Effect of low contrast medium-dose CTA on device sizing and access vessel assessment for TAVR

D Suchá; A Kino; K Bogart; L Molvin; X S Cheng; W F Fearon; M P Fischbein; D Fleischmann

doi:10.1016/j.ejrad.2020.108826

Effect of low contrast medium-dose CTA on device sizing and access vessel assessment for TAVR

Eur J Radiol. 2020 Mar:124:108826. doi: 10.1016/j.ejrad.2020.108826. Epub 2020 Jan 13.

Authors

D Suchá¹, A Kino¹, K Bogart¹, L Molvin¹, X S Cheng², W F Fearon³, M P Fischbein⁴, D Fleischmann⁵

Affiliations

¹ Department of Radiology, Stanford University School of Medicine, Stanford, CA, USA.
² Department of Nephrology, Stanford University School of Medicine, Stanford, CA, USA.
³ Department of Cardiovascular Medicine, Stanford University School of Medicine, Stanford, CA, USA; Department of the Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA.
⁴ Department of Cardiothoracic Surgery, Stanford University School of Medicine, Stanford, CA, USA; Department of the Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA.
⁵ Department of Radiology, Stanford University School of Medicine, Stanford, CA, USA; Department of the Stanford Cardiovascular Institute, Stanford University School of Medicine, Stanford, CA, USA. Electronic address: d.fleischmann@stanford.edu.

PMID: 32000074
DOI: 10.1016/j.ejrad.2020.108826

Abstract

Purpose: Chronic kidney disease (CKD) is prevalent in transcatheter aortic valve replacement (TAVR) candidates, leading to concerns regarding contrast medium (CM) safety. We evaluated (a) the impact of low-CM imaging on pre-TAVR measurements and (b) postcontrast acute kidney injury (PC-AKI) prevalence after dual-source computed tomography (DSCT) in TAVR candidates.

Methods: All TAVR candidates with CKD (SCr≥1.5 mg/dL) who underwent weight-based low-CM, low-pitch helical 3^rd-generation DSCT in a one-year period were included, and matched to standard-CM, non-CKD controls (N = 50). Image quality (IQ) and pre-TAVR measurement interobserver variability were evaluated. Renal function change and PC-AKI were studied in the entire TAVR cohort, irrespective of scan mode (N = 153).

Results: Low-CM in CKD (N = 25) was performed with median 68 mL CM [52-87], 90 kV [80-90] and SCr 1.6 mg/dL [1.5-1.9], and standard-CM without CKD with median 116 mL CM [96-134], 100 kV [90-110] and SCr 1.0 mg/dL [0.9-1.1](P < 0.00). Low-CM IQ was good, though lower compared with standard-CM (P < 0.02). Interobserver measurement reliability was excellent (ICCs>0.85). Interobserver-agreement was lower in low-CM, causing prosthesis size disagreement in 5/25 (kappa-0.73) versus 0/25 with standard-CM (kappa-1.00), and transfemoral eligibility disagreement in 4/25 (kappa-0.68) versus 2/25 (kappa-0.84), respectively. Mean 1-month SCr-change in the low-CM TAVR cohort (N = 35) was -1 % [-12 to +7 %] and in standard-CM (N = 118) 0 % [-8 to +10 %](P > 0.3). PC-AKI occurred in none.

Conclusion: Low-CM third-generation-DSCT achieves good IQ in TAVR candidates with CKD, and seems safe, with no apparent renal function deterioration or prevalence of PC-AKI. However, standard-CM protocols in non-CKD patients provide higher measurement reproducibility. Low-CM protocols should therefore be reserved for patients at high risk for PC-AKI.

Keywords: Acquisition protocols; Acute kidney injury; CTA; Low contrast; Low kV; TAVR.

MeSH terms

Aged, 80 and over
Aortic Valve / diagnostic imaging*
Aortic Valve / surgery
Computed Tomography Angiography / methods*
Contrast Media*
Female
Humans
Male
Observer Variation
Radiographic Image Enhancement / methods*
Reproducibility of Results
Retrospective Studies
Transcatheter Aortic Valve Replacement / instrumentation*
Transcatheter Aortic Valve Replacement / methods*

Substances

Contrast Media