Treating lower extremity malperfusion syndrome in acute type A aortic dissection with endovascular revascularization followed by delayed aortic repair

The Management of the Aortic Arch in Type A Aortic Dissection: Replace, Repair with the AMDS, or Leave for Another Day?

OBJECTIVES

Acute type A aortic dissection (ATAAD) is a life-threatening condition that requires emergent surgical intervention. Numerous surgical approaches exist for ATAAD, and controversy remains regarding the optimal arch interventions for ATAAD patients. Aortic Arch Interventions: Approaches to ATAAD repair include hemiarch repair or extended arch repairs, including the hemiarch with a hybrid stent implantation, such as the AMDS hybrid Prosthesis, total arch replacement (TAR), and the use of an elephant trunk and frozen elephant trunk. While indications for each procedure exist, such as entry tears in the arch, arch aneurysms, and head vessel communications for TAR and malperfusion and a reduced risk of distal anastomotic new entry tears in Debakey I aortic dissection for the AMDS and frozen elephant trunks, the optimal intervention depends on numerous factors. Surgeon and center experience, resource availability, patient risk, and anatomy all contribute to the decision-making process. TAR has improved in safety over the years and has been demonstrated to be comparable to the hemiarch repair in terms of safety in many settings. TAR may also prevent adverse remodeling and can effectively treat more distal diseases, the presence of arch tears, arch aneurysms, and branch vessel involvement or malperfusion.

CONCLUSIONS

Numerous surgical approaches exist to manage ATAAD, allowing for the surgeon to tailor the repair to the individual patient and pathology. TAR allows for single or staged repair of extensive pathologies and can address distal entry tears, the aneurysmal arch, and head vessel pathologies. In cases with malperfusion, an AMDS can be used in many cases. The management strategy for ATAAD should always involve performing the best surgery for the patient, although in cases where a total arch is indicated but cannot be performed safely by a non-aortic surgeon, the safest approach may be to perform a hemiarch initially and to plan for an elective arch reoperation in the case it is required following close surveillance.

Malperfusion, Malperfusion Syndrome, and Mesenteric Ischemia in Aortic Dissection

Aortic malperfusion occurs in a significant percentage of patients with acute aortic dissection, and causes malperfusion syndrome, the clinical entity defined by end organ ischemia, in 10-33% of patients. Malperfusion syndrome can be rapidly lethal and can involve the coronary, cerebral, visceral, or lower extremity vessels. Depending on presentation, it may be appropriately and well treated with endovascular fenestration prior to definitive central aortic repair.

Predictors of Late Adverse Events in Patients with Surgically Treated Type I Aortic Dissection

OBJECTIVE

Residual aortic dissection (AD) following DeBakey type I AD repair is associated with a high rate of adverse events that need additional intervention or surgery. This study aimed to identify clinical and early post-operative computed tomography angiography (CTA) imaging factors associated with adverse events in patients with type I AD after ascending aorta replacement.

METHODS

This single centre, retrospective cohort study included consecutive patients with type I AD who underwent ascending aorta replacement from January 2011 to December 2017 and post-operative CTA within three months. The primary outcome was AD related adverse events, defined as AD related death and re-operation due to aortic aneurysm or impending rupture. The location and size of the primary intimal tears, aortic diameter, and false lumen status were evaluated. Regression analyses were performed to identify factors associated with AD related adverse events. A decision tree model was used to classify patients as high or low risk.

RESULTS

Of 103 participants (55.43 ± 13.94 years; 49.5% male), 24 (23.3%) experienced AD related adverse events. In multivariable Cox regression analysis, connective tissue disease (hazard ratio [HR] 15.33; p < .001), maximum aortic diameter ≥ 40 mm (HR 4.90; p < .001), and multiple (three or more) intimal tears (HR 7.12; p < .001) were associated with AD related adverse events. The three year cumulative survival free from AD related events was lower in the high risk group with aortic diameter ≥ 40 mm and multiple intimal tears (41.7% vs. 90.9%; p < .001).

CONCLUSION

Early post-operative CTA findings indicating a maximum aortic diameter ≥ 40 mm and multiple intimal tears may predict a higher risk of adverse events. These findings suggest the need for careful monitoring and more vigilant management approaches in these cases.

Treatment Strategies for Acute Aortic Dissection With Malperfusion: A Retrospective Study

BACKGROUND

Aortic dissection with malperfusion necessitates emergency surgery and is associated with poor outcomes. Therefore, in this study, we analyzed patients' treatment courses from the initial management to hospital discharge in cases of acute aortic dissection (AAD) with malperfusion and investigated the risk factors associated with mortality.

METHODS

We evaluated cases of AAD with malperfusion treated at our institution over a 16-year period from 2007 to 2022. The primary endpoint was in-hospital mortality. The study's primary outcome measure was mortality during hospitalization. We collected and analyzed data encompassing preoperative patient characteristics, Stanford classification, sites of preoperative malperfusion, surgical techniques employed, and postoperative complications. These variables were examined to identify factors associated with in-hospital mortality.

RESULTS

During the study period, 366 patients were admitted with AAD, 102 of whom had malperfusion. There were 62 men (61%) and 40 women (39%), with a mean age of 64 ± 13 years (range: 28-87 years). According to the Stanford classification, 75 (74%) and 27 (26%) patients had type A and B aortic dissection, respectively, and 29 patients (28%) presented with shock. Preoperative malperfusion sites included the brain, coronary arteries, abdominal viscera, limbs, and spinal cord in 40 (39%), 10 (10%), 34 (33%), 52 (51%), and six (6%) patients, respectively. Eleven (11%) patients required immediate intervention in the emergency department. The treatments administered to the patients were as follows: ascending aortic replacement, 30 (29%) patients; aortic arch replacement, 34 (33%) patients; root replacement, three (3%) patients; thoracic endovascular aortic repair (TEVAR), 12 (12%) patients; non-anatomic bypass, five (5%) patients; and conservative management, five (5%) patients. In-hospital mortality occurred in 23 (23%) patients. Multivariate logistic regression analysis identified preoperative coronary malperfusion as an independent risk factor of mortality.

CONCLUSION

Preoperative coronary malperfusion is an independent risk factor for in-hospital mortality in patients with AAD presenting with malperfusion.

Renal Dysfunction at Discharge and Long-Term Survival in Acute Type A Aortic Dissection

INTRODUCTION

We aimed to investigate the association between renal dysfunction at discharge and long-term survival in acute type A aortic dissection (ATAAD) patients following surgery.

METHODS

From 2000 to 2021, 784 patients underwent aortic repair for an ATAAD. Patients were stratified based on creatinine (Cr) level at discharge alive or dead: normal Cr (n = 582) and elevated Cr defined as >1.3 mg/dL for males and >1.0 mg/dL for females or on dialysis at discharge (n = 202).

RESULTS

Preoperatively, both groups had similar rates of comorbidities except for the elevated-Cr group which had more diabetes, chronic obstructive pulmonary disease, and chronic and acute renal insufficiency. Both groups had similar open ATAAD repair procedures. Postoperative outcomes in the elevated-Cr group were significantly worse, including six times higher operative mortality (20% versus 3.4%, P < 0.0001). The landmark long-term survival after discharge alive was significantly worse in the elevated-Cr group than the normal-Cr group (10-y survival: 48% versus 69%, P = 0.0009). The elevated Cr on dialysis at discharge group had significantly worse five-year survival (40%) than the elevated Cr not on dialysis at discharge group (80%, P = 0.02) and the normal-Cr group (87%, P < 0.0001). Additionally, the elevated Cr not on dialysis had a worse five-year survival than the normal-Cr group (80% versus 87%, P = 0.02). Elevated Cr at discharge on dialysis was a significant risk factor for late mortality (hazard ratio = 4.22, 95% confidence interval: [2.07, 8.61], P < 0.0001).

CONCLUSIONS

Renal dysfunction at discharge was associated with significantly decreased short-term and long-term survival following open ATAAD repair. Surgeons should aggressively prevent renal dysfunction, especially new-onset dialysis, at discharge as it is correlated with significantly worse short-term and long-term outcomes.

Natural history of visceral branch artery dissections and the influence of concurrent aortic dissection on overall and intervention-free survival

OBJECTIVE

Visceral branch artery dissection (VBAD) is uncommon and may occur with or without an associated aortic dissection (AD). We hypothesized that isolated VBAD would have a more benign clinical course than those with concurrent AD and compared survival outcomes stratified based on aortic involvement.

METHODS

VBAD over a 5-year period were identified using International Classification of Diseases codes. Data related to patient demographics, comorbid conditions, clinical presentation, management (including procedural interventions), and survival were obtained from medical records. Anatomic imaging studies were reviewed to characterize anatomy, including the presence or absence of concurrent AD. Overall survival and intervention-free survival were evaluated using Kaplan-Meier and Cox proportional hazards models.

RESULTS

A total of 299 VBAD were identified, 174 of which were isolated VBAD and 125 were associated with concurrent AD. Seventy-one percent of patients were men, 77% were White, and 85% were non-Hispanic. The mean age was 61.1 ± 14.4 years. The mean follow-up was 53.2 ± 50.0 months. The estimated overall survival was 88.2% and the estimated overall intervention-free survival was 55.6% at 12 months. Isolated VBAD had better overall survival than those with concurrent AD (69.2% vs 32.4%; P < .001). Concurrent AD was also associated with inferior intervention-free survival (57.5% vs 7.3%; P < .001). Acute presentation was associated with decreased intervention-free survival (86.1% vs 13.4%; P < .001). Acute presentation was also associated with decreased overall survival in patients with isolated VBAD (60.8% vs 80.0% at 180 months; P < .001) and inferior intervention-free survival (48.4% vs 69.5% at 180 months; P < .001) in the subgroup of patients with isolated VBAD. Multivariable Cox models identified that age (hazard ratio [HR]: 1.05, standard deviation [SD]: 0.02; P = .001) was associated with inferior survival and renal dissections (HR: 3.08, SD: 0.99; P = .001) or mesenteric and renal dissections (HR: 3.39, SD: 1.44; P = .004) were associated with inferior intervention-free survival.

CONCLUSIONS

Isolated VBAD has superior overall and intervention-free survival to those associated with concurrent AD. The absence vs presence of aortic involvement is useful for risk stratification and may support tailored approaches to the frequency of imaging surveillance.

Lower-extremity malperfusion syndrome in patients undergoing proximal aortic surgery for acute type A aortic dissection

Objective

Data regarding management of lower-extremity malperfusion in the setting of type A aortic dissection are limited. This study aimed to compare acute type A aortic dissection with lower-extremity malperfusion outcomes in patients undergoing lower-extremity revascularization with no revascularization.

Methods

Consecutive patients undergoing acute type A aortic dissection surgery were identified from a prospectively maintained database. Perioperative variables were compared between patients with and without lower-extremity malperfusion. Factors associated with lower-extremity malperfusion, revascularization, and mortality were determined using univariable Cox regression and Firth's penalized likelihood modeling.

Results

From January 2007 to December 2021, 601 patients underwent proximal aortic repair for acute type A aortic dissection at a quaternary care center. Of these, 85 of 601 patients (14%) presented with lower-extremity malperfusion and were more often male (P = .02), had concomitant moderate or greater aortic insufficiency (P = .05), had lower ejection fraction (P = .004), had preoperative dialysis dependence (P = .01), and had additional cerebral, visceral, and renal malperfusion syndromes (P < .001). Kaplan-Meier estimated survival fared worse with lower-extremity malperfusion compared with no lower-extremity malperfusion at 1, 5, and 10 years (84% vs 77%, 74% vs 71%, 65% vs 52%, respectively, P = .03). In the lower-extremity malperfusion group, 15 of 85 patients (18%) underwent lower-extremity revascularization without significant differences in postoperative morbidity and mortality compared with patients not undergoing revascularization. Need for peripheral revascularization was associated with peripheral vascular disease (hazard ratio, 3.7 [1.0-14.0], P = .05) and pulse deficit (hazard ratio, 5.6 [1.3-24.0], P = .02) at presentation.

Conclusions

Patients presenting with type A aortic dissection and lower-extremity malperfusion have worse overall survival compared with those without lower-extremity malperfusion. However, not all patients with type A aortic dissection and lower-extremity malperfusion require revascularization.