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Alfredo Verastegui has a total of 95 co-authors. Here are the top co-authors by number of shared publications:


Latest Publications

  • Open Access

    Cardiometabolic and atherosclerotic cardiovascular disease outcomes associated with tirzepatide: insights from a 1-year multicenter observational study

    by Rene de J Rivera Gutierrez, Regina Castaneda, Alfredo Verastegui, Wissam Ghusn, Dima Bechenati, Maria A Espinosa, Jose Villamarin, Elif Tama, Kirsten Frederiksen, Andres Acosta, et al.

    Purpose: To evaluate the association of long-term, continuous tirzepatide use with cardiometabolic risk parameters and estimated 10-year atherosclerotic cardiovascular disease (ASCVD) risk in real-world practice. Methods: This multicenter retrospective observational study included 1028 adults with overweight or obesity who received weekly subcutaneous tirzepatide for at least 12 months within the Mayo Clinic Health System from June 2022 through May 2024. Atherosclerotic cardiovascular disease risk analyses included 275 individuals with complete baseline and 12-month follow-up data. Outcomes were changes in cardiometabolic parameters, estimated 10-year ASCVD risk, and ASCVD risk category. Results: At 12 months, median total body weight loss (TBWL) was 12.6%. Fasting glucose, HbA1c, triglycerides, and alanine aminotransferase decreased by 19.5%, 16.0%, 8.5%, and 10.6%, respectively, whereas HDL-cholesterol increased by 11.3% (all P < .001). Mean 10-year ASCVD risk did not change significantly overall (mean relative change, −3.7%; P = .18), but changes differed by TBWL category (analysis of variance, P < .001). Atherosclerotic cardiovascular disease risk decreased among individuals achieving 10% to 20% TBWL (−9.6%; P = .009) and >20% TBWL (−14.2%; P = .005), but not among those achieving <10% TBWL (+7.7%; P = .22). Low-risk prevalence increased from 38.3% to 46.4% (P < .001), with 11.7% transitioning from higher-risk categories to low risk. Main findings: Continuous tirzepatide use for at least 12 months was associated with clinically meaningful improvements in cardiometabolic parameters. Reductions in estimated 10-year ASCVD risk were observed among individuals achieving at least 10% TBWL, supporting greater weight loss as an important marker of cardiovascular risk improvement.


  • Perioperative changes in systemic inflammatory markers predict major complications after distal pancreatectomy

    by Alfredo Verastegui, Sibi Krishna Thiyagarajan, Rachel J. Lew, Mary Tice, John A. Stauffer, Katherine E. Poruk

  • Impact of 24-hour call frequency (every 3rd vs every 4th day) on academic performance of general surgery residents

    by Mauricio Gonzalez-Urquijo, Alfredo Verastegui, Diego Maldonado, Adolfo Leyva-Alvizo, Mario Rodarte-Shade

  • Open Access

    Systemic Inflammatory Indices Predict Survival and Limb Outcomes after Revascularization for Chronic Limb-Threatening Ischemia

    by Franco Imbrognio, Ignacio Pepe, Alfredo Verastegui, Oliver A. Gomez-Gutierrez, Oscar A. De la Torre, Rocio Gau, Diego Herrera-Vegas, Mario Alejandro Fabiani

    Introduction: Chronic limb-threatening ischemia (CLTI) carries high morbidity and mortality, yet risk stratification tools after revascularization remain limited. The Systemic Immune-Inflammation Index (SII) and Systemic Inflammatory Response Index (SIRI) have emerged as prognostic markers. This study evaluated their predictive value in CLTI patients undergoing revascularization. Methods: This retrospective single-center cohort study included 122 CLTI patients undergoing endovascular angioplasty (n = 81) or surgical bypass (n = 41) between 2017 and 2023. Pre-procedural SII and SIRI were calculated from blood counts. Outcomes included: overall survival, major adverse cardiovascular and limb events (MACE/MALE), and limb amputation. Kaplan-Meier analysis, Cox regression with Firth’s penalized likelihood adjustment, and C-index analyses were performed. Results: Surgical bypass was associated with longer median survival than angioplasty (48 vs. 27 months, p = 0.012). Patients in the lowest SII quartile (<492) had significantly improved 84-month survival versus higher quartiles (88.4% vs. 55.1%). Elevated SII remained independently associated with mortality on multivariable analysis. SIRI was higher among patients with adverse events (2.7 vs. 2.0, p = 0.024) but was not independently associated with outcomes. SII demonstrated moderate-to-high predictive performance, with C-indices up to 0.921 in the bypass subgroup. Conclusion: Pre-procedural SII is independently associated with survival following CLTI revascularization and may aid risk stratification.

  • Sex, Not Age, Predicts Weight Loss Outcomes With Tirzepatide: A Retrospective Analysis

    by Regina Castaneda, Dima Bechenati, Rene de J. Rivera Gutierrez, Maria A. Espinosa, Jose Villamarin, Elif Tama, Nancy Safwan, Sima Fansa, Alfredo Verastegui, Allyson W. McNally, et al.

    Objective: This study assessed the impact of sex and age on weight loss outcomes in patients receiving tirzepatide in real‐world clinical practice. Methods: We conducted a retrospective cohort study of adults with overweight or obesity who initiated tirzepatide at Mayo Clinic between June 2022 and May 2024 and completed ≥ 12 months of continuous therapy. Primary outcome was total body weight loss percentage (TBWL%) at 15 months, stratified by sex and age groups (≤ 45, 46–59, ≥ 60 years). Results: Among 1039 patients (57% women; mean age 56 ± 11 years), women achieved significantly greater TBWL% than men after 15 months of treatment (15.1% vs. 10.7%, p < 0.001). Patients aged ≤ 45 years had greater weight loss than those ≥ 60 years (15.1% vs. 12.3%, p = 0.024). In multivariable analyses, greater weight loss was independently associated with female sex, absence of type 2 diabetes, no prior obesity medication use, no concomitant weight gain‐promoting medications, and higher tirzepatide dosage. Age was not an independent predictor. Conclusions: Sex, but not age, predicted weight loss with tirzepatide among individuals using the medication continuously for ≥ 12 months. These findings underscore the importance of incorporating sex‐specific considerations into personalized obesity treatment strategies.


  • Intraoperative radiation therapy during pancreatectomy for borderline and locally advanced pancreatic cancer: A propensity-matched analysis

    by Alfredo Verastegui, Sibi K. Thiyagarajan, Michael Rutenberg, Arielle Jacover, Mary Tice, Daniel M. Koffler, Deepak Shrestha, Byron May, Katherine Poruk, John A. Stauffer

  • Open Access

    Leveraging the Individualized Metabolic Surgery Score to Predict Weight Loss with Tirzepatide in Adults with Type 2 Diabetes and Obesity

    by Regina Castaneda, Diego Sepulveda, Rene Rivera Gutierrez, Jose Villamarin, Dima Bechenati, Maria A. Espinosa, Alfredo Verastegui, Elif Tama, Allyson W. McNally, Pamela K. Bennett, et al.

    Background/Objectives: Individuals with type 2 diabetes (T2D) achieve less total body weight loss (TBWL) with obesity medications compared to those without T2D. The individualized metabolic surgery (IMS) score, originally developed to predict T2D remission after bariatric surgery, inversely correlates with TBWL response to semaglutide. IMS reflects T2D severity, incorporating HbA1c and T2D duration and medication use. This study aims to evaluate TBWL with tirzepatide across IMS severity categories and identify predictors of response in a real-world cohort. Methods: This retrospective analysis included 717 adults with T2D using tirzepatide for overweight or obesity within the Mayo Clinic Health System. Patients were stratified by IMS severity (mild, moderate, severe) and quartiles. Primary endpoint: TBWL% at 15 months. Secondary endpoints: categorical thresholds (≥5%, ≥10%, ≥15%, ≥20%) and predictors of TBWL%. Linear mixed-effects models and regression models were employed. Results: At 15 months, TBWL was greater in mild versus severe IMS groups (14.8% vs. 11.0%, p = 0.015), with similar trends across quartiles. The proportion achieving ≥ 20% TBWL was nearly two-fold higher in mild versus severe IMS (27% vs. 14%, p = 0.03). Female sex independently predicted greater TBWL, whereas insulin use, higher T2D medication burden (particularly weight-promoting agents), and HbA1c > 7% were associated with less TBWL. Conclusions: Tirzepatide produced clinically meaningful TBWL across all IMS categories, although TBWL declined with increasing IMS severity. Glycemic control and T2D medication use emerged as strong predictors of TBWL. The IMS score may serve as a practical tool to anticipate weight-loss trajectories, guide personalized treatment decisions, and inform patient counseling.


  • Comparing guideline adherence and readability: Artificial intelligence with deep learning versus specialized physicians in peripheral artery disease management

    by Alfredo Verastegui, Regina Castaneda, Oliver Antonio Gómez-Gutiérrez, Mauricio Gonzalez-Urquijo, Oscar de la Torre, Diego Herrera Vegas, August Ysa, Manuel García-Toca, Mario Alejandro Fabiani

    Background: Peripheral artery disease (PAD) is a global health challenge. Advances in artificial intelligence (AI), such as large language models (LLMs) and chain-of-thought (CoT) reasoning, offer novel approaches for clinical recommendations. This study compared the readability and guideline adherence of responses from physicians and AI for a standardized PAD case. Methods: This cross-sectional study gathered responses from 30 specialized physicians (11 cardiologists, 19 vascular surgeons) across seven Latin American countries and 13 LLM systems (10 standard, three CoT). Both groups addressed diagnosis, treatment, risks, and prognosis; LLMs responded as vascular specialists. Responses were blindly evaluated with five validated Spanish readability indices and compared to the 2024 ACC/AHA multisocietal PAD guideline. Three experts scored guideline adherence; nonparametric tests were applied. Results: Guideline adherence did not differ significantly between physicians (median 5.8 [3.4–7.6]) and LLMs (7.3 [4.7–9.7], p = 0.169), though CoT-LLMs achieved the highest scores (9.7 [8.5–11.0]). LLMs more often recommended supervised exercise (84.6% vs 30.0%, p = 0.002) and revascularization for quality of life (69.2% vs 20.0%, p = 0.004), whereas physicians favored cilostazol (60.0% vs 30.8%, p = 0.104). LLM responses had lower Readability μ values (46.9 vs 51.4, p = 0.012). Inter-rater reliability was highest for CoT-LLMs (intraclass correlation coefficient [ICC] = 0.98) versus physicians (ICC = 0.76). Conclusion: LLM showed comparable guideline adherence to physicians although CoT models achieved the highest scores. The difference in physician and AI treatment preferences suggest the potential of AI as adjunct clinical tools and warrants further study.


  • Open Access

    Transplant vs. Resection for Non-HCC Malignancies of the Liver

    by Sibi Krishna Thiyagarajan, Arielle Jacover, Alfredo Verastegui, Katherine Poruk, John A. Stauffer

    Background: Surgical resection (SR) and liver transplantation (LT) are the main curative options for non-hepatocellular carcinoma (non-HCC) liver malignancies, including colorectal liver metastases (CRLMs), intrahepatic cholangiocarcinoma (iCCA), hilar cholangiocarcinoma (hCCA), and neuroendocrine tumor liver metastases (NETLMs). Resection aims for negative margins and adequate hepatic reserve, while LT offers treatment for unresectable disease but is limited by donor scarcity, immunosuppression, and ethical constraints. Methods: A targeted literature search (2005–2025) was conducted using PubMed and Google Scholar with predefined MeSH terms combining “liver resection,” “hepatectomy,” and “liver transplantation” across non-HCC malignancies. Relevant studies, reviews, and guidelines were included. Results: For CRLMs, SR remains standard with 5-year overall survival (OS) up to 58%, while LT offers 60–83% in highly selected unresectable cases. In iCCA, resection achieves median survival around 40 months, and LT yields OS up to 69% in very early or neoadjuvant-controlled disease. For hCCA, the Mayo protocol combining neoadjuvant therapy with LT provides 5-year OS of 65–80%. In NETLMs, LT achieves 63–97% OS under strict criteria. Conclusions: SR remains first-line for resectable non-HCC malignancies, while LT provides superior outcomes in unresectable yet biologically favorable disease, emphasizing careful selection and organ allocation.