Every year, around 50,000 people in the United States experience cardiogenic shock — a life-threatening condition, usually caused by a severe heart attack, in which the heart can’t pump enough blood for the body’s needs.

Many of these patients end up receiving help from a mechanical pump that can temporarily help the heart pump blood until it recovers enough to function on its own. However, in nearly half of these patients, the extra help leads to an imbalance between the left and right ventricles, which can pose danger to the patient.

In a new study, MIT researchers have discovered why that imbalance occurs, and identified factors that make it more likely. They also developed a test that doctors could use to determine whether this dysfunction will occur in a particular patient, which could give doctors more confidence when deciding whether to use these pumps, known as ventricular assist devices (VADs).

“As we improve the mechanistic understanding of how these technologies interact with the native physiology, we can improve device utility. And if we have more algorithms and metrics-based guidance, that will ease use for clinicians. This will both improve outcomes across these patients and increase use of these devices more broadly,” says Kimberly Lamberti, an MIT graduate student and the lead author of the study.