(i) Angina. -When the heart is called upon to work harder, as it is during
exercise or excitement, its need for energy (and oxygen) is increased. Normally
this increased need is met by increased blood flow through the coronary arteries.
If one of the coronary arteries is furred up by atheroma, part of the heart may
not be able to get enough extra blood. Its bank balance then goes temporarily
into debt, i.e., it becomes ischaemic (means not enough blood supply). A
warning pain develops. This pain, called angina, is generally felt as a tightness
of the chest, sometimes spreading into the shoulder, arm or neck. Reduce the
extra work-load by resting and it recovers.
Tablets can help considerably, but not so effectively as stretching the
narrowing (angioplasty) or as an operation to bypass the narrowed segment of
coronary artery; both represent major advances.
(ii) Heart Attack. -When we speak of a heart attack we mean a sudden
blocking of the coronary arteries by a clot (coronary thrombosis). Obviously the
heart muscle supplied by the blocked artery cannot then get enough blood. This
causes pain like that of angina, but in the case of a heart attack, it does not
recover after a few minutes rest. Part of the heart muscle dies (myocardial
infarction). An important new treatment for coronary thrombosis is
thrombolysis- the administration of a drug which dissolves clots and limits
the amount of muscle damage.n The heart attack may be complicated by serious and even fatal
responsible for a large proportion of the deaths that occur in heart attacks,
Most of these occur soon after the onset of the attack. The most important
rhythm disturbance is ventricular fibrillation which prevents any effective
heart-beat at all so that the circulation stops (cardiac arrest). Resuscitation
helps to postpone death for a matter of minutes, but the real need is to
can save lives if applied at once. Cardiac massage with artificial respiration
fibrillation we carry out defibrillation with a specially applied electric
correct the underlying disturbance of heart rhythm. To correct ventricular
shock. It is, therefore, of the utmost urgency to get to a coronary care unit
or a special ambulance where suck facilities are immediately available.
Many more lay people are now being taught emergency treatment to support
the circulation until specialist’s help arrives. Find out where you can learn
this (Cardiopulmonary resuscitation or external cardiac massage).
The damaged area of heart muscle dies and is repaired by scar tissue.
Fortunately the heart possesses considerable reserve capacity, and after
recovery from a heart attack the loss of a small portion need not interfere
with the ability to return to normal activities.
(iii) Sudden death. -Some people die suddenly from the fatal disorder
of heart rhythm without any recognised warning pain. Another cause of
sudden unheralded death is rupture of the heart or of a major blood vessel,
such as the aorta (aortic dissection).