Subarachnoid haemorrhage-induced reversible cardiac dysfunction: time course and potential mechanisms

Area of Science:

• Neuroscience
• Cardiology
• Pharmacology

Background:

• Subarachnoid hemorrhage (SAH) frequently leads to cardiac dysfunction.
• The precise timing and mechanisms of SAH-induced cardiac remodeling are not fully understood.

Purpose of the Study:

• To investigate the temporal profile of cardiac dysfunction following SAH.
• To elucidate the underlying mechanisms, focusing on the neuropeptide Y (NPY) pathway.

Main Methods:

• Utilized a rat model of SAH, assessing cardiac function via hemodynamics and echocardiography at multiple time points.
• Measured plasma biomarkers, NPY levels, and NPY1 receptor expression.
• Administered an NPY1 receptor antagonist in a separate protocol to assess its therapeutic potential.

Main Results:

• SAH induced transient systolic cardiac dysfunction, peaking on Day 3, with elevated heart rate, blood pressure, and catecholamine levels.
• Myocardial injury and inflammation markers correlated with cardiac dysfunction.
• NPY levels and NPY1 receptor expression were altered post-SAH.
• NPY1 receptor antagonism significantly improved cardiac function.

Conclusions:

• SAH triggers acute, transient cardiac dysfunction.
• The NPY-NPY1 receptor pathway, alongside catecholamines, is a key mechanism underlying SAH-induced cardiac dysfunction.