Frontiers in Heart Failure

The diagnosis of heart failure in children remains challenging. It precipitates changes in circulatory abnormalities, multiple cellular processes and neuro-hormonal status. Many cases are due to congenital disorders .Clinical picture in children ranges from being asymptomatic to having severe life-threatening symptoms. Ross classification was originally developed to determine the presence and severity of heart failure in infants and younger children. Non-invasive imaging studies are necessary in order to make the diagnosis of heart failure in children. Management ranges from medical, interventional to surgical procedures. Heart transplantation remains an acceptable treatment for children with end-stage heart failure.

Heart failure may occur in structurally normal heart or in congenitally diseased heart. Some congenital heart diseases may predispose to heart failure, in different mechanisms and different pictures, as Fallot tetralogy, single ventricle, muscular dystrophy associated cardiomyopathy and left ventricular non compaction. The etiology of heart failure in those patients may be due to volume overload, pressure overload or valve insufficiency. The medical treatment for such patients includes diuretics, B blockers, ACE inhibitors, digoxin and anticoagulations.

Hypertrophic cardiomyopathy (HCM) is an inherited autosomal dominant genetic disease characterised by asymmetrical increased wall thickness of a non-dilated LV chamber. It has a diverse natural history which is attributed to its heterogeneous clinical presentation. HCM could be diagnosed clinically, by ECG changes and definitely by echocardiographic characteristics. Pharmacological therapy has an important role in the management of HCM. Alcohol septal ablation and pacing may be used in certain conditions. Septal myectomy, Morrow procedure, is indicated to reduce persistent gradient and alleviate symptoms refractory to medications.

Echocardiography remains the cornerstone of the evaluation and management of heart failure despite the availability of other cardiac imaging modalities. It provides adequate and reliable information on diagnosis, therapeutic options and prognosis in every stage of heart failure. It is reliable, reproducible, widely available and cost-effective tool for the evaluation of heart failure. Echo is fundamental in the initiation and adjustment of medication, patient’s selection for device therapy and heart transplantation. Furthermore, it is crucial in the follow up and evaluation of response to advanced therapy. Despite the limitation of echo-derived ejection fraction, it is the single most important factor in the enrollment in clinical trials and therefore, clinical decision making in the daily clinical practice. New advances in echo open promising new frontiers in utility of echo in prevention, detection and management of heart failure.

Non-invasive cardiac imaging plays a pivotal role in the contemporary care of heart failure. It has a tremendous potential for better comprehension of the mechanism of heart failure, detection of subclinical disease, assessment and classification of the current state of the established disease and provision of insights regarding prognosis and response to therapy. Cardiac magnetic resonance (CMR), cardiac computed tomography (CCT) and nuclear cardiology provide robust diagnostic and prognostic information. CMR provides the most comprehensive information but it is limited by the availability. Nuclear cardiology, particularly positron emission tomography (PET), provides high diagnostic yield and has exceptional potential in molecular imaging, but is limited by the ionizing radiation and availability. CCT has an established role in the diagnosis of coronary artery disease and an evolving role in tissue characterization, but like nuclear cardiology, it is limited by associated radiation exposure. This chapter discusses the role of CMR, CCT and nuclear cardiology in the management of heart failure.

The most likely etiology of cardiac failure in neonates, children and young adults varies greatly by age and is often different from the type of etiology seen in adult patients. As such, the need for cardiac catheterization and endomyocardial biopsy depends on the (potential) underlying diagnosis and has to be carefully evaluated for every case, including the need for anesthesia, angiography and cardiac output evaluations.

There are different interventional & surgical modalities for management of resistant or end-stage heart failure. Biventricular pacing and cardiac resynchronization therapy are used in patients with failed medical treatment. Implantable defibrillator could be implanted in patients with recorded syncope, aborted sudden death or malignant ventricular arrythmia. Mechanical circulatory support has been utilized as a bridge either to recovery in cases of reversible etiologies or heart transplantation in cases of irreversible causes.