Symptoms had begun approximately 30 minutes earlier. Complete AV block; bedside ventricular rate approximately 25–30 beats/min. Temperature 36.6°C, GCS 15, SpO2 98% on room air, blood pressure 100/60 mmHg while receiving norepinephrine 0.05 µg/kg/min. No peripheral oedema.
Within the first hour
Temporary transvenous pacemaker inserted; ventricular rate increased to approximately 80 beats/min. Coronary angiography performed; dominant RCA, non-obstructive plaques, no culprit lesion, TIMI 3 flow in all major epicardial vessels.
Approximately 2 hours
Transthoracic echocardiography: LVEF 40–45%, inferior akinesia, moderate mitral regurgitation, mild aortic and tricuspid regurgitation, PASP approximately 25 mmHg, and a newly documented small posterior pericardial effusion (~5 mm) without tamponade.
Following hours
Clinical recovery was incomplete despite pacing. Cold extremities, bilateral 2+ pretibial oedema, pulmonary oedema and progressive renal dysfunction developed.
Approximately 6 hours
Persistent systemic deterioration despite effective pacing and absence of an acute coronary culprit could no longer be explained by the presenting AV block alone; thyroid-function testing was requested as part of a search for an alternative systemic cause.
Later critical deterioration
SpO2 fell into the 30% range. At controlled endotracheal intubation, blood pressure was 90/60 mmHg during norepinephrine infusion at 0.2 µg/kg/min; the temporary pacemaker continued to provide ventricular pacing. Midazolam and rocuronium bromide were administered as part of the intubation regimen. Venous blood during intubation: pH 7.020, pCO2 77.4 mmHg. Cardiac arrest occurred shortly afterwards; return of spontaneous circulation was achieved after approximately 40 minutes of CPR. A second brief cardiac arrest was subsequently resuscitated.
After resuscitation
The previously requested thyroid-function results became available and showed severe primary hypothyroidism (TSH 106 mIU/L, fT3 1.18 pg/mL, fT4 0.38 ng/dL). Integrated with the evolving multisystem dysfunction, myxoedema coma was recognised. Further history disclosed approximately one month of levothyroxine non-adherence. Intravenous hydrocortisone and levothyroxine were initiated.
Final ~6 hours/Days 2–3
Anuria, refractory shock, and progressive multiorgan failure. Temporary pacing continued. Death on hospital day 3.
AV: atrioventricular; CPR: cardiopulmonary resuscitation; fT3: free triiodothyronine; fT4: free thyroxine; GCS: Glasgow Coma Scale; LVEF: left ventricular ejection fraction; PASP: pulmonary artery systolic pressure; pCO2: partial pressure of carbon dioxide; RCA: right coronary artery; SpO2: peripheral oxygen saturation; TIMI: thrombolysis in myocardial infarction; TSH: thyroid-stimulating hormone.
Declarations
Acknowledgments
During the preparation of this work, the authors used ChatGPT (OpenAI) and Antigravity to assist with language refinement and editorial organisation. These tools were not used to make clinical decisions or determine the scientific conclusions. The authors independently reviewed and verified the clinical data, analyses, figure annotations, and references, edited the final text, and take full responsibility for the manuscript.
Author contributions
ABD: Conceptualization, Data curation, Writing—original draft, Writing—review & editing. HG: Data curation, Writing—review & editing. TE: Investigation, Writing—review & editing. SB: Investigation, Writing—review & editing. DK: Supervision, Writing—review & editing. All authors read and approved the submitted version.
Conflicts of interest
The authors declare that they have no conflicts of interest.
Ethical approval
This case report was prepared in accordance with the Declaration of Helsinki. All clinical information was obtained during routine clinical care and was de-identified. Under the institutional policy applicable at Kocaeli City Hospital, formal ethics committee approval is not required for publication of a single anonymised case report.
Consent to participate
As the patient died during the admission, written informed consent to participate was obtained from the patient’s next of kin on his behalf.
Consent to publication
As the patient died during the admission, written informed consent for publication of the anonymised case details and images was obtained from the patient’s next of kin.
Availability of data and materials
The de-identified clinical, laboratory, electrocardiographic and imaging data supporting this case report are available from the corresponding author upon reasonable request, subject to institutional approval and patient-privacy restrictions.
Open Exploration maintains a neutral stance on jurisdictional claims in published institutional affiliations and maps. All opinions expressed in this article are the personal views of the author(s) and do not represent the stance of the editorial team or the publisher.
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