Acquired Long QT Syndrome: Risk Assessment, Prudent Prescribing and Monitoring, and Patient Education

PURPOSE: To inform nurse practitioners (NPs) about risk factors that precipitate the potentially fatal cardiac arrhythmia torsade de pointe (TdP) in patients with long QT syndrome (LQTS), and to recommend preventative strategies and prudent prescribing advice to use in clinical practice. DATA SOURCES: A review of the current literature is used to explain factors that cause prolonged repolarization during phase 2 and phase 3 of the cardiac action potential and relate these to the development of LQTS and TdP. The major risk factors reviewed are drugs, drug-drug interactions, electrolyte disturbances, and populations at risk for LQTS. CONCLUSIONS: The LQTS is an increasingly recognized cardiovascular problem. Nurse practitioners should be cognizant of the risk factors and be able to apply them in clinical practice. IMPLICATIONS FOR PRACTICE: Recognition of patients at risk for acquired LQTS is imperative in primary care practice. Currently, there are no practice guidelines that address acquired LQTS. In lieu of practice guidelines, the prudent NP uses physiology to guide treatment decisions, especially those decisions related to the use of drugs.