In the first of these studies,24 43 patients with severely symptomatic paroxysmal AF were randomized to treatment with either AV ablation and a DDD-R (dual-chamber rate-adaptive pacing) mode-switching pacemaker or standard drug therapy. A comprehensive evaluation of the patient's QoL was made using the Minnesota Living With Heart Failure Questionnaire, the reliability and validity of which are well established.26 This 21-item, self-administered questionnaire comprehensively covers physical, socioeconomic, and psychological impairments. A score based on how each person ranks each item on a common scale is used to quantify the extent of impairment and how it is affected by therapeutic intervention. In addition, the Specific Symptoms Scale was used to measure the patient's perception of the frequency and severity of arrhythmia-related symptoms. Palpitations, effort dyspnea, rest dyspnea, exercise intolerance, easy fatigue at rest, and chest discomfort were all rated on a scale from 0 to 10.