Antegrade Cerebral Perfusion With a Simplified Technique: Unilateral Versus Bilateral Perfusion

A challenging case of emergency redo surgery for acute type A aortic dissecting aneurysm of ascending and aortic arch with frozen elephant trunk following aortic root replacement

Redo ascending and aortic arch surgeries following previous cardiac or aortic surgery are associated with high risk of morbidity and mortality due to multiple factors included sternal re-entry injury, extensive aortic arch surgery, emergency aortic surgery, prolonged cardiopulmonary bypass duration, poor heart function, and patients with older age. Therefore, appropriate surgical strategies are important. We report a case of a 72-year-old gentleman with previous surgery of aortic root replacement who presented with acute Type A aortic dissecting aneurysm of ascending and aortic arch complicated with left hemothorax, which was successfully treated by emergency redo aortic surgery with frozen elephant trunk (FET) technique.

Association between Bilateral Selective Antegrade Cerebral Perfusion and Postoperative Ischemic Stroke in Patients with Emergency Surgery for Acute Type A Aortic Dissection-Single Centre Experience

Acute type A aortic dissection (ATAAD) is a surgical emergency with a mortality of 1-2% per hour. Since its discovery over 200 years ago, surgical techniques for repairing a dissected aorta have evolved, and with the introduction of hypothermic circulatory arrest and cerebral perfusion, complex techniques for replacing the entire aortic arch were possible. However, postoperative neurological complications contribute significantly to mortality in this group of patients. The aim of this study was to determine the association between different bilateral selective antegrade cerebral perfusion (ACP) times and the incidence of postoperative ischemic stroke in patients with emergency surgery for ATAAD. Patients with documented hemorrhagic or ischemic stroke, clinical signs of stroke or neurological dysfunction prior to surgery, that died on the operating table or within 48 h after surgery, from whom the postoperative neurological status could not be assessed, and with incomplete medical records were excluded from this study. The diagnosis of postoperative stroke was made using head computed tomography imaging (CT) when clinical suspicion was raised by a neurologist in the immediate postoperative period. For selective bilateral antegrade cerebral perfusion, we used two balloon-tipped cannulas inserted under direct vision into the innominate artery and the left common carotid artery. Each cannula is connected to a separate pump with an independent pressure line. Near-infrared spectroscopy was used in all cases for cerebral oxygenation monitoring. The circulatory arrest was initiated after reaching a target core temperature of 25-28 °C. In total, 129 patients were included in this study. The incidence of postoperative ischemic stroke documented on a head CT was 24.8% (31 patients), and postoperative death was 20.9% (27 patients). The most common surgical technique performed was supravalvular ascending aorta and Hemiarch replacement with a Dacron graft in 69.8% (90 patients). The mean cardiopulmonary bypass time was 210 +/- 56.874 min, the mean aortic cross-clamp time was 114.775 +/- 34.602 min, and the mean cerebral perfusion time was 37.837 +/- 18.243 min. Using logistic regression, selective ACP of more than 40 min was independently associated with postoperative ischemic stroke (OR = 3.589; 95%CI = 1.418-9.085; p = 0.007). Considering the high incidence of postoperative stroke in our study population, we concluded that bilateral selective ACP should be used with caution, especially in patients with severely calcified ascending aorta and/or aortic arch and supra-aortic vessels. All efforts should be made to minimize the duration of circulatory arrest when using bilateral selective ACP with a target of less than 30 min, in hypothermia, at a body temperature of 25-28 °C.

Unilateral versus bilateral antegrade cerebral perfusion during surgical repair for patients with acute type A aortic dissection

Objectives

To compare unilateral versus bilateral antegrade cerebral perfusion (ACP) techniques on cerebral protection during acute type A aortic dissection repair.

Methods

Using an institutional database, we retrospectively reviewed patients who underwent acute type A aortic dissection repair with selective ACP techniques from October 2008 to December 2019. Primary end point was the detection of neurologic dysfunctions. The secondary end point was mortality. For baseline adjustment, the propensity score matching method was used. Multivariable logistic regression analysis was performed to determine the predictor of neurologic events.

Results

Among 522 patients (aged 62.0 ± 14.9 years; 45.7% women), unilateral and bilateral ACP techniques were used in 357 (64.7%) and 165 (35.3%) patients, respectively. Transient (19.6% vs 21.2%; P = .65) and permanent (7.0% vs 10.3%; P = .70) neurologic dysfunction rates were not significantly different in patients with unilateral versus bilateral ACP, respectively. Observed mortality rate was higher in the patients with bilateral ACP (hazard ratio, 2.05; 95% CI, 1.33-3.14; P = .001). Propensity-score matching yielded 94 pairs of patients. In matched analysis, bilateral ACP did not significantly lower the risks for transient (odds ratio, 0.87; 95% CI, 0.42-1.81; P = .71) and permanent (odds ratio, 1.42; 95% CI, 0.55-3.85; P = .47) neurologic dysfunction or death (hazard ratio, 1.65; 95% CI, 0.87-3.15; P = .13). In the multivariable analysis, the ACP technique was not significantly associated with perioperative neurologic deficit.

Conclusions

Despite additional supply, the patients undergoing bilateral ACP during acute type A aortic dissection repair did not have superior outcomes in neurologic and death events compared with the patients undergoing unilateral ACP.

Unilateral or bilateral cerebral perfusion in hemiarch replacement: A prospective randomized study

BACKGROUND

We designed a prospective randomized clinical study to compare unilateral and bilateral antegrade cerebral perfusion (ACP) under moderate hypethermia in open distal aortic hemiarch replacement in ascending aortic aneurysm.

METHODS

Forty-two patients were prospectively randomized into two groups; unilateral ACP to Group 1 and bilateral ACP to Group 2. Inclusion criteria were pathological aortic aneurysm in the ascending aorta and/or aortic arch, elective operation, normal preoperative carotid Doppler ultrasonography, and nonexistence of preoperative neurological event. Patients were evaluated with preoperative and postoperative biochemical blood analysis, magnetic resonance imaging (MRI), and neurological disorders. The primary endpoints were permanent neurological disorder and death.

RESULTS

There were 21 patients in each group. Mean age was 56.57 ± 10.06 years in Group 1 and 50.95 ± 15.64 years in Group 2 (p = .170). No significant difference was found according to demographic data. ACP times were significantly higher in bilateral ACP (Group 1: 12.62 ± 5.04 min, Group 2: 18.23 ± 9.04 min, p = .018) whereas cross-clamp time and cardiopulmonary bypass times were not (p = .693 and p = .584 sequentially). Transient neurological disorder was found in seven patients in Group 1 and in 4 patients in Group 2 (p = .484). Postoperative MRI revealed new milimetric ischemic zones in three patients in Group 1 but none in Group 2. No permanent neurological disorder or mortality was seen.

CONCLUSION

The present randomized clinical prospective study could not prove the superiority of one of the technique in cerebral protection probably because, our overall ACP time was too short.

Effect of different types of cerebral perfusion for acute type A aortic dissection undergoing aortic arch procedure, unilateral versus bilateral

Background

Antegrade cerebral perfusion (ACP), including unilateral and bilateral, is most commonly used for cerebral protection in aortic surgery. There is still no consensus on the superiority of the two methods. Our research aimed to investigate the clinical effects of u-ACP and b-ACP.

Methods

321 of 356 patients with type A aortic dissection were studied retrospectively. 124 patients (38.6%) received u-ACP, and 197 patients (61.4%) received b-ACP. We compared the incidence of postoperative neurological complications and other collected data between two groups. Besides, we also analyzed perioperative variables to find the potential associated factors for neurological dysfunction (ND).

Results

For u-ACP group, 54 patients (43.5%) had postoperative neurological complications, including 22 patients (17.7%) with permanent neurologic dysfunction (PND) and 32 patients (25.8%) with temporary neurologic dysfunction (TND). For b-ACP group, 47 patients (23.8%) experienced postoperative neurological complications, including 16 patients (8.1%) of PND and 31 patients (15.7%) of TND. The incidence of PND and TND were significantly different between two groups along with shorter CPB time (p = 0.016), higher nasopharyngeal temperature (p≦0.000), shorter ventilation time (p = 0.018), and lower incidence of hypoxia (p = 0.022). Furthermore, multivariate stepwise logistic regression analysis confirmed that preoperative neurological dysfunction (OR = 1.20, p = 0.028), CPB duration (OR = 3.21, p = 0.002), and type of cerebral perfusion (OR = 1.48, p = 0.017) were strongly associated with postoperative ND.

Conclusions

In our study, it was observed that b-ACP procedure exhibited shorter CPB time, milder hypothermia, shorter ventilation time, lower incidence of postoperative hypoxia, and neurological dysfunction compared to u-ACP. Meanwhile, the incidence of ND was independently associated with three factors: preoperative neurological dysfunction, CPB time, and type of cerebral perfusion.

Double arterial cannulation strategy for acute type A aortic dissection repair: A 10-year single-institution experience

Background

Repair of acute type A aortic dissection (ATAAD) is a complex and emergent cardiovascular surgery that is associated with high perioperative morbidity and mortality. Each cannulation strategy has different benefits and drawbacks during cardiopulmonary bypass. Using a retrospective study design, we aimed to clarify the safety and efficacy of right axillary artery cannulation in combination with femoral artery cannulation compared to single arterial cannulation for ATAAD repair.

Methods

From January 2007 to July 2017, 476 adult patients underwent ATAAD repair at a single institution. Patients were classified into groups according to their cannulation strategy: the double arterial cannulation (DAC) group (n = 377; 79.2%) or single arterial cannulation (SAC) group (n = 99; 20.8%). Preoperative demographics, surgical information, and postoperative recovery were compared between both groups. Survival and freedom from reoperation rates were analyzed using the Kaplan-Meier actuarial method.

Results

Demographics, comorbidities, and surgical procedures were generally homogenous between the two groups, except for sex, age, and rate of extensive aortic repair. Patients who underwent DAC had lower in-hospital mortality (13.5% vs. 25.3%; P = 0.005) and lower incidence of malperfusion-related complications (18.8% vs. 30.3%; P = 0.011) than those who underwent SAC. During multivariate analysis, SAC was identified as an in-hospital mortality predictor (odds ratio, 2.81; 95% confidence interval, 1.52–5.17; P = 0.001), as were preoperative ventilator support, intraoperative extracorporeal membrane oxygenation installation, and postoperative malperfusion-related complications. Three-year cumulative survival and freedom from reoperation rates were 74.8% and 85.3% for the DAC group and 62.6% and 81.1% for the SAC group, respectively (P = 0.010 and 0.430, respectively).

Conclusions

With acceptable short- and mid-term outcomes, DAC is effective and safe for establishing cardiopulmonary bypass during ATAAD repair.

Open repair techniques in the aortic arch are still superior

Conventional arch replacement can be carried out in a great majority of patients. Hybrid procedures are often as invasive and technically difficult as conventional ones. Moreover, their immediate results are, in many reported experiences, not better and their long-term results less favourable than the ones observed with conventional methods. So, yes, the open conventional arch replacement is still "the gold standard".

Bilateral versus unilateral antegrade cerebral perfusion in total arch replacement for type A aortic dissection

BACKGROUND

Antegrade cerebral perfusion (ACP) is the most widely used cerebral protection strategy for complex aortic repair and includes unilateral (u-ACP) and bilateral (b-ACP) techniques. The superiority of b-ACP over u-ACP has been the subject of much debate. Focusing on type A aortic dissection requiring total arch replacement, we investigated the clinical effects of b-ACP versus u-ACP.

METHODS

Between September 2006 and August 2014, 203 patients presenting with type A aortic dissection (median age, 51.0 ± 13 years; range, 17-72 years; 128 males) underwent total aortic arch replacement with hypothermic circulatory arrest. ACP was used in all patients, including u-ACP in 82 (40.3%) and b-ACP in 121 (59.7%).

RESULTS

There was no significant difference between the u-ACP and b-ACP groups in terms of cardiopulmonary bypass (CPB) time, cross-clamp time, or circulatory arrest time. Overall 30-day mortality was comparable in the 2 groups (11.6% for b-ACP vs 20.7% for u-ACP; P = .075). The prevalence of postoperative permanent neurologic dysfunction (PND) was comparable as well (8.4% vs 16.9%; P = .091). Mean ventilation time was lower in the b-ACP group (95.5 ± 45.25 hours vs 147.0 ± 82 hours; P < .001). Mean lengths of stay in the intensive care unit and the hospital overall were comparable in the 2 groups (intensive care unit: 16 ± 17.75 days vs 17 ± 11.5 days, P = .454; hospital: 26.5 ± 20.6 days vs 24.8 ± 10.3 days, P = .434). The P values from logistic regression models indicated that in the 2 groups combined, CPB time and circulatory arrest time were independent risk factors for both mortality and PND.

CONCLUSIONS

In this, the first published study focusing on the efficacy of u-ACP and b-ACP in total arch replacement for type A aortic dissection, the b-ACP group did not demonstrate significantly lower 30-day mortality or PND rate compared with the u-ACP group. Future large-sample studies are warranted to thoroughly examine this critical issue.

The neurologic protection of unilateral versus bilateral antegrade cerebral perfusion in aortic arch surgery with deep hypothermic circulatory arrest: A study of 77 cases

BACKGROUD

Unilateral and bilateral antegrade cerebral perfusions (ACP) are recognized methods of cerebral protection in aortic arch surgery. However, the adequacy of cerebral protection in aortic arch surgery with deep hypothermic circulatory arrest is controversial. In this study, we compared unilateral and bilateral ACP of cerebral protection in aortic arch surgery by assessing the patient's intraoperative and postoperative brain function.

METHODS

A total of 77 patients undergoing aortic arch surgery were included in this study. Unilateral ACP was performed using a cannula in the innominate artery (n = 40), whereas bilateral ACP was conducted using an additional cannula in the left carotid artery (n = 37). Levels of S-100β and neuron specific enolase (NSE) were assayed at the beginning of cardiopulmonary bypass (T1), the beginning of circulatory arrest (T2), and post ACP at T = 25 min (T3), the end of ACP (T4), the end of cardiopulmonary bypass (T5), and at T = 1 h (T6), T = 6 h (T7), and T = 24 h (T8). Transcranial Doppler ultrasonography was used both preoperatively and intraoperatively to detect the blood flow of bilateral middle cerebral artery (MCA), and neurologic deficit incidence and mortality rates were obtained.

RESULTS

At time points T1, T2, and T3, plasma levels of S-100β and NSE were not statistically different between groups. However, S-100β and NSE levels for each time point ranging from T = T4 to T = T8 did show statistically significant differences between groups. Patients who with one side of the middle cerebral artery stenosis, used bilateral antegrade cerebral perfusions method, intraoperative Transcranial Doppler ultrasonography examination showed narrow side blood flow weaker than the normal side during the deep hypothermic circulatory arrest (DHCA), however no significant differences could be observed between the two sides (P > 0.05). The incidence of neurological dysfunction was higher in the unilateral ACP group compared to the bilateral ACP group (25% vs. 8.11%, respectively, P = 0.028). Moreover, no marked differences were observed in mortality (2.5% vs. 5.41%, respectively, P = 1.000).

CONCLUSIONS

When the duration of DHCA was 25 min or less, no significant differences were observed between unilateral and bilateral ACP. However, when DHCA exceeded 25 min, bilateral ACP was more effective compared to unilateral ACP. Due to the high variations in circle of Willis as well as increased safety, simplicity, and efficiency, the bilateral ACP approach is preferred over the unilateral technique.

A Clinical Protocol for Goal Directed Cerebral Perfusion during Aortic Arch Surgery

OBJECTIVE

The optimal strategy to deliver antegrade cerebral perfusion for cerebral protection during hypothermic circulatory arrest has not been established. The purpose of this review was to present our current clinical protocol utilizing selective antegrade cerebral perfusion during aortic arch surgery and to compare it to other published experience.

CLINICAL PROTOCOL

Since 2013, our clinical protocol for aortic arch surgery has evolved to using selective antegrade cerebral perfusion via the innominate artery, moderate hypothermia, and ancillary strategies such as goal-directed perfusion (GDP). Other published techniques favored antegrade cerebral perfusion but were limited by smaller cannulae, multiple cannulation sites, and lower cooling temperatures.

CONCLUSION

Our clinical protocol may offer higher flow rates, avoid complications associated with additional cannulae, and provide an easy setup for dual arterial perfusion. Additionally, GDP has enhanced our understanding of metabolic physiology and may facilitate the development of a better cerebral protection strategy.

Ascending Aortic Repair and Simultaneous Femoro-Femoral Crossover Bypass for Acute DeBakey Type I Dissection with Leg Ischemia

A 61-year-old man was admitted with acute Type A aortic dissection DeBakey Type I with clinical and radiographic signs of left iliac artery occlusion and leg ischemia. He underwent simultaneous ascending aortic repair and surgical femoro-femoral crossover bypass with immediate restoration of leg perfusion as assessed with peripheral near-infrared spectroscopy. The postoperative course was uneventful. Follow-up computed tomography demonstrated occlusion of the left external iliac artery and patent crossover bypass.

How to Perfuse: Concepts of Cerebral Protection during Arch Replacement

Arch surgery remains undoubtedly among the most technically and strategically challenging endeavors in cardiovascular surgery. Surgical interventions of thoracic aneurysms involving the aortic arch require complete circulatory arrest in deep hypothermia (DHCA) or elaborate cerebral perfusion strategies with varying degrees of hypothermia to achieve satisfactory protection of the brain from ischemic insults, that is, unilateral/bilateral antegrade cerebral perfusion (ACP) and retrograde cerebral perfusion (RCP). Despite sophisticated and increasingly individualized surgical approaches for complex aortic pathologies, there remains a lack of consensus regarding the optimal method of cerebral protection and circulatory management during the time of arch exclusion. Many recent studies argue in favor of ACP with various degrees of hypothermic arrest during arch reconstruction and its advantages have been widely demonstrated. In fact ACP with more moderate degrees of hypothermia represents a paradigm shift in the cardiac surgery community and is widely adopted as an emergent strategy; however, many centers continue to report good results using other perfusion strategies. Amidst this important discussion we review currently available surgical strategies of cerebral protection management and compare the results of recent European multicenter and single-center data.

Acute aortic dissection type A

Background

Acute aortic dissection type A (AADA) is a life-threatening vascular emergency. Clinical presentation ranges from pain related to the acute event, collapse due to aortic rupture or pericardial tamponade, or manifestations of organ or limb ischaemia. The purpose of this review was to clarify important clinical issues of AADA management, with a focus on diagnostic and therapeutic challenges.

Methods

Based on a MEDLINE search the latest literature on this topic was reviewed. Results from the German Registry for Acute Aortic Dissection Type A (GERAADA) are also described.

Results

Currently, the perioperative mortality rate of AADA is below 20 per cent, the rate of definitive postoperative neurological impairment approaches 12 per cent and the long-term prognosis after surviving the acute phase of the disease is good. Many pathology- and therapy-associated factors influence the outcome of AADA, including prompt diagnosis with computed tomography and better cerebral protection strategies during aortic arch reconstruction. Endovascular technologies are emerging that may lead to less invasive treatment options.

Conclusion

AADA is an emergency that can present with a wide variety of clinical scenarios. Advances in the surgical management of this complex disease are improving outcomes.

Brief review on systematic hypothermia for the protection of central nervous system during aortic arch surgery: a double-sword tool?

Antegrade selective cerebral perfusion in conjunction with hypothermia attenuate postoperative neurological injury, which in turn still remains the main cause of mortality and morbidity following aortic arch surgery. Hypothermic circulatory arrest however could be a useful tool during arch surgery, surgery for chronic thromboembolic disease, air on the arterial line during CPB, during cavotomy for extraction of renal cell carcinoma with level IV extension, or when dealing with difficult trauma to the SVC or IVC. Cerebral protective effects with hypothermic procedures including inhibition of neuron excitation, and discharge of excitable amino acids, and thereby, prevention of an increase in intercellular calcium ions, hyperoxidation of lipids in cell membranes, and free radical production.The authors are briefly discussing the fundamental principles of using hypothermia as an adjunct tool of the cardiothoracic surgeon's practice. The relationship between temperature, flow, metabolic requirements and adverse effects is addressed.

Deep hypothermic circulatory arrest: Alternative strategies for cerebral perfusion. A review article

Deep hypothermic circulatory arrest is an essential tool in the surgeon’s armamentarium. There are essentially three strategies to address cerebral ischemia during arrest periods. Early surgical case series pioneered the option of complete anoxia with deep hypothermia. Subsequent innovators introduced the concept of retrograde perfusion of the cerebral vessels through the venous system, and others have advocated the use of selective and non-selective antegrade perfusion of the cerebral arteries. Clinical studies assessing outcomes of the three approaches are compromised by small patient numbers, retrospective design and surgeon bias.

In this review, the authors will briefly discuss the conceptual basis of these strategies and the literature comparing these approaches in terms of key neurologic outcomes. The importance of this topic will emphasize the key role the perfusion community plays in establishing guidelines for best practice in circulatory arrest to go forward with education and research in this area.

Clinical Results of Ascending Aorta and Aortic Arch Replacement under Moderate Hypothermia with Right Brachial and Femoral Artery Perfusion

Background

Selective antegrade perfusion via axillary artery cannulation along with circulatory arrest under deep hypothermia has became a recent trend for performing surgery on the ascending aorta and aortic arch and when direct aortic cannulation is not feasible. The authors of this study tried using moderate hypothermia with right brachial and femoral artery perfusion to complement the pitfalls of single axillary artery cannulation and deep hypothermia.

Materials and Methods

A retrospective analysis was performed on 36 patients who received ascending aorta or aortic arch replacement between July 2005 and May 2010. The adverse outcomes included operative mortality, permanent neurologic dysfunction and temporary neurologic dysfunction.

Results

Of these 36 patients, 32 (88%) were treated as emergencies. The mean age of the patients was 61.9 years (ranging from 29 to 79 years) and there were 19 males and 17 females. The principal diagnoses for the operation were acute type A aortic dissection (31, 86%) and aneurysmal disease without aortic dissection (5, 14%). The performed operations were ascending aorta replacement (9, 25%), ascending aorta and hemiarch replacement (13, 36%), ascending aorta and total arch replacement (13, 36%) and total arch replacement only (1, 3%). The mean cardiopulmonary bypass time was 209.4±85.1 minutes, and the circulatory arrest with selective antegrade perfusion time was 36.1±24.2 minutes. The lowest core temperature was 24±2.1℃. There were five deaths within 30 post-op days (mortality: 13.8%). Two patients (5.5%) had minor neurologic dysfunction and six patients, including three patients who had preoperative cerebral infarction or unconsciousness, had major neurologic dysfunction (16.6%).

Conclusion

When direct aortic cannulation is not feasible for ascending aorta and aortic arch replacement, the right brachial and femoral artery can be used as arterial perfusion routes with the patient under moderate hypothermia. This technique resulted in acceptable outcomes.

Cerebral protection during surgery of the aortic arch

Brain injury represents a primary concern during aortic arch surgery. Valid surgical techniques and reliable methods of brain protection are required to obtain a favorable outcome after such a complex surgery. Our aim was to review available methods of brain protection including deep hypothermia and circulatory arrest, retrograde cerebral perfusion and antegrade cerebral perfusion.

What is the best method for brain protection in surgery of the aortic arch? Selective antegrade cerebral perfusion

Despite considerable progress in the operative management of lesions involving the transverse aortic arch, replacement of this portion of the vessel remains a surgical challenge and is still associated with mortality and morbidity. This situation is due not only to the technical difficulties of the procedure but, often, to the unsatisfactory preservation of the integrity of the central nervous system during the period of arch exclusion. The techniques of cerebral protection during surgery of the aortic arch can be divided into those aimed at suppressing the metabolic demand of the central nervous system and those aimed at maintaining the metabolic supply during the time of exclusion of the cerebral vessels. Whichever technique is used, it must maintain the normal metabolism of the central nervous system or, at least, allow restoration of the physiologic conditions of its function. In this regard, selective antegrade cerebral perfusion has demonstrated experimentally and clinically its superiority over the other proposed protective techniques.

Central Nervous System Protection in Cardiac Surgery

Neurological dysfunction and stroke following cardiac surgery and thoracic surgery requiring hypothermic circulatory arrest is a well-defined problem. The original studies in CABG patients identified risk factors, such as prior stroke and lower educational level. There is older evidence suggesting that higher perfusion pressures during cardiopulmonary bypass are helpful. Hyperthermia during rewarming on cardiopulmonary bypass and postoperative hyperthermia have been associated with adverse cognitive outcomes. Glucose management intraoperatively remains controversial, but most now advocate for moderate glucose control using insulin, if required. The subset of patients having thoracic aortic surgery requiring periods of aortic discontinuity are particularly problematic. A cerebral protection strategy should be determined, and this may include hypothermic circulatory arrest, selective cerebral perfusion, or retrograde cerebral perfusion. All of these techniques have been associated with good surgical outcomes, but there is little information on cognitive outcomes of thoracic aortic surgery.

Initial experience of an arterial shunt for bilateral antegrade cerebral perfusion during hypothermic circulatory arrest

PURPOSE

The purpose of this study is to describe an intravessel cerebral shunt that allows perfusion of both cerebral hemispheres through the axillary artery.

DESCRIPTION

The cerebral shunt is a 10-cm to 12-cm long cannula with a lumen for blood perfusion and two balloons, one at each distal end. The proximal balloon is adapted for retaining the proximal end of the catheter in the innominate artery; the second inflatable balloon is adapted for retaining the distal end of the catheter into the left common carotid artery.

EVALUATION

Three consecutive patients received bilateral brain perfusion through the right axillary artery with the use of this cerebral shunt.

CONCLUSIONS

The cerebral shunt allowed bilateral cerebral perfusion as verified with cerebral oximetry in the absence of any evident neurologic dysfunction.

Central cannulation is safe in acute aortic dissection repair

OBJECTIVE

The site of cannulation for the repair of ascending aortic dissection remains controversial. It is not clear whether cannulation of the dissected vessel is safe or even preferred. We hypothesized that cannulation of the dissected aorta could be done safely with acceptable complication and mortality rates in this high-risk population.

METHODS

The charts of repairs of acute ascending aortic dissections (n = 70) from 1996 to 2005 were reviewed. Cannulation was accomplished in 24 patients via the dissected aorta (central) and in 46 patients through cannulation of the femoral or axillary artery (peripheral). All were converted to sidearm cannulation of the graft for reperfusion. Groups were compared on the basis of comorbidities in addition to mortality, complications, hospital stays and final disposition.

RESULTS

The groups were comparable on the basis of age and preoperative comorbidities. Similarly, there were no differences in bypass time, crossclamp time, or hypothermic circulatory arrest time between groups. Hospital mortality and postoperative complications, including stroke, were similar between groups, but the peripheral group experienced more cardiac events (peripheral 15% vs central 0%; P < .05) and higher mortality than the central group (peripheral 19.5% vs central 4.2%; P < .05).

CONCLUSIONS

Direct cannulation of the dissected aorta was safe compared with peripheral cannulation in these patients. Inasmuch as these data demonstrate that cannulation of the dissected ascending aorta is safe, this technique can be used to tailor the cannulation approach to specific anatomic and patient characteristics that might optimize postoperative outcomes in this disease entity.