Clinical and economic outcomes of pharmacological stress tests in patients with a history of COVID-19.

BACKGROUND: Despite millions of COVID-19 cases in the United States, it remains unknown whether a history of COVID-19 infection impacts the safety of pharmacologic myocardial perfusion imaging stress testing (pharmacologic MPI). HYPOTHESIS: The aim of this study was to assess if a prior COVID-19 infection was associated with a higher risk of complications during and following pharmacologic MPI testing. METHODS: This retrospective cohort analysis included 179 803 adults (≥18 years) from the PharMetrics® Plus claims database who underwent pharmacologic MPI between March 1, 2020 and February 28, 2021. Patients with a history of COVID-19 infection (COVID-19 group) were compared with propensity-score matched no-COVID-19 history group for reversal agent use, 30-day resource use, and post-MPI cardiac events/procedures. RESULTS: The most commonly used stress agent was regadenoson (91.7%). The COVID-19 group (n = 6372; 3.5%) had slightly higher: reversal agent use (difference 1.13% [95% confidence interval [CI]: 0.33, 1.92]), all-cause costs (difference USD $128 [95% CI: $73-$181]), and office visits (81.5% vs. 77.0%) than the no-COVID-19 group. Prior COVID-19 infection did not appear to impact subsequent cardiac events/procedures. CONCLUSIONS: COVID-19 history was associated with slightly higher reversal agent use, all-cause costs, and office visits after pharmacologic MPI; however, the differences were not clinically meaningful. Concerns for use of stress agents in patients with prior COVID-19 do not appear to be warranted.

Influence of cardiac stress protocol on myocardial perfusion imaging accuracy: The role of exercise level on the evaluation of ischemic burden.

BACKGROUND: Some specifics of cardiac stress protocols, i.e., stressor used or exercise level achieved, may impact myocardial perfusion imaging (MPI) accuracy. METHODS: Four-hundred and seventy-five patients were submitted to MPI and coronary angiography. MPI was performed after exercise (303 patients) or dipyridamole stress (172 patients). A coronary stenosis ≥70% was considered significant. In case of exercise test, a peak heart rate (HR) <85% of the maximal age predicted was considered submaximal and categorized as follows: >75% and <85% ("Group 1"); <75% ("Group 2"). RESULTS: At coronary angiography, 312/475 (66%) patients showed significant stenosis. In the overall population, MPI showed a high accuracy in unmasking significant coronary stenosis, independently of the stress protocol adopted (AUC .76 for exercise vs .78 for vasodilator; P = NS). However, in case of an exercise stress test, a significant interaction between peak %HR and MPI diagnostic power was evident. While an elevated accuracy was still maintained in "Group 1" patients (AUC .79; P vs maximal exercise = NS), a significant drop was demonstrated in "Group 2" patients (AUC .66; P vs maximal exercise = .012, and P vs "Group 1" = .042). CONCLUSIONS: The accuracy of MPI is not influenced by the stress protocol adopted. Exercise MPI maintains an elevated accuracy as long as the %HR remains >75%.