Article Impact Level: HIGH Data Quality: STRONG Summary of Circulation, CIRCULATIONAHA.123.066498. https://doi.org/10.1161/CIRCULATIONAHA.123.066498 Dr. Martin Reindl et al.
Points
- A prospective, randomized non-inferiority trial conducted at two Austrian heart centers compared CMR (cardiac magnetic resonance) and CT (computed tomography) as imaging modalities for guiding transcatheter aortic valve replacement (TAVR) in patients with severe symptomatic aortic stenosis.
- The study addressed the limitation of iodinated contrast media use in CT for TAVR planning, especially for patients with chronic kidney disease (CKD).
- The primary outcome, defined according to the Valve Academic Research Consortium-2 criteria, assessed implantation success, procedural mortality, prosthetic valve positioning, and valve performance.
- The results showed that CMR-guided TAVR was non-inferior to CT-guided TAVR regarding device implantation success, with a low absolute risk difference between the two groups.
- This research supports using CMR as a safe and effective alternative to CT for TAVR planning, expanding options for clinicians and patients in transcatheter aortic valve replacement.
Summary
In transcatheter aortic valve replacement (TAVR), where precise imaging is crucial, computed tomography (CT) has conventionally been the modality of choice. However, a substantial proportion of TAVR candidates suffer from chronic kidney disease (CKD), making using iodinated contrast media for CT scans problematic. This research seeks to address this challenge by investigating the potential of cardiac magnetic resonance (CMR) as a viable alternative to CT for TAVR planning. It is important to note that, before this study, randomized data comparing the efficacy of CMR-guided TAVR to the CT-guided approach were notably absent.
To address this knowledge gap, an investigator-initiated, prospective, randomized, open-label, non-inferiority trial was conducted at two Austrian heart centers. This trial included patients with severe symptomatic aortic stenosis who met specific inclusion and exclusion criteria. The latter criteria encompassed contraindications to CMR, CT, or TAVR, a life expectancy of less than one year, and CKD stages 4 or 5. Patients were randomly assigned to either CMR-guided or CT-guided TAVR planning. The primary outcome measure was defined according to the Valve Academic Research Consortium-2 definition of implantation success, which assessed procedural mortality, the accuracy of prosthetic valve placement, and the proper performance of the prosthetic valve. This study employed a non-inferiority design with a predetermined risk difference margin of 9%.
The findings from this study, which spanned from September 11, 2017, to December 16, 2022, revealed that 380 TAVR candidates were randomized, with 191 patients assigned to the CMR-guided group and 189 patients to the CT-guided group. In the modified intention-to-treat (mITT) cohort, comprising 267 patients who ultimately underwent TAVR (72.3% CMR-guided and 68.3% CT-guided), implantation success was achieved in 93.5% of CMR-guided patients and 90.7% of CT-guided patients. This resulted in a between-group difference of 2.8% with a 90% confidence interval [CI] of -2.7 to 8.2% and p<0.01 for non-inferiority. In the per-protocol (PP) cohort, which involved 248 patients (121 CMR-guided and 127 CT-guided), the between-group difference was 2.0% (90% CI: -3.8 to 7.8%, p<0.01 for non-inferiority).
In conclusion, this study provides compelling evidence that CMR-guided TAVR is non-inferior to CT-guided TAVR regarding device implantation success. Therefore, CMR can be considered a viable alternative for TAVR planning, particularly for patients with CKD, thus offering a safer and more practical approach to this critical cardiovascular procedure. This research significantly expands available options for clinicians and patients in transcatheter aortic valve replacement.
Link to the article: https://www.ahajournals.org/doi/10.1161/CIRCULATIONAHA.123.066498
References Reindl, M., Lechner, I., Holzknecht, M., Tiller, C., Fink, P., Oberhollenzer, F., Von Der Emde, S., Pamminger, M., Troger, F., Kremser, C., Laßnig, E., Danninger, K., Binder, R. K., Ulmer, H., Brenner, C., Klug, G., Bauer, A., Metzler, B., Mayr, A., & Reinstadler, S. J. (2023). Cardiac magnetic resonance imaging versus computed tomography to guide transcatheter aortic valve replacement (Tavr-cmr): A randomized, open-label, non-inferiority trial. Circulation, CIRCULATIONAHA.123.066498. https://doi.org/10.1161/CIRCULATIONAHA.123.066498
