Classical theta constants vs. lattice theta series, and super string partition functions

Recently, various possible expressions for the vacuum-to-vacuum superstring amplitudes has been proposed at genus $g=3,4,5$. To compare the different proposals, here we will present a careful analysis of the comparison between the two main technical tools adopted to realize the proposals: the classical theta constants and the lattice theta series. We compute the relevant Fourier coefficients in order to relate the two spaces. We will prove the equivalence up to genus 4. In genus five we will show that the solutions are equivalent modulo the Schottky form and coincide if we impose the vanishing of the cosmological constant.Comment: 21 page

International Validation of Metabolic Exercise test data combined with Cardiac and Kidney Indexes (MECKI) Score in Heart Failure

Background: Current European heart failure (HF) Guidelines suggests the use of risk score: among them, the Metabolic Exercise test data combined with Cardiac and Kidney Indexes (MECKI) score has demonstrated to be one of the most accurate. However, the risk scores are still poorly implemented in clinical practice, also due to lack of strong evidence regarding their external validation in different populations. Thus, the current study was designed as an external validation test of the MECKI score in an international multicentre setting. Methods: The study cohort consisted of patients diagnosed with HF with reduced ejection fraction (HFrEF) across international centres (not Italian), retrospectively recruited. Collected data included demographics, HF aetiology, laboratory testing, ECG, echocardiographic findings, cardiopulmonary exercise testing (CPET) results as described in the original MECKI score publication. Results: 1042 patients across 8 international centres (7 European and 1 Asian) were included and followed up from 1998 till 2019. Patients were divided according to the calculated MECKI scores into 3 subgroups: (i) MECKI score <10%; (ii) 10-20%; (iii) ≥20%. Survival analysis comparison among the 3 MECKI score subgroups showed a worse prognosis in patients with higher MECKI score value: median event-free survival times were 4396 days for MECKI score <10%; 3457 days for 10-20%; 1022 days for ≥20% (p<0.0001). ROC curves and the AUC curves were like those reported in the original internal validation studies. Conclusion: In patients diagnosed with HFrEF, the power of the MECKI score was confirmed in terms of prognosis and risk stratification, supporting its implementation as advised by the HF Guidelines

Renal function and peak exercise oxygen consumption in chronic heart failure with reduced left ventricular ejection fraction

Background: Chronic kidney disease is associated with sympathetic activation and muscle abnormalities, which may contribute to decreased exercise capacity. We investigated the correlation of renal function with peak exercise oxygen consumption (V˙O2) in heart failure (HF) patients. Methods and Results: We recruited 2,938 systolic HF patients who underwent clinical, laboratory, echocardiographic and cardiopulmonary exercise testing. The patients were stratified according to estimated glomerular filtration rate (eGFR). Mean follow-up was 3.7 years. The primary outcome was a composite of cardiovascular death and urgent heart transplantation at 3 years. On multivariable regression, eGFR was predictor of peakV˙O2 (P&lt;0.0001). Other predictors were age, sex, body mass index, HF etiology, NYHA class, atrial fibrillation, resting heart rate, Btype natriuretic peptide, hemoglobin, and treatment. After adjusting for significant covariates, the hazard ratio for primary outcome associated with peakVO2 &lt;12 ml ・ kg−1 ・ min−1 was 1.75 (95% confidence interval (CI): 1.06–2.91; P=0.0292) in patients with eGFR ≥60, 1.77 (0.87–3.61; P=0.1141) in those with eGFR of 45–59, and 2.72 (1.01– 7.37; P=0.0489) in those with eGFR &lt;45 ml ・ min−1 ・ 1.73 m−2. The area under the receiver-operating characteristic curve for peakV˙O2 &lt;12 ml ・ kg−1 ・ min−1 was 0.63 (95% CI: 0.54–0.71), 0.67 (0.56–0.78), and 0.57 (0.47–0.69), respectively. Testing for interaction was not significant. Conclusions: Renal dysfunction is correlated with peakV O2. A peakV O2 cutoff of 12 ml ・ kg–1 ・ min–1 offers limited prognostic information in HF patients with more severely impaired renal function

Prognostic role of atrial fibrillation in patients affected by chronic heart failure. Data from the MECKI score research group

Atrial fibrillation (AF) is common in heart failure (HF). It is unclear whether AF has an independent prognostic role in HF. The aim of the present study was to assess the prognostic role of AF in HF patients with reduced ejection fraction (EF)

Pick Your Threshold: A Comparison Among Different Methods of Anaerobic Threshold Evaluation in Heart Failure Prognostic Assessment

In clinical practice, anaerobic threshold (AT) is used to guide training and rehabilitation programs, to define risk of major thoracic or abdominal surgery, and to assess prognosis in heart failure (HF). AT of oxygen uptake (V.O2; V.O2AT) has been reported as an absolute value (V.O2ATabs), as a percentage of predicted peak V.O2 (V.O2AT%peak_pred), or as a percentage of observed peak V.O2 (V.O2AT%peak_obs). A direct comparison of the prognostic power among these different ways to report AT is missing

Cardiovascular death risk in recovered mid-range ejection fraction heart failure. insights from cardiopulmonary exercise test

Background: Heart failure with midrange ejection fraction (HFmrEF) represents a heterogeneous category where phenotype, as well as prognostic assessment, remains still debated. The present study explores a specific HFmrEF subset, namely those who recovered from a reduced EF (rec-HFmrEF) and, particularly, it focuses on the possible additive prognostic role of cardiopulmonary exercise testing (CPET). Methods and results: We analyzed data of 4,535 HF with reduced EF (HFrEF) and 1,176 rec-HFmrEF outpatients from the Metabolic Exercise combined with Cardiac and Kidney Indexes (MECKI) database. The end-point was cardiovascular death at 5 years. The median follow-up was 1,343 days (25th-75th range, 627-2,403 days). Cardiovascular death occurred in 552 HFrEF and 61 rec-HFmrEF patients. The multivariate analysis confirmed an independent role of the MECKI score's variables in HFrEF (C-index=0.744) whereas, in the rec-HFmrEF group, only age and peak oxygen uptake (pVO2) remained associated to the end-point (C-index=0.745). A pVO2 ≤55% of predicted and a ventilatory efficiency ≥31 resulted as the most accurate cut-off values in the outcome prediction. Conclusions: Present data support the CPET and, particularly, the pVO2, as a useful tool in the rec-HFmrEF prognostic assessment. Peak VO2≤55% predicted and ventilatory efficiency ≥31 might help to identify a high risk rec-HFmrEF subgroup

Renal function and peak exercise oxygen consumption in chronic heart failure with reduced left ventricular ejection fraction

Chronic kidney disease is associated with sympathetic activation and muscle abnormalities, which may contribute to decreased exercise capacity. We investigated the correlation of renal function with peak exercise oxygen consumption (V̇O2) in heart failure (HF) patients. METHODS AND RESULTS: We recruited 2,938 systolic HF patients who underwent clinical, laboratory, echocardiographic and cardiopulmonary exercise testing. The patients were stratified according to estimated glomerular filtration rate (eGFR). Mean follow-up was 3.7 years. The primary outcome was a composite of cardiovascular death and urgent heart transplantation at 3 years. On multivariable regression, eGFR was predictor of peakV̇O2(P<0.0001). Other predictors were age, sex, body mass index, HF etiology, NYHA class, atrial fibrillation, resting heart rate, B-type natriuretic peptide, hemoglobin, and treatment. After adjusting for significant covariates, the hazard ratio for primary outcome associated with peakV̇O2<12 ml·kg(-1)·min(-1)was 1.75 (95% confidence interval (CI): 1.06-2.91; P=0.0292) in patients with eGFR ≥60, 1.77 (0.87-3.61; P=0.1141) in those with eGFR of 45-59, and 2.72 (1.01-7.37; P=0.0489) in those with eGFR <45 ml·min(-1)·1.73 m(-2). The area under the receiver-operating characteristic curve for peakV̇O2<12 ml·kg(-1)·min(-1)was 0.63 (95% CI: 0.54-0.71), 0.67 (0.56-0.78), and 0.57 (0.47-0.69), respectively. Testing for interaction was not significant

Does moderate hyperkalemia influence survival in HF? Insights from the MECKI score data base

The prognostic role of moderate hyperkalemia in reduced ejection fraction (HFrEF) patients is still controversial. Despite this, it affects the use of renin-angiotensin-aldosterone system inhibitors (RAASi) with therapy down-titration or discontinuation

Deceptive meaning of oxygen uptake measured at the anaerobic threshold in patients with systolic heart failure and atrial fibrillation

41Oxygen uptake at the anaerobic threshold (VO2AT), a submaximal exercise-derived variable, independent of patients' motivation, is a marker of outcome in heart failure (HF). However, previous evidence of VO2AT values paradoxically higher in HF patients with permanent atrial fibrillation (AF) than in those with sinus rhythm (SR) raised uncertainties.nonenoneMagrì, Damiano; Agostoni, Piergiuseppe; Corrà, Ugo; Passino, Claudio; Scrutinio, Domenico; Perrone-Filardi, Pasquale; Correale, Michele; Cattadori, Gaia; Metra, Marco; Girola, Davide; Piepoli, Massimo F; Iorio, AnnaMaria; Emdin, Michele; Raimondo, Rosa; Re, Federica; Cicoira, Mariantonietta; Belardinelli, Romualdo; Guazzi, Marco; Limongelli, Giuseppe; Clemenza, Francesco; Parati, Gianfranco; Frigerio, Maria; Casenghi, Matteo; Scardovi, Angela B; Ferraironi, Alessandro; Di Lenarda, Andrea; Bussotti, Maurizio; Apostolo, Anna; Paolillo, Stefania; La Gioia, Rocco; Gargiulo, Paola; Palermo, Pietro; Minà, Chiara; Farina, Stefania; Battaia, Elisa; Maruotti, Antonello; Pacileo, Giuseppe; Contini, Mauro; Oliva, Fabrizio; Ricci, Roberto; Sinagra, GianfrancoMagrì, Damiano; Agostoni, Piergiuseppe; Corrà, Ugo; Passino, Claudio; Scrutinio, Domenico; Perrone-Filardi, Pasquale; Correale, Michele; Cattadori, Gaia; Metra, Marco; Girola, Davide; Piepoli, Massimo F; Iorio, Annamaria; Emdin, Michele; Raimondo, Rosa; Re, Federica; Cicoira, Mariantonietta; Belardinelli, Romualdo; Guazzi, Marco; Limongelli, Giuseppe; Clemenza, Francesco; Parati, Gianfranco; Frigerio, Maria; Casenghi, Matteo; Scardovi, Angela B; Ferraironi, Alessandro; Di Lenarda, Andrea; Bussotti, Maurizio; Apostolo, Anna; Paolillo, Stefania; La Gioia, Rocco; Gargiulo, Paola; Palermo, Pietro; Minà, Chiara; Farina, Stefania; Battaia, Elisa; Maruotti, Antonello; Pacileo, Giuseppe; Contini, Mauro; Oliva, Fabrizio; Ricci, Roberto; Sinagra, Gianfranc

Heart failure and anemia: Effects on prognostic variables

Anemia is frequent in heart failure (HF), and it is associated with higher mortality. The predictive power of established HF prognostic parameters in anemic HF patients is unknown