When frantic parents arrive at the emergency room and report that their infant experienced a frightening combination of symptoms including a prolonged lapse in breathing, change in color or muscle tone, or coughing or gagging, clinicians likely will describe the episode as an apparent life-threatening event (ALTE). Yet, it can be a frustrating conclusion because often these symptoms have resolved by the time the patient arrives at the ER, and the clinician is left to discern the exact cause.
The most common underlying diagnoses related to ALTEs are gastroesophageal reflux and upper respiratory illness. Clinicians also consider cardiac causes, but no standardized method is used to evaluate patients with ALTEs, especially with regard to electrocardiograms (ECGs) as a diagnostic tool. An ECG measures a heart’s electrical activity and generates a graphic representation, or tracing, that can indicate heart-related conditions.
A study team of physicians from The Children’s Hospital of Philadelphia’s Department of Pediatrics and Cardiac Center wanted to determine the prevalence of cardiac diagnoses in children who present with ALTEs and how often ECGs are used.
“This is the largest study of its kind and the first multicenter study looking into the evaluation of cardiac etiologies of ALTEs,” said Matthew D. Elias, MD, a CHOP pediatric cardiology fellow physician. “Hopefully it will contribute to the knowledge base of those providing for patients with ALTEs of what their institutions are using as a diagnostic workup for these patients and what other institutions are doing.”
Dr. Elias conducted the study with V. Ramesh Iyer, MD, MRCP, an attending electrophysiologist, and Meryl S. Cohen, MD, an attending cardiologist and director of the echocardiography laboratory. They reported their findings in the April issue of Pediatric Emergency Care.
The study team analyzed data from the Pediatric Health Information System database and found that ALTEs are relatively common, accounting for 2,179 hospital encounters at 43 children’s hospitals during a 15-month period from 2009 until 2010. Their analysis showed that 16 percent of these patients (355) had a cardiac diagnosis; however, due to the database’s limitations, the study team could not determine that cardiac pathology was related to the ALTEs.
The study’s main finding was that the hospitals had a wide range in the use of diagnostic ECGs, which highlights the absence of a systematic approach to ALTEs.
“Some hospitals almost never ordered an ECG, and others almost 100 percent of the time ordered an ECG,” Dr. Elias said. “On average, ECGs were ordered 43 percent of the time.”
When the study team looked deeper into the demographic information to determine any reasons why some patients with ALTEs would receive an ECG and some would not, the one statistically significant finding was that those patients who were older at presentation were more likely to have an ECG ordered.
“ALTEs typically present within the first three months of life, and if a patient were to present later on at several months of age, we think that those providing for the patients might expand their differential diagnosis and start suspecting a possibility of a cardiac disease,” Dr. Elias said.
This study raises a larger question for future research of whether or not ECGs could be helpful as a screening tool to detect or rule out particular cardiac diagnoses for patients with ALTEs.