Improvements in 25 Years of Implantable Cardioverter Defibrillator Therapy

Abstract

In 1980, Dr. Michel Mirowski and his team inserted the first implantable cardioverter defibrillator (ICD) in a patient. Initially, ICD therapy was not widely accepted, and many physicians actually considered this therapy unethical. Large secondary and primary prevention trials, demonstrating a beneficial effect of ICD therapy in selected patients not only on arrhythmic death but also on all-cause mortality, stimulated a rapid growth in the number of implants and increased patient's and physician's acceptance. Improvements in size and weight, arrhythmia discrimination capabilities, battery technology, shock waveform and output, monitoring capabilities and defibrillator electrode technology eventually resulted in the current large number of yearly implants. Today, almost 40 years after the conception of the ICD and 25 years after the first human implant, ICD therapy is the treatment of choice for patients at risk for life-threatening arrhythmias either as secondary or primary prevention. Furthermore, with the more recent addition of resynchronisation therapy to standard ICD therapy, it became possible to treat selected patients with advanced symptoms of heart failure and to lower the risk of sudden death.

Fig. 1

Example of abdominal implanted ICD system in a 15-year-old female. ICD implantable cardioverter defibrillator

Fig. 2

Example of pectoral implanted CRT-D system in a 42-year-old male. CRT-D cardiac resynchronisation therapy—defibrillator

Fig. 3

Exploded view of an ICD. ICD implantable cardioverter defibrillator. Image provided by Biotronik

Fig. 4

Cross section of coaxial lead construction of a single coil defibrillation lead with true bipolar sensing and pacing (left) and cross section of multilumen lead construction (right). Image provided by Medtronic