Moving
Angiography Forward

Advances in laboratory construction, table design, and manifold materials have added incremental benefit over the last two decades. However, little advancement has been made in power injection systems for ventriculography and coronary arteriography. The standard contrast power injection system was useable for coronary arteriography but with off-table fixed injector settings and no or little operator input save to stop the injection by foot switch to vary the rates of injection for coronary angiography. For coronary angiography most operators preferred a manual method, turning multiple stopcocks to register pressure, aspirate, flush, and perform contrast injection. Now comes the most recent advance in coronary arteriography, the ACIST Contrast Management System (CMS). With this power injector system, the coronary multiple keyed pressure manifold is replaced with a single-connecting stopcock to the catheter and injection tubing. Catheter tip pressure is displayed at all times until the operator triggers the injection sequence. The rate of contrast injection is easily set on a sterile covered computer touch screen within the operator™s arm reach. The injection rate is also controlled by the touch sensitive operator compression trigger. By varying thumb pressure, the injection rate can rapidly be changed to meet the demands of imaging, unlike previous versions of the fixed rate remote tableside injectors. Old Habits Die Hard Although invasive cardiologists pride themselves on using new technology, the introduction of new diagnostic rather than interventional techniques in the cardiac cath lab is often met with reluctance, unless the technique is so obviously advantageous that its use is clearly a quantum step forward. As an example, one needs only reflect on slow acceptance of IVUS and angioplasty sensor guide wires as such tools in the cath lab. In comparison, rapid and immediate acceptance was clear for low profile balloon angioplasty equipment, directional atherectomy, rotablator, and certainly with modern coronary stents. Into the arena of angiography comes a new power injector applicable to coronary, left ventricular, and peripheral angiography alike. Will the advantages of this new device overcome the hand injection operator technique with the feeling of greater control? Clearly, off-table power injectors with fixed settings did not. Procedural simplification with equivalent or superior results surely leads to a better procedure. After using the ACIST injection system for 2 years, our laboratory believes this is the case. Just as the days of manual steering for cars has been supplanted by power steering with high operator satisfaction, so to has the ACIST injector system shifted our laboratory from the manual transmission of hand injection to the automatic transmission of variable rate operator-triggered power coronary injection technique. The ACIST injector system is a logical advance in current angiographic methodology. There is no reason to use a complex multivalved manifold when an equivalent and simpler injection system can deliver a precise quantity of contrast, at a rate controlled precisely by the operator. Our laboratory has become exclusively an ACIST injection system user. Our clinical studies have demonstrated the advantages of this system by comparisons of coronary angiography using 4 and 6 French catheter(s) with and without the ACIST injector and with and without manual injection. Image quality has been maintained and is equal or superior to 6 French imaging with a lower delivery of contrast to the patient(s).1 With the multiple patient contrast saving system in place, cost reductions for most laboratories can be realized. The ACIST injector also offers versatility to the operator for different kinds of angiography at the same setting. The operator can rapidly change injection settings from coronary arteriography to left ventriculography to aortography and then to peripheral angiography with precise specifications for the rate of injection, volume, and pressure. These variables can be preset or automatically adjusted by the operator on the touch screen. In our laboratory, the versatility of the ACIST injector system as compared to previous off table injection systems has been widely appreciated by all operators, technicians, and nurses who find that the ACIST method is superior. In this supplement on updates in coronary arteriography, the reader will learn more about the ACIST system, its advantages supplanting the current hand injection methodology, bringing power steering to the cardiac cath lab. The reader will also find useful information on the challenges faced by labs considering implementation of the ACIST injector in their facility.

References 1. Khoukaz S, Kern MJ, Bitar SR, Azrak E, Eisenhauer M, Wolford T, El-Shafei A.  Coronary Angiography Using 4 Fr Catheters With Acisted Power Injection:  A Randomized Comparison to 6 Fr Manual Technique and Early Ambulation.  Cathet Cardiovasc Interven 2001; 52:393-398.