LAUSR

To the Editor, Transradial primary percutaneous coronary intervention (TR-PCI) in ST-elevation myocardial infarction (STEMI) has been shown to reduce mortality, major adverse cardiac events, and bleeding compared with transfemoral PCI (TF-PCI) in multiple randomized studies. Based on these data, the American Heart Association recommended a “radialfirst” strategy for PCI in STEMI patients among experienced operators. However, patients with STEMI are susceptible to electrical instability and cardiac arrest (CA) in whom it is unclear whether a “radial-first” approach is applicable. Therefore, we studied the feasibility and role of TR-PCI among these patients. We queried a registry of STEMI patients treated with PCI at our center between January 1, 2011, and December 31, 2018. Baseline and procedural characteristics, in-hospital management, and outcomes including major bleeding within 72 h were collected prospectively and adjudicated by the standards of the American College of Cardiology National Cardiovascular Data Registry (ACC NCDR) CathPCI Registry. We identified patients that had CA defined as pulseless clinical scenarios that were pulseless electrical activity, bradycardic, or tachycardic arrests requiring cardiopulmonary resuscitation and/or emergency defibrillation within 24 h prior to PCI. No patients were excluded. During the study period (July 15, 2014), we implemented TR-PCI as the standard approach in STEMI patients at our center when feasible. We assessed for temporal changes in the use of TR-PCI, technical success rates among those who underwent TR-PCI, and compared procedural outcomes with those undergoing TF-PCI in an intention-to-treat manner. To assess for predictors of major bleeding, all variables were assessed in univariable logistic regression and those with p < 0.10 were included in multivariable analysis with final model selection using stepwise regression. This study was approved by the Institutional Review Board at our institution and waiver of written informed consent was provided. A total of 216 patients with STEMI and CA treated with PCI were included. Utilization of TR-PCI significantly increased from 2.9% in 2011 to 87.1% in 2018 (p < 0.001, Figure 1). TR-PCI was attempted in 91 patients and was successful in 80 patients (87.9%); vascular access failure occurred in eight cases and technical failure after successful radial access occurred in three cases. Those who underwent attempted TR-PCI had a greater body mass index (29.7 [25.6, 33.4] vs. 27.5 [24.0, 31.6] kg/m, p = 0.037) and were less likely to have a history of coronary artery bypass grafting (1.1% vs. 8.8%, p = 0.034) with otherwise similar baseline characteristics in comparison with TF-PCI patients. Door-to-balloon time (90 [68, 116] vs. 105 [76, 141] min, p = 0.025) and contrast volume (150 [100, 179] vs. 153 [120, 225] ml, p = 0.031) were significantly lower in TR-PCI patients with no differences in fluoroscopy dose (1396 [901, 2073] vs. 1246 mGy [722, 2041], p = 0.329), antiplatelet or anticoagulant strategies, mechanical circulatory support use (30.8% vs. 41.6%, p = 0.138), or in-hospital mortality (13.2% vs. 19.2%, p = 0.324). There was significant reduction in overall femoral access amongst those with attempted TR-PCI (None: 59.3%, single: 33.0%, bilateral: 7.7%; p < 0.001) than with TF-PCI (None: 2.4%, single: 72.8%, bilateral: 24.8%). In multivariable analysis adjusting for age, gender, peripheral arterial disease, diabetes, fluoroscopy time, mechanical circulatory support use, and total femoral access, TR-PCI was an independent predictor for less major bleeding (OR 0.34, 95% CI 0.11–0.93, p = 0.045). Our report has several implications. First, we found the use of TR-PCI to be feasible in patients with STEMI and CA and observed a 30-fold increase in usage of TR-PCI over the study period. We found that crossover to TF-PCI was low with no significant increase in D2BT or adverse consequences such as increased fluoroscopy or contrast doses among patients who received TR-PCI. Additionally, we demonstrated the efficacy of a system of care which advocated for a “radialfirst” strategy when clinically appropriate to successfully promote adoption of TR-PCI in this high-risk population. Secondly, use of TR-PCI in patients with STEMI and CA was an independent predictor for less major bleeding. This finding highlights the appropriate use of TR-PCI as a critical bleeding avoidance strategy in a population previously reported to be at highest risk. Although we noted a numerical reduction in the absolute risk of in-hospital mortality of 6%, the cohort was too small to detect a statistically significant difference. There are several limitations of this analysis. Principally, this is a single center study including STEMI patients with CA who survived to cardiac catheterization laboratory arrival and successfully underwent PCI. Use of TR-PCI was not randomized and as such analysis is subject to inherent limitations. Received: 25 October 2021 Accepted: 4 November 2021