Results from a recent research study suggest that cardiac compression in the heart is more pronounced in people with a higher Haller index. However, other cardiac abnormalities may be present despite only a moderate Haller index. This reinforces the importance of getting functional (e.g., echocardiogram) testing as opposed to just structural (e.g., Haller index) testing during pectus excavatum evaluation.
This study included 28 people (only 5 were female) with an average age of about 20 years old. Everybody received a CT scan to measure a Haller index as well as an ECG to measure heart function.
The following measures were related to Haller index severity:
Compression of the right atrium of the heart
Negative portion of the P wave in V1 lead
Complete or incomplete right bundle branch block
The following measures were unrelated to Haller index severity:
Compression of the left atrium of the heart
Measures that were unrelated to Haller index may depend more on the physical shape of the deformity rather than just the severity alone.