Advances in cardiac pacing and defibrillation.

There have been many evolutionary milestones in cardiac implantable electronic device (CIED) therapy over the past few decades. These advancements have created new  challenges. Right ventricular pacing was the original (late 1950s) breakthrough, however the risk of pacing induced dyssynchrony has become evident. Biventricular pacing provided a viable way to mitigate dyssynchrony, but only benefits certain patients (primarily left bundle branch block and QRS duration ≥150 ms with depressed left ventricular (LV) function). Areas covered: Recent advances have made His Bundle pacing an option that may provide physiological pacing for a wider patient population. Traditional CIED systems utilize transvenous endocardial leads. Unfortunately, leads have been CIEDs' weakest link. Lead-related vascular occlusion, infection and malfunction have spurred the need for percutaneous lead extraction, and development of subcutaneous ICDs and leadless pacing. These options are important for individuals with limited vascular access and those at risk for blood borne infection. Subcutaneous ICDs have been proposed as optimal for younger patients. This recommendation is controversial. Expert commentary: We review recent advances including His bundle pacing, percutaneous lead extraction, leadless pacing and subcutaneous ICDs as well as their potential use in combination. Additional technological evolution promises to make the future of CIEDs exciting.