Heart failure may develop for any number of reasons, for example, following a heart attack, in the presence of severe and uncorrected valve disease, or as a result of high blood pressure, diabetes or heart muscle disease. Increased stiffness of the heart muscle is an increasingly recognised cause of heart failure, especially in older women, and is called “heart failure with preserved ejection fraction”, since, although the heart can pump well, it cannot relax and fill effectively.

When the heart muscle is not pumping effectively, pressure can build up within the lungs and the chambers of the heart, creating the sensation of breathlessness. If the muscle impairment is mild, breathlessness is only felt with significant exercise, but increasing muscle damage causes breathlessness with even mild activity and is perhaps more noticeable when lying down in bed, such that a patient may start to sleep with more pillows than before. As the symptom progresses, fluid retention and swelling may become noticeable in the form of swollen ankles or distention of the abdomen. The development of atrial fibrillation (an irregular heart rhythm) as a consequence of the strain on the heart may well precipitate symptoms and be the first marker of an underlying problem.

There are many effective drugs to treat heart failure, not only improving or resolving symptoms but also improving outlook and prognosis. In some patients there is a role for an implantable cardioverter-defibrillator (ICD), to reduce the risk of sudden death from a life-threatening change in heart rhythm.

Others may benefit from a particular type of pacemaker called a biventricular pacemaker; this is also known as resynchronisation therapy, since it improves the pumping action of the heart by altering the pattern of electrical activation of the two main pumping chambers, the ventricles. It does this using a combination of three pacing leads, one stimulating the upper chamber, the right atrium, and the other two stimulating the two lower pumping chambers, the right and left ventricles.

Depending on the precise cause of the heart failure, some patients may benefit from surgery, such as coronary artery bypass surgery, or valve repair or replacement; minimal access techniques are also possible, including the percutaneous approaches to aortic valve replacement and mitral valve repair in selected cases.