How Much Malperfusion Is Too Much in Acute Type A Aortic Dissections?

Area of Science:

• Cardiovascular Surgery
• Thoracic Surgery
• Vascular Surgery

Background:

• Malperfusion is a critical factor limiting outcomes in acute Type A aortic dissections (AAAD).
• Preoperative metabolic acidosis is a potential marker influencing clinical decision-making in AAAD management.

Purpose of the Study:

• To identify preoperative metabolic acidosis thresholds impacting outcomes in acute Type A aortic dissections (AAAD).
• To evaluate the influence of malperfusion markers and preoperative acidosis on early and long-term survival after AAAD repair.

Main Methods:

• Retrospective review of 153 patients operated on for AAAD between 2002 and 2017.
• Analysis of preoperative variables, including malperfusion markers and pH, using logistic regression and ROC analysis.
• Identification of independent risk factors for early (<30 days) and long-term (>30 days) mortality.

Main Results:

• Pre-bypass pH, entry site, and cardiogenic shock were independent risk factors for early death.
• A pre-bypass pH of 7.25 was identified as a critical threshold for unfavorable early outcomes.
• Patients with pre-bypass pH ≤ 7.25 exhibited a significantly higher relative risk of early mortality (65.7% vs. 22%).

Conclusions:

• A pre-bypass pH ≤ 7.25 is associated with unacceptably high early mortality following AAAD repair.
• This pH threshold may indicate a need for modified treatment strategies, potentially including a two-stage surgical approach.
• Pre-bypass pH and entry site predict early survival, while age predicts long-term survival after AAAD repair.