bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative Analysis of Glutaraldehyde-Preserved Porcine Xenografts and Fresh or Glutaraldehyde-Treated Human Aortic Valves by Holographic Interferometry
Authors: Geiger A. W. , Zarubin A. M. , Deiwick M. , Asfour B. , Fahrenkamp A. , Hertel M. , von Bally G. , Scheid H.H.
Published: September 2024

Although calcification and degeneration are recognized as the main causes of bioprosthetic heart valve failure, the reasons for such failure are not well understood. Hidden tissue anomalies in the valves may be the origin of later calcification. Application of hologram interferometry for non-destructive testing enables the detection of such tissue anomalies. A comparative study by holographic interferometry of ten porcine bioprosthetic valves (seven Carpentier-Edwards SAV. two Biolmplant and one Valcor) with five human aortic valves before and after glutaraldehyde treatment is presented. Whereas irregularities were detected in the interferograms of eight out of ten bioprostheses, no similar distorted fringe pattern was found in the holographic interferograms of human specimens. The present results suggest that tissue abnormalities exist in standard bioprosthetic valves which are absent in human ones. These irregularities may be the origin of later calcification and valvular dysfunction.
Late Occlusion of Aortofemoral Bypass Graft: Surgical Treatment
Authors: Pedrini L. , Pisano E. , Di Paola M. Donato , Ballester A. , Magnoni F.
Published: September 2024

Surgical treatment for graft thrombosis is often difficult and its outcome is complicated by a high incidence of rethrombosis. The records of 803 patients (1261 limbs) treated with aortofemoral bypass graft for peripheral vascular disease were reviewed. Among these, 71 patients (63 men and eight women with a mean age of 60.2 years) needed an overall number of 125 reoperations. The mean follow-up was 6.3 years. Smoking was significantly higher in these patients, compared with those who were not reoperated on. Intimal hyperplasia was the most common lesion responsible for graft thrombosis. Before ‘redo’ surgery 20 patients with recent thrombosis received thrombolytic treatment; one was subsequently treated with percutaneous transluminal angioplasty and the others underwent reoperation. The best patency rates were achieved with reconstruction of the distal anastomosis with a graft interposition or with a patch angioplasty. Isolated thrombectomy was complicated by early rethrombosis in 53.3% of cases. The overall amputation rate was 14%, the operative mortality rate 5.6%, and the incidence of complications 16.8%. At follow-up a cumulative secondary patency rate of 81.7% at 5 years (74.5% at 10 years), a limb salvage rate of 80.5%, and a survival rate of 89.2% at 10 years were recorded. It is concluded that the only indications for redo surgery following graft thrombosis are severe limb ischaemia or disabling claudication.
Ex situ Repair of Complex Renal Artery Lesions
Authors: Lacombe M.
Published: September 2024

A total of 59 patients (from a personal series of 354) underwent ex situ repair of complex renal artery lesions. This series comprised 27 males and 32 females, of whom 15 were children and 44 adults, with ages ranging from 17 months to 70 years. The operated lesions were aneurysms with or without associated stenosis, spontaneous dissection, extensive fibrodysplasia and reoperations on the renal artery. In all patients, the kidney was exteriorized and cooled by perfusion of cold Collins' solution. The kidney was reimplanted after repair in either the loin or the iliac fossa. An arterial substitute was used in 42 patients. No mortality was observed. There were three cases of postoperative thrombosis of the repaired artery. Segmental thrombosis leading to partial atrophy of the kidney occurred in three patients. During long-term follow-up, one repeat stenosis and two fusiform dilatations of the venous autografts were observed. All other repairs (85%) were successful. Arterial hypertension in 46 patients was cured in 33 cases (72%) and improved in eight (17%). Renal function was improved after repair of severe stenotic lesions impairing renal blood flow restored normal circulation to the organ. Ex situ repair must be reserved for: (1) multiple lesions involving terminal branches of the renal artery for which prolonged circulatory arrest is required: and (2) lesions profoundly situated in the renal sinus that are difficult to treat by conventional surgery.
Arterial Injuries Associated with Lower-Extremity Fractures
Authors: Andrikopoulos V. , Antoniou I. , Panoussis P.
Published: September 2024

The records of 110 patients with arterial injuries of the lower extremities associated with bone fractures, and managed in the authors' vascular surgery clinic, were reviewed. The majority (72%) were young men; 66 had blunt and 44 penetrating arterial injuries. A total of 92 patients were treated by saphenous vein interposition grafting, 12 with composite grafts and six with polytetrafluoroethylene grafts. The limb salvage rate was 93%. All eight amputations were in neglected cases with arterial injury at the popliteal or infrapopliteal level and associated with muscle loss.
Diffuse Arterial Thrombosis in a Young Man with Elevated Lipoprotein(a) and Minimal Atherosclerosis
Authors: Levy P. J. , Gonzalez F. , Sheridant D. , Carter J. , Haynes J. L.
Published: September 2024

An increased incidence of premature atherosclerotic arterial occlusive disease was recently reported in young adults. This condition is characterized by early occurrence of severe symptoms, lower incidence of typical cardiovascular risk factors for atherosclerosis, different natural course of arterial disease vis-a-vis older population, and poor outcome of a standard treatment. This report describes a young man with aggressive arterial occlusive disease in the lower extremities and symptom-free occlusions of coronary and renal arteries in association with high levels of lipoprotein(a). Microscopic early atherosclerotic changes were noted in the occluded arteries of the amputated leg. Premature atherosclerotic arterial occlusive disease in young adults has different clinical and pathological patterns, necessitating a different approach for evaluation and treatment.
Concomitant Repair of Complete Atrioventricular Canal Defect and Transposition of the Great Arteries in an Infant
Authors: Roughneen P. , Mahmoudian M. H. , Ott D. A.
Published: September 2024

The case of an infant who was born with the rare presentation of complete atrioventricular canal defect and transposition of the great arteries is described. The patient underwent pulmonary banding at the age of 2 months, followed by concomitant arterial switch and repair of the atrioventricular canal defect at 20 months. Palliative banding allowed for the infant to grow and thus facilitated the later successful repair of these congenital defects.
Deep Venous Valve Reconstruction
Authors: Kistner R. L. , Eklof B. , Masuda E. M.
Published: September 2024

The place of deep venous valve reconstruction in the surgical management of the patient with chronic venous insufficiency has become clearer with collected experience over the past 25 years. The reasons to perform surgery in chronic venous disease and the specific rationale for deep venous repair are contrasted with the management of the same patient by medical means. A new classification of chronic venous disease has been developed and provides the basis for a more objective understanding of specific entities in the entire field of chronic venous symptoms. The requirements for diagnosis before reconstructive surgery are stringent and a diagnostic algorithm is discussed in the selection of candidates for deep venous reconstruction. The multiple surgical techniques for deep venous reconstruction include internal intravenous direct valve repair and extravenous tightening of the vein wall around the valve cusp. The results, of valve repair for primary valve incompetence are discussed in terms of long-term clinical results, long-term imaging results and long-term physiologic results as reflected by venous pressure examinations. It is becoming increasingly clear with the passage of time and the sharpening of our diagnostic skills that reflux Is the dominant cause of chronic venous insufficiency. The ability of surgical procedures to decrease reflux in a diseased extremity can be used to restore patients to their normal way of life free of pain, swelling and ulceratlon and, in the ideal case, free of the need for elastic support.
Improvement in Suction Catheter Efficiency and Safety in Arterial Operations
Authors: Jain K. M. , Simoni E. J. , Munn J. S.
Published: September 2024

The Blood Shield is a new device which has been developed to attach easily to the tip of a conventional suction catheter. Two experiments were performed to determine if the Blood Shield could limit the degree of splash which occurs during vascular graft flushing and whether it could increase the efficiency of a standard suction tip in collecting shed blood for autotransfusion. The results of the experiments indicate that the Blood Shield, when added to a conventional suction catheter, diminishes the amount of spray which may occur during anastomotic flushing. Secondly, it more effectively collects blood from a flushed anastomosis or arteriotomy in comparison with a suction catheter alone.
Normothermic versus Hypothermic Perfusion During Primary Coronary Artery Bypass Grafting
Authors: Christenson J. T. , Maurice J. , Simonet F. , Velebit V. , Schmuziger M.
Published: September 2024

Normothermic versus hypothermic cardiopulmonary bypass was evaluated in 1442 consecutive patients undergoing primary coronary artery bypass grafting (CABG). Group 1 ( n = 545) were operated on in moderate systemic hypothermia (rectal temperature 28°C) and group 2 ( n = 897) in normothermia (rectal temperature 37°C). Both groups had cold cardioplegic arrest (10°C) and local cooling of the heart with slush. Anaesthesia and operative techniques were identical in both groups. The mean age was 60 years; group 2 contained significantly more patients aged >65 years ( P< 0.05) and had more frequent emergency operations (P< 0.001) than group 1. Other preoperative patient characteristics were similar between groups. Aortic cross-clamping time was similar in both groups but cardiopulmonary bypass time was significantly longer in group 1 than in group 2 (97.9(28.8) versus 76.6(26.0) min, P< 0.001). Perioperative mortality rate was 3.3% in group 1 and 2.6% in group 2. The incidence of myocardial infarction was significantly higher in group 1 than in group 2 (2.0% versus 0.7%) Perioperative low cardiac output needing inotropic support was similar in both groups, but group 1 patients required more intra-aortic balloon insertions (4.6% versus 2.2%, P< 0.05). Lower incidence of postoperative ventricular arrhythmias, shorter intubation time and less transient renal failures were significant in group 2 compared with those in group 1 (P< 0.001), while re-exploration of bleeding, wound infections, pulmonary, neurological and gastrointestinal complications did not differ. Blood transfusion was less in group 2 (1.2(1.1) units, P< 0.001). On day 1 after surgery, serum creatinine, lactate dehydrogenase and creatine Phosphokinase values were increased in both groups but were significantly lower in group 2 (P< 0.001). Normothermic cardiopulmonary bypass combined with cold cardioplegic arrest is safe and provides sufficient cardiac and total body protection during primary CABG. Several of the adverse effects of hypothermia can be avoided, such as prolonged cardiopulmonary bypass time and ventilatory support, disturbed haemostasis and transient renal failure.
Hemodynamic Improvement in Hemorrhagic Shock by Aortic Balloon Occlusion and Hypertonic Saline Solutions
Authors: de Figueiredo L. F. Poli , Peres C. A. , Attalah A. N. , Romaldini H. , Miranda F. , Francisco J. , Burihan E.
Published: September 2024

The initial treatment of uncontrolled hemorrhagic shock from an abdominal source is controversial. The hemodynamic effects of transfemoral diaphragmatic aortic occlusion with a balloon followed by a single bolus of hypertonic saline solutions have been evaluated in 28 dogs. The animals were submitted to pressure-driven hemorrhage for 90 min, according to mean arterial pressure in the abdominal aorta and randomized into four groups, according to the treatment employed at 34 min after hemorrhage. Group 1 dogs (controls) received isotonic NaCl (0.9%, 308 mOsm/l, 4 ml/kg) without aortic occlusion; group 2 underwent aortic occlusion and received isotonic NaCl (0.9%, 308 mOsm/l, 4 ml/kg); group 3 were occluded and received hypertonic NaCl (7.5%, 2400 mOsm/l, 4 ml/kg); group 4 were occluded and received hypertonic sodium acetate (10.5%, 2400 mOsm/l, 4 ml/kg). There were no significant differences between groups at basal measures and also after 30 min of continuous bleeding, when animals presented with severe shock, and significant decreases in mean arterial pressure, cardiac index, systolic index and cardiac filling pressures; the systemic vascular resistance index was increased. Control animals remained in severe shock throughout the experiment and three died. The recovery of mean arterial pressure in aortic-occluded dogs given isotonic NaCl was associated with a marked increase in systemic vascular resistance index, without improvements in cardiac index, systolic index and cardiac filling pressures. In occluded dogs given hypertonic NaCl and NaAc the mean arterial pressure recovery lasted longer, with lower increases in systemic vascular resistance index, while the cardiac index, systolic index and cardiac filling pressures showed a marked albeit transient increase. Injection of hypertonic saline following aortic occlusion produced significantly better hemodynamic profiles and should be seriously considered for the first treatment in severe uncontrolled hemorrhagic shock from an abdominal vascular source.
Intravenous Leiomyomatosis with Intracardiac Extension
Authors: Ricci M. A. , Cloutier L. M. , Mount S. , Welander C. , Leavitt B. J.
Published: September 2024

Intravenous leiomyomatosis is a benign smooth muscle tumor of uterine origin characterized by grossly visible masses of smooth muscle cells growing within venous channels. A case of leiomyomatosis arising in the uterine veins with extension into the right iliac veins, vena cava, right atrium, right ventricle and into the pulmonary outflow tract is described. The tumor was completely and successfully removed by a staged approach with median sternotomy followed by laparotomy several days later. A brief review of the literature and a discussion of the operative approach are presented.
Contained Rupture of Infected Abdominal Aortic Aneurysm due to Systemic Candidiasis
Authors: Ikeda M. , Kambayashi J. , Kawasaki T.
Published: September 2024

A case is reported of contained rupture of an infected abdominal aortic aneurysm as a result of vascular catheter-associated candidiasis. Candida was identified in the mural thrombus taken from the aneurysm during surgery. Since Candida has played an important role in nosocomial infection and catheter-associated sepsis during the past decade, it is becoming an increasingly significant pathogen in microbial arteritis. Successful treatment included axillobifemoral bypass grafting followed by a complete excision of the infected aneurysm, retroperitoneal drainage and long-term antifungal therapy. Although infected abdominal aortic aneurysm is not common, without surgical intervention it may lead to serious consequences, such as rupture or uncontrollable sepsis. As the clinical symptoms of this disease are minimal and non-specific during the early stages, a high index of suspicion for this condition is essential for precise diagnosis and successful treatment. Moreover, initial treatment of candidiasis is especially important to prevent this rare but fatal late complication, infected abdominal aortic aneurysm.
Durability of Emergency Coronary Artery Bypass for Complications of Failed Angioplasty
Authors: Ladowski J. S. , Dillon T. A. , Deschner W. P. , DeRiso A. J. , Peterson A. C. , Schatzlein M. H.
Published: September 2024

Although emergency coronary artery bypass for complications of percutaneous transluminal coronary angioplasty (PTCA) has proved to be a relatively successful ‘bail-out’ procedure, little is known about the durability of revascularization under these potentially disastrous circumstances. The authors therefore retrospectively examined their results with this procedure. Emergency coronary artery bypass for complications of PTCA was performed in 112 patients between 1 January 1984 and 19 May 1992. Fifteen patients underwent PTCA for acute myocardial infarction. Eleven patients (9.8%) were stable, and underwent emergency coronary artery bypass after PTCA because of suboptimal angiographic results from percutaneous transluminal coronary angioplasty. None of these stable patients died. The remainder of the patients underwent emergency coronary artery bypass after PTCA because of ongoing documented ischemia, including cardiac arrest requiring cardiopulmonary resuscitation during transit to the operating room in 11 patients (9.8%) and preoperative intra-aortic counterpulsation in 24 (21.4%). The average number of coronary arteries bypassed at emergency coronary artery bypass was 2.2, and 19 patients (17%) received at least one mammary artery conduit. The perioperative incidence of myocardial infarction was 8.9% (10/112), and the operative mortality rate 8% (9/112). During follow-up, which averaged 55 months, the survival rate (Including operative mortality) was 85% while 98% of patients experienced freedom from reoperative coronary bypass, 89% experienced freedom from myocardial infarction (including postoperative) and 90% experienced freedom from subsequent catheterization or PTCA. In conclusion, emergency coronary artery bypass for PTCA complications successfully avoids subsequent untoward cardiac events. When compared with published results of PTCA without emergency coronary artery bypass, emergency coronary bypass is more reliable for avoiding subsequent cardiac catheterization (with or without PTCA) than PTCA alone.
Natural History of Allograft Coronary Arteriopathy: A Retrospective Study of 54 Patients over a 81/2-Year Period
Authors: Park S. J. , Pifarre R. , Sullivan H. , Montoya A. , Kim S. Y.
Published: September 2024

A total of 288 patients underwent heart transplantation at Loyola University Medical Center over a 81/2-year period starting in March, 1984. Of these patients. 54 were identified as having allograft coronary arteriopathy. Diagnosis was made on the basis of abnormal findings on coronary angiography in 44 patients; either an autopsy or explanted heart revealed the diagnosis in the remainder. A total of 279 abnormal lesions were identified by coronary angiography, and over 70% of these stenoses were discrete and located in large epicardial vessels. The left ventricular ed-diastolic pressure demonstrated a steady rise over time (2.5 mmHg/year), and also correlated with the degree of allograft coronary arteriopathy stenosis. The rate of stenosis progression was 33% per year from the time of initial allograft coronary arteriopathy development. Actuarial survival rate was lower than that of patients with arteriopathy. In conclusion, first, the majority of allograft coronary arteriopathy stenoses detected on coronary angiography are discrete, involve large epicardial vessels, and progress rapidly over time. Second, left ventricular end-diastolic pressure seems to reflect the degree of allograft coronary arteriopathy stenosis, and may prove to be a useful indicator of left ventricular dysfunction related to allograft coronary arteriopathy. Third, patients with allograft coronary arteriopathy show a decreased actuarial survival rate.
Blood Cyst with a Calcium Stone Originating from the Right Atrial Septum
Authors: Niinami H. , Ishihara S. , Hara S. , Tanaka S. , Yamaguti E. , Takase S.
Published: September 2024

Blood cysts of the heart in adults are extremely rare, and their origin is usually from the valvular apparatus. However, a case was encountered of a blood cyst originating from the right atrial septum of a 59-year-old woman. Furthermore the cyst contained calcium stone. The cyst with the stone was successfully excised. Neither situation has been reported previously in the literature.
Coeliac Artery Aneurysm: A Case Report
Authors: Gupta R. , Khanna S. K. , Chaudhary A. , Tyagi S. , Tempe D. K.
Published: September 2024

Coeliac artery aneurysms are rare. A case of coeliac artery aneurysm treated successfully by endoaneurysmorrhaphy is presented. Although excision with arterial reconstruction is usually recommended, endoaneurysmorrhaphy can also be considered in selected cases.
Conservative Surgery for Aortic Graft Infection
Authors: Earnshaw J. J.
Published: September 2024

Surgery for aortic graft infection is a major challenge often characterized by the need for ingenuity and improvisation. Traditional treatment is by total graft excision and extra-anatomic bypass. In situ replacement of the infected graft using either autogenous tissue or antibiotic-impregnated Dacron is effective in selected cases but it is not clear when such conservative treatment may be employed. Graft excision and thorough débridement of infected tissue are important, whichever technique is used. It would seem unwise to perform in situ reconstruction unless the remaining operative field is free from contamination. When in situ replacement is selected, a rifampicin-soaked Dacron graft is the easy option, but large studies will be needed to determine whether this is a suitable long-term alternative to conventional treatment.
Survival and Aortic Events after Graft Replacement for Thoracoabdominal Aortic Aneurysm
Authors: Schepens M. A. A. M. , Dekker E. , Hamerlijnck R. P. H. M. , Vermeulen F. E. E.
Published: September 2024

Graft replacement remains the procedure of choice for patients with thoracoabdominal aortic aneurysm. Since there is little information regarding the long-term survival following these major vascular operations which may carry a risk of various late complications, a retrospective analysis of 10 years follow-up was undertaken. The results of 172 consecutive operations for thoracoabdominal aortic aneurysm were analysed retrospectively. Hospital mortality rate was 10.5%. Temporary postoperative haemodialysis was necessary in 10.4% of cases and paraplegia occurred in 8.2%. The mean (s.e.) overall cumulative 2-, 5- and 10-year observed survival rate was 76(3.4), 53(4.5) and 19(7)%, respectively while expected survival of a background population at 2, 5 and 10 years was 94%, 85% and 71%, respectively. Reoperation for an early (<7 days) or late (>7 days) aortic event was necessary in 31 patients. If performed electively, the hospital mortality rate for late aortic reoperation was only 7% but at emergency reoperation, hospital mortality rate was 100%.
Polytetrafluoroethylene Grafts for Carotid Repair
Authors: Becquemin J. P. , Cavillon A. , Brunei M. , Desgranges P. , Melliere D.
Published: September 2024

Polytetrafluoroethylene grafts are well established for bypassing occlusive disease in the lower limb but there are few reports which deal with the long-term results of such grafts in the neck. The present study was undertaken to evaluate the immediate and long-term results of polytetrafluoroethylene grafts for carotid repair. Between 1982 and 1991, 591 carotid operations (mostly endarterectomies) were performed by the authors. In 32 cases a polytetrafluoroethylene graft was used to replace ( n = 12) or to bypass ( n = 20) a stenotic lesion of the internal carotid artery. Postoperative angiography was obtained in all patients and the follow-up extended from 1 month to 9 years (mean 30 months) with clinical and duplex scan surveillance. There were no deaths within the first postoperative month. There was one acute postoperative stroke (3%) caused by plaque dislodgement and one symptomless occlusion demonstrated by routine angiography. During follow-up, seven patients died from other causes. No patient developed new neurological symptoms but routine duplex assessment showed one symptomless graft occlusion. The cumulative survival rate was 96% at 1 year and 91% at 4 years. The cumulative primary patency rate was 93% at 1 month, 89% at 1 year and 89% at 4 years. In specific situations polytetrafluoroethylene grafting is an adequate alternative to carotid endarterectomy but is not recommended by the authors as a routine procedure because of its occlusion rate (>6.2%).
Plasma Endothelin-1 Levels in Adult Patients Undergoing Coronary Revascularization
Authors: St. Rammos K. , Koullias G. J. , Hatzibougias J. D. , Argyrakis N. P. , Panagopoulos P. G.
Published: September 2024

Cardiopulmonary bypass is thought to injure all endothelial cells, mainly by cell-to-cell interaction with activated granulocytes which, augmented by endothelin-1 (ET-1), enhance the generation of superoxide radicals. These radicals on the other hand, may sustain and prolong endothelial injury. In the present study, by means of a magnetic separation radioimmunoassay procedure, ET-1 levels were measured in 10 adult patients undergoing coronary artery bypass surgery, in 10 perioperative phases, in order to reconfirm and further elucidate the effect of cardiopulmonary bypass on endothelial secretion of ET-1. ET-1 levels before cardiopulmonary bypass showed a definite rising trend, especially after median sternotomy. After induction of cardiopulmonary bypass, ET-1 levels increased significantly compared with preoperative values ( P < 0.01). ET-1 levels in stable angina patients during and after aortic cross-clamping were strongly and positively correlated with preoperative mean pulmonary artery pressure ( r = 0.79, n = 7, P < 0.05 and r = 0.92, n = 7, P = 0.05) respectively. After the first hour in the intensive care unit, ET-1 levels in three patients with unstable angina were considerably higher than in those with stable angina, a fact that deserves further consideration and study.
Reduced Blood Flow Accelerates Intimal Hyperplasia in Endarterectomized Canine Arteries
Authors: Chen C. , Coyle K. A. , Hughes J. D. , Lumsden A. B. , Ku D. N.
Published: September 2024

The purpose of this study was to evaluate a technique that accelerates intimal hyperplasia by reduction of blood flow. Bilateral endarterectomies were performed in both femoral and carotid arteries in six dogs. One week later, all animals underwent banding of an artery distal to the injured region to reduce the blood flow by 50%. The contralateral injured arteries served as controls. At 11 weeks, the specimens were harvested and analyzed. Five of 12 (42%) of the flow-restricted arteries and nine of 12 (75%) of the non-flow-restricted arteries were patent at 11 weeks ( P<0.05). Marked stenotic intimal hyperplastic lesions developed in the flow-restricted arteries (69% stenosis) as compared with the non-flow-restricted arteries (37% stenosis). Mean(s.d.) intimal thickness, intimal areas, and intimal/medial area ratio were 0.52(0.19) mm, 3.17(1.11) mm2, and 1.12(0.33)%, respectively, in the flow-restricted arteries. Their counterparts in the non-flow-restricted arteries were 0.21(0.09) mm, 1.70(1.09) mm2, and 0.58(0.14)%, respectively ( P<0.05). Extracellular matrix comprised 48% of total intimal volumes in the flow-restricted arteries. Cell proliferation and occluded arteries were also characterized. These data demonstrate that reduction of blood flow significantly accelerated intimal hyperplasia and occlusion rates in endarterectomized arteries. Advanced intimal hyperplastic lesions (>50% stenosis) possess a high extracellular matrix content. This new animal model is a reliable generator of advanced stenotic lesions in a relatively short time period and can be used to study biologic mechanisms of stenosis and evaluate therapeutic interventions.
Aortic Allograft and Pulmonary Autograft for Aortic Valve Replacement: Mid-Term Results
Authors: Rubay J. E. , Sluysmans T. , Vanoverschelde J. L. , Buche M. , El Khoury G. , Dion R. , Schoevaerdts J. C.
Published: September 2024

Between April 1990 and August 1996, 138 patients (median age 42 years, range 10 days to 66 years) underwent aortic valve or root replacement with allografts ( n = 70) or autografts ( n = 68). Aortic stenosis was the main indication (80 patients, 58%) followed by aortic incompetence (31 patients, 22%). Twenty-five patients had endocarditis (18%) and two patients had truncus repair (2%). Some 140 allograft valves were inserted (70 pulmonary. 70 aortic). Most of the valves were conditioned and cryopreserved by the European Homograft Bank, Brussels, Belgium. Subcoronary implantation was performed in 46 patients, intraluminal cylinder in 29 and root replacement in 63. Peroperative transoesophageal echocardiography was routinely used. Three patients required valves replacement by mechanical valves at the time of surgery due to technical failure. Seven patients (5%) died early, while 131 were followed up from 1 to 76 months (mean 32 months). There were two late deaths. All survivors are in NYHA class I and currently free of any medication. There have been no thromboembolic events. Three patients developed endocarditis (2%). Transthoracic echocardiography was performed routinely in all patients; an initial study showed grade 1 aortic incompetence in nine patients and grade 2 in two. Late studies up to 6 years after surgery showed progression of aortic incompetence in 18 of 43 survivors with subcoronary implantation and in four of 75 survivors who underwent other techniques ( P < 0.002). In congenital patients with preoperative aortic incompetence, the left ventricular function has been prospectively analysed by echocardiography. Risk factors have been identified as dilated ventricles with spherical shapes, thin wall and reduced velocities by measuring ejection fraction and velocity of shortening of myocardial fibres. Allograft and autograft replacement of the aortic valve can be performed with excellent results. Considering the risk of degeneration of allografts, and the growth potential of the pulmonary autograft, this should be regarded as the optimal method of treatment for diseased aortic valves in neonates, children and young adults.
Combined Carotid and Coronary Artery Surgery: What Have We Learned after 15 Years?
Authors: Perić M. , Huskić R. , Nežić D. , Gradinac S. , Popović Z. , Popović A. D. , Bojić M.
Published: September 2024

Optimal surgical strategy in patients with concomitant coronary and carotid artery disease is debatable. We have analysed 15-years of experience (January 1981-August 1996) with 195 consecutive patients in whom we have used two different surgical approaches. Group A consisted of 48 patients who underwent a single-stage surgical procedure, and group B (147 patents) underwent a two-stage procedure, either as carotid endarterectomy followed by coronary artery bypass surgery (group B1, 97 patients), or as coronary artery bypass surgery followed by carotid endarterectomy (group B2, 50 patients). Overall, there were 40 (20.5%) patients with left main coronary artery disease, 49 (25.1%) with poor left ventricular function, 128 (65.6%) with previous myocardial infarction, 134 (68.7%) were in New York Health Authority (NYHA) functional class III or IV, and bilateral carotid involvement was present in 57 patients (29.2%). Unstable angina was more frequent in groups A and B2 ( P < 0.0001), NYHA class III-IV was more frequent in group A ( versus B1, P = 0.001 and versus B2, P = 0.02), low ejection fraction (EF) was more frequent in groups A and B2 ( P < 0.0001 for both), bilateral carotid stenosis in groups A and B1 ( P = 0.02 and P = 0.0001, respectively) and ulcerated plaque in group B1 ( versus A, P = 0.0001). These differences dictated the surgical strategy, which resulted in different protocols for clinical and operative management.

Results:

Early mortality for the entire group was 4.6% (9/195–6.2% in group A, 6.2% in group B1 and 0% in group B2, respectively P > 0.05). Serious morbidity occurred in 7.3% of patients (14/195–8.3% in group A. 7.2% in group B1 and 6% in group B, respectively P > 0.05). Univariate analysis revealed only bilateral carotid stenosis as a predictor of outcome ( P = 0.04). Follow-up was completed for 156 patients (80.0%) and averaged 84.1 ± 13.3 months (range 1–180 months). Kaplan–Meier survival estimate for the entire group was 81% and event-free survival was 76% at 5 years. Actuarial and event-free survivals were similar for all groups. Early and late outcome in these patients were influenced more by their preoperative clinical status than by the surgical strategy itself. It is therefore concluded that surgical approach should be individualized for the majority of patients.
Premature Peripheral Vascular Disease: Clinical Profile and Abnormal Lipid Peroxidation
Authors: Harris L. M. , Armstrong D. , Browne R. , Aljada A. , Peer R. , Upson J. , Pillai L. , Curl G. R. , Ricotta J. J.
Published: September 2024

The aim of this study was to determine any biochemical differences between early-onset peripheral vascular disease and typical onset atherosclerosis, and age-matched controls. A subset of patients present at a young age (< 50 years) with peripheral vascular disease which pursues an aggressive course. As lipid oxidation seems important in atherosclerosis, total lipid peroxides, oxidized subfractions, and Trolox equivalent antioxidant capacity (TEAC) were studied in patients with premature peripheral vascular disease. Charts were reviewed of patients operated on for vascular occlusive disease over a 5-year period. Patients with early-onset peripheral vascular disease (group I) were evaluated for biochemical abnormalities and compared with typical onset atherosclerotics (group II) and age-matched controls (group III). Sixteen patients with early-onset peripheral vascular disease underwent biochemical evaluation. Conventional lipid profiles did not differ statistically from those of age-matched controls, except for mild elevations in LDL and VLDL in patients with vascular occlusive disease (207 and 195 mg/dl in groups I and II versus 157 mg/dl in group III). Total oxidative potential was significantly elevated ( P = 0.006) 3.04, 2.15 and 2.04 nmol/ml in groups I, II and III, respectively. Levels of oxidized LDL and VLDL were even more significantly elevated ( P = 0.0009) for premature peripheral vascular disease, (1.2, 0.58 and 0.47 nmol/ml in groups I-III). TEAC values did not differ significantly between groups (0.83, 0.82, 0.82 nmol/ml) and did not correlate with total lipid peroxide values for individual patients. In conclusion, lipid peroxides were significantly elevated in patients with premature peripheral vascular disease, the most marked changes being seen in oxidized LDL and VLDL subfractions. Lipid peroxides were elevated when standard lipid profiles were only mildly abnormal. The poor long-term prognosis in these patients suggests the need for aggressive evaluation and treatment of lipid abnormalities.
Miniaturized Implantable Rotary Blood Pump in Atrial-Aortic Position Supports and Unloads the Failing Heart
Authors: Meyns B. , Siess T. , Nishimura Y. , Racz R. , Reul H. , Rau G. , Leunens V. , Flameng W.
Published: September 2024

The purpose of this study was to test the pump performance of a miniaturized, newly developed, implantable rotary blood pump (the diagonal pump). In a series of six sheep, the pump was interposed in an atrial-aortic connection. Heart failure was induced by serial injection of glass beads into the left coronary artery. The assistance of the non-failing heart (with pump output up to 4.5 liter/min) did not change the total cardiac output or the blood pressure of the animal. The heart was significantly unloaded as demonstrated by a drop in first derivative of the left ventricular pressure (dP/dt) max (from 1645 to 1113 mmHg/s; P = 0.0003). Because of the specific interaction between heart function and rotary blood pump performance, the pump provided considerably more flow in the failing than in the non-failing heart. Cardiac output and perfusion pressures were restored to pre-assist values in the failing heart model. The heart-rotary blood pump interaction is an ideal substrate for long-term assistance. With this miniaturized rotary blood pump, hemodynamics in a severely failing heart can be restored. Atrial cannulation, which leaves the left ventricle untouched, provides similar results as apical cannulation in the failing heart.
Thoracic Aortic Aneurysm Associated with Congenital Bicuspid Aortic Valve
Authors: Ando M. , Okita Y. , Morota T. , Takamoto S.
Published: September 2024

Congenital bicuspid aortic valve is a relatively rare malformation. It is reported that the presence of this anomaly predisposes the patient to development of true aortic aneurysms or dissecting aortic aneurysms. Between 1981 and August 1997, 25 patients with an aneurysm of the thoracic aorta associated with congenital bicuspid aortic valve underwent surgical treatment at the authors' institution. There were 20 males and five females. The age of the patients ranged from 27 to 74 years (mean 53 years). There were 18 patients with true ascending aortic aneurysms (of which 10 presented with annulo-aortic ectasia) and seven with dissecting aortic aneurysms (four with DeBakey type I dissection, two with type II and one with type IIIb). These 25 patients constituted 2.6% (25/973) of all cases of surgical operations for aneurysms in the thoracic aorta. Aortic valve dysfunction was noted in 20 patients. The authors performed a valved conduit operation in nine patients, aortic valve replacement and wrapping of the ascending aorta in six, graft replacement of the ascending aorta in five, graft replacement of the ascending aorta and aortic arch in four, and graft replacement of the descending aorta in one. No hospital deaths occurred in the authors' patients. Pathological examination of surgical specimens of the aortic wall showed cystic medial necrosis in 11 patients and mucoid degeneration in nine. In patients with congenital bicuspid aortic valve, attention should be paid to aneurysmal dilatation and aortic dissection as complications in addition to valve dysfunction.
How I do it: Thoracoabdominal Aortic Aneurysm Graft Replacement
Authors: Safi H. J.
Published: September 2024

A technique of aortic graft replacement in thoracoabdominal aortic aneurysm repair is described. The author's experience with the surgical adjuncts of cerebrospinal fluid drainage and distal aortic perfusion, and the evolution and rationale of thoracoabdominal aortic aneurysm classification are discussed. Interpretation of the large amount of data that the author has accumulated would have been impossible without such a system.
Predictors for COVID-19-Specific and Non-COVID-19-Specific Deaths: A Cohort Study in Taiwan
Authors: Chan Shang-Yih , Lai Hsin-Hao , Lai Yun-Ju , Huang Chao-Ming , Chen Chu-Chieh , Chang Shen-Shong , Yen Yung-Feng , Chiu Yi-Chun
Published: September 2024

Predictors for coronavirus disease 2019 (COVID-19)-specific and non-COVID-19-specific deaths have not been extensively studied. This cohort study in Taiwan investigated predictors for COVID-19-specific and non-COVID-19-specific deaths among hospitalized patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. From January to July 2022, 2196 COVID-19 patients at Taipei City Hospital were consecutively recruited in this cohort study. Among the 175 deceased COVID-19 patients, 147 (84.0%) and 28 (16.0%) had COVID-19-specific and non-COVID-19-specific deaths, respectively. After controlling for other covariates, multinomial logistic regressions showed that age ≥ 65 was significantly associated with higher risks for both COVID-19-specific, adjusted odds ratio (AOR) = 6.21; and non-COVID-19-specific deaths (AOR = 6.06). Fully vaccinated individuals (AOR = 0.50) and Paxlovid recipients (AOR = 0.45) had lower COVID-19-specific death risks, while comorbid cancer or end-stage renal disease patients faced higher risks of non-COVID-19-specific deaths. Our study findings suggest that vaccination and Paxlovid treatment are crucial for reducing SARS-CoV-2-specific mortalities, while comorbid patients need careful monitoring to reduce non-COVID-19-specific deaths.
How Vertical Leadership Affects Shared Leadership Through Team Identification
Authors: Schummer Steffen Erik , Woelk Jona , Trupp Lisa , Otto Kathleen
Published: September 2024

Shared forms of leadership have become increasingly important for organizational success. While research has emphasized that a single leader’s engagement in specific leadership behaviors (vertical leadership) can foster team members’ engagement in shared leadership behaviors, knowledge on the mediating processes is limited. Drawing on social identity theory, we argue that a single leader’s engagement in transformational leadership fosters team members’ identification with their team, which leads to team members’ engagement in shared transformational leadership and shared contingent reward. To test this, we collected data from 698 team members in 92 teams in a German financial services company. Team identification was found to be positively related to shared transformational leadership and shared contingent reward, and mediated the relationships between vertical transformational leadership and shared transformational leadership and shared contingent reward. Our findings underline the importance of team members’ identification processes for the interrelations of vertical and shared leadership.
A review of multiaxial low-cycle fatigue criteria for life prediction of metals
Authors: Pagliari Lorenzo , Concli Franco
Published: September 2024

Most of real-world structural components that undergo cyclic loading feature multiaxial fatigue. When the cyclic loading involves also significant plastic deformation, multiaxial low-cycle fatigue takes place. Applications where multiaxial low-cycle fatigue can be observed very often involve metal components. To predict their lives multiple criteria and models have been proposed, but their development has not followed a regular path. Multiple reviews are available in literature. However, many of them are outdated, they often employ different classification methods to categorize available criteria, many focus on specific families of criteria, and others do not include sufficient theoretical background. Moreover, none of the available reviews is based on a systematic literature search method. As a result, approaching the topic can result arduous and chaotic, especially for first timers. This work aims at providing a clear, comprehensive, and definitive review of available criteria for multiaxial low-cycle fatigue. First, the basic theoretical background is explained. Secondly, a systematic approach is described and employed to identify all major currently available criteria. Then, they are classified and commentary about different classification styles that can be found in literature is added. Eventually they are described, together with their latest proposed variations. In this way this review can be employed as a guiding reference, especially for engineers approaching the topic for the first time.
A peridynamic formulation for planar arbitrarily curved beams with Timoshenko–Ehrenfest beam model
Authors: Vo Duy , Ditcharoen Watthanaphongpun , Aung Zwe Yan , Suttakul Pana , Atroshchenko Elena , Rungamornrat Jaroon
Published: September 2024

In this study, a peridynamic formulation is proposed for analysis of planar arbitrarily curved beams. Assumptions of Timoshenko–Ehrenfest beam model are considered such that linear kinematic relations are described by displacements of the beam axis and rotation of the cross-section. Equilibrium conditions and boundary conditions are derived by means of the principle of virtual work. Then, peridynamic functions are constructed, and incorporated with equilibrium conditions to develop a peridynamic formulation. Several examples are exhibited to examine the performance of the proposed formulation in some regards, i.e., numerical accuracy, convergence properties, and locking effects. It is delineated that the proposed formulation provides a good level of precision for the analysis of relatively thick beams. However, membrane and shear locking effects are present in the analysis of slender beams, and peridynamic functions of higher polynomial degree can be used to mitigate these unfavorable effects.
Evolutionary Perspective on Tourists’ Conformity to the Minority: The Effect of Mating Motive
Authors: Wang Mengfei , Qiu Shangzhi (Charles) , Fang Yizhi
Published: September 2024

Tourists tend to conform to the majority when faced with uncertainty in decision-making, which poses a considerable challenge to the promotion of new, less popular tourism offerings. This study delves into the heuristic promotion of less popular tourism offerings by using the concept of mating motives from the field of evolutionary psychology. Findings show that tourists driven by mating motives are likely to follow the minority, rather than the majority, when making purchase decisions—particularly in the context of souvenir shopping, destination selection, and gift giving—with uniqueness seeking playing a mediating role. Although purchase risk can increase the tendency of tourists to conform to the majority, it does not mitigate the effect of mating motives. The findings contribute to the promotion of less popular tourism offerings by highlighting tourists’ uniqueness seeking. This study broadens knowledge on tourist conformity behavior from the theoretical perspective of evolutionary psychology.
Cost Analysis of Outpatient Colectomy in a Tertiary Center: A Projected Medico-Economic Evaluation
Authors: Agri Fabio , Möller William , Deslarzes Philip , Vogel Charles André , Hahnloser Dieter , Hubner Martin , Demartines Nicolas , Grass Fabian
Published: September 2024

Aim of the study:

Short stay processes are incentives to unburden chronically stressed healthcare systems. The aim of this study is to analyze financial implications of day admission (DAS) and outpatient strategies for colon resections in a prospective payment system (PPS) using Diagnosis Related Group (DRG) coding.

Methods:

Consecutive patients undergoing left and right colonic resections between January 1, 2019 and December 31, 2020 were included. Medico-economic evaluations of the virtual outpatient and day admission surgery groups based on predefined criteria were compared to the identical group of patients who underwent surgery in the actual traditional inpatient setting. In a second step, postoperative complications of the virtual outpatient group were assessed. Cost-revenue analysis was performed using a micro-costing approach including direct medical costs.

Results:

Overall (N = 257), 97 (37.7%) colectomies would have been potentially eligible for an outpatient strategy. The global costs of the actual inpatient strategy totaled USD 3 634 392 with a global revenue of USD 3 571 069, corresponding to a cost coverage rate of 98%. The result of the virtual DAS strategy would have been a net loss of USD 15 800 (coverage rate of 99%) due to 4 low length of stay outliers triggering a reimbursement reduction and preventing a positive net result of USD 16 208. The pilot reference outpatient case’s revenue and cost amounted to respectively USD 7479 and USD 6911 (cost coverage of 108%).

Conclusion:

From both any given hospital and healthcare system point of view, elective outpatient colectomy for selected patients is the most cost-saving option. However, in a prospective payment system implemented to avoid bad incentives, the latter can unintentionally disadvantage best performing hospitals and impede widespread adoption of high-value strategies.