@phdthesis{Sahiti2022,
  author    = {Sahiti, Floran},
  title     = {Myocardial Work - Application and Clinical Characterization of a New Echocardiographic Tool},
  doi       = {10.25972/OPUS-28226},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-282261},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2022},
  abstract  = {1 Summary Left ventricular (LV) ejection fraction (EF) and global longitudinal strain (GLS) are the most commonly used measures of LV function. Yet, they are highly dependent on loading conditions since higher afterload yields lower systolic deformation and thereby a lower LVEF and GLS - despite presumably unchanged LV myocardial contractile strength. Invasive pressure-volume loop measurements represent the reference standard to assess LV function, also considering loading conditions. However, this procedure cannot be used in serial investigations or large sample populations due to its invasive nature. The novel concept of echocardiography-derived assessment of myocardial work (MyW) is based on LV pressure-strain loops, may be a valuable alternative to overcome these challenges, and may also be used with relative ease in large populations. As MyW also accounts for afterload, it is considered less load-dependent than LVEF and GLS. The current PhD work addresses the application and clinical characterization of MyW, an innovative echocardiographic tool. As the method is new, we focused on four main topics: (a) To establish reference values for MyW indices, i.e., Global Work Index (GWI), Global Constructive Work (GCW), Global Wasted Work (GWW), and Global Work Efficiency (GWE); we addressed a wide age range and evaluated the association of MyW indices with age, sex and other clinical and echocardiography parameters in apparently cardiovascular healthy individuals. (b) To investigate the impact of cardiovascular (CV) risk factors on MyW indices and characterize the severity of subclinical LV deterioration in the general population. (c) To assess the association of the LV geometry, i.e., LV mass and dimensions, with MyW indices. (d) To evaluate in-hospital dynamics of MyW indices in patients hospitalized for acute heart failure (AHF). For the PhD thesis, we could make use of two larger cohorts: The STAAB population-based cohort study prospectively recruited and phenotyped a representative sample (5,000 individuals) of the general population of the City of W{\"u}rzburg, aged 30-79 years and free from symptomatic heart failure at the time of inclusion. We focused on the first half of the study sample (n=2473 individuals), which fulfilled the anticipated strata regarding age and sex. The Acute Heart Failure (AHF) Registry is a prospective clinical registry recruiting and phenotyping consecutive patients admitted for decompensated AHF to the Department of Medicine I, University Hospital W{\"u}rzburg, and observing the natural course of the disease. The AHF Registry focuses on the pathophysiological understanding, particularly in relation to the early phase after cardiac decompensation, with the aim to improve diagnosis and better-tailored treatment of patients with AHF. For the current study, we concentrated on patients who provided pairs of echocardiograms acquired early after index hospital admission and prior to discharge. The main findings of the PhD thesis were: From the STAAB cohort study, we determined the feasibility of large-scale MyW derivation and the accuracy of the method. We established reference values for MyW indices based on 779 analyzable, apparently healthy participants (mean age 49 ± 10 years, 59\% women), who were in sinus rhythm, free from CV risk factors or CV disease, and had no significant LV valve disease. Apart from GWI, there were no associations of other MyW indices with sex. Further, we found a disparate association with age, where MyW showed stable values until the age of 45 years, with an upward shift occurring beyond the age of 45. A higher age decade was associated with higher GWW and lower GWE, respectively. MyW indices only correlated weakly with common echocardiographic parameters, suggesting that MyW may add incremental information to clinically established parameters. Further analyses from the STAAB cohort study contributed to a better understanding of the impact of CV risk factors on MyW indices and the association of LV geometry with LV performance. We demonstrated that CV risk factors impacted selectively on GCW and GWW. Hypertension appears to profoundly compromise the work of the myocardium, in particular, by increasing both GCW and GWW. The LV in hypertension seems to operate at a higher energy level yet lower efficiency. Other classical CV risk factors (Diabetes mellitus, Obesity, Dyslipidemia, Smoking) - independent of blood pressure - impacted consistently and adversely on GCW but did not affect GWW. Further, all CV risk factors affected GWE adversely. We observed that any deviation from a normal LV geometric profile was associated with alterations on MyW. Of note, MyW was sensitive to early changes in LV mass and dimensions. Individuals with normal LV geometry yet established arterial hypertension exhibited a MyW pattern that is typically found in LV hypertrophy. Therefore, such a pattern might serve as an early sign of myocardial damage in hypertensive heart disease and might aid in risk stratification and primary prevention. From the AHF Registry, we selected individuals with serial in-hospital echocardiograms and described in-hospital changes in myocardial performance during recompensation. In patients presenting with a reduced ejection fraction (HFrEF), decreasing N-terminal pro-natriuretic peptide (NT-proBNP) levels as a surrogate of successful recompensation were associated with an improvement in GCW and GWI and consecutively in GWE. In contrast, in patients presenting with a preserved ejection fraction (HFpEF), there was no significant change in GCW and GWI. However, unsuccessful recompensation, i.e., no change or an increase in NT-proBNP levels, was associated with an increase in GWW. This suggests a differential myocardial response to de- and recompensation depending on the HF phenotype. Further, GWW as a surrogate of inappropriate LV energy consumption was elevated in all patients with AHF (compared to reference values) and was not associated with conventional markers as LVEF or NT-proBNP. In an exploratory analysis, GWW predicted the risk of death or rehospitalization within six months after discharge. Hence, GWW might carry incremental information beyond conventional markers of HF severity.},
  language  = {en}
}
@article{SahitiMorbachCejkaetal.2022,
  author    = {Sahiti, Floran and Morbach, Caroline and Cejka, Vladimir and Tiffe, Theresa and Wagner, Martin and Eichner, Felizitas A. and Gelbrich, G{\"o}tz and Heuschmann, Peter U. and St{\"o}rk, Stefan},
  title     = {Impact of cardiovascular risk factors on myocardial work-insights from the STAAB cohort study},
  series = {Journal of Human Hypertension},
  volume    = {36},
  journal   = {Journal of Human Hypertension},
  number    = {3},
  issn      = {1476-5527},
  doi       = {10.1038/s41371-021-00509-4},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-271770},
  pages     = {235-245},
  year      = {2022},
  abstract  = {Myocardial work is a new echocardiography-based diagnostic tool, which allows to quantify left ventricular performance based on pressure-strain loops, and has been validated against invasively derived pressure-volume measurements. Myocardial work is described by its components (global constructive work [GCW], global wasted work [GWW]) and indices (global work index [GWI], global work efficiency [GWE]). Applying this innovative concept, we characterized the prevalence and severity of subclinical left ventricular compromise in the general population and estimated its association with cardiovascular (CV) risk factors. Within the Characteristics and Course of Heart Failure STAges A/B and Determinants of Progression (STAAB) cohort study we comprehensively phenotyped a representative sample of the population of W{\"u}rzburg, Germany, aged 30-79 years. Indices of myocardial work were determined in 1929 individuals (49.3\% female, mean age 54 ± 12 years). In multivariable analysis, hypertension was associated with a mild increase in GCW, but a profound increase in GWW, resulting in higher GWI and lower GWE. All other CV risk factors were associated with lower GCW and GWI, but not with GWW. The association of hypertension and obesity with GWI was stronger in women. We conclude that traditional CV risk factors impact selectively and gender-specifically on left ventricular myocardial performance, independent of systolic blood pressure. Quantifying active systolic and diastolic compromise by derivation of myocardial work advances our understanding of pathophysiological processes in health and cardiac disease.},
  language  = {en}
}
@article{GuederWilkesmannScholzetal.2022,
  author    = {G{\"u}der, G{\"u}lmisal and Wilkesmann, Joana and Scholz, Nina and Leppich, Robert and D{\"u}king, Peter and Sperlich, Billy and Rost, Christian and Frantz, Stefan and Morbach, Caroline and Sahiti, Floran and Stefenelli, Ulrich and Breunig, Margret and St{\"o}rk, Stefan},
  title     = {Establishing a cardiac training group for patients with heart failure: the "HIP-in-W{\"u}rzburg" study},
  series = {Clinical Research in Cardiology},
  volume    = {111},
  journal   = {Clinical Research in Cardiology},
  issn      = {1861-0692},
  doi       = {10.1007/s00392-021-01892-1},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-266678},
  pages     = {406-415},
  year      = {2022},
  abstract  = {Background Exercise training in heart failure (HF) is recommended but not routinely offered, because of logistic and safety-related reasons. In 2020, the German Society for Prevention\&Rehabilitation and the German Society for Cardiology requested establishing dedicated ""HF training groups."" Here, we aimed to implement and evaluate the feasibility and safety of one of the first HF training groups in Germany. Methods Twelve patients (three women) with symptomatic HF (NYHA class II/III) and an ejection fraction ≤ 45\% participated and were offered weekly, physician-supervised exercise training for 1 year. Patients received a wrist-worn pedometer (M430 Polar) and underwent the following assessments at baseline and after 4, 8 and 12 months: cardiopulmonary exercise test, 6-min walk test, echocardiography (blinded reading), and quality of life assessment (Kansas City Cardiomyopathy Questionnaire, KCCQ). Results All patients (median age [quartiles] 64 [49; 64] years) completed the study and participated in 76\% of the offered 36 training sessions. The pedometer was worn ≥ 1000 min per day over 86\% of the time. No cardiovascular events occurred during training. Across 12 months, NT-proBNP dropped from 986 pg/ml [455; 1937] to 483 pg/ml [247; 2322], and LVEF increased from 36\% [29;41] to 41\% [32;46]\%, (p for trend = 0.01). We observed no changes in exercise capacity except for a subtle increase in peak VO2\% predicted, from 66.5 [49; 77] to 67 [52; 78]; p for trend = 0.03. The physical function and social limitation domains of the KCCQ improved from 60 [54; 82] to 71 [58; 95, and from 63 [39; 83] to 78 [64; 92]; p for trend = 0.04 and = 0.01, respectively. Positive trends were further seen for the clinical and overall summary scores. Conclusion This pilot study showed that the implementation of a supervised HF-exercise program is feasible, safe, and has the potential to improve both quality of life and surrogate markers of HF severity. This first exercise experiment should facilitate the design of risk-adopted training programs for patients with HF.},
  language  = {en}
}
@article{HennegesMorbachSahitietal.2022,
  author    = {Henneges, Carsten and Morbach, Caroline and Sahiti, Floran and Scholz, Nina and Frantz, Stefan and Ertl, Georg and Angermann, Christiane E. and St{\"o}rk, Stefan},
  title     = {Sex-specific bimodal clustering of left ventricular ejection fraction in patients with acute heart failure},
  series = {ESH Heart Failure},
  volume    = {9},
  journal   = {ESH Heart Failure},
  number    = {1},
  doi       = {10.1002/ehf2.13618},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-265839},
  pages     = {786-790},
  year      = {2022},
  abstract  = {Aims There is an ongoing discussion whether the categorization of patients with heart failure according to left ventricular ejection fraction (LVEF) is scientifically justified and clinically relevant. Major efforts are directed towards the identification of appropriate cut-off values to correctly allocate heart failure-specific pharmacotherapy. Alternatively, an LVEF continuum without definite subgroups is discussed. This study aimed to evaluate the natural distribution of LVEF in patients presenting with acutely decompensated heart failure and to identify potential subgroups of LVEF in male and female patients. Methods and results We identified 470 patients (mean age 75 ± 11 years, n = 137 female) hospitalized for acute heart failure in whom LVEF could be quantified by Simpson's method in an in-hospital echocardiogram. Non-parametric modelling revealed a bimodal shape of the LVEF distribution. Parametric modelling identified two clusters suggesting two LVEF peaks with mean (variance) of 61\% (9\%) and 31\% (10\%), respectively. Sub-differentiation by sex revealed a sex-specific bimodal clustering of LVEF. The respective threshold differentiating between 'high' and 'low' LVEF was 45\% in men and 52\% in women. Conclusions In patients presenting with acute heart failure, LVEF clustered in two subgroups and exhibited profound sex-specific distributional differences. These findings might enrich the scientific process to identify distinct subgroups of heart failure patients, which might each benefit from respectively tailored (pharmaco)therapies.},
  language  = {en}
}
@article{MorbachBeyersdorfKerkauetal.2021,
  author    = {Morbach, Caroline and Beyersdorf, Niklas and Kerkau, Thomas and Ramos, Gustavo and Sahiti, Floran and Albert, Judith and Jahns, Roland and Ertl, Georg and Angermann, Christiane E. and Frantz, Stefan and Hofmann, Ulrich and St{\"o}rk, Stefan},
  title     = {Adaptive anti-myocardial immune response following hospitalization for acute heart failure},
  series = {ESC Heart Failure},
  volume    = {8},
  journal   = {ESC Heart Failure},
  number    = {4},
  doi       = {10.1002/ehf2.13376},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-258907},
  pages     = {3348-3353},
  year      = {2021},
  abstract  = {Aims It has been hypothesized that cardiac decompensation accompanying acute heart failure (AHF) episodes generates a pro-inflammatory environment boosting an adaptive immune response against myocardial antigens, thus contributing to progression of heart failure (HF) and poor prognosis. We assessed the prevalence of anti-myocardial autoantibodies (AMyA) as biomarkers reflecting adaptive immune responses in patients admitted to the hospital for AHF, followed the change in AMyA titres for 6 months after discharge, and evaluated their prognostic utility. Methods and results AMyA were determined in n = 47 patients, median age 71 (quartiles 60; 80) years, 23 (49\%) female, and 24 (51\%) with HF with preserved ejection fraction, from blood collected at baseline (time point of hospitalization) and at 6 month follow-up (visit F6). Patients were followed for 18 months (visit F18). The prevalence of AMyA increased from baseline (n = 21, 45\%) to F6 (n = 36, 77\%; P < 0.001). At F6, the prevalence of AMyA was higher in patients with HF with preserved ejection fraction (n = 21, 88\%) compared with patients with reduced ejection fraction (n = 14, 61\%; P = 0.036). During the subsequent 12 months after F6, that is up to F18, patients with newly developed AMyA at F6 had a higher risk for the combined endpoint of death or rehospitalization for HF (hazard ratio 4.79, 95\% confidence interval 1.13-20.21; P = 0.033) compared with patients with persistent or without AMyA at F6. Conclusions Our results support the hypothesis that AHF may induce patterns of adaptive immune responses. More studies in larger populations and well-defined patient subgroups are needed to further clarify the role of the adaptive immune system in HF progression.},
  language  = {en}
}
@article{SahitiMorbachCejkaetal.2021,
  author    = {Sahiti, Floran and Morbach, Caroline and Cejka, Vladimir and Albert, Judith and Eichner, Felizitas A. and Gelbrich, G{\"o}tz and Heuschmann, Peter U. and St{\"o}rk, Stefan},
  title     = {Left Ventricular Remodeling and Myocardial Work: Results From the Population-Based STAAB Cohort Study},
  series = {Frontiers in Cardiovascular Medicine},
  volume    = {8},
  journal   = {Frontiers in Cardiovascular Medicine},
  issn      = {2297-055X},
  doi       = {10.3389/fcvm.2021.669335},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-240480},
  year      = {2021},
  abstract  = {Introduction: Left ventricular (LV) dilatation and LV hypertrophy are acknowledged precursors of myocardial dysfunction and ultimately of heart failure, but the implications of abnormal LV geometry on myocardial function are not well-understood. Non-invasive LV myocardial work (MyW) assessment based on echocardiography-derived pressure-strain loops offers the opportunity to study detailed myocardial function in larger cohorts. We aimed to assess the relationship of LV geometry with MyW indices in general population free from heart failure. Methods and Results: We report cross-sectional baseline data from the Characteristics and Course of Heart Failure Stages A-B and Determinants of Progression (STAAB) cohort study investigating a representative sample of the general population of W{\"u}rzburg, Germany, aged 30-79 years. MyW analysis was performed in 1,926 individuals who were in sinus rhythm and free from valvular disease (49.3\% female, 54 ± 12 years). In multivariable regression, higher LV volume was associated with higher global wasted work (GWW) (+0.5 mmHg\% per mL/m\(^2\), p < 0.001) and lower global work efficiency (GWE) (-0.02\% per mL/m\(^2\), p < 0.01), while higher LV mass was associated with higher GWW (+0.45 mmHg\% per g/m\(^2\), p < 0.001) and global constructive work (GCW) (+2.05 mmHg\% per g/m\(^2\), p < 0.01) and lower GWE (-0.015\% per g/m\(^2\), p < 0.001). This was dominated by the blood pressure level and also observed in participants with normal LV geometry and concomitant hypertension. Conclusion: Abnormal LV geometric profiles were associated with a higher amount of wasted work, which translated into reduced work efficiency. The pattern of a disproportionate increase in GWW with higher LV mass might be an early sign of hypertensive heart disease.},
  language  = {en}
}