bluuebunny/crossref_metadata_2025_split huggingface dataset:
Exercise-induced shift in right ventricular contraction pattern: novel marker of athlete’s heart?
Authors: Lakatos Bálint Károly , Kiss Orsolya , Tokodi Márton , Tősér Zoltán , Sydó Nóra , Merkely Gergő , Babity Máté , Szilágyi Mónika , Komócsin Zsuzsanna , Bognár Csaba , Kovács Attila , Merkely Béla 
Published: September 2018

Data about the functional adaptation of the right ventricle (RV) to intense exercise are limited. Our aim was to characterize the RV mechanical pattern in top-level athletes using three-dimensional echocardiography. A total of 60 elite water polo athletes (19 ± 4 yr, 17 ± 6 h of training/wk, 50% women and 50% men) and 40 healthy sedentary control subjects were enrolled. We measured the RV end-diastolic volume index (RVEDVi) and ejection fraction (RVEF) using dedicated software. Furthermore, we determined RV global longitudinal (RV GLS) and circumferential strain (RV GCS) and the relative contribution of longitudinal ejection fraction (LEF) and radial ejection fraction (REF) to RVEF using the ReVISION method. Athletes also underwent cardiopulmonary exercise testing [O2 consumption (V̇o2)/kg]. Athletes had significantly higher RVEDVi compared with control subjects (athletes vs. control subjects, 88 ± 11 vs. 65 ± 10 ml/m2, P < 0.001); however, they also demonstrated lower RVEF (56 ± 4% vs. 61 ± 5%, P < 0.001). RV GLS was comparable between the two groups (−22 ± 5% vs. −23 ± 5%, P = 0.24), whereas RV GCS was significantly lower in athletes (−21 ± 4% vs. −26 ± 7%, P < 0.001). Athletes had higher LEF and lower REF contribution to RVEF (LEF/RVEF: 0.50 ± 0.07 vs. 0.42 ± 0.07, P < 0.001; REF/RVEF: 0.33 ± 0.08 vs. 0.45 ± 0.08, P < 0.001). Moreover, the pattern of RV functional shift correlated with V̇o2/kg (LEF/RVEF: r = 0.30, P < 0.05; REF/RVEF: r = −0.27, P < 0.05). RV mechanical adaptation to long-term intense exercise implies a functional shift; the relative contribution of longitudinal motion to global function was increased, whereas the radial shortening was significantly decreased, in athletes. Moreover, this functional pattern correlates with aerobic exercise performance, representing a potential new resting marker of an athlete’s heart. NEW & NOTEWORTHY Intensive regular physical exercise results in significant changes of right ventricular morphology and function. By separate quantification of the right ventricular longitudinal and radial function, a relative dominance of longitudinal motion and a decrease in radial motion can be observed compared with sedentary controls. Moreover, this contraction pattern correlates with cardiopulmonary fitness. According to these results, this functional shift of the right ventricle may represent a novel marker of an athlete’s heart.
Progression of myocardial ischemia leads to unique changes in immediate-early gene expression in the spinal cord dorsal horn
Authors: Saddic Louis A. , Howard-Quijano Kimberly , Kipke Jasmine , Kubo Yukiko , Dale Erica A. , Hoover Donald , Shivkumar Kalyanam , Eghbali Mansoureh , Mahajan Aman 
Published: September 2018

The pathological consequences of ischemic heart disease involve signaling through the autonomic nervous system. Although early activation may serve to maintain hemodynamic stability, persistent aberrant sympathoexcitation contributes to the development of lethal arrhythmias and heart failure. We hypothesized that as the myocardium reacts and remodels to ischemic injury over time, there is an analogous sequence of gene expression changes in the thoracic spinal cord dorsal horn, the processing center for incoming afferent fibers from the heart to the central nervous system. Acute and chronic myocardial ischemia (MI) was induced in a large animal model of Yorkshire pigs, and the thoracic dorsal horn of treated pigs, along with control nonischemic pigs, was harvested for transcriptome analysis. We identified 32 differentially expressed genes between healthy and acute ischemia cohorts and 46 differentially expressed genes between healthy and chronic ischemia cohorts. The canonical immediate-early gene c-fos was upregulated after acute MI, along with fosB, dual specificity phosphatase 1 and 2 ( dusp1 and dusp2), and early growth response 2 (egr2). After chronic MI, there was a persistent yet unique activation of immediate-early genes, including fosB, nuclear receptor subfamily 4 group A members 1−3 ( nr4a1, nr4a2, and nr4a3), egr3, and TNF-α-induced protein 3 ( tnfaip3). In addition, differentially expressed genes from the chronic MI signature were enriched in pathways linked to apoptosis, immune regulation, and the stress response. These findings support a dynamic progression of gene expression changes in the dorsal horn with maturation of myocardial injury, and they may explain how early adaptive autonomic nervous system responses can maintain hemodynamic stability, whereas prolonged maladaptive signals can predispose patients to arrhythmias and heart failure. NEW & NOTEWORTHY Activation of the autonomic nervous system after myocardial injury can provide early cardiovascular support or prolonged aberrant sympathoexcitation. The later response can lead to lethal arrhythmias and heart failure. This study provides evidence of ongoing changes in the gene expression signature of the spinal cord dorsal horn as myocardial injury progresses over time. These changes could help explain how an adaptive nervous system response can become maladaptive over time.
Whole-Genome Sequencing Reveals Elevated Tumor Mutational Burden and Initiating Driver Mutations in African Men with Treatment-Naïve, High-Risk Prostate Cancer
Authors: Jaratlerdsiri Weerachai , Chan Eva K.F. , Gong Tingting , Petersen Desiree C. , Kalsbeek Anton M.F. , Venter Philip A. , Stricker Phillip D. , Bornman M.S. Riana , Hayes Vanessa M. 
Published: September 2018

AbstractAfrican-American men are more likely than any other racial group to die from prostate cancer. The contribution of acquired genomic variation to this racial disparity is largely unknown, as genomic from Africa is lacking. Here, we performed the first tumor-normal paired deep whole-genome sequencing for Africa. A direct study-matched comparison between African- and European-derived, treatment-naïve, high-risk prostate tumors for 15 cases allowed for further comparative analyses of existing data. Excluding a single hypermutated tumor with 55 mutations per megabase, we observed a 1.8-fold increase in small somatic variants in African- versus European-derived tumors (P = 1.02e–04), rising to 4-fold when compared with published tumor-matched data. Furthermore, we observed an increase in oncogenic driver mutations in African tumors (P = 2.92e–03); roughly 30% of impacted genes were novel to prostate cancer, and 79% of recurrent driver mutations appeared early in tumorigenesis. Although complex genomic rearrangements were less frequent in African tumors, we describe a uniquely hyperduplicated tumor affecting 149 transposable elements. Comparable with African Americans, ERG fusions and PIK3CA mutations were absent and PTEN loss less frequent. CCND1 and MYC were frequently gained, with somatic copy-number changes more likely to occur late in tumorigenesis. In addition to traditional prostate cancer gene pathways, genes regulating calcium ion-ATPase signal transduction were disrupted in African tumors. Although preliminary, our results suggest that further validation and investigation into the potential implications for elevated tumor mutational burden and tumor-initiating mutations in clinically unfavorable prostate cancer can improve patient outcomes in Africa.Significance:The first whole-genome sequencing study for high-risk prostate cancer in African men allows a simultaneous comparison of ethnic differences relative to European populations and of the influences of the environment relative to African-American men.
PLK1 Inhibition Targets Myc-Activated Malignant Glioma Cells Irrespective of Mismatch Repair Deficiency–Mediated Acquired Resistance to Temozolomide
Authors: Higuchi Fumi , Fink Alexandria L. , Kiyokawa Juri , Miller Julie J. , Koerner Mara V.A. , Cahill Daniel P. , Wakimoto Hiroaki 
Published: September 2018

Abstract
Mismatch repair (MMR) deficiency through MSH6 inactivation has been identified in up to 30% of recurrent high-grade gliomas, and represents a key molecular mechanism underlying the acquired resistance to the alkylating agent temozolomide (TMZ). To develop a therapeutic strategy that could be effective in these TMZ-refractory gliomas, we first screened 13 DNA damage response modulators for their ability to suppress viability of MSH6-inactivated, TMZ-resistant glioma cells. We identified a PLK1 selective inhibitor, Volasertib, as the most potent in inhibiting proliferation of glioblastoma cells. PLK1 inhibition induced mitotic catastrophe, G2–M cell-cycle arrest, and DNA damage, leading to caspase-mediated apoptosis in glioblastoma cells. Importantly, therapeutic effects of PLK1 inhibitors were not influenced by MSH6 knockdown, indicating that their action is independent of MMR status of the cells. Systemic treatment with Volasertib potently inhibited tumor growth in an MMR-deficient, TMZ-resistant glioblastoma xenograft model. Further in vitro testing in established and patient-derived cell line panels revealed an association of PLK1 inhibitor efficacy with cellular Myc expression status. We found that cells with deregulated Myc are vulnerable to PLK1 inhibition, as Myc overexpression sensitizes, whereas its silencing desensitizes, glioblastoma cells to PLK1 inhibitors. This discovery is clinically relevant as glioma progression post-TMZ treatment is frequently accompanied by MYC genomic amplification and/or pathway activation. In conclusion, PLK inhibitor represents a novel therapeutic option for recurrent gliomas, including those TMZ-resistant from MMR deficiency. Genomic MYC alteration may serve as a biomarker for PLK inhibitor sensitivity, as Myc-driven tumors demonstrated pronounced responses.
Effect of Interventricular Electrical Delay on Atrioventricular Optimization for Cardiac Resynchronization Therapy
Authors: Gold Michael R. , Yu Yinghong , Singh Jagmeet P. , Birgersdotter-Green Ulrika , Stein Kenneth M. , Wold Nicholas , Meyer Timothy E. , Ellenbogen Kenneth A. 
Published: September 2018

Background:
Routine atrioventricular optimization (AVO) has not been shown to improve outcomes with cardiac resynchronization therapy (CRT). However, more recently subgroup analyses of multicenter CRT trials have identified electrocardiographic or lead positions associated with benefit from AVO. Therefore, the purpose of this analysis was to evaluate whether interventricular electrical delay modifies the impact of AVO on reverse remodeling with CRT.

Methods:
This substudy of the SMART-AV trial (SMARTDELAY Determined AV Optimization) included 275 subjects who were randomized to either an electrogram-based AVO (SmartDelay) or nominal atrioventricular delay (120 ms). Interventricular delay was defined as the time between the peaks of the right ventricular (RV) and left ventricular (LV) electrograms (RV-LV duration). CRT response was defined prospectively as a >15% reduction in LV end-systolic volume from implant to 6 months.

Results:

The cohort was 68% men, with a mean age of 65±11 years and LV ejection fraction of 28±8%. Longer RV-LV durations were significantly associated with CRT response (
P
<0.01) for the entire cohort. Moreover, the benefit of AVO increased as RV-LV duration prolonged. At the longest quartile, there was a 4.26× greater odds of a remodeling response compared with nominal atrioventricular delays (
P
=0.010).

Conclusions:
Baseline interventricular delay predicted CRT response. At long RV-LV durations, AVO can increase the likelihood of reverse remodeling with CRT. AVO and LV lead location optimized to maximize interventricular delay may work synergistically to increase CRT response.

Clinical Trial Registration:

URL:
https://www.clinicaltrials.gov
. Unique identifier: NCT00874445.
Risk of Appropriate Therapy and Death Before Therapy After Implantable Cardioverter-Defibrillator Generator Replacement
Authors: Witt Chance M. , Waks Jonathan W. , Mehta Ramila A. , Friedman Paul A. , Kramer Daniel B. , Buxton Alfred E. , Mulpuru Siva K. , Noseworthy Peter A. , Hodge David O. , Lushinsky Emilie C. , Mulholland Megan B. , Cha Yong-Mei , Gersh Bernard J. , Madhavan Malini 
Published: September 2018

Background
The decision to initially implant an implantable cardioverter-defibrillator (ICD) is informed by robust randomized controlled trials, but no such data exist to guide the decision to replace an ICD generator. In this study, we aimed to determine outcomes after ICD generator replacement.

Methods
All patients with ischemic or nonischemic cardiomyopathy who underwent ICD generator replacement from 2001 to 2011 at Mayo Clinic, MN, or Beth Israel Deaconess Medical Center, MA, were included. Outcomes included (1) appropriate therapy after generator replacement and (2) death before appropriate therapy after generator replacement. Cox proportional hazards modeling was used to determine the associations between patient characteristics and outcomes.

Results
In 1421 patients undergoing ICD generator replacement (mean±SD age 69.6±12.1 years, 81% male), appropriate therapy occurred after replacement in 435 patients (30.6%) over a mean follow-up of 2.7±2.6 years. Associated factors included lower left ventricular ejection fraction and history of appropriate therapy before generator replacement. Death before appropriate ICD therapy occurred in 336 (23.7%) patients. Older age, lower left ventricular ejection fraction, and noncardiac comorbidities, including diabetes mellitus, chronic lung disease, peripheral vascular disease, lower hemoglobin, and lower glomerular filtration rate, were associated with greater risk of death before appropriate therapy. A progressive increase in mortality was observed with aggregation of these noncardiac comorbidities.

Conclusions
The decision to replace the ICD should take into consideration not only left ventricular ejection fraction and history of ventricular arrhythmias, but also comorbid illnesses that may impact the duration and the quality of life.
Digoxin Is Associated With a Decreased Incidence of Angiodysplasia-Related Gastrointestinal Bleeding in Patients With Continuous-Flow Left Ventricular Assist Devices
Authors: Vukelic Sasa , Vlismas Peter P. , Patel Snehal R. , Xue Xiaonan , Shitole Sanyog G. , Saeed Omar , Sims Daniel B. , Chinnadurai Thiru , Shin Julia J. , Forest Stephen J. , Goldstein Daniel J. , Jorde Ulrich P. 
Published: September 2018

Background:
Gastrointestinal bleeding (GIB) is one of the principal adverse events affecting patients with continuous-flow left ventricular assist devices (CF-LVADs). Despite the early recognition that GIB is commonly because of gastrointestinal angiodysplasia (GIAD), the exact pathophysiology of this process remains elusive. It has been postulated that the abnormal hemodynamic profile in CF-LVAD patients may activate the angiogenesis signaling cascade via the HIF (hypoxia-inducible factor)-1α/angiopoietin-2 pathway leading to formation of GIADs. Digoxin is a potent inhibitor of HIF-1α synthesis, and we hypothesized that its use reduces the incidence of GIAD and GIB in patients with CF-LVAD.

Methods and Results:

Charts of all adult patients implanted with CF-LVAD between February 2006 and February 2017 were reviewed with particular emphasis on occurrence and cause of GIB. Fifty-four of 199 patients (27%) experienced a GIB. Overall frequency of GIB was lower in the 64 patients receiving digoxin compared with the 135 patients not receiving digoxin (16% versus 33%,
P
=0.01). Multivariable-adjusted Cox regression analysis confirmed that digoxin use was independently associated with a reduced risk for overall GIB (hazard ratio, 0.49; 95% CI, 0.24–0.98;
P
=0.045). GIBs were then categorized as non-GIAD, GIAD, or likely GIAD. Although the incidence of non-GIAD was similar in both groups (11% versus 7%,
P
=0.41), the frequency of GIAD/likely GIAD bleeding was significantly reduced in the digoxin group (5% versus 25%,
P
=0.0003). Multivariable-adjusted analysis confirmed that digoxin use was independently associated with a reduced risk for GIAD/likely GIAD bleeding (hazard ratio, 0.18; 95% CI, 0.06–0.6;
P
=0.005). However, digoxin use was not associated with reduced risk for non-GIAD GIB (hazard ratio, 1.54; 95% CI, 0.58–4.08;
P
=0.39).

Conclusions:
Use of digoxin was associated with a significant reduction in GIAD-related GIB in patients with CF-LVAD.
Abdominal Positioning of the Next-Generation Intra-Aortic Fluid Entrainment Pump (Aortix) Improves Cardiac Output in a Swine Model of Heart Failure
Authors: Annamalai Shiva K. , Esposito Michele L. , Reyelt Lara A. , Natov Peter , Jorde Lena E. , Karas Richard H. , Kapur Navin K. 
Published: September 2018

Background:
Acute heart failure refractory to medical therapy is a major cause of morbidity and mortality. The Aortix device (Procyrion Inc) is a percutaneously delivered entrainment pump positioned in the descending aorta.

Methods and Results:
Using the newest generation Aortix device in 8 adult male Yorkshire swine, we tested the hypothesis that positioning in the abdominal aorta may provide superior hemodynamic effects than thoracic positioning in a swine model of postinfarct left ventricular injury.Abdominal activation generated significantly larger transaortic gradients (proximal minus distal mean aortic pressures) than thoracic positioning at all pump speeds. Compared with baseline values, activation in the abdominal, not thoracic, position significantly increased cardiac output, reduced arterial elastance, and systemic vascular resistance at low speeds. Compared with baseline values, abdominal activation also increased transpulmonary pressure gradients at medium and high speed, which was driven by trends toward higher mean pulmonary artery pressure and lower pulmonary capillary wedge pressure.

Conclusions:
This is the first report to determine that in contrast to thoracic positioning, abdominal positioning of the newest generation Aortix device reduces left ventricular afterload and increases cardiac output at low speeds. These findings have potentially important implications for the design of early clinical studies by suggesting that device position and speed are major determinants of improved hemodynamic efficacy.
Neural Networks for Prognostication of Patients With Heart Failure
Authors: Hearn Jason , Ross Heather J , Mueller Brigitte , Fan Chun-Po , Crowdy Edgar , Duhamel Joe , Walker Mike , Alba Ana Carolina , Manlhiot Cedric 
Published: September 2018

BackgroundPrognostication of heart failure patients from cardiopulmonary exercise test (CPET) currently involves simplification of complex time-series data into summary indices. We hypothesized that prognostication could be improved by considering the totality of the data generated during a CPET, instead of using summary indices alone.Methods and ResultsComplete data from 1156 CPETs were used to predict clinical deterioration (characterized by initiation of mechanical circulatory support, listing for heart transplantation or mortality) 1 year post-CPET. We compared the prognostic value (area under the receiver operating characteristic curve) of (1) the most predictive summary indices, (2) staged data collected at discrete intervals using multivariable regression models, and (3) breath-by-breath data using a feedforward neural network. The top-performing models were compared with the commonly used CPET risk score, using absolute net reclassification index. All models were trained and assessed using a 100-iteration Monte Carlo cross-validation. A total of 190 (16.4%) patients experienced clinical deterioration. The summary indices demonstrated subpar discriminative value (area under the receiver operating characteristic curve ≤0.800). Each multivariable model outperformed the summary indices, with the neural network incorporating breath-by-breath data achieving the best performance (area under the receiver operating characteristic curve =0.842). When compared with the CPET risk score (area under the receiver operating characteristic curve =0.759), the top-performing model obtained a net reclassification index of 4.9%.ConclusionsThe current practice of considering summary indices in isolation fails to realize the full value of CPET data. This may lead to less accurate prognostication of patients and in consequence, inaccurate selection of patients for advanced therapy. Clinical practices, like CPET prognostication, must be continuously reevaluated to ensure optimal usage of valuable (and oft-underutilized) data sources.
Clinical Outcomes of Drug-Eluting Balloon for In-Stent Restenosis Based on the Number of Metallic Layers
Authors: Yabushita Hiroto , Kawamoto Hiroyoshi , Fujino Yusuke , Tahara Satoko , Horikoshi Takeo , Tada Miho , Amano Tatsuya , Onishi Hirokazu , Nakajima Akihiro , Warisawa Takayuki , Watanabe Yusuke , Yoshizaki Toru , Mitomo Satoru , Sato Tomohiko , Naganuma Toru , Ishiguro Hisaaki , Kurita Naoyuki , Nakamura Shotarou , Hozawa Koji , Nakamura Sunao 
Published: September 2018

Background:
This study assesses clinical outcomes after drug-eluting balloon treatment for recurrent in-stent restenosis lesions based on the number of metallic layers.

Methods and Results:

We enrolled 304 consecutive patients (333 lesions) treated with percutaneous coronary intervention using drug-eluting balloon for in-stent restenosis lesions between March 2014 and June 2015. Per the number of stent layers previously implanted to the lesion, the patients were categorized into 3 groups, 1 stent layer (1L), 166 patients; 2 stent layers (2L), 87 patients; and ≥3 stent layers (≥3L), 51 patients. The end points were major adverse cardiovascular events (MACE), including cardiac death, target lesion revascularization, myocardial infarction, and definite or probable stent thrombosis. No significant differences were observed in patients’ baseline characteristics among the groups. The 1-year MACE and target lesion revascularization rates were significantly higher in the ≥3L group than those in the 1L and 2L groups (MACE: 1L, 16.9%; 2L, 16.1%; and ≥3L, 43.1%,
P
<0.01; target lesion revascularization: 1L, 14.5%; 2L, 14.9%; and ≥3L, 41.2%,
P
<0.01). The multivariable Cox regression analysis revealed that the number of metallic layers (≥3L compared with 1L; hazard ratio, 3.17; [95% CI, 1.75–5.76];
P
<0.01 and hemodialysis [hazard ratio, 2.21; (95% CI, 1.12–4.36);
P
=0.02]) were independent predictors for MACE. No significant differences were observed in the occurrence of cardiac death among the groups (
P
=0.34).

Conclusions:
Seemingly, drug-eluting balloon is less effective for ≥3L in-stent restenosis lesions. Hemodialysis and in-stent restenosis with the number of metallic layers are independent predictors for MACE.