Thoracic endovascular aortic repair for the ascending aorta: experience and pitfalls

Dynamic aortic changes during the cardiac cycle in patients with aortic valve disease analyzed by computed tomography combined with PhyZiodynamics software

BACKGROUND

Endovascular therapy for the ascending aorta is expected in the future, but the dynamic changes in the ascending aorta are unclear.

PURPOSE

The purpose of the present study was to evaluate dynamic changes in the aortic cross-sectional area and examine related determinants.

METHODS

The subjects included 75 patients (aortic regurgitation [AR] in 18 patients, aortic stenosis [AS] in 46 patients, and 11 controls) who underwent dynamic computed tomography (CT) prior to cardiac treatment. According to the centerline method, the cross-sectional areas of the ascending and descending aortas at the same level were analyzed. The rate of change from the minimum value to the maximum value in one heartbeat and peak rate of change in cross-sectional area (peak area change) were measured.

RESULTS

The rates of change of the ascending and descending aortas were 4.4% and 6.4% (P < 0.05) and the peak area change was 0.3 mm2/msec vs. 0.2 mm2/msec (P < 0.05), respectively. In both the ascending and descending aortas, the rate of change and the peak area change were significantly greater in the AR group than in the AS and control groups. Results of the multiple regression analysis showed that greater stroke volumes (SVs) were associated with greater change in the ascending aorta and a faster momentary expansion rate. Furthermore, it was observed that the momentary expansion rate declined with age.

CONCLUSION

The ascending aortic diameter changes significantly in one heartbeat and differs depending on AR, age, and SV.

TRIAL REGISTRATION NUMBER

17 - 006.

DATE OF REGISTRATION

May 29, 2017 Retrospectively registered.

Tailored approach and outcomes of aortic arch reconstruction after acute type A dissection repair

OBJECTIVE

After limited root/ascending with or without hemiarch repair for acute type A aortic dissection (ATAAD), 20% to 30% of patients require distal reintervention, frequently for arch pathology. In this report, we describe an institutional algorithm for arch management after previous limited ATAAD repair and detail operative and long-term outcomes.

METHODS

From August 2005 to April 2021, 71 patients status post previous limited ATAAD repair underwent reoperative arch repair involving zones 1 to 3 for aneurysmal degeneration of residual arch dissection including complete cervical debranching with zone 0/1 thoracic endovascular aortic repair in 6 (8%), open total arch in 13 (18%), type I hybrid arch repair in 23 (32%), and type II/III hybrid arch repair in 29 (41%).

RESULTS

Mean age was 59 ± 12 years; time from index ATAAD repair to reoperation was 4 (interquartile range, 2-9) years. There were 2 (2.8%) in-hospital deaths and 2 (2.8%) postdischarge deaths within 30 days of surgery. Three patients suffered stroke (4.2%) and 2 (2.8%) had acute renal failure requiring dialysis. Overall Kaplan-Meier survival was 78%, 70%, and 58% at 1, 3, and 5 years, respectively. Institutional experience appeared to play a significant role in early and late outcomes, because there have been no operative mortalities in the past 9 years and improved survival of 87% versus 66%, 79% versus 58%, and 79% versus 40% at 1, 3, and 5 years in comparisons of the past 9 years with the previous era (P = .01).

CONCLUSIONS

Aneurysmal degeneration of residual arch dissection after limited ATAAD repair presents a complex reoperative challenge. An algorithmic operative approach tailored to patient anatomy and comorbidities yields excellent early and late outcomes, which continue to improve with increasing institutional experience.

Thoracic endovascular aortic repair of an ascending aortic pseudoaneurysm

A 74-year-old man with a history of two thoracic aortic repairs, including a modified Bentall procedure using a mechanical valve and total arch replacement, was referred to our hospital with the development of hoarseness. Computed tomography revealed an anastomotic pseudoaneurysm between the prosthetic grafts in the ascending aorta. Two aortic cuffs for abdominal aorta were deployed through the left axillary artery using a transcatheter aortic valve replacement guidewire placed at the supra-aortic mechanical valve during ventricular rapid pacing and were successfully covered with an inlet to the pseudoaneurysm on postoperative computed tomography. The postoperative course was favorable.

Ascending Aortic Endograft and Thoracic Aortic Deformation After Ascending Thoracic Endovascular Aortic Repair

PURPOSE

We aim to quantify multiaxial cardiac pulsatility-induced deformation of the thoracic aorta after ascending thoracic endovascular aortic repair (TEVAR) as a part of the GORE ARISE Early Feasibility Study.

MATERIALS AND METHODS

Fifteen patients (7 females and 8 males, age 73±9 years) with ascending TEVAR underwent computed tomography angiography with retrospective cardiac gating. Geometric modeling of the thoracic aorta was performed; geometric features including axial length, effective diameter, and centerline, inner surface, and outer surface curvatures were quantified for systole and diastole; and pulsatile deformations were calculated for the ascending aorta, arch, and descending aorta.

RESULTS

From diastole to systole, the ascending endograft exhibited straightening of the centerline (0.224±0.039 to 0.217±0.039 cm^-1, p<0.05) and outer surface (0.181±0.028 to 0.177±0.029 cm^-1, p<0.05) curvatures. No significant changes were observed for inner surface curvature, diameter, or axial length in the ascending endograft. The aortic arch did not exhibit any significant deformation in axial length, diameter, or curvature. The descending aorta exhibited small but significant expansion of effective diameter from 2.59±0.46 to 2.63±0.44 cm (p<0.05).

CONCLUSION

Compared with the native ascending aorta (from prior literature), ascending TEVAR damps axial and bending pulsatile deformations of the ascending aorta similar to how descending TEVAR damps descending aortic deformations, while diametric deformations are damped to a greater extent. Downstream diametric and bending pulsatility of the native descending aorta was muted compared with that in patients without ascending TEVAR (from prior literature). Deformation data from this study can be used to evaluate the mechanical durability of ascending aortic devices and inform physicians about the downstream effects of ascending TEVAR to help predict remodeling and guide future interventional strategies.

CLINICAL IMPACT

This study quantified local deformations of both stented ascending and native descending aortas to reveal the biomechanical impact of ascending TEVAR on the entire thoracic aorta, and reported that the ascending TEVAR muted cardiac-induced deformation of the stented ascending aorta and native descending aorta. Understanding of in vivo deformations of the stented ascending aorta, aortic arch and descending aorta can inform physicians about the downstream effects of ascending TEVAR. Notable reduction of compliance may lead to cardiac remodeling and long-term systemic complications. This is the first report which included dedicated deformation data regarding ascending aortic endograft from clinical trial.

Animal study on adjustable pre fenestration aortic stent graft

OBJECTIVES

To isolate aortic arch pathologies and keep the branches superior in arch patent, it always need physicians to do in-vivo fenestration or in-situ fenestration when performing the thoracic endovascular aortic repair (TEVAR). However, both of those fenestration techniques need structure modification of the stent-graft, which may affect their long-term stability. We designed an adjustable pre-fenestration aortic stent-graft to treat pathologies in this area and obtained a patent branch arteries. This study used this new designed stent-graft to perform fenestrated-TEVAR (f-TEVAR) in canine aorta. This study aims to identify its feasibility and safety through animal experiments, which might provide preliminary data for potential human implantation.

METHODS

A total of 8 Labrador Retrievers were underwent f-TEVAR by using the new devices. Digital subtraction angiography was performed before and after f-TEVAR to evaluate the success of the procedures. All the canines were divided into a 4-week group (feeding for 4 weeks after operation) and a 12-week group (feeding for 12 weeks after operation). Computed tomography angiography (CTA) were performed before euthanasia.

RESULTS

The success rate of operation was 100%. During the operation, there was no accident of major bleeding or failure to be released by fenestration. Adjustable fenestration worked well. No stent-graft migration was found in CTA at 4 weeks and 12 weeks after the operation. All branch arteries kept by the adjustable fenestration were patent.

CONCLUSIONS

The result of feasibility and safety of the new designed adjustable pre-fenestration aortic stent-graft in f-TEVAR of canine is acceptable. This study provides a reference for further optimization of this stent and human f-TEVAR implantation involving aortic arch lesions.

Endovascular repair of the ascending aorta: the last frontier

Different pathologies of the ascending aorta (AA), including aneurysms, acute and chronic dissections, and pseudoaneurysms, have been treated with open surgical repair with very good results, especially at aortic centers of excellence. There is, however, a subset of patients for whom open surgery is considered to pose high or prohibitive risk. These patients can benefit from a less invasive approach with catheters and wires, percutaneous techniques and stent grafts. However, the existing technology was developed to treat descending thoracic aortic pathologies; it is not approved for use in the AA by the US Food and Drug Administration (FDA). The devices used for the descending thoracic aorta (DTA) have certain size and design limitations that make their application to the AA cumbersome at times. As a result, custom-made endografts have been used to treat pathologies in the AA, although their use is feasible only in elective procedures. In addition, the AA has specific anatomic and physiologic characteristics that raise concerns about the long-term durability of the current technology. In this review, we outline the limitations, challenges and current status of endovascular technology to treat pathologies of the AA.

Surgical outcomes analysis in patients with uncomplicated acute type A aortic dissection: a 13-year institutional experience

This retrospective study aimed to clarify the short-term and mid-term outcomes of and prognostic factors for patients who underwent surgical repair for uncomplicated acute type A aortic dissection (ATAAD). Between January 2007 and June 2019, 603 consecutive patients underwent ATAAD repair at our institution. According to patients’ preoperative presentations and imaging studies, uncomplicated ATAAD was found in 276 (45.8%) patients by excluding preoperative complicated factors. Patients with uncomplicated ATAAD were classified into the survivor (n = 243) and non-survivor (n = 33) groups. Clinical features, surgical information, and postoperative complications were compared. Three-year survival and freedom from reoperation rates for survivors were analyzed using the Kaplan–Meier actuarial method. The in-hospital surgical mortality rate of uncomplicated ATAAD patients was 11.9%. The non-survivor group had a higher rate of postoperative malperfusion-related complications, and a multivariate analysis revealed that repeat surgery, retrograde cerebral perfusion, and intraoperative extracorporeal membrane oxygenation support were predictors of in-hospital mortality. In the survivor group, 3-year cumulative survival and freedom from aortic reoperation rates were 89.6% (95% confidence interval [CI] 84.8–92.9%) and 83.1% (95% CI 76.8–87.7%), respectively. In conclusion, uncomplicated and complicated ATAAD rates were similar; the short-term and mid-term surgical outcomes in patients with uncomplicated ATAAD were generally acceptable.

Late Type A Dissection After Transfemoral Aortic Valve Replacement

An 87-year-old woman had residual moderate to severe aortic insufficiency following transcatheter aortic valve replacement. A year later, she developed extensive Stanford type A aortic dissection originating at the supra-annular aortic edge of the transcatheter aortic valve replacement nitinol frame. Dissection repair, frozen elephant trunk with exclusion of prior insufficiency while preserving the transcatheter aortic valve replacement valve was performed. (Level of Difficulty: Beginner.)

Endo-Bentall for proximal aortic dissection: from conception to application

The endovascular treatment of pathologies of the ascending aorta has not been incorporated into routine clinical practice. The aim of this article is to provide an overview of the endovascular treatment of pathologies of the ascending aorta, particularly type A aortic dissection. A thorough analysis and discussion of anatomical, physiological, clinical and technical challenges, and obstacles is performed. Conventional straight stent-grafts alone are not capable of fixing the entire complex underlying problem in the vast majority of patients with acute type A aortic dissection. An endovascular valve-carrying conduit consisting of a proximal transcatheter aortic valve connected to a covered stent-graft would be able to close a primary entry tear in the ascending aorta, ensure coronary perfusion, initiate true lumen expansion, treat malperfusion, treat aortic regurgitation, drain any pericardial effusion through a transapical approach, and possibly stabilize the distal aorta. Two thirds of all patients with acute aortic dissection are potential candidates for endovascular treatment, and the concept may help to significantly improve survival in patients with acute aortic dissection.

Endovascular Treatment of the Ascending Aorta: is this the Last Frontier in Aortic Surgery?

Regardless the successful treatment of the descending aorta with endovascular prosthesis, for the ascending aorta segment, because of several anatomic and physiologic issues, this technique has been considered an alternative only for high-risk or inoperable patients. Despite restricted indications, hundreds of treatments have been performed worldwide, demonstrating its safety and reproducibility if it is done in high-quality centers. Therefore, understanding patients' selection criteria and technique limitations are critical to its application.

Early and late outcomes of aortic surgery under hypothermic circulatory arrest in the elderly: a single center study

BACKGROUND

With the progressive aging of the population, aortic surgeons are caring for an increasing number of elderly patients. The objective of this study was to analyze early and late outcomes of aortic surgery with hypothermic circulatory arrest in patients aged 70 and above at our institution.

METHODS

We performed a retrospective cohort study including every patient aged 70 years or older who underwent aortic surgery with hypothermic circulatory arrest between January 1995 and June 2016 at our institution. Operative results were compared with the contemporary younger counterparts aged <70 years. In-hospital mortality and postoperative stroke were primary outcomes of interest. The main secondary outcomes included acute renal failure, reoperation for bleeding, and spinal cord injury.

RESULTS

In the study population, the in-hospital mortality was 16.8% (21/125). Ten (8.0%) patients presented postoperative stroke, and 6 had temporary neurologic disturbance (4.8%). Spinal cord injury occurred in 1 (0.8%) patient. For elective interventions and type A aortic dissections, the in-hospital mortality and stroke rates were 4.6% (3/65) and 7.7% (5/65), 26.8% (11/41) and 12.2% (5/41), respectively. The proportion of non-elective interventions, including type A aortic dissection, and the type of neuroprotective strategy were similar in septuagenarians and younger patients. Patients aged ≥70 had significant shorter cardiopulmonary bypass, myocardial ischemia, and circulatory arrest durations, compared to their younger counterparts. The in-hospital mortality of septuagenarians and younger patients were similar for elective surgery (4.6% vs. 4.7%, P=0.900) and aortic dissections (26.8% vs. 15.1%, P=0.107). There was no statistically significant difference between the two age groups regarding postoperative stroke, spinal cord injury, renal failure requiring dialysis or reintervention for bleeding. Estimated 1-, 3-, and 5-year survival was 78.0%, 70.6%, and 65.7%, respectively. The 5-year survival for elective surgery was 74.9% and 56.0% for non-elective procedures.

CONCLUSIONS

Aortic surgery with circulatory arrest in the elderly demonstrated favorable early and late results when compared with younger individuals, with an acceptable operative risk even under emergency conditions, and should not be denied only because of the chronological age of the patients.