From the Guidelines
The most accurate method for confirming adequate placement of an Intra-Aortic Balloon Pump (IABP) on a chest X-ray (CXR) is to position the tip of the IABP 2-3 cm below the origin of the left subclavian artery, typically at the level of the carina or between the 2nd and 3rd intercostal spaces. To ensure proper placement:
- Obtain a portable anteroposterior chest X-ray immediately after IABP insertion.
- Identify the radiopaque marker at the tip of the balloon.
- Confirm that this marker is 2-3 cm distal to the aortic arch shadow.
- Verify that the entire balloon is within the descending thoracic aorta. Correct positioning is crucial because:
- If placed too high, the IABP may obstruct blood flow to the carotid or subclavian arteries.
- If placed too low, it may occlude the renal arteries or affect visceral perfusion. Improper placement can lead to complications such as organ ischemia, thrombosis, or reduced effectiveness of the IABP therapy. If the initial placement is incorrect, immediate repositioning is necessary, followed by a repeat CXR to confirm the new position, as recommended by the American Heart Association 1. Key considerations for IABP placement include:
- The IABP provides hemodynamic support for cardiogenic shock by diastolic augmentation of aortic pressure and left ventricular unloading, as described in the American Heart Association's scientific statement on mechanical circulatory support 1.
- Proper placement is essential to maximize the benefits of IABP therapy while minimizing the risk of complications.
- Regular monitoring and adjustment of IABP position may be necessary to ensure optimal therapy and prevent adverse outcomes.
From the Research
Confirming Adequate Placement of an Intra-Aortic Balloon Pump (IABP) on a Chest X-ray (CXR)
- The most accurate method for confirming adequate placement of an IABP on a CXR is by positioning the IABP tip at 2 cm above the carina, as this provides an adequate position for the IABP tip (1.5-3.5 cm distal to the origin of the left subclavian artery) in 95.3% of patients 2.
- The aortic knob is thought to be a useful radiographic landmark for the proper positioning of the IABP tip, but it may not be reliable in all cases, as 16% of patients had the IABP too close to the left subclavian artery origin when placed at the aortic knob 2.
- Malpositioning of the IABP tip can lead to major complications, including death, major limb ischemia, major IABP malfunction, balloon rupture, hemorrhage, severe renal dysfunction, stroke, and mesenteric ischemia 3, 4.
- The final position of the IABP tip on a CXR is crucial, and an acceptable position (tip seen just below the aortic arch, at T2-T5 vertebrae) is associated with lower major complication rates compared to malpositioned or severely malpositioned tips 3.
- Other studies have focused on the use of IABP in various clinical scenarios, including advanced heart failure, and have reported successful outcomes with minimal morbidity and mortality 5, 6.