Male implanted with a single-chamber defibrillator (Visia XT VR) for ischaemic cardiomyopathy.
1- What diagnosis is suggested by the interval plot?
The plot shows a probable arrhythmic episode with sudden acceleration into the VT zone; the first 3 bursts and the first 2 ramps do not terminate the arrhythmia; the third ramp accelerates the arrhythmia which remains in the VT zone; a maximum output shock terminates the arrhythmia.
2- What is your final diagnosis?
This is a regular, monomorphic tachycardia with wide QRS complexes on the shock channel compatible with VT; the first 3 bursts (treatment 1) and the first 2 ramps (treatment 2) are ineffective; the third ramp accelerates the arrhythmia without significantly changing the morphology; a shock (treatment 3) terminates the arrhythmia.
