In addition, although more rare, some patients might not present until weeks, if not longer, after their infarction with symptoms that prompt the discovery of a chronic PI- VSD. Early PI-VSDs tend to be catastrophic and typically result in early death. The pathophysiology is also variable and complex, but common themes include: 1) worsening cardiac output, often with manifestations of shock and end-organ damage, from acute left ventricular (LV) dysfunction and from increased left-right shunting, 2) acute right ventricular (RV) dysfunction from a sudden increase in pressure, volume, and flow from left to right shunts, and 3) pulmonary.
