Organ-specific malperfusion in acute type A aortic dissection: epidemiological meta-analysis of incidence rates.

Background: Acute type A aortic dissection is a life-threatening clinical emergency that necessitates immediate surgical intervention with an estimated mortality rate of approximately 1-2% per hour. When complicated by malperfusion, the perioperative mortality rate is reported to be increased by up to 39%. Malperfusion can affect many vascular beds with varying incidence and severity, resulting in coronary, cerebral, visceral, peripheral, renal or spinal malperfusion. The primary aim of this systematic review and meta-analysis is to investigate the epidemiology of specific types of organ malperfusion in acute type A aortic dissection and to analyse the impact on the survival outcomes associated with each malperfusion type.

Methods: Electronic databases PubMed, MEDLINE and Embase were searched through to September 2024 to identify original studies that presented data on the incidence and the survival outcome of organ malperfusion in association with acute type A aortic dissection. The extracted data included patient characteristics and incidence of organ-specific malperfusion. Primary outcomes were the respective in-hospital mortality rate associated with each organ-specific malperfusion and a proportional meta-analysis was conducted to pool results. Quality assessment was performed using the modified National Institutes of Health quality assessment tool for single-arm observational studies.

Results: A total of 40 studies met the inclusion criteria, including a total of 35 361 patients. Peripheral limb malperfusion was the most prevalent with a pooled incidence of 12% (95% c.i. 10 to 14). This was followed by lower limb or iliofemoral with 11% (95% c.i. 9 to 14). Spinal malperfusion was the lowest with 1% (95% c.i. 1 to 2). The pooled mortality rate with organ malperfusion varied between 18 and 36%. Within this population the highest mortality rate was associated with mesenteric malperfusion with 36% (95% c.i. 28 to 45). Following this the highest mortality rate was found with coronary at 33% (95% c.i. 26 to 40) and cerebral at 28% (95% c.i. 24 to 33) malperfusion.

Conclusion: Survival during hospital admission after acute type A aortic dissection can vary depending on the presence and type of malperfusion, with mesenteric, coronary and cerebral malperfusion being associated with the highest in-hospital mortality rates. Organ-specific malperfusion syndromes should be considered when assessing the perioperative risk and surgical planning of patients undergoing surgical repair for acute type A aortic dissection.