Hearts, Volume 6, Issue 4 (December 2025) – 4 articles

Background: Randomized controlled trials (RCTs) are the foundation of evidence-based medicine. However, the rapid pace of technological innovation in cardiovascular surgery and interventional cardiology challenges the traditional RCT framework. Observational studies may hold renewed value in fields where device evolution outpaces the time required to validate clinical outcomes. Methods: This analysis evaluates 270 randomized and non-randomized studies in transcatheter aortic valve implantation (TAVI), one of the most rapidly evolving areas in cardiovascular medicine. The investigation follows two lines: first, mapping the timeline of major RCTs against the introduction of new prosthetic models; second, comparing the prevalence, duration, and role of randomized (R) versus non-randomized (NR) studies. Results: The timeline reveals a persistent misalignment between innovation and validation. New prosthetic models frequently enter the market while RCTs for prior generations are still ongoing. For example, the Sapien 3 valve was approved, while trials on Sapien XT were still enrolling. Similarly, newer Evolut and Acurate models were introduced during ongoing studies of earlier versions, often prompting new studies before existing ones concluded. This leapfrogging effect fragments the evidence base and delays definitive comparisons. In parallel, randomized trials have increased in number and tend to be shorter in duration, reflecting a maturing field. However, non-randomized studies remain crucial for early testing and post-market surveillance. Conclusions: In a field with rapid technological evolution a sort of Zeno’s paradox occurs: long-term validation cannot keep pace with fast innovation, resetting the evidence base with each new model. To overcome this paradox, a paradigm shift in evidence generation is desirable. Future strategies must augment adaptive trial designs, leverage real-world data and use higher-level, advanced analyses to incorporate subjective variables and phenotypic diversity, to reduce confounding factors and speed up data access. Higher-level, integrative evidence analytics could help Achilles walk alongside the tortoise. Full article

Background: Myocardial scar and fibrosis predict adverse cardiac outcomes. Late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) is the reference standard for detection. However, it requires gadolinium-based contrast agents (GBCAs), which may be unsuitable for some patients. Cine balanced steady-state free precession (bSSFP) sequences are universally acquired in routine CMR. They may enable contrast-free scar detection via radiomics analysis. Aim: To systematically review the diagnostic accuracy of cine CMR radiomics for myocardial scar or fibrosis detection. The reference standard is visual or threshold-based LGE. Methods: This review followed PRISMA guidelines and was registered in PROSPERO (CRD420251121699). We searched MEDLINE, Embase, and Cochrane Library up to 8 August 2025. Eligible studies compared cine CMR radiomics with LGE-based assessment in patients with suspected or known scar/fibrosis. Quality was assessed using QUADAS-2 and Radiomics Quality Score (RQS). Results: Five retrospective studies (n = 1484) were included. Two focused on myocardial infarction, two on hypertrophic cardiomyopathy, and one on ischaemic versus dilated cardiomyopathy. Diagnostic performance was good to excellent (AUC 0.74–0.96). Methodological heterogeneity was substantial in reference standards, segmentation, preprocessing, feature selection, and modelling. Only one study used external validation. QUADAS-2 showed high bias risk in patient selection and index test domains. RQS scores were low (30–42%), indicating limited reproducibility and validation. Conclusions: Cine CMR radiomics shows promise as a non-contrast alternative for detecting myocardial scar and fibrosis. However, methodological standardisation, multicentre validation, and prospective studies are needed before clinical adoption. Full article

Background: Heart failure (HF) is common and deadly, affecting over 60 million people worldwide, and it remains a leading cause of hospitalization and post-discharge death. One-year mortality after an acute decompensated HF (ADHF) admission often approaches 40%. Prognostic models are critical for stratifying mortality risk in heart failure (HF) patients. This study compared the performance of the MAGGIC and BCN Bio-HF models in predicting 1-year and 3-year all-cause mortality (ACM) in patients discharged after acute decompensated HF (ADHF). Methods: A retrospective analysis was conducted on 229 patients hospitalized for ADHF at the Clinical University Hospital of Zaragoza. The required variables were extracted from medical records, and ACM risks were calculated using web-based tools. Calibration, discrimination (AUC), and Kaplan–Meier survival analysis and calibration curves assessed risk stratification and alignment with observed outcomes. Reclassification metrics (Net Reclassification Index [NRI], Integrated Discrimination Improvement [IDI]) were used to compare the models’ predictive performances. Results: Both of the models demonstrated robust discrimination for 1-year ACM (AUC: MAGGIC = 0.738, BCN Bio-HF = 0.769) but showed lower performance for 3-year predictions. Calibration was poor, with both models exhibiting significant risk underestimation at the individual level. MAGGIC achieved higher sensitivity (1-year: 0.911; 3-year: 0.685), favoring high-risk patient identification, whereas BCN Bio-HF offered superior specificity (1-year: 0.679; 3-year: 0.746) and a positive prediction value, reducing false positives. BCN Bio-HF showed a significant 12.7% reclassification improvement for 1-year mortality prediction. Conclusions: BCN Bio-HF did not outperform MAGGIC in our cohort. MAGGIC is preferable for the initial high-risk patient identification, requiring more intense short-term follow-up, while BCN Bio-HF’s higher specificity is best-suited to avoid overtreatment. Altogether, the clinical utility of both models was limited in our cohort by severe miscalibration, which may render adequate risk stratification difficult. Full article

Background: Balloon aortic valvuloplasty is a procedure for treating aortic stenosis, as well as being a preliminary step before transcatheter aortic valve implantation. Balloon aortic valvuloplasty requires inserting a balloon catheter into the aortic valve and repeatedly inflating it to widen the narrowed valve. With a wide range of equipment, operators rely on manufacturer data to guide the balloon use during surgery. However, such data can have variations of up to 10%, which can affect the procedures’ efficacy. Methods: In this paper, we report a bench-top proof-of-concept, automated, non-contact optical system that combines a linear delta robot (ROMI) equipped with a bright-field microscopy system, image stitching, and passive autofocusing algorithms to measure the diameters of aortic valvuloplasty balloons inflated using clinically relevant pressures. The system also introduces a laser projection system, enabling the use of passive autofocus algorithms to allow measuring transparent balloons. We evaluate three balloon brands (TRUE Dilatation, Edwards, and Z-MED II) across commonly used sizes and compare the measured diameters with vendor specifications. The developed system allows us to systematically determine the balloons’ diameters with submillimeter-level accuracy. Results: The experimental data shows that the TRUE Dilatation balloon presented the smallest deviations from the manufacturers’ data, even though the 22 and 24 mm balloons exceeded the 1% tolerance by +2.26% (over-inflation) and −1.56% (under-inflation), respectively. The Edwards Lifesciences and Z-MED II balloons presented inflation diameter variations ranging from −5.97% to + 8.81%, which led to a deviation of the specified balloon diameter of 1.76 mm. The standard error value obtained within our measurements revealed that the balloon diameters were consistent despite multiple inflations and were also resilient to repeated inflations up to the rated burst pressure. Conclusions: These results demonstrate the potential of the system presented herein to be adapted for in situ, contactless pre-operative balloon assessment in clinical settings. Full article