bluuebunny/crossref_metadata_2025 huggingface dataset:
Improved Reliability of Post-Operative Ventricular Pacing by Use of Bipolar Temporary Pacing Leads
Authors: Yiu Patrick , Tansley Patrick , Pepper John R.
Published: September 2024

The study compared the clinical reliability of using a bipolar epicardial wire (6495, Medtronic) over a unipolar type (FEP15, Ethicon) for post-operative pacing in coronary artery surgery. Atrial and ventricular wires of both types were implanted in 18 patients. Sensitivities and pacing thresholds were tested for 5 consecutive days. Results show that pacing thresholds were better maintained with the bipolar wire in both atria and ventricles. However, sensing failures were frequent in the atrial position (34% vs 9.3% compared with unipolar). By contrast, in the ventricle, no sensing failures occurred (0% vs 17.6% compared with unipolar). Furthermore, sensing magnitude was significantly better (11.13±1.32 vs 5.65±0.53 mV, P< 0.001). We conclude that a single 6495 bipolar wire is effective for temporary ventricular pacing, whilst double unipolar wires remain a useful strategy for securing atrial sensing and pacing.
The Utility of the VCS Clip for Creation of Vascular Access for Hemodialysis: Long-Term Results and Intraoperative Benefits
Authors: Schild A. Frederick , Pruett Christopher S. , Newman Martin I. , Raines Jeffrey , Petersen Floyd , Konkin Taylor , Kim Peter , Dickson Cindy , Kirsch Wolff M.
Published: September 2024

The purpose of this study was to compare the effectiveness of the VCS® vascular clip approximating system for the creation of hemodialysis access fistulas. 173 new vascular accesses were created, 92 prosthetic grafts and 81 autologous fistulas over a 40-month period. 50 sutured and 42 clipped fistulas comprised the prosthetic graft series, and 33 sutured and 48 clipped cases the autologous series. Risk factors associated with access patency were correlated and the primary patencies compared in the suture versus clipped group. A significant improvement in primary patency was noted for the clipped prosthetic group at all time points studied, with a positive trend also noted for clipped autologous fistulae.

Conclusions:

The vascular clipping system (the VCS system) provides both long-term and immediate advantages for vascular access construction. Clips have been used successfully to treat seven consecutive patients with upper extremity arterial steal syndrome without the technical difficulties associated with traditional methods of repair.
Impact of Nonpenetrating Clips on Intimal Hyperplasia of Vascular Anastomoses
Authors: Berman S. S. , Kirsch W. M. , Zhu Y. H. , Anton L. , Chai Y.
Published: September 2024

Non-penetrating, arcuate-legged titanium clips create an interrupted, non-penetrated, yet compliant vascular anastomoses that is associated with significantly reduced anastomotic neointimal hyperplasia. Recent experimental and clinical studies provide evidence that the non-suture alternative changes the biology of vessel-to-vessel and graft-to-vessel connections that reduces the stimulus for hyperplasia at a number of critical points in the response to injury schema. The compliant, “blood-tight” characteristics of clipped vascular reconstructions are associated with no endothelial injury or intraluminal foreign body, minimal platelet aggregation and laminal flow. Clinical applications including vascular access, femoropopliteal bypass, and closure of carotid endarterectomies are remarkable for the absence of restenosis and preserved anastomotic patency.
Vena Caval Filter Placement by Intravascular Ultrasound
Authors: Matsuura John H. , White Rodney A. , Kopchok George , Nishinian Gary , Woody Jonathan D. , Rosenthal David , Clark Michael D.
Published: September 2024

Objective:

Placement of vena caval filters under fluoroscopic surveillance incurs significant expense and potential risks associated with the transportation of critically ill patients. Intravascular ultrasound (IVUS) allows direct intraluminal visualization of the vena cava and the renal veins. The purpose of this study is to evaluate the accuracy of vena caval filter placement under IVUS in an animal model.

Methods:

Fifteen Simon-Nitinol venal cava filters (C.R. Bard, Inc., Covington, GA) were placed under IVUS guidance into four anesthetized sheep. Twelve were placed transfemorally, and three were placed transjugularly. Accuracy of placement was confirmed with fluoroscopy by measurement between the filter tip and the targeted side branch.

Results:

The vena caval filters placed femorally averaged 0.33±0.42 cm distance from the target vein side branch. Jugular approach filter placement was less accurate. Although two out of three filters placed from the jugular vein were correctly positioned, the distance from the target vein side branch was much greater averaging 2.5±1.04 cm.

Conclusion:

Femoral placement of vena caval filters under IVUS is extremely accurate. The transjugular route, however, was technically challenging and standard fluoroscopic vena caval filter placement appears to be more appropriate. Our success with the femoral approach merits further clinical investigation in the use of IVUS for critically ill patients that would benefit from bedside vena caval filter placement.
The Impact of Ischaemic Preconditioning on Spinal Cord Blood Flow and Paraplegia
Authors: Ueno Tetsuya , Chao Zhi-Li , Okazaki Yukio , Itoh Tsuyoshi
Published: September 2024

Purpose:

We investigated the effect of ischaemic preconditioning (IP) on ischaemic spinal cord injury in a rabbit model.

Methods:

Fourteen rabbits were divided into IP and control groups of seven rabbits each. We repeated 3-min clamping of the infrarenal abdominal aorta and 3-min reperfusion twice (preconditioning), followed by 15 min clamping in the IP group. In the control group, the aorta was clamped for 15 min without preconditioning. Lumbar cord blood flow and systemic blood pressure were measured until 3 h of reperfusion. Another 14 rabbits underwent the same procedures with or without IP and neurologic status was assessed on the second postoperative day.

Results:

The percent change in lumbar cord blood flow after reperfusion was significantly greater ( P = 0.013) in the IP group despite lower mean blood pressure. There was no significant difference in overall neurologic status ( P = 0.461) but the incidence of spastic paraplegia in the IP group was lower (14%. 1/7) than that of control group (43%. 3/7).

Conclusion:

IP increased postischaemic lumbar cord blood flow and contributed to lower incidence of spastic paraplegia.
Is Deep Hypothermia Necessary for Unilateral Antegrade Cerebral Perfusion during Circulatory Arrest? A Magnetic Resonance Study in a Pig Model
Authors: Ye Jian , Dai George , Yang Luojia , Sun Jiankang , Summers Randy , Deslauriers Roxanne
Published: September 2024

Objective:

Localized 31P magnetic resonance spectroscopy (MRS) was used to investigate whether unilateral antegrade cerebral perfusion (U-ACP) could maintain normal energy metabolism and intracellular pH (pHi) in both hemispheres of the brain during deep (15°C) and moderate (28°C) hypothermic circulatory arrest (HCA).

Methods:

Eleven pigs were exposed to 120 min of U-ACP during HCA at 15°C (group I, n = 6) or 28°C (group II, n = 5), followed by 60 min of cardiopulmonary bypass (CPS) at 37°C. Localized 31P MR spectra were acquired every 30 min. Histopathology was performed at the completion of each experiment.

Results:

MR recorded no changes in energy metabolites (phosphocreatine and ATP), or pHi during U-ACP in either group, and no significant differences were found in any of the energy metabolites or pHi between the left and right hemispheres. Histopathology showed no significant morphological changes in the neurons.

Conclusions:

During either deep or moderate HCA, unilateral ACP through the right axillary artery prevents ischemic events in both hemispheres of normal pig brains. Deep hypothermia may not be necessary when using U-ACP. Crown Copyright
Sympathectomy: Quo Vadis?
Authors: Barnes R. W.
Published: September 2024

This paper reviews the evolution of sympathectomy in the management of vascular disease, hyperhidrosis and reflex sympathetic dystrophy over the past 26 years. The average general surgery resident has never been exposed to the procedure. The author feels that sympathectomy should be part of the armamentarium of vascular surgeons. An understanding of physiologic screening tests is necessary for the proper selection of patients who may benefit from sympathectomy. There has been a progressive decline in the number of publications on sympathectomy during this period. While the procedure is less commonly performed for vascular disease, sympathectomy remains a useful treatment for uncontrolled hyperhidrosis and for reflex sympathetic dystrophy.
Blood Flow in the Internal Carotid Artery and Velocity in the Middle Cerebral Artery during Carotid Endarterectomy
Authors: Magee T. R. , Davies A. H. , Baird R. N. , Horrocks M.
Published: September 2024

A stenosing atherosclerotic plaque of the internal carotid artery acts as a source of emboli and may impede flow. The contribution made by a stenosed carotid artery to cerebral perfusion is unclear. This study examined blood flow in the internal carotid artery and a comparison was made with the effect of clamping on flow velocity in the middle cerebral artery. Some 50 patients were assessed before carotid endarterectomy by preoperative duplex scanning, triplanar arteriography and transcranial Doppler ultrasonography. At operation, maximal flow in the internal carotid artery was measured using a Doppler flowmeter and flow velocity was monitored by transcranial Doppler. No correlation was found between the degree of stenosis and resting flow velocity. Mean flow in the internal carotid artery in patients with >90% stenosis was significantly lower than those with lesser stenoses ( P < 0.01). However, a mean minimal blood flow of 141 ml/min passed through the >90% stenoses. The effect of internal carotid artery clamping on flow velocity was similar irrespective of the degree of stenosis. In patients with >90% stenosis, the internal carotid artery continues to make an important contribution to cerebral perfusion.
Glasgow Aneurysm Score
Authors: Samy A. K. , Murray G. , MacBain G.
Published: September 2024

A clinical prognostic scoring system for patients with abdominal aortic aneurysm and audit of the sequelae of a sample population in Glasgow, are described. Randomly selected case notes of 500 patients, representing 41.6% (500 of 1202) of the total population treated in Glasgow hospitals with general surgical units (as opposed to vascular units) between 1980 and 1990, were examined for risk factors. These were then related to the operative and postoperative hospital mortality. Initial univariate analysis showed the outcome to be significantly influenced by the following factors: age ( P = <0.01), rupture ( P = <0.001), shock ( P = <0.001), myocardial disease ( P= 0.08), cerebrovascular disease ( P= 0.03), renal disease ( P= 0.03) and size of the aneurysm ( P = 0.06). Using multivariate analysis, the following independent risk factors were identified: age ( P = 0.02). shock ( P = <0.001). myocardial disease ( P = 0.02), cerebrovascular disease ( P = 0.02) and renal disease ( P = 0.003). Rounding of the regression coefficients created a simple risk score: risk score = (age in years) + (17 for shock) + (7 for myocardial disease) + (10 for cerebrovascular disease) + (14 for renal disease). Subsequent evaluation of the scoring system showed that the mortality rate increases in proportion to the score. Other findings are analysed and discussed.
Use of the Greenfield Filter in Patients with Major Trauma
Authors: Rosenthal D. , McKinsey J. F. , Levy A. M. , Lamis P. A. , Clark M. D.
Published: September 2024

Patients with major trauma often cannot be given the benefit of preventive measures such as pneumatic compression boots and low-dose heparin against pulmonary embolism. The Greenfield filter is accepted as a safe and effective method of prophylaxis of this complication. The aim of this study was to evaluate the efficacy of placement of the Greenfield filter in 161 patients with major trauma. Between January 1984 and July 1988, 94 patients with an injury severity score (ISS) of >16 were treated. This score is predictive of a mortality rate of at least 10% and defines major trauma based on anatomic injury. Some 20% (19 of 94) of these patients developed deep vein thrombosis despite standard prophylactic measures and 8% (eight of 94) suffered pulmonary embolism, two of which were fatal. Pulmonary embolism occurred without antecedent evidence of deep vein thrombosis in another 15% of patients (14 of 94), three of which caused death. From August 1988 until July 1992, of 67 other patients with an ISS > 16, 13% (nine of 67) developed deep vein thrombosis and 1% (one of 67) had a pulmonary embolism; this was not statistically significant ( P > 0.25). Of these 67 patients who were considered to be at high risk of pulmonary embolism, because of a contraindication to anticoagulation or physical impediment to sequential compression boots, 29 had prophylactic placement of a Greenfield filter. No pulmonary emboli occurred in these patients. During long-term follow-up (mean 32.8 (range 4–58) months), 84% of the surviving patients (21 of 25) underwent duplex ultrasonography of the inferior vena cava; patency of the vessel was confirmed in all patients. Placement of the Greenfield filter in this series was associated with minimal morbidity, and in all patients it prevented pulmonary embolism and the inferior vena cava remained patent. Placement of a prophylactic Greenfield filter seems appropriate in high-risk patients with major trauma involving lower extremity/pelvic fractures and multiple system injury for whom standard prophylaxis of deep vein thrombosis is not possible.
End-To-End Arteriovenous Fistula for Chronic Haemodialysis: 11 Years' Experience
Authors: Simoni G. , Bonalumi U. , Civalleri D. , Decian F. , Bartoli F. Griffanti
Published: September 2024

Between January 1979 and December 1989, an end-to-end arteriovenous fistula for chronic haemodialysis was performed at the anatomical snuffbox in 140 patients with a mean age of 51 (range 14–81) years and at the wrist in 248 with a mean age of 53 (range 19–83) years. The choice of site depended on the characteristics of the vessels and on the arterial blood pressure. No operative mortality, major complications or side effects occurred. The primary median patency for the arteriovenous fistula at the anatomical snuffbox was 36 months with a patency rate of 77.3% at 1 year, 36.3% at 5 years and 18.9% at 10 years. For the arteriovenous fistula at the wrist the median patency was 64 months and the patency rate 75.5% at 1 year, 54.5% at 5 years and 30.7% at 10 years. The higher incidence of thromboses in the patients with a fistula in the snuffbox may reflect an excessive enthusiasm for this technique because of initially promising results.
Aortic Sepsis from an Appendiceal Abscess
Authors: Mostovych M. , Johnson L , Cambria R. P.
Published: September 2024

A 75-year-old man with infection in a pre-existing abdominal aortic aneurysm secondary to an appendiceal abscess is described. A single similar case has been reported in the English literature. Appendicitis was diagnosed at exploration. In both cases, the appendix was located in a retroileal position in the retroperitoneum, thereby allowing tracking of the abscess to the aneurysm wall. Resection and extra-anatomic vascular reconstruction were curative.
Pedicled Muscle Flaps in the Management of Infected Aortofemoral Grafts
Authors: Gomes M. N. , Spear S. L.
Published: September 2024

Graft infection, although uncommon, is a serious complication of reconstructive vascular surgery, associated with a high mortality and limb loss in a large percentage of the survivors. Although débridement and drainage, specific systemic antibiotics, removal of the entire infected graft and revascularization by extra-anatomic bypass are the general principles of management, this technique has its limitations and in certain circumstances is not feasible. The use of well-vascularized autogenous tissue as coverage of infected grafts has been successful in the lower extremities, with graft and limb salvage, but not when the infection extends above the inguinal ligament. Instances where the infection at the inguinal area extends retrograde along the limb of the aortofemoral graft represent a greater therapeutic challenge. In two instances, a dual muscle flap was used successfully to cover the exposed prosthesis after complete débridement of the perigraft granulation tissue. Sartorius and rectus femoris muscles, with their blood supply, were mobilized and rotated to cover the distal anastomosis and the retroperitoneally exposed graft respectively, with primary wound closure. All flaps survived and the patent grafts were salvaged. There was no long-term functional deficit from the transposition of these muscles. Pedicled muscle flaps appear to be a well-tolerated method of achieving autogenous tissue coverage of an infected graft in the groin, and retroperitoneal portions and should be considered a satisfactory alternative when the traditional methods of management cannot be applied.
Retroperitoneal Caval Filter as a Source of Abdominal Pain
Authors: Goldman K. A. , Adelman M. A.
Published: September 2024

A patient with a Mobin-Uddin vena caval filter placed 10 years earlier was referred with abdominal pain, nausea, anorexia and weight loss. Diagnostic studies confirmed that the filter was in an extracaval position in the retroperttoneum, with the filter struts impinging on the right kidney, duodenum and colon. Following surgical removal of the filter the patient is now symptom-free with good appetite and weight gain.
Early and Long-Term Results of Cardiac Surgery in Dialysis Patients
Authors: Blum U. , Skupin M. , Wagner R. , Matheis G. , Oppermann F. , Satter P.
Published: September 2024

Cardiac surgery in patients receiving dialysis has a high mortality and morbidity. Early long-term results have been analysed following various cardiac operative procedures. Between 1981 and 1992, 40 patients, of mean age 55.7 (range 31–71) years underwent cardiac surgery. Procedures included coronary artery bypass grafting (20 patients), aortic valve replacement (six), mitral valve replacement (four), aortic valve or mitral valve plus coronary artery bypass grafting (one each), aortic plus mitral valves (two), heart and renal transplantation (one each), atrial septal defect closure (one) and pericardial decortication (three). Before surgery, patients were in the New York Heart Association (NYHA) classes II (5%). III (52.2%) and IV (42.5%). The operative mortality rate was 15%; survivors were in NYHA classes I (3%), II (88.2%) and III (8.8%). There were 11 late deaths. Follow-up at a mean of 35 (range 1–93) months showed actuarial survival rates of 91% (1 year) and 69% (5 years). After coronary artery bypass grafting, survival rates were 95% (1 year) and 72% (5 years). Survivors were in NYHA classes I (4.7%), II (85.5%) and III (9.5%). Cardiac surgery in dialysis patients is associated with an acceptable hospital mortality; quality of life in long-term survivors is increased. Hence, surgical treatment is advocated in patients with symptomatic heart disease. Early diagnosis and surgical intervention in NYHA class II patients may lead to a lower perioperative mortality.
The Use of Polyglyconate in Surgery of Congenital Heart Defects: Comparison with Polypropylene
Authors: Szufladowicz M. , Horvath P. , Honek T. , Stark J.
Published: September 2024

Absorbable suture material has several theoretical advantages in operations for congenital heart defects performed in infancy. This study compares handling characteristics of absorbable polyglyconate (Maxon) and non-absorbable polypropylene used in a variety of operations for congenital heart defects. There was no difference in mortality and morbidity between the two groups (50 patients each). Satisfactory tensile strength was noted in both groups. Maxon had more suppleness and first throw holding but more tissue drag when compared with polypropylene. Maxon was considered to be a suitable suture material in operations for congenital heart defects when the use of absorbable material is indicated.
Holographic Interferometry: A New Technique for in Vitro Investigations of Prosthetic Heart Valves
Authors: Geiger A. W. , Zarubin A. , von Bally G. , Scheld H. H.
Published: September 2024

At present there are many different prosthetic models available for heart valve replacement. Postimplant dysfunction resulting from material failure has been reported in several prostheses. The prime cause of these defects is hidden abnormalities in the valve construction or materials. In order to detect these defects before implantation, preoperative non-destructive testing of individual valves is proposed. For this purpose, holographic interferometry has been applied which is a non-contact, non-destructive, highly sensitive, three-dimensional measurement technique. Samples of different types of prosthetic heart valve, both mechanical and biological, were mounted in a specially developed test chamber with optical access from four sides. The valves were loaded with a static liquid pressure of 2.5–15 kPa. Deformations of the valves as a result of small pressure differences (0.5–15% of the static pressure) applied between two exposures were recorded by double-exposure holography. A fringe pattern superimposed on the image of the valve reconstructed from the hologram clearly indicates the presence of defects in the valve material.
Radiopharmaceutical Uptake as a Marker of Sternal Blood Supply following Internal Mammary Artery Harvesting
Authors: Rivas L. F. , Hawkins T. , Morritt G. N. , Behl R. P. , Griffin S. C. , Brown A. Hedley
Published: September 2024

To evaluate the impact of internal mammary artery harvesting on sternal blood supply after open heart surgery, a conventional bone scan was performed 7 days after operation in 30 patients. After administration of 370 MBq of technetium 99 m-medronic acid complex, imaging was carried out at the level of the sternum and including the humerus as a reference. A quantitative analysis of uptake (sternum/humerus uptake index) was performed and compared in three different groups of patients: group A, ten patients who had only vein grafts or valve surgery; group B, ten patients with single internal mammary artery harvesting; and group C, ten patients with bilateral internal mammary artery harvesting. These results were compared with 24 non-surgical subjects as a control (group D). Although intervention had a significant influence in raising the uptake index of the surgical groups (A = 3.34; B = 3.09 and C = 3.48) when compared with normal subjects (D = 2.45) ( P<0.01), there was not a statistically significant difference among the three surgical groups ( P>0.05). It was concluded that the vascular supply of the sternum is not entirely dependent upon the internal mammary arteries and that mobilization of both vessels does not cause per se additional serious impact to the bone vascularization after midline sternotomy, at least beyond day 7 after operation.
Non-Invasive Doppler Technique for Detection of Flow Velocity in Left Internal Mammary Artery Grafts
Authors: Nasu M. , Takagi T. , Akasaka T. , Shinkai M. , Fujiwara H. , Sono J. , Okada Y. , Miyamoto S. , Nishiuchi S. , Shomura T.
Published: September 2024

The capability of Doppler to detect patency of left internal mammary artery grafts through the supraclavicular approach was evaluated. A total of 37 patients with a left internal mammary artery graft to the left anterior descending artery were divided into three groups, according to postoperative coronary angiographic studies. Group 1 comprised 20 patients with no significant stenosis of the left internal mammary artery and subtotal or total obstruction in the left anterior descending coronary artery proximal to the anastomotic site. There were ten patients with no significant stenosis of the left internal mammary artery and 75% stenosis of the left anterior descending coronary artery in group 2. Seven patients with significant stenosis of the left internal mammary artery formed group 3. Analysis of the flow velocity pattern in the left internal mammary artery graft Included: (1) systolic peak velocity (SPV), (2) diastolic peak velocity (DPV), (3) systolic time velocity integral (SI), (4) diastolic time velocity integral (DI), (5) diastolic peak velocity/systolic peak velocity and (6) diastolic time velocity integral/diastolic time velocity Integral + systolic time velocity integral. There were no significant differences in systolic peak velocity and systolic time velocity integral between the three groups. The diastolic peak velocity and diastolic time velocity integral were greater in group 1 than in groups 2 ( P<0.05, P<0.01) and 3 ( P<0.05). The diastolic peak velocity/systolic peak velocity and diastolic time velocity integral/diastolic time velocity integral + systolic time velocity integral ratios in group 3 were significantly smaller than in groups 1 and 2 ( P<0.01). However, there were no significant differences in both ratios between groups 1 and 2. These data show that the diastolic component of the flow velocity pattern of a patent left internal mammary artery graft is significantly predominant over the systolic component regardless of stenosis of the left anterior descending coronary artery proximal to the anastomotic site. It was concluded that native coronary flow competed with that of the left internal mammary artery to reduce graft flow in patients with < 75% stenosis in the proximal left anterior descending coronary artery as well as in those with higher diastolic peak velocity/systolic peak velocity and diastolic time velocity integral/diastolic time velocity integral + systolic time velocity integral ratios > 0.5 who possessed patent left internal mammary artery grafts.
Prosthetic Valve Endocarditis: Surgical Procedures and Clinical Outcome
Authors: Otaki M.
Published: September 2024

Over a period of 10 years, 25 patients underwent reoperation for prosthetic valve endocarditis. The basic procedure for surgical treatment differed depending on the presence or absence of annular ring abscess. Standard valve replacement was employed in 15 patients without annular ring abscess (three aortic, eleven mitral and one tricuspid). The ten other patients who had had partial destruction of the annulus underwent complex surgical treatment (six aortic, three mitral and one aortic and mitral). Complex operative techniques consisted of three different procedures, depending on the anatomical lesion in each patient. Aortic valve replacement was performed by subannular implantation with horizontal Dacron felt-supported mattress sutures through the ventricular septum, ventricular outflow wall muscles and base of the anterior mitral leaflet. A prosthesis with a polytetrafluoroethylene flange was used for mitral valve replacement to permit double suturing of the prosthesis and firm anchoring. Double valve replacement (mitral, aortic) with destruction of the fibrous skeleton was carried out using a composite graft consisting of a triangular-shaped Dacron patch and two Björk—Shiley valves. There were four operative deaths (16%; three who underwent standard valve replacement and one who had complex surgical treatment). In no case could the cause of death be related to the surgical procedure. These patients had had haemodynamic decompensation before operation and required urgent reoperation. Preoperative New York Heart Association functional class IV ( P< 0.05) and operative urgency ( P< 0.05) had a significant correlation with mortality. On the basis of these results, operative mortality can be improved if conditions leading to myocardial damage are prevented and proper reconstruction conducted.
Reoperative Cardiac Valve Surgery: A Multivariable Analysis of Risk Factors
Authors: Biglioli P. , Di Matteo S. , Parolari A. , Antona C. , Arena V. , Sala A.
Published: September 2024

From December 1983 to March 1992, of 1650 patients who underwent a cardiac valve procedure 41 (2.5%) underwent reoperation on prosthetic heart valves. The indications for reoperation were: structural degeneration (13 patients, 32%), non-structural dysfunction (nine patients, 22%), prosthetic valve endocarditis (seven patients, 17%), valve thrombosis (four patients, 10%), native valve pathology (three patients, 7%), aortic ascending pathology (five patients, 12%). The hospital mortality rate for mitral vale reoperation was 12% (two of 17) and for reoperation on the aortic prosthesis 26% (five of 19). No deaths occurred for associated mitral and aortic rereplacement (zero of five). The mortality rate for associated procedures was 24% (four of 17) versus 12% (three of 24) for isolated procedures. Preoperative and operative variables were analysed to determine risk factors for hospital mortality. New York Heart Association functional class, ascites, endocarditis and surgical timing had a univariate influence on operative mortality. The pulmonary capillary wedge pressure and preoperative creatinine level were also higher in non-survivors. Elective reoperation had a mortality rate of 7%, while that for emergency procedures was 38%. Multivariable analysis indicated a longer extracorporeal circulation time and the urgent-emergency status as predictors of mortality. Reoperation before severe hemodynamic impairment occurs is recommended.
Secondary Infrageniculate Bypass with Polytetrafluoroethylene
Authors: Petersen M. J. , Hines G.
Published: September 2024

Autologous saphenous vein is the preferred conduit for infrainguinal reconstructions. Patients requiring secondary infrageniculate bypass represent a challenging surgical problem. Often, patients requiring such surgery have had multiple bypass operations and lack usable saphenous vein. These patients may also be older and have complicated medical problems which may limit their total life expectancy. This report reviews 11 such patients who required secondary bypass procedures for limb salvage. All procedures were performed with thin-walled polytetrafluoroethylene (PTFE). No perioperative complications or deaths occurred. Four patients have subsequently died due to unrelated disease at 8, 12, 13, and 29 months after operation with clinically patent grafts. In the seven surviving patients, four grafts remain patent with a mean(s.d.) patency of 27(21) months. Three grafts occluded at 2, 4 and 20 months after surgery. By life table analysis, cumulative graft patency was therefore 68% at 24 months. It is concluded that in this high-risk population when no saphenous vein is available. PTFE may provide acceptable limb salvage when used in secondary infrageniculate reconstructions.
Prevention of Early Graft Infection with Rifampicinbonded Gelseal Grafts: A Multicentre Experimental Study
Authors: D'Addato M. , Curti T. , Freyrie A. , Agus G. B. , Bertini D. , Biasi G.
Published: September 2024

The possibility of increasing the resistance of a synthetic vascular graft to intraoperative or immediate postoperative bacterial contamination justifies the interest in methods such as antibiotic bonding or antibiotic soaking. On the basis of this experience and with the aim of testing the efficacy of such a graft, a multicentre experimental study on sheep to compare the susceptibility to infection of Dacron Gelseal grafts (control) versus rifampicin-bonded Dacron Gelseal grafts (treated) following the intravenous infusion of 107–108 cells Staphylococcus aureus was conducted. The grafts were implanted in both common carotid arteries of sheep. In a group of 11 animals (group A), a treated and a control graft were implanted in the same animal. In a group of four sheep (group B), only treated or control grafts were implanted in each animal. In group A, 36% of (four of 11) the treated grafts became infected versus 54% (six of 11) of the control prostheses. In group B, none of the treated grafts was infected by the inoculated pathogen, which, by contrast, infected 75% (three of four) of the controls. These observations confirm the recent interest aroused by the possibility of pretreating gelatin-coated Dacron grafts with rifampicin in the prevention of early graft infection.
Long-Term Cryopreservation of Autologous Veins in Rabbits
Authors: Faggioli G. L. , Gargiulo M. , Giardino R. , Pasquinelli G. , Preda P. , Fini M. , Corbascio M. , Stella A. , D'Addato M. , Ricotta J. J.
Published: September 2024

This study was undertaken to determine the effect of long-term cryopreservation on graft ultrastructure and endothelial cell viability in an animal model. The jugular veins from 12 New Zealand White rabbits were excised with a ‘no-touch’ technique and divided into four groups: control group (fresh veins); group 1, veins cryopreserved for 1 month; group 2, veins cryopreserved for 2 months; and group 3, veins cryopreserved for 3 months. Cryopreservation was accomplished by rapid freezing (−5°Cs−1 to −196°C) in a solution of 17.5% dimethylsulphoxide and 20% fetal bovine serum and by storage in liquid nitrogen. Veins were then implanted as a carotid autograft (three grafts/group). At the time of graft implantation a segment of the paired matched vein was perfusion-fixed and evaluated by scanning and transmission electron microscopy, whereas the remainder were subjected to endothelial cell culture techniques to determine cell viability. Autografts were removed 1 month after implantation and subjected to similar evaluations. Histological changes seen in cryopreserved veins were dependent on preservation time and included focal endothelial cell blebbing, cytoplasmic vacuolization and disruption of cell-to-cell contacts. Smooth muscle cells showed mithocondrial swelling. Patency was identical in all groups (66.6%). Explants at 1 month were similar in histological appearance to fresh veins with a smooth endothelial cell lining arranged longitudinally and intact cell junctions. Endothelial cells could be cultured from fresh veins and 1-month-old explants but not from the cryopreserved graft surface before implantation. The present technique of cryopreservation leads to some damage of graft architecture and loss of endothelial cell viability. However, these changes are reversed after 1 month of implantation at which time a viable cell lining is restored.
Persistent Sciatic Artery: Two Case Reports and a Review of the Literature
Authors: Ito H. , Okadome K. , Odashiro T. , Ishii T. , Funahashi S. , Komori K. , Sugimachi K.
Published: September 2024

Persistent sciatic artery (PSA) sometimes shows variant vascular symptoms such as chronic or acute limb ischaemia and a pulsatile mass in the buttocks caused by aneurysmal dilatation. This report presents two cases of surgically treated PSA that caused lower-limb ischaemia. The first patient, a 58-year-old man, showed acute limb ischaemia in the chronic clinical course, and thrombectomy and patch angioplasty were performed. The second patient, a 70-year-old woman, had an incomplete type of PSA without development of the femoral artery while complaining of a 10-year history of coldness and numbness in the left lower limb. A left common iliac to profunda femoris arterial bypass was performed. This is the second case of symptomatic incomplete PSA reported in the literature. This report also reviews 45 cases of PSA published since 1977. The diagnosis of PSA requires arteriography that includes the bilateral iliac systems. Femoropopliteal bypass and, in the case of sciatic artery aneurysm, a ligature of the sciatic artery are recommended for the surgical treatment of PSA.
Operative Management of a Persistent Sciatic Artery Aneurysm
Authors: Calleja F. , Jiménez M. A. García , Roman M. , Canis M. , Concha M.
Published: September 2024

A 60-year-old man with a painful pulsatile mass approximately 8 cm in diameter in the right buttock was diagnosed using angiography as having a complete unilateral persistent sciatic artery aneurysm. The lesion was obliterated by proximal and distal ligation of the sciatic artery at the pelvis and the adductor magnus canal. A femoropopliteal bypass was performed with inverted autologous saphenous vein. The residual mass was subsequently drained because of persistent symptoms. Postoperative recovery was good.
Protection against Spinal Cord Ischaemia: One-Shot Infusion of Hypothermic Solution
Authors: Ueno T. , Itoh T. , Hirahara K. , Sakai M. , Naitoh K.
Published: September 2024

The protective effect of a one-shot infusion of a range of low-temperature hypothermic solutions against spinal cord ischaemia was investigated. Forty rabbits were allocated into five groups each of eight animals. The abdominal aorta of each rabbit was clamped distal to the left renal artery, and also occluded for 30 min above the iliac bifurcation with an inflated 50-gauge French balloon catheter. Ringer's solution with lactate was infused through the catheter port distal to the balloon, at various temperatures (group I, uninfused control; group II, 33°C; group III, 23°C; group IV. 13°C; and group V. 3°C). The neurological status of the hind limbs was assessed on the second postoperative day using the criteria of Tarlov. A further eight rabbits underwent laminectomy at L2 or L3. Temperature probes were inserted into the spinal cord and the cord temperature monitored continuously during infusion in four rabbits from each of groups I and V. Spastic paraplegia occurred in five rabbits in group I, three in group II, and two in group III. Four rabbits in groups II and III, seven in group IV and all eight in group V showed complete recovery of neurological function. The infusion of 3°C solution achieved significantly lower spinal cord temperatures in group V after aortic clamping, compared with the temperatures in group I ( P< 0.001–0.005). It was concluded that protection against spinal cord ischaemia and prevention of postoperative paraplegia are promoted as the temperature of the hypothermic infusion solution is lowered.
Adjustment of Pulmonary Artery Banding by Mitral Valve Flow Velocity
Authors: Miyamura H. , Watanabe H. , Sugawara M. , Tatebe S. , Hayashi J. , Eguchi S. , Sato I.
Published: September 2024

In order to determine the tightness of the pulmonary artery band, Doppler echocardiography is used to assess mitral valve flow velocity, which is an indirect indicator of pulmonary blood flow. The band is tightened until the velocity decreases to 70% of the original maximal level. Additional adjustment of the constriction is then made to obtain reasonable arterial oxygen saturation, heart rate and ventricular contractility. Using this method, 12 consecutive patients underwent pulmonary artery banding with satisfactory results. This technique is simple but useful in obtaining optimum constriction of the pulmonary artery in congenital heart disease with excessive pulmonary blood flow.
Atrial Fibrillation following Myocardial Revascularization
Authors: Underwood M. J. , Weeresena N. , Arnold I. , Graham T. R.
Published: September 2024

Atrial fibrillation following coronary artery surgery is common, especially in elderly patients but despite numerous studies its pathophysiological basis is still incompletely understood. It is usually benign and self-limiting, but may be associated with haemodynamic compromise, prolonged hospitalization and embolic stroke. No risk factors (apart from age and preoperative (β-blocker withdrawal) have been shown to be associated with its occurrence. Conventional treatment is usually effective but no prophylactic regime has been identified. Until such a regime is found the incidence of atrial fibrillation following myocardial revascularization may only be reduced by continuing treatment in patients on β-blockers in the preoperative period and re-establishing this therapy after surgery.
Acute Postoperative Block of Mechanical Prostheses: Incidence and Treatment
Authors: Santé P. , Renzulli A. , Festa M. , Vitale N. , Mollo A. , Dialetto G. , De Luca L.
Published: September 2024

Acute intermittent postoperative block of mechanical prostheses is a rare and life-threatening complication; its incidence and treatment are not well defined. Between January 1975 and June 1991, 2839 mechanical prostheses were implanted using the same technique: mattress suture for mitral valve replacement and simple suture for aortic valve replacement. Prosthetic block occurred in eight patients: four following mitral valve replacement and four after aortic valve replacement. The blocked prosthesis was always a tilting disc valve (five Sorin, two Björk—Shiley and one Medtronic). The event occurred over a time interval of 6–48h (mean(s.d.) 17.3 (15.6)h). All patients having mitral valve replacement needed emergency prosthetic replacement. In aortic valve replacement, reoperation was necessary in two patients; the disc block disappeared in the others. All patients are alive with a follow-up ranging between 3 and 168 (mean 32.5) months. No structural failure was found in explanted prostheses leading to a diagnosis of extrinsic block. The overall incidence of this complication was 0.28% (eight of 2839); 0.24% (four of 1645) for mitral valve replacement and 0.33% (four of 1194) for aortic valve replacement respectively (n.s.). It was exclusively related to tilting disc valves (0.44%; eight of 1830) versus ball and bileaflets valve (0 of 1009). In mitral valve replacement reoperation on patients is mandatory; in aortic valve replacement patients the left ventricular pressure itself can overcome the prosthetic block. Attention should be paid to valve excision and suture technique as tilting disc prostheses are more vulnerable to extrinsic block. Furthermore, their use is contraindicated in redo operations and mitral valve replacement with total or partial preservation of mitral apparatus.
Importance of the Coronary Collateral Circulation for the Distribution of Anterograde and Retrograde Delivered Cardioplegic Solution in Aortocoronary Bypass Surgery: A Haemodynamic Study
Authors: Noyez L. , van Son J. A. M. , van der Werf T. , Knape J. T. A. , Gimbrère J. , van Asten W. N. J. C. , Lacquet L. K. , Flameng W.
Published: September 2024

The importance of coronary collateral circulation for homogeneous distribution of anterograde and retrograde delivery of cardioplegia was evaluated in 36 patients undergoing myocardial revascularization. All patients had three-vessel coronary artery disease, with a stenosis of the right coronary artery of at least 80%. The patients were randomized into two groups: group A ( n = 19) received anterograde delivered cardioplegic solution and group B ( n= 17) received retrograde. Both groups were further subdivided depending on the pathology of the right coronary artery, as evaluated on preoperative coronary angiography. In group A, ( n = 8) and group B1 ( n = 7) there was no visualization of collateral circulation from the left to the right coronary artery system, whereas in group A2 ( n =11) and group B2 ( n= 10) there was retrograde filling of the right coronary artery by collateral circulation. Right atrial pressure increased significantly ( P< 0.05) in group A, and was elevated in group A2. but not significantly (P= 0.07). By contrast, right arterial pressure decreased in groups B1 and B2. Analysis of the individual differences in the right atrial filling pressure showed a statistical significance between the two subgroups (group B1 −1.0(0.5) versus group B2 −1.8(1.1), P < 0.05), although the individual decrease of the right ventricular stroke work index was not significant. It is concluded that collateral circulation is important for an adequate distribution of anterogradely delivered cardioplegia and is also beneficial in cases of retrograde delivery.
Vein Harvest Ischemia: A Peripheral Vascular Complication of Coronary Artery Bypass Grafting
Authors: Gandhi R. H. , Katz D. , Wheeler J. R. , Gregory R. T. , Snyder S. O. , Gayle R. G. , Parent F. N.
Published: September 2024

Lower-extremity ischemia can lead to impaired healing of saphenous vein excision sites in patients with significant peripheral vascular disease (PVD). Five patients who required infrainguinal revascularization for wound necrosis of the harvest site after coronary artery bypass grafting are described. The male/female ratio was 2:3 with a mean age of 67 (range 45-87) years. The most commonly associated problems were insulin-dependent diabetes mellitus (80%) and congestive heart failure (60%). The saphenous vein was harvested from the thigh and leg in three patients and exclusively from the leg in the others. Manifestations of ischemia ranged from persistent ulceration to complete wound disruption threatening limb loss. Impaired healing was isolated to infragenicular wounds in all patients. Pedal pulses were not detected in any of the affected extremities. Determination of the ankle/brachial pressure indices (ABI) revealed values of < 0.5 in three affected limbs. Non-compressible vessels resulted in falsely raised ABI of > 1.0 in the remaining two limbs; however, Doppler waveform analysis in these patients demonstrated significant PVD. Aggressive wound care and antibiotic therapy were continued for mean of 9 weeks before operative intervention. Infrainguinal reconstruction included femoropopliteal (two), femorotibial (two) and popliteal-tibial bypass (one). Autologous arm and saphenous veins in addition to expanded polytetrafluoroethylene grafts were used effectively. Limb salvage and wound healing were achieved in 100% of the patients without untoward sequelae. It is concluded that unrecognized PVD in patients undergoing coronary artery bypass grafting can lead to significant morbidity. Patients at risk may be identified with a combination of history, physical examination and non-invasive testing. In limbs with ABI < 0.5 or significantly abnormal Doppler-derived waveforms, alternate sites of vein harvesting should be sought. Nonetheless, once wound necrosis develops as a result of vascular insufficiency, this study supports lower-extremity revascularization to achieve healing and limb salvage.
Primary Aortocaval Fistula
Authors: Ghilardi G. , Scorza R. , Bortolani E. , de Monti M. , Longhi F. , Ruberti U.
Published: September 2024

Twenty-two spontaneous aortocaval fistulas between an abdominal aortic aneurysm and the inferior vena cava were surgically treated in 27 years at one surgical unit. The incidence was 5.9% of ruptured abdominal aneurysms; the operative mortality rate of 36.4% compared with an overall mortality rate for ruptured abdominal aortic aneurysms of 34.9%. Among 10 subjects in shock on admission the mortality rate was 50% compared with 25% in non-shocked patients. Of the 22 patients one died at laparotomy from irreversible cardiac arrest; in the other 21 the procedure consisted of endoaneurysmal repair of the fistula which involved replacement of the aneurysm by a Dacron prosthesis after control of venous bleeding was achieved. No occurrence of paradoxical pulmonary embolism was reported. Multiple organ failure caused death in six cases; of these, four died as a result of acute renal failure. Severe preoperative anuric shock was recorded in five instances, with a mortality rate of 80%. compared to 25% for non-shocked subjects. Mortality was not improved by intraoperative autotransfusion; however, the incidence of severe shock was 55.5% in those patients treated by autotransfusion, compared with 38.5% in the standard blood replacement group.