A patient presents with low grade fever, his ECG is as shown below. What is the most probable diagnosis?

The electrocardiogram (ECG) is very useful in the diagnosis of acute pericarditis. Characteristic manifestations of acute pericarditis on ECG most commonly include diffuse ST-segment elevation. However, other conditions may have ECG features similar to those of acute pericarditis. Pericarditis is inflammation of the pericardium (the fibrous sac surrounding the hea).Symptoms typically include sudden onset of sharp chest pain.The pain may also be felt in the shoulders, neck, or back. It is typically better sitting up and worse when lying down or breathing deeply.Other symptoms may include fever, weakness, palpitations, and shoness of breath. Occasionally onset of symptoms is gradual. Substernal or left precordial pleuritic chest pain with radiation to the trapezius ridge (the bottom poion of scapula on the back) is the characteristic pain of pericarditis. The pain is usually relieved by sitting up or bending forward, and worsened by lying down (both recumbent and supine positions) or by inspiration (taking a breath in). The pain may resemble that of angina but differs in that pericarditis pain changes with body position, where hea attack pain is generally constant and pressure-like. Other symptoms of pericarditis may include dry cough, fever, fatigue, and anxiety. Due to its similarity to the pain of myocardial infarction (hea attack), pericarditis can be misdiagnosed as a hea attack. Acute myocardial infarction can also cause pericarditis, but the presenting symptoms often differ enough to warrant diagnosis. Ref Harrison20th edition pg 2776