Imaging of ventricular assist devices and their complications

CAR and CSTR Cardiac Computed Tomography (CT) Practice Guidelines: Part 2-Non-Coronary Imaging

The cardiac computed tomography (CT) practice guidelines provide an updated review of the technological improvements since the publication of the first Canadian Association of Radiologists (CAR) cardiac CT practice guidelines in 2009. An overview of the current evidence supporting the use of cardiac CT in the most common clinical scenarios, standards of practice to optimize patient preparation and safety as well as image quality are described. Coronary CT angiography (CCTA) is the focus of Part I. In Part II, an overview of cardiac CT for non-coronary indications that include valvular and pericardial imaging, tumour and mass evaluation, pulmonary vein imaging, and imaging of congenital heart disease for diagnosis and treatment monitoring are discussed. The guidelines are intended to be relevant for community hospitals and large academic centres with established cardiac CT imaging programs.

Radiology of cardiac devices and their complications

This article familiarizes the reader with several different cardiac devices including pacemakers and implantable cardioverter defibrillators, intra-aortic balloon pumps, ventricular assist devices, valve replacements and repairs, shunt-occluding devices and passive constraint devices. Many cardiac devices are routinely encountered in clinical practice. Other devices are in the early stages of development, but circumstances suggest that they too will become commonly found. The radiologist must be familiar with these devices and their complications.

Imaging of left ventricular device complications

Left ventricular assist devices have become an increasingly common life-extending therapy for patients with end-stage heart failure. These devices may be used as a bridge to transplant, destination therapy, or to recovery, providing either pulsatile or nonpulsatile support. Because of the increasing frequency of left ventricular assist device utilization and the improved short-term and long-term survival after placement, there has been a parallel increase in the radiologic imaging of patients with these devices, mandating radiologists' awareness of the manifestations of common complications, including infection, thrombosis and embolism, cannula obstruction, hemorrhage, and complications of adjacent vessels and viscera, all of which will be discussed in this pictorial essay.

Chest radiography in the ICU: Part 2, Evaluation of cardiovascular lines and other devices

OBJECTIVE

In this pictorial essay, we discuss and illustrate normal and aberrant positioning of the cardiovascular support and monitoring devices frequently used in critically ill patients, including central venous catheters, pulmonary artery catheters, left atrial catheters, transvenous pacemakers, automatic implantable cardioverter defibrillators, intraaortic counterpulsation balloon pump, and ventricular assist devices, as well as their inherent complications.

CONCLUSION

The radiographic evaluation of the support and monitoring devices used in patients in the ICU is important, because the potentially serious complications arising from their introduction and use are often not clinically apparent. Familiarity with normal and abnormal radiographic findings is critical for the detection of these complications.

Conventional radiography and computed tomography of cardiac assist devices

Patients intended for circulatory support by cardiac assist devices (CAD) usually suffer from end-stage acute or chronic heart failure. Since the introduction of CAD in 1963 by DeBakey and coworkers, the systems have gone through a substantial evolution and have been increasingly used in the intervening decades. The spectrum of CAD includes a variety of systems serving to assist the systolic function of the left ventricle, the right ventricle, or both. Conventional radiography and multislice spiral computed tomography (CT) are the most commonly used radiological techniques for imaging patients with a CAD. CT is very useful for evaluating CAD systems by using both two- and three-dimensional reconstructions of the volumetric data sets. The two techniques together allow for the comprehensive assessment of patients with devices by imaging the in- and outflow cannulae, the anastomoses, the position of the pump, as well as associated complications. A close collaboration with cardiac surgeons with expertise in the field of circulatory support is deemed necessary for adequate image interpretation. This article describes the technical diversity of the currently available CAD systems. The imaging characteristics on conventional radiography and multislice spiral CT as well as the typical complications of their use are demonstrated.

Common surgical procedures

This article illustrates some common surgical procedures. Radiologists and other physicians frequently see patients who have had one or more of these operations. We hope to illustrate with drawings and radiographs the basic purpose of the procedures and the relevant anatomy. This is not intended to illustrate or discuss the actual surgical techniques. Our intention is to illustrate one generally accepted way of performing a given type of surgical procedure. For many of these operations, there may be multiple other techniques to accomplish the same result for the patient. Some of the illustrations and text in this monograph were originally published in Radiologic Guide to Medical Devices and Foreign Bodies, edited by T.B. Hunter and D.G. Bragg, St. Louis: Mosby-Year Book, 1994.