Mikhail Kalashnikov, inventor of the AK-47 assault rifle, has been admitted to the intensive care unit, reports RIA Novosti.  The 94-year-old who has had a series of health ailments recently is best known for creating what is arguably the world’s most popular and well-known firearm.  According to Kalashnikov’s son Viktor, the inventor’s health has been worsening since his birthday earlier this month.  However, he is expected to recover from this most recent episode and his son insists that these procedures are more preventative.

Currently, Kalashnikov is being treated at a state cardiology center in Izhevsk, a city in Siberia.  Officials have not stated what his specific ailment is, but, in June of this year, Kalashnikov was admitted to the hospital to be fitted with a pacemaker.  According to the National Heart, Lung, and Blood Institute, a pacemaker is a small device that’s placed in the chest or abdomen to help control abnormal heart rhythms. This device uses electrical pulses to prompt the heart to beat at a normal rate.

Pacemakers are used to treat arrhythmias.  Arrhythmias are problems with the rate or rhythm of the heartbeat.  During an arrhythmia, the heart can beat too fast, too slow, or with an irregular rhythm.  A heartbeat that’s too fast is called tachycardia. A heartbeat that’s too slow is called bradycardia.  During an arrhythmia, the heart may not be able to pump enough blood to the body.  This can cause symptoms such as fatigue (tiredness), shortness of breath, or fainting.  Severe arrhythmias can damage the body’s vital organs and may even cause loss of consciousness or death.

Kalashnikov may have had a complication related to his pacemaker, his underlying cardiac condition, or other health ailments that have cardiac implications.  The American Heart Association journal Circulation published a study on complications related to pacemaker implants.  Researchers note that identifying the source of a complication can be difficult since there are a number of variables related to patient demographic and health characteristics.

The number of patients in North America and Europe who receive a new pacemaker or implantable cardioverter-defibrillator (ICD) yearly is rising.  The need for a pacemaker increases as patients get older, and ICD implantation has also expanded based on recent literature. In the years after initial implantation, device replacement may become necessary for battery depletion or for upgrades to more complex multilead pacemakers or ICDs.  There is a higher rate of complication, particularly with the more advanced systems that have lead additions.