To the Editor:

Today’s vast armamentarium of percutaneous coronary interventional devices has both simplified and complicated the procedure. While user-friendly catheters, wires and stents have allowed the seasoned interventionalist to conquer increasingly difficult anatomies, the complexity of these cases has likewise grown. Sometimes, however, a basic maneuver such as breath-holding can be of great assistance.
Deep inspiration causes caudal displacement of the diaphragm, resulting in increased distance between a stationary catheter in the aortic root and the heart. This technique is commonly used with clockwise catheter rotation to engage a superior right coronary ostium. Moreover, increased cardio-diaphragmatic separation also allows for a better-defined cardiac silhouette in left ventriculography.
During transradial catheterization or intervention, access into the ascending aorta can be problematic in the presence of an acute aortic arch to subclavian artery angle. Through downward displacement of the heart and ascending aorta, a deep breath hold frequently will improve that angulation and allow smooth entry.1 Relative negative intrathoracic pressure thus created may also aid in drawing the catheter centrally.
At times, resistance is encountered during intracoronary device advancement due to inhospitable vessel anatomy, such as tortuosity or calcification, as well as hindrance from previously deployed stent struts. We have found deep inspiration to be quite useful in these situations as well, likely due to the same mechanisms outlined above. Moreover, the caudal cardiac displacement can “straighten out” vessel anatomy and provide more parallel alignment of the advancing device with the stent lumen to avoid strut entanglement. We have found this technique particularly helpful when difficulty is encountered during advancement of high-profile devices such as the FilterWire EX retrieval catheter, both straight and angled (Boston Scientific Corporation, Natick, Massachusetts); the Export thrombectomy catheter (Medtronic Corporation, Minneapolis, Minnesota); as well as a new stent through an existing stent.
Thus this familiar, simple maneuver should not be forgotten as a useful addition to techniques and equipment such as the “buddy wire” and Wiggle Wire when obstacles are encountered. For this reason, we prefer to administer only light sedation during our cases. As an added benefit, we have found that patients frequently like the idea of active participation in their treatment.

Jack P. Chen, MD