Stress CMR in the fast lane: implications beyond image quality

This editorial refers to ‘Accelerated stress CMR for the detection of significant coronary artery disease: a prospective randomized diagnostic accuracy study’, by M. Elshibly et al., https://doi.org/10.1093/ehjci/jeaf322. Stress perfusion cardiovascular magnetic resonance (CMR) has matured into a first-line diagnostic and prognostic tool for patients with suspected and known chronic coronary syndromes. Its diagnostic accuracy, prognostic value, and cost-effectiveness are firmly established across randomized trials, registries, and health economic analyses.1 Beyond ischaemia, CMR also enables assessment of alternative causes of chest pain, including inflammation and cardiomyopathies. Despite this success, access to stress CMR remains insufficient due to capacity, workforce, and reimbursement constraints. Against this backdrop, any innovation that meaningfully shortens scan time without sacrificing diagnostic performance represents a concrete step towards improving CMR accessibility. Elshibly et al.2 present the first prospective, randomized, paired diagnostic accuracy study comparing an accelerated stress-only perfusion CMR protocol with a conventional stress-rest protocol, using invasive fractional flow reserve as the reference standard. The message is clear: a protocol shortened by ∼24 min maintains non-inferior vessel-level diagnostic accuracy while substantially improving patient tolerability. Several groups have previously demonstrated the feasibility of rapid or abbreviated CMR protocols. However, none relied on paired comparisons of two protocols with invasive physiology as a reference.3 What distinguishes the present work is its randomized, paired design, use of an invasive reference standard and formal non-inferiority framework. Acceleration was achieved through omission of rest perfusion, real-time free-breathing cine imaging, and single-shot late gadolinium enhancement (LGE). This evidence matters because acceleration in clinical imaging always requires weighing trade-offs not only in technical terms, but more importantly in terms of potential loss of clinically relevant information. By testing the entire accelerated package, this study provides a pragmatic and positive answer to a key question: Can we safely run a fast clinical stress-CMR list for the assessment of chronic chest pain without degrading diagnostic confidence? One of the most important aspects of this study is the prospective validation of a stress-perfusion-plus-LGE-only strategy. The omission of rest perfusion has long been debated. Traditionally, rest imaging has been justified for artefact adjudication, infarct detection, and perfusion reserve assessment. Prior retrospective analyses have suggested that rest perfusion adds little to diagnostic accuracy when high-quality LGE is available.4 Elshibly et al. now extend this concept into the prospective domain. Their findings add to the understanding that in routine ischaemia detection, rest perfusion is often redundant. This is particularly relevant for CMR, where LGE provides highly sensitive infarct detection. Prognostically, both infarct burden and hyperaemic myocardial blood flow have consistently been shown to drive outcome.5,6 The omission of rest perfusion is often viewed as an obstacle to fully quantitative ischaemia assessment. This study shows that such concepts may need to evolve for accelerated clinical workflows that prioritize diagnostic efficiency over comprehensive physiologic phenotyping.7 Caution is required when extrapolating these findings to broader patient populations. Prior infarction was present in only 16% of patients, and patients after PCI or coronary artery bypass surgery were not included. CMR has long been perceived as a ‘high-cost’ modality, largely driven by scanner capital costs rather than true per-examination economics. Once depreciation, service contracts, energy, and infrastructure are annualized across high-volume operation, the marginal equipment cost of CMR is already modest relative to the clinical information gained. When a comprehensive stress CMR examination can reliably be delivered in well under 20 min, the decisive economic effect is not a reduction in capital cost but a marked increase in utilization efficiency of the same resource. The resulting cost per diagnostic answer drops substantially, shifting CMR from being perceived as ‘high-cost’ to being competitively efficient among functional imaging strategies. The most underappreciated implication of accelerated CMR is structural scalability. Historically constrained by acquisition time, specialist staffing, and post-processing burden, CMR is now entering an era where rapid acquisition, automated reconstruction, AI-based segmentation, and automated reporting fundamentally change its operating model. If current trends continue, CMR is likely to play a central role not only in diagnostic cardiology, but also in preventive cardiovascular medicine. From an ischaemia-detection perspective, cine imaging contributes little incremental value beyond perfusion and LGE. Since left ventricular function is usually already assessed by echocardiography, dropping cine imaging completely could further reduce scan time. Conversely, it may be time to reconsider the sequential testing paradigm altogether: selective frontline CMR could potentially replace initial echocardiography in stable chest pain, providing function, ischaemia, and tissue characterization in a single examination. Such an approach could reduce coronary interventions, improve aetiologic diagnosis, and become economically preferable. The proliferation of highly specialized CMR protocols reflects technological opportunity rather than clinical necessity. From a systems perspective, the long-term goal should not be an ever-expanding menu of tailored protocols, but rather a limited number of flexible, multipurpose acquisitions that can be post-processed according to clinical need. Accelerated stress CMR, as tested here, represents an important step towards such modular workflows. The critical question for the field is not whether additional protocol variants are technically feasible, but whether a small number of robust, standardized acquisitions can cover most clinical use cases without loss of diagnostic information. The present study demonstrates that a clinically robust stress CMR examination can already be performed in