Heart failure, also known as congestive heart failure, is a condition manifested by the inability of the heart to pump enough blood to the organs and tissues of the body. When it occurs, heart failure causes pulmonary stasis with fluid accumulation in the lungs (pulmonary edema) and dyspnea. Certain cardiovascular pathologies with chronic evolution, such as arterial hypertension and coronary heart disease, can lead over time to the stiffening of the heart muscle or the weakening of the muscle fibers that make up its constitution, with the main consequence being the reduction of the pump function.
Heart failure can cause systolic dysfunction (deficiency of heart contraction) or diastolic dysfunction (deficiency of cardiac relaxation), the 2 phases of cardiac activity that follow each other continuously throughout life. During systole, the heart contracts and generates pressure inside the cavities, thus pumping blood to the arteries, and during diastole, the myocardium relaxes, taking oxygenated blood from the lungs. With each contraction, the heart ejects a certain volume of blood into the arteries, ensuring the optimum oxygen and nutrients required for the entire body.
Risk factors and causes of heart failure
Analyzes heart failure | Investigations for the diagnosis of IC
How to establish the diagnosis
Heart failure can be classified as follows: left HF (causes accumulation of fluid in the lungs with the appearance of dyspnea), right HF (causes accumulation of fluid in the abdomen and peripheral edema in the lower limbs), systolic HF (the left ventricle does not contract properly) and HF with preserved ejection fraction (the left ventricle does not relax properly in diastole).
Heart failure is a pathology that can be prevented by proper treatment of coronary disease, hypertension and diabetes, but also by giving up alcohol and tobacco consumption and maintaining a body weight suitable for height.
Heart failure symptoms
Heart failure can have a chronic evolution or it can start suddenly, frequently causing the following symptoms and manifestations:
- Dyspnea from exertion or at rest
- General weakness and severe fatigue
- Peripheral edema in the lower limbs
- Heart rhythm disturbances
- Persistent cough accompanied or not by wheezing (whistling breath) through which aerated pulmonary secretions are eliminated, with blood streaks
- Fluid accumulation in the abdominal cavity
- Lack of appetite
- Difficulty concentrating
- Precordial pain if acute heart failure is caused by an acute coronary event (myocardial infarction)
Risk factors and causes of heart failure
The main causes of systolic heart failure are:
- Smoking
- Arterial hypertension
- Diabetes mellitus
- Myocardial infections
- Primary cardiomyopathies of genetic cause
- HIV infection
- Thyroid disorders
As a result of the action of these factors, pump insufficiency occurs, which causes a decrease in the volume of blood ejected/beat and a reduction in the perfusion of the organs with oxygenated blood. Secondary, pulmonary stasis occurs due to reduced blood uptake by the heart, followed by pulmonary and later systemic congestion.
Diastolic dysfunction in patients with heart failure is rarely encountered in medical practice and is due to insufficient filling of the heart cavities with blood, occurring in the context of a reduced capacity for cardiac expansion caused by infiltrative diseases, untreated hypertension which over time leads to stiffening of the heart muscle or diseases of the pericardium (the sheet that covers the heart) that exert cardiac constriction, preventing proper cardiac filling in diastole.
The risk factors involved in the occurrence of heart failure are represented by:
- Chronotropic dysfunction and desynchronization: dysfunction of the heart’s electrical system manifested by tachycardia or bradycardia along with inefficient electrical conduction at the cardiac level, determines over time the decrease in cardiac performance with the progressive installation of specific pump failure.
- Valvular dysfunction: the improper opening and closing of the valves secondary to acute articular rheumatism, endocarditis or congenital anomalies determines over time the appearance of congestive heart failure.
- Acute heart failure can be caused by severe allergic reactions, the formation of thrombi at the pulmonary level, sepsis, viral infections with cardiac tropism and the administration of certain medicinal substances.
Analyzes heart failure | Investigations for the diagnosis of IC
Paraclinical investigations that can be used to diagnose heart failure are represented by:
Laboratory investigations for the determination of atrial natriuretic peptide ANP and brain natriuretic peptide BNP-useful serum markers in the assessment of heart failure due to their natriuretic and diuretic properties that influence the hydro-electrolytic balance of the body
Pro BNP (B-type natriuretic peptide BNP) and NT pro-BNP – serum markers with prognostic value in left ventricular heart failure due to their good correlation in clinical studies with the severity of left ventricular dysfunction. These markers can be used according to the cardiologist’s recommendations to monitor the therapeutic response of the patient with heart failure and to evaluate the degree of vascular remodeling.
How to establish the diagnosis
The diagnosis of heart failure is established by the specialist doctor based on the information obtained from the anamnesis, the clinical examination of the patient and the paraclinical investigations which can be represented by: electrocardiogram, echocardiography, exercise echocardiography, HOLTER monitoring, myocardial perfusion scintigraphy, cardiac computer tomography, cardiac magnetic resonance, coronary angiography or cardiac catheterization.
After performing the investigations, the doctor can classify the heart failure in one of the 4 stages as follows:
- Grade I Heart Failure with asymptomatic evolution
- Grade II heart failure with limitation of the patient’s exercise capacity due to dyspnea and severe fatigue
- Grade III Heart Failure daily activities are performed with difficulty;
- Grade IV heart failure, the most severe type of heart failure, causes shortness of breath at rest
Treatment of heart failure
The treatment of heart failure includes as the first measure the modification of the lifestyle which involves:
- Adapting the diet to prevent weight gain or normalize it
- Quitting smoking
- Limiting excessive alcohol consumption
- Limiting salt consumption
- It is recommended to avoid physical exertion
- Administration of certain drugs (non-steroidal anti-inflammatory drugs) contraindicated in certain forms of heart failure
- Limiting fluid intake to less than 2 l per day is recommended in selected cases of advanced heart failure
The drug treatment of patients with heart failure has the main purpose of lowering blood pressure, obtaining vasodilatation and eliminating salt and water by increasing diuresis with the help of antihypertensives, vasodilators, angiotensin-converting enzyme inhibitors and diuretics. In certain situations where heart failure is accompanied by heart rhythm disorders, antiarrhythmics and beta blockers can be administered, while severe HF requires mandatory hospitalization for careful monitoring and administration of intravenous treatment.
Interventional and surgical treatment options for patients with heart failure are aimed at correcting the cause that determines the appearance of specific symptoms and include:
- Implantation of a pacemaker, electrical resynchronization and the use of a defibrillator to correct the heart’s electrical dysfunction
- Installation of stents, creation of by-pass to restore coronary blood flow in the case of ischemic heart disease that causes HF
- Replacement or reconstruction of affected heart valves in case of valvular dysfunction.
- Severe cases that do not respond to the previously mentioned interventional and/or surgical treatment methods can currently benefit from a heart and/or lung transplant if the patient is eligible for this type of major intervention
References:
- Clinical epidemiology of heart failure, Arend Mosterd, Arno W. Hoes, BMJ Journals | Heart
- Epidemiology of heart failure, Amy Groenewegen, Frans H. Rutten, Arend Mosterd, Arno W. Hoes
- The Management of Chronic Heart Failure, Jay N. Cohn, The New England Journal of Medicine
- The pathophysiology of heart failure, Clinton D. Kemp, John V. Conte
