Temporary Cardiac Pacing

What is temporary cardiac pacing?

Temporary cardiac pacing is an intervention that helps the heartbeat get back to a normal pace if it has been temporarily out of rhythm.

In temporary cardiac pacing, wires are inserted through the chest (during heart surgery), or a large vein in the groin or neck, and are directly connected to the heart. These wires are connected to an external pacing box, which delivers a current to the heart to make it beat normally.

Temporary cardiac pacing can be used for days or weeks. But if there are long-term problems with the rhythm of your heartbeat, then a permanent pacemaker may be needed. This is a small pacing box that gets inserted inside the chest.

How does a normal heartbeat happen?

A heartbeat occurs when a small electrical current is delivered to the heart muscle, causing it to contract.

There are four chambers in the heart: two in the upper part, known as the atria, and two in the lower part, known as the ventricles.

The sinoatrial node (see image) sets out an electrical impulse which travels to the muscles of the atria, causing them to contract.

It also reaches the atrioventricular node, which stimulates it to send out another electrical impulse. This travels to the muscles of the ventricles, causing them to contract.

When the muscles of the heart contract, the heart pumps out blood and you get a heartbeat.

Normally, the adult heart beats in a regular rhythm at a rate of about 60 to 80 beats per minute. Proper contractions at a normal heart rate are essential for delivering oxygen and nutrients to your body’s organs and tissues.

How is temporary cardiac pacing done?

Temporary cardiac pacing is inserted in one of two ways:

  • through a long narrow tube (catheter) with an electrode at the tip that is threaded into a large blood vessel, usually in the groin or neck, until it reaches the inside of the heart; this is done with the help of X-ray screening to see the exact position of the catheter; or
  • during cardiac (heart) surgery, where the exposed ends of insulated pacing wires are attached to the outside surface of the heart and then brought through the front of the chest.

A battery-powered pacing box will be attached by cables to the pacing wires. The pacing box is then set to keep the heart rate at 60-100 beats.

Why is temporary cardiac pacing done?

Temporary cardiac pacing is used to maintain a normal heart rate in people whose own heart rate is not pumping enough blood around the body. This may be in slow heart rhythms, fast rhythms or when the heart fails to beat.

Temporary cardiac pacing may be used:

  • following a heart attack (acute myocardial infarction)
  • following heart surgery
  • awaiting insertion of a permanent pacemaker
  • to make the heartbeat faster to override an undesirable rhythm.

What are the risks of temporary cardiac pacing?

In people where temporary pacing has been inserted by placing a catheter into the heart via a large blood vessel, the complications may include:

  • bleeding at the insertion site
  • infection (more likely if the wire is left in place for several days)
  • bleeding if pacing wire has pierced the blood vessel or the heart wall
  • puncture and collapse of the lung if the wire is misdirected (very rare)
  • hiccoughing if the electrical impulse spreads from the heart to the diaphragm (large muscle between the chest and the abdomen), causing the diaphragm to contract.

Anyone who had temporary pacing inserted during heart surgery is at low risk of:

  • infection
  • hiccoughing
  • bleeding following removal of the pacing wires (rare complication).

Another risk of temporary cardiac pacing can be that the pacemaker may fail to work properly (malfunction). In this situation, the pacemaker battery, connections and cables need to be checked for faults and the settings reassessed.

References

  • Temporary cardiac pacing. Brian Olshansky, MD. www.uptodate.com 2015
  • Systematic Assessment of Basic Pacemaker Function Kimberly Scheibly, RN, MS, CNS AACN. Advanced Critical Care Volume 21, Number 3, pp.322–328. 2010
  • Medtronic. Dual Chamber Temporary External Pacemaker. Technical Manual 2013

Disclaimer

The information on this page is general in nature and cannot reflect individual patient variation. It reflects Australian intensive care practice, which may differ from that in other countries. It is intended as a supplement to the more specific information provided by the doctors and nurses caring for your loved one. ICNSW attests to the accuracy of the information contained here but takes no responsibility for how it may apply to an individual patient. Please refer to the full disclaimer.