Cardiovascular Considerations for Vyvanse in Patients with Right Bundle Branch Block

Definition and Prevalence of RBBB

RBBB is characterized by QRS duration ≥120 ms in adults, an rSR' pattern in leads V1-V2, and S waves of greater duration than R waves in leads I and V6 1
RBBB is detected in approximately 1-2.5% of the general population and may be an isolated finding or associated with underlying cardiovascular disorders 1, 2

Evaluate for symptoms such as syncope, presyncope, dizziness, fatigue, or exercise intolerance, which may indicate more significant conduction system disease 2
Consider cardiac imaging (echocardiography) to evaluate for right ventricular enlargement or dysfunction, structural heart disease, and left ventricular hypertrophy in patients with RBBB 2
Assess for progression to more advanced conduction abnormalities, as bifascicular block (RBBB plus left anterior or posterior fascicular block) carries higher risk 3
Be particularly cautious if the patient has alternating bundle branch block, which is a Class I indication for permanent pacemaker implantation 3
Regular ECG monitoring is recommended to assess for any changes in conduction patterns or QRS duration while on Vyvanse 2
Watch for symptoms of worsening cardiac conduction, including dizziness, syncope, or palpitations 2

Patients with RBBB plus left anterior or posterior fascicular block (bifascicular block) are at higher risk for progression to complete heart block and should be monitored more closely if prescribed Vyvanse 3
If syncope occurs in a patient with RBBB taking Vyvanse, consider immediate discontinuation and cardiac evaluation, as this may indicate progression to higher-degree AV block 4, 3
For patients with more severe forms of conduction disease (e.g., bifascicular block with syncope), consider non-stimulant medications for ADHD treatment 3
If Vyvanse is deemed necessary despite significant conduction concerns, consultation with a cardiologist is strongly recommended before initiation 2