Beyond the Mehran Risk Score: Predictive Value of Total Ischemic Time for Contrast-Induced Nephropathy in ST Segment Elevation Myocardial Infarction Patients Undergoing Primary Percutaneous Coronary Intervention.

September 12, 2026 updated by: Asmaa talaat, Assiut University

Contrast-Induced Nephropathy (CIN) is a serious complication following primary percutaneous coronary intervention (PCI) in patients presenting with acute ST-segment elevation myocardial infarction (STEMI). While the standard Mehran Risk Score uses static baseline clinical and procedural variables, it lacks dynamic parameters reflecting acute myocardial ischemic duration. Total ischemic time-from symptom onset to balloon inflation-drives systemic inflammation, forward cardiac failure, and renal hypoperfusion.

This prospective observational validation cohort study aims to evaluate the independent predictive value of Total Ischemic Time for CIN in acute STEMI patients undergoing primary PCI. Additionally, it investigates whether integrating total ischemic duration into the classic Mehran Risk Score enhances discrimination accuracy, net reclassification, and calibration performance for early pre-procedural risk stratification.

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Detailed Description

Background:

Contrast-Induced Nephropathy (CIN) remains one of the most significant complications following primary percutaneous coronary intervention (PPCI) in patients presenting with ST-segment elevation myocardial infarction (STEMI). The traditional Mehran Risk Score utilizes static baseline parameters (such as hypotension, IABP, CHF, age, anemia, diabetes, contrast volume, and baseline eGFR) to stratify CIN risk. However, it omits the duration of acute myocardial ischemia. Prolonged total ischemic time (the interval from symptom onset to first balloon inflation/device placement) triggers severe systemic inflammatory cascades, hemodynamic instability, and transient renal hypoperfusion, which may independently increase susceptibility to contrast-induced acute kidney injury.

Objectives:

To evaluate the independent predictive value of Total Ischemic Time for Contrast-Induced Nephropathy (CIN) in acute STEMI patients undergoing primary PCI.

To investigate whether integrating total ischemic duration into the classic Mehran Risk Score enhances its predictive performance, discrimination, calibration, and risk reclassification capacity.

Methods & Procedure:

This prospective observational validation cohort study will recruit consecutive adult STEMI patients presenting to Assiut University Heart Hospital undergoing primary PCI within 12 hours of symptom onset. Total ischemic time (symptom-to-balloon time) will be precisely documented upon presentation. Baseline laboratory tests including serum creatinine, blood urea nitrogen (BUN), complete blood count (CBC), and blood glucose will be drawn prior to PCI. Serum creatinine will be re-evaluated at 24, 48, and 72 hours post-PCI to detect CIN (defined as an absolute increase in serum creatinine of ≥ 0.5 mg/dL or a relative increase of ≥ 25% from baseline within 48-72 hours post-contrast administration).

Statistical modeling will compare the performance of the classic Mehran Risk Score against a modified model incorporating total ischemic time using Area Under the Receiver Operating Characteristic Curve (AUROC), Net Reclassification Improvement (NRI), and Integrated Discrimination Improvement (IDI).

Study Type

Observational

Enrollment (Estimated)

400

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

  • Name: Hamdy Shams Eldin Mohamed, Professor of Cardiology
  • Phone Number: +201065601161
  • Email: hamdyshams@aun.edu.eg

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

Yes

Sampling Method

Non-Probability Sample

Study Population

Consecutive adult patients aged >=18 years presenting with acute ST-segment elevation myocardial infarction (STEMI) within 12 hours of symptom onset who undergo emergency primary percutaneous coronary intervention (PPCI) at Assiut University Heart Hospital.

Description

Inclusion Criteria:

  • Inclusion Criteria:

    1. Patients aged >=18 years at the time of presentation.
    2. Definitive diagnosis of acute ST-segment elevation myocardial infarction (STEMI) presenting within 12 hours of symptom onset, characterized by typical ischemic symptoms (e.g., retrosternal chest pain) and electrocardiographic criteria: persistent ST-segment elevation >=1 mm in >=2 contiguous limb leads, or >=2 mm in >=2 contiguous precordial leads (V2-V3 thresholds: >=2.5 mm in men <40 years, >=2.0 mm in men >=40 years, and >=1.5 mm in women), or a validated new or presumably new left bundle branch block (LBBB).
    3. Selection for immediate mechanical reperfusion via emergency primary percutaneous coronary intervention (PPCI) according to current guidelines.
    4. A reliable and verifiable chronological timeline regarding the exact onset of chest pain or ischemic symptoms to ensure precise calculation of the total ischemic duration.

    5. Willingness to participate, demonstrated by signed, informed consent obtained from the patient or an authorized family representative prior to data collection under approved institutional protocols.

      .

      Exclusion Criteria:

    1. Pre-existing end-stage renal disease (ESRD) requiring long-term peritoneal dialysis or hemodialysis, or an admission baseline eGFR <15 mL/min/1.73m2.
    2. Prior exposure to iodinated contrast media within the past 7 days, or scheduled elective contrast procedures within the subsequent 72 hours.
    3. Intentional pre-procedural administration of structured, high-volume intravenous fluid hydration regimens specifically designed to prevent contrast nephropathy (e.g., sodium bicarbonate protocols), which would confound baseline renal kinetics.
    4. Known active treatment with high-potency nephrotoxic drugs within the 48 hours prior to admission (e.g., cisplatin, high-dose aminoglycosides, amphotericin B).
    5. Active pregnancy, ongoing breastfeeding, or severe non-cardiac co-morbidities associated with a life expectancy <30 days (e.g., advanced terminal malignancies)

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
Intervention / Treatment
STEMI Patients Undergoing Primary PCI
Consecutive adult STEMI patients presenting within 12 hours of symptom onset who undergo primary percutaneous coronary intervention (PPCI). Total ischemic time and baseline serum creatinine are measured, and renal function is monitored at 24, 48, and 72 hours post-PCI to evaluate Contrast-Induced Nephropathy (CIN).
Diagnostic test: Total Ischemic Time Evaluation
Measurement and documentation of the time duration from symptom onset to primary PCI balloon inflation/device placement.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Incidence of Contrast-Induced Nephropathy (CIN)
Time Frame: Up to 72 hours post-procedure
Incidence of CIN, defined as an absolute increase in serum creatinine of ≥ 0.5 mg/dL or a relative increase of ≥ 25% from baseline values measured at 24, 48, and 72 hours following primary PCI.
Up to 72 hours post-procedure

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Serial Variations of Renal Biomarkers and Short-Term Clinical Outcomes
Time Frame: Baseline, 24, 48, and 72 hours post-procedure, up to index hospital discharge (up to 7 days)
Tracking serial chronological variations of renal biomarker metrics including serum creatinine, blood urea nitrogen (BUN), and estimated glomerular filtration rate (eGFR) calculated via CKD-EPI 2021 equation, alongside the incidence of major adverse cardiovascular events (MACE), emergent renal replacement therapy, and short-term in-hospital mortality across total ischemic time sub-cohorts.
Baseline, 24, 48, and 72 hours post-procedure, up to index hospital discharge (up to 7 days)

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Assiut University

Investigators

  • Principal Investigator: Hamdy Shams Eldin Mohamed, Professor of Cardiology, Cardiology Department, Faculty of Medicine, Assiut University

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

October 1, 2026

Primary Completion (Estimated)

July 15, 2028

Study Completion (Estimated)

August 25, 2028

Study Registration Dates

First Submitted

September 12, 2026

First Submitted That Met QC Criteria

September 12, 2026

First Posted (Actual)

September 17, 2026

Study Record Updates

Last Update Posted (Actual)

September 17, 2026

Last Update Submitted That Met QC Criteria

September 12, 2026

Last Verified

July 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • total ischemic time CIN

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

Individual participant data will not be shared to protect patient privacy and maintain strict confidentiality in accordance with the study protocol and institutional review board guidelines. Only aggregated study results will be made available upon publication.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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