Author + information
- ∗Departments of Medicine (Cardiovascular) and Electrical Engineering, Stanford University, Stanford, California
- †Department of Radiological Sciences, University of California, Los Angeles, Los Angeles, California
- ↵∗Address for correspondence:
Dr. Michael V. McConnell, Stanford University School of Medicine, 300 Pasteur Drive, Suite H2157, Stanford, California 94305.
echocardiography is commonly used to evaluate pericardial tamponade or constrictive pericarditis in which key findings include respirophasic changes in chamber sizes, such as right ventricular (RV) diastolic collapse and leftward shift of the interventricular septum (1). As these changes can be intermittent and subtle and with overall motion dominated by cardiac contraction, the respiratory effects can be missed, particularly by less experienced sonographers or physicians-in-training. Recognition is important to guide M-mode and longer 2-dimensional (2D) and Doppler acquisitions to evaluate respiratory effects more thoroughly (2), especially because short cine loops may not even capture these intermittent effects. An alternative 2D echocardiographic approach to facilitate recognition of respiratory changes would be to “freeze” cardiac contraction, thereby accentuating any motion due to respiration. In this iPIX, such a “respiratory-mode” approach is presented (Figs. 1 to 3⇓, Online Videos 1, 2, 3, 4, 5, and 6), in which RV collapse and septal shift are highlighted by displaying a cine loop using only image frames from a specific point in the cardiac cycle (i.e., diastole). Displaying images over the respiratory cycle, not just over the cardiac cycle, may aid in the detection of hemodynamic effects of pericardial disease.
The Departments of Medicine (Cardiovascular) and Electrical Engineering at Stanford University have MRI research collaborations with GE Healthcare, Inc. The Department of Radiological Sciences at UCLA has an MRI research collaboration with Siemens Medical Solutions USA, Inc. Dr. Wu has been supported by an NIH T32 Multidisciplinary Training Grant in Cardiovascular Imaging at Stanford (CVIS) and an American Heart Association Western States Postdoctoral Fellowship. Dr. McConnell has reported that he has no relationships relevant to the contents of this paper to disclose.
- American College of Cardiology Foundation