Evolution of diagnosis and clinical outcomes in acute aortic dissection: data from the International Registry of Acute Aortic Dissection

Effect of pre-operative hypoxemia on the occurrence and outcomes of post-operative ARDS in Stanford type a aortic dissection patients

BACKGROUND

Pre-operative and post-operative hypoxemia are frequent complications of Stanford type A aortic dissection (AAD). This study explored the effect of pre-operative hypoxemia on the occurrence and outcome of post-operative acute respiratory distress syndrome (ARDS) in AAD.

METHOD

A total of 238 patients who underwent surgical treatment for AAD between 2016 and 2021 were enrolled. Logistic regression analysis was conducted to investigate the effect of pre-operative hypoxemia on post-operative simple hypoxemia and ARDS. Post-operative ARDS patients were divided into pre-operative normal oxygenation group and pre-operative hypoxemia group that were compared for clinical outcomes. Post-operative ARDS patients with pre-operative normal oxygenation were classified as the real ARDS group. Post-operative ARDS patients with pre-operative hypoxemia, post-operative simple hypoxemia, and post-operative normal oxygenation were classified as the non-ARDS group. Outcomes of real ARDS and non-ARDS groups were compared.

RESULT

Logistic regression analysis showed that pre-operative hypoxemia was positively associated with the risk of post-operative simple hypoxemia (odds ratios (OR) = 4.81, 95% confidence interval (CI): 1.67-13.81) and post-operative ARDS (OR = 8.514, 95% CI: 2.64-27.47) after adjusting for the confounders. The post-operative ARDS with pre-operative normal oxygenation group had significantly higher lactate, APACHEII score and longer mechanical ventilation time than the post-operative ARDS with pre-operative hypoxemia group (P < 0.05). Pre-operative the risk of death within 30 days after discharge was slightly higher in ARDS patients with pre-operative normal oxygenation than in ARDS patients with pre-operative hypoxemia, but there was no statistical difference(log-rank test, P = 0.051). The incidence of AKI and cerebral infarction, lactate, APACHEII score, mechanical ventilation time, intensive care unit and post-operative hospital stay, and mortality with 30 days after discharge were significantly higher in the real ARDS group than in the non-ARDS group (P < 0.05). After adjusting for confounding factors in the Cox survival analysis, the risk of death within 30 days after discharge was significantly higher in the real ARDS group than in the non-ARDS group (hazard ratio(HR): 4.633, 95% CI: 1.012-21.202, P < 0.05).

CONCLUSION

Preoperative hypoxemia is an independent risk factor for post-operative simple hypoxemia and ARDS. Post-operative ARDS with pre-operative normal oxygenation was the real ARDS, which was more severe and associated with a higher risk of death after surgery.

Incidental Finding of Thoracic Aortic Dissection in a Patient Post-Coronary Artery Bypass Graft Surgery

Thoracic aortic dissection (TAD) is an uncommon but potentially fatal complication of coronary artery bypass graft (CABG). Most patients present to the emergency room with severe chest pain, shortness of breath, or after a syncopal episode. Asymptomatic patients pose a challenge to diagnosis. The authors present a case of an 82-year-old male, who was found to have an incidental finding of a 5-cm ascending aortic aneurysm with an intimal dissection flap four months after CABG. Extensive workup on possible risk factors such as underlying aortic diseases, genetic conditions, and hypertensive crisis proved noncontributory. Aggressive blood pressure control was achieved, and the patient was observed in the intensive care unit before discharge with follow-up. The purpose of this case report is to alert clinicians of TAD after CABG and highlight the importance of developing a protocol for follow-up and monitoring of patients who have undergone CABG, as complications can be asymptomatic. Early and accurate diagnosis of TAD as a complication of CABG is essential to improving survival rates.

Early and Late Mortality Predictors in Patients with Acute Aortic Dissection Type B

BACKGROUND/AIM

Despite technological advances in diagnosis and treatment, in-hospital mortality with acute aortic dissection type B is still about 11%. The purpose of this study was to assess the risk factors for early and long-term adverse outcomes in patients with acute aortic dissection type B treated medically or with conventional open surgery.

METHODS

The present study included 104 consecutive patients with acute aortic dissection type B treated in our Center from January 1st, 1998 to January 1st, 2007. Patient demographic and clinical characteristics as well as in-hospital complications were reviewed. Univariate and multivariate testing was performed to identify the predictors of in-hospital (30-day) and late (within 9 years) mortality.

RESULTS

92 (88.5%) patients were treated medically, while 12 (11.5%) patients with complicated acute aortic dissection type B were treated by open surgical repair. In-hospital complications occurred in 35.7% patients, the most often being acute renal failure (28%), hypotension/shock (24%), mesenteric ischemia (12%), and limb ischemia (8%). The in-hospital mortality rate was 15.7% and the 9-year mortality rate was 51.9%. Independent predictors of early mortality in patients with acute aortic dissection type B were uncontrolled hypertension (HR-20.69) and a dissecting aorta diameter >4.75 cm (HR-6.30). Independent predictors of late mortality were relapsing pain (HR-7.93), uncontrolled hypertension (HR-7.25), and a pathologic difference in arterial blood pressure (>20 mmHg) (HR-5.33).

CONCLUSION

Knowledge of key risk factors may help with a better choice of treatment and mortality reduction in acute aortic dissection type B patients.

Factors Affecting Outcomes in Acute Type A Aortic Dissection: A Systematic Review

Acute type A aortic dissection is a clinical emergency and is associated with significant morbidity and mortality rates if not managed promptly in specialised and high-volume centres. The mortality rate is increased by 1% for each hour delay in management; however, with advancement in clinical practice, diagnostic imaging and clinician awareness, this has been dramatically reduced to below 30% in most international centres. Not only timing of recognition of the pathology, but also other factors can significantly affect outcomes of such critical pathology. This includes, but is not limited to, age, extent of the pathology, existence of connective tissue disorders, hypertension, diabetes mellitus and surgeon experience. This narrative review will focus on current clinical practice and the evidence behind optimising each factor to minimise adverse outcomes in such high-risk cohort.

Oxygenation impairment after total arch replacement with a stented elephant trunk for type-A dissection

OBJECTIVE

To study the risk factors of oxygenation impairment in patients with type-A acute aortic dissection who underwent total arch replacement with a stented elephant trunk.

METHODS

In this study, 169 consecutive patients were enrolled who were diagnosed with type-A acute aortic dissection and underwent a total arch replacement procedure at the Qilu Hospital of Shandong University between January 2015 and February 2017. Postoperative oxygenation impairment was defined as arterial oxygen partial pressure/inspired oxygen fraction ≤ 200 with positive end expiratory pressure ≥ 5 cm H₂O that occurred within 72 hours of surgery. Perioperative clinical characteristics of all patients were collected and univariable analyses were performed. Risk factors associated with oxygenation impairment identified by univariable analyses were included in the multivariable regression analysis.

RESULTS

The incidence of postoperative oxygenation impairment was 48.5%. Postoperative oxygenation impairment was associated with prolonged mechanical ventilation time, intensive care unit stay, and hospital stay. Multivariable regression analysis demonstrated that body mass index (odds ratio [OR], 1.204; 95% confidence interval [CI], 1.065-1.361; P = .003), preoperative oxygenation impairment (OR, 9.768; 95% CI, 4.159-22.941; P < .001), preoperative homocysteine (OR, 1.080; 95% CI, 1.006-1.158; P = .032), circulatory arrest time (OR, 1.123; 95% CI, 1.044-1.207; P = .002), and plasma transfusion (OR, 1.002; 95% CI, 1.001-1.003; P = .002) were significantly associated with postoperative oxygenation impairment.

CONCLUSIONS

Postoperative oxygenation impairment is a common complication of surgery for type-A acute aortic dissection. Body mass index, preoperative oxygenation impairment, preoperative homocysteine, circulatory arrest time, and plasma transfusion were independent risk factors for oxygenation impairment after a total arch replacement procedure.