Quantitative Clinical Nuclear Cardiology, Part 1: Established Applications

Abstract

Learning Objectives: On successful completion of this activity, participants should be able to (1) know the basics of how quantitative parameters of relative left ventricular myocardial perfusion are measured and used clinically to differentiate patients with normal versus abnormal distributions; (2) know the basics of how quantitative parameters of left ventricular myocardial global and regional function is measured and used clinically to differentiate patients with normal versus abnormal function; and (3) describe and know how to use clinically nonperfusion quantitative parameters obtained from perfusion studies to modify the likelihood of the presence and extent of coronary artery disease in patients. Financial Disclosure: Dr. Moody is an employee of Invia. Dr. Slomka receives grants from the National Institutes of Health and Siemens Medical Systems and receives software royalties from Cedars-Sinai. Dr. Germano receives royalties from most nuclear medicine companies. Dr. Ficaro is an employee of Invia. Dr. Garcia receives grants from Syntermed and GE Healthcare and receives royalties from Syntermed. The authors of this article have indicated no other relevant relationships that could be perceived as a real or apparent conflict of interest. CME Credit: SNMMI is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to sponsor continuing education for physicians. SNMMI designates each JNM continuing education article for a maximum of 2.0 AMA PRA Category 1 Credits. Physicians should claim only credit commensurate with the extent of their participation in the activity. For CE credit, SAM, and other credit types, participants can access this activity through the SNMMI website (http://www.snmmilearningcenter.org) through November 2022. SPECT myocardial perfusion imaging has attained widespread clinical acceptance as a standard of care for patients with known or suspected coronary artery disease. A significant contribution to this success has been the use of computer techniques to provide objective quantitative assessment in the standardization of the interpretation of these studies. Software platforms have been developed as a pipeline to provide the quantitative algorithms researched, developed and validated to be clinically useful so diagnosticians everywhere can benefit from these tools. The goal of this continuing medical education article (part 1) is to describe the many quantitative tools that are clinically established and, more importantly, how clinicians should use them routinely in interpretation, clinical management, and therapy guidance for patients with coronary artery disease.

A highly predictive cardiac positron emission tomography (PET) risk score for 90-day and one-year major adverse cardiac events and revascularization

“…The ischemic burden was determined using the difference between the summed rest and summed stress scores from 17 segments and then dividing this by 68. 24 As part of the electronic generated PET/CT report, the risk of a short-term ischemic event (low, moderate, or high) was recorded by the reading cardiologist. While the cardiologist would make this assessment using the measured PET/CT parameters and clinical characteristics, there was no set algorithm or protocol for determining these risk levels.…”

Multimodality cardiovascular imaging in hypertension

“…Radionuclide imaging with single photon emission computed tomography (SPECT) or positron emission tomography (PET) is widely used in the diagnosis and management of patients with hypertension. Nuclear imaging tools are inherently digital and quantitative, encompassing measurements of myocardial perfusion, right and left ventricular (LV) function, synchrony of contraction, myocardial substrate metabolism, innervation, and inflammation [30,31].…”

“…Electrocardiography gating is advised in all SPECT and PET protocols to assess LV function parameters and perfusion variables. Automatic computer-based methods quantify indices of global function, including LVEF, EDV, ESV and transient ischemic dilation (TID), myocardial mass, and diastolic function at stress and rest [30].…”

“…( [30]. Quantitation of ventricular function, myocardial volume and mass with gated SPECT myocardial perfusion imaging (MPI) is based on the automatic detection of endocardial and epicardial surface points across the cardiac cycle in three dimensions or by the principle of constant mass across the cardiac cycle for improved contour detection [32][33][34][35].…”

Adding value to myocardial perfusion scintigraphy: A prediction tool to predict adverse cardiac outcomes and risk stratify

“…Both clinical risk factors with derived composite scores as well as automated quantitative SPECT variables have separately been well known to have association with cardiovascular outcomes. Earlier studies either generated risk stratification models for cardiovascular outcomes using composite scores derived solely from clinical variable 9 or have utilized the predictive potential of quantitative MPI technique for evaluation of presence and severity of coronary disease and prediction of cardiac events 10 There are studies regarding the prognostic value of SPECT MPI in patients with individual risk factors, but recently there have been studies that have combined clinical and imaging variables to generate risk stratification tools. [11][12][13] CRAX2MACE builds off previous work that examined outcomes on a longer-term interval.…”