What Are Clinical Factors of Baseline AFib History that Predict Clinical ICD Ouctomes?

A new study published in Pacing and Clinical Electrophysiology sheds light on baseline clinical characteristics of patients with atrial fibrillation (AFib) at the time the time of receipt of an implantable cardioverter defibrillator (ICD).

“Atrial fibrillation is frequently present in patients with heart failure (HF) and an ICD, the researchers wrote in their abstract. “This study [aimed] to identify clinical factors associated with a baseline history of AFib in ICD recipients, and compare subsequent clinical outcomes in those with and without a baseline history of AFib.”

Researchers enrolled 566 first-time ICD patients between 2011 and 2018. They then used logistical regression analysis to look for clinical characteristics linked with baseline history of AFib at the time of implantation, as well as Cox-regression proportional hazard regression models used for multivariate analysis. The purpose of the statistical analysis was to tease out associations between baseline AFib history and subsequent clinical outcomes such as ICD therapies, readmission for HF, and all-cause mortality.

According to the analysis results, there were 201 patients in the study with a baseline history of AFib at time of implant. A multivariate analysis revealed that the clinical factors associated with a baseline history of AFib included hypertension, valvular heart disease, body weight, PR interval, and serum creatinine level. A baseline history of AFib was linked with increased risk for anti-tachycardia pacing (HR=1.84; 95% CI, 1.19 to 2.85; P=0.006), appropriate ICD shocks (HR=1.80, 95% CI, 1.05 to 3.09; P=0.032), and also inappropriate ICD shocks (HR=3.72; 95% CI, 1.7 to 7.77; P=0.0001) following a multivariate adjustment. A baseline history of AFib was not associated with any other adverse outcomes following adjustment.

“Among first‐time ICD recipients, specific clinical characteristics were associated with a baseline history of AFib at the time of ICD implant, the authors concluded. “After adjustment for potential confounders, a baseline history of AFib was associated with a higher risk of all ICD therapies in follow‐up.”