Lyme carditis associated with Borrelia burgdorferi infection was uncommon but was linked to two previously unsuspected cases of sudden cardiac death, Joseph D. Forrester, MD, from the Epidemic Intelligence Service, Centers for Disease Control and Prevention (CDC), and the Division of Vector-Borne Infectious Diseases, National Center for Emerging and Zoonotic Infectious Disease, CDC, Atlanta, Georgia, and colleaguesreport in the October 31 issue of the CDC’s Morbidity and Mortality Weekly Report.
“Health care providers should consider Lyme disease as a cause of cardiac symptoms in patients who live in or have visited a high-incidence Lyme disease region, especially during summer and fall months and regardless of whether the patient reports erythema migrans. Additionally, health care providers should investigate the potential for cardiac involvement in patients who have other signs or symptoms of Lyme disease, particularly if they report chest pain, palpitations, lightheadedness, shortness of breath, or syncope,” the authors write.
The follow-up investigation to a December 13, 2013, report of three cases of sudden cardiac death associated with Lyme carditis included examinations of Lyme disease in seven high-incidence states. Lyme carditis was defined as acute second-degree or third-degree atrioventricular conduction block accompanying a diagnosis of Lyme disease.
During 1995 to 2013, the 121,894 cases included 1696 cases of Lyme carditis. Age-adjusted all-cause mortality (0.6% within 1 year of Lyme disease diagnosis) was lower than expected based on national rates. “Two of these deaths (0.002% of the total) were classified as suspected cases of Lyme carditis–associated mortality after review of available clinical information,” the authors write.
The two new cases were men in their 40s and 50s, both had clinical evidence of disseminated Lyme infection, and both experienced cardiac arrest within 6 weeks of Lyme disease symptom onset.
Median age for Lyme carditis was 43 years, but carditis was more common among men aged 20 to 39 years, among women aged 25 to 29 years, and among those older than 75 years than in patients aged 55 to 59 years. Most carditis (69%) was diagnosed during June through August. Patients presented with “fatigue, malaise, muscle and joint pain, shortness of breath, chest pain, and syncope,” the authors note.
“In reported cases, sudden cardiac death remains infrequent when Lyme carditis is recognized and treated with appropriate antibiotic therapy. However, two additional suspected sudden cardiac deaths associated with Lyme carditis were discovered, bringing the total number of cases identified during this investigation to five (three confirmed and two suspected). These cases highlight the public health and clinical challenge that Lyme carditis poses and the need for better primary prevention strategies,” the authors conclude.