A New Aortic Arch Dissection Classification: The Fuwai Classification

Early results of frozen elephant trunk in acute type-A dissection in 1445 patients

BACKGROUND

We aimed to briefly describe the use of total arch replacement with frozen elephant trunk in our center's 12-year treatment of acute type A dissection and the early postoperative results. We summarized the practical experience of this procedure in our center and performed regression analyses to find the independent risk factors for major complications.

METHODS

Consecutive patients with acute type A dissection having surgical total arch replacement with the implantation of a frozen elephant trunk were collected from January 2010 to December 2021 and were included in the analysis. For each major operation-related complication, independent risk factors were identified using both univariate and multivariate regression models.

RESULTS

In our institution, the total arch replacement with frozen elephant trunk procedure is used more frequently each year and makes up 70% of the surgical procedures for acute type A dissection. The overall postoperative mortality rate was 6.2%, which declined as the techniques (including surgical procedures, organ perfusion protection etc.) improved. Other complications include: 11.7% for continuous renal replacement therapy, 5.7% for stroke, 17.8% for ICU stay longer than 7 days, 10.9% for prolonged mechanical ventilation, and so on. According to regression analysis, different major complications had different independent risk factors. Several factors, such as advanced age, impaired renal function, and extended cardiopulmonary bypass time, were found to be implicated in nearly all of the complications.

CONCLUSION

Total arch replacement plus frozen elephant trunk strategy is a safe surgical method for extensive acute type A dissection. Some factors, such as advanced age, impaired renal function, and prolonged cardiopulmonary bypass time, might be associated with poor prognosis.

Prediction Nomogram for Postoperative 30-Day Mortality in Acute Type A Aortic Dissection Patients Receiving Total Aortic Arch Replacement With Frozen Elephant Trunk Technique

Objective

To develop and validate a nomogram model to predict postoperative 30-day mortality in acute type A aortic dissection patients receiving total aortic arch replacement with frozen elephant trunk technique.

Method

Clinical data on 1,156 consecutive acute type A aortic dissection patients who got total aortic arch replacement using the frozen elephant trunk technique was collected from January 2010 to December 2020. These patients were divided into training and testing cohorts at random with a ratio of 7:3. To predict postoperative 30-day mortality, a nomogram was established in the training set using the logistic regression model. The novel nomogram was then validated in the testing set. The nomogram's calibration and discrimination were evaluated. In addition, we created four machine learning prediction models in the training set. In terms of calibration and discrimination, the nomogram was compared to these machine learning models in testing set.

Results

Left ventricular end-diastolic diameter <45 mm, estimated glomerular filtration rate <50 ml/min/1.73 m², persistent abdominal pain, radiological celiac trunk malperfusion, concomitant coronary artery bypass grafting and cardiopulmonary bypass time >4 h were independent predictors of the 30-day mortality. The nomogram based on these 6 predictors manifested satisfying calibration and discrimination. In testing set, the nomogram outperformed the other 4 machine learning models.

Conclusion

The novel nomogram is a simple and effective tool to predict 30-day mortality rate for acute type A aortic dissection patients undergoing total aortic arch replacement with frozen elephant trunk technique.

A Novel Sutureless Integrated Stented (SIS) Graft Prosthesis for Type A Aortic Dissection: A Pilot Study for a Prospective, Multicenter Clinical Trial

Aims

Various kinds of surgical strategies and prostheses have been advocated to improve short-term and long-term outcomes in type A aortic dissection (TAAD). Large-scale repair of the pathological aorta is hard to generalize due to complex procedures. We aimed to investigate the performance, effectiveness and safety of a novel Sutureless Integrated Stented (SIS) graft prosthesis in TAAD patients undergoing total arch replacement (TAR) and frozen elephant trunk (FET) implantation surgery.

Methods

All patients admitted to Fuwai Hospital were prospectively screened. Urgent or scheduled surgery was arranged for eligible patients. The primary endpoint was operative mortality. Key secondary endpoints included stroke, spinal cord injury, unexpected aortic reoperation, and 1-year survival. Discharged patients were followed up with computed tomography angiography and transthoracic echocardiography at 3 months, 6 months, and 1 year after surgery. Performance, effectiveness and safety analyses were performed in those patients.

Results

Between August 1 and September 3, 2020, ten TAAD patients were enrolled in this study and successfully implanted with the SIS graft prosthesis. The median (IQR) age was 56.50 (43.75, 66.75) years (range from 31 to 75), and seven patients were male (70.0%). All patients underwent ascending aorta replacement + TAR + FET and additional procedures when necessary. The median (IQR) operation time, cardiopulmonary bypass time and cross clamp time were 270.50 (218.50, 312.50), 110.00 (88.00, 125.75), 69.50 (51.25, 82.75) min, respectively. Of note, the median (IQR) circulatory arrest time was 9.00 (8.00, 9.00) min (range from 4 to 12). The median (IQR) lowest nasopharyngeal temperature was 26.75 (25.98, 27.67) °C. Follow-up was 100% completed. During the 1-year follow-up, no patients died, no severe adverse events occurred, and rate of freedom from aortic reintervention was 100%.

Conclusions

The SIS graft prosthesis was implanted in a novel sutureless way, which simplified the surgical procedure, shortened the circulatory arrest time and avoided deep hypothermia. The preliminary clinical outcomes and follow-up outcomes demonstrated the effectiveness and safety of this prosthesis. A large-scale trial is being conducted to further assess these findings.