Complications after a heart attack: what can happen and how recovery works

A heart attack, also called a myocardial infarction, happens when blood flow to the heart is blocked. The NHS says it can be life-threatening and needs emergency treatment in hospital, and that it is usually caused by a blood clot stopping enough blood getting to the heart. The British Heart Foundation (BHF) explains that most heart attacks are caused by coronary heart disease, in which fatty deposits called atheroma narrow the coronary arteries and a clot can form and block the artery, starving the heart muscle of blood and oxygen.

A complication is a problem that follows from the heart attack or its treatment. NHS inform, the Scottish NHS information service, says sometimes there are complications following a heart attack, and that the most common are arrhythmias and heart failure. This page focuses on those and on what recovery involves.

The sources used here describe complications only in general terms. They do not give detailed lists of rarer problems or figures for how often each occurs, so this page does not either.

NHS inform describes arrhythmias as problems with the heart's natural electrical rhythm. The NHS lists feeling that the heart is racing, going too slowly, skipping a beat or fluttering as symptoms that need advice when they come with chest pain.

The NHS advises calling NHS 111 if you have chest pain and feel that your heart is racing, going too slowly, skipping a beat or fluttering. The BHF notes that heart block caused by a heart attack may need a temporary pacemaker in hospital and, if the rhythm does not recover shortly afterwards, a permanent one.

NHS inform describes heart failure as the heart not pumping blood around the body as well as it should. The BHF says it does not mean the heart has stopped working, but that you may need support to help it work better. It lists medicines used after a heart attack including ACE inhibitors or ARBs such as ramipril or losartan, which are prescribed to treat heart failure and high blood pressure, and beta blockers such as bisoprolol, which help control heart rate and lower blood pressure, reducing the workload of the heart so it can recover.

Breathlessness, ankle swelling and unusual tiredness after a heart attack should be reported to your GP or heart team. The NHS advises calling NHS 111 if you are suddenly more short of breath than usual and 999 for severe difficulty breathing.

The BHF says people usually stay in hospital for about 2 to 5 days. After angioplasty with stents it is likely to be 2 or 3 days, and after bypass surgery at least 1 week. At first you are likely to be admitted to a coronary care unit where you can be closely watched, and you will not be discharged until the doctor is certain you are well enough, which may include assessments such as climbing stairs.

At home the BHF suggests gradually building up how much you do, starting with simple steps such as getting up, washing and dressing, then light household tasks and walking around the house. It says it may help to have someone stay with you for the first few days or weeks. The NHS says that for some people recovery takes several weeks with little impact on their life, while for others it can take months or years, and that you will usually need to rest, including taking time off work.

The NHS says medicines after a heart attack may include antiplatelets to help stop arteries getting blocked, statins to lower cholesterol and other medicines to lower high blood pressure, such as ACE inhibitors and beta-blockers. The BHF adds that antiplatelets like clopidogrel or ticagrelor are commonly prescribed for 1 year and that most people are prescribed lifelong aspirin. It stresses taking prescribed medicines even if you feel well, and not stopping them without talking to your doctor.

Cardiac rehabilitation, the BHF says, gives the best chance of recovery by offering talks and information from experts, exercise sessions, regular assessments and the chance to meet people going through a similar experience. NHS inform says rehabilitation is usually a mix of exercise and education sessions, and the team can also advise on driving, mental wellbeing, relationships, sexual relationships and returning to work.

The BHF says a heart attack can be a frightening experience and it can take time to come to terms with what has happened; it is natural to be worried about recovery, feel scared, frustrated and isolated. The NHS says to talk to your GP if you are feeling anxious or have low mood after a heart attack, as they can help you get support.

The NHS says to call 999 for chest pain that feels tight or like squeezing, chest pain that spreads to the arms, neck or jaw, severe difficulty breathing, pale, blue or grey lips or skin, or if someone has passed out and is not responding normally. It also says not to drive yourself to A&E. A heart attack is different from cardiac arrest, which is when the heart stops suddenly and causes loss of consciousness.

On the NHS, emergency treatment, hospital care, cardiac rehabilitation and long-term medicines are provided free at the point of use in England, with follow-up by your GP and cardiology team. The NHS says rehabilitation may be attended in person or remotely.

Private cardiology offers further tests such as echocardiograms and rhythm monitoring, and a second opinion, but acute heart attack care is delivered through 999 and NHS emergency pathways. Whichever route, ask who is responsible for reviewing your medicines and symptoms in the months after discharge.