In 1 study that evaluated patients with SVT who underwent ablation or received medical therapy, questionnaires such as the 36-Item Short-Form Health Survey revealed improved quality-of-life scores in several categories, including physical role functioning (perceived disability from physical limitations), general health percep- tions (perceived physical and mental health), and emotional role functioning (perceived disability from emotional limi- These improvements, measured at 1 to 5 years of follow-up, were greater in patients who underwent abla- tion than in those treated with medical therapy. Other lit- erature, using domains from the 36-Item Short-Form Health and other quality- of-life questionnaires,544 546 suggests that quality of life is improved after ablation for PSVT. However, these data carry important limitations, par- ticularly a lack of an appropriate control group, small sam- ple sizes, and referral bias. Furthermore, patients affected by PSVT carry different experiences. Therefore, firm con- clusions cannot be drawn about the effect on quality of life provided by medical or ablation therapy, and no recommen- dations are provided. See Online Data Supplement 22 for additional data on quality-of-life considerations. Given the rising costs of health care, there is a growing enthusiasm for incorporating economic appraisals of avail- able therapies and resources into guidelines. The 2014 ACC/AHA Statement on Cost/Value Methodology in Clinical Practice Guidelines and Performance Measures 6 called for development of Level of Value categories to accompany COR and LOE in future guidelines. Although basing recommendations on a cost-effectiveness approach to therapy is an important goal for the current and future healthcare economy, it also poses considerable challenges. 