Sustainable Resumption of Cardiac Catheterization Laboratory Procedures, and the Importance of Testing, During Endemic COVID-19

Dombrády Ö, Csobay-Novák C, Merkely B, Szilveszter B. Coronary CTA Amidst the COVID-19 Pandemic: A Quicker Examination Protocol with Preserved Image Quality Using a Dedicated Cardiac Scanner

There has been an ongoing debate on the means to minimize the time patients spend at health care providers during the COVID-19 pandemic. We propose a strategy relying solely on intravenous (i.v.) beta-blocker administration for heart-rate (HR) control prior to coronary CT angiography (CCTA). We aimed to assess a potential difference in CCTA image quality (IQ) after implementation of a modified strategy compared to our standard protocol of oral premedication during the first wave of COVID-19. We analyzed CCTA examinations conducted one year before (n = 1511) and after (n = 1064) implementation of this new regime. Examinations were performed both on our 256-slice multidetector CT (MDCT) and dedicated cardiac CT (DCCT) scanners. We used a four-point Likert scale (excellent/good/moderate/non-diagnostic) for IQ assessment of the coronaries. We detected a significant increase in mean HR during examinations on both CT scanners (MDCT: 62.4 ± 10.0 vs. 65.3 ± 9.7, p < 0.001; DCCT: 61.7 ± 15.2 vs. 65.0 ± 10.7, p < 0.001). The rate of moderate/non-diagnostic IQ significantly increased on the MDCT (192/1005, 19.1% vs. 144/466, 30.9%, p < 0.001), while this ratio did not change significantly on the DCCT (62/506, 12.3% vs. 84/598, 14.0%, p = 0.38). The improved temporal resolution of DCCT allows the stand-alone use of i.v. premedication with preserved IQ; hence, the duration of visits can be shortened.

DIAGNOSTIC STRATEGIES FOR ENDEMIC CORONAVIRUS DISEASE 2019 (COVID-19): RAPID ANTIGEN TESTS, REPEAT TESTING, AND PREVALENCE BOUNDARIES

CONTEXT

- Coronavirus disease 2019 (COVID-19) rapid antigen tests generate intrinsically fast, inherently spatial, and immediately actionable results. They quickly confirm COVID-19, but weakly rule out infection. Test performance depends on prevalence and testing protocol. Both affect predictive values.

OBJECTIVES

- To use original mathematics and visual logistics for interpreting COVID-19 rapid antigen test performance patterns, gauge the influence of prevalence, and evaluate repeated testing.

DESIGN

- Mathematica and open access software helped graph relationships, perform recursive computations, and compare performance patterns. PubMed retrieved articles addressing endemic COVID-19.

RESULTS

- Tiered sensitivity/specificity comprise: T1) 90%/95%; T2) 95%/97.5%; and T3) 100%/≥99%, respectively. Performance of self- and home antigen tests with Food and Drug Administration Emergency Use Authorization peaks in low prevalence. Fall-off in performance appears with increasing prevalence because suboptimal sensitivity creates false negatives. The rate of false omissions limits clinical use because of prevalence boundaries based on tolerance for risk. Mathematical analysis supports testing twice to improve predictive values and extend prevalence boundaries nearly to levels of herd immunity.

CONCLUSIONS

- COVID-19 is quickly becoming endemic. Suboptimal sensitivity of rapid antigen tests limits performance in high prevalence. Risk of contagion in packed spaces (e.g., airplanes) might be avoided with dual testing 36 hours apart, allowing time for viral load to increase. Awareness of community prevalence and proof of improved performance with repeated testing will help manage COVID-19 risk, while meeting rapid decision-making needs for highly contagious and new variants (e.g., Delta). New COVID-19 variants call for high quality, low cost, readily accessible, fast, user friendly, and ubiquitous point-of-care testing.