Reattachment Of Intercostal Arteries Research Articles

Intercostal artery reattachment for prevention of spinal cord ischaemia.

Intercostal artery reattachment for prevention of spinal cord ischaemia.

Open thoracoabdominal aortic aneurysm surgery technique: how we do it.

More than four decades have passed since the modern principals to treat thoracoabdominal aortic aneurysm (TAAA) have been established. The historical challenges in repair of TAAA are represented by - and continue to be - multiorgan protection. Among all organs, the spinal cord remains one of the most vital and vulnerable. We described our current techniques of open extent II TAAA repair, including the following topics: anesthesia, intraoperative monitoring, skin incision, exposure of the TAAA, left heart bypass, graft replacement technique, intercostal artery reattachment, visceral/renal artery reconstructions, and postoperative care. We use cerebrospinal fluid drainage, distal aortic perfusion, mild passive hypothermia, sequential clamping, and visceral and renal perfusion using roller pump in all the cases for multiorgan protection. Both motor-evoked potentials and somatosensory-evoked potentials ere used to guide the conduct of intercostal artery reattachment. Our group demonstrated that the use of adjuncts has reduced the overall spinal cord ischemia rate after Extent I TAAA from 15% to less than 2% and after Extent II TAAA from 33% (50% with clamp time exceeding 40 minutes in "clamp and go" era) to less than 4%. The current standard practice of TAAA repair with adjuncts has improved outcomes, especially regarding spinal cord ischemia.

Intercostal artery incorporation to prevent spinal cord ischemia during total endovascular thoracoabdominal aortic repair

Spinal cord ischemia (SCI) is a devastating complication of aortic repair with multiple strategies developed specifically to prevent and mitigate its occurrence by preserving spinal cord perfusion. This includes permissive hypertension, limiting endovascular aortic coverage, reattachment of intercostal arteries during open repair, steroid infusion, and spinal fluid drainage.1-4

Spinal Cord Deficit After 1114 Extent II Open Thoracoabdominal Aortic Aneurysm Repairs

A single-institution retrospective review was performed between 1991 and 2017. Of 1114 patients who underwent type II thoracoabdominal aortic aneurysm (TAAA) repair, intercostal lumbar artery reattachment was used in 86% (959) of cases and cerebrospinal fluid drainage in 63% (698). Spinal cord deficit developed after 14% (151) of repairs (8% [86] permanent). Patients with spinal cord deficit were more likely to present with rupture and to undergo emergency repair. Reattachment of intercostal arteries was protective against paraplegia or paraparesis. Spinal cord deficits after type II TAAA repair remain concerning.

Early and late outcomes of open repair for dissecting aneurysms of the descending or thoraco-abdominal aorta.

Although open repair is the standard surgical option for dissecting descending thoracic aneurysms (DTAs) and thoraco-abdominal aorta aneurysms (TAAAs), it remains a significant challenge with considerable perioperative morbidity and mortality. We retrospectively analysed early and late outcomes of open repair for these aortic aneurysms. Early and late outcomes were investigated for 223 consecutive patients who underwent open repair for dissecting DTA or TAAA between January 2003 and December 2014 (mean age 55 ± 16 years). The basic strategy for open surgery comprised liberal use of deep hypothermia and aggressive preservation or reattachment of intercostal arteries, i.e. donor arteries for the artery of Adamkiewicz. Deep hypothermia was used in 150 (67.3%) patients. The overall in-hospital mortality rate was 3.6% and 1.5% for elective cases. The rates of spinal cord ischaemic injury and stroke were 3.1% and 4.5%, respectively. During follow-up (mean 63 ± 40 months), overall 5-year survival rates was 89.2 ± 2.4% and 91.3 ± 2.8% and 86.3 ± 4.1% for DTA and TAAA, respectively. Five- and 10-year rates of freedom from aortic events, defined as surgery for initial operation-related events or for downstream aortic dilation, were 89.1 ± 3.5% and 68.2 ± 7.8% for DTA and 100% and 96.6 ± 3.4% for TAAA, respectively (P < 0.01). Our approach in treating this aortic pathology showed favourable early and long-term outcomes with acceptable neurological complication rates. More careful follow-up is necessary in patients with DTA repair, because downstream aortic enlargement occurs in some patients.

Embolism is emerging as a major cause of spinal cord injury after descending and thoracoabdominal aortic repair with a contemporary approach: magnetic resonance findings of spinal cord injury.

We reviewed magnetic resonance (MR) findings of the spinal cord in patients who had a spinal cord injury after descending and thoracoabdominal aortic repair, to speculate the specific cause of the injury. Between 2000 and 2012, 746 patients underwent descending or thoracoabdominal aortic surgery: 480 received an open repair with adjuncts of spinal cord protection [distal perfusion, cerebrospinal fluid (CSF) drainage, reattachment of intercostal arteries and hypothermia] and 266 received an endovascular repair. Twenty-six (3.5%) suffered a spinal cord injury. Of these, 18 (14 open repair and 4 endovascular repair) underwent postoperative spinal cord MRI. Preoperative identification of the Adamkiewicz artery (ARM) was obtained in all patients except 1. Aortic pathology was dissection in 2 and non-dissection in 16 patients. There were 3 types MRI finding: sporadic infarction involving a range of spinal cord (sporadic); focal and asymmetrical infarction within a few segments of vertebra (focal); and diffuse and symmetrical infarction around the level of the ARM (diffuse). In endovascular repair, sporadic infarction was observed in all patients (4 of 4). In open repair, sporadic infarction was observed in 3 (21%), focal infarction in 7 (50%) and diffuse infarction in 4 (29%). In all patients who had sporadic or focal infarction, the aortic pathology was non-dissection. From these findings, embolism is 1 of the major causes of spinal cord injury in the era of adjuncts to optimize spinal cord haemodynamics during aortic repair.

Elective sac perfusion to reduce the risk of neurologic events following endovascular repair of thoracoabdominal aneurysms

Spinal cord ischemia (SCI) is a catastrophic complication of thoracoabdominal aortic aneurysm (TAAA) repair. This article describes our early experience with a technique for maintaining perfusion of segmental vessels (intercostals and lumbars) in the early postoperative period after endovascular repair of a TAAA, with "sac perfusion branches" added to custom-made stent grafts. These are closed 7 to 10 days after the first procedure to complete exclusion of the aneurysm. We have used this technique in 10 patients with type II TAAAs. One developed monoparesis of the right leg during a period of hypotension secondary to a cardiac event and died within 30 days. Two patients developed lower limb weakness after closure of the perfusion branches, both with full recovery. Controlled perfusion of segmental vessels with perfusion branches is feasible and may be a useful adjunct to prevent SCI, providing protection to spinal cord perfusion during the immediate postoperative period when risk of SCI is greatest.

Paraplegia prevention branches: A new adjunct for preventing or treating spinal cord injury after endovascular repair of thoracoabdominal aneurysms

In this report, we describe a technique that could potentially be used for both prevention and treatment of spinal cord ischemia (SCI) in endovascular repair of thoracoabdominal aneurysms. This technique involves using a specially designed endograft with side branches (paraplegia prevention branches [PPBs]), which are left patent to perfuse the aneurysmal sac and any associated lumbar or intercostal arteries in the early postoperative period. The use of PPBs with this technique is feasible and allows for a temporary controlled endoleak that may be useful for preventing or reversing spinal cord injury. This technique may be considered as an adjunct to the more standard perioperative physiological manipulations such as permissive hypertension and spinal fluid drainage.

Pro: It Is Safe to Proceed With Thoracoabdominal Aortic Aneurysm Surgery After Encountering a Bloody Tap During Cerebrospinal Fluid Catheter Placement

URING THE PAST 20 years, major advances in the intraoperative management of patients undergoing thoracoabdominal aortic aneurysm (TAAA) surgery have substantially reduced postoperative primary morbidity and mortality. At present, mortality rates after TAAA repair are estimated to be 5% to 10%, neurologic deficits 3% to 10%, renal failure 8% to 29%, and pulmonary complications 30% to 40%.1-4 Among the most feared complications of thoracic aortic aneurysm (TAA) and TAAA surgery are paraparesis and paraplegia, which are estimated to occur in 6% to 10% of patients who undergo TAA or TAAA repair. 5,6 Patients with these complications have a 20% greater risk of mortality than do patients without postoperative paraparesis or paraplegia. These patients, who are usually older, require intensive rehabilitation. A patient’s risk of postoperative paraparesis and paraplegia is determined by aneurysmal extent, acute dissection, cross-clamp time, preoperative renal dysfunction, previous aortic surgery, diabetes, and rupture.7 Improvements in TAAA repair procedures, including reduced cross-clamp time, distal aortic perfusion, and reattachment of intercostal arteries, have minimized critical ischemic times. Adjuncts such as cerebrospinal fluid (CSF) drainage, spinal cord monitoring, atrial femoral bypass, regional and systemic cooling, intrathecal papaverine, intraoperative use of naloxone, steroids and barbiturates, and the recognition and treatment of factors related to coagulopathy, have also been introduced. 8 The arterial circulation of the spinal cord consists of 2 interconnected sources: intrinsic and extrinsic. The intrinsic blood supply consists of a single anterior spinal artery (ASA), which courses along the ventral aspect of the cord and ultimately supplies the bulk of the cord substance through penetrating arteries, and paired posterior spinal arteries, which supply the remainder of the cord. This intrinsic circulation in turn receives its extrinsic blood supply via the radiculomedullary arteries, although the anatomic details of this supply vary among individuals. The principal extrinsic blood supply in the cervical and upper thoracic region comes from branches of the vertebral arteries; the thoracolumbar cord is supplied by intercostal and lumbar arteries, and the conus is supplied by the lateral sacral branches of the hypogastric vessels. There are 2 aspects of the spinal cord circulation that explain the risk of cord ischemia during TAAA repair. First, the diameter and continuity of the ASA vary along its length. Angiographic studies have shown that the ASA becomes extremely narrow cephalad to its anastomosis with the great radicular artery. Second, the human spinal cord is irregularly supplied by the radiculomedullary arteries because only few of them actually reach the cord substance. The thoracolumbar region is at the most risk for ischemic injury because this region is typically supplied by a single radiculomedullary artery, better known as the artery of Adamkiewicz or arteria radicularis magna. This artery has been shown to arise from T9 to T12 in about 75% of individuals. Because this area falls within the segment of the aorta that is clamped during reconstruction, clamping can compromise the blood supply to the cord. With proximal descending aortic cross-clamping, adequate spinal cord perfusion requires ASA patency, collateral circulation, and sufficient spinal cord perfusion pressure, defined as the difference between spinal artery pressure and CSF pressure. 9 During hypoxia and hypercarbia, autoregulation of spinal cord blood flow is lost and flow becomes linearly related to perfusion pressure. For this reason, adjuncts that decrease CSF pressure will increase spinal cord perfusion pressure. The rationale for using a CSF drain is based on experimental data showing that (1) CSF pressure increases during aortic clamping and (2) reducing CSF pressure improves spinal perfusion. Drenger et al 10 observed acute increases in CSF pressure immediately after applying the aortic clamp during TAAA repair. These increases were similar in patients with and without distal bypass and have been attributed to a sudden elevation of cerebral blood flow. The authors also observed a second peak

“Cobrahead” graft for intercostal artery implantation during descending aortic replacement

A technique for a separate sidearm graft (“cobrahead”) to facilitate reattachment of intercostal arteries in descending aortic replacement is described. The technique allows for very prompt restoration of spinal cord blood flow (via a Y attachment from the arterial perfusion circuit). The technique permits a simple, quick, and fully accessible anastomosis, technically more facile than the traditional side-to-side anastomosis. None of 7 patients treated with this technique had early or late paraplegia. Preliminary computed tomographic follow-up scans confirm patency of the cobrahead graft.

Benefits of Monitoring Motor-Evoked Potentials during Thoracoabdominal Aortic Aneurysm Repair: Technique of Choice to Assess Spinal Cord Ischemia?

Spinal cord ischemic injury following thoracoabdominal aortic aneurysm (TAAA) repair remains the most devastating complication, which still occurs in 10 to 30°I° of patients, despite protective measures such as distal aortic perfusion, cerebrospinal fluid (CSF) drainage, epidural cooling, and reattachment of intercostal arteries. One of the most important limitations of protective actions is the inability to assess the adequacy of spinal cord perfusion and cord function. We developed a technique to record motor-evoked potentials (MEPs) during thoracoabdominal aortic surgery to assess spinal cord ischemia and evaluate the subsequent protective strategies to prevent neurological deficit. Furthermore, a subpopulation was simultaneously monitored with somatosensory evoked potentials (SSEPs). The surgical protocol included left heart bypass and CSF drainage. When spinal cord ischemia was detected, distal aortic pressure and mean arterial pressure were increased. By means of sequential crossclamping, MEPs were ...

Strategies to prevent neurologic deficit based on motor-evoked potentials in type I and II thoracoabdominal aortic aneurysm repair

Purpose: Motor-evoked potentials (MEPs) were monitored during thoracoabdominal aortic aneurysm (TAAA) repair to assess spinal cord ischemia and evaluate the subsequent protective strategies to prevent neurologic deficit. Methods: Between January 1996 and December 1997, 52 consecutive patients with type I (n = 24) and type II (n = 28) TAAA underwent surgery (mean patient age, 60 years; range, 21–78 years). The surgical protocol included left heart bypass, cerebrospinal fluid drainage, and monitoring transcranial myogenic MEPs. When spinal cord ischemia was detected, distal aortic pressure and mean arterial pressure were increased. By means of sequential crossclamping, MEPs were used to identify critical intercostal or lumbar arteries. Results: Reproducible MEPs could be recorded in all patients, and spinal cord ischemia was detected within 2 minutes. During distal aortic perfusion, 14 patients (27%) showed rapid decrease in the amplitude of MEPs to less than 25% of baseline, indicating spinal cord ischemia, which could be corrected by increasing distal aortic pressure. The mean distal aortic pressure to maintain adequate cord perfusion was 66 mm Hg; however, it varied among individuals between 48 and 110 mm Hg. In 24 patients (46%), MEPs disappeared after segmental clamping and returned after reattachment of intercostal arteries. In 9 patients (17%), MEPs disappeared completely, but no intercostal arteries were found. After aortic endarterectomy, 6 or 8 mm Dacron grafts were anastomosed to intercostal arteries, and MEPs returned after reperfusion. Using this aggressive surgical approach based on MEPs, no early or late paraplegia occurred in this series. Conclusion: Monitoring of MEPs is an effective technique to assess spinal cord ischemia. Operative strategies based on MEPs prevented neurologic deficits in patients treated for type I and II TAAA. (J Vasc Surg 1999;29:48-59.)

Reduced renal failure following thoracoabdominal aortic aneurysm repair by selective perfusion.

Renal failure and visceral ischemia are feared complications following thoracoabdominal aortic aneurysm (TAAA) repair, significantly contributing to mortality. This prospective study describes volume- and pressure-controlled perfusion of the renal and visceral arteries during TAAA surgery. In 73 consecutive patients (mean age 59 years), TAAA repair (27 type I, 28 type II, 8 type III and 10 type IV) was performed, using retrograde and selective organ perfusion. Sixteen patients had impaired renal function with blood creatinine higher than 100 mmol/l. During the thoracic part of the procedure, the mean distal aortic pressure was kept above 60 mm Hg by means of left-heart bypass. After opening the abdominal aorta, the renal and visceral arteries were individually perfused by means of perfusion catheters (9 French) in the first 33 patients (group I). Volume flow through each catheter was assessed with ultrasound flow meters and maintained at least at 60 ml/min. In addition to volume flow measurements, catheters with pressure sensors were used in the last 40 patients (group II), allowing pressure-controlled selective perfusion. The extent of the aneurysm was comparable in both groups. Mean cross-clamp time for the thoracic part was 46 min, including proximal anastomosis and reattachment of intercostal arteries. Mean cross-clamp time for the abdominal part was 74 min, including re-implantation of intestinal and renal arteries and selective dacron grafts to the celiac-axis arteries (n = 5), superior mesenteric arteries (n = 8) and renal arteries (n = 25), through which the catheters guaranteed continuous perfusion during the time the anastomosis was performed. Urine output was uninterrupted in all patients, irrespective of cross-clamp time. In group I, one patient (3%) developed renal failure and three patients (9%) required temporary peritoneal dialysis. In group II, no patients developed renal failure and two patients (5%) required temporary peritoneal dialysis. Thirteen patients with pre-existing renal impairment did not deteriorate. No patients developed visceral ischemia or multiple-organ failure. Total in-hospital mortality was 6/73 (8%) and was related to cardiopulmonary complications. Renal and visceral ischemia can be reduced significantly by continuous perfusion during cross-clamping in TAAA repair. Not only sufficient volume flow but also adequate arterial pressure appears to be essential in maintaining renal function.

Importance of intercostal artery reattachment during thoracoabdominal aortic aneurysm repair

Purpose: We studied the relationship of neurologic deficit to ligation, reimplantation, and preexisting occlusion of intercostal arteries to determine which arteries and consequent management are most critical to outcome in thoracoabdominal aortic aneurysm repair. Methods: From February 1991 to July 1996, 343 patients with thoracoabdominal aortic aneurysms underwent repair by one surgeon. In this study, only Crawford types I, II, and III (n = 264) were considered. Of these, 110 (42%) were type I, 116 (44%) type II, and 38 (14%) type III. The adjuncts of distal aortic perfusion and cerebrospinal fluid drainage were used in 164 patients (62%). Data were analyzed by contingency table and by multiple logistic regression. Results: Early neurologic deficit occurred in 23 patients (8.7%), and late deficit in 10 patients (3.8%). Neurologic deficit in patients with at least one reimplantation and no ligation of arteries T11 or T12 occurred in 19 of 147 (12.9%). Neurologic deficit for occlusion of the same arteries occurred in 11 of 111 (9.9%), whereas for ligation of T11 and T12 neurologic deficit occurred in three of six (50%; reimplantation, p < 0.03; occlusion, p < 0.006). In addition, reimplantation of intercostal arteries T9 or T10 was significantly associated with reduced late neurologic deficit in multivariate analysis ( p = 0.05). No other intercostal artery status was associated with modification of the neurologic deficit rate. Multivariate analysis showed type II aneurysms and acute dissections to be significantly associated with an increased risk of postoperative neurologic deficit ( p < 0.0009, 0.002, respectively). Adjuncts were protective ( p < 0.007), most often in types II and III (14.1% neurologic deficit in type II with adjunct, 35.3% without; 0% in type III with adjunct, 20% without). Conclusions: Patients with patent arteries at the T11/T12 level have highly variable outcomes depending on whether the arteries are reattached or ligated. Our data suggest that reimplantation of thoracic intercostal arteries T11 and T12 is indicated when these arteries are patent. Reimplantation of T9 and T10 lowers the risk of late neurologic deficit, probably by decreasing the spinal cord's vulnerability to changes in blood and cerebrospinal fluid pressure in the days after surgery. Adjuncts lower overall risk and provide adequate time for targeted intercostal artery reimplantation. (J Vasc Surg 1998;27:58-68.)

Paraplegia After Thoracoabdominal Aortic Aneurysm Repair: Is Dissection a Risk Factor?

Background. The association between aortic dissection and paraplegia or paraparesis (P/P) after thoracoabdominal aortic aneurysm repair is not clear. Methods. Six hundred sixty patients underwent thoracoabdominal aortic aneurysm repair from 1986 through 1995 using selective atriodistal bypass, liberal reattachment of critical intercostal arteries, moderate heparinization, and permissive mild hypothermia. Dissection was present in 163 patients (24.7%) and absent in 497 (75.3%). Results. Early mortality occurred in 7.4% overall, and did not differ between patients with nondissection, acute dissection, or chronic dissection. The incidence of P/P was 5.4% overall, 5.5% without dissection, and 5.0% with dissection. The risk of P/P for acute versus chronic dissection was 19% versus 2.9%, respectively ( p = 0.011). Rupture and Crawford extent II were predictive of the development of P/P. In patients at high risk for P/P (ie, Crawford extent I or II), atriodistal bypass reduced the intercostal artery ischemic time, and reattachment of critical intercostal arteries (T8 to L1) reduced the incidence of P/P. Conclusions. Acute dissection increases the risk of P/P after thoracoabdominal aortic aneurysm repair; using contemporary methods, however, chronic dissection does not increase the risk of postoperative P/P. Critical intercostal artery reattachment and atriodistal bypass are beneficial in patients undergoing extensive repairs.