Donor Vessels Research Articles

Free Flap Reconstruction of the Knee

Open wounds around the knee joint can often be managed with local flaps; however, free tissue transfer may be required when local tissue options are unavailable or inadequate. Free tissue transfer around the knee can be challenging due to unique anatomic features of the joint. The outcomes of such procedures remain largely unreported. We retrospectively analyzed 33 patients who underwent 34 free tissue transfer reconstructions to the knee from 1993 to 2010. Twenty-four flaps were composed of soft tissue only and 10 flaps included a bony component. Patient demographics, details of the defect, operative characteristics, and clinical outcomes were reviewed. Outcomes included rates of flap failure, flap reexploration, and limb salvage. Thirty-three (97%) of 34 flaps survived. One flap failed secondary to arterial thrombosis. In total, 6/34 flaps (18%) required reexploration (2 arterial thromboses and 4 venous thromboses). A wide variety of donor and recipient vessels were used. Vessel selection did not affect vascular reexploration. Overall, 88% of lower extremities were salvaged. Four of 10 (40%) patients receiving bone free flap reconstruction experienced delayed union and 2 (20%) of these required amputation for eventual nonunion. Free flap reconstruction of the knee has a high flap survival and limb preservation rate in threatened extremities. Flap survival rates in the knee are similar to reported rates elsewhere in the lower extremity. Despite flap survival, infected nonunions that occur after bone free flap reconstruction result in a high limb amputation rate.

Fluid dynamic characterization of a novel branching anastomosis design

Geometric characteristics of a vascular anastomosis can have important biomechanical impacts, particularly in the hemodynamic context of wall shear stress (WSS). In this study, we propose a new branching anastomosis design, the Hybrid anastomosis, to connect a donor vessel to two recipient vessels. The central obstruction characteristic of the traditional Figure 8 anastomosis is mitigated by creating a recessed lumen at the bifurcation. Chicken vessels were used to create and test three Figure 8 and three Hybrid anastomoses ex vivo. Computational fluid dynamics (CFD) simulations of idealized anastomosis designs were then used to verify the experiments and further studied the WSS and WSS gradient (WSSG) profiles of the designs. Experimental results showed increased flow through the Hybrid anastomosis (0.40 ml/s vs. 0.23 ml/s). The mean suture time averaged 20 and 28 min for the Figure 8 and Hybrid anastomoses, respectively. CFD simulations agreed with the experiments; the simulations showed lower flow resistance in the Hybrid anastomosis (1.89 kPa-s/ml vs. 6.77 kPa-s/ml). Most importantly, a set of more physiologically realistic simulations showed that the Hybrid anastomosis reduced WSS and WSSG by over 60% as compared to the Figure 8. Results demonstrated that the proposed Hybrid anastomosis can be created on a comparable surgical time scale (and from the same initial vasculature) as compared to the Figure 8 anastomosis, while decreasing flow resistance and reducing WSS and WSSG considerably. These findings support that the new Hybrid anastomosis may represent a favorable surgical alternative to the Figure 8 design.

Measurements of hemodynamics of internal maxillary artery to intracranial arterial bypasses via intraoperative duplex ultrasonography

Objective To explore the hemodynamics of internal maxillary artery (IMA)-intracranial arterial bypasses via intraoperative duplex ultrasonography.Methods The hemodynamic parameters (flow volume,inside diameter,mean flow velocity,pulse index and resistance index) were compared between normal IMA (n =15),IMA-radial artery (RA)-MCA (n =35) bypass,IMA-RA-PCA (n =7) bypass and superficial temporal artery(STA)-MCA bypass (n =10) by measuring the flow via intraoperative duplex ultrasonography.Results There was no significant difference in inside diameter between IMA and RA (2.49 ±0.31)mm vs (2.47 ±0.26)mm,P =0.812).The average flow was (81.8 ±19.0)ml/min for normal IMA,(69.6± 163)ml/min for IMA -RA-MCA bypass and (48.0 ± 8.8) ml/min for IMA-RA-PCA bypass,which were significantly higher than that of STA-MCA bypass (31.0 ± 8.4) ml/min (P =0.000,0.000 and 0.001).The donor vessel (IMA vs STA) and recipient vessel (MCA vs PCA) could impact the flow through bypasses.Condusions IMA could deliver a short segment high blood flow as a donor vessel for extracranial-intracranial bypass.The suitable inside diameter of IMA and RA could make an end-to-end anastomosis be performed directly.IMA-RA-MCA/PCA bypasses could supply middle to high flow capacity for brain.The donor vessel and recipient vessel might impact the final blood flow volume through extracranial-intracranial bypass. Key words: Internal maxillary artery-intracranial arterial bypass ; Superficial temporal artery to middle cerebral artery bypass; Intraoperative duplex ultrasonography; Hemodynamics; Measurement

Murine cervical heart transplantation model using a modified cuff technique.

Mouse models are of special interest in research since a wide variety of monoclonal antibodies and commercially defined inbred and knockout strains are available to perform mechanistic in vivo studies. While heart transplantation models using a suture technique were first successfully developed in rats, the translation into an equally widespread used murine equivalent was never achieved due the technical complexity of the microsurgical procedure. In contrast, non-suture cuff techniques, also developed initially in rats, were successfully adapted for use in mice(1-3). This technique for revascularization involves two major steps I) everting the recipient vessel over a polyethylene cuff; II) pulling the donor vessel over the formerly everted recipient vessel and holding it in place with a circumferential tie. This ensures a continuity of the endothelial layer, short operating time and very high patency rates(4). Using this technique for vascular anastomosis we performed more than 1,000 cervical heart transplants with an overall success rate of 95%. For arterial inflow the common carotid artery and the proximal aortic arch were anastomosed resulting in a retrograde perfusion of the transplanted heart. For venous drainage the pulmonary artery of the graft was anastomosed with the external jugular vein of the recipient(5). Herein, we provide additional details of this technique to supplement the video.

Murine Cervical Heart Transplantation Model Using a Modified Cuff Technique

Mouse models are of special interest in research since a wide variety of monoclonal antibodies and commercially defined inbred and knockout strains are available to perform mechanistic in vivo studies. While heart transplantation models using a suture technique were first successfully developed in rats, the translation into an equally widespread used murine equivalent was never achieved due the technical complexity of the microsurgical procedure. In contrast, non-suture cuff techniques, also developed initially in rats, were successfully adapted for use in mice1-3. This technique for revascularization involves two major steps I) everting the recipient vessel over a polyethylene cuff; II) pulling the donor vessel over the formerly everted recipient vessel and holding it in place with a circumferential tie. This ensures a continuity of the endothelial layer, short operating time and very high patency rates4. Using this technique for vascular anastomosis we performed more than 1,000 cervical heart transplants with an overall success rate of 95%. For arterial inflow the common carotid artery and the proximal aortic arch were anastomosed resulting in a retrograde perfusion of the transplanted heart. For venous drainage the pulmonary artery of the graft was anastomosed with the external jugular vein of the recipient5. Herein, we provide additional details of this technique to supplement the video.

Smooth muscle cells from the anastomosed artery are the major precursors for neointima formation in both artery and vein grafts.

Accumulation of smooth muscle cells (SMC) results in neointima formation in injured vessels. Two graft models consisting of vein and artery grafts were created by anastomosing common carotid arteries to donor vessels. To identify the origin of the neointima cells from anastomosed arteries, we use Wnt1-Cre/reporter mice to label and track SMCs in the common carotid artery. The contribution of SMCs in the neighboring arteries to neointima formation was studied. On evaluating the artery grafts after 1 month, >90 % of the labeled neointima cells were found to have originated from the anastomosing host arteries. Most of the neointima cells were also smooth muscle α-actin positive (SMA-α(+)) and expressed the smooth muscle myosin heavy chain (SMMHC), the SMC terminal differentiation marker. In vein grafts, about 60 % SMA-α-positive cells were from anastomosing arteries. Bone marrow cells did not contribute to neointima SMCs in vein grafts, but did co-stain with markers of inflammatory cells. Wnt1 expression was not detected in the neointima cells in the vein or artery grafts, or the injured femoral arteries. Neointima SMCs showed the synthetic phenotype and were positively labeled with BrdU in vitro and in vivo. Treatment with the IGF-1 receptor inhibitor suppressed SMC proliferation and neointima formation in vein grafts. Our results indicate that SMCs from the neighboring artery are predominantly present in the neointima formed in both vein and artery grafts and that Wnt1-Cre mice can be used to explore the role of SMCs originating from neighboring vessels in vascular remodeling.

Use of superior thyroid artery as a donor vessel in extracranial-intracranial revascularization procedures: a novel technique.

Objective To describe the use of the superior thyroid artery as a donor vessel in extracranial-intracranial (EC-IC) revascularization when a "low-flow" bypass is required and the superficial temporal artery is not available. Design Case report. Setting University hospital. Participants Four cases. Main Outcome Measures Postoperative course after EC-IC bypass surgery. Results In case 1, the parent vessel was occluded postoperatively. The radial bypass was sufficient to replace the internal carotid artery (ICA) flow, and a prophylactic was turned into a definitive bypass. In case 2, the superior thyroid artery was used because the radial artery was not long enough to reach the external carotid artery. The recipient vessel was modified from the middle cerebral artery to the ophthalmic segment of the ICA. In case 3, the graft was occluded after surgery because of carotid artery reconstruction. In case 4, after surgery/radiotherapy for meningioma, the patient developed wound dehiscence and was reoperated for bypass occlusion. The graft was weak and bled intraoperatively, without infarction. The three first patients are intact, and the fourth remains disabled (Glasgow Outcome Scale: 3; Rankin Scale: 5). Conclusion The superior thyroid artery was adequate for proximal anastomosis in EC-IC procedures in the situations described.

Mesenchymal Stem Cell Therapy to Promote Sensory and Motor Nerve Function in a Limb Transplant Model.

Introduction: Hand and leg transplantation (Tx) in military/civilian populations is increasingly needed to improve the quality of life of individuals. Optimizing nerve regeneration and preventing immune rejection are vital to successful outcomes in limb Tx. As a first step, our objective was to investigate whether bone marrow derived mesenchymal stem cells (MSCs) can improve nerve regeneration and function. Methods: We performed orthotopic syngeneic hind-limb transplants in Lewis (RT1. Al) rats. Osteosynthesis of femur was performed using intramedullary pin and bone cement. The donor and recipient vessels were anastomosed using the vascular cuff technique. The sciatic nerve ends were approximated using 10-O nylon sutures. Rats received syngeneic MSC (5x106; passage ≤8; n=8) or vehicle (n=7) locally (nerve, bone and vascular anastomoses sites) and intravenously. Following Tx ( ≥2 weeks) laser doppler and radiologic analysis were performed to assess limb vascularization and fusion of native and graft femoral ends. Sensory function of the transplanted limb was assessed by cutaneous pain reaction test and motor function by walking track analysis every 1-2 weeks until 26 weeks post-Tx. Results:Ex vivo expanded Rat MSCs were CD29+, CD31-, CD34-, CD44+, CD45low, CD90+, MHC Class I+, Class II- and were pluripotent: differentiated in to adipocytes, osteocytes and chondrocytes in ex vivo cultures. Limb Tx was highly successful (100% survival). Four weeks post-Tx sensory nerve function was <0.3 on a scale of Grade 0 to 3 (0=No function; 3=Normal function). By 8 weeks in vehicle group it was 2.2±0.7 (tibial), 1.2±0.5 (peroneal) and 1.7±0.9 (sural), and in MSC group it was 2.6±0.4 (tibial), 1.0±0.9 (peroneal) and 1.7±0.9 (sural). Overall sensory function was higher but not significant in MSC group compared to vehicle group at 4, 8, 16 and 24 weeks post-Tx. Walking track analysis (for motor nerve function) did not produce clear foot prints to calculate Sciatic Function Index (SFI), so a novel grading system for available foot prints was developed. Radiology and laser doppler analysis revealed normal bone fusion and vascularization, respectively. Gastrocnemius muscle was atrophied (P<0.05) and animals developed flexion-contractures in the transplanted limb. Conclusion: The limb transplantation procedure was highly successful, sensory function was recovered (>70%) and MSC therapy appears to promote transplanted limb nerve functional recovery.

Augmented Reality-Assisted Extracranial-to-Intracranial Bypass Surgery

Aim: Harvesting of a donor vessel and the choice of a recipient vessel are two essential steps during extracranial-to-intracranial (EC-IC) bypass surgery1-3. Manual pulse palpation, Doppler probes and angiographical “road-mapping” have been used to draw the trajectory of the extracranial donor vessels; and the identification of an appropriate intracranial vessel is based upon detailed analysis of the preoperative angiography and on intraoperative inspection of cortical vessels. Augmented reality is defined as the overlay of virtual images upon real-world structures, and this technology has been used in various surgical settings4,5. We investigate the usefulness of augmented reality-based microscope image-injection during these two phases of EC-IC bypass surgery.

72 Non-Target Vessel Haemodynamics Prior to Angioplasty of Chronic Total Coronary Occlusions, is There Really Substrate for an Important Change in Haemodynamic Lesion Severity?

IntroductionFractional flow reserve (FFR) guided angioplasty has been shown to have a beneficial effect on clinical outcome in patients with multi-vessel coronary disease. However, multi-vessel disease is frequently accompanied by...

Wow, that portal vein is small: Preventing portal vein thrombosis in liver transplantation for small children

Portal vein thrombosis after pediatric liver transplantation is a common and devastating complication. Occurring in up to 8% of pediatric liver transplant recipients who are less than 15 kg, it frequently leads to graft loss and the need for emergent retransplantation.1, 2 Children with biliary atresia are at particularly high risk and often develop an atretic portal vein; this makes the portal vein anastomosis particularly difficult. Adding further complexity is the frequent use of left lateral segment allografts, which frequently introduce portal vein size mismatching and orientation issues. Several options exist for managing the technical challenges related to portal vein anastomoses. Although the traditional approach has been end-to-end portal vein anastomoses, size differences often make this approach impossible. When this is the case, a proximal mesenteric vein anastomosis, branch vein patch, or donor venoplasty may be necessary to complete the anastomosis.3 When angulation issues result in low portal flow after transplantation, augmentation can be achieved through the ligation of the left renal vein or other mesocentral venous collaterals. Portocaval and porto-arterial anastomoses have also been proposed to increase flow. Although these approaches may effectively lower the risk of portal vein thrombosis after liver transplantation, they are less than optimal solutions for pediatric recipients with diminutive portal veins or preoperative portal vein thrombosis. A potential answer to this issue may be the use of a renoportal anastomosis. This approach has been described in adult liver transplantation with promising results.4 In pediatric patients, we believe that this technique provides a unique solution to issues relating to flow, size, and orientation mismatch. In general, there are no specific criteria for using a renoportal anastomosis; however, we find that size mismatch and portal flow issues are the most frequent indications. If the recipient portal vein measures 2 to 3 mm in size or is less than half the diameter of the donor portal vein, we often consider this technique. Additionally, if the portal vein flow is inadequate despite clamping of the left renal vein, we will also consider this approach. An appropriately sized venous conduit is prepared; this depends on the size relationship between the donor and recipient vessels. Suitable conduits include the external iliac vein, femoral vein, superior mesenteric vein, splenic vein, and saphenous vein (for living donors). The procurement of all these potential conduits is appropriate to facilitate as many technical options as possible during the transplant operation. The transplant hepatectomy proceeds as usual. As much length as possible of the recipient portal vein should be maintained. Before the completion of the hepatectomy and the clamping of the portal vein and inferior vena cava, the left renal vein of the recipient is exposed. On the back table, an end-to-end anastomosis is fashioned between the left portal vein of the donor and the vein conduit. The liver is brought to the field, and the hepatic vein anastomosis is completed. A clamp is placed on the recipient left renal vein toward the kidney, and the vein is ligated at the level of the inferior vena cava. The renoportal anastomosis is created between the conduit and the left renal vein. The clamps are removed, and the liver is reperfused. Once the bleeding is under control, a partial clamp is placed on the side of the vein conduit. An anastomosis is created between the end of the recipient portal vein and the side of the donor conduit (Fig. 1). The portal vein clamp is removed, and the arterial anastomosis is completed. In conclusion, using a renoportal anastomosis for hepatic portal inflow overcomes 2 issues that commonly challenge pediatric liver transplantation in small children. First, the renal vein, the donor left portal vein, and the conduit are well matched in size. Second, there frequently is little flow through the mesenteric venous system of these small children. Using the left renal vein as inflow provides a reliable amount of flow to the allograft. Although the sewing of the donor portal vein to the iliac vein conduit may not be necessary, it dilates with time and frequently becomes the dominant inflow to the liver. Even in the setting of pretransplant portal vein thrombosis, the left renal vein provides adequate inflow and likely also adequate mesenteric venous drainage. Michael J. Englesbe, M.D. Amit K. Mathur, M.D. Seth A. Waits, M.D. John C. Magee, M.D. Section of Transplant Surgery Department of Surgery University of Michigan Ann Arbor, MI

Modified technique for aortic cross‐clamping during liver donor procurement

Undue tension on the donor vessels during organ procurement is associated with intimal dissection, which can form the nidus for the thrombosis of the hepatic artery (HA) and graft loss. According to the US OPTN database, 143 grafts were discarded in the last 15 yr due to vascular damage during procurement. The most common technique to expose the supraceliac aorta is dissection between the left lateral segment of the liver and the esophagus-stomach. In obese donors, due to restricted space and in pediatric donors where the vessels are very delicate and this space is very small, the replaced or accessory left HA(R/A LHA) is prone to damage if approached conventionally. We describe a technique for the exposure of the supraceliac aorta in which the aorta is approached from the left side behind the gastroesophageal junction that does not require division of the gastrohepatic ligament. From May 2007 to May 2013, 104 liver procurements were performed. Eighty-nine (85.6%) were adults, and 15 (14.4%) were pediatric donors. Twenty-three (22.1%) had R/A LHA. No donor organ suffered any damage. One adult recipient with R/A LHA suffered HA thrombosis not related to it. In summary, this technical modification offers improved safety during cadaveric procurement and increases the ease.

Occipital pial synangiosis

Indirect revascularization techniques for posterior circulation moyamoya are infrequently described in the literature given the relative rarity of the disease process, particularly in the best candidates for indirect approaches-children. We present a detailed, illustrated video demonstration of the occipital pial synangiosis procedure performed in a 5-year-old child. The specific advantages of the pial synangiosis technique-suturing the donor vessel to the pia and a wide arachnoidal opening-can be successfully applied to posterior circulation indirect revascularization. • Perioperative hydration and aspirin limit the risk of perioperative stroke. • Pain control and maintained normocapnea limit the risk of perioperative ischemic events. • The posterior auricular artery may be an alternative donor vessel. • The donor vessel is dissected from distal to proximal; forceps protect it during skin incision. • The donor vessel is dissected along a generous length to minimize tension. • Coagulation of the dura is limited as meningeal vessels may serve as synergistic collaterals. • A wide arachnoidal opening facilitates the ingrowth of collateral vessels. • Suturing the donor vessel to the pia ensures it remains well apposed to the brain surface. • The dura is left open to encourage ingrowth of collateral vessels and limit tension on the donor vessel. • EEG monitoring is a crucial adjunct.

Angioplasty Using Covered Stents in Five Patients With Symptomatic Pulmonary Artery Stenosis After Single-Lung Transplantation

After lung transplantation, pulmonary artery stenosis (PAS) may occur at the anastomotic site, resulting in poor graft function and hypoxemia. Surgical repair has been the standard-of-care, although percutaneous angioplasty with stent insertion has been performed in patients unsuitable for surgery. We summarize our experience of pulmonary artery stent-graft placement in transplant recipients who were also fit for surgical repair. Retrospective review of five cases of single-lung transplant recipients (4 male, 1 female, median age 61 years) who underwent percutaneous angioplasty and insertion of stent-graft for severe PAS. Balloon-expandable stent-grafts were used that were tailored to the donor and recipient vessel diameters. Stenosis was diagnosed with computed tomography angiography at a median of 44 days (range 22-84) after transplantation. All stent placements were technically successful. There was only one periprocedural complication, a haemothorax that was drained. In four patients, the angioplasty improved the lung function; relative graft perfusion (as assessed by quantitative lung scintigraphy) improved by 26 % (IQR 13-37); and SpO2 improved by 8 % (IQR 4-9). Percutaneous angioplasty using stent-graft is a minimally invasive, safe, and efficacious procedure for treatment of posttransplantation PAS and should be considered as an alternative to surgery even when the patient is considered fit for surgical repair.

Abstract T MP30: Cerebral Arteriogenesis and Angiogenesis: Distinct Angioarchitecture of Innate and EDAS Collaterals in Intracranial Arterial Steno-Occlusive Disease

Introduction: Patients with ICASD form various degrees of collateralization. However, those collaterals fail over time contributing to symptom progression. Indirect revascularization via encephaloduroarteriosynangiosis (EDAS) establishes collateral flow through new vessels formed from external carotid branches in both moyamoya disease (MMD) and non-moyamoya (NM) ICASD. We hypothesize that the EDAS neovascularization differs in terms of angioarchitecture when compared to spontaneously formed collaterals in ICASD. Methods: We analyze pre and post-operative digital subtraction angiograms (DSA) of patients enrolled in a prospective trial of EDAS surgery using ImageJ software (http://imagej.nih.gov/ij). Angioarchitectural differences between innate and post-EDAS collaterals were evaluated by comparing their branching angioscore (BA) and artery tortuosity index (ATI). Results: Images from 26 patients, ages 4 to 84 (mean: 37 SD+/-19.5) were evaluated. Patients included 13 MMD and 13 NM-ICASD. Postoperative mean DSA time was 14 months. Post-EDAS collaterals had significantly higher BA and lower ATI than innate collaterals (BA: 9.8 vs. 5.5 and ATI 110 vs. 167 [p&lt;0.001] respectively). Subgroup analyses for patients with MMD and NM-MMD demonstrated the same pattern with higher BA for post-EDAS collaterals and lower ATI for innate collaterals (MMD: BA: 9.6 vs. 5.2, and ATI 107.7 vs.176.5, NM-ICASD: BA: 9.9 vs. 5.8, and ATI: 153.7 vs.115.4 p≤0.01). Type of ICASD, age, or time after angiography did not affect the indexes. Conclusions: Collaterals formed after EDAS differ in angioarchitecture to innate collaterals in MMD and NM-ICASD. Morphological differences are consistent with two distinct mechanisms of vessel formation: innate collaterals formed by arteriogenesis display high tortuosity and low branching as expected by a shear stress process acting on pre-existing conduits. Conversely, post-EDAS collaterals have higher branching and lower tortuosity as expected in a process of angiogenesis in which collaterals form through sprouting and splitting from the donor vessels.

2013 ESC guidelines on the management of stable coronary artery disease. The Task Force on the management of stable coronary artery disease of the European Society of Cardiology

Despite significant progress, chronic total occlusion (CTO) percutaneous coronary interventions (PCI) are often challenging and carry increased risk of complications. We present a highly complex CTO PCI case that was successfully completed despite numerous complications (perforation, donor vessel closure, stent loss, guide extension tip fracture, access site bleeding and cardiac arrest) to highlight the importance of appropriate patient selection, pre-procedural planning, comprehensive patient-centered risk/benefit discussion, and prompt recognition and treatment of intra-procedural complications.

STA-MCA/STA-PCA Bypass Using Short Interposition Vein Graft.

Superficial temporal artery (STA) is the mainstay of donor vessels for extra-intracranial bypass (EC-IC bypass) in cerebral revascularization. However, the typically used STA frontal or parietal branch is not always adequate in its flow-carrying capacity. In the present study, we provide an update on an alternative strategy: the use of the STA main trunk as a donor vessel, with a short vein interposition graft. Seven patients in whom the STA main trunk was used as a donor site for anastomosis of a short interposition vein graft were included. The grafts were implanted into the M2 of the middle cerebral artery for adjunctive treatment of IC anterior wall blood-blister aneurysms in two patients, for revascularization of an internal carotid artery occlusion in one patient, into the P2/3 of the posterior cerebral artery (PCA) for adjunct treatment of complex PCA aneurysms in three patients and into the P3 of PCA for adjunct treatment of basilar artery (BA) trunk giant aneurysm in one patient. All the bypasses were patent. Intraoperative flow measurements confirmed a moderate flow-carrying capacity of the STA main trunk-interposition short vein graft (20-50 ml; mean 43 ml/min). The STA main trunk has a larger diameter than the distal branch; therefore, it would be expected to have a significantly higher flow capacity than its branches. STA main trunk to proximal MCA/PCA bypass using short interposition vein grafts can provide sufficient blood flow, and may be a reasonable alternative to ECA to MCA/PCA bypass using long vein grafts.

Frequency and outcomes of aortocoronary dissection during percutaneous coronary intervention of chronic total occlusions

Aortocoronary dissection can complicate percutaneous coronary intervention (PCI) of chronic total occlusions (CTOs). We retrospectively examined the frequency and outcomes of aortocoronary dissection among 336 consecutive CTO PCIs performed at our institution between 2005 and 2012 and performed a systematic review of the published literature. Aortocoronary dissection occurred in six patients (1.8%, 95% confidence intervals 0.7%, 3.8%). All aortocoronary dissections occurred in the right coronary artery (CTO target vessel in five patients and donor vessel in one patient). The baseline clinical characteristics of patients with and without aortocoronary dissection were similar. Compared to patients without, those with aortocoronary dissection were more likely to undergo crossing attempts using the retrograde approach (25% vs. 67%, P = 0.036) and experience a major complication (2.4% vs. 33.3%, P = 0.008). Technical and procedural success rates were similar in both groups. Of the six patients with aortocoronary dissection one underwent emergency coronary bypass graft surgery (CABG), four were treated with ostial stenting, and one was treated conservatively without subsequent adverse clinical outcomes. Systematic literature review provided 107 published cases of aortocoronary dissection during PCI, that occurred mainly in the right coronary artery (74.8%) and were treated with stenting (49.5%), emergency CABG (29%), or conservatively (21.5%). Aortocoronary dissection is an infrequent complication of CTO PCI and although it can be treated with stents in most patients, it may infrequently require emergency CABG.

Flow-Through Flap for Salvage of Fibula Osseocutaneous Vascular Variations: A Surgical Approach and Proposed Modification of Its Classification

The osseocutaneous fibula free flap is commonly used in mandibular reconstruction. Clinically important anatomic variants of the donor vessels have been reported. The authors describe a rare variant encountered while raising an osseocutaneous fibula flap. The fibula was supplied by the peroneal vessels and the overlying skin paddle was supplied by musculocutaneous perforators arising from the posterior tibial vessels. By raising 2 separate free flaps and configuring them in microvascular series with the fibula acting as a flow-through flap, the reconstruction was successful. Although the anatomic variant has been described, the authors' approach to it has not. The benefits of this method over other options include preservation of a skin paddle for monitoring and watertight oral closure and a long pedicle to the skin paddle permitting a wide arc of movement. The authors suggest a modification to the existing classification of perforators to the lateral leg skin to guide intraoperative decision making.

Pectoralis Major Myocutaneous Flap for Reconstruction of Circumferential Pharyngeal Defects

A 270-degree partially tubed pectoralis major myocutaneous flap (PMMF) is an excellent option for total circumferential pharyngoesophageal defects in patients who are not candidates for more complex reconstructions. Patients undergoing circumferential pharyngoesophageal reconstruction with partially tubed PMMF were reviewed. End points were stricture, fistula, resumption of oral intake, perioperative death, and recurrence. Eleven patients underwent 270-degree PMMF for reconstruction: 6 (55%) were men and 5 (45%) were women (mean, 62 years; range, 42-78 years). Three patients (27%) developed fistulas and 2 (18%) developed stenosis. Ten patients (91%) were able to resume adequate nutrition via oral intake. There were no perioperative deaths. Patients with severe comorbidities, metastatic disease, a lack of donor vessels, or a potentially hostile abdomen may not be ideal candidates for free tissue transfer. For these patients, partially tubed PMMF using the prevertebral fascia provides a reliable alternative for reconstruction with excellent functional results.