- Email: [email protected]
Surgical Management of Abdominal Aortic Aneurysms: A Lost Art?
P R O G RE S S I N CA RDI O V A S CU L A R D I SE A S E S 5 6 ( 2 0 13 ) 1 3–1 8
Available online at www.sciencedirect.com
ScienceDirect www.onlinepcd.com
Surgical Management of Abdominal Aortic Aneurysms: A Lost Art? Abdulhameed Aziz, Gregorio A. Sicard⁎ Section of Vascular Surgery, Department of Surgery, Washington University in St. Louis School of Medicine, St. Louis, MO A R T I C LE I N F O
AB ST R A C T
Keywords:
Endovascular repair of abdominal aneurysms has become the dominant treatment
Aorta
modality for infrarenal aneurysms. Initial reports showed a constant number of open
Aneurysms
repairs although there was a shift toward complicated juxtra-renal aneurysms. In the past
Fellowship
several years, more aggressive endoluminal approaches and the introduction of fenestrated
Residency
grafts have appeared to dilute the open aneurysm operating experience. Coupled with work
Training
hours restrictions and shorter training paradigms, opportunities for training residents in open repair of abdominal aneurysms are decreasing. We envision that future treatment of complicated aortic aneurysms will likely entail advanced fellowship training in open repair and referral of complicated abdominal aneurysms to tertiary care centers. © 2013 Elsevier Inc. All rights reserved.
The ability to perform open aortic surgery by vascular surgery trainees has become a topic of concern as endovascular abdominal aneurysm repair (EVAR) has become the dominant method of repair over the last decade. Increased work hour regulations, changes in training paradigms including integrated programs, and a burgeoning of endovascular technology to treat juxtarenal aneurysms through fenestrated means collectively challenge vascular surgery educators to ensure trainee competency in open aneurysm repair.
Early EVAR experience and a changing paradigm in open surgical management of AAA Abdominal aortic aneurysms (AAA) have been treated through open means for over half a century. A proved and effective means for providing repair, two decades ago the primary area of controversy was whether this effective operation was best conducted through the transabdominal
or retroperitoneal route.1 Since Juan Parodi's introduction of the endovascular stent-graft for the treatment of infrarenal AAA in 1991,2 there has been a revolution in changing the treatment paradigm to an endoluminal approach through experimentation and subsequent mass-scale introduction of the first-generation endoluminal stent-grafts. Several institutions began early recognition of this change and catalogued their experience. In 2000, Washington University in St. Louis documented a decrease in open AAA volume from 61 cases in 1998–1999 to a predicted 36 in 1999–2000. During this time however, open suprarenal cases increased from 8 to 24 cases.3 Globally, several contemporary authors noted that the difficulty of open repair increased as uncomplicated infrarenal aneurysms were being treated through an endovascular approach.4-6 At about the same time at Baylor College of Medicine in Houston, the average pre-EVAR experience of vascular fellows was 40 open repairs versus 19 postEVAR introduction. The decrease of AAA experience for general surgery chief residents was approximately the same.5
Statement of Conflict of Interest: see page 17. ⁎ Address reprint requests to Gregorio A. Sicard, MD, 660 South Euclid, Campus Box 8109, St. Louis, MO 63110. E-mail address: [email protected] (G.A. Sicard). 0033-0620/$ – see front matter © 2013 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.pcad.2013.04.003
14
P R O G RE SS IN CAR D I O V A S CU L A R D I SE A S E S 5 6 ( 2 01 3 ) 1 3–1 8
Abbreviations and Acronyms
Ochsner clinic also documented the deAAA = abdominal aortic crease of their general aneurysms surgery chief resident EVAR = endovascular abdominal experience treating aneurysm repair AAA from an average of 10 in 1997 to 4 in 2001 (p = 0.03). Further, they too noted a growing trend of not only declining AAA cases but increased complexity of open repairs. They concluded that “[the] expectation that general surgery residents gain the proficiency necessary to safely perform AAA repair without additional training may be unrealistic.”4 Likewise, Stanford looked at a 6 year experience treating AAA and thoracoabdominal aneurysms 3 years preand post-EVAR. Though their early experience showed no change in open AAA repair (approximately 50 per vascular surgery fellow), suprarenal aneurysm numbers increased from 10 to 19 (p < 0.05).6 In sum, theses early experiences with first generation endografts initiated a trend of increased referral of aneurysms to academic centers with significant increase in EVAR volume. As selective aneurysms were chosen for endograft repair, the overall complexity of open repair increased and number of open repairs have decreased. With an increase in
Fig 1 – Fenestrated abdominal endograft. The Cook Fenestrated Endograft is seen here in a recent patient treated at the Barnes Jewish Hospital. Both renal vessels were fenestrated with covered stent grafts. The superior mesenteric artery (SMA) was scalloped and the fixation barbs are shown at the level of the SMA and celiac trunk.
treatment options and decrease in open experience for all trainees, we too believe that the general surgery trainee is not sufficiently trained to provide comprehensive abdominal aneurysm treatment. Over the course of the subsequent decade, it has become evident that more aggressive use of EVAR and the introduction of fenestrated grafts have further diluted the open aortic experience.
2000–2010: growing use of endovascular aneurysm repair These early experiences clearly foreshadowed the dominant treatment modality for AAA as endograft repair. As vascular surgeon experience and comfort have risen over the past decade, so too has endoluminal repair predominated over the traditional open approach. Further, aggressive endovascular management including fenestrated devices (Fig 1), snorkel/chimney adjuncts, and use of thoracic endografts beyond the instruction for use for infrarenal repair has further decreased the number of possible open repair opportunities for vascular trainees. Here, we show our institutional change in the declining open aortic experience with the rise of EVAR as the dominant treatment modality for aortic aneurysm (Figs 2 and 3). Recently, the qualitative impact of training in the past decade was assessed at the University of Pennsylvania looking at vascular surgeons' enjoyment and comfort level with repair of AAA. A total of 382 surgeons responded, with those completing fellowship after 2000 citing higher procedure related comfort with EVAR over open AAA (p = 0.001) and surgeons completing training before 2000 citing a higher level of
Fig 2 – Elective infrarenal AAA repair at Washington University in St. Louis (15 year experience). Between 2001 and 2005, there was a substantial increase in endoluminal AAA being performed with maintenance of open numbers. From 2006–2010, although endoluminal volume was maintained, the open volume dropped considerably, primarily attributed to more aggressive use of EVAR given gained experience.
P R O G RE S S I N CA RDI O V A S CU L A R D I SE A S E S 5 6 ( 2 0 13 ) 1 3–1 8
15
implications have important ramifications for training as regionalization of procedures and surgeon outcome data will likely push open AAA treatment into somewhat of a niche field.
2010-current: new training programs
Fig 3 – Complicated aneurysm repair at Washington University in St. Louis (15 year experience). Volume of suprarenal/pararenal aneurysms from 2001–2010 dropped since EVAR has become the dominant treatment modality. Fenestrated repairs begun in 2008, and we anticipate that as centers gain proficiency with this modality complicated open aneurysm repairs will continue to drop.
procedure-related comfort with open repair (p = 0.001).7 This review showed that the mean number of endoluminal cases grew from 45 to 63 per trainee from 2000 to 2010, with a drop of open infrarenal AAA from 36 to 18. Further, these authors interestingly showed that only 50% of post-2000 graduates stated they were “extremely comfortable” with open abdominal aortic aneurysm repair compared to near 80% of pre-2000 graduates. Clearly, graduating surgeons do not feel as confident as previously trained counterparts with traditional open repair. Trends of open and endovascular management of AAA have further been examined on the Medicare population by Sachs et al.8 Interestingly, they found that the number of ruptured AAA decreased 40% overall from 1995–2008, and of the ruptured repairs being done, 31% were done EVAR. Overall Accreditation Council on Graduate Medical Education numbers from this report catalogue a decrease in open AAA repair by fellows from 44/year to 22 from 1999 to 2008. With a decrease in ruptured aneurysms and growing EVAR for the emergent approach as well, there has been legitimate concern regarding the competency of not only elective but also emergent open AAA repair by contemporary vascular trainees. So do the numbers matter? Surgical outcomes for open AAA repair has been scrutinized, and recent data show that the surgeon's overall volume of open vascular operations, or “composite surgeon volume,” may be a more important indicator of in-hospital mortality as an endpoint for AAA repair outcomes. From a nationwide patient sample, composite surgeon volume remained a significant predictor of lower in-hospital mortality for open AAA repair (odds ratio, 0.994; 95% CI, p < .0001), whereas increasing volume of AAA repairs per surgeon did not predict in-hospital deaths.9 Further evidence suggests that individual surgeon volume may be more important than institutional volume.10 These
The traditional paradigm for vascular surgeons has been a five-year clinical training program in general surgery accompanied by a two-year vascular fellowship. This involved a significant amount of open and laparoscopic training that would be required of any surgeon performing complicated intraabdominal open surgery. “Fast-tracking,” or 4 + 2 programs, enable the vascular resident to complete the requisite training in both general and vascular surgery and become certified in both specialties, completing training in one year less. More recently, vascular residency programs enable certification in vascular surgery only and allow the training
Fig 4 – Transabdominal approach to infrarenal AAA repair. Inset shows a standard midline celiotomy incision. The transverse colon is elevated and small bowel mobilized to the right. The ligament of Treitz is mobilized and the posterior peritoneum is entered to expose the left renal vein superior and the abdominal aneurysm.
16
P R O G RE SS IN CAR D I O V A S CU L A R D I SE A S E S 5 6 ( 2 01 3 ) 1 3–1 8
Fig 5 – Retroperitoneal approach to AAA repair. After being placed in the R lateral decubitus position for retroperitoneal exposure, the abdominal wall is cut from lateral to the umbilicus to the twelfth rib, mobilizing the peritoneum medially and superiorly. Here, the ureter is identified and retracted laterally with a vessel loop. The aorta is shown along with the left renal vein and the gonadal vein has been ligated. This provides excellent exposure of the aorta and is particularly ideal for juxtarenal aneurysm repair of the aorta.
to be completed in only 5 years. The accelerated vascular residency has clearly become the training paradigm embraced throughout the vascular community, currently with more than 40 training programs in the United States after the first 5 years of being established. An additionally complicated facet is that endovascular surgery continues to be dynamic, with custom fenestrated grafts and new, off-the-shelf juxtrarenal components that are now becoming available. There is excitement for these new devices and more clinical experience is still needed, but it is unlikely that there will be any immediate halt in the push to “go-endo”, as the same training institutions will be on the forefront of endoluminal repair. The dilemma for training in open aortic surgery has become even more complicated as one takes a traditional training paradigm, with more years dedicated toward open operating, now truncated into 5 years, with an 80-hour workweek that will likely become even more restrictive in the future.11,12 Furthermore, it is likely that endoluminal vascular surgery will only become more dominant as time goes on. Traditionally, open aortic surgery has been completed by a general surgery chief resident or vascular surgery fellow after years of training in open surgery. Considering the external forces of fewer hours in the hospital, fewer open operations, and decreased exposure to other surgical specialties that operate in the abdomen, it is unlikely that the future vascular residency trainee will have the same level of open aortic surgery competency as prior trainees.
The future There are several solutions to prevent aortic surgery from becoming a lost art. It is important for future training to maintain the best patient outcomes by utilizing the most experienced hands. We believe, with the aforementioned barriers to conducting excellent open aortic surgery, that current training paradigms may be unable to adequately prepare the next generation of vascular surgeons for complicated open AAA repair. To this end, we recommend several solutions, including aortic fellowships for those interested in complicated aortic repair, familiarity and training in the retroperitoneal approach to aortic aneurysms, and regionalization of complicated open aortic repair to future aortic centers of excellence. Graduating vascular residents (integrated program) may seek advanced aortic technique training as advanced fellowships are becoming available for both fenestrated aortic techniques as well as complicated open aortic repair. With the constriction of work hours, this may be a tenable solution to maintain competency and to obtain the experience required to perform excellent aortic surgery. Advanced aortic fellowships are currently available in a few institutions, and we anticipate that these programs will continue to increase in number, as there will always be a necessity to have surgeons well trained in open aortic technique. Access to international sites where foreign exchange may permit advanced trainees
P R O G RE S S I N CA RDI O V A S CU L A R D I SE A S E S 5 6 ( 2 0 13 ) 1 3–1 8
17
Fig 6 – High retroperitoneal approach to AAA repair. The inset shows a higher incision with the patient in a more steep right lateral decubitus position. This exposure provides excellent access to the suprarenal abdominal aorta.
to achieve mutual goals in both fenestrated endovascular repair, and open aortic repair could be another option. Most surgeons who perform open abdominal aortic repair are comfortable and perhaps most experienced with the transabdominal approach to open repair (Fig 4). The retroperitoneal approach, however, provides excellent exposure for the repair of juxtrarenal (Fig 5) or suprarenal abdominal aortic aneurysms (Fig 6).13 As the number of complicated suprarenal cases has grown, familiarity with this approach will be an important tool in the armamentarium of the future open aortic surgeon. Open aortic simulation will undoubtedly play a role in minimizing the learning curve for vascular trainees, and the profession will have to start establishing quantitative metrics of performance that will translate into improved surgical training.14 Lastly, regionalization to aortic centers of excellence may became an eventual reality, as advanced training and fewer open operations make complicated open approaches less tenable in smaller hospital settings. Recent reporting has shown superior outcomes from regionalization of rural patients to high-volume treatment centers, suggesting that quality of aortic care may matter even within the urban setting.15 Training aside, the ageing group of general surgeons still practicing aortic repair will also continue to retire. Also, although cardiac surgery and vascular surgery are now mutually exclusive fields, there may be a role for a contemporary “cardiovascular surgeon” whose role in thoracoabdominal and advanced endoluminal aortic surgery may require expertise in both areas. This may be seen as an elite group whose role would be primarily relegated to comprehensive advanced aortic surgery at a tertiary care center.
Collectively, there will always be a role for open aortic surgery and the necessity to provide it in training environments to ensure excellent treatment of vascular patients for years to come. Complicated aortic repair is built upon years of open surgical training and experience. This training paradigm is now threatened with advanced endoluminal technology and fewer opportunities for open aortic operating. The development of aortic sub-specialization and referral to centers of vascular excellence may usher in a new chapter in the referral patterns for future treatment of complicated aortic pathology.
Statement of Conflict of Interest All authors declare that there are no conflicts of interest.
Acknowledgments This manuscript was not funded by any grant support. REFERENCES
1. Sicard GA, Reilly JM, Rubin BG, et al. Transabdominal versus retroperitoneal incision for abdominal aortic surgery: report of a prospective randomized trial. J Vasc Surg. 1995;21:174-181. [discussion 81–3]. 2. Parodi JC, Palmaz JC, Barone HD. Transfemoral intraluminal graft implantation for abdominal aortic aneurysms. Ann Vasc Surg. 1991;5:491-499.
18
P R O G RE SS IN CAR D I O V A S CU L A R D I SE A S E S 5 6 ( 2 01 3 ) 1 3–1 8
3. Choi ET, Wyble CW, Rubin BG, et al. Evolution of vascular fellowship training in the new era of endovascular techniques. J Vasc Surg. 2001;33:S106-S110. 4. Sternbergh III WC, York JW, Conners III MS, Money SR. Trends in aortic aneurysm surgical training for general and vascular surgery residents in the era of endovascular abdominal aortic aneurysm repair. J Vasc Surg. 2002;36:685-689. 5. Lin PH, Bush RL, Milas M, et al. Impact of an endovascular program on the operative experience of abdominal aortic aneurysm in vascular fellowship and general surgery residency. Am J Surg. 2003;186:189-193. 6. Arko FR, Lee WA, Hill BB, et al. Impact of endovascular repair on open aortic aneurysm surgical training. J Vasc Surg. 2001;34:885-891. 7. Ullery BW, Nathan DP, Jackson BM, Wang GJ, Fairman RM, Woo EY. Qualitative impact of the endovascular era on vascular surgeons' comfort level and enjoyment with open and endovascular AAA repairs. Vasc Endovascular Surg. 2012;46:150-156. 8. Sachs T, Schermerhorn M, Pomposelli F, Cotterill P, O'Malley J, Landon B. Resident and fellow experiences after the introduction of endovascular aneurysm repair for abdominal aortic aneurysm. J Vasc Surg. 2011;54:881-888. 9. Modrall JG, Rosero EB, Chung J, et al. Defining the type of surgeon volume that influences the outcomes for
10.
11.
12.
13.
14.
15.
open abdominal aortic aneurysm repair. J Vasc Surg. 2011;54: 1599-1604. McPhee JT, Robinson III WP, Eslami MH, Arous EJ, Messina LM, Schanzer A. Surgeon case volume, not institution case volume, is the primary determinant of in-hospital mortality after elective open abdominal aortic aneurysm repair. J Vasc Surg. 2011;53:591-599.e2. Lee DY, Myers EA, Rehmani SS, et al. Surgical residents' perception of the 16-hour work day restriction: concern for negative impact on resident education and patient care. J Am Coll Surg. 2012;215:868-877. Watson DR, Flesher TD, Ruiz O, Chung JS. Impact of the 80-hour workweek on surgical case exposure within a general surgery residency program. J Surg Educ. 2010;67: 283-289. Sicard GA, Allen BT, Munn JS, Anderson CB. Retroperitoneal versus transperitoneal approach for repair of abdominal aortic aneurysms. Surg Clin North Am. 1989;69:795-806. Fonseca AL, Evans LV, Gusberg RJ. Open surgical simulation in residency training: a review of its status and a case for its incorporation. J Surg Educ. 2013;70:129-137. Mell MW, Bartels C, Kind A, Leverson G, Smith M. Superior outcomes for rural patients after abdominal aortic aneurysm repair supports a systematic regional approach to abdominal aortic aneurysm care. J Vasc Surg. 2012;56:608-613.
Available online at www.sciencedirect.com
ScienceDirect www.onlinepcd.com
Surgical Management of Abdominal Aortic Aneurysms: A Lost Art? Abdulhameed Aziz, Gregorio A. Sicard⁎ Section of Vascular Surgery, Department of Surgery, Washington University in St. Louis School of Medicine, St. Louis, MO A R T I C LE I N F O
AB ST R A C T
Keywords:
Endovascular repair of abdominal aneurysms has become the dominant treatment
Aorta
modality for infrarenal aneurysms. Initial reports showed a constant number of open
Aneurysms
repairs although there was a shift toward complicated juxtra-renal aneurysms. In the past
Fellowship
several years, more aggressive endoluminal approaches and the introduction of fenestrated
Residency
grafts have appeared to dilute the open aneurysm operating experience. Coupled with work
Training
hours restrictions and shorter training paradigms, opportunities for training residents in open repair of abdominal aneurysms are decreasing. We envision that future treatment of complicated aortic aneurysms will likely entail advanced fellowship training in open repair and referral of complicated abdominal aneurysms to tertiary care centers. © 2013 Elsevier Inc. All rights reserved.
The ability to perform open aortic surgery by vascular surgery trainees has become a topic of concern as endovascular abdominal aneurysm repair (EVAR) has become the dominant method of repair over the last decade. Increased work hour regulations, changes in training paradigms including integrated programs, and a burgeoning of endovascular technology to treat juxtarenal aneurysms through fenestrated means collectively challenge vascular surgery educators to ensure trainee competency in open aneurysm repair.
Early EVAR experience and a changing paradigm in open surgical management of AAA Abdominal aortic aneurysms (AAA) have been treated through open means for over half a century. A proved and effective means for providing repair, two decades ago the primary area of controversy was whether this effective operation was best conducted through the transabdominal
or retroperitoneal route.1 Since Juan Parodi's introduction of the endovascular stent-graft for the treatment of infrarenal AAA in 1991,2 there has been a revolution in changing the treatment paradigm to an endoluminal approach through experimentation and subsequent mass-scale introduction of the first-generation endoluminal stent-grafts. Several institutions began early recognition of this change and catalogued their experience. In 2000, Washington University in St. Louis documented a decrease in open AAA volume from 61 cases in 1998–1999 to a predicted 36 in 1999–2000. During this time however, open suprarenal cases increased from 8 to 24 cases.3 Globally, several contemporary authors noted that the difficulty of open repair increased as uncomplicated infrarenal aneurysms were being treated through an endovascular approach.4-6 At about the same time at Baylor College of Medicine in Houston, the average pre-EVAR experience of vascular fellows was 40 open repairs versus 19 postEVAR introduction. The decrease of AAA experience for general surgery chief residents was approximately the same.5
Statement of Conflict of Interest: see page 17. ⁎ Address reprint requests to Gregorio A. Sicard, MD, 660 South Euclid, Campus Box 8109, St. Louis, MO 63110. E-mail address: [email protected] (G.A. Sicard). 0033-0620/$ – see front matter © 2013 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.pcad.2013.04.003
14
P R O G RE SS IN CAR D I O V A S CU L A R D I SE A S E S 5 6 ( 2 01 3 ) 1 3–1 8
Abbreviations and Acronyms
Ochsner clinic also documented the deAAA = abdominal aortic crease of their general aneurysms surgery chief resident EVAR = endovascular abdominal experience treating aneurysm repair AAA from an average of 10 in 1997 to 4 in 2001 (p = 0.03). Further, they too noted a growing trend of not only declining AAA cases but increased complexity of open repairs. They concluded that “[the] expectation that general surgery residents gain the proficiency necessary to safely perform AAA repair without additional training may be unrealistic.”4 Likewise, Stanford looked at a 6 year experience treating AAA and thoracoabdominal aneurysms 3 years preand post-EVAR. Though their early experience showed no change in open AAA repair (approximately 50 per vascular surgery fellow), suprarenal aneurysm numbers increased from 10 to 19 (p < 0.05).6 In sum, theses early experiences with first generation endografts initiated a trend of increased referral of aneurysms to academic centers with significant increase in EVAR volume. As selective aneurysms were chosen for endograft repair, the overall complexity of open repair increased and number of open repairs have decreased. With an increase in
Fig 1 – Fenestrated abdominal endograft. The Cook Fenestrated Endograft is seen here in a recent patient treated at the Barnes Jewish Hospital. Both renal vessels were fenestrated with covered stent grafts. The superior mesenteric artery (SMA) was scalloped and the fixation barbs are shown at the level of the SMA and celiac trunk.
treatment options and decrease in open experience for all trainees, we too believe that the general surgery trainee is not sufficiently trained to provide comprehensive abdominal aneurysm treatment. Over the course of the subsequent decade, it has become evident that more aggressive use of EVAR and the introduction of fenestrated grafts have further diluted the open aortic experience.
2000–2010: growing use of endovascular aneurysm repair These early experiences clearly foreshadowed the dominant treatment modality for AAA as endograft repair. As vascular surgeon experience and comfort have risen over the past decade, so too has endoluminal repair predominated over the traditional open approach. Further, aggressive endovascular management including fenestrated devices (Fig 1), snorkel/chimney adjuncts, and use of thoracic endografts beyond the instruction for use for infrarenal repair has further decreased the number of possible open repair opportunities for vascular trainees. Here, we show our institutional change in the declining open aortic experience with the rise of EVAR as the dominant treatment modality for aortic aneurysm (Figs 2 and 3). Recently, the qualitative impact of training in the past decade was assessed at the University of Pennsylvania looking at vascular surgeons' enjoyment and comfort level with repair of AAA. A total of 382 surgeons responded, with those completing fellowship after 2000 citing higher procedure related comfort with EVAR over open AAA (p = 0.001) and surgeons completing training before 2000 citing a higher level of
Fig 2 – Elective infrarenal AAA repair at Washington University in St. Louis (15 year experience). Between 2001 and 2005, there was a substantial increase in endoluminal AAA being performed with maintenance of open numbers. From 2006–2010, although endoluminal volume was maintained, the open volume dropped considerably, primarily attributed to more aggressive use of EVAR given gained experience.
P R O G RE S S I N CA RDI O V A S CU L A R D I SE A S E S 5 6 ( 2 0 13 ) 1 3–1 8
15
implications have important ramifications for training as regionalization of procedures and surgeon outcome data will likely push open AAA treatment into somewhat of a niche field.
2010-current: new training programs
Fig 3 – Complicated aneurysm repair at Washington University in St. Louis (15 year experience). Volume of suprarenal/pararenal aneurysms from 2001–2010 dropped since EVAR has become the dominant treatment modality. Fenestrated repairs begun in 2008, and we anticipate that as centers gain proficiency with this modality complicated open aneurysm repairs will continue to drop.
procedure-related comfort with open repair (p = 0.001).7 This review showed that the mean number of endoluminal cases grew from 45 to 63 per trainee from 2000 to 2010, with a drop of open infrarenal AAA from 36 to 18. Further, these authors interestingly showed that only 50% of post-2000 graduates stated they were “extremely comfortable” with open abdominal aortic aneurysm repair compared to near 80% of pre-2000 graduates. Clearly, graduating surgeons do not feel as confident as previously trained counterparts with traditional open repair. Trends of open and endovascular management of AAA have further been examined on the Medicare population by Sachs et al.8 Interestingly, they found that the number of ruptured AAA decreased 40% overall from 1995–2008, and of the ruptured repairs being done, 31% were done EVAR. Overall Accreditation Council on Graduate Medical Education numbers from this report catalogue a decrease in open AAA repair by fellows from 44/year to 22 from 1999 to 2008. With a decrease in ruptured aneurysms and growing EVAR for the emergent approach as well, there has been legitimate concern regarding the competency of not only elective but also emergent open AAA repair by contemporary vascular trainees. So do the numbers matter? Surgical outcomes for open AAA repair has been scrutinized, and recent data show that the surgeon's overall volume of open vascular operations, or “composite surgeon volume,” may be a more important indicator of in-hospital mortality as an endpoint for AAA repair outcomes. From a nationwide patient sample, composite surgeon volume remained a significant predictor of lower in-hospital mortality for open AAA repair (odds ratio, 0.994; 95% CI, p < .0001), whereas increasing volume of AAA repairs per surgeon did not predict in-hospital deaths.9 Further evidence suggests that individual surgeon volume may be more important than institutional volume.10 These
The traditional paradigm for vascular surgeons has been a five-year clinical training program in general surgery accompanied by a two-year vascular fellowship. This involved a significant amount of open and laparoscopic training that would be required of any surgeon performing complicated intraabdominal open surgery. “Fast-tracking,” or 4 + 2 programs, enable the vascular resident to complete the requisite training in both general and vascular surgery and become certified in both specialties, completing training in one year less. More recently, vascular residency programs enable certification in vascular surgery only and allow the training
Fig 4 – Transabdominal approach to infrarenal AAA repair. Inset shows a standard midline celiotomy incision. The transverse colon is elevated and small bowel mobilized to the right. The ligament of Treitz is mobilized and the posterior peritoneum is entered to expose the left renal vein superior and the abdominal aneurysm.
16
P R O G RE SS IN CAR D I O V A S CU L A R D I SE A S E S 5 6 ( 2 01 3 ) 1 3–1 8
Fig 5 – Retroperitoneal approach to AAA repair. After being placed in the R lateral decubitus position for retroperitoneal exposure, the abdominal wall is cut from lateral to the umbilicus to the twelfth rib, mobilizing the peritoneum medially and superiorly. Here, the ureter is identified and retracted laterally with a vessel loop. The aorta is shown along with the left renal vein and the gonadal vein has been ligated. This provides excellent exposure of the aorta and is particularly ideal for juxtarenal aneurysm repair of the aorta.
to be completed in only 5 years. The accelerated vascular residency has clearly become the training paradigm embraced throughout the vascular community, currently with more than 40 training programs in the United States after the first 5 years of being established. An additionally complicated facet is that endovascular surgery continues to be dynamic, with custom fenestrated grafts and new, off-the-shelf juxtrarenal components that are now becoming available. There is excitement for these new devices and more clinical experience is still needed, but it is unlikely that there will be any immediate halt in the push to “go-endo”, as the same training institutions will be on the forefront of endoluminal repair. The dilemma for training in open aortic surgery has become even more complicated as one takes a traditional training paradigm, with more years dedicated toward open operating, now truncated into 5 years, with an 80-hour workweek that will likely become even more restrictive in the future.11,12 Furthermore, it is likely that endoluminal vascular surgery will only become more dominant as time goes on. Traditionally, open aortic surgery has been completed by a general surgery chief resident or vascular surgery fellow after years of training in open surgery. Considering the external forces of fewer hours in the hospital, fewer open operations, and decreased exposure to other surgical specialties that operate in the abdomen, it is unlikely that the future vascular residency trainee will have the same level of open aortic surgery competency as prior trainees.
The future There are several solutions to prevent aortic surgery from becoming a lost art. It is important for future training to maintain the best patient outcomes by utilizing the most experienced hands. We believe, with the aforementioned barriers to conducting excellent open aortic surgery, that current training paradigms may be unable to adequately prepare the next generation of vascular surgeons for complicated open AAA repair. To this end, we recommend several solutions, including aortic fellowships for those interested in complicated aortic repair, familiarity and training in the retroperitoneal approach to aortic aneurysms, and regionalization of complicated open aortic repair to future aortic centers of excellence. Graduating vascular residents (integrated program) may seek advanced aortic technique training as advanced fellowships are becoming available for both fenestrated aortic techniques as well as complicated open aortic repair. With the constriction of work hours, this may be a tenable solution to maintain competency and to obtain the experience required to perform excellent aortic surgery. Advanced aortic fellowships are currently available in a few institutions, and we anticipate that these programs will continue to increase in number, as there will always be a necessity to have surgeons well trained in open aortic technique. Access to international sites where foreign exchange may permit advanced trainees
P R O G RE S S I N CA RDI O V A S CU L A R D I SE A S E S 5 6 ( 2 0 13 ) 1 3–1 8
17
Fig 6 – High retroperitoneal approach to AAA repair. The inset shows a higher incision with the patient in a more steep right lateral decubitus position. This exposure provides excellent access to the suprarenal abdominal aorta.
to achieve mutual goals in both fenestrated endovascular repair, and open aortic repair could be another option. Most surgeons who perform open abdominal aortic repair are comfortable and perhaps most experienced with the transabdominal approach to open repair (Fig 4). The retroperitoneal approach, however, provides excellent exposure for the repair of juxtrarenal (Fig 5) or suprarenal abdominal aortic aneurysms (Fig 6).13 As the number of complicated suprarenal cases has grown, familiarity with this approach will be an important tool in the armamentarium of the future open aortic surgeon. Open aortic simulation will undoubtedly play a role in minimizing the learning curve for vascular trainees, and the profession will have to start establishing quantitative metrics of performance that will translate into improved surgical training.14 Lastly, regionalization to aortic centers of excellence may became an eventual reality, as advanced training and fewer open operations make complicated open approaches less tenable in smaller hospital settings. Recent reporting has shown superior outcomes from regionalization of rural patients to high-volume treatment centers, suggesting that quality of aortic care may matter even within the urban setting.15 Training aside, the ageing group of general surgeons still practicing aortic repair will also continue to retire. Also, although cardiac surgery and vascular surgery are now mutually exclusive fields, there may be a role for a contemporary “cardiovascular surgeon” whose role in thoracoabdominal and advanced endoluminal aortic surgery may require expertise in both areas. This may be seen as an elite group whose role would be primarily relegated to comprehensive advanced aortic surgery at a tertiary care center.
Collectively, there will always be a role for open aortic surgery and the necessity to provide it in training environments to ensure excellent treatment of vascular patients for years to come. Complicated aortic repair is built upon years of open surgical training and experience. This training paradigm is now threatened with advanced endoluminal technology and fewer opportunities for open aortic operating. The development of aortic sub-specialization and referral to centers of vascular excellence may usher in a new chapter in the referral patterns for future treatment of complicated aortic pathology.
Statement of Conflict of Interest All authors declare that there are no conflicts of interest.
Acknowledgments This manuscript was not funded by any grant support. REFERENCES
1. Sicard GA, Reilly JM, Rubin BG, et al. Transabdominal versus retroperitoneal incision for abdominal aortic surgery: report of a prospective randomized trial. J Vasc Surg. 1995;21:174-181. [discussion 81–3]. 2. Parodi JC, Palmaz JC, Barone HD. Transfemoral intraluminal graft implantation for abdominal aortic aneurysms. Ann Vasc Surg. 1991;5:491-499.
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