Background: Cardiac troponin (cTn) T and cTnI are considered cardiac specific and equivalent in the diagnosis of acute myocardial infarction. Previous studies suggested rare skeletal myopathies as a noncardiac source of cTnT. We aimed to confirm the reliability/cardiac specificity of cTnT in patients with various skeletal muscle disorders (SMDs). Methods: We prospectively enrolled patients presenting with muscular complaints (≥2 weeks) for elective evaluation in 4 hospitals in 2 countries. After a cardiac workup, patients were adjudicated into 3 predefined cardiac disease categories. Concentrations of cTnT/I and resulting cTnT/I mismatches were assessed with high-sensitivity (hs-) cTnT (hs-cTnT–Elecsys) and 3 hs-cTnI assays (hs-cTnI–Architect, hs-cTnI–Access, hs-cTnI–Vista) and compared with those of control subjects without SMD presenting with adjudicated noncardiac chest pain to the emergency department (n=3508; mean age, 55 years; 37% female). In patients with available skeletal muscle biopsies, TNNT/I1-3 mRNA differential gene expression was compared with biopsies obtained in control subjects without SMD. Results: Among 211 patients (mean age, 57 years; 42% female), 108 (51%) were adjudicated to having no cardiac disease, 44 (21%) to having mild disease, and 59 (28%) to having severe cardiac disease. hs-cTnT/I concentrations significantly increased from patients with no to those with mild and severe cardiac disease for all assays (all P <0.001). hs-cTnT–Elecsys concentrations were significantly higher in patients with SMD versus control subjects (median, 16 ng/L [interquartile range (IQR), 7–32.5 ng/L] versus 5 ng/L [IQR, 3–9 ng/L]; P <0.001), whereas hs-cTnI concentrations were mostly similar (hs-cTnI–Architect, 2.5 ng/L [IQR, 1.2–6.2 ng/L] versus 2.9 ng/L [IQR, 1.8–5.0 ng/L]; hs-cTnI–Access, 3.3 ng/L [IQR, 2.4–6.1 ng/L] versus 2.7 ng/L [IQR, 1.6–5.0 ng/L]; and hs-cTnI–Vista, 7.4 ng/L [IQR, 5.2–13.4 ng/L] versus 7.5 ng/L [IQR, 6–10 ng/L]). hs-cTnT–Elecsys concentrations were above the upper limit of normal in 55% of patients with SMD versus 13% of control subjects ( P <0.01). mRNA analyses in skeletal muscle biopsies (n=33), mostly (n=24) from individuals with noninflammatory myopathy and myositis, showed 8-fold upregulation of TNNT2 , encoding cTnT (but none for TNNI3 , encoding cTnI) versus control subjects (n=16, P _Wald <0.001); the expression correlated with pathological disease activity ( R =0.59, P _t-statistic <0.001) and circulating hs-cTnT concentrations ( R =0.26, P _t-statistic =0.031). Conclusions: In patients with active chronic SMD, elevations in cTnT concentrations are common and not attributable to cardiac disease in the majority. This was not observed for cTnI and may be explained in part by re-expression of cTnT in skeletal muscle. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03660969.

Early and late microvascular obstruction (MVO) assessed by cardiovascular magnetic resonance (CMR) are prognostic markers for short-term clinical endpoints after acute ST-elevation myocardial infarction (STEMI). However, there is a lack of studies with long-term follow-up periods (>24 months).

Myocardial involvement in AAV patients might be silent, presenting with no or nonspecific symptoms, normal ECG, and preserved left-ventricular ejection fraction (LV-EF). Since up to 50% of deaths in these patients may be due to myocardial involvement, a reliable diagnostic tool is warranted. In contrast to LGE-CMR, which has its strengths in detecting focal inflammatory or fibrotic processes, recent mapping techniques are able to detect even subtle, diffuse inflammatory or fibrotic processes. Our study sought to investigate ANCA (antineutrophil cytoplasmic antibody) associated vasculitides (AAV) patients for myocardial involvement by a cardiovascular magnetic resonance (CMR) protocol, including late gadolinium enhancement (LGE) and mapping sequences. Thirty seven AAV patients were prospectively enrolled and underwent CMR imaging. Twenty healthy volunteers served as controls. Mean LV-EF was 64%; LGE prevalence of the AAV patients was 43%. AAV patients had higher median native T1 (988 vs. 952 ms, p < 0.001), lower post-contrast T1 (488 vs. 524 ms, p = 0.03), expanded extracellular volume (ECV) (27.5 vs. 24.5%, p < 0.001), and higher T2 (53 vs. 49 ms, p < 0.001) compared to controls, with most parameters independent of the LGE status. Native T1 and T2 in AAV patients showed the highest prevalence of abnormally increased values beyond the 95% percentile of controls. AAV patients demonstrated increased T1, ECV, and T2 values, with native T1 and T2 showing the highest prevalence of values beyond the 95% percentile of normal. Since these findings seem to be independent of LGE, mapping techniques may provide complementary information to LGE-CMR in the assessment of myocardial involvement in patients with AAV.

Aim: We aimed to investigate the comparative prognostic value of left ventricular ejection fraction (LVEF), mitral annular plane systolic excursion (MAPSE), fast manual long-axis strain (LAS) and global longitudinal strain (GLS) determined by cardiac magnetic resonance (CMR) in patients after ST-segment elevation myocardial infarction (STEMI). Methods and results: This observational cohort study included 445 acute STEMI patients treated with primary percutaneous coronary intervention (pPCI). Comprehensive CMR examinations were performed 3 [interquartile range (IQR): 2–4] days after pPCI for the determination of left ventricular (LV) functional parameters and infarct characteristics. Primary endpoint was the occurrence of major adverse cardiac events (MACE) defined as composite of death, re-infarction and congestive heart failure. During a follow-up of 16 [IQR: 12–49] months, 48 (11%) patients experienced a MACE. LVEF (p = 0.023), MAPSE (p < 0.001), LAS (p < 0.001) and GLS (p < 0.001) were significantly related to MACE. According to receiver operating characteristic analyses, only the area under the curve (AUC) of GLS was significantly higher compared to LVEF (0.69, 95% confidence interval (CI) 0.64–0.73; p < 0.001 vs. 0.60, 95% CI 0.55–0.65; p = 0.031. AUC difference: 0.09, p = 0.020). After multivariable analysis, GLS emerged as independent predictor of MACE even after adjustment for LV function, infarct size and microvascular obstruction (hazard ratio (HR): 1.13, 95% CI 1.01–1.27; p = 0.030), as well as angiographical (HR: 1.13, 95% CI 1.01–1.28; p = 0.037) and clinical parameters (HR: 1.16, 95% CI 1.05–1.29; p = 0.003). Conclusion: GLS emerged as independent predictor of MACE after adjustment for parameters of LV function and myocardial damage as well as angiographical and clinical characteristics with superior prognostic validity compared to LVEF. Graphic

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.