The term “heart failure” can be misleading, as it doesn’t mean the heart has completely stopped working. Instead, heart failure, often referred to as HF, indicates that the heart isn’t pumping blood as effectively as it should. While sometimes used interchangeably with congestive heart failure, which implies fluid buildup and requires prompt medical attention, both terms describe a condition where the heart’s pumping function is compromised.
Your body relies on the heart’s pumping action to circulate oxygen and nutrient-rich blood to all its cells. In heart failure, the weakened heart struggles to deliver an adequate blood supply, leading to fatigue, shortness of breath, and, for some, persistent coughing. Everyday tasks like walking, climbing stairs, or carrying groceries can become significantly challenging.
Heart failure is a serious, chronic condition, often without a definitive cure. However, with proper management through heart failure medications and a healthy lifestyle, many individuals with heart failure can lead fulfilling and enjoyable lives. The support of understanding family and friends also plays a crucial role in managing this condition.
How a Healthy Heart Works
To understand heart failure, it’s helpful to know how a normal heart functions. The heart is a robust, muscular pump, slightly larger than your fist. Its primary function is to pump the correct amount of blood to all parts of the body – this process is known as circulation.
Watch an animation of blood flow through the heart.
The heart comprises four chambers:
- Two Upper Chambers (Atria): The right atrium and the left atrium.
- Two Lower Chambers (Ventricles): The right ventricle and the left ventricle.
The circulatory process begins in the right atrium, which receives oxygen-depleted blood returning from the body. This blood is then passed to the right ventricle, which pumps it to the lungs. In the lungs, the blood is oxygenated.
Oxygen-rich blood then travels from the lungs to the left atrium, and subsequently to the left ventricle. The left ventricle, being the strongest chamber, pumps this oxygenated blood out to the rest of the body.
Essentially, the heart pumps blood through two circuits: to the lungs for oxygenation and to the body’s tissues to deliver oxygen and nutrients. For efficient circulation, these four chambers must beat in a coordinated manner. A healthy heart possesses more than enough pumping capacity to ensure proper blood circulation throughout the body.
What is Heart Failure? Defining the Condition
Heart failure is a long-term condition characterized by the heart muscle’s inability to pump sufficient blood to meet the body’s needs for oxygen and nutrients. In simpler terms, the heart can’t keep up with its required workload. This doesn’t mean the heart stops beating, but rather that its pumping power is less than optimal.
Watch an animation of heart failure.
Initially, the heart attempts to compensate for this reduced pumping capacity through several mechanisms:
- Enlargement (Cardiomegaly): The heart chambers stretch and dilate in an attempt to contract more forcefully. This helps to maintain cardiac output and meet the body’s demand for blood flow. However, over time, this stretching leads to heart enlargement.
- Increased Muscle Mass (Hypertrophy): The heart muscle cells themselves get bigger, leading to an increase in muscle mass, particularly in the ventricles. This allows the heart to pump more powerfully, at least in the short term.
- Increased Heart Rate (Tachycardia): The heart beats faster to circulate more blood per minute, compensating for the reduced amount of blood pumped with each beat.
The body also activates other compensatory mechanisms to maintain blood flow and pressure:
- Blood Vessel Constriction (Vasoconstriction): Blood vessels narrow to elevate blood pressure, counteracting the heart’s decreased pumping efficiency and ensuring blood reaches vital organs.
- Fluid Retention: The kidneys retain more salt and water instead of eliminating them through urine. This increases blood volume, which helps maintain blood pressure and allows the heart to pump more forcefully. However, this extra fluid volume can eventually overload the heart, worsening heart failure.
These compensatory mechanisms are temporary fixes; they mask the underlying problem of heart failure but don’t resolve it. The condition progresses, and heart failure worsens until these compensatory processes become ineffective.
Ultimately, the heart and body can no longer keep up with the demands, and individuals begin to experience symptoms like fatigue, breathing difficulties, or other warning signs of heart failure. These symptoms usually prompt a visit to a healthcare professional and lead to diagnosis.
The body’s ability to compensate explains why some individuals may not realize they have heart failure until years after the heart’s function begins to decline. This underscores the importance of regular medical checkups with your doctor for early detection and management of potential heart conditions.
Heart failure can affect the left side, right side, or both sides of the heart. However, it most commonly begins in the left ventricle. You can learn more about the different types of heart failure to understand the specific ways this condition can manifest.
