ECG library
Hypocalcemia: the stretched ST
advancedPerioral tingling and carpopedal spasm two days after a total thyroidectomy.
25 mm/s · 10 mm/mV · synthetic tracing
100%
Calipers:2000 ms50.0 small boxes30 bpm if R-RDrag the orange markers. One small box = 40 ms.
Key findings
- QT prolongation carried by the ST segment, not the T wave
- Post-thyroidectomy timing: the parathyroids are the story
Learning points
- WHERE the QT lengthens localizes the cause: a stretched ST is calcium; a broad, distorted T is more often drugs or congenital.
- The dangerous endpoint of any long QT is the same: torsades. Replace the calcium and check the magnesium that often travels with it.
- Post-thyroidectomy, transfusion (citrate), pancreatitis, and CKD are the ward's usual hypocalcemia stories.
Connected