RESET-CRT questions the need of defibrillation in CRT for HF

Pacemaker is not inferior to implantable cardiac defibrillator (ICD) device in terms of survival for heart failure (HF), according to the RESET-CRT study presented at EHRA 2022 — thus raising the question on the need of defibrillation in CRT for these patients.

While unadjusted data appeared to yield a survival edge to cardiac resynchronization therapy with defibrillator [CRT-D], there was no difference in survival between the two devices after adjusting for age and other potential confounders.

“The survival difference in favour of the CRT-D patients that was observed in the unadjusted analysis was primarily due to the younger age of the CRT-D patients,” said the investigators.

The dilemma

“The choice between CRT with pacemaker [CRT-P] and CRT-D is a frequent clinical dilemma,” they pointed out.

ICDs works by delivering energy shock to restore heartbeat and thus helps control life-threatening arrhythmias that can lead to sudden cardiac arrest.

“The underlying rationale [of using CRT-D] is the desired protection from sudden cardiac death,” explained the investigators. “Nonetheless, the risk of sudden cardiac death in HF patients has decreased over time, most probably due to advances in pharmacological and non-pharmacological treatment.”

On the other hand, CRT-D can come with the risk of inappropriate shocks, which may bring emotional stress to patients. “[Moreover,] CRT-D devices have a higher risk of device-related problems such as infections, a shorter device longevity, and cause significantly higher costs for the healthcare system,” they pointed out.

Currently, there is no head-to-head comparison between CRT-P and CRT-D in randomized trial and practice varies widely among doctors.

The European Society of Cardiology guidelines recommend that “an individual decision-making for the choice of the type of CRT device in patients undergoing CRT implantation based on parameters that are considered to be associated with the risk for sudden cardiac death and the competing risk for dying from other causes.”

The trial

The RESET-CRT study used data of patients from a German health claim database who underwent CRT implantations, without indication for defibrillator for secondary prevention of sudden cardiac death (847 on CRT-P and 2,722 on CRT-D). [Eur Heart J 2022;doi.org/10.1093/eurheartj/ehac053]

During a median follow-up of 2.35 years, 714 deaths had occurred. In the unadjusted analysis, the cumulative incidence of all-cause deaths appeared to be higher among patients who received CRT-P than CRT-D (hazard ratio [HR], 1.63; p<0.001).

However, the researchers also noted that patients in the CRT-P group were about 6.7 years older than those in the CRT-D group (mean age, 76.7 vs 69.9 years).

After adjusting for age, there was no difference in survival between the CRT-P and the CRT-D groups (HR, 1.13; p=0.165). The HR was 0.99 (p=0.89) after further adjustment for other potential variables.

“In a large health claims database of CRT implantations performed in a contemporary setting, CRT-P treatment was not associated with inferior survival compared with CRT-D,” the investigators concluded.

“Age differences accounted for the greatest part of the survival difference that was observed in the initial unadjusted analysis,” they added.