Congestive Heart Failure (CHF)
Congestive heart failure (CHF) is a condition in which the heart does not pump enough blood out to the rest of the body in order to meet the body’s demand for energy. The lungs may get flooded with extra blood and fluid if the left side of the heart is failing. On the other hand, the liver and veins leading into the heart may become congested and distended if the right side of the heart is the problem. In children with certain types of congenital heart defects (obstructed aortic valve or aorta, hole in the heart, leaky valve, and large PDA) have back-up or excessive blood flow into the lungs. It is common for both sides of the heart to fail at the same time and cause congestion, fluid accumulation in the lungs and other parts of the body such as the liver, veins, legs, etc. The extremities, face, liver and back may become edematous (swollen).
Causes of CHF:
There are several causes of CHF in children and adolescents.
Left to right shunts: Patients with certain types of congenital heart defects (hole in the heart, coronary fistula or abnormal connections, PDA and others) may develop CHF if too much blood goes to the lungs, which the lungs and heart find very difficult to handle.
Obstructed valve or artery: Patients with severe obstruction at the level of the mitral or aortic valve or at the main artery leaving the heart (Coarctation of the Aorta) may develop heart failure. The severe obstruction causes the heart to have to work extra hard, to overcome the obstruction, and may weaken or develop fatigue. The weakened heart muscle is unable to pump forward enough blood to meet with the body’s demands. The heart muscle may also become weakened as the heart walls become too thick. In extreme cases the main pump of the heart (left ventricle) may be underdeveloped (hypoplastic) and unable to pump effectively.
Tachyarrhythmia: Patients with persistently very fast heart rates may develop CHF. In this condition the heart muscle may develop fatigue as it is pumping so fast that the heart contractions become ineffective. This condition may be seen in patients with very fast heart rates (usually over 240 beats per minute) lasting for several hours. Other patients’ heart rates may not be as fast but, if it goes uncorrected for many hours or days, it may produce significant dilation of the heart chambers and eventually heart muscle fatigue. Examples of this condition include atrial flutter, atrial fibrillation, paroxysmal supraventricular tachycardia, junctional tachycardia, and ventricular tachycardia.
Bradyarrhythmia: In patients with complete heart block the heart rate is very slow and the heart becomes enlarged and is unable to meet the body’s demands. Patients may faint or become very lethargic.
Weakened heart muscle: A weak heart may be seen with certain types of cardiomyopathy, myocarditis (inflammation of the heart), systemic disease and Kawasaki disease.
Heart attack: This condition is very rare in children and is usually due to a coronary structural abnormality or coronary fistula. In children it is very rare to see extra narrowing of the coronary arteries as is usually the case in adults. Patients with a heart transplant and chronic rejection may develop a heart attack.
Heart transplant and rejection.
High-output failure: Severe anemia, malnutrition, or a hyperactive thyroid makes the heart pump fast and ineffectively.
Symptoms: The symptoms may be different depending on the patient’s age (infants vs. children vs. adolescents). Kids with CHF may experience failure to thrive. The heart uses up a significant amount of calories as it works harder to do its job.
Infants with CHF have a harder time feeding. They take extra time while feeding and do not eat as well as other babies (and can become very sweaty). These infants may have rapid and difficulty breathing and their face and/or extremities may become swollen. The symptoms may get worse during the following weeks or months.
Older children may experience shortness of breath and difficulty breathing with minimal exercise such as climbing a flight of stairs. Children in failure often lack energy and their appetite may be poor. They also experience changes in their weight and difficulty sleeping. There might be swelling of the extremities or face and the liver may be enlarged due to congestion. Other symptoms include coughing, dizziness, palpitations, fainting, and chest pain.
Tests and Diagnosis of CHF: Past and present history are important in order to determine a cause. A detailed history includes any symptoms and if there is failure to grow. Physical examination may be remarkable for gallop rhythm, diminished heart sounds, heart murmurs, liver enlargement, swollen extremities, fast heart rates, abnormal blood pressures, changes in skin color, poor circulation and crackles in the lungs.
Blood tests, electrocardiogram, echocardiogram, chest x-ray and, in some cases, a 24-hour Holter recorder are included as part of the work-up. Some patients may require exercise testing, cardiac catheterization or MRI.
Treatment of CHF: Most patients will require treatment of CHF with several medications. On the other hand, in other patients, CHF may disappear if they have a treatable cause, such as anemia, hyperactive thyroid or an arrhythmia. Children with certain types of congenital heart defects (like holes in the heart) may require medical treatment as a temporary solution to allow the hole to get smaller and to give the infant a little more time to grow before considering heart surgery.
Kids with complex congenital heart defects may require surgery within the first weeks of life. Some patients (such as those with cardiomyopathies) with severe CHF may be candidates for heart transplantation.
There are several types of medications used to treat CHF. Digoxin is a medication used to make the heart squeeze better and help pump blood more efficiently. It may also be used to treat certain types of arrhythmias. Beta-blockers (Metoprolol, Carvedilol, Propanolol/Inderal) may be used to lower the blood pressure and/or fast heart rates. Other medicines help decrease the workload of the heart and lower the blood pressures, like an ACE-inhibitor (Enalapril/Vasotec, Lisinopril). These medications should not be used in ladies who may become pregnant. Diuretics (water pills) such as Hydrochlorothiazide, Aldactone, Lasix, help the kidneys to eliminate extra fluid in the lungs and the rest of the body. Excessive salt intake may be deleterious as it may result in excessive water retention.
Patients in CHF need extra nutrition and may require oxygen. Patients with CHF have restrictions from certain kinds of exercise.
Outcome: Outcome depends on the cause and whether CHF is reversible or not. For example, if CHF is due to a hyperactive thyroid this can be treated. Most patients with a tachyarrhythmia (very fast heart rate) may have resolution of CHF once they are treated either with anti-arrhythmic medicines or catheter ablation. CHF secondary to a congenital heart defect may have a good outcome once they undergo heart surgery. Babies with more complex heart defects may have variable results. About 2/3 of patients with cardiomyopathy may improve or their condition may remain stable. About 25-40% of patients with certain types of cardiomyopathies may die suddenly or require heart transplantation.