Treatments

The procedure requires placement of an intra-aortic balloon catheter into an artery, usually in the groin (the femoral artery) and then advanced into the largest artery in your body, the aorta. Next, the intra-aortic balloon catheter is connected to a machine, called an IABP. The IABP is used to control the inflation/deflation and timing, so that the intra-aortic balloon will inflate when the heart muscle relaxes and deflate just before the heart pumps again. This process is called “counterpulsation.”
The IABP, which is at the bedside, inflates the intra-aortic balloon within the aorta when the heart is relaxed. This allows the heart to receive more oxygen-rich blood without working so hard. Then, just before the heart gets ready to pump this oxygenated blood, the pump deflates the intra-aortic balloon. This creates a drop in the pressure within the aorta, assisting the heart by reducing the amount of work on the heart, so the heart can pump the blood more easily throughout the body.
Once the heart stabilizes and can function properly on its own, the intra-aortic balloon catheter is removed, and pressure is applied to the insertion site to stop bleeding.
Although the IABP was first used for surgical patients, the pump can now be used along with interventional cardiology procedures and medical therapy (medications). The IABP is typically used for the following situations:

• During emergency situations, including heart attack and heart failure.
• During severe angina episodes.
• Before, during, or after open-heart surgery (in certain patients only).
• Before, during, or after balloon angioplasty (in certain patients only).
• During the waiting period for a donor heart for heart transplantation.

Support during high-risk percutaneous transluminal coronary (balloon) angioplasty, rotoblator procedures, and coronary stent placement.

The device consists of a catheter introduced via the femoral artery, which extends retrogradely to the proximal descending thoracic aorta. A balloon is located at the end of the catheter, spanning 26-28cm in length, which is rapidly inflated at the beginning of diastole and rapidly deflated at the end of diastole. The balloon is inflated with carbon dioxide.
As the balloon forcibly inflates it displaces blood both forwards and backwards, known as diastolic augmentation. As such it provides not only additional forward momentum to the blood in the distal descending aorta but more importantly increases perfusion to the vessels arising from the arch of the aorta, most importantly the coronary arteries which are perfused primarily during diastole 1-2.
This has a dual effect: firstly it decreases left ventricular afterload, decreasing myocardial(heart muscle) oxygen requirements, and secondly increases myocardial perfusion (during diastole)

The Pump

The IABP is a polyethylene balloon mounted on a catheter, which is generally inserted into the aorta through the femoral artery in the leg. The pump is available in a wide range of sizes (2.5 cc to 50 cc) that will fit patients of any age and size. The balloon is guided into the descending aorta, approximately 2 cm from the left subclavian artery. At the start of diastole, the balloon inflates, augmenting coronary perfusion. At the beginning of systole, the balloon deflates; blood is ejected from the left ventricle, increasing the cardiac output by as much as 40 percent and decreasing the left ventricular stroke work and myocardial oxygen requirements. In this manner, the balloon supports the heart indirectly.
The balloon is inflated with helium, an inert gas that is easily absorbed into the bloodstream in case of rupture. Inflation of the balloon can be triggered according to the patient’s electrocardiogram, their blood pressure, a pacemaker (if they have one), or by a pre-set internal rate.

The Console

The IABP is driven by the balloon pump console. The operating controls are located on a touch pad below the display monitor and can be programmed to produce rates as high as 140 beats per minute. The on-board battery provides power for up to 2 hours.

Technique:

Device insertion
In modern usage, intra-aortic balloon counterpulsation is performed with a polyethylene balloon mounted on a flexible catheter positioned 1-2 cm below the origin of the left subclavian. The shaft of the balloon catheter contains 2 lumens: one allows for gas exchange from console to balloon; the second is used for catheter delivery over a guide wire and for monitoring of central aortic pressure after installation.
Balloon inflation is performed using helium, which, owing to its low density, can be rapidly exchanged through the tubing and catheter to allow for rapid balloon inflation and deflation during the cardiac cycle.
Insertion is generally performed via either one of the femoral arteries using a standard percutaneous Seldinger technique over a 0.030-inch guidewire provided with the balloon catheter.
The device catheter can be introduced via a sheath. A sheathless approach can also be used in patients with peripheral vascular disease. The sheathless method has been shown to reduce limb ischemia, but the risk of infection and minor bleeding is increased with this method.
McBride et al described the insertion of an intra-aortic balloon pump (IABP) catheter via the axillary artery to allow for more patient mobility. This is performed via a cutdown, often using a 6-12 mm GoreTex or Dacron sleeve sewn onto the axillary artery to facilitate introduction of the device.
An IABP device can also be inserted via the brachial artery or subclavian artery or, during open-heart surgery, directly into the ascending or thoracic aorta.

Initial set-up and troubleshooting

Following installation, the balloon catheter is connected to the console and the system is purged with helium. The central lumen of the catheter is connected to pressure tubing and a pressure transducer to allow for monitoring of central aortic pressure.
Heparin should be given as a bolus and continuous infusion to maintain a partial thromboplastin time (PTT) of 60-80 seconds or an activated clotting time (ACT) of 1.5-2.0 times normal.
An appropriately timed IABP will effectively lower impedance to left ventricular (LV) ejection and augment diastolic pressure. However, improper timing can lead to inefficient LV support or counteract the intended purpose of therapy.