What is Heart Failure?
Heart failure is a disease characterized by the heart's inability to pump blood adequately. This can occur due to problems in the contraction or relaxation of the heart muscle, compromising the body's functioning. When not treated properly, it can impair the patient's quality of life.
Heart failure can affect any age group and currently affects 1 to 2% of the population. Over the years, the risk increases, and after the age of 55, it can reach 30%.
Symptoms
The disease can develop gradually, and the signs vary from person to person. Here are some of the most common symptoms of heart failure:
- Shortness of breath: can occur during physical activity, when lying down, or even at rest
- Fatigue: feeling of tiredness and lack of energy
- Swelling (edema): can affect the ankles, legs, abdomen, and in more severe cases, the lungs, causing difficulty breathing
- Unexplained weight gain: reaction caused by fluid retention
- Persistent cough: occurs when fluid accumulation in the lungs causes airway irritation
- Irregular heartbeats: cardiac arrhythmias, such as atrial fibrillation, are more common and can cause palpitations and dizziness
- Difficulty concentrating: heart failure can reduce blood flow to the brain, causing mental confusion
Types of Heart Failure
There are three types of heart failure:
- Heart failure with reduced ejection fraction: when the heart loses strength to contract, showing on the echocardiogram (heart exam) an ejection fraction (blood pumping) less than 40%
- Heart failure with preserved ejection fraction: when the relaxation of some heart muscles is not working well, but the blood pumping on the echocardiogram has a value above 50%
- Heart failure with mildly reduced ejection fraction: when the echocardiogram shows that the blood pumping is in the range of 40 to 50%
The percentages indicate the amount of blood the heart pumps with each beat. The ejection fraction is an important indicator to assess the heart's functioning efficiency.
Causes
Heart failure is the common result of heart problems that take into account environmental and genetic factors. Some of the main risk factors are:
- Hypertension
- Diabetes
- Smoking
- High blood fat levels
- Lack of physical exercise
- Heart valve problems (which can be caused by wear or inflammation)
- Conditions present from birth
- Excessive alcohol consumption
- Genetic factors
- Autoimmune diseases
- Inflammations (in women, especially after childbirth)
- Exposure to toxic substances (such as treatments against cancer, weight loss medications, and stimulants)
- Infections (usually of viral origin or caused by parasites, such as Trypanosoma cruzi, responsible for Chagas disease)
These factors can lead to the development of heart failure, either directly through cardiovascular changes or indirectly through infections, autoimmune diseases, and genetic factors.
Diagnosis
The diagnosis of heart failure is made through the analysis of symptoms reported by the patient, such as shortness of breath, leg swelling, and difficulty lying down. After suspicion, the healthcare professional may request tests such as echocardiogram, electrocardiogram, and blood tests to confirm the diagnosis.
One of the most important blood tests is the B-type natriuretic peptide (BNP) or its fraction, pro-BNP, which is a hormone produced in response to heart stress.
Treatment
Due to fluid accumulation in the lungs and body, symptomatic patients receive diuretics, medications that act on the kidney, and guidance to restrict salt and fluid intake, which can reduce symptoms. Additionally, guided physical activity is encouraged as it improves quality of life and exercise tolerance, being an important part of treatment.
Currently, there are medications that can help improve heart function and stabilize the condition. In specific cases, the use of a biventricular pacemaker may be considered to improve the coordination of heart contraction and an implantable cardioverter-defibrillator to reduce the risk of arrhythmias (heartbeat alterations).
Surgical procedures, such as correction of congenital heart diseases, myocardial revascularization, and heart valve replacement, may be necessary in specific situations.
For patients who do not respond to clinical treatment, heart transplantation is an option that improves quality of life. Finally, mechanical circulatory support devices, such as artificial ventricles, can be used temporarily to support the heart while awaiting a transplant.
Prevention
Preventing cardiovascular risk factors is essential to reduce the development of heart failure, including proper treatment of hypertension, diabetes, dyslipidemia, smoking, and sedentary lifestyle.
Other actions can also help in prevention:
- Hygiene and housing (aimed at reducing the incidence of rheumatic disease and Chagas disease)
- Reduction of alcohol intake
- Monitoring of family members of patients with heart failure of indeterminate cause and patients using certain types of chemotherapy
References
COSTA, Keyse Cesar; DO NASCIMENTO MOTA, Fernanda Rochelly; RODRIGUES, Karilane Maria Silvino. Preditores de prognóstico da insuficiência cardíaca através de exames de imagem [Predictors of heart failure prognosis through imaging tests]. Research, Society and Development, v. 11, n. 16, p. e344111637804-e344111637804, 2022.
DOURADO, Mavy Batista; OLIVEIRA, Fernanda Santos; GAMA, Glicia Gleide Gonçalves. Perfis clínico e epidemiológico de idosos com insuficiência cardíaca [Clinical and epidemiological profiles of elderly people with heart failure]. Rev. enferm. UFPE on line, p. 408-415, 2019.
MARCONDES-BRAGA, Fabiana G. et al. Atualização de tópicos emergentes da Diretriz Brasileira de Insuficiência Cardíaca–2021 [Update of emerging topics in the Brazilian Heart Failure Guideline–2021]. Arquivos Brasileiros de Cardiologia, v. 116, p. 1174-1212, 2021.