Additional information | Anatomy of the cardiovascular system | Anatomy

Additional information

Box for Kaposi sarcoma versus Bartonella henselae: Kaposi sarcoma is a malignant proliferation of endothelial cells associated with HHV 8 virus. Bacillary angiomatosis is an infectious, vasoproliferative disorder caused by Bartonella henselae. Both conditions are seen in immunocompromised and HIV-positive patients. Both can present as purple-to-red, raised nodules or plaques involving the skin and internal organs. You can distinguish them by histopathology: bacilli are seen only in bacillary angiomatosis, while spindle cells are seen in Kaposi sarcoma.
Cardiac silhouette On an antero-posterior (AP) or postero-anterior (PA) chest radiograph, the borders of the heart have common landmarks:
1. Right border: Formed by the right atrium, which lies between the SVC and IVC.
2. Left border: Formed by the left ventricle and a portion of the left auricle.
3. Anterior surface (sternocostal surface): Mainly the right ventricle (not seen on AP view).
4. Inferior border: Formed by a combination of the right and left ventricles.
Aortic knob
On a normal chest radiograph, the aortic knob should be visible around the level of T3 to T4, just lateral to the carina. In patients with an aortic aneurysm, this region may contribute to a “widened mediastinum.”
Costocardiac & costophrenic angles: The costocardiac angles (as well as the costophrenic angles) should be sharp and well defined when there are no significant effusions or pulmonary edema. If these angles are blunted or obscured, consider fluid in the lung or a mass obstructing the view. If the cause isn’t clear from the patient’s presentation, additional imaging with a chest CT may sometimes be warranted.

Box for Kaposi sarcoma versus Bartonella henselae: Kaposi sarcoma is a malignant proliferation of endothelial cells associated with HHV 8 virus. Bacillary angiomatosis is an infectious, vasoproliferative disorder caused by Bartonella henselae. Both conditions are seen in immunocompromised and HIV-positive patients. Both can present as purple-to-red, raised nodules or plaques involving the skin and internal organs. You can distinguish them by histopathology: bacilli are seen only in bacillary angiomatosis, while spindle cells are seen in Kaposi sarcoma.
Cardiac silhouette On an antero-posterior (AP) or postero-anterior (PA) chest radiograph, the borders of the heart have common landmarks:
1. Right border: Formed by the right atrium, which lies between the SVC and IVC.
2. Left border: Formed by the left ventricle and a portion of the left auricle.
3. Anterior surface (sternocostal surface): Mainly the right ventricle (not seen on AP view).
4. Inferior border: Formed by a combination of the right and left ventricles.
Aortic knob
On a normal chest radiograph, the aortic knob should be visible around the level of T3 to T4, just lateral to the carina. In patients with an aortic aneurysm, this region may contribute to a “widened mediastinum.”
Costocardiac & costophrenic angles: The costocardiac angles (as well as the costophrenic angles) should be sharp and well defined when there are no significant effusions or pulmonary edema. If these angles are blunted or obscured, consider fluid in the lung or a mass obstructing the view. If the cause isn’t clear from the patient’s presentation, additional imaging with a chest CT may sometimes be warranted.