Enver Tahir

Dr. Enver Tahir


Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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6 January 2022 in European Heart Journal
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EPElina Larissa Petersen
Elina Larissa Petersen
AGAlina Goßling
Alina Goßling
GAGerhard Adam
Gerhard Adam
MAMartin Aepfelbacher
Martin Aepfelbacher
Christian Alexander BehrendtChristian Alexander Behrendt
Christian Alexander Behrendt
SBStefan Blankenberg
Stefan Blankenberg
Long-term sequelae may occur after SARS-CoV-2 infection. We comprehensively assessed organ-specific functions in individuals after mild to moderate SARS-CoV-2 infection compared with controls from the general population. Four hundred and forty-three mainly non-hospitalized individuals were examined in median 9.6 months after the first positive SARS-CoV-2 test and matched for age, sex, and education with 1328 controls from a population-based German cohort. We assessed pulmonary, cardiac, vascular, renal, and neurological status, as well as patient-related outcomes. Bodyplethysmography documented mildly lower total lung volume (regression coefficient −3.24, adjusted P = 0.014) and higher specific airway resistance (regression coefficient 8.11, adjusted P = 0.001) after SARS-CoV-2 infection. Cardiac assessment revealed slightly lower measures of left (regression coefficient for left ventricular ejection fraction on transthoracic echocardiography −0.93, adjusted P = 0.015) and right ventricular function and higher concentrations of cardiac biomarkers (factor 1.14 for high-sensitivity troponin, 1.41 for N-terminal pro-B-type natriuretic peptide, adjusted P ≤ 0.01) in post-SARS-CoV-2 patients compared with matched controls, but no significant differences in cardiac magnetic resonance imaging findings. Sonographically non-compressible femoral veins, suggesting deep vein thrombosis, were substantially more frequent after SARS-CoV-2 infection (odds ratio 2.68, adjusted P < 0.001). Glomerular filtration rate (regression coefficient −2.35, adjusted P = 0.019) was lower in post-SARS-CoV-2 cases. Relative brain volume, prevalence of cerebral microbleeds, and infarct residuals were similar, while the mean cortical thickness was higher in post-SARS-CoV-2 cases. Cognitive function was not impaired. Similarly, patient-related outcomes did not differ. Subjects who apparently recovered from mild to moderate SARS-CoV-2 infection show signs of subclinical multi-organ affection related to pulmonary, cardiac, thrombotic, and renal function without signs of structural brain damage, neurocognitive, or quality-of-life impairment. Respective screening may guide further patient management. The key question is: How does a mild to moderate course of SARS-CoV-2 infection in mainly non-hospitalized individuals impact intermediate-term organ-specific functions in comparison to the general population? The key findings are (i) a mild to moderate course of SARS-CoV-2 infection is associated with subsequent signs of subclinical multi-organ affection; (ii) associations mainly affect the pulmonary, cardiac, coagulation, and renal system; and (iii) no systematic associations with structural brain damage, neurocognition, or quality of life were observed. The take-home message is systematic screening of multi-organ function even after mild to moderate SARS-CoV-2 infection is recommended to identify individuals at risk and initiate appropriate preventive therapies.

18 September 2021 in European Radiology
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ETEnver Tahir
Enver Tahir
MAManuella Azar
Manuella Azar
SSSahar Shihada
Sahar Shihada
KSKatharina Seiffert
Katharina Seiffert
YGYvonne Goy
Yvonne Goy
GLGunnar K. Lund
Gunnar K. Lund
Objectives: Cancer therapy-related cardiac dysfunction (CTRCD) is a relevant clinical problem and needs early prediction. This study aimed to analyze myocardial injury using serial laboratory and cardiac magnetic resonance imaging (CMR) parameters after epirubicin-based chemotherapy compared with left-sided radiotherapy and to study their value for early prediction of CTRCD. Methods: Sixty-six consecutive women (53 ± 13 years) including n = 39 with epirubicin-based chemotherapy and n = 27 with left-sided radiotherapy were prospectively studied by 3 T CMR including left ventricular (LV) mass and volumes for ejection fraction (LVEF), as well as feature-tracking with global longitudinal strain (GLS) and T1/T2 mapping. CMR was performed at baseline, at therapy completion (follow-up 1, FU1), and after 13 ± 2 months (FU2). CTRCD was defined as LVEF decline of at least 10% to < 55% or a > 15% GLS change at FU2. Results: T1 and T2 increased at FU1 after epirubicin-based chemotherapy, but not after left-sided radiotherapy. CTRCD occurred in 20% of patients after epirubicin-based chemotherapy and in 4% after left-sided radiotherapy. T1 at FU1 was the best single parameter to predict CTRCD with an area under the curve (AUC) of 0.712 (CI 0.587–0.816, p = 0.005) with excellent sensitivity (100%, 66–100%), but low specificity (44%, 31–58%). Combined use of increased T1 and LVEF ≤ 60% at FU1 improved AUC to 0.810 (0.695–0.896) resulting in good sensitivity (78%, 44–95%) and specificity (84%, 72–92%). Conclusion: Only epirubicin-based chemotherapy, but not left-sided radiotherapy, resulted in increased T1/T2 myocardial relaxation times as a marker of myocardial injury. Combined use of CMR parameters may allow an early prediction of subsequent CTCRD. Key Points: • Myocardial T1 and T2 relaxation times increased at FU1 after epirubicin-based chemotherapy, but not after left-sided radiotherapy. • Cancer therapy–related cardiac dysfunction (CTRCD) occurred in 20% of patients after epirubicin-based chemotherapy and in 4% after left-sided radiotherapy. • Combined use of increased T1 and reduced LVEF had an AUC of 0.810 (0.695–0.896) to predict CTRCD with good sensitivity (78%, 44–95%) and specificity (84%, 72–92%).

26 June 2019 in European Journal of Preventive Cardiology
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ETEnver Tahir
Enver Tahir
BSBenedikt Scherz
Benedikt Scherz
JSJitka Starekova
Jitka Starekova
KMKai Muellerleile
Kai Muellerleile
RFRoland Fischer
Roland Fischer
GLGunnar K Lund
Gunnar K Lund
Aims: The aim of this study was to investigate the occurrence of myocardial injury and cardiac dysfunction after an endurance race by biomarkers and cardiac magnetic resonance in triathletes with and without myocardial fibrosis. Methods and results: Thirty asymptomatic male triathletes (45 ± 10 years) with over 10 training hours per week and 55 ± 8 ml/kg per minute maximal oxygen uptake during exercise testing were studied before (baseline) and 2.4 ± 1.1 hours post-race. Baseline cardiac magnetic resonance included cine, T1/T2, late gadolinium enhancement (LGE) and extracellular volume imaging. Post-race non-contrast cardiac magnetic resonance included cine and T1/T2 mapping. Non-ischaemic myocardial fibrosis was present in 10 triathletes (LGE+) whereas 20 had no fibrosis (LGE–). At baseline, LGE + triathletes had higher peak exercise systolic blood pressure with 222 ± 21 mmHg compared to LGE– triathletes (192 ± 30 mmHg, P < 0.01). Post-race troponin T and creatine kinase MB were similarly increased in both groups, but there was no change in T2 and T1 from baseline to post-race with 54 ± 3 ms versus 53 ± 3 ms ( P = 0.797) and 989 ± 21 ms versus 989 ± 28 ms ( P = 0.926), respectively. However, post-race left atrial ejection fraction was significantly lower in LGE + triathletes compared to LGE– triathletes (53 ± 6% vs. 59 ± 6%, P < 0.05). Furthermore, baseline atrial peak filling rates were lower in LGE – triathletes (121 ± 30 ml/s/m2) compared to LGE + triathletes (161 ± 34 ml/s/m2, P < 0.01). Post-race atrial peak filling rates increased in LGE– triathletes to 163 ± 46 ml/s/m2, P < 0.001), but not in LGE + triathletes (169 ± 50ml/s/m2, P = 0.747). Conclusion: Despite post-race troponin T release, we did not find detectable myocardial oedema by cardiac magnetic resonance. However, the unfavourable blood pressure response during exercise testing seemed to be associated with post-race cardiac dysfunction, which could explain the occurrence of myocardial fibrosis in triathletes.

31 December 2022 in Scientific Reports
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JEJennifer Erley
Jennifer Erley
JSJitka Starekova
Jitka Starekova
MSMartin Sinn
Martin Sinn
KMKai Muellerleile
Kai Muellerleile
HCHang Chen
Hang Chen
ETEnver Tahir
Enver Tahir
Strain is an important imaging parameter to determine myocardial deformation. This study sought to 1) assess changes in left ventricular strain and ejection fraction (LVEF) from acute to chronic ST-elevation myocardial infarction (STEMI) and 2) analyze strain as a predictor of late gadolinium enhancement (LGE). 32 patients with STEMI and 18 controls prospectively underwent cardiac magnetic resonance imaging. Patients were scanned 8 $$\pm$$ ± 5 days and six months after infarction (± 1.4 months). Feature tracking was performed and LVEF was calculated. LGE was determined visually and quantitatively on short-axis images and myocardial segments were grouped according to the LGE pattern (negative, non-transmural and transmural). Global strain was impaired in patients compared to controls, but improved within six months after STEMI (longitudinal strain from −14 ± 4 to −16 ± 4%, p < 0.001; radial strain from 38 ± 11 to 42 ± 13%, p = 0.006; circumferential strain from −15 ± 4 to −16 ± 4%, p = 0.023). Patients with microvascular obstruction showed especially attenuated strain results. Regional strain persisted impaired in LGE-positive segments. Circumferential strain could best distinguish between LGE-negative and -positive segments (AUC 0.73- 0.77). Strain improves within six months after STEMI, but remains impaired in LGE-positive segments. Strain may serve as an imaging biomarker to analyze myocardial viability. Especially circumferential strain could predict LGE.

1 February 2018 in Journal of Cardiovascular Magnetic Resonance
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SBSebastian Bohnen
Sebastian Bohnen
MAMaxim Avanesov
Maxim Avanesov
AJAnnika Jagodzinski
Annika Jagodzinski
RSRenate B. Schnabel
Renate B. Schnabel
TZTanja Zeller
Tanja Zeller
KMKai Muellerleile
Kai Muellerleile
The purpose of this work is to describe the objectives and design of cardiovascular magnetic resonance (CMR) imaging in the single center, prospective, population-based Hamburg City Health study (HCHS). The HCHS aims at improving risk stratification for coronary artery disease (CAD), atrial fibrillation (AF) and heart failure (HF). The HCHS will finally include 45,000 inhabitants of the city of Hamburg (Germany) between 45 and 74 years who undergo an extensive cardiovascular evaluation and collection of biomaterials. Risk-scores for CAD, AF and HF are used to create enriched subpopulations who are invited for CMR. A total number of approximately 12,362 subjects will undergo CMR and incident CAD, AF and HF will be assessed after 6 years follow-up. The standard CMR protocol includes cine-CMR, T1 and T2 mapping, aortic/mitral valve flow measurements, Late gadolinium enhancement, angiographies and measurements of aortic distensibility. A stress-perfusion scan is added in individuals at risk for CAD. The workflow of CMR data acquisition and analyses was evaluated in a pilot cohort of 200 unselected subjects. The obtained CMR findings in the pilot cohort agree with current reference values and demonstrate the ability of the established workflow to accomplish the objectives of HCHS. CMR in HCHS promises novel insights into major cardiovascular diseases, their subclinical precursors and the prognostic value of novel imaging biomarkers. The HCHS database will facilitate combined analyses of imaging, clinical and molecular data (“Radiomics”).

23 December 2020 in European Radiology
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HLHy Van Lam
Hy Van Lam
MGMichael Groth
Michael Groth
TMThomas Mir
Thomas Mir
PBPeter Bannas
Peter Bannas
GLGunnar K. Lund
Gunnar K. Lund
ETEnver Tahir
Enver Tahir
Objectives: To evaluate systolic cardiac dysfunction in paediatric MFS patients with chest wall deformity using cardiac magnetic resonance (CMR) imaging and feature-tracking strain analysis. Methods: Forty paediatric MFS patients (16 ± 3 years, range 8−22 years) and 20 age-matched healthy controls (16 ± 4 years, range 11−24 years) were evaluated retrospectively. Biventricular function and volumes were determined using cine sequences. Feature-tracking CMR was used to assess global systolic longitudinal (GLS), circumferential (GCS) and radial strain (GRS). A dedicated balanced turbo field echo sequence was used to quantify chest wall deformity by measuring the Haller index (HI). Results: LV volumes and ejection fraction (EF) were similar in MFS patients and controls. There was a trend for lower right ventricular (RV) volume (75 ± 17 vs. 81 ± 10 ml/m2, p = 0.08), RV stroke volume (41 ± 12 vs. 50 ± 5 ml/m2, p < 0.001) and RVEF (55 ± 10 vs. 62 ± 6%, p < 0.01) in MFS patients. A subgroup of MFS patients had an increased HI compared to controls (4.6 ± 1.7 vs. 2.6 ± 0.3, p < 0.001). They demonstrated a reduced RVEF compared to MFS patients without chest wall deformity (50 ± 11% vs. 58 ± 8%, p = 0.01) and controls (p < 0.001). LV GLS was attenuated when HI ≥ 3.25 (- 16 ± 2 vs. - 18 ± 3%, p = 0.03), but not GCS and GRS. LV GLS (p < 0.01) and GCS (p < 0.0001) were attenuated in MFS patients compared to controls, but not GRS (p = 0.31). RV GLS was attenuated in MFS patients compared to controls (- 21 ± 3 vs. - 23 ± 3%, p < 0.05). Conclusion: Chest wall deformity in paediatric MFS patients is associated with reduced RV volume, ejection fraction and GLS. Feature-tracking CMR also indicates impairment of systolic LV function in paediatric MFS patients. Key Points: • Paediatric Marfan patients demonstrate reduced RV volume and ejection fraction compared to healthy controls. • A concordant attenuation in RV global longitudinal strain was observed in Marfan patients, while the RV global circumferential strain was increased, indicating a possible compensatory mechanism. • Subgroup analyses demonstrated alterations in RV ejection fraction and RV/LV global strain parameters, indicating a possible association of severe chest wall deformity with biventricular dysfunction in paediatric Marfan patients.