HCPCS Level II code C8924 describes a transthoracic echocardiography (2D) study performed with contrast, or a study performed without contrast followed by with contrast, including real-time image documentation and m-mode when performed, intended for follow-up or limited evaluations; service type: diagnostic cardiac imaging (contrast-enhanced transthoracic echocardiogram); typical site of service: outpatient imaging center, hospital outpatient department, or cardiology clinic.