Maximilian Spieker

Myocardial T2 mapping reveals age- and sex-related differences in volunteers

BackgroundT2 mapping indicates to be a sensitive method for detection of tissue oedema hidden beyond the detection limits of T2-weighted Cardiovascular Magnetic Resonance (CMR). However, due to variability of baseline T2 values in volunteers, reference values need to be defined. Therefore, the aim of the study was to investigate the effects of age and sex on quantitative T2 mapping with a turbo gradient-spin-echo (GRASE) sequence at 1.5 T. For that reason, we studied sensitivity issues as well as technical and biological effects on GRASE-derived myocardial T2 maps. Furthermore, intra- and interobserver variability were calculated using data from a large volunteer group.MethodsGRASE-derived multiecho images were analysed using dedicated software. After sequence optimization, validation and sensitivity measurements were performed in muscle phantoms ex vivo and in vivo. The optimized parameters were used to analyse CMR images of 74 volunteers of mixed sex and a wide range of age with typical prevalence of hypertension and diabetes. Myocardial T2 values were analysed globally and according to the 17 segment model. Strain-encoded (SENC) imaging was additionally performed to investigate possible effects of myocardial strain on global or segmental T2 values.ResultsEx vivo studies in muscle phantoms showed, that GRASE-derived T2 values were comparable to those acquired by a standard multiecho spinecho sequence but faster by a factor of 6. Besides that, T2 values reflected tissue water content. The in vivo measurements in volunteers revealed intra- and interobserver correlations with R2=0.91 and R2=0.94 as well as a coefficients of variation of 2.4% and 2.2%, respectively. While global T2 time significantly decreased towards the heart basis, female volunteers had significant higher T2 time irrespective of myocardial region. We found no correlation of segmental T2 values with maximal systolic, diastolic strain or heart rate. Interestingly, volunteers´ age was significantly correlated to T2 time while that was not the case for other coincident cardiovascular risk factors.ConclusionGRASE-derived T2 maps are highly reproducible. However, female sex and aging with typical prevalence of hypertension and diabetes were accompanied by increased myocardial T2 values. Thus, sex and age must be considered as influence factors when using GRASE in a diagnostic manner.

Myocardial T2 Mapping Increases Noninvasive Diagnostic Accuracy for Biopsy-Proven Myocarditis

Detection of myocardial inflammation in patients with clinically suspected acute myocarditis (sAMC) is of prognostic importance but remains a challenge in routine clinical practice [(1)][1]. Compared with endomyocardial biopsy (EMB), the diagnostic gold standard, cardiovascular magnetic resonance (

High body mass index is a risk factor for difficult deep sedation in percutaneous mitral valve repair

Background The safety and efficacy of deep sedation (DS) in MitraClip® procedures have been shown previously. However, clinical experience demonstrates that in some patients DS is difficult to achieve. We hypothesize that some patient characteristics can predict difficult DS. Methods We prospectively analysed 69 patients undergoing MitraClip® procedures using DS. Application of DS was graded as simple (group 1) or difficult (group 2) depending on a cumulative score based on one point for each of the following criteria: decrease in oxygen saturation, retention of carbon dioxide, disruptive body movements, and the need for catecholamines. Patients with one point or less were classified as group 1, and patients with two or more points were classified as group 2. Results In 58 of 69 patients (84.1%), the performance of DS was simple, while in 11 patients (15.9%), DS was difficult to achieve. Patients with difficult DS were characterized by a higher body mass index (33.7 ± 6.0 kg/m2 vs. 26.1 ± 4.1; p = 0.001), younger age (67 ± 13 years vs. 75 ± 13 years; p = 0.044), and reduced left ventricular ejection fraction (36% ± 10 vs. 45% ± 14; p = 0.051) and presented more often with an obstructive sleep apnoea syndrome (6.9% vs. 45.5%; p = 0.003). In the multivariate analysis, body mass index was an independent predictor of difficult DS. Using a body mass index of 31 kg/m2 as a cut-off value, the sensitivity of predicting difficult DS was 73%, and the specificity was 88%. Using a body mass index of 35 kg/m2 as a cut-off value, the specificity increased to 97%, with a sensitivity of 36%. Conclusion In patients with a higher body mass index who undergo MitraClip® procedures, DS might be difficult to perform.

T2-Mapping CMR increases the diagnostic sensitivity for detection of myocardial inflammation in patients with possible myocarditis - a prospective endomyocardial biopsy-controlled study

Myocarditis has been reported in up to 20% of sudden cardiac death in young adults and is a frequent precursor of dilated cardiomyopathy. Unfortunately, the diagnostic tools for detection of myocarditis are still imperfect: Sensitivity of endomyocardial biopsy (EMB) is reduced largely due to the inherent sampling error. Cardiac magnetic resonance (CMR) offers the advantage of analysing the whole myocardium, but contrast-enhanced as well as T2weighted CMR exhibit inadequate sensitivity, especially during early stages of inflammation. Our hypothesis was that quantitative T2 relaxation mapping increases diagnostic sensitivity in CMR-based diagnosis of myocarditis. Methods We carried out a prospective observational study in patients with probable acute myocarditis characterized by clinical presentation, new global or regional wall abnormalities or arrhythmias or hsTNT-elevation. Of the 55 patients screened, two patients did not undergo CMR (1 pacemaker, 1 ECLS-support) and 16 patients refused EMB. The remaining 37 patients underwent EMB and CMR examination (1.5 T, Archieva, Philips) within 36h. Histological evaluation was performed by two independent pathologists (hematoxylin eosin staining, picrosirius red, IH CD68, CD45R0 and CD3) and by molecular analysis for viral replication/genome. CMR data were analysed blinded with respect to ventricular volumes and ejection fraction as well as T2, LGE and Strain Encoded (SENC)Imaging. A GRASE sequence (15 Echoes separated by 10ms, res: 2x2x10 mm2, 3 short axis slices) was used for localized T2 mapping. Age-matched volunteers (37) served as controls for ROC curve analysis in terms of quantitative T2-mapping. Results were compared by two-sided t-Test; p<0.05 was considered significant. Results

State of the Art in Cardiovascular T2 Mapping: on the Way to a Cardiac Biomarker?

Purpose of ReviewParametric mapping fosters the role of cardiovascular magnetic resonance in its unique capability to evaluate myocardial tissue without the use of contrast agents. While there is a large body of literature highlighting the role of T1 mapping, the role of T2 mapping is less clear. This review aims to address the latest evidences for added clinical value of T2 mapping.Recent FindingsT2 mapping shows superior diagnostic accuracy in myocarditis, transplant rejection, and cardiac involvement in lupus erythematosus. Moreover, T2 values predict major adverse cardiovascular events in myocarditis and enable therapy monitoring in lupus erythematosus as well as after heart transplantation. In ischemic cardiomyopathy, T2 mapping discriminates acute from chronic injury and provides additional information for patient risk stratification.SummaryT2 mapping provides a robust, quantifiable non-contrast-enhanced myocardial biomarker. However, there is no standardization in acquisition protocols, which formulates the future need for standardization ahead of multi-center trails.

Prognostic value of impaired hepato‐renal function assessed by the MELD‐XI score in patients undergoing percutaneous mitral valve repair

The objective of this study was to assess the prognostic value of the Model for End‐stage Liver Disease (MELD)‐XI score in patients undergoing PMVR with the MitraClip system.

Effect of Acute Kidney Injury After Percutaneous Mitral Valve Repair on Outcome

Limited data exist on the occurrence of acute kidney injury (AKI) associated with percutaneous mitral valve repair (PMVR). The objectives of the present study were (1) to assess the prevalence of AKI after MitraClip (Abbott Vascular, Santa Clara, California) implantation, (2) to analyze the predictive factors of AKI, and (3) to evaluate the prognostic value of AKI after PMVR with a view to optimizing the management of high-risk patients. A total of 206 patients (serum creatinine [SCr] 1.3 ± 0.6 mg/dl, estimated glomerular filtration rate 55 ± 24 ml/min) who underwent PMVR were included. AKI was defined as an increase in SCr by ≥0.3 mg/dl within 48 hours or an increase in SCr by ≥1.5 times baseline. AKI was assessed during the first 5 days after MitraClip implantation. The incidence of AKI after MitraClip was 18% and none of the patients required dialysis. Age, logistic EuroSCORE, baseline renal function, N-terminal pro-B-type natriuretic peptide levels, serum glycated hemoglobin A1c, serum C-reactive protein, diuretic usage, and elevated right atrial pressure were the risk factors of AKI. Incidence of AKI was associated with poor outcome. Short-term mortality was increased (30-day mortality rate AKI vs no AKI: 18% vs 1%; p <0.001). Likewise, Kaplan-Meier analysis and log-rank test confirmed reduced long-term survival of patients with AKI (1-year all-cause mortality of patients with AKI vs patients with no AKI: 34% vs 13 %; p <0.001). In conclusion, every fifth patient experienced AKI after MitraClip implantation, which was associated with increased short-term mortality and a more than threefold increase in the risk of death 1 year after PMVR.

Effect of Atrial Fibrillation and Mitral Valve Gradients on Response to Percutaneous Mitral Valve Repair With the MitraClip System

Both pre-existing atrial fibrillation (AF) and mitral valve pressure gradients (MVPG) created by MitraClip implantation have demonstrated predictive power for unfavorable outcomes. Therefore, we aimed to assess the impact of MVPG following MitraClip on outcomes in patients with and without AF. A total of 200 patients who underwent MitraClip implantation in our institution were enrolled. Echocardiography was obtained before and after the procedure. The primary endpoint of the study was all-cause mortality 1-year after MitraClip implantation. Secondary end points were clinical improvements in NYHA functional class and reduction in MR severity after MitraClip implantation. Two hundred patients (74 ± 10 years, left ventricular ejection fraction 41% ± 14%, logistic EuroSCORE I 21 ± 15) were enrolled into the final analysis. One hundred twelve patients (56%) had pre-existing AF. One-year all-cause mortality was 17% without any differences between patients with or without pre-existing AF. Comparing postprocedural MVPG of surviving and deceased patients, deceased patients with pre-existing AF exhibited significantly elevated postprocedural MVPG compared with surviving patients without AF (4.8 ± 2.1 mm Hg vs 3.6 ± 1.8 mm Hg; p = 0.010). ROC analysis and Kaplan-Meier survival curves identified significantly reduced survival in AF patients with postprocedural MVPG above 4.0 mm Hg (p = 0.011). After MitraClip, a MVPG above 4.0 mm Hg in patients with pre-existing AF was a significant outcome predictor in univariate and multivariate analysis. In conclusion, we identified a high-risk cohort characterized by postprocedural MVPG above 4.0 mm Hg and pre-existing AF predicting poor long-term outcome.