Electrical noise might have caused an inappropriate ICD discharge. We’ve long been writing about the problems with lead wires and implanted defibrillators, but now, a surprising situation is emerging out of Denmark, HealthDay News reports, citing a New England Journal of Medicine report.
“We recently cared for a patient who, after receiving an implantable cardioverter defibrillator, was readmitted shortly after hospital discharge because of two shocks delivered while the patient was showering,” said the March 26 article, reported HealthDay.
There was no clear reason for the device to have activated; however, according to the report, a review “raised suspicion that electrical noise had caused an inappropriate ICD discharge.” The Danish doctors had an electrician analyze the home’s electrical wiring, said HealthDay.
Implanted defibrillators deliver a shock to return an arrhythmic heart
Implanted defibrillators deliver a shock to return an arrhythmic heart back to normal rhythm. In this case, there was no precipitating arrhythmia, or irregular heartbeat, to provoke the device from engaging.
“It was found that it was due to improper installation of wiring in the patient’s home because he installed a washing machine himself,” said Dr. Kristian Eskesen, a cardiologist at Gentofte Hospital in Hellerup and a report co-author, said HealthDay. “It was not properly grounded,” Dr. Eskesen explained.
According to Dr. Eskesen, had a licensed electrician installed the machine, the shock likely would not have occurred, said HealthDay. In Denmark, safe grounding is legally mandated.
The report from Denmark is not the first of its kind, said HealthDay, in Hong Kong in 2002, a cardiologist reported one case prompted by signals from a power drill and another from a washing machine; in Germany, a similar case originated from a washing machine’s signals, reported HealthDay.
“The reason for writing our report was to make colleagues aware of this possible problem,” said report co-author Dr. Soren Hjortshoj, of Aalborg Hospital, in Aalborg, Denmark, adding, “… physicians should be aware of the possibility of false shocks and the reason for these,” quoted HealthDay.
Meanwhile, Medtronic’s Sprint Fidelis defibrillator leads have been implicated in at least 13 deaths and could be linked to scores of others; up from the five fatalities Medtronic reported when the Sprint Fidelis leads were first removed from the market in 2007.
the defibrillator can emit a massive and painful shock
A lead is a wire that connects an implantable defibrillator to the heart. If a lead breaks, the defibrillator can emit a massive and painful shock or worse, a fractured lead can prevent a defibrillator from sending a necessary, lifesaving shock to the heart. Replacing a lead is not an easy procedure and surgery can cause the tissue of the blood vessels and heart to tear.
In a letter sent to doctors, Medtronic said that the faulty wires were a “possible or likely contributing factor” to the 13 deaths. Four of the deaths occurred when doctors tried to remove defective Sprint Fidelis leads from patients.
The company also said in the letter that it has received a total 107 reports claiming that the Sprint Fidelis lead “may have caused or contributed to a patient death.” An independent doctor panel is currently reviewing 89 of those claims, the Medtronic letter said.
According to an earlier Wall Street Journal report, it is estimated that about 150,000 Sprint Fidelis leads remain implanted in U.S. patients.