Effects of positive-pressure ventilation, pericardial effusion, and cardiac tamponade on respiratory variation in transmitral flow velocities

Differences between inspiratory and expiratory airway, pleural, and pericardial pressures during each experimental stage. ▵Paw, inspiratory − expiratory airway pressure; ▵Ppl, inspiratory − expiratory pleural pressure; ▵Pper, inspiratory − expiratory pericardial pressure

Respiratory variation in mitral flow velocity and pericardial pressure. Pper ins, inspiratory pericardial pressure, Pper exp = expiratory pericardial pressure. *p < 0.0125 compared with control. As pericardial pressure increases, respiratory variation in transmitral flow decreases.

Patterns of mitral inflow velocity during positive-pressure mechanical ventilation. Insp, onset of inspiration; exp, onset expiration. See text for more detail.