Heart failure is a syndrome which is characterized by signs (ie by objective findings that the doctor identifies) and symptoms (ie what the patient feels). It can be the final result of a multitude of conditions and has been described as a silent epidemic. It is currently estimated to affect more than 10% of people over the age of 70.
The signs and symptoms of heart failure are due to a reduced functional or anatomical response of the myocardium, heart valves or pericardium resulting in decreased cardiac output or increased filling pressures within the compartments of the heart at rest or fatigue. Pathophysiology of this syndrome involves neuro-hormonal activation (increased sympathetic system activity, renin-angiotensin system activation) as well as oxidative stress and inflammation.
That is, it is a condition characterized by inability of the heart to perform its key role effectively, ie to receive blood from the venous vascular network, forward it to the lungs (which enrich it in oxygen) and then to receive it again to forward it to the arterial network.
Heart Failure Classification
Current classification of heart failure is based on the left ventricular ejection fraction (LV-EF), a quantity expressed as a percentage (%). Thus we distinguish 3 heart failure classeswith: a) reduced (<40%– HFrEF), b) mid-range (40-50% – HFmrEF) and c) preserved -normal- ejection fraction (≥50% – HFpEF). Left ventricular ejection fraction in clinical practice is estimated by echocardiography. For Heart Failure diagnosis, beyond LVEF, the coexistence of laboratory findings from blood tests (serum natriuretic peptides – BNP or nt-pro-BNP) and other findings from echocardiography (diastolic dysfunction or hypertrophy of the heart walls or dilatation of the left atrium) are required.
Hear Failure Causes
As already mentioned the list is large and not every entity causes heart failure with the same frequency. Among frequent causes are (unregulated or undiagnosed) arterial hypertension, coronary artery disease and valvulopathies. However heart failure can develop as a consequence of toxic agents (eg alcohol abuse, anorexic drugs, chemotherapy, exposure to heavy metals or radiation, etc.), infectious agents (eg after viral myocarditis), autoimmune disease (eg systemic lupus erythematosus, rheumatoid arthritis), genetic disease (eg hypertrophic cardiomyopathy, dilated cardiomyopathy, restrictive cardiomyopathy, laminopathies, dystrophies) infiltrative disease (eg amyloidosis, hemochromatosis, sarcoidosis), metabolic diseases(eg diabetes mellitus, thyroid disease, Cushing’s disease, pheochromocytoma), in renal failure, in the context of tachymyocardiopathy, in the context peripartum cardiomyopathyetc.
Heart Failure Symptoms
A patient with Heart Failure may present with a wide variety of symptoms which may have a different severity from times to times. Sometimes, due to the progressive symptoms onset, the patient may gradually limit his/her physical activity. This may be of so significant degree that the patient may mistakenly believe that he/she is asymptomatic. In this case the patient is deprived from timely management and the first manifestation of the disease may be adverse or even take the form of sudden death.
Typical symptoms include: shortness of breath during exercise (“air is not enough”), episodes of shortness of breath during the night that wake-up the patient, easy fatigue or delayed recovery of strength after exercise, the need to use multiple pillows during sleep in supine position, or leg swelling.
Atypical symptoms include: night cough, weight loss, anorexia, cachexia, palpitations – tachycardia, depression, syncope, fullness, confusion, bendopnea.
Heart Failure Treatment
A key role in the treatment of chronic heart failure has the administration of neurohormonal blockers, ie drugs from the following categories: angiotensin converting enzyme inhibitors (ACEis), β-blockers (b-blockers), mineralcortcoid inhibitors (MRAs), and Neprilysine receptor blockers (ARNI). Further, based on clinical presentation, diuretics (such as furosemide) and/or ivabradine may be administered (to control tachycardia; if in sinus rhythm only). Also, in the quiver of cardiologists there are special devices that aim either to save the patient from fatal heart arrhythmias (defibrillators – ICD) or improve heart function (cardiac resynchronization devices – CRT). The final step in selected patients is the use of mechanical devices to assist cardiac function or even a heart transplant.
It is important to know that the upscaling of the available pharmaceutical and non-pharmaceutical agents is at the discretion of the attending physician based on the respective clinical picture. Especially with regards to implantation of cardiac devices, the criteria are set by the international medical community and do not apply to the entire cohort of patients, but only to those who have specific characteristics.
Ideally, the effectiveness of each treatment intervention (change of dosage, addition of a new drug class) requires a sufficient amount of time to be evaluated (one to two weeks). Hence, systematic monitoring and communication of the patient with the attending physician is required. In addition, the patient should comply with hygienic and dietary advice (systematic monitoring of body weight, avoidance of salt intake, etc.) in addition to medication. That is, the patient himself and / or the people who support him or who care for him / her are an important link in the treatment chain.
Inevitably, in the natural course of chronic heart failure there will be flares and episodes of acute heart failurewhich may require urgent intravenous medication and / or hospitalization (for pulmonary edema). The purpose of close monitoring of the patient is to reduce these episodes as much as possiblebecause they aggravate the overall condition of the patient and are often complicated by problems from other systems (eg kidneys).