Complete heart block due to diphtheritic myocarditis in the present era
A 10-year-old boy had presented with history of fever of 10 days duration along with progressive swelling of neck. Three days prior to admission he also developed difficulty in swallowing with nasal regurgitation of food associated with progressive dyspnea and orthopnea. There was no reliable history of adequate immunization against diphtheria. On examination his pulse rate was 42 beats per minute, regular, low volume with blood pressure of 86/64 mmHg, and there was bilateral cervical lymphadenopathy. His clinical assessment revealed a membrane over right tonsil and posterior pharyngeal wall with features of bulbar palsy as well. Electrocardiogram (ECG) showed CHB with a ventricular escape rate of 40. A temporary transvenous pacemaker was inserted immediately in view of the low heart rate. An emergency echocardiogram showed global hypokinesia with left ventricular ejection fraction (LVEF) of 15%. His investigations showed raised white blood cell (WBC) count of 38100/mm3 with neutrophilic preponderance as well as elevated renal parameters. Although his throat swab cultures and blood cultures were sterile, a provisional diagnosis of bulbar diphtheria with myocarditis was made and he was started on intravenous erythromycin and crystalline penicillin along with diphtheria antiserum. Although he was afebrile throughout the hospital stay, he continued to be in CHB and developed progressive hypotension, which was treated with inotrops. He sustained a ventricular tachycardia (VT) on day six of admission, which was refractory, and he expired on the same day due to progressive cardiogenic shock.