Article Type : Case Report
Authors : Yanamadala A
Keywords : Atrioventricular (AV); loss of consciousness (LOC)
A complete Atrioventricular (AV) block can present
with variable symptoms but oftentimes fatigue, dyspnea, chest pain and syncope
being the most common presentation.
A complete Atrioventricular (AV) block can
present with variable symptoms but oftentimes fatigue, dyspnea, chest pain and
syncope being the most common presentation. An uncommon presentation can
include loss of consciousness (LOC), myoclonic jerks, tonic spasms, abnormal
eye movements or frank convulsions due to decreased blood supply to the brain,
which makes it difficult to distinguish from epilepsy. Our case presents a
similar situation in which epilepsy was initially considered as the diagnosis
with no initial cardiac symptoms at presentation, later on a diagnosis of
complete AV block was made.
93 yo female with history of HTN, DM, CKD, diastolic
heart failure presented with brief involuntary generalized shaking movements of
body without loss of consciousness since 3 days. Initial physical examination
is only remarkable for patient appearing drowsy but following commands and
vitals are stable. CT head showed no acute abnormality. Neurology was consulted
for possible seizures and the patient was transferred to the neuro tele floor.
A follow up EEG did not show any abnormalities. On day 2, she was found to be
altered with generalized shaky movements and concern for seizures. Patient was
given a dose of Ativan for possible seizure with generalized shaky movements.
On the tele monitor, she had profound bradycardia with heart rate in 20-30
beats/min. Patient was given atropine with external pacing that improved heart
rate to 60’s and resolution of shaky movements and improvement in mental
status. Follow up labs including electrolytes, troponins, TSH were within
normal limits with no reversible cause was found. She has further experienced 3
similar episodes of generalized shaky movements which correspond to bradycardia
with complete AV block on tele monitor. Patient was started on dopamine
infusion with eventual placement of a dual chamber pacemaker and resolution of
symptoms.
Myoclonic jerks are one of the common misleading symptom in differentiating AV block from a seizure due to epilepsy disorder. As compared to an epilepsy related seizure, symptoms due to AV block are shorter in duration and correspond to rhythm changes on tele monitor. In patients with no significant change in mental status or post ictal changes, other diagnosis including any electrolyte abnormalities and other reversible causes for abnormal body movements should be in consideration. A 12 lead electrocardiogram should be considered in routine evaluation for a possible seizure and recurrent episodes should prompt for tele monitoring which can help in diagnosing transient AV block which could be contributing to symptoms like in our case. Early diagnosis is crucial as unrecognized transient complete AV block can have higher mortality and even sudden cardiac death. Failure to distinguish from seizure due to epilepsy disorder can lead to treatment with antiepileptic drugs (AED), which further can have cardiac side effects causing arrhythmias (Figure-1) [1-3].
Figure 1: EKG showing marked sinus bradyacardia with significant prolonged QT interval during abnormal seizure like activity.
Profound bradycardia presenting like seizure
activity is rare, but in patients who don't have altered consciousness and
presenting with this abnormal jerky movements should consider other
differentials like cardiac arrhythmias in diagnosis. Tele monitoring in these
patients will likely help in early diagnosis and improve morbidity and
mortality.