Examples of effusion fluid are pleural effusion and pericardial effusion. Specific examples include subdural, mastoid, pericardial and pleural effusions. Pericarditis can progress to pericardial effusion and eventually cardiac tamponade. During development this space partitions to form the pericardial, pleural and peritoneal cavities. In the 4th week the coelom divides into pericardial, pleural and peritoneal cavities. Correcting the underlying cause such as a tension pneumothorax or pericardial tamponade may help. It consists of fever, pleuritic pain, pericarditis and/or a pericardial effusion. Coxsackie B infection of the heart can lead to pericardial effusion. Correcting the underlying cause such as a pneumothorax or pericardial tamponade, if present, may help. Two died from pericardial tamponade and one was from an aortoduodenal fistula. This is a particularly dangerous eventuality, suggesting that acute pericardial tamponade may be imminent. This pericardial sac is filled with a serous fluid for lubrication. Fluid can build up within the pericardial sack, referred to as a pericardial effusion. It runs through a common pericardial sheath with the pulmonary trunk. It encloses the pericardial cavity which contains pericardial fluid.