The evaluation of new symptoms in a patient with ACHD must be tailored to the patient s anatomy, surgical repair, and physiol- ogy. Before considering pharmacological therapies, e- valuation for residual shunts, baffle stenosis, valvular or conduit dysfunction, and collateral vessels, any of which may be amenable to interventions, is an impor- tant consideration. The literature documenting pharmacological thera- pies for patients with ACHD is limited to small studies with limited duration of drug administration and fol- low-up. Additionally, the endpoints used are often sur- rogate markers that have not been validated for clinical decision-making, and studies are also often underpow- ered. However, studies in patients with ACHD do exist and evaluate conventional pharmacological therapy, es- pecially for HF and for arrhythmia, including beta block- ers, angiotensin-converting enzyme inhibitors, angio- tensin-receptor blockers, and aldosterone antagonists, although results vary.S3.17-2 S3.17-9 Pharmacological therapies in patients with ACHD are often directed to specific conditions (ie, beta block- ers for arrhythmia treatment). However, there are lim- ited data examining the benefits of beta blockers in specific ACHD populations. Results from a small study indicate that beta-blocker therapy may have potential to improve functional class in patients with a systemic right ventricle and a pacemaker.S3.17-2 Angiotensin- converting enzyme inhibitors and angiotensin-recep- tor blockers have also been assessed in small studies in specific ACHD populations in which no significant benefit on ventricular function or exercise capacity has Data from 1 small trial with a short follow-up interval in patients with a systemic right ventricle suggest that eplerenone may be associ- ated with reduced myocardial fibrosis, as assessed by Some pharmacological therapies affecting the pul- monary vasculature (eg, endothelin-receptor antago- nists and phosphodiesterase type-5 [PDE-5] inhibitors) Table 12. 