Medication is very important, and forms the basis of therapy. The most common causes of heart failure are ischaemic heart disease (that is, blocked arteries supplying blood to the heart muscle), hypertension (elevated blood pressure), cardiomyopathy (disease of the heart muscle itself, causing it to be weak and less effective) and valvular disease (some malfunction of the various valve systems between the heart chambers and vessels entering and leaving it). As these conditions gradually worsen, the clinical picture will vary, as will the signs and symptoms the patient experiences and the physician notes.
Drug medication is based essentially on the use of four types of medication:
- Initial treatment with a potent diuretic.
- An angiotensin-converting enzyme (ACE) inhibitor.
- Digitalis with heart failure complicated by a heartbeat irregularity (called atrial fibrillation).
- The nitrates, if necessary, to assist with symptomatic benefit.
Let’s look at some of these more closely.
The diuretics have been among the key advances in recent years. Now there is a large variety. They all have the same basic effect, although each differs marginally, and claims accompany each new discovery. Their net effect is to reduce the fluid content of the body. They arc usually taken by mouth, although some (such as frusemide) may be injected directly into the bloodstream if urgent results are needed. A prompt and satisfactory diuresis (passing of fluid through the urinary system) invariably takes place.
This has the effect of reducing the volume of circulating fluid, as well as lowering the load on the lungs, and lessening the amount of work the heart must perform, thus generally eliminating oedema. Often the beneficial effects are little short of dramatic.
Cardiac patients will be familiar with names such as chlorothiazide (the first oral diuretic of this type to be developed), ethacrynic acid, frusemide, hydrochlorothiazide, bendrofluazide, cyclopenthiazide, spironolactonc and others.
New chemical formulations are still entering the commercial market. Many have specific advantages over their competitors. For example, frusemide tends to act rapidly, and the diuresis it produces is usually all over within a few hours. This may be important in ambulant patients who desire to be out and about. The fear of a constant urgency to pass urine throughout the day may be an embarrassment.
Many of the diuretics tend to deplete the system of the important electrolyte potassium. For this reason, potassium supplements arc often administered orally at the same time. Sometimes toxic effects from the diuretics occur, and include excessive water loss, cramps, weakness, malaise, apathy and vomiting.
These symptoms must be reported should they take place in a patient taking diuretics. Other forms of therapy are still sometimes used. If irregularities of heartbeat occur, the beta-blocking family of tablets may be used. If oxygen lack is a feature, oxygen administration may be necessary.
Once, removal of blood from the veins by venesection sometimes relieved the burden on the heart and gave assistance. But with today’s modern range of drugs, this is seldom necessary. Other methods were used to drain fluid from the tissues, such as the introduction of tubes into the tissues of the lower limbs. Southey’s tubes were used for this purpose, but this is never seen in the modern setting.
Heart failure is a common disorder in the community. It affects vast numbers. Early recognition is the prime necessity, and correction of the possible causes. The early professional attention of the doctor will guarantee the best results. The sooner telltale symptoms are treated, the better the outlook, for the sooner effective therapy may be started.