Noninvasive Assessment of Right Ventricular Function: Will There Be Resurgence in Radionuclide Imaging Techniques?

Abstract

Right ventricular (RV) function is increasingly being recognized as an important prognostic marker in multiple cardiopulmonary disease states, including congestive heart failure, pulmonary arterial hypertension, and chronic obstructive pulmonary disease. Accurate and reproducible measures of RV function, although technically challenging, are highly relevant in the clinical setting. Radionuclide techniques (eg, first-pass radionuclide angiography for quantifying RV systolic function) were developed nearly 40 years ago. More recently, MRI and transthoracic echocardiography have become the diagnostic imaging techniques of choice for the noninvasive evaluation of RV function. However, developments in single photon emission computed tomography (SPECT), positron emission tomography (PET), and hybrid SPECT/CT and PET/CT systems have greatly improved the image quality and contrast resolution of radionuclide imaging of the heart, allowing for coregistered physiologic and anatomical information of the right ventricle in three dimensions. These improvements in cardiac imaging provide new opportunities for assessing RV myocardial perfusion, function, and anatomy in the same setting. Such imaging approaches may in the future provide assistance with proactive disease management, including early diagnosis of impending RV dysfunction in high-risk patients and for guiding decisions to initiate and/or modify treatments.

Comparison of 18F‐FDG uptake by Right Ventricular Myocardium in Idiopathic Pulmonary Arterial Hypertension and Pulmonary Arterial Hypertension Associated with Congenital Heart Disease

“…Both techniques express the results as the RV/LV FDG ratio. [1321] Arguably, SPECT is more widely available and so our observations have broader utility. The relatively small number of patients studied is also a limitation but the cohort is one of the largest studied to date.…”

“…[21] RV FDG uptake showed a positive correlation with PVR and correlated negatively with the 6MWT, both prognostic markers in IPAH. This may indicate that RV FDG uptake provides additional information in IPAH.…”

Right Ventricular Adaptation and Failure in Pulmonary Arterial Hypertension

“…RV mass and end-diastolic wall thickness 41,42 and the LV septal-to-free wall curvature ratio 43 each correlate well with mPAP. Tagged MRI can be used to measure segmental RV motion in a three-dimensional manner and identifies significant interventricular dyssynchrony in PAH due to RVH and delayed RV conduction 44,45 . Features of RV adaptation and failure detectable on MRI are summarized in Table 3.…”

“…Positron emission tomography (PET), and hybrid studies with SPECT/CT and PET/CT are invaluable in measuring RV metabolism and perfusion in vivo and permit simultaneous co-registration of biochemical and anatomic or functional information. RVH, with increased chamber mass and coronary blood flow, augments radiotracer delivery, making it possible to image the RV, which is often not possible in patients who lack RVH 45 . In PAH there is evidence of RV ischemia (reduced flow reserve) 54 .…”

Accuracy and variability of right ventricular volumes and mass assessed by dual-source computed tomography: influence of slice orientation in comparison to magnetic resonance imaging

“…Alternative noninvasive imaging techniques for quantifying ventricular function are radionuclide ventriculography and gated single photon emission computed tomography (SPECT). These techniques, though, are of limited availability, provide poor spatial resolution and are associated with exposing the patient to radiation [28].…”