Cardiac Magnetic Resonance Imaging Versus Computed Tomography to Guide Transcatheter Aortic Valve Replacement: A Randomized, Open-Label, Noninferiority Trial

BACKGROUND

Computed tomography (CT) is recommended for guiding transcatheter aortic valve replacement (TAVR). However, a sizable proportion of TAVR candidates have chronic kidney disease, in whom the use of iodinated contrast media is a limitation. Cardiac magnetic resonance imaging (CMR) is a promising alternative, but randomized data comparing the effectiveness of CMR-guided versus CT-guided TAVR are lacking.

METHODS

An investigator-initiated, prospective, randomized, open-label, noninferiority trial was conducted at 2 Austrian heart centers. Patients evaluated for TAVR according to the inclusion criteria (severe symptomatic aortic stenosis) and exclusion criteria (contraindication to CMR, CT, or TAVR, a life expectancy <1 year, or chronic kidney disease level 4 or 5) were randomized (1:1) to undergo CMR or CT guiding. The primary outcome was defined according to the Valve Academic Research Consortium-2 definition of implantation success at discharge, including absence of procedural mortality, correct positioning of a single prosthetic valve, and proper prosthetic valve performance. Noninferiority was assessed using a hybrid modified intention-to-treat/per-protocol approach on the basis of an absolute risk difference margin of 9%.

RESULTS

Between September 11, 2017, and December 16, 2022, 380 candidates for TAVR were randomized to CMR-guided (191 patients) or CT-guided (189 patients) TAVR planning. Of these, 138 patients (72.3%) in the CMR-guided group and 129 patients (68.3%) in the CT-guided group eventually underwent TAVR (modified intention-to-treat cohort). Of these 267, 19 patients had protocol deviations, resulting in a per-protocol cohort of 248 patients (121 CMR-guided, 127 CT-guided). In the modified intention-to-treat cohort, implantation success was achieved in 129 patients (93.5%) in the CMR group and in 117 patients (90.7%) in the CT group (between-group difference, 2.8% [90% CI, -2.7% to 8.2%]; P<0.01 for noninferiority). In the per-protocol cohort (n=248), the between-group difference was 2.0% (90% CI, -3.8% to 7.8%; P<0.01 for noninferiority).

CONCLUSIONS

CMR-guided TAVR was noninferior to CT-guided TAVR in terms of device implantation success. CMR can therefore be considered as an alternative for TAVR planning.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT03831087.

Improved in-hospital outcome for radial access in a large contemporary cohort of primary percutaneous coronary intervention

Background

Randomised controlled trials have shown diverse results for radial access in patients undergoing primary percutaneous coronary intervention (PPCI). Moreover, it is questionable whether radial access improves outcome in patients with cardiogenic shock undergoing PPCI. We aimed to investigate the outcome according to access site in patients with or without cardiogenic shock, in daily clinical practice.

Methods

For the present analysis we included 9,980 patients undergoing PPCI between 2012 and 2018, registered in the multi-centre, nationwide registry on PCI for myocardial infarction (MI). In-hospital mortality, major adverse cardiovascular events (MACE), and net adverse clinical events (NACE) until discharge were compared between 4,498 patients with radial (45%) and 5,482 patients with femoral (55%) access.

Results

Radial compared to femoral access was associated with lower in-hospital mortality (3.5% vs. 7.7%; P<0.01). Multivariable logistic regression analysis confirmed reduced in-hospital mortality [odds ratio (OR) 0.57, 95% confidence interval (CI): 0.43 to 0.75]. Furthermore, MACE (OR 0.60, 95% CI: 0.47 to 0.78) as well as NACE (OR 0.59, 95% CI: 0.46 to 0.75) occurred less frequently in patients with radial access. Interaction analysis with cardiogenic shock showed an effect modification, resulting in lower mortality in PCI via radial access in patients without, but no difference in those with cardiogenic shock (OR 1.78, 95% CI: 1.07 to 2.96).

Conclusions

Radial access for patients with acute MI undergoing PPCI is associated with improved survival in a large contemporary cohort of daily practice. However, this beneficial effect is restricted to hemodynamically stable patients.

Effect of the COVID-19 Pandemic on Treatment Delays in Patients with ST-Segment Elevation Myocardial Infarction

Coronavirus disease 19 (COVID-19) and its associated restrictions could affect ischemic times in patients with ST-segment elevation myocardial infarction (STEMI). The objective of this study was to investigate the influence of the COVID-19 outbreak on ischemic times in consecutive all-comer STEMI patients. We included consecutive STEMI patients (n = 163, median age: 61 years, 27% women) who were referred to seven tertiary care hospitals across Austria for primary percutaneous coronary intervention between 24 February 2020 (calendar week 9) and 5 April 2020 (calendar week 14). The number of patients, total ischemic times and door-to-balloon times in temporal relation to COVID-19-related restrictions and infection rates were analyzed. While rates of STEMI admissions decreased (calendar week 9/10 (n = 69, 42%); calendar week 11/12 (n = 51, 31%); calendar week 13/14 (n = 43, 26%)), total ischemic times increased from 164 (interquartile range (IQR): 107-281) min (calendar week 9/10) to 237 (IQR: 141-560) min (calendar week 11/12) and to 275 (IQR: 170-590) min (calendar week 13/14) (p = 0.006). Door-to-balloon times were constant (p = 0.60). There was a significant difference in post-interventional Thrombolysis in myocardial infarction (TIMI) flow grade 3 in patients treated during calendar week 9/10 (97%), 11/12 (84%) and 13/14 (81%; p = 0.02). Rates of in-hospital death and re-infarction were similar between groups (p = 0.48). Results were comparable when dichotomizing data on 10 March and 16 March 2020, when official restrictions were executed. In this cohort of all-comer STEMI patients, we observed a 1.7-fold increase in ischemic time during the outbreak of COVID-19 in Austria. Patient-related factors likely explain most of this increase. Counteractive steps are needed to prevent further cardiac collateral damage during the ongoing COVID-19 pandemic.