The correct answer is B, transmutal gradient of the transient outward potassium current across the right ventricle. So let's consider this. The observation is that the ECG shows a coved ST-segment elevation with T-wave inversion in the right pericordial lead. This is a type 1 Brugada pattern ECG. The changes in the ST-segment are the result of differences in the early segment of the action potential of so-called phase 1 across the right ventricular wall. And this is due to differences in the functional expression of the transient outward potassium currents, which are larger in the epicardium than in the endocardium. And although about 20% of patients who have Brugada syndrome have a loss of function mutation in the sodium channel, these do not produce a gradient of this current, neither do calcium channel mutations. And inward rectifier currents govern the resting membrane potential and are much more likely to alter the later phases of the action potential. Let's move on to the next question.

Brugada pattern

ST-segment elevation

potassium currents

sodium channel mutations

action potential