Echocardiography Important in Percutaneous Intervention
Transthoracic, transesophageal and intracardiac echo guidance have advantages, disadvantages.
Echocardiography plays an important role in guiding percutaneous interventional and electrophysiology procedures.
Frank Silvestry, MD, of the University of Pennsylvania School of Medicine in Philadelphia, gave an overview of the modality at a symposium on echocardiography on Monday.
Silvestry said echocardiography is beneficial and useful in many instances where other methods, such as fluoroscopy, are limited. “There is a wide range of interventions using echo guidance, including transseptal catheterization; percutaneous balloon valvuloplasty; guidance of alcohol septal ablation for hypertrophic obstructive cardiomyopathy; myocardial biopsy; transcatheter patent foramen ovale and atrial septal defects closure; peripheral vascular interventions for atrial fibrillation; and complex percutaneous noncoronary interventions,” Silvestry said.
Three types of echo
Silvestry described the three types of echocardiography – transthoracic, transesophageal and intracardiac guidance – and noted that each is applied in a variety of interventional cardiology procedures.
Silvestry said transthoracic echo guidance is advantageous because it is readily available, portable and associated with a low relative cost and no additional risks. Furthermore, a physician is not always necessary when this method is used.
Disadvantages of transthoracic echo guidance include the limitation of use due to image quality and resolution. It may also sometimes be difficult to position certain patients for optimal windows.
Silvestry said transesophageal guidance has several advantages. “Transesophageal guidance typically provides a superior image quality,” he said. “Its multiplane capability allows precise imaging of all cardiac structures, and it is able to better guide transseptal catheterization than transthoracic echo guidance.”
Transesophageal guidance is also associated with several disadvantages, since it requires esophageal — and in some centers, endotracheal — intubation. It also requires additional sedation of the patients, involves patient discomfort and has a higher risk for esophageal trauma and aspiration.
Finally, the advantages of intracardiac echo guidance are that it also provides superior image quality and resolution and can be run by a single operator.
“This method also involves shorter procedure and fluoroscopy times and avoids general anesthesia or additional sedation,” Silvestry said. “There is also no risk of aspiration or esophageal trauma and little patient discomfort with this method.”
Disadvantages of intracardiac echo guidance are that it is more costly and there may be vascular risks in some patients. True long- and short-axis views may be difficult to achieve in some patients, Silvestry said.
Future directions
Neil Weissman, MD, of Washington Hospital Center and Georgetown University in Washington, also speaking at the symposium on echocardiography, said there are several challenges for the future.
“The challenge will be to continue developing imaging guidelines for a new technique that itself is in development,” he said. “It will be important to identify echo predictors of successful percutaneous mitral valve repair and optimize guidance for efficient valve repair in the catheterization lab. We must have a close collaboration between echocardiographer and interventionalist,” he added.