Cardiodefibrillators

What are defibrillators

Defibrillators are devices that restore a patient's normal heartbeat by sending a small electrical pulse or electric discharge to the heart. The devices are used to prevent or correct cardiac arrhythmia, as well as uneven, too slow, and possibly too fast heartbeat. Defibrillators can also restore the heartbeat if the heart suddenly stops.

Defibrillators restore a patient's normal heartbeat by sending a small electrical pulse or electric discharge to the heart

As explained by Zdrav.Expert Dmitry Kashka, an anesthesiologist-resuscitator of the highest category, a member of the Association of Anesthesiologists-Resuscitators, the Association of Obstetric Anesthesiologists-Resuscitators and the Russian Society of Surgeons, in simple words, defibrillators are devices capable of restoring effective cardiac activity by means of an electric pulse. They are used in the process of cardiopulmonary resuscitation complex, since one of the main causes of cardiac arrest (or it is more correct to say effective cardiac activity) is ventricular fibrillation - chaotic, unsynchronized contractions of myocardial muscle fibers. Defibrillation allows you to synchronize contractions and restore effective cardiac activity.

Defibrilators are professional, which are used by resuscitators and automatic doctors, which are installed in crowded places and are intended for the primary resuscitation complex by non-professionals, Kashka said.

How defibrillators work

Defibrillators of different types work in different ways. Automatic external defibrillators (AEDs) have been developed to save the lives of people experiencing sudden cardiac arrest. Even unprepared passers-by can use these devices in an emergency. Other defibrillators can prevent sudden deaths of people at high risk of life-threatening arrhythmias. These include implantable cardioverter defibrillators (ICDs) that are surgically placed inside the body and wearable cardioverter defibrillators (WCDs) that are mounted on the body.

Automatic External Defibrillators (AEDs)

The AED is a battery-powered portable device that tests heart rate and sends a discharge to the heart to restore normal rhythm. The device is used to help people with sudden cardiac arrest. Sticky pads with sensors, called electrodes, are attached to the breasts of a person who has problems working the heart. Electrodes send information about a person's heart rate to a computer, the device analyzes the heart rate to determine if an electric shock is needed. If necessary, electrodes are discharged.

Automatic external defibrillator

AED defibrillator device

Implantable cardioverter defibrillators (ICDs)

ICD is surgically injected into the chest or abdomen where it checks for arrhythmias. Arrhythmia can disrupt blood flow from the heart to the rest of the body or cause cardiac arrest. The ICD sends a bit to correct the arrhythmia. An ICD can emit a low-energy discharge to accelerate or slow an abnormal heartbeat, or a high-energy discharge that can correct a fast or irregular heartbeat. If the low energy discharges do not restore the normal heart rate, the device will switch to high energy discharges for defibrillation.

Implantable cardioverter defibrillator

The device will also switch to high-energy discharges if the ventricles begin to tremble rather than contract much. ICDs are similar to pacemakers, but they only provide low-energy electric shock. The medical device has a generator connected to the wires to detect heart pulses and supply a discharge if necessary. Some models have wires that lie in one or two heart chambers, while others don't have wires threaded into the heart chambers, but the devices rest on the heart to control heart rhythm.

ICD can also record cardiac electrical activity and heart rhythms. The records can help the doctor fine-tune the devices to better correct an irregular heartbeat. The defibrillator will be programmed to respond to the type of arrhythmia that the patient is most likely to have.

Wearable cardioverter defibrillators (WCDs)

WCDs have sensors that attach to the skin. The sensors are connected by wires to a device that checks the heart rate and delivers an electric shock if necessary. Like ICD, WCD can produce small and high energy discharges. The device has a belt attached to the vest and is worn under the garment. The doctor will select the device to the size of the patient. The device is programmed to detect a specific heart rate.

Wearable cardioverter defibrillator

Sensors detect the occurrence of arrhythmia and notify the user of this. The patient can turn off the alert to prevent discharge if not needed, but if the user does not respond, the device will discharge to correct the rhythm. This usually happens within one minute. The device can apply repeated electrical discharges during an episode, and after each episode the sensors must be replaced. The device can also send doctors records of their patient's cardiac activity.

Who is prescribed a defibrillator

• Life-threatening heart rhythm disturbance or risk of it occurring;
• Genetic disorders affecting the heart, such as cardiomyopathy, Brugada syndrome, or prolonged interval syndrome;
• Heart failure;
• Cardiac arrest;
• Congenital heart disease.

Basic rules for using defibrillators

AEDs can save the life of someone who has a sudden cardiac arrest when the heart suddenly and unexpectedly stops beating. The device can be used for adults, as well as for children over the age of 1 year. Some devices have pads and cables designed specifically for children. ICDs can correct dangerous arrhythmias or prevent an irregular heartbeat that will not lead to sudden cardiac arrest. Life-threatening arrhythmias can develop for many reasons and affect people of all ages, from newborns to the elderly. A doctor may recommend ICD if a patient has a type of arrhythmia in which the ventricles of the heart tremble rather than pump blood, this type of arrhythmia most often causes sudden cardiac arrest. WCDs are used to protect against sudden cardiac arrest in certain circumstances, for example if the patient is at risk of arrhythmia for a short time. This can happen in people under the following conditions: a person recovers from a heart attack, waits for a heart transplant, fights an infection, removes his ICD or waits for a replacement.

Side effects from defibrillator

• Arteriovenous fistula or arteriovenous fistula (abnormal connection between the artery and the vein);
• Blood clots in arteries or veins;
• Lung injury, lung collapse, or bleeding from lung cavities;
• A hole in the blood vessels;
• High defibrillation shock;
• Rejection phenomena;
• Excessive or insufficient heartbeat sensitivity may result in shock or treatment failure, respectively;
• Surgical complications at the incision site, such as bleeding, infection, inflammation, and blood clots.

Defibrillators (global market)

Main article: Defibrillators (global market)

2023

Presented a wearable defibrillator that can not be removed in the shower

On November 13, 2023, Element Science announced the Jewel portable wearable cardioverter defibrillator designed to prevent sudden death due to cardiac arrest. The device has a waterproof design, so that it can not be removed in the shower. Read more here.

It's dangerous for people with pacemakers to wear fitness trackers and smartwatches

On February 21, 2023, it became known that technologies for determining bioimpedance in smartwatches could threaten health when used with implantable medical devices, including pacemakers.

The study, published in the journal Heart Rhythm, claims smartwatches and other fitness trackers can interfere with pacemakers and other implanted devices. Wearable devices, usually focused on monitoring aspects of our health such as heart rate, blood pressure and other vital signs.

People with pacemakers should not wear smartwatches

However, the researchers argue that despite the obvious benefits, some fitness and wellness trackers can pose a serious danger to people with implantable cardiac electronic devices (CIEUs) such as pacemakers, implantable cardioverter defibrillators (ICDs) and cardiac resynchronization therapy (CPT) devices.

According to the researchers, the popularity of wearable medical technologies has been rapidly growing since the beginning of 2014, the line between medical and consumer devices is being erased. Before this study, according to scientists, an objective security assessment did not keep up with the new gadgets.

Scientists found that the electric current used by the bioimpedance sensor of fitness devices interfered with the proper functioning of some implanted cardiac devices. Bioimpedance detection technology sends a small, discreet electric current to measure a person's body composition, including body fat levels, muscle mass, stress levels and respiratory rate. With it, fitness trackers can record various health-related indicators.

Bioimpedance sensing created electrical interference that exceeded the norm and interfered with the proper functioning of CIED, the researchers said. The results obtained, according to the World Health Organization (WHO), do not indicate any immediate or obvious risks: however, a high level of electric current can indeed lead to an interruption of pacing.^[1]

2021: Announcement of a compact defibrillator that does not need to be implanted under the skin

In early August 2021, the American company Kestra Medical Technologies released a compact wearable cardioverter-defibrillator Assure, which does not need to be implanted under the skin. Read more here.

2020: Philips reveals its defective defibrillators

In March 2020, Philips issued a warning about defective HeartStart MRx defibrillator monitors. The manufacturer received a number of reports that some HeartStart MRx devices stopped working after they were dropped or subjected to severe mechanical shock. The change and/or complete loss of performance was noted even when there was no visible external damage to the defibrillator and the Ready to Use indicator continued to burn. Read more here.

2019

Philips recalls defective defibrillators after two patients die

In late October 2019, following the deaths of two patients, Philips recalled defective HeartStart XL + defibrillator monitors that could delay the start of therapy and endanger patients' lives. Read more here.

Mindray unveils BeneHeart C-series smart external defibrillators

On September 12, 2019, the company, a Mindray global developer medical of equipment and destination solutions, introduced an automated external defibrillator, BeneHeart C Series characterized by intelligent algorithm action and accelerated electric impulse to improve the effectiveness of resuscitation measures in case of a sudden stop. hearts The range, introduced in both full and partially automated versions, is available to customers in some To Europe other countries around the world for September 2019. More. here

Medtronic agreed with US authorities to hide data on tens of thousands of complaints about defective defibrillators

At the end of May 2019, Kaiser Health News, a nonprofit news outlet specializing in coverage of problems in the field, health care published a report according to which Medtronic it agreed with the authorities to USA hide data on tens of thousands of complaints about defective defibrillators. More. here

2017: Recommendations for patients with ventricular arrhythmia

The American Heart Association, American Heart Society and Heart Rhythm Society issued updated guidelines in November 2017 advising the implantation of subcutaneous cardiovertefibrillators in patients with ventricular arrhythmia.

Thanks to the latest technologies, clinical data in this area is updated very quickly, says doctor Kenneth Stein. - The revised guidelines took into account new clinical and experimental data that have been obtained over the past ten years.

By mid-November 2017, Boston Scientific's EMBLEM MBL S-ICD system is the only implantable cardiovertefibrillator on the market that protects patients at risk of sudden cardiac death while not affecting normal heart activity.

EMBLEM MBL S-ICD Cardiodefibrillator from Boston Scientific

Experts recommend implanting a cardiovertefibrillator in all patients who are shown to use defibrillators without constant stimulation. In addition, it is strongly recommended to use such a device in people with poor vascular access or with a high risk of infection, including patients with diabetes mellitus.

This is a new treatment technology, and before recommending it to patients who might otherwise continue to receive standard therapy, doctors had to obtain clinical data from long-term studies. Dr Stein sees these recommendations as a call to action - doctors should consider the new treatment when choosing to treat patients with relevant indications.

The new recommendations, combined with the latest data from long-term clinical studies and experience with these systems, suggest that implantable cardiovertefibrillators can and should be considered as first-line therapy in patients with relevant indications, he said.[2]

Notes