Myocarditis Associated With Herpes Zoster in a 91-Year-Old Woman: A Rare Cardiac Complication With Favorable Outcomes

Herpes zoster-associated myocarditis is an exceedingly rare and underreported complication of varicella-zoster virus reactivation. We describe a 91-year-old woman who developed a typical herpes zoster rash and, six days later, was admitted with clinical, laboratory, and echocardiographic evidence of acute heart failure suggestive of myocarditis. The patient improved rapidly with optimized heart failure therapy and escalation of valacyclovir, was weaned off oxygen and diuretics, and discharged in stable condition. A follow-up echocardiogram demonstrated marked recovery of left ventricular function. This case highlights the importance of recognizing rare cardiac complications of herpes zoster, such as myocarditis, and underscores the need for preventive strategies, including vaccination. Clinicians should maintain a high index of suspicion for myocarditis in patients presenting with new cardiac symptoms following herpes zoster infection.