Intracardiac echocardiography without fluoroscopy: potential of a balloon-tipped, flow-directed ultrasound catheter.

Intracardiac echocardiography is a technique that uses catheter-based ultrasound transducers placed within the heart to image cardiac structures. One disadvantage to this technique is that it requires fluoroscopy for catheter placement. This study was performed to evaluate a prototype balloon-tipped, flow-directed catheter for use during intracardiac echocardiography in seven dogs. With the balloon deflated, the catheter could not be successfully advanced without fluoroscopy. Even with fluoroscopic imaging, catheter advancement was often difficult. With the balloon inflated, it could easily be passed into the pulmonary artery without fluoroscopy in 12 of 14 attempts. Images of the cardiac chambers, valves, and pulmonary artery could be obtained. In conclusion, use of a balloon-tipped, flow-directed catheter for intracardiac echocardiography and pulmonary artery imaging can be performed without the use of fluoroscopy. With continued refinements, such as enhancement of the visual field, intracardiac echocardiography could possibly be performed at the bedside to assess cardiac function or assist with interventional procedures.