Acute brain injury (ABI) affects up to one-third of patients using mechanical circulatory support (MCS). In venoarterial extracorporeal membrane oxygenation (VA ECMO), ABI incidence (11%–40%) has not improved in two decades. Conversely, improvements in left ventricular assist devices (LVADs) have reduced the incidence of stroke, although it remains a major complication (10%–30%). The failure of MCS to ensure adequate cerebral protection may impair cerebrovascular autoregulation (CVAR) and disrupt microcirculatory function affected by reduced pulsatility, endothelial injury, acute perturbations in partial pressure of arterial carbon dioxide (PaCO2), and cerebral venous congestion. Here, we review evidence demonstrating that these factors alter microcirculatory dynamics and CVAR, thereby contributing to ABI through shared mechanistic pathways. Current methods for assessing CVAR are reviewed, including invasive indices such as the pressure reactivity index (PRx) from intracranial pressure monitoring and noninvasive metrics such as the cerebral oximetry index (COx) from near-infrared spectroscopy or flow-velocity correlations from transcranial Doppler. Each method is limited by feasibility, signal artifacts, and inter-modality variability. Our review identifies three priority areas for cerebral protection in MCS: preservation of pulse pressure, cautious titration of PaCO2, and integration of CVAR-informed blood pressure management. Preliminary evidence suggests that very low pulse pressure, rapid carbon dioxide correction, and persistent microcirculatory impairment are each associated with ABI risk. Future investigations should focus on validating bedside tools to assess CVAR and microcirculatory integrity, and on determining whether physiological targets derived from these measures can improve neurological outcomes in patients using MCS.

Many human genetic diseases, including Hutchinson-Gilford progeria syndrome (HGPS), are caused by single point mutations. HGPS is a rare disorder that causes premature aging and is usually caused by a de novo point mutation in the LMNA gene. Base editors (BEs) composed of a cytidine deaminase fused to CRISPR/Cas9 nickase are highly efficient at inducing C to T base conversions in a programmable manner and can be used to generate animal disease models with single amino-acid substitutions. Here, we generated the first HGPS monkey model by delivering a BE mRNA and guide RNA (gRNA) targeting the LMNA gene via microinjection into monkey zygotes. Five out of six newborn monkeys carried the mutation specifically at the target site. HGPS monkeys expressed the toxic form of lamin A, progerin, and recapitulated the typical HGPS phenotypes including growth retardation, bone alterations, and vascular abnormalities. Thus, this monkey model genetically and clinically mimics HGPS in humans, demonstrating that the BE system can efficiently and accurately generate patient-specific disease models in non-human primates.
Animals ; Disease Models, Animal ; Female ; Gene Editing ; Humans ; Lamin Type A/metabolism* ; Macaca fascicularis ; Progeria/pathology*