Hemodynamic and respiratory stability in obese vs. non-obese patients during de novo pulmonary vein isolation under conscious sedation

Background:  

Pulmonary vein isolation (PVI) was shown to be safe and effective in obese patients. However, the periprocedural management during catheter ablation (CA) of atrial fibrillation (AF) in obese patients under conscious sedation (CS) might be more complex due to hemodynamic and respiratory compromise.  

Aims:   

To assess hemodynamic and respiratory parameters of de novo PVI in obese vs. non-obese patients at a tertiary center. 

Methods:  

All patients who underwent de novo PVI with either radiofrequency (RF) energy or single shot devices (cryoballoon ablation or pulsed-field ablation (PFA)) between 01/2022 and 01/2024 were prospectively included. All procedures were performed under CS with propofol as well as fentanyl and midazolam if needed. Two groups of patients were compared: obese patients (body mass index [BMI] ≥ 30 kg/m²) and non-obese patients (BMI < 30 kg/m²).  Peripheral oxygen saturation (SpO2), non-invasive blood pressure (BP) and mean arterial pressure (MAP) were monitored throughout the procedure. Hypoxia was defined as SpO2 below 90% and hypotension was defined by either systolic BP (SBP) below 90 mmHg or MAP below 65 mmHg. Frequency and duration of these events were analyzed and compared between both groups. Linear regression was performed to analyze the association between obesity and hemodynamic compromise and logarithmic regression to analyze occurrence of hypotensive and hypoxic events. 

Results: A total of 381 patients, 120 (32%) obese and 261 (68%) non-obese were included. Obese patients were younger (p<0.001), had higher prevalence of persistent AF (45% vs. 60%, p=0.01) as well as more frequent comorbidities such as hypertension (90% vs. 71.65%, p<0.001) and Diabetes Mellitus (23.33% vs. 11.88%, p=0.004). Procedural duration was longer in obese patients (p=0.012) with longer left atrial dwelling time (p<0.001). Obese patients more commonly underwent RF CA (p<0.001). 

Regarding frequency and duration of hypoxia and hypotension no difference was observed. However, SpO2-levels at 30 minutes and MAP level at 120 minutes were lower in obese patients (p=0.04 and p=0.03 respectively) (Fig. 1). No association was shown between obesity and hemodynamic or respiratory compromise in neither linear nor logarithmic regression. However, age, renal insufficiency, coronary artery disease, COPD and prior stroke/TIA and procedural duration were associated with hemodynamic and respiratory compromise (Fig. 2).  

Conclusion:  

De novo pulmonary vein isolation under conscious sedation showed no difference in hemodynamic and respiratory compromise in obese versus non-obese patients. Other patient as well as procedural characteristics were associated with changes in hemodynamic or respiratory stability. Obesity only is not a factor to exclude patients from performing CA of AF in CS.