Complete heart block due to diphtheritic myocarditis in the present era
The second patient was an 8-year-old boy who presented with complaints of fever and cough of 10 days duration along with progressive neck swelling. He developed bulbar symptoms including nasal regurgitation of food and nasal twang after six days into the illness. Since the onset of neurological symptoms he was admitted in a tertiary pediatric hospital with a provisional diagnosis of diphtheria based on presence of extensive membrane formation in both tonsils and pharynx. Treatment given to him included penicillin, erythromycin, and diphtheria antitoxin although no positive culture reports were available. On the tenth day of illness he developed significant bradycardia and was referred to our center as a suspected case of diphtheria myocarditis. Clinical examination revealed cervical lymphadenopathy, features of bulbar palsy and generalized diminished tendon reflexes in addition to bradycardia. ECG showed CHB with a ventricular escape rate of 40 beats per minute; hence a temporary pacemaker was inserted immediately. He had severe biventricular dysfunction (LVEF = 20%) and moderate mitral regurgitation (MR) and tricuspid regurgitation (TR) by echocardiography. After admission he was continued on antibiotics and antiserum and other supportive measures. His blood work up was unremarkable except for mild leukocytosis. During the hospital stay he had two episodes of accelerated junctional rhythm lasting few minutes and subsided on its own. On day six of admission his ECG reverted to normal sinus rhythm after an intermediate few hours of atrial flutter with variable conduction. He continued to have a favorable course in hospital with LVEF showing remarkable improvement to 50% along with improvement in neurological symptoms and hence was discharged after 22 days of hospital stay.