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1291 citation(s) found for "Wu, Erik".

STELLAR: Phase III, Randomized, Open-Label Study of Eflornithine Plus Lomustine Versus Lomustine Alone in Patients With Recurrent Grade 3 Astrocytoma
Colman, Howard , Lombardi, Giuseppe , Wong, Eric T. , Walbert, Tobias , Lassman, Andrew B. , Peereboom, David M. , Kizilbash, Sani H. , Matsuoka, Carlos Kamiya , Pitz, Marshall , Desjardins, Annick , Kumthekar, Priya , Mason, Warren , Pellerino, Alessia , Butowski, Nicholas , Hamza, Mohamed A. , Lallana, Enrico C., Uhlmann, Erik J. , Welsh, Liam , Wen, Patrick Y. , Dietrich, Jörg , Wang, Chao , Levin, Victor A. , Lassman, Andrew B , Peereboom, David M , Kizilbash, Sani H , Kamiya-Matsuoka, Carlos , Pitz, Marshall W , Strowd, Roy E , Desjardins, Annick , Kumthekar, Priya , Mason, Warren , Pellerino, Alessia , Soffietti, Riccardo , Butowski, Nicholas A , Forsyth, Peter A , Hamza, Mohamed A , Hau, Peter , Nabors, Louis Burt , Uhlmann, Erik J , Welsh, Liam C , Wen, Patrick Yung , Dietrich, Jorg , Wang, Chao , Levin, Victor A , Colman, Howard , Eoli, Marica , Strowd, Roy E. , Soffietti, Riccardo , Hau, Peter , Nabors, Burt , Piccioni, David Eric , Lombardi, G

Journal of Clinical Oncology | December 1, 2025 | Volume: 44 | Issue: 8 | Pages: 641-652

10.1200/jco-25-01204 | PMID 41325560 Get It

PURPOSE STELLAR (ClinicalTrials.gov identifier: NCT02796261 ) was a phase III, randomized, open-label trial of eflornithine + lomustine versus lomustine monotherapy in patients with recurrent grade 3 astrocytoma. METHODS At trial initiation, eligibility criteria included: age ≥18 years, anaplastic astrocytoma (2016 WHO CNS Tumor classification [WHO CNS4]), first recurrence ≥6 months after radiation and temozolomide (TMZ), Karnofsky performance status ≥70, and no imaging findings consistent with grade 4 glioblastoma. Random assignment (1:1) was stratified by isocitrate dehydrogenase ( IDH ) mutation, age, resection extent, and geography. Patients received eflornithine (2.8 g/m 2 orally, every 8 hours [2 weeks on, 1 week off]) + lomustine (90 mg/m 2 orally, once every 6 weeks), or lomustine monotherapy (110 mg/m 2 once every 6 weeks). The primary end point was overall survival (OS). RESULTS Among 343 patients randomly assigned across 74 sites in eight countries, there was no difference in survival between eflornithine + lomustine and lomustine monotherapy (median OS 23.4 v 20.3 months, hazard ratio [HR], 0.94). Following changes in classification and grading in the 2021 WHO CNS5, a subset analysis of patients with IDH- mutant, grade 3 astrocytoma (n = 196), defined in 2024, before unblinding, showed clinically meaningful improvements in median OS with eflornithine + lomustine versus lomustine monotherapy (34.9 v 23.5 months, HR, 0.64) and median progression-free survival (PFS, 15.8 v 7.2 months, HR, 0.57). No differences were observed among patients with CNS grade 4 disease. Grade ≥3 treatment-emergent adverse events of relevance were related to reversible myelosuppression (eflornithine + lomustine 42% v lomustine monotherapy 29% of patients) and hearing impairment (24% v 0%). No new safety signals were identified. CONCLUSION Clinically meaningful improvements were observed; eflornithine + lomustine doubled PFS and improved OS in patients with recurrent IDH -mutant, grade 3 astrocytoma, but not grade 4 tumors, after prior radiotherapy and TMZ, consistent with its cytostatic mechanism of action.
Assembly of a Serial Link Test Vehicle Using Flip-Chip, SMT, and BGA Attach Processes: A Case Study
Wilkins, Wendy, Gilbert, Barry K., Daniel, Erik S.

Pan Pacific Symposium | December 1, 2025 | Volume: 10 | Issue: 1 | Pages: No page available

10.37665/ppbmwzy57193 Get It

ABSTRACT The Mayo Foundation Special Purpose Processor Development Group has been supporting a serial link development effort. In order to characterize serial link performance, two versions of a multi-chip module (MCM) test vehicle were assembled to study the effects of the substrate and the integrated circuit input/output buffer technologies on basic signal integrity performance parameters at data rates of 2.5 GHz. The difference between the test vehicles was the substrate technology used: ceramic and laminate. This paper describes the steps taken to develop an assembly process for the ceramic version of the test vehicle. The ceramic test vehicle consisted of a high thermal coefficient of expansion ceramic substrate, 2 CMOS chips with IBM high lead content (hereafter: “high lead”) bumps, 16 surface mount (SMT) capacitors, and an interposer. Assembly processes needed to be developed for SMT attach of the capacitors, flip-chip attach of the chips, and ball grid array (BGA) attach of the interposer. Based on Mayo's suite of assembly equipment, three process flows could have been used to attach the capacitors and the chips to the substrate: High lead attach of the capacitors and chips; Eutectic attach of capacitors, high lead attach of chips; Eutectic attach of the capacitors and chips. Assembly process flow 1 required the least number of steps. Therefore, it was initially selected as the process flow. However, this process flow was found to be unsatisfactory due to problems with flux charring around the capacitors and a high incidence of chip to substrate opens. Assembly process flow 2 was then evaluated. Assembly process flow 3 was considered the least desirable because eutectic solder paste had to be coated on the substrate die pads and Mayo did not have capability to do this. In order to develop the capacitor and die attach processes and to set up the interposer attach process, two assembly test vehicles were built on glass substrates. A capacitor attach process was devised that involved stenciling the eutectic solder paste, placing the capacitors, and then reflowing the assembly. The flip-chip attach process development required greater effort. Experimental matrices were run that allowed an assessment of bond strength as a function of flux quantity, bond force, and reflow temperature and time. Water-soluble flux was used for the chip attach process, so a de-fluxing process had to be developed. The chips then needed to be underfilled. The underfill dispense pattern and substrate heating were evaluated. The interposer was attached using eutectic solder paste stenciled on the back of the substrate. A BGA style attach process was set up to do this. The result of this process development activity was the successful assembly of 21 modules with no defects. Lessons were learned during the assembly process development regarding the difficulties associated with attaching components with high lead solder.
Temporal Elements of Speech in Mania
Joyce, Jeremiah B. , Joyce, Jeremiah , Ayala, Ivan N. , Chatzisofroniou, George, Clemens, Erik , Yu, Hang , Kendall, Tyler S. , Attia, Zachi, Lin, Baihan , Frye, Mark A.

No container title available | November 26, 2025 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.21203/rs.3.rs-7613536/v1 Get It

Abstract Computational analysis of speech enables precise, objective measurements of a behavioral signal closely linked to manic episodes. In a prospective cohort study conducted in Rochester, MN ( ClinicalTrials.gov Identifier: NCT05956340 ) , eighteen English-speaking adults voluntarily hospitalized for a manic episode of Bipolar I Disorder between August 2023 and September 2024 were enrolled. Participants completed semi-structured research interviews during both acute episodes and remission, with manic symptom severity assessed at each session using the Young Mania Rating Scale (YMRS). Across 57 recorded interviews, temporal prosodic features were extracted using automated computational algorithms. After adjusting for individual differences and moderating effects, participant articulation rate (β = 0.24, p = 0.0038), speech rate variability (β = 0.23, p = 0.0041), floor transfer offset (β = -0.31, p = 0.007), and speaking duration (β = 0.54, p < 0.001) were significantly associated with manic symptom severity. These temporal elements classified manic (CV AUC = 0.85) and remission (CV AUC = 0.83) status, highlighting their potential as monitoring and prognostic biomarkers for manic episodes.
Daily locomotor activity declines with tumor growth and disease progression in glioblastoma
Gonzalez-Aponte, Maria F. , Salvatore, Sofia V. , Damato, Anna R. , Katumba, Ruth , Talcott, Grayson, Butt, Omar H. , Campian, Jian , Luo, Jingqin , Walch, Olivia , Luo, Jingqin , Rubin, Joshua B , Herzog, Erik D.

JCI Insight | November 25, 2025 | Volume: 11 | Issue: 1 | Pages: No page available

10.1172/jci.insight.194582 | PMID 41289012 Get It

Glioblastoma (GBM) is an aggressive brain tumor that often progresses despite resection and treatment. Timely and continuous assessment of GBM progression is critical to expedite secondary surgery or enrollment in clinical trials. However, current progression detection requires costly and specialized MRI examinations, which, in the absence of new symptoms or signs, are usually scheduled every 2–3 months. Here, we hypothesized that changes in daily activity are associated with GBM growth and disease progression. We found that wheel-running activity in GBM-bearing mice declined as tumors grew and preceded weight loss and circadian breakdown by over a week. Temozolomide treatment in the morning, but not evening, significantly reduced tumor size and restored daily locomotion in mice. In a pilot study of 6 patients with GBM wearing an actigraphy watch, wrist movement provided a feasible and continuous longitudinal indicator of daily activity with 1-minute resolution. After tumor resection and radiation, daily activity declined in 2 patients 19 and 55 days before detection of progression by MRI but did not change for the 4 patients with stable disease. These results suggest that daily activity tracking using wearable devices may serve as a real-time indicator and potential monitoring tool for GBM progression and treatment efficacy.
Induction of Antigen-Specific T Cell Tolerance by CNP-104 Positively Affects Clinical Response in Primary Biliary Cholangitis (PBC) 9237
Elhofy, Adam, Frey, Molly , McCarthy, Derrick , Wambre, Erik , Caldwell, Stephen H. , Firpi-Morell, Roberto , Fortune, Brett E. , Galambos, Michael, Harnois, Denise M. , Hassanein, Tarek , Läwitz, E., Patel, Bhaktasharan, Phillips, Raymond E. , Pratt, Daniel S. , Pruthi, Jatinder, Rajendiran, Govarthanan , Reddy, Gautham, Rodrı́guez, Manuel, Silveira, Marina , Zervos, Bobby, Peloso, Paul M. , Gershwin, M. Eric, Bowlus, Christopher L. , Gordon, Stuart J. G. , Kappus, Matthew R. , Mchenry, Scott A. , Phillips, Raymond, Rodriguez, Manuel, Silveira, Marina

The Journal of Immunology | November 21, 2025 | Volume: 214 | Issue: Supplement_1 | Pages: No page available

10.1093/jimmun/vkaf283.2663 Get It

Abstract Description PBC is an archetypal autoimmune disease where the dominant autoantigen is mitochondrial PDC-E2. Hitherto, PBC treatment has been neither specific nor directed toward restoration of tolerance. CNP-104, a tolerogenic nanoparticle encapsulating PDC-E2, is hypothesized to restore tolerance to pathogenic T cells. We conducted a Phase 2a First-in-Human randomized controlled trial of CNP-104 in PBC patients unresponsive/intolerant to ursodeoxycholic acid. The 42 enrolled subjects were randomized 2:1 to receive two doses of CNP-104 or placebo (PBO) one week apart and were followed for 120 days to assess safety and treatment durability. CNP-104 was safe and well-tolerated. Compared to PBO, the CNP-104 group had a reduced percentage of antigen-specific Th17 T cells and increased antigen-specific tolerogenic CD8+ T cell counts (TIGIT, GARP). ALP, ALT, and total bilirubin were similar between groups. Clinically relevant effects on albumin levels, liver stiffness, and the rate of change in 5-year UK-PBC risk for liver outcomes were improved in the CNP-104 group compared to PBO. This trial is limited by small size and data variability. Induction of antigen-specific T cell tolerance, shown by reduced Th17 cells and increased TIGIT and GARP cells correlates with improved liver stiffness, albumin, and UK-PBC. These findings suggest the CNP-104 tolerogenic mechanism of action translates to clinical benefits. These data support future studies with this unique therapeutic platform to treat PBC. Topic Categories Therapeutic Approaches to Autoimmunity (THER)
Functional and Structural Connectivity Correlates of Axial Symptom Outcomes After Pallidal Deep Brain Stimulation in Parkinson’s Disease
Garcia, Gilberto Perez Rodriguez , Middlebrooks, Erik H. , Tsuboi, Takashi , Burns, Matthew R. , Ramirez‐Zamora, Adolfo , Perez Rodriguez Garcia, Gilberto , Middlebrooks, Erik H , Tsuboi, Takashi , Ramirez-Zamora, Adolfo , Mei, Shanshan , Wong, Joshua K. , Hemptinne, Coralie de

Brain Sciences | November 20, 2025 | Volume: 15 | Issue: 11 | Pages: 1245

10.3390/brainsci15111245 | PMID 41300251 Get It

Background/Objectives: Deep brain stimulation (DBS) of the globus pallidus interna (GPi) is a safe and established therapy for management of refractory motor fluctuations and dyskinesia in Parkinson’s disease (PD). However, the relationship between stimulation site connectivity and improvement of axial gait symptoms remains poorly understood, particularly when stimulating in the GPi. This study investigated functional and structural connectivity patterns specifically associated with axial symptom outcomes following bilateral GPi-DBS, and, as a secondary exploratory analysis, examined whether Volumes of tissue activated (VTAs)-based connectivity related to overall UPDRS-III change. Methods: We retrospectively analyzed 19 PD patients who underwent bilateral GPi-DBS at the University of Florida (2002–2017). Unified Parkinson’s Disease Rating Scale (UPDRS-III) axial gait subscores were assessed at baseline and 36-month follow-up. VTAs were reconstructed using Lead-DBS and coregistered to Montreal Neurological Institute (MNI) space. Structural connectivity was evaluated with diffusion tractography, and functional connectivity was estimated using normative resting-state fMRI datasets. Correlations between VTA connectivity and clinical improvement were examined using Spearman correlation and voxelwise analyses. Results: Patients with axial improvement in motor scales demonstrated specific VTA connectivity to sensorimotor and supplementary motor networks, particularly lobule V and lobules I–IV of the cerebellum. These associations were specific to axial gait subscores. In contrast, worsening axial gait symptoms correlated with connectivity to cerebellar Crus II, cerebellum VIII, calcarine cortex, and thalamus (p < 0.05). Total UPDRS-III scores did not show a significant positive correlation with supplementary motor area or primary motor cortex connectivity; a non-significant trend was observed for VTA–M1 connectivity (R = 0.41, p = 0.078). Worsening total motor scores were associated with cerebellar Crus II and frontal–parietal networks. These findings suggest that distinct connectivity patterns underlie differential trajectories in axial and global motor outcomes following GPi-DBS. Conclusions: Distinct connectivity profiles might underlie axial gait symptom outcomes following GPi-DBS. Connectivity to motor and sensorimotor pathways supports improvement, whereas involvement of Crus II and occipital networks predicts worsening. Additional studies to confirm and expand on these findings are needed, but our results highlight the value of connectomic mapping for refining patient-specific targeting and developing future programming strategies.
Pediatric Dermatology Learning Needs Identified Through Continuing Certification Program Assessments of the American Board of Dermatology
Stratman, Erik J. , Schaffer, Julie V., Miller, Stanley J., Bruckner, Anna L. , González, Mercedes E. , Zaenglein, Andrea L. , Roenigk, Randall K.

Pediatric Dermatology | November 19, 2025 | Volume: 43 | Issue: 3 | Pages: 650-653

10.1111/pde.70076 | PMID 41257358 Get It

ABSTRACT The American Board of Dermatology (ABD) Continuing Certification Program (CCP) for board‐certified dermatologists helps advance its vision, which includes quarterly web‐based knowledge assessments. In 2022, the ABD began a review of gaps in knowledge assessment, practice improvement reporting, and areas of educational interest. The American Board of Medical Specialties directed member boards to share frequently occurring deficits with specialty societies to identify and prioritize gaps. This report summarizes pediatric dermatology findings from this review.
A framework for using DNA methylation-based modelling for the clinical management of cranial meningioma
Landry, Alexander , Wang, Justin Z. , Patil, Vikas, Ajisebutu, Andrew, Gui, Chloe , Yefet, Leeor, Mamatjan, Yasin , Wei, Qingxia , Singh, Olivia, Mansouri, Sheila , Ehret, Felix , Capper, David , Cohen-Gadol, Aaron A, Behling, Felix , Sloan, Andrew E. , Chambless, Lola B. , Makarenko, Serge , Yip, Stephen , Tsang, Derek S. , Gao, Andrew , Aldape, Kenneth , Nassiri, Farshad , Zadeh, Gelareh , Santarius, Thomas , Selman, Warren R., Couce, Marta , Wen, Patrick Y. , Walbert, Tobias , Felicella, Michelle M. , Brodie, Chaya , Snyder, James P., Saladino, Andrea , Schichor, Christian , Tonn, Jörg‐Christian, Goldbrunner, Roland , Timmer, Marco , Schimdt, Nils Ole, Jenkinson, Michael D. , Millward, Christopher P. , Islim, Abdurrahman I. , Fl, Behling, Santacroce, Antonio , Schittenhelm, Jens , Raleigh, David R. , Butowski, Nicholas , Westphal, Manfred , Lamszus, Katrin , Mawrin, Christian , Kurz, Sylvia C. , Zada, Gabriel , Yip, Stephen, Zherebitskiy, Viktor, Hnenny, Luke, Dunn, Ian F. , Moliterno, Jennifer , McDermott, Michael , Vogelbaum, Michael A. , Aldape, Kenneth, Alkividias, Tzannis, Short, Susan , Bos, Eelke M. , Dincer, Alper , Paßlack, Peter, Ehret, Felix, Lopez, Clara, Arvaniti, Christina , Benjamin, Carolina , Jackson, Christina , Jeyaretna, Sanjeeva, Scartoni, Daniele , Amelio, Dante , Ivanidze, Jana , Kien, Duong Trung, Millareschavez, Miguel, AlThgafi, Malak, LeRhun, Emilie, Smee, Robert, Muirhead, William , Molina, Eric Suero, Julius, Vitowanu, Chen, J., Mrugała, Maciej M. , Castro, Ana Valeria , Mamatjan, Yasin , Capper, David , Tatagiba, Marcos , Barnholtz-Sloan, Jill S , Yip, Stephen , Aldape, Kenneth , Zadeh, Gelareh , Short, Susan C , Yefet, Leeor S. , Ellenbogen, Yosef , Liu, Jeff , Singh, Olivia , Tabatabai, Ghazaleh , Tatagiba, Marcos , Barnholtz‐Sloan, Jill S. , Mansouri, Alireza , Brastianos, Priscilla K. , Shih, Helen A. , Bi, Wenya Linda , Huang, Raymond Y. , Wen, Patrick Yung , Lee, Ian , Malta, Tathiane Maistro , Castro, Ana Valéria , Noushmehr, Houtan , DiMeco, Francesco , Pollo, Bianca , Kaufmann, Timothy J. , Lachance, Daniel Honore , Giannini, Caterina , Galanis, Evanthia , Raghunathan, Aditya , Hanemann, C. Oliver , Au, Karolyn , Galldiks, Norbert , Herold‐Mende, Christel C. , Sahm, Felix , Jungk, Christine , Jungwirth, Gerhard , Deimling, Andreas von , Drummond, Katharine Jann , Morokoff, Andrew P. , Renovanz, Mirjam , Fougère, Christian la , Perry, Arie , Ricklefs, Franz , Horbinski, Craig , Ng, Ho‐Keung , Snuderl, Matija , Sulman, Erik P. , Cohen‐Gadol, Aaron , Javadpour, Mohsen , Fountain, Daniel Mark , Mathiesen, Tiit Illimar , Pathmanaban, Omar Nathan , Boutros, Paul C. , Fountas, Konstantinos N. , Walsh, Kyle M. , Carvalho, Bruno , Maas, Sybren L. N. , Deng, Maximilian Y. , Mehta, Minesh P. , Odia, Yazmín , Everson, Richard G. , Balogun, James , Calabrese, Evan , Karschnia, Philipp , Teske, Nico , Fariselli, Laura , Greve, Tobias , Ivan, Michael E , Palmer, Joshua D. , Ostrom, Quinn T. , Youngblood, Mark W. , Emerson, Sam, Weller, Michael , Martínez-Pérez, Rafael , Mukherjee, Raj, Cervio, Andrés , Turner, Clinton P. , Chen, Jiawei, Karmur, Brij S. , Neth, Bryan J.

Neuro-Oncology | November 15, 2025 | Volume: 28 | Issue: 2 | Pages: 430-439

10.1093/neuonc/noaf237 | PMID 41259653 Get It

Abstract Background DNA methylation profiling can be used to robustly predict postsurgical outcomes and response to radiotherapy (RT) for meningioma patients. To allow for seamless integration of these complementary models into clinical practice, a practical framework is needed. Methods We leveraged a cohort of nearly 2000 surgically-treated meningiomas with DNA methylation profiling and clinical outcomes data. Existing methylation-based prediction models were dichotomized to yield four risk groups: low and high recurrent risk, each with RT sensitive and resistant subgroups. Risk groups were correlated with progression-free survival in the context of existing biomarkers including extent of resection and WHO grade. Results We first demonstrated that all risk groups benefit from gross total resection. All “high-risk, RT sensitive” tumors (n = 306, 15.7%) also benefited from adjuvant RT: after GTR, median PFS increased from 4.68 (4.13-9.48) years to not reached (P = .003); after subtotal resection (STR), from 2.12 (1.59-3.02) to 4.09 (3.41-not reached) years (P = .004). “Low-risk, RT sensitive cases” (n = 1207, 61.8%) also benefited from RT after STR (median PFS 7.39 (6.66-12.8) vs. 16.53 (10.35-not reached) years, P = .03), suggesting that RT be considered in these patients. Neither “low-risk RT resistant” (n = 84, 4.3%) nor “high-risk RT resistant” (n = 356, 18.2%) cases benefited from RT, and the latter group was associated with universally poor outcomes. Conclusions We identify methylation-defined risk groups of meningioma for which additional benefit is gained from adjuvant RT, leading to a clinical decision-making framework for straightforward integration of molecular models into clinical practice.
Left ventricular transmural pressure: A predictor of left ventricle unloading in continuous flow left ventricular assist devices
Yousefzai, Rayan , Cathey, Brianna , Ahsan, Syed , Alansari, Hatem , Suarez, Erik E. , Akay, Mehmet H. , Kim, Ju H. , Kassi, Mahwash , Bhimaraj, Arvind , Reddy, Yogesh N.V. , Guha, Ashrith , Alansari, Hatem , Kassi, Mahwash , Reddy, Yogesh N, Nishimura, Rick , Patel, Khush , Tedford, Ryan J.

The International Journal of Artificial Organs | November 14, 2025 | Volume: 48 | Issue: 11 | Pages: 852-857

10.1177/03913988251388558 | PMID 41234005 Get It

Achieving optimal unloading in patients with left ventricular assist devices (LVADs) is associated with improved outcomes but remains unattainable in some cases. We retrospectively reviewed 33 patients with a HeartMate 3 LVAD who underwent speed optimization with concomitant echocardiography and right heart catheterization for inadequate left ventricular (LV) unloading between January 2016 and December 2023. Patients were stratified based on left ventricular transmural pressure (LVTMP) into two groups: LVTMP ⩽7 mmHg and LVTMP >7 mmHg using a median split approach. Pulmonary capillary wedge pressure (PCWP) decreased in both groups with increased LVAD speed; however, the mean PCWP change per 100 rpm was significantly smaller in patients with LVTMP ⩽7 mmHg (−0.50 vs −0.99 mmHg per 100 rpm, p = 0.003). Comparative analysis demonstrated LVTMP’s superiority over established RV markers, with the strongest interaction effect for predicting speed optimization response. Changes in cardiac output were similar between the two groups. In univariate analysis, multiple hemodynamic parameters were significantly associated with reduced LVTMP, including right atrial pressure (OR = 1.27, p = 0.036), TPG (OR = 1.25, p = 0.037), DPG (OR = 1.69, p = 0.012), and PAPi (OR = 0.35, p = 0.019).LVTMP, as a surrogate for true LV preload, particularly in the context of RV failure, may offer predictive value for the success or failure of LV unloading with LVAD speed optimization.
Quantification of Instantaneous Extension and Contraction of In Vivo Myocardial Fiber
Pao, Y. C., Ritman, Erik L.

Advances in Bioengineering | November 13, 2025 | Volume: No volume available | Issue: No issue available | Pages: 7-8

10.1115/imece1994-0779 Get It

Abstract A modified myocardium-blood composite model enables the temporal changes in instantaneous extension and contraction of in vivo myocardial fiber to be computed by using the measured blood volume fractions and wall thicknesses in the investigated left ventricular region. A 16 time-increment study of 6 dogs shows that myocardial fiber may undergo an average length change of 62% and −38% during the diastolic and systolic phases of cardiac cycle, respectively. Two comparable results had been obtained previously, but the new method is much simpler, removes the incompressibility assumption and takes into consideration the intravascular blood in the ventricular wall.