions affecting the myocardium
Myocarditis
Drug- or toxin-related (e.g., Cancer chemotherapy, iron overload)
Anemia
Thyrotoxicosis and thyroid deficiency
Intrinsic myopathies
Metabolic
Mitochondrial
Neuromuscular
Familial
Idiopathic
Restrictive heart disease
Constrictive pericarditis
Endomyocardial fibrosis
Idiopathic restrictive cardiomyopathy
(ALCAPA: anomalous coronary artery from a pulmonary artery; AP: Aortopulmonary; ASD: atrial septal defect; PDA: patent ductus arteriosus; VSD: ventricular septal defect)
Diagnostic Approach:
It is essential to identify co-morbidities and differentiate cardiac from noncardiac causes of heart failure. The tests help that guide the diagnosis and management are listed in Table 3.
TABLE 3: Suggested diagnostic work for heart failure (HF).
Tests
Utility
Complete blood count
Identifying sepsis, anemia
Arterial blood gas with lactate
Lactic acidosis—as a marker of tissue perfusion and helps monitor response to treatment; It is also elevated in specific inborn errors of metabolism
Electrolytes and urea, creatinine
Elevated urea and creatinine may indicate decompensated HF or may result from medication side effects. Electrolyte imbalance is a common association between HF and diuretic use. Hypocalcemia can cause ventricular dysfunction leading to HF
Liver function test
Elevated bilirubin, liver enzymes, and prolonged prothrombin time point toward congestive hepatopathy. Hypoalbuminemia points to chronic HF and poor nutrition
Thyroid function test
A thyroid hormone imbalance could be a primary cause or may lead to worsening of symptoms
Brain natriuretic peptide (BNP)
It helps differentiate HF from respiratory disease. Useful in monitoring response to therapy
Cardiac enzymes (troponin I, T, CKMB)
In suspected cases of myocarditis
Viral panel
Suspected viral myocarditis
Chest X-ray
Information on cardiac silhouette, pulmonary vasculature, pulmonary artery dilatation, and associated skeletal abnormalities
ECG
Diagnosis of treatable causes of heart failure such as persistent tachyarrhythmia, ALCAPA, and, hypocalcemia. Other specific causes such as Pompe's disease, and specific forms of cardiac muscle involvement in muscular dystrophy have ECG manifestations.
Echocardiogram
Critically important to accurate diagnosis and tailoring response to therapy
Cardiac CT/MRI
Required whenever echocardiography windows are suboptimal. MRI allows for a comprehensive physiological assessment in addition to anatomic details. CT allows high-resolution images of cardiac and extra-cardiac structures
Cardiac catheterization
Allows therapeutic interventions to manage heart failure. Examples include the closure of shunts and fistulae, balloon dilation of critically narrow valves, balloon dilation, or stenting of vessels. Diagnostic cardiac catheterization
is particularly useful for quantifying pulmonary artery pressure and
identifying the cause of pulmonary hypertension
Six-minute Walk test
Helpful in ascertaining functional status and response to therapy
(ALCAPA: anomalous coronary artery from pulmonary artery)
Management:
The main goals of HF therapy are to correct the underlying cause, reduce associated morbidity and mortality, improve functional status and improve quality of life.
Fluid Management:
Fluid management: Fluid intake is restricted in acute HF where there is lung congestion, peripheral edema despite diuretics, or when there is hyponatremia.
Rest and restriction of activity: Nasogastric feeding is helpful for infants in acute severe HF. Mild-to-moderate aerobic activity should be encouraged in older children with chronic compensated HF.
Correction of anemia: Blood transfusion is generally reserved for severe anemia (Hb 7 g/dL or less).
Nutrition: In infants calorie intake of 120–150 kcal/kg/day is recommended with a fluid intake of 100 mL/kg/day. This is achieved by thickening of feeds or by adding fat (coconut oil/medium chain triglyceride). In older children increase the protein content of the diet while optimizing the fat and carbohydrate intake. Dietary supplementation of calcium and vitamin D3 should be encouraged. Dietary restriction of sodium is generally not recommended in children unless there is severe edema unresponsive to diuretic therapy. Supplementary oxygen may be necessary when there is respiratory distress.
Drug Therapy Goals:
Reduce congestion in lungs and other organs
Increase cardiac output with improved end-organ perfusion:
• Decrease systemic vascular resistance without decreasing tissue perfusion whenever physiologically appropriate.
• Reduction in systemic vascular resistance is not safe when there is dynamic or fixed left ventricular outflow obstruction.
Optimize the preload without causing intra-arterial volume depletion.
Potentially delay disease progression through improved ventricular remodeling.
Diuretics:
It is the mainstay of therapy and reduces systemic and pulmonary venous congestion. Furosemide—usual dose is 1–2 mg/kg q 6–12 hours. In acute heart failure, it can be used as an infusion at a dose of 1–3 mg/kg/day. In case of refractoriness addition of thiazide diuretics such as metolazone may be done. Spironolactone (Aldosterone antagonist) 0.5–1.5 mg/kg q 12 hours decreases potassium loss and may prevent myocardial fibrosis.
It is essential to monitor for hypovolemia, hypotension, hypokalemia, hyponatremia metabolic alkalosis, and renal failure.
Vasodilators:
These are administered in HF only when the altered physiology is likely to benefit from a reduction in vascular resistance such as in systolic ventricular dysfunction with no outflow tract obstruction and acute left-sided valve regurgitation.
Angiotensin-converting enzyme inhibitor: Enalapril—most widely used— 0.1–0.5 mg/kg/day in 2–3 divided doses. Side effects include cough, hypotension, and renal failure. The first dose of 0.1 mg serves as a 'test dose' and helps avoid serious hypotension.
Angiotensin receptor blocker: Losartan 0.75–1.4 mg/kg/day for those patients who do not tolerate Enalapril.
Nitroglycerine/nitroprusside: Acute setting for afterload reduction. This has largely been replaced by milrinone and levosimendan which are essentially vasodilators with an additional inotropic effect (inodilator).
Management:
Inotropes:
Digoxin is an orally administered cardiac glycoside—10 µg/kg/day orally, serum levels to be maintained between 0.5 and 0.9 nmol/L. Intravenous Dobutamine, Dopamine, and Epinephrine are common choices of inotropes, while Milrinone and Levosimendan are used as inodilators.
Beta Blockers:
Reduces tachycardia and improves diastolic filling of the part. It is useful in mitral stenosis, hypertrophic obstructive cardiomyopathy, and tachyarrhythmia-related heart failure. Commonly used agents are non-selective beta-blockers such as propranolol or selective agents such as metoprolol, atenolol, or bisoprolol. Carvedilol (0.1–0.8 mg/kg/day in three divided doses) has additional vasodilatory properties and is most commonly used for the elected case of cardiomyopathy and fersistent ventricular dysfunction after cardiac surgery (such as after ALCAPA repair).
Newer Drugs:
Ivabradine—used to control heart rate with no negative inotropic effect. A combination of Neprilysin inhibitor (Sacubitril) and Valsartan is now increasingly used in children and results of clinical trials are awaited.
A suggested management algorithm for acute heart failure is shown in Flowchart 1.
Source: Indian Academy of Pediatrics Guidelines
Treatment of Advanced Pediatric Heart Failure and End-stage Heart Disease:
Advanced therapies for chronic heart failure include cardiac resynchronization therapy (CRT), ventricular assist devices (typically as a bridge to cardiac transplantation), and heart transplants. These therapies are expensive and there are significant logistic challenges in the Indian setting.
Reference:
Hinton RB, Ware SM. Heart failure in pediatric patients with congenital heart disease. Circ Res. 2017;120:978-94.
Shaddy RE, George AT, Jacklin T, Lochlainn EN, Thakur L, Agrawal R, Solar-Yohay S, Chen F, Rossano JW, Severin T, Burch M. Systematic literature review on the incidence and prevalence of heart failure in children and adolescents. Pediatr Cardiol. 2018;39:415-36.
Venkatesh S, Kumar RK, Heart Failure in Children. IAP Specialty Series on Pediatric Cardiology, 3rd edition. Jaypee Brothers Medical Publishers, New Delhi; 2022. . pp. 351-76.
The guidelines can be accessed on the official site of IAP:https://iapindia.org/standard-treatment-guidelines/