Centrifuge-Simulated Spaceflight After Aortic Valve Replacement and Atrial Septal Defect Repair

Area of Science:

• Cardiovascular Physiology
• Space Medicine
• Human Factors in Aerospace

Background:

• Commercial spaceflight is expanding, increasing the number of spaceflight participants (SFPs) with diverse medical histories.
• SFPs may present unique risks due to pre-existing conditions and less rigorous screening compared to career astronauts.
• Postcardiothoracic surgery risks for SFPs are largely unstudied, particularly within one year of surgery.

Observation:

• A 40-year-old male, 8 months post-aortic valve replacement and atrial septal defect repair, participated in centrifuge-simulated spaceflight.
• The subject endured simulated orbital and suborbital flight profiles, including +4.0 Gz and +4.5 Gx.
• Physiological data and questionnaires monitored the subject's response to hypergravity exposure.

Findings:

• The subject tolerated the hypergravity exposures well from a physiological standpoint.
• Progressive sternal pain increased with higher +Gx forces, leading the subject to withdraw from the final profile.
• This indicates potential challenges for post-cardiac surgery patients in high-G environments.

Implications:

• This case demonstrates a method for risk stratification and medical management of post-surgical SFPs.
• Preparticipation evaluation and ongoing monitoring are crucial for individuals with significant cardiac history.
• Further research is needed to understand and mitigate risks for SFPs with recent thoracic surgery.