BEUDAMED
    FDA Adverse Event Injury Summary report: N

    DOWNSTREAM SYSTEM

    MDR report key: 24475098 · Received February 27, 2026

    Report

    Report Number
    2030964-2026-00001
    Event Type
    Injury
    Date Received
    February 27, 2026
    Date of Event
    December 16, 2025
    Report Date
    February 27, 2026
    Manufacturer
    THEROX INC
    Product Code
    MWG
    Adverse Event
    Yes
    Report Source
    Manufacturer report
    Reporter Location
    NJ, US
    Reporter Occupation
    OTHER HEALTH CARE PROFESSIONAL
    Health Professional
    Yes

    Narratives

    Additional Manufacturer Narrative · 0

    FOR G4: PMA/510(K): PREMARKET SUBMISSION NUMBER NOT AVAILABLE/NOT RELEASED. THE THEROX DOWNSTREAM CONSOLE INVOLVED IN THE CUSTOMER'S REPORTED COMPLAINT WAS NOT RETURNED TO ZOLL FOR INVESTIGATION BECAUSE NO MALFUNCTION OCCURRED. THE CONSOLE LOG DATA WAS REVIEWED, AND BASED ON IT, THERE WERE NO ISSUES WITH DEVICE OPERATION. A 60-MINUTE SSO2 THERAPY WAS PERFORMED SUCCESSFULLY. SUPERSATURATED OXYGEN (SSO2) THERAPY IS AN ADJUNCTIVE CARDIAC CATHETERIZATION LABORATORY-INITIATED PROCEDURE TARGETED AT THE LEFT MAIN CORONARY ARTERY (LMCA) OF AN ACUTE MYOCARDIAL INFARCTION (AMI) PATIENT AFTER SUCCESSFUL PERCUTANEOUS INTERVENTION (PCI) WITH STENTING HAS BEEN PERFORMED OF THE LEFT ANTERIOR DESCENDING CORONARY ARTERY. THE THEROX DOWNSTREAM SYSTEM IS INDICATED FOR THE PREPARATION AND DELIVERY OF SUPERSATURATED OXYGEN THERAPY (SSO2 THERAPY) TO TARGETED ISCHEMIC REGIONS PERFUSED BY THE PATIENT'S LEFT ANTERIOR DESCENDING CORONARY ARTERY IMMEDIATELY FOLLOWING REVASCULARIZATION BY MEANS OF PERCUTANEOUS CORONARY INTERVENTION (PCI) WITH STENTING THAT HAS BEEN COMPLETED WITHIN 6 HOURS AFTER THE ONSET OF ANTERIOR ACUTE MYOCARDIAL INFARCTION (AMI) SYMPTOMS CAUSED BY A LEFT ANTERIOR DESCENDING ARTERY INFARCT LESION. EVENT OF STENT THROMBOSIS WAS SERIOUS AS EVENT REQUIRED ADDITIONAL INTERVENTION AND WAS MORE LIKELY RELATED TO THE PATIENT CLINICAL CONDITION. AT THE SAME TIME, BASED ON ALL AVAILABLE INFORMATION AND MEDDEV DEFINITIONS, EVENT OF STENT THROMBOSIS WAS ASSESSED AS POSSIBLE RELATED TO THEROX DEVICE AND SSO2 PROCEDURE WITH THIS DEVICE. EVENT OF DEATH WAS SERIOUS AND WAS MORE LIKELY RELATED TO THE PATIENT CLINICAL CONDITION. EVENT WAS UNLIKELY RELATED TO THE THEROX DOWNSTREAM SYSTEM BECAUSE CARDIAC ARREST WHEN THE PATIENT WAS UNABLE TO BE RESUSCITATED OCCURRED 8 DAYS POST-PROCEDURE.

    Description of Event or Problem · 0

    A 47 Y/O SPANISH-SPEAKING MALE FROM GUATEMALA PRESENTS TO THE ED AT 7:34 A.M. WITH 10/10 CHEST PAIN, NAUSEA, AND DIAPHORESIS, WHICH BEGAN AT 6 A.M. IN THE MORNING. PATIENT HAS A HISTORY OF HTN AND LEFT LEG DVT (DEEP VEIN THROMBOSIS) FOR WHICH HE TAKES AN UNKNOWN ANTICOAGULANT (LATER DOCUMENTED AS XARELTO) THAT WAS GIVEN TO HIM BY A DOCTOR IN GUATEMALA. THE LAST DOSE WAS AT 4 P.M. THE DAY BEFORE ADMISSION. INITIAL EKG IN THE ED WAS WITHOUT EVIDENCE OF ACUTE MYOCARDIAL INFARCTION. SUBSEQUENT ED EKG SHOWED ANTEROLATERAL ST ELEVATIONS WITH RECIPROCAL ST DEPRESSIONS. ASPIRIN 324 MG PO, TICAGRELOR 180 MG PO, ATORVASTATIN 80 MG PO WERE GIVEN, AND THE PATIENT WAS TAKEN EMERGENTLY TO THE CATH LAB. CARDIAC CATH WAS PERFORMED WHICH SHOWED A 50% LEFT MAIN LESION, 100% OSTIAL TO MID LAD LESION, 100% RCA CTO WITH R- >R COLLATERALS, 80% CIRCUMFLEX LESION. LVEF (LEFT VENTRICULAR EJECTION FRACTION) WAS 20-25%. PCI OF THE LAD WAS INITIATED WITH HEPARIN ALONE, WITHOUT GPIIB/IIIA, FOR ANTICOAGULATION. UPON CROSSING THE LESION WITH AN INTERVENTIONAL GUIDEWIRE, THE MONITOR SHOWED VENTRICULAR FIBRILLATION, AND THE PATIENT WAS DEFIBRILLATED TO NSR. THE PATIENT WAS SUBSEQUENTLY INTUBATED, AND STENT PLACEMENT FOLLOWED BY THROMBECTOMY WAS SUCCESSFULLY PERFORMED IN THE LAD. NEXT, THE PATIENT RECEIVED THEROX SUPER-SATURATED OXYGEN THERAPY FOR 60 MINUTES. ACT (ACTIVATED CLOTTING TIME) RESULT JUST PRIOR TO INITIATING THEROX WAS 286 SECONDS, AND A HEPARIN 1000-UNIT BOLUS WAS GIVEN. TWENTY MINUTES AFTER INITIATION, THE ACT RESULT WAS 241 SECONDS, AND A HEPARIN BOLUS OF 4000 UNITS WAS GIVEN. THE SUBSEQUENT ACT RESULTS BEFORE STOPPING THEROX WERE 336 AND 303 SECONDS. IMMEDIATELY AFTER SUPER-SATURATED OXYGEN THERAPY, ANGIOGRAPHY REVEALED AN OCCLUDED LAD AND THROMBUS IN THE DISTAL CIRCUMFLEX AND LEFT MAIN. ACT MEASURED 241 SECONDS, 12 MINUTES POST STOPPAGE. EPTIFIBATIDE BOLUS X2 AND IV DRIP WERE STARTED, AND IMPELLA WAS INSERTED. THROMBECTOMY AND POBA (PLAIN OLD BALLOON ANGIOPLASTY) IN THE LAD WERE THEN PERFORMED, AND A STENT WAS PLACED IN THE PROXIMAL CIRCUMFLEX ARTERY SUCCESSFULLY. POST-PROCEDURE, THE PATIENT REQUIRED 15 DAYS OF TREATMENT IN THE CRITICAL CARE UNIT AND WAS THEN DOWNGRADED TO TELEMETRY. THE PATIENT REMAINED ON TELEMETRY FOR 8 DAYS, AND DISCHARGE WAS ANTICIPATED; HOWEVER, THE PATIENT SUFFERED CARDIAC ARREST AND WAS UNABLE TO BE RESUSCITATED.

    Devices

    Seq Brand Generic Product Code Manufacturer Model Lot UDI-DI
    532548 DOWNSTREAM SYSTEM SUPERSATURATED OXYGEN THERAPY SYSTEM MWG THEROX INC DS-2

    Patients

    Seq Age Sex Outcome Treatment
    1