Heart Attack – Complications
I. Cardiac dysfunction – Involvement of a large portion of heart muscle can affect the pumping function of heart which may be reflected as sudden breathlessness (Acute left ventricular failure) or a fall in blood pressure (cardiogenic shock). These complications can be managed by drugs but in severe cases mechanical assistance by intraaortic balloon pumping system (Aortic counterpulsation) may be needed.
II. Disturbance in rhythm of heart (Arrhythmia) – Disturbance in rhythmic contraction of heart is one of the most common complications. But, fortunately most of them are not very serious. The deficient blood supply in heart muscle, electrolyte disturbance, autonomic imbalance contribute to development of disturbed rhythm of heart. Rest, pain relief, correction of electrolyte imbalance and reassurance can prevent arrhythmias. Ventricular tachycardia and fibrillation are the serious complications which require immediate measures (drug therapy or DC shock)
III. Recurrent angina – Recurrent or persistent chest discomfort is a common complication of heart attack especially after successful dissolution of clot (thrombolysis). It often denotes extension of the damage and repeat thrombolysis or angioplasty may be required.
IV. Pericarditis – The involvement of outer covering (pericardium) of heart may also cause chest pain but unlike anginal pain, it increases while taking the breath and decreases by sitting and leaning forward. This pain responds to aspirin. Dressler’s syndrome is form of pleuro pericardial chest pain associated with fever occurring few days to 6 weeks after heart attack. This also responds to treatment with aspirin.
V. Clot embolism – Blood clot (thrombus) formed inside the heart or in veins of leg may detach and block the circulation at distant site like in lungs or brain leading to pulmonary infarction and stroke. Anticoagulant therapy (e.g. heparin) decreases the incidence of such episode.
VI. Mechanical complications – Necrosis (death) of the muscles may cause mechanical defects which can lead to disturbance in heart function (Cardiac failure) or fall in blood pressure (Cardiogenic shock). There may be perforation (hole) in the septum (partition) dividing the two chambers of the heart (ventricular septal defect), rupture of the muscle which stabilizes the valve leaflets (Papillary muscle rupture) or even rupture of muscle wall.
VII. Aneurysm of left ventricle – This is a late complication of heart attack in which the necrosed area move paradoxically increasing the work load on remaining viable heart muscles. The chances of clot formation and detachment (embolism) leading to serious consequences as well as abnormal rhythm of heart (arrhythmia) is increased in cases of aneurysmal dilation.