Introduction
One essential component of the initial patient workup for pulmonary arterial hypertension (PAH) is the need to obtain a radiographic assessment of the lungs. This is done in conjunction with a detailed patient history, ECG, and physical exam. A standard chest X-ray can reveal essential physical details about the lungs, heart and pulmonary vasculature.
Specifically, the chest X-ray can indicate the following:
- Enlarged pulmonary arterial “shadows”
- Attenuation of peripheral pulmonary vascular markings (also referred to as “pruning”)
- Right ventricular enlargement
- Presence of interstitial lung fibrosis, which can contribute to development of pulmonary hypertension
- Pulmonary venous congestion, indicative of possible pulmonary veno-occlusive disease or pulmonary venous hypertension
- Hyperinflation (COPD)
Limitations of Chest X-Ray in the Diagnosis of Pulmonary Hypertension
One limitation of the use of x-ray is that a clinician cannot determine the presence of pulmonary hypertension. Additionally, x-rays can only provide clues for the possibility of pulmonary hypertension.
Examples of Chest X-Ray in a Patient with Pulmonary Arterial Hypertension
The images depicted in Figure 1 are characteristic of a patient with pulmonary hypertension. The enlargement of the right ventricle is particularly notable here. As pulmonary vascular resistance increases, the required workload elevation in the right ventricle contributes to hypertrophy of the ventricular muscle.
Reproduced with permission from McLaughlin VV et al. J Am Coll Cardiol 2009;53:1573-1619.
Figure 2 is an additional example of a chest x-ray; note the “water bottle” heart shape which is often seen in these patients. This, however, is not a singular diagnostic criterion of PAH.
Reproduced with permission from Kabbani SS and M LeWinter: Cardiology.MH Crawford et al.(eds);2001.
Chest X-ray can also reveal evidence of pulmonary fibrosis, as shown in the example (Figure 3). The evidence is noted by the extensive increase in interstitial markings with distortion of the underlying parenchymal architecture, as seen in the image.
Image courtesy of Dr. Frank Gaillard. Idiopathic pulmonary fibrosis. Radiopaedia.org.
http://radiopaedia.org/cases/idiopathic-pulmonary-fibrosis-5. Accessed September 30, 2013.
Summary
- A chest X-ray is a useful diagnostic tool and an adjunct to other more definitive tests.
- An X-ray can illuminate specific changes in the lung vasculature and heart structure, which may lead a health care provider to seek more definitive information regarding pulmonary vascular pressures.
- A chest X-ray can reveal signs of emphysema or pulmonary fibrosis, which can contribute to development of pulmonary arterial hypertension.
References
1. McLaughlin VV et al. J Am Coll Cardiol 2009;53:1573-1619.
2. Kabbani SS and M LeWinter: Cardiology. MH Crawford et al.(eds);2001.
3. Dr. Frank Gaillard. Idiopathic pulmonary fibrosis. Radiopaedia.org. http://radiopaedia.org/cases/idiopathic-pulmonary-fibrosis-5. Accessed September 30, 2013.
|