This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
Hypercalcaemia in ECG is diagnosed by 
Select and explain. 
A. Increased QT interval, B. Decreased QT interval, C. Increased PR interval, D. Tall T waves
B: Decreased QT interval
Answer: B: Decreased QT interval 
Explanation: Hypocalcemia typically prolongs the QT interval (ST poion), whereas hypercalcemia shoens it .Digitalis glycosides also shoen the QT interval, often with a characteristic "scooping" of the ST-T-wave complex (digitalis effect). Ref Harrison 20th edition pg 1532