Prognostic implication of baseline PR interval in cardiac resynchronization therapy recipients

Area of Science:

• Cardiology
• Electrophysiology
• Medical Devices

Background:

• Prolonged PR interval is common in cardiac resynchronization therapy (CRT) recipients.
• Existing data on the association between prolonged PR interval and long-term outcomes in CRT patients are conflicting.

Purpose of the Study:

• To compare clinical outcomes and response to CRT in patients with normal (<200 ms) versus prolonged (≥200 ms) baseline PR intervals.

Main Methods:

• 283 CRT patients (158 normal PR, 125 prolonged PR) were followed for 3 years.
• Baseline intrinsic PR interval was documented.
• Clinical outcomes and reverse remodeling were assessed.

Main Results:

• Prolonged PR interval predicted composite endpoints in univariate analysis (HR 1.49) and heart failure hospitalization in both univariate (HR 1.6) and multivariate analysis (HR 1.6).
• Patients with prolonged PR intervals showed a lower probability of reverse remodeling (64% vs 77%).
• This effect was more pronounced in patients with non-left bundle branch block morphology (41% vs 68%).

Conclusions:

• A prolonged baseline PR interval independently predicts worse prognosis in CRT patients.
• Prolonged PR interval is associated with a lower likelihood of reverse remodeling, especially in non-left bundle branch block patients.
• These findings highlight the prognostic significance of baseline PR interval in CRT recipients.