Axillary Cannulation for Proximal Aortic Surgery is as Safe in the Emergent Setting as in Elective Cases

Low-flow perfusion technique for shaggy aortic arch

BACKGROUND

The most common complication of thoracic aortic disease with shaggy aorta is cerebral infarction. We have performed "low-flow perfusion" as a method of extracorporeal circulation to prevent cerebral embolism in patients with strong atherosclerotic lesions in the aortic arch.

METHODS

"Low-flow perfusion" is a method in which cardiopulmonary bypass is started by partial blood removal, approaching deep hypothermia while maintaining self-cardiac output. We compared the outcomes of 12 patients who underwent the "low-flow perfusion" method (Group L) with those of 12 who underwent normal extracorporeal circulation (Group N) during aortic arch surgery since 2019.

RESULTS

Group L consisted of 8 males with an average age of 73 years old, and Group N consisted of 6 males with an average age of 73 years old. The average time from the start of cooling to ventricular fibrillation was 9.5 min in Group L and 3.6 min in Group N (p < 0.01). The eardrum temperature when ventricular fibrillation was reached was 28.2 °C in Group L and 32.5 °C in Group N (p = 0.01). A blood flow analysis also revealed low wall shear stress on the lesser curvature of the aortic arch.

CONCLUSION

With this method, the intracranial temperature was sufficiently low at the time of ventricular fibrillation, and there was no need to increase the total pump flow. The low-flow perfusion method can prevent cerebral embolism by preventing atheroma destruction by the blood flow jet while maintaining the self-cardiac output during the cooling process.

The Role of Deep Hypothermia in Cardiac Surgery

Hypothermia is defined as a decrease in body core temperature to below 35 °C. In cardiac surgery, four stages of hypothermia are distinguished: mild, moderate, deep, and profound. The organ protection offered by deep hypothermia (DH) enables safe circulatory arrest as a prerequisite to carrying out cardiac surgical intervention. In adult cardiac surgery, DH is mainly used in aortic arch surgery, surgical treatment of pulmonary embolism, and acute type-A aortic dissection interventions. In surgery treating congenital defects, DH is used to assist aortic arch reconstructions, hypoplastic left heart syndrome interventions, and for multi-stage treatment of infants with a single heart ventricle during the neonatal period. However, it should be noted that a safe duration of circulatory arrest in DH for the central nervous system is 30 to 40 min at most and should not be exceeded to prevent severe neurological adverse events. Personalized therapy for the patient and adequate blood temperature monitoring, glycemia, hematocrit, pH, and cerebral oxygenation is a prerequisite and indispensable part of DH.

Combined femoral and axillary perfusion strategy for Stanford type a aortic dissection repair

Background

The optimal cannulation strategy in surgery for Stanford type A aortic dissection is critical to patient survival but remains controversial. Different cannulation strategies have their own advantages and drawbacks during cardiopulmonary bypass. Our centre used a combined femoral and axillary perfusion strategy for the surgical treatment of type A aortic dissection. The purpose of this study was to review and clarify the clinical outcome of femoral artery cannulation combined with axillary artery cannulation for the treatment of Stanford type A aortic dissection.

Methods

We performed a retrospective study that included 327 patients who were surgically treated for type A aortic dissection in our institution from January 2017 to June 2019. Femoral and axillary artery cannulation was used to establish cardiopulmonary bypass in patients with type A aortic dissection. The demographic data, surgical data, and clinical results of the patients were calculated.

Results

Femoral artery combined with axillary artery cannulation was technically successful in 327 patients. The cardiopulmonary bypass time was 141.60 ± 34.89 min, and the selective antegrade cerebral perfusion time was 14.94 ± 2.76 min. The early mortality rate was 3.06%. The incidence of permanent neurologic dysfunction was 0.92%. Sixteen patients had postoperative renal insufficiency, and five patients had liver failure.

Conclusion

Femoral artery combined with axillary artery cannulation for type A aortic dissection can significantly improve the prognosis of patients, especially in terms of cerebral protection, and can reduce the occurrence of adverse malperfusion syndrome and neurological complications.

Axillary Artery Cannulation in Acute Aortic Dissection: A Word of Caution

Arterial cannulation into the right axillary artery is a commonly adopted perfusion strategy in the treatment of acute aortic dissection. Here we describe our experience of accidentally cannulating the axillary artery in a case of acute aortic dissection with an aberrant right subclavian artery, which was missed preoperatively because its proximal segment was malperfused by the dissection and thereby not enhanced. The rapid hemodynamics collapse at the start of the bypass was reversed by prompt switching to femoral perfusion. Postoperative follow-up computed tomographic angiography revealed a well-perfused right aberrant subclavian artery. Surgeons should be aware of an aortic arch anomaly whenever performing an axillary artery cannulation.

Right Axillary Artery Cannulation in Aortic Valve Replacement

OBJECTIVE

This retrospective study aimed to evaluate the results of our experience with axillary artery cannulation via a side graft in aortic valve replacement in patients with ascending aortic atherosclerotic disease.

METHODS

From January 2002 to 2012, we operated on 76 patients for aortic valve disease with the use of the axillary artery for arterial inflow in our institute. The indications for cannulation of the axillary artery were aortic aneurysm in 37 patients, severe aortic atherosclerosis in 28 patients, and re do surgery in 11 patients.

RESULTS

Right axillary artery cannulation via a side graft provides sufficient antegrade aortic flow of 2.6 ± 0.1 L/m(2) during cardiopulmonary bypass. No additional arterial cannulation was necessary to obtain sufficient perfusion during cardiopulmonary bypass. Although permanent perioperative stroke was observed in two patients, this did not occur during the operation. There were no problems with cannulation or wound and graft infections. During the follow-up period, there were no thrombotic events due to an axillary graft stump in the right upper extremities.

CONCLUSIONS

Axillary artery cannulation via a side graft is a useful and safe option for cardiopulmonary bypass in patients with atherosclerotic disease of the ascending aorta undergoing aortic valve replacement.

Operative Strategies and Outcomes in Type a Aortic Dissection after the Enactment of a Multidisciplinary Aortic Surgery Team

Objective

The purpose of this study was to compare operative strategies and patient outcomes in acute type A aortic dissection (ATAAD) repairs before and after the implementation of a multi-disciplinary aortic surgery team.

Methods

Between May 2005 and July 2014, 101 patients underwent ATAAD repair at our institution. A dedicated multidisciplinary aortic surgery team (experienced aortic surgeon, perfusionists, cardiac anesthesiologists, nurses, and radiologists) was formed in 2010. We retrospectively compared ATAAD repair outcomes in patients before (2005–2009, N = 39) and after (2010–2014, N = 62) implementation of our program. Expected operative mortality was calculated using the International Registry of Acute Aortic Dissection preoperative predictive model.

Results

This study demonstrated a significant reduction in operative mortality after implementation of the aortic surgery program (30.8% vs. 9.7%; P = 0.014). There was also an increase in the complexity of surgical technique and perfusion strategies with fewer postoperative complications related to respiratory (P < 0.0001) and renal failure (P = 0.034). Baseline demographics were similar, and there was no statistically significant difference in International Registry of Acute Aortic Dissection predictive variables between the 2 groups. However, there was a 3.5-fold reduction in the observed-to-expected (O/E) operative mortality ratio. There was a 50% increase in volume with a significant number of patients being admitted directly to our aortic center for ATAAD repair, thus avoiding delay in operation related to transfers from a secondary hospital.

Conclusions

Patient outcomes are improved when the surgical treatment of ATAAD is managed by a high-volume multidisciplinary aortic surgery team.

Cannulation in aortic surgery: subclavian and axillary cannulation

Cannulation of peripheral vessels is being frequently used as a standard access for establishing cardiopulmonary bypass (CPB) in recent times. Apart from an increased use in patients requiring left ventricular circulatory support, i.e. either extracorporeal membrane oxygenation or long-term ventricular assist device systems, peripheral vessel cannulation is also beneficial in aortic surgery. The subclavian and axillary arteries are commonly used as sites for arterial cannulation to establish CPB during aortic surgery in many centres. Both cannulation sites enable safe implementation of CPB in patients requiring complex and difficult reoperations and those undergoing aortic surgery for acute type A aortic dissections or artherosclerotic aortic disease, in which cerebral perfusion is required. Here, we describe our techniques of direct cannulation of the subclavian and axillary artery for aortic arch surgery.

Outcomes following redo sternotomy for aortic surgery

Proximal thoracic aortic reconstruction performed with or without hypothermic circulatory arrest (HCA) is an effective surgical strategy for aortic pathology. In this study, the clinical outcomes of patients undergoing reoperative proximal thoracic aortic surgery were evaluated. A retrospective review was performed for reoperative proximal aortic surgery from 2004 to date. Patient data were abstracted from the society of thoracic surgeons (STS) institutional database and patient charts. Univariate analysis was conducted on the HCA group in order to determine the impact of variables on in-hospital mortality. Kaplan-Meier survival estimates were calculated for long-term survival analysis. One hundred and twenty-two patients were included in the analysis. Twenty-seven (22.1%) were female, and the mean age was 53.8 years. Seventy-seven (63.1%) patients had an aortic root replacement, and 93 (76.2%) patients underwent aortic arch replacement. Circulatory arrest was performed in 92 (75.4%) patients. Operative mortality occurred in 14 patients (11.5%). Complications included re-exploration for haemorrhage (nine patients, 7.4%), stroke (four, 3.3%), renal failure (13, 10.7%) and major adverse events (18, 14.8%). Univariate and multivariate analyses of HCA patients showed cardiopulmonary bypass (CPB) time, preoperative renal failure and prior coronary revascularization as independent predictors of mortality. Reoperative proximal aortic surgery can be performed with acceptable morbidity and mortality. These data also suggest that HCA represents a safe operative strategy for this patient population.

Evidence, lack of evidence, controversy, and debate in the provision and performance of the surgery of acute type A aortic dissection

Acute type A aortic dissection is a lethal condition requiring emergency surgery. It has diverse presentations, and the diagnosis can be missed or delayed. Once diagnosed, decisions with regard to initial management, transfer, appropriateness of surgery, timing of operation, and intervention for malperfusion complications are necessary. The goals of surgery are to save life by prevention of pericardial tamponade or intra-pericardial aortic rupture, to resect the primary entry tear, to correct or prevent any malperfusion and aortic valve regurgitation, and if possible to prevent late dissection-related complications in the proximal and downstream aorta. No randomized trials of treatment or techniques have ever been performed, and novel therapies-particularly with regard to extent of surgery-are being devised and implemented, but their role needs to be defined. Overall, except in highly specialized centers, surgical outcomes might be static, and there is abundant room for improvement. By highlighting difficulties and controversies in diagnosis, patient selection, and surgical therapy, our over-arching goal should be to enfranchise more patients for treatment and improve surgical outcomes.

Comparison of ascending aorta versus femoral artery cannulation for acute aortic dissection type A

BACKGROUND

The site of cannulation for repair of ascending aortic dissection remains controversial. We present our experience with ascending aortic cannulation for acute aortic dissection type A.

METHODS AND RESULTS

From January 1988 to September 2007, we operated on 242 patients for acute aortic dissection type A. Medical records of 235 patients who received ascending aortic cannulation or femoral cannulation were retrospectively reviewed. Long-term follow-up was complete in 97% of patients. Cannulation was accomplished in 82 patients through the ascending aorta and in 153 patients through the femoral artery. Preoperative patient characteristics were almost comparable between groups. Similarly, there were no differences in preoperative patient characteristics and intraoperative parameters including operation time, bypass time, cross-clamp time, hypothermic circulatory arrest time, and percentage of total arch replacement. The 30-day mortality rate was 14% in the aortic group and 23% in the femoral group (P=0.07), and incidence of stroke was 4.9% in the aortic group and 4.5% in the femoral group (P=0.86). During follow-up (mean, 5.5 years), survival at 5 years and 10 years was 65% and 41% in the aortic group and 64% and 46% in the femoral group, respectively (P=0.97).

CONCLUSIONS

The cannulation site should be chosen according to the patient's pathology and status, and the present study suggests that ascending cannulation in patients with acute aortic dissection type A can be a safe alternative, offering acceptable early and long-term outcomes.

Antegrade versus retrograde cerebral perfusion in relation to postoperative complications following aortic arch surgery for acute aortic dissection type A

BACKGROUND

Aortic arch surgery is impossible without the temporary interruption of brain perfusion and therefore is associated with high incidence of neurologic injury. The deep hypothermic circulatory arrest (HCA), in combination with antegrade or retrograde cerebral perfusion (RCP), is a well-established method of brain protection in aortic arch surgery. In this retrospective study, we compare the two methods of brain perfusion.

MATERIALS AND METHODS

From 1998 to 2006, 48 consecutive patients were urgently operated for acute type A aortic dissection and underwent arch replacement under deep hypothermic circulatory arrest (DHCA). All distal anastomoses were performed with open aorta, and the arch was replaced totally in 15 cases and partially in the remaining 33 cases. Our patient cohort is divided into those protected with antegrade cerebral perfusion (ACP) (group A, n = 23) and those protected with RCP (group B, n = 25).

RESULTS

No significant difference was found between groups A and B with respect to cardiopulmonary bypass-time, brain-ischemia time, cerebral-perfusion time, permanent neurologic dysfunction, and mortality. The incidence of temporary neurologic dysfunction was 16.0% for group A and 43.50% for group B (p = 0.04). The mean extubation time was 3.39 +/- 1.40 days for group A and 4.96 +/- 1.83 days for group B (p = 0.0018). The mean ICU-stay was 4.4 +/- 2.3 days for group A and 6.9 +/- 2.84 days for group B (p = 0.0017). The hospital-stay was 14.38 +/- 4.06 days for group A and 19.65 +/- 6.91 days for group B (p = 0.0026).

CONCLUSION

The antegrade perfusion seems to be related with significantly lower incidence of temporary neurological complications, earlier extubation, shorter ICU-stay, and hospitalization, and hence lower total cost.

The Aortic Arch and Ascending Aorta: Are They Within the Endovascular Realm?

Aneurysms involving the ascending aorta and arch have been historically treated with open surgical techniques requiring cardiopulmonary bypass and, in cases involving the aortic arch, utilizing deep hypothermic circulatory arrest. The reported rates of mortality range from 0% to 16.5% for surgery addressing ascending aorta and arch pathology, and stroke rates of 2% to 18%. These statistics highlight the invasiveness of these procedures. Continued development and evolution of endovascular stent-grafts has allowed for the application of endovascular interventions in the proximal descending thoracic aorta and visceral aortic segments. Based on early experiences, attention has been focused on the ascending aorta and aortic arch, where unique challenges exist and have been addressed by both extra-anatomic bypass and novel methods incorporating branched and fenestrated devices. Device evolution, coupled with increased experience by the aortic interventionalist, has resulted in successful cases of endovascular management of every section of the aorta, including aortic valve replacement. However, these experiences have also been accompanied by significant complications. In this light, new endovascular endeavors must be considered in the context of conventional treatment options, hybrid procedures, and novel branched devices. Patient factors, such as specific anatomic issues, comorbid diseases, and functional levels must play an important role in the determination of therapeutic options. Ultimately, a clinician who understands the disease and is familiar with all treatment options (interventional, medical, and open surgical) will be best suited to provide care for the aortic patient. Finally, as with any assessment of interventional strategies, rigorous follow-up and serial imaging are essential.