There are no specific ECG findings in patients with chronic pericarditis. T wave inversion may persist. Pericardial effusion dampens the voltage on ECG.
Electrical alternans is observed in the presence of cardiac tamponade due to significant pericardial effusion. However, these findings are obsolete because significant pericardial effusion is detected early.
In patients with constrictive pericarditis, atrial fibrillation and T wave inversion may appear.
Cardiac Tamponade Electrical Alternans 27
27 Burns E, Buttner R. Massive pericardial effusion. Life in the fastlane website. Accessed March 1, 2019.
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