Increase in heart rate-dependent left atrial pressure is associated with symptoms in patients with paroxysmal atrial fibrillation.

ABSTRACT

BACKGROUND: It remains unclear why some patients with the same heart rate during an atrial fibrillation (AF) have subjective symptoms, whereas others do not. We assessed the hypothesis that different responses of arterial and left atrial blood pressures to rapid stimulation may be associated with the symptoms of AF. METHODS: A total of 110 patients who underwent catheter ablation for paroxysmal AF were retrospectively studied. Asymptomatic AF was defined as a European Heart Rhythm Association score of Ⅰ for AF-related symptoms. The left atrial pressure (LAP) was measured during sinus rhythm (SR), in 10 pacing per minute (ppm) increments from 100 ppm to the Wenckebach block rate in high right atrial pacing. RESULTS: Asymptomatic AF was observed in 19/110 patients (17%). Patients with symptomatic AF showed higher E/e' ratio and gradual LAP increase that was dependent on the pacing rate. Patients with asymptomatic AF had decreased LAP at 100 ppm compared that at SR, and thereafter, LAP gradually increased depending on the pacing rate. The rate of LAP change compared to that at SR was significantly lower in patients with asymptomatic AF than that in patients with symptomatic AF. The rate of LAP change was independently associated with AF symptoms. CONCLUSION: Patients with asymptomatic AF showed lower E/e' ratio and decreased LAP at 100 ppm to rapid stimulation, followed by a steady increase in LAP afterwards. Factors other than left ventricular diastolic dysfunction may be involved in AF symptoms.