Common Cardiac Conditions

Heart rate is controlled by a complicated electrical system in the heart muscle that prompts it to beat more quickly when you exert yourself and slower when you are at rest. Heart rate and/or rhythm can be affected by a number of conditions. Heart rate simply refers to the speed at which your heart is beating. Heart rhythm refers to the electrical source that is driving the heart rate and whether or not it is regular in nature. Generally speaking arrhythmias can most often be divided into Bradycardia (heart rate too slow) and Tachycardia (heart rate too fast) conditions. The most common arrhythmia condition is atrial fibrillation. People with this condition have an irregular heart rhythm that is often too fast. Symptoms can include fatigue, palpitations (in which you are aware of your heart racing or pounding), dizziness, and breathlessness.

Treatment for arrhythmias will follow testing to ascertain the exact nature of the condition the patient has and its causes. Tachycardia treatments consist mostly of medication to stop the abnormal rhythm or to slow it down when and if it occurs. Bradycardia conditions may necessitate fitting of a pacemaker depending on the nature of the condition.

The three most prevalent causes of recurring or severe chest pain are musculoskeletal, gastrointestinal and cardiac in origin. Due to the potentially serious causes of chest pain, people who are experiencing it should always consult a doctor to assess the most likely cause. A cardiac origin for chest pain is always a possibility, particularly in middle-aged or elderly patients. If chest pain (or arm, throat, neck, or back) pain is brought on by exertion, then there is a reasonable chance that the pain stems from a cardiac issue.

Patients with chest pain symptoms that suggest a cardiac origin (or with an unknown diagnosis) should consult a cardiologist. The cardiologist will obtain a detailed history of the pain, examine the patient and perform an ECG taken. Often further tests such as an exercise treadmill test or an echocardiogram may be conducted to further assess the likelihood of the chest pain being cardiac in origin.

Heart failure is the term used for conditions in which the heart fails to pump efficiently. This condition can be caused by many diseases including coronary artery disease, high blood pressure, viral infections, overuse of alcohol, and diseases that affect the heart valves. When the heart is operating inefficiently, a number of symptoms may present themselves (based on the underlying cause and level of severity of the condition). Typical symptoms are tiredness, breathlessness on exertion when lying flat, and ankle swelling. A common term doctors use is oedema, which describes fluid retention (usually in the lungs or feet) as a result of the heart pumping inefficiently.

Testing to determine the underlying cause of heart failure can include chest X-rays, electrocardiograms (ECG), echocardiograms (cardiac ultrasound), and angiograms. Treatment is likely consist of several medications over time in a programme initiated and monitored by your GP and cardiologist. These include medication that will control the amount of fluid that builds up, medication to slow down and protect your heart, and medication to "thin" your blood. Dieticians are often consulted regarding this condition as your intakes of fluid and salt can contribute to symptoms. Treatment may also include participation in cardiac rehabilitation programmes (run by trained physiotherapists). Follow up duties for this common condition are often shared by your GP and cardiologist.

Hypertension is simply defined as a blood pressure that is above range considered normal. Blood pressure is expressed in two numbers (in millimetres of mercury pressure). When the heart pumps, it produces the higher figure (called systolic blood pressure) and when it is relaxed, the lower pressure (called the diastolic blood pressure). That still exists within the blood vessels is recorded. 120/80 is considered (on average) a normal blood pressure for adults.

A high blood pressure reading is important because it is evidence that the heart is having to work harder in order to overcome existing blood pressure within the blood vessels. This can lead to increase the muscle bulk of the heart and lead to its enlargement and weakness. Changes in the blood vessels (which become thicker and narrowed) can also take place as hypertension increases the progression rate of atherosclerosis (hardening of the arteries).Hypertension is in fact one of the key risk factors for the development of this condition, and when combined with additional other risk factors such as smoking, high cholesterol levels, or diabetes, artery blockages can result - particularly in the coronary (heart) arteries.

Causes of high blood pressure can be difficult to determine, but many people who have high blood pressure have a family history of the condition, so a genetic cause is likely. Lifestyle factors that can lead to the development of hypertension can include being overweight, eating too much salt in your diet, being physically inactive, and drinking alcohol at levels at elevated levels (more than one or two standard drinks a day).A handful of other causes can be detected by specific testing.

The common condition of high blood pressure (it is estimated that as many as 1 in 5 New Zealanders has the condition) typically produces few symptoms of poor health, unless it is very high or has existed in the body for a long time. The most effective way to detect high blood pressure is thus to have routine checks of your blood pressure made by a doctor.

High blood pressure can be reduced by both lifestyle measures and through the use of medication. Maintaining a normal weight range is a very good place to start, and such measures as keeping physically active most days, opting for a varied low-fat diet with restricted amounts of salt, restricting your alcohol intake to one or two standard drinks per day and quitting smoking (which may not lower your blood pressure, but reduces the risk of hardening of your arteries, heart attacks and strokes) are all effective steps.

High blood pressure medication has been in use since the 1960s and has since become sophisticated and effective. Medications produce different reactions in individuals and trying to monitor the effects of any blood pressure medication you are prescribed and reporting these back to your doctor is a good idea. It can occasionally take several weeks for particular types of hypertension medication to take effect, so you should persist with treatment even if your initial results are negligible.

As described above, ischaemic heart disease is a state in which the atherosclerotic (artery-hardening) process has reached a high enough level that blood flow is reduced to the heart muscle. This condition can result in an acute coronary syndrome (heart attack / unstable angina), exertional angina, heart failure, a finding on a screening stress test or, in the worst case scenario, in sudden death.

Angina is discomfort that stems from a build up of noxious agents in the heart muscle when its blood supply is restricted. Angina is a clinical diagnosis, which means it is based on your doctor’s interpretation of the information you provide them with. Typical angina is not necessarily even a pain, but more a (sometimes intense) discomfort felt as a tightness or constricting feeling in the chest (often in the middle) This discomfort may spread to the back, the neck and/or the jaw, and typically the left shoulder or arm / wrist (and sometimes the right arm as well). Often there is accompanying sweating and/or breathlessness. It is brought on with exercise (unless unstable), and often after eating, and will settle with rest. Angina symptoms typically only last a few minutes, and symptoms of over 30 minutes in duration are likely to be a sign of unstable angina. Angina can also occur as a result of emotional upset, and when lying down in bed. A severe case may present symptoms at rest or at night (but these attacks usually only last 5-10 minutes).

Angina can occur suddenly as an acute coronary syndrome (unstable angina); as the result of a stable (fixed) obstruction when the heart needs to work harder with exercise or emotion, or at rest, provided the narrowed arteries are tight enough (chronic stable angina). It can also be brought on by medical conditions such as infection or anaemia (secondary angina); or when the width a blood vessel is variable due to altered muscle tone in its lining (coronary spasm). Blood vessels are more irritable overnight, and thus angina symptoms often present at night in the right conditions.

Heart palpitations are a sensation experienced when a patient’s heartbeat becomes quicker, stronger, slower, or somehow irregular. They suggest a change in the electrical rate and in some cases the electrical 'circuit' of the heart.

Palpitations are often nothing to worry about, but they can also be of moderate importance or signs of a very dangerous situation. Because of this potential for a serious problem to be associated with or result from heart palpitations, anyone that experiences them should consult their GP. Some patients will require further referral to a cardiologist for more detailed investigation and possible treatment of the underlying issue.

Investigations that are ordered may often include blood tests, an echocardiogram (heart scan), a 24 hour Holter monitor, and/or an exercise treadmill test. Some patients require more extensive investigations. Treatments can range from adjustment via various medicines and to ablative therapy - a therapeutic 'burn' on the inside of the heart to “break” an unwanted electrical circuit, or an implanted defibrillator device for those rare patients that are suffering from serious electrical problems.

“Blackouts” and spells of dizziness are common symptoms throughout the general population. A brief loss of consciousness (such as in a simple faint) is known in medical terms as syncope. Although syncope is infrequently caused by serious heart problems, it is a medically significant event and always warrants an evaluation. Presyncope describes the feeling of lightheadedness during which one feels that they might be about to blackout, but do not.

Both syncope and presyncope are most commonly caused by a sudden drop in blood pressure levels. Sometimes this is caused by an obviously traceable factor (for example having a blood test, or the sight of blood) but on other occasions it may seem like a random occurrence. Loss of consciousness is most typically preceded by common symptoms such as, light-headedness, a dimming of vision, nausea, and/or a feeling of warmth. The person experiencing the symptoms may also feel sweaty or clammy and appear very pale. A speedy recovery typically follows, but blood pressure may remain persistently low for the next 15-30 minutes, which can bring associated feelings of “grogginess” and can often lead to people describing a feeling of being “washed out” the next day.

Less commonly but more seriously, syncope and presyncope can result from heart rhythm abnormalities such as pauses in the heartbeat or a racing of the heart. These problems can themselves stem from defects in the heart’s electrical system, or be associated with diseases of the heart muscle or valves. A careful check of the patient’s history - followed by appropriate heart examinations and checking their electrocardiograph - will usually provide the correct diagnosis and therefore suggest a course of treatment.

A normal heart has four valves. These are thin tissue structures that allow blood to flow in a forward direction when open, but will close to prevent blood from flowing backwards. A heart valve may have an abnormality at birth, or can become diseased due to acute rheumatic fever, an infection, or as a consequence of aging. Sometimes heart valves can fail even if they have a relatively normal structure. For instance this may occur when the heart muscle suffers from a disease process which can weaken and stretch the heart chambers (causing heart failure).

A diseased heart valve can thicken and fail to perform its function properly, which causes an obstruction to the normal flow of blood, or might fail to provide a proper seal and thus allow blood to leak back into a heart chamber in a reverse of the normal blood flow. These consequences can have effects on health that range from trivial to serious, depending on the severity of the lesion. It is often perfectly normal to detect a tiny valve leak when examining the heart with Doppler echocardiography. A significant valve abnormality or problem, however, is normally be accompanied by the presence of a heart murmur on clinical examination. Investigations will then be performed via ECG, chest X-ray, and occasionally other tests (including Doppler echocardiography) are recommended if the murmur is thought to be significant. In many children and in some adults, though, a heart murmur does not necessarily equate to the presence of a heart valve lesion. Such murmurs are sometimes referred to as ‘innocent murmurs’, and have no importance, but do require a careful assessment.

Faulty heart valves do not necessarily require specific treatment, and lesions may be simply be monitored for any changes over a certain time period. Drug treatment to reduce strain on the heart and its valves are sometimes required. If there is a chance that bacteria could cause infection of a damaged valve (bacterial endocarditis) (for example during dental treatment), antibiotics may be prescribed. A severely diseased valve, though, will typically necessitate to repair or replacement via surgery, especially if it has been causing adverse symptoms.