Extent of preoperative false lumen thrombosis does not influence long-term survival in patients with acute type A aortic dissection

Twenty-five years of observations from the International Registry of Acute Aortic Dissection (IRAD) and its impact on the cardiovascular scientific community

OBJECTIVE

The International Registry of Acute Aortic Dissection (IRAD) celebrated its 25th anniversary in January 2021. This study evaluated IRAD's role in promoting the understanding and management of acute aortic dissection (AD) over these years.

METHODS

IRAD studies were identified, analyzed, and ranked according to their citations per year (c/y) to determine the most-cited IRAD studies and topics. A systematic search of the literature identified cardiovascular guidelines on the diagnosis and management of acute AD. Consequently, IRAD's presence and impact were quantified using these documents.

RESULTS

Ninety-seven IRAD studies were identified, of which 82 obtained more than 10 cumulative citations. The median c/y index was 7.33 (25th-75th percentile, 4.01-16.65). Forty-two studies had a greater than median c/y index and were considered most impactful. Of these studies, most investigated both type A and type B AD (n = 17, 40.5%) and short-term outcomes (n = 26, 61.9%). Nineteen guideline documents were identified from 26 cardiovascular societies located in Northern America, Europe, and Japan. Sixty-nine IRAD studies were cited by these guidelines, including 38 of the 42 most-impactful IRAD studies. Among them, partial thrombosis of the false lumen as a predictor of postdischarge mortality and aortic diameters as a predictor of type A occurrence were determined as most-impactful specific IRAD topics by their c/y index.

CONCLUSIONS

IRAD has had and continues to have an important role in providing observations, credible knowledge, and research questions to improve the outcomes of patients with acute AD.

Preoperative Predictors of Late Aortic Expansion in Acute Type B Aortic Dissection Treated with TEVAR

BACKGROUND

A patent false lumen (FL) in patients with thoracic endovascular aortic repair (TEVAR)-treated type B aortic dissection (TBAD) can cause a significant risk for late aortic expansion (LAE). We hypothesize that preoperative features can predict the occurrence of LAE.

METHODS

Sufficient preoperative and postoperative follow-up clinical and imaging feature data for patients treated with TEVAR in the First Affiliated Hospital of Nanjing Medical University from January 2018 to December 2020 were collected. A univariate analysis and multivariable logistic regression analysis were used to find potential risk factors of LAE.

RESULTS

Ninety-six patients were finally included in this study. The mean age was 54.5 ± 11.7 years and 85 (88.5%) were male. LAE occurred in 15 (15.6%) of 96 patients after TEVAR. Two preoperative factors showed strong associations with LAE according to the multivariable logistic regression analysis: preoperative partial thrombosis of the FL (OR = 10.989 [2.295-48.403]; p = 0.002) and the maximum descending aortic diameter (OR = 1.385 [1.100-1.743] per mm increase; p = 0.006).

CONCLUSIONS

Preoperative partial thrombosis of the FL and an increase in the maximum aortic diameter are strongly associated with late aortic expansion. Additional interventions of the FL may help to improve the prognosis of patients with the high risk of late aortic expansion.

Effect of Aortic Valve Type on Patients Who Undergo Type A Aortic Dissection Repair

Aortic valve replacement (AVR) is common in the setting of type A aortic dissection (TAAD) repair. Here, we evaluated the association between prosthesis choice and patient outcomes in an international patient cohort. We reviewed data from the International Registry of Acute Aortic Dissection (IRAD) interventional cohort to examine the relationship between valve choice and short- and mid-term patient outcomes. Between January 1996 and March 2016, 1290 surgically treated patients with TAAD were entered into the IRAD interventional cohort. Of those, 364 patients undergoing TAAD repair underwent aortic valve replacement (AVR; mean age, 57 years). The mechanical valve cohort consisted of 189 patients, of which 151 (79.9%) had a root replacement. The nonmechanical valve cohort consisted of 5 patients who received homografts and 160 patients who received a biologic AVR, with a total of 118 (71.5%) patients who underwent root replacements. The mean follow-up time was 2.92 ± 1.75 years overall (2.46 ± 1.69 years for the mechanical valve cohort and 3.48 ± 1.8 years for the nonmechanical valve cohort). After propensity matching, Kaplan-Meier estimates of 4-year survival rates after surgery were 64.8% in the mechanical valve group compared with 74.7% in the nonmechanical valve group (p = 0.921). A stratified Cox model for 4-year mortality showed no difference in hazard between valve types after adjusting for the propensity score (p = 0.854). A biologic valve is a reasonable option in patients with TAAD who require AVR. Although this option avoids the potential risks of anticoagulation, long-term follow up is necessary to assess the effect of reoperations or transcatheter interventions for structural valve degeneration.

Repair of Acute Type-A Aortic Dissection in the Present Era: Outcomes and Controversies

Acute Type-A aortic dissection (AAAD) remains a surgical emergency with a relatively high operative mortality despite advances in medical and surgical management over the past three decades. In spite of the severity of disease, there is a paucity of studies reviewing key controversies surrounding AAAD repair and management. A systematic literature search was performed using Cochrane review and PubMed bibliography review. Abstracts were first reviewed for general pertinence and then articles were reviewed in full. Literature review indicates that use of moderate hypothermia and antegrade cerebral perfusion is a safe alternative to deep hypothermia. In hemodynamically stable patients, axillary cannulation may be substituted for femoral cannulation. With regard to the technical aspects of repair, preserving the aortic root whenever possible and performing the distal anastomosis with the open distal technique rather than with the clamp on is the preferred approach. In patients with a patent false lumen, close monitoring is indicated. As demonstrated by the literature, significant improvement of early and late mortality over the past years has occurred in patients presenting with AAAD. Repair of acute Type-A aortic dissection remains a challenge with high operative mortality; however, improvement of surgical techniques and management have resulted in improvement of early and late clinical outcomes.

Aortic morphology post type A acute aortic syndrome: Prognosis significance and association with 24-hour blood pressure-monitoring parameters

BACKGROUND

After an emergent surgery for type A acute aortic syndrome, medical management is based on optimal blood pressure (BP) control. We assessed the prognostic significance of BP monitoring and its relationship with aortic morphology following type A acute aortic syndrome.

METHODS

The data of 120 patients who underwent BP monitoring after a type A acute aortic syndrome from January 2005 to June 2016 were retrospectively collected. The first CT angiogram performed after surgery was used for the morphological analysis.

RESULTS

The population included 79 males, with an overall mean age of 60 ± 12 years. Seven patients (5.8%) died during a median follow-up of 5.5 years. The median delay between BP monitoring and discharge was 3 (1-5) months. The mean 24-hour BP of the cohort was 127/73 mm Hg ± 10/17. During follow-up, different parameters of BP monitoring were not associated with the risk of aortic events. However, the diameter of the false lumen of the descending thoracic aorta was the best predictor associated with the risk of new aortic events during follow-up, particularly for the threshold of 28 mm or more (P < .001; Hazard ratio 4.7[2.7-8.2]). The diameter of the false lumen was associated with night-time systolic BP (P = .025; r = .2), 24-hour pulse pressure (P = .002; r = .28), and night-time pulse pressure (P = .008; r = .24).

CONCLUSION

The risk of new aortic events following type A acute aortic syndrome is associated with the size of the residual false lumen, but not directly with BP parameters. Night-time BP parameters are associated with the size of the residual false lumen.

Insights From the International Registry of Acute Aortic Dissection: A 20-Year Experience of Collaborative Clinical Research

Acute aortic dissection (AAD) is a life-threatening condition associated with high morbidity and mortality rates, and it remains a challenge to diagnose and treat. The International Registry of Acute Aortic Dissection was established in 1996 with the mission to raise awareness of this condition and provide insights to guide diagnosis and treatment. Since then, >7300 cases have been included from >51 sites in 12 countries. Although presenting symptoms and physical findings have not changed significantly over this period, the use of computed tomography in the diagnosis has increased, and more patients are managed with interventional procedures: surgery in type A AAD and endovascular therapy in type B AAD; with these changes in care, there has been a significant decrease in overall in-hospital mortality in type A AAD but not in type B AAD. Herein, we summarized the key lessons learned from this international registry of patients with AAD over the past 20 years.

Type 2 diabetes mellitus reduces clinical complications and mortality in Stanford type B aortic dissection after thoracic endovascular aortic repair: A 3-year follow-up study

BACKGROUND

Previous studies have demonstrated that type 2 diabetes mellitus (T2DM) is negatively correlated with the occurrence of aortic dissection (AD). This study aimed to investigate the effects of T2DM on the prognosis of Stanford type B AD (STBAD) patients after thoracic endovascular aortic repair (TEVAR).

METHODS

STBAD patients (n = 141) who underwent TEVAR received an oral glucose tolerance test (OGTT) and were divided into a normal glucose (NG, n = 55) group, an abnormal glucose tolerance (AGT, n = 48) group and a T2DM (n = 38) group according to the results of the OGTT. Data on mortality, clinical complications, left ventricular (LV) remodeling and aortic remodeling were collected during the 3-year follow-up.

RESULTS

Lower mortality and fewer clinical complications after TEVAR were found in the T2DM group than in the NG group. Multivariate linear regression analysis showed that 2-hour postprandial glucose (Glu-2h) was negatively correlated with mortality and the occurrence of clinical complications in STBAD patients after TEVAR. In addition, better LV remodeling, larger true lumen areas and smaller false lumen areas in both the proximal aortas and abdominal aortas were observed in the T2DM group than in the NG group. Furthermore, no significant differences in mortality or clinical complications after TEVAR were found between the NG group and the AGT group or between the T2DM group and the AGT group.

CONCLUSION

During the 3-year follow-up period, mortality and clinical complications in STBAD patients after TEVAR were significantly reduced in the T2DM group. For STBAD patients who undergo TEVAR, properly relaxing of blood glucose control requirements may be beneficial for their prognosis.

[Type A intramural hematoma of aorta: An undervalued clinical entity]

Intramural hematoma of the ascending aorta occurs after rupture of the vasa vasorum. Previously considered as a first step of acute aortic dissection, it was later defined as a separate entity that may or may not lead to arterial dissection. The debate about the most appropriate treatment for a 69-year-old patient with intramural hematoma of the ascending aorta, led to this extensive review of the literature demonstrating that intramural hematoma type A is a life-threatening condition requiring urgent surgical support.

Influence of False Lumen Status on the Prognosis of Acute Type A Aortic Dissection without Urgent Surgical Treatment

AIM

Recently, much attention has been focused on partial thrombosis of the false lumen in patients with acute aortic dissection. However, its effect on clinical outcomes in these patients, especially in case of acute type A aortic dissection, has not been clearly elucidated. This study evaluated the influence of the false lumen status, including partial thrombosis, on short-term clinical outcomes in acute type A aortic dissection patients without urgent surgical treatment.

METHODS

Sixty-two patients (29 males, mean age 73±13 years) with acute type A aortic dissection who did not receive urgent surgical treatment at four hospitals were enrolled. Patients were divided into three groups based on the false lumen status on enhanced computed tomography image (complete thrombosis, n=28; partial thrombosis, n=27; patent, n=7). Patients with partial thrombosis were further divided into two groups (thrombus-dominant, n=15; flow-dominant, n=12).

RESULTS

The short-term mortality rate (in-hospital and 30-day) was significantly higher in patients with a patent false lumen, while no significant difference was seen between the other two groups. Patients with flow-dominant partial thrombosis had significantly higher short-term mortality rate than those with thrombus-dominant partial thrombosis (in-hospital, p=0.001 and 30-day, p＜0.001).

CONCLUSIONS

The short-term mortality rate in acute type A aortic dissection patients without urgent surgical treatment was lower in patients with partial thrombosis of the false lumen than in those with a patent false lumen. Furthermore, patients with flow-dominant partial thrombosis had higher mortality rate than those with thrombus-dominant partial thrombosis.

False Lumen Status in Patients With Acute Aortic Dissection: A Systematic Review and Meta-Analysis

Background

The long‐term association between the status of the false lumen and poor patient outcomes in acute aortic dissection (AAD) remains unclear. This systematic review and meta‐analysis investigated whether the status of the false lumen was a predictor of poor long‐term survival in AAD.

Methods and Results

Eleven cohort studies (2924 participants) exploring the association between the false lumen status and long‐term outcomes (>1 year) in AAD were included. All studies reported multivariate‐adjusted hazard ratios (HRs) with 95% CIs for long‐term outcomes, according to false lumen status. Pooled HRs for mortality and aortic events were computed and weighted using generic inverse‐variance and random‐effect modeling. Residual patent false lumen was an independent predictor of long‐term mortality in AAD type A (HR, 1.71; 95% CI, 1.16–2.52; P=0.007) and type B (HR, 2.79; 95% CI, 1.80–4.32; P<0.001). AAD patients with residual patent false lumen exhibited an increased risk of aortic events (HR, 5.43; 95% CI, 2.95–9.99; P<0.001). Partial false lumen thrombosis was independently associated with long‐term mortality in type B AAD (HR, 2.24; 95% CI, 1.37–3.65; P=0.001). This association was not observed in AAD type A patients (HR, 1.75; 95% CI, 0.88–3.45; P=0.211).

Conclusions

The false lumen status influences late outcomes in AAD. Residual patent false lumen is independently associated with poor long‐term survival in AAD. However, only type B AAD patients with partial false lumen thrombosis had an increased late mortality risk.

Hybrid repair of type A acute aortic dissections with the Lupiae technique: ten-year results

OBJECTIVES

Replacing the ascending aorta and the arch in patients with type A acute aortic dissection achieves good short-term results, but several patients are left with distal intimal tears or a patent false lumen in the descending aorta. In this series, we report the 10-year experience with the Lupiae technique, a hybrid aortic repair technique for patients with type A acute aortic dissection.

METHODS

From 2003 to 2013, 89 patients with type A acute aortic dissections underwent replacement of the ascending aorta, the arch, and the rerouting of the neck vessels on the ascending aorta, creating a proximal Dacron landing zone for a completion with thoracic endovascular aortic repair if necessary.

RESULTS

In-hospital mortality was 8.9%. In 16 patients, the false lumen healed spontaneously, whereas the remaining 65 patients underwent thoracic endovascular aortic repair. One patient died after thoracic endovascular aortic repair. Eighty patients were followed up. Complete thrombosis of the false lumen was obtained in 93.8% of patients. The median follow-up was 46 ± 35 months. Overall 8-year survival was 93.7% ± 5%, 100% for patients with spontaneously healed residual false lumen after just type A acute aortic dissection repair and 92.3% ± 7.7% for patients who underwent thoracic endovascular aortic repair after type A acute aortic dissection repair. In 10 years, 1 patient underwent a reoperation on the distal aorta (1.25%).

CONCLUSIONS

The availability of a Dacron landing zone on the distal ascending aorta after type A acute aortic dissection repair allows the exclusion, with a thoracic endovascular aortic repair, of any residual intimal tear refilling a patent false lumen. This approach seems to be associated with a high probability of false lumen thrombosis and low rates of reoperations on the distal aorta.