Sudden Cardiac Arrest

Diagnosis

Sudden cardiac arrest happens without warning and requires immediate emergency care. Once the heartbeat is restored and you are stable, healthcare professionals perform tests to find the cause. These tests help check how well the heart pumps blood and identify conditions that may increase the risk of sudden cardiac arrest.

Tests often include:

• Blood tests to check for heart damage, electrolyte levels and hormone changes.

• Electrocardiogram to measure the heart’s electrical activity and detect abnormal rhythms.

• Echocardiogram to show heart structure, blood flow and valve function.

• Ejection fraction measurement to see how well the heart pumps with each beat.

• Chest X-ray to examine the heart’s size, shape and signs of heart failure.

• Nuclear scan to evaluate blood flow to the heart during a stress test.

• Cardiac catheterization to detect blockages in the heart arteries. A blockage may be treated during this procedure with angioplasty or placement of a stent.

Treatment

Treatment for sudden cardiac arrest focuses on restarting the heart and stabilizing the condition. Immediate CPR is crucial. Defibrillation with an automated external defibrillator may be needed to reset the heart rhythm. Once at the hospital, tests identify the cause and guide further treatment.

Medicines may be used to correct irregular heart rhythms and treat underlying conditions. Anti-arrhythmic drugs are commonly given. Other medicines may include beta blockers, ACE inhibitors or calcium channel blockers depending on the cause.

Surgeries and procedures may be needed to improve heart function or prevent another episode. These can include:

• Implantable cardioverter-defibrillator, a device placed under the skin to monitor the heartbeat and deliver a shock if needed.

• Coronary angioplasty to open blocked arteries and place a stent.

• Coronary artery bypass surgery to create a new pathway for blood flow around a blocked artery.

• Radiofrequency catheter ablation to block abnormal heart signals causing irregular rhythms.

• Corrective heart surgery to repair structural heart problems.

Treatment continues with close follow-up care to manage the cause and reduce the risk of future events.