Complete heart block in a 19 year old male: tick tock, tick tock!!

SESSION TITLE: Cardiovascular Case Report Posters IISESSION TYPE: Case Report PosterPRESENTED ON: Sunday, March 23, 2014 at 01:15 PM - 02:15 PMINTRODUCTION: Lyme disease is a tick-borne illness caused by spirochete Borrelia Burgdorferi. Cardiac manifestations of Lyme disease mostly include conduction abnormalities which occur weeks to a few months after the onset of infection.

CASE PRESENTATION: A 19 year old male with no past medical history presented to our emergency department (ED) with an episode of syncope while walking. Patient denied any history of chest pain, shortness of breath or previous similar episodes. The physical examination was significant for a heart rate of 33 and an Erythema Migrans rash on the back. On further history, the patient admitted to going on a hiking trip in Upstate New York few weeks ago but could not remember any tick bite. The electrocardiogram done in the ED showed complete heart block. Laboratory work up came back as normal complete blood count and serum chemistry along with negative cardiac enzymes (CK-MB and Troponin I). Patient was started on intravenous Ceftriaxone for suspected Lyme Carditis and admitted to Cardiac Intensive Care Unit for observation. ELISA and Western blot analysis revealed seropositivity for Lyme disease. Patients heart block varied from 2:1 atrioventricular (AV) Block to Mobitz Type 1 AV Block in next few days and finally resolved to a 1st degree AV Block with a PR interval of 236 ms. The echocardiogram showed normal LV systolic function with an ejection fraction of 55%. Patient remained completely asymptomatic through out the course of his hospitalization and did not require temporary venous pacing. He was discharged home with a PICC Line to complete the course of intravenous antibiotics for three weeks and to follow up with Infectious Diseases Clinic and Cardiology.

DISCUSSION: Lyme Disease is endemic in Northeastern and Mid-Atlantic regions of United States. AV conduction blocks of varying severity is the most common clinical manifestation of Lyme Carditis along with palpitations and myo-pericarditis. Lyme Cardiomyopathy has not been observed in United States, but has been reported rarely in Europe where the incidence of Lyme Carditis is lower overall, probably because of a different strain. Conduction delay in Lyme Carditis usually occurs above the bundle of His, often within the AV node. The prognosis of Lyme Carditis is excellent with resolution of the conduction abnormalities with use of antibiotics and patients rarely require a permanent pacemaker.

CONCLUSIONS: Lyme Carditis should be suspected as the cause of AV conduction block in the setting of a travel history to Lyme endemic area and Erythema Migrans rash, with or without the history of a tick bite.Reference #1: N/ADISCLOSURE: The following authors have nothing to disclose: Sameer Chadha, Geurys Rojas Marte, Bernard Topi, Gerald Hollander, Jacob ShaniNo Product/Research Disclosure Information.