[Superior vena cava thrombosis or stricture secondary to implanted central venous access: Six cases of endovascular and direct surgical treatment in cancer patients]

Superior vena cava (SVC) stenosis or thrombosis is a well-known complication of central venous catheterization for endocavitary treatments, hemodialysis, or chemotherapy. In cancer patients, these SVC lesions are often symptomatic due to intimal damage and chemotherapy toxicity. We report our experience with six patients treated between 2007 and 2012 via an endovascular approach (n=5) or a direct surgical approach (n=1). All patients had SVC syndrome with facial edema, headache and upper limb edema. In three cases, the catheter was in place when the clinical symptoms occurred. Duplex Doppler and computed tomography (CT)-angiography identified the following lesions: isolated SVC stenosis (n=2); SVC stenosis with right Pirogoff confluence stenosis (n=1); SVC stenosis associated with left innominate vein thrombosis and right Pirogoff confluence stenosis (n=1); SVC thrombosis affecting azygos flow (n=2). In one patient, the thrombus extended into the right atrium. Five patients underwent endovascular repair via a right jugular approach (n=2) or a double jugular approach (n=3). Treatment involved: SVC angioplasty with stent (n=2); right Pirogoff angioplasty and SVC stent (n=1); kissing angioplasty of both innominate trunks with a SVC stent (n=1); and SVC angioplasty without stent because of an incomplete result with a residual lumen less than 8mm (n=1). One patient had a complete SVC occlusion with extension of thrombus into the right atrium. She was treated via a median sternotomy for open surgical control of both innominate trunks and lateral clamping of the right atrium. A long cavotomy prolonged on the right atrium allowed thrombo-intimectomy and pericardial patch angioplasty. Postoperative follow-up was uneventful in five cases. However, postoperative hemorrhage required pericardial drainage in one patient. The CT scan showed a good morphological aspect in five patients and an incomplete result in one case. Patients have been followed up annually with a duplex scan from two to six years. One patient had a restenosis at 7 months treated by a new angioplasty via a femoral approach. A new catheter was positioned via a cervical approach. Two patients died of metastatic diffusion at 8 and 32 months. The other four patients have remained asymptomatic, with a satisfactory duplex scan. In conclusion, VCS lesions after implanted central access for chemotherapy can often be treated endovascularly. Conventional surgery still has indications when lesions extend into the right atrium.

Endovascular repair of acute uncomplicated aortic type B dissection promotes aortic remodelling: 1 year results of the ADSORB trial

OBJECTIVES

Uncomplicated acute type B aortic dissection (AD) treated conservatively has a 10% 30-day mortality and up to 25% need intervention within 4 years. In complicated AD, stent grafts have been encouraging. The aim of the present prospective randomised trial was to compare best medical treatment (BMT) with BMT and Gore TAG stent graft in patients with uncomplicated AD. The primary endpoint was a combination of incomplete/no false lumen thrombosis, aortic dilatation, or aortic rupture at 1 year.

METHODS

The AD history had to be less than 14 days, and exclusion criteria were rupture, impending rupture, malperfusion. Of the 61 patients randomised, 80% were DeBakey type IIIB.

RESULTS

Thirty-one patients were randomised to the BMT group and 30 to the BMT+TAG group. Mean age was 63 years for both groups. The left subclavian artery was completely covered in 47% and in part in 17% of the cases. During the first 30 days, no deaths occurred in either group, but there were three crossovers from the BMT to the BMT+TAG group, all due to progression of disease within 1 week. There were two withdrawals from the BMT+TAG group. At the 1-year follow up there had been another two failures in the BMT group: one malperfusion and one aneurysm formation (p = .056 for all). One death occurred in the BMT+TAG group. For the overall endpoint BMT+TAG was significantly different from BMT only (p < .001). Incomplete false lumen thrombosis, was found in 13 (43%) of the TAG+BMT group and 30 (97%) of the BMT group (p < .001). The false lumen reduced in size in the BMT+TAG group (p < .001) whereas in the BMT group it increased. The true lumen increased in the BMT+TAG (p < .001) whereas in the BMT group it remained unchanged. The overall transverse diameter was the same at the beginning and after 1 year in the BMT group (42.1 mm), but in the BMT+TAG it decreased (38.8 mm; p = .062).

CONCLUSIONS

Uncomplicated AD can be safely treated with the Gore TAG device. Remodelling with thrombosis of the false lumen and reduction of its diameter is induced by the stent graft, but long term results are needed.

[Massive hemoptysis following thoracic aortic rupture: an advancing field]

We report the case of a 57-year-old woman who presented with massive hemoptysis and thoracic pain 3 years after the endovascular treatment of a thoracic aortic aneurysm. Emergency work up revealed the presence of an endoleak, leading to the pressurization of the aneurysm sac and its subsequent rupture into the lung parenchyma. The discussion includes presentation, clinical course, diagnosis, complications and new therapeutic options in the management of a massive hemoptysis secondary to aortic rupture. All together, the case and discussion highlight the classical rules of critical care and the recent advances in endovascular treatment of thoracic aortic rupture.

[Pediatric lung transplantation in Broussais-HEGP: a 23-year experience (1990-2013)]

INTRODUCTION

Pediatric lung transplantations (LTx) remains a small part of LTx performed worldwide. The majority of these Tx concerns young adolescents, transplantations in infants being anecdotic. We conducted a retrospective study of LTx in children and adolescents in one center in Paris from the beginning of the 90's to 2013.

METHODS

Data from Broussais then HEGP were collected retrospectively from 1990 to 2013: 380 LTx were reported in 368 patients including 111 LTx performed among children from 5 to 18 years of age (30%).

RESULTS

One hundred and eleven patients received 121 LTx: 86 bilateral LTx, 13 combined lung-liver, 3 monopulmonary, 5 heart-lung and 4 combined heart-lung-liver Tx. Eighty-eight percent of the patients had cystic fibrosis. Median age was 14 years, weight 34 kg and height 144 cm. Median age of donors was 27 years, weight 60 kg and height 167 cm. Conditional survival for children was not different than adults: 72% at one year, 42% at 5 years, 37% at 10 years and 26% at 15 years. There was not overall early mortality after transplantation. Era graft survival was significantly higher after year 2000 (53% at 5 years vs 32% P=0.03).

CONCLUSION

Lung transplantation among children under 18 years have similar outcome to those of adult patients.

Very late heart transplant rejection is associated with microvascular injury, complement deposition and progression to cardiac allograft vasculopathy

In heart transplants, the significance of very late rejection (after 7 years post-transplant, VLR) detected by routine endomyocardial biopsies (EMB) remains uncertain. Here, we assessed the prevalence, histopathological and immunological phenotype, and outcome of VLR in clinically stable patients. Between 1985 and 2009, 10 662 protocol EMB were performed at our institution in 398 consecutive heart transplants recipients. Among the 196 patients with >7-year follow-up, 20 (10.2%) presented subclinical ≥3A/2R-ISHLT rejection. The VLR group was compared to a matched control group of patients without rejection. All biopsies were stained for C4d/C3d/CD68 with sera screened for the presence of donor-specific antibodies (DSAs). In addition to cellular infiltrates with myocyte damage, 60% of VLR patients had evidence of intravascular macrophages. C4d and/or C3d-capillary deposition was found in 55% VLR EMB. All cases of VLR associated with microcirculation injury had DSAs (mean DSA(max) -MFI = 1751 ± 583). This entity was absent from the control group (p < 0.0001). Finally, after a similar follow-up postreference EMB of 6.4 ± 1 years, the mean of CAV grade was 0.76 ± 0.18 in the control group compared to 2.06 ± 0.26 in the VLR group respectively, p = 0.001). There was no difference in patient survival between study and control groups. In conclusion, VLR is frequently associated with complement-cascade activation, microvascular injury and DSA, suggesting an antibody-mediated process. VLR is associated with a dramatic progression to severe CAV in long-term follow-up.

[Stenting or coronary artery bypass surgery for triple vessel disease?]

This review was undertaken to objectively analyse the cumulated medical literature on techniques of myocardial revascularization (angioplasty, bare metal stenting, drug eluting stenting, coronary artery surgery) in multivessel coronary artery disease. Randomized trials, meta analyses and registries comparing these treatment modalities show a short and long term advantage of surgery over percutaneous techniques for angina recurrence and need for repeat revascularization, although mortality and myocardial infarction rate do not seem statistically different. Diabetes mellitus, chronic renal failure and female gender represent high risk subgroups. Data on drug eluting stents are to date limited to the short term; however, it does not seem that drug eluting stents have resolved the need for repeat revascularization. Stenting addresses focal lesion whereas future revascularization occurs on other coronary sites by progression of coronary disease. Cardiologists should objectively inform the consenting coronary multivessel disease patient on the risk of repeat revascularization inherent to percutaneous techniques and on the weight of actual data favouring surgery in multivessel disease.

[Systolic anterior motion (SAM): a rare cause of late failure in mitral valve repair]

Systolic anterior motion (SAM) of the mitral valve is a rare complication of mitral valve repair. The treatment of the large majority of cases is purely medical. Nevertheless, an early degradation may require reoperation (revision of the repair or valve replacement). The authors report two cases of post-repair SAM with a poor outcome with medical therapy which required reoperation after several years. In both cases, an excess of bivalvular tissue with respect to the size of the mitral orifice was observed. A second repair was possible (sliding valvuloplasty associated with an oval resection of the anterior leaflet) with satisfactory long-term results. The identification of the risk factors and careful analysis of the lesions in cases of SAM after mitral valve repair may lead to a repeat repair and the avoidance of mitral valve replacement.

[Five years experience with non-pulsatile flow]

Mechanical circulatory assistances now belong to the therapeutic stock in case of advanced heart failure. Their mainspring lays on the substitution of the failing left and/or right ventricle function with a pump. The goal being to maintain or restore the system main functions. Their main indication is a bridge to transplant mechanical circulatory assistance, allowing the patient to await transplantation. However, indications for definitive implantation appear in case of transplantation counter indication, mechanical circulatory assistances already emerging as a possible alternative to transplantation. For over 10 years, we have used pulsatile flow assistances, either with pneumatic ventricles or electro-mechanic implantable left ventricles. We henceforth observe the development of a new generation of implantable assistance providing a non-pulsatile flow. These are axial pumps. We evaluated the first model, the DeBakey axial pump which became the most used axial pump worldwide. We now observe the development of other axial pumps as well as the development of new implantable centrifugal pumps.

[Prevention and treatment of atrial fibrillation after cardiac surgery]

The incidence of postoperative atrial fibrillation in cardiac surgery is still high despite major advances in anesthetic, pharmacological and surgical techniques. Its precise mechanism is still totally unknown. Postoperative atrial fibrillation increases length of stay as well as hospital costs. Rate of postoperative atrial fibrillation spontaneous conversion is high. Several protocols have been developed for prevention and/or treatment of postoperative atrial fibrillation. Beta-blockers, amiodarone and atrial pacing reduce.atrial fibrillation incidence as compared to placebo. On the other hand, amiodarone and propafenone achieve a high conversion rate of installed postoperative atrial fibrillation. However, among many pharmacological options, the best treatment is still to be defined.

[Pediatric mechanical circulatory assistance. Biventricular assistance for fulminant myocarditis in a 5 year old child]

The authors report the case of a 5 years old infant with cardiogenic shock due to a fulminant myocarditis. The severity of the shock which was refractory to conventional therapies necessitated to require to a cardiopulmonary bypass on emergency, followed by an external pneumatic bi-ventricular assistance. After 10 days (3 days with cardioplumonary bypass and 7 days of bi-ventricular assistance), the patient had been able to be disconnected of any mechanical circulatory supply with total recovery of the cardiac function.

Bridge to transplantation with the DeBakey VAD axial pump: a single center report

AIMS

To report our experience with a left ventricular assist device axial pump as a bridge to transplantation: the DeBakey Ventricular Assist Device (VAD).

METHODS

From February 1999 to February 2002, nine patients (among which eight males), with a mean age of 47 years, all in NYHA functional class IV, were proposed for a bridge to transplantation with the DeBakey VAD. Five patients had primary dilated cardiomyopathy, four had ischemic cardiomyopathy. All the patients had inotropic support prior to the intervention (dobutamine with a mean dose of 12 mcg/kg per min), six had an intra-aortic counterpulsation, four presented ventricular rhythm disorders. Interventions were performed through sternotomy alone (no need for an abdominal pocket) under extra-corporeal circulation on beating heart (except in one patient suffering from an apical thrombosis for which cardioplegic arrest was performed) as followed: implantation of the apical inflow cannula, tunneling of the percutaneous cable, implantation of the outflow graft under aortic side clamping, starting of the DeBakey VAD during CPB weaning-off.

RESULTS

Mean support duration was 81+/-62 days (16-224 days). Eight reoperations were required (three for bleeding or cardiac tamponade, one for haemoperitoneum, one for aortic bifurcation thrombectomy, one for right ventricular assist device implantation, two for iterative replacements of the DeBakey VAD). A significant hemolysis was observed in two patients. No device infection or dysfunction were observed. Secondary recovery of a pulsed flow was observed either clinically or by Echo-Doppler in six patients. Five patients were transplanted, four died prior to transplantation (three from multi-organ failure on post-operative day 35, 16 and 50, respectively, and the last patient was found disconnected at day 109).

CONCLUSIONS

The DeBakey VAD is at the origin of renewed interest for continuous flow assist devices. Still under evaluation, the advantages of miniaturization and facility of implantation of this new device seem to be promising.

Sudden-onset paraplegia due to thrombosis of false aneurysm: late complication after prosthetic replacement of the descending thoracic aorta

Traumatic rupture involving the isthmus of the descending thoracic aorta is a rarely treated injury in vehicular accident victims. A possible long-term complication of prosthetic replacement of the damaged aortic segment is false aneurysm. This report describes a case of sudden-onset acute paraplegia resulting from thrombosis of a false aneurysm associated with a prosthesis placed 10 years earlier for repair of traumatic rupture of the aortic isthmus.

Posterior approach for simultaneous access to the popliteal and anterior tibial arteries: applications to distal arterial bypass

Arterial surgery to salvage the lower limb tends to make use of the great saphenous vein, harvested with the subject in the supine position. If this is not possible the small saphenous vein is used, harvested with the subject in the prone position, however this requires a perioperative modification of the procedure. A bypass between the popliteal and anterior tibial arteries can be performed using either a lateral or a medial and lateral approach with the patient supine. In the event of trophic disorders of the lateral compartment of the leg, these approaches are not applicable. In such cases we propose a single posterior approach. The single posterior approach was used on 10 lower limbs from 5 cadavers in the prone position. Approach to the lower part of the popliteal artery was undertaken posteriorly between the two heads of gastrocnemius. The small saphenous vein was entirely dissected 10 cm above the lateral malleolus, the Achilles tendon and short fibular vessels were retracted medially to expose the interossous fascia, which was divided over 10 cm. Medial rotation of the limb by 30 degrees exposed the anterior tibial artery. For 3 of the lower limbs an 8 cm fibular resection was necessary, whereas on the remaining 7 medial rotation enabled excellent exposure of the anterior tibial artery. The single posterior approach to the anterior tibial artery can be applied in cases requiring distal bypass, using the small saphenous vein, between the inferior part of the popliteal artery and the anterior tibial artery.

Imbalance in the synthesis of collagen type I and collagen type III in smooth muscle cells derived from human varicose veins

Varicose veins have a thickening wall. Their smooth muscle cells are disorganized as regards proliferation and production of extracellular matrix protein. An imbalance between the synthesis of collagen type I protein (collagen I) and collagen type III protein (collagen III) could explain the lack of elasticity of varicose veins. Therefore, collagen synthesis was compared in the media and in cultured smooth muscle cells derived from human control and varicose saphenous veins. An increase in total collagen synthesis was observed in the media and in smooth muscle cells derived from varicose veins. This augmentation was due to an overproduction of collagen I in cultured cells from varicose veins consistent with an increase in the release of collagen I metabolites in the media. A concomitant decrease in collagen III was observed in cultures of smooth muscle cells from varicose veins. The increase in the synthesis of collagen I in cells from varicose veins was correlated with an overexpression of the gene since mRNAs for collagen I were augmented without change in mRNA-half-life. This augmentation in the synthesis of collagen I was reduced by the addition of exogenous collagen III in cultures from varicose veins. These findings suggest a dysregulation of the synthesis of collagen I and III in smooth muscle cells derived from varicose veins.

Forearm arteries entrapment syndrome: a rare cause of recurrent angioaccess thrombosis

Entrapment syndrome below or just above the elbow is uncommon. These rare causes of neurologic or vascular entrapment are linked to anomalous anatomical structures. No case of entrapment syndrome has been reported in patients with angioaccess for hemodialysis. We report, for the first time, forearm arteries entrapment in two patients presenting with recurrent angioaccess for hemodialysis thrombosis. Anatomical, radiologic, and surgical features of these uncommon syndromes are discussed.

Very long-term results (more than 20 years) of valve repair with carpentier's techniques in nonrheumatic mitral valve insufficiency

BACKGROUND

Mitral valve repair is considered the gold standard in surgery of degenerative mitral valve insufficiency (MVI), but the long-term results (>20 years) are unknown.

METHODS AND RESULTS

We reviewed the first 162 consecutive patients who underwent mitral valve repair between 1970 and 1984 for MVI due to nonrheumatic disease. The cause of MVI was degenerative in 146 patients (90%) and bacterial endocarditis in 16 patients (10%). MVI was isolated or, in 18 cases, associated with tricuspid insufficiency. The mean age of the 162 patients (104 men and 58 women) was 56+/-10 years (age range 22 to 77 years). New York Heart Association functional class was I, II, III, and IV in 2%, 39%, 52%, and 7% of patients, respectively. The mean cardiothoracic ratio was 0.58+/-0.07 (0.4 to 0.8), and 72 (45%) patients had atrial fibrillation. Valve analysis showed that the main mechanism of MVI was type II Carpentier's functional classification in 152 patients. The leaflet prolapse involved the posterior leaflet in 93 patients, the anterior leaflet in 28 patients, and both leaflets in 31 patients. Surgical technique included a Carpentier's ring annuloplasty in all cases, a valve resection in 126 patients, and shortening or transposition of chordae in 49 patients. During the first postoperative month, there were 3 deaths (1.9%) and 3 reoperations (2 valve replacements and 1 repeat repair [1.9%]). Six patients were lost to follow-up. The remaining 151 patients with mitral valve repair were followed during a median of 17 years (range 1 to 29 years; 2273 patient-years). The 20-year Kaplan-Meier survival rate was 48% (95% CI 40% to 57%), which is similar to the survival rate for a normal population with the same age structure. The 20-year rates were 19.3% (95% CI 11% to 27%) for cardiac death and 26% (95% CI 17% to 35%) for cardiac morbidity/mortality (including death from a cardiac cause, stroke, and reoperation). During the 20 years of follow-up, 7 patients were underwent surgery at 3, 7, 7, 8, 8, 10, or 12 years after the initial operation. Valve replacement was carried out in 5 patients, and repeat repair was carried out in 2 patients. At the end of the study, 65 patients remained alive (median follow-up 19 years). Their median age was 76 years (age range 41 to 95 years). All except 1 were in New York Heart Association functional class I/II.

CONCLUSIONS

Mitral valve repair using Carpentier's technique in patients with nonrheumatic MVI provides excellent long-term results with a mortality rate similar to that of the general population and a very low incidence of reoperation.

Long-term (29 years) results of reconstructive surgery in rheumatic mitral valve insufficiency

BACKGROUND

Results of conservative surgery are well established in degenerative mitral valve (MV) insufficiency. However, there are controversies in rheumatic disease. This study is the evaluation of one center for rheumatic MV insufficiency based on a functional approach.

METHODS AND RESULTS

From 1970 to 1994, 951 patients with rheumatic MV insufficiency were operated on with the reconstructive techniques elaborated by Alain Carpentier. Aortic valve diseases were excluded. Mean age was 25.8 years (4 to 75), and sinus rhythm was present in 63%. The functional classification used was type I, normal leaflet motion, 71 patients (7%); type II, prolapsed leaflet, 311 patients (33%); and type III, restricted leaflet motion, 345 patients (36%). The combined lesion of prolapse of the anterior leaflet and restriction of the posterior was present in 224 patients (24%). Surgical techniques used were implantation of a prosthetic ring in 95%, shortening of the chords and leaflet enlargement with autologous pericardium, and commissurotomy. Hospital mortality rate was 2%. The mean follow-up was 12 years (maximum, 29 years): 8618 patients per year. Actuarial survival was 89+/-19% at 10 years and 82+/-18% at 20 years. The rate of thromboembolic events was 0.4% patients per year (33 events), with 3 deaths. Freedom from reoperation was 82+/-19% at 10 years and 55+/-25% at 20 years. The main cause (83%) of reoperation was progressive fibrosis of the MV. The actuarial rate of reoperation was 2% patients per year and was correlated to the degree of preoperative fibrosis.

CONCLUSIONS

Conservative surgery of rheumatic MV insufficiency has a low hospital mortality rate and an acceptable rate of reoperation. The results are excellent regarding the minimal risk of thromboembolic events.

Comparison of the contractile responses of human coronary bypass grafts and monkey arteries to human urotensin-II

Human urotensin-II (hU-II) is a cyclic peptide recently cloned in humans and present in human cardiac tissue and human arteries. The effects of hU-II were studied on human coronary bypass grafts in vitro. In three out of eight human mammary arteries, and two out of three human radial arteries, hU-II caused contraction; human saphenous veins did not respond to hU-II. When it exists, the contraction slowly develops and has a low-to-moderate intensity. All radial arteries obtained from young healthy non-human primates contracted strongly to hU-II.

End-to-side anastomosis using a new sutureless vascular prosthesis

Performing a conventional vascular anastomosis during minimally invasive surgery remains a technically difficult and time-consuming task. The purpose of our study was to assess the efficacy of a new sutureless vascular prosthesis. Through a left thoracotomy, a short segment of the descending aorta was bypassed in eight sheep. Our Dacron prosthesis had a cuff at one extremity. The cuff was introduced into the artery through an arteriotomy and attached to the arterial wall with clips. Surgery was performed on the sheep again 12-15 weeks later, and the prosthesis was retrieved for macroscopic and microscopic examination. At surgery, insertion of the prosthesis was easy, fast, and safe. A 3-4 mm space between each clip was required for proper attachment. At the second surgery, all prostheses were completely patent and there were no anastomotic stenoses or aneurysms. This new sutureless vascular prosthesis was easy and safe in its placement and might prove useful for video assisted vascular aortic surgery.

A recovery model of partial cardiopulmonary bypass in the rat

This study was undertaken to develop a recovery model of cardiopulmonary bypass (CPB) in rats. Twenty male Wistar rats (475-550 g) were anaesthetized, mechanically ventilated and the femoral vessels cannulated. The extracorporeal circulation circuit comprised a roller pump, a venous reservoir and a modified Capiox 308 paediatric membrane oxygenator. Priming consisted of 20 ml of fresh homologous blood and 15 ml of colloid. Anticoagulation was achieved with heparin (500 IU/kg). Blood gas analysis, blood pressure monitoring and survival studies were performed in CPB (n=10) and Sham (n=10) rats. Partial CPB was always easily established and was conducted at a flow rate of 100 ml/kg/min for 90 min Blood gas analysis and blood pressure data did not differ between the two groups. All CPB rats survived and the 3-week follow-up period remained uneventful. The rat model of CPB was easy to perform and was associated with excellent survival. This recovery model should allow us to study the pathophysiological processes underlying post-CPB multiple organ dysfunction.

[Three-dimensional modelling of thoracic aortic aneurysm. A case report]

The anatomical forms of aneurysms are sometimes complex. Three-dimensional modelisation may be valuable in understanding the configuration and spatial orientation on one hand and also help in therapeutic decision making on the other. Two types of modelisation are reported with details of their methods and their respective values.

Morphometric study of the pulmonary trunk: implications for a new approach of the Ross procedure

A pulmonary valve autograft may be proposed to replace diseased aortic valves. The explanted pulmonary valve is replaced with a pulmonary homograft with the inherent risk of calcified degeneration. A monocusp valve using the anterior pulmonary trunk has been proposed to reconstruct the right ventricular outflow tract. The aim of this study was to determine the feasibility of this technique. In hearts from 17 adult cadavers, we measured: pulmonary trunk diameter at the leaflet tops (D1). H1 and H2 were respectively from leaflet top to lower and upper levels of the pulmonary trunk bifurcation. D2 = 1.4 D1 was calculated as the monocusp size allowing a 45 degrees opening of the valve and thus permitting good valvular efficacy. G = H1 - D2 determined the feasibility of the technique: G greater than 10 mm, appeared the most favorable, G between 0 and 10 mm, appeared possible, and G less than 0, appeared to be impossible. Mean values of D1, H1 and H2 were respectively: 20.19 mm, 37 mm and 57 mm. The technique was possible in 16 cases (94%) and impossible in 1 case (6%). Preoperative determination of these parameters, by echocardiography or magnetic resonance imaging, appears necessary before applying this new surgical technique.

Management of pseudoaneurysm of the ascending aorta performed under circulatory arrest by port-access

Pseudoaneurysms of the ascending aorta following previous thoracic surgery pose a difficult surgical management problem. In this report, we present a case of a patient with aortic insufficiency and a pseudoaneurysm of the ascending aorta at the site of a previous anastomosis. The particularity of this case is in the atypical use of Port-Access technology (Heartport, Redwood City, CA) to overcome surgical concerns [1].

[Effect of aortic valve replacent for aortic stenosis on cervical arterial blood flow]

Aortic stenosis is known to modify initial upstroke time (IUT) of velocity in peripheral arteries and carotid velocities. The authors conducted a prospective study in 30 patients scheduled for aortic valve replacement for aortic stenosis. The goal was to establish postoperative correction of carotid flow disorders. In the preoperative period, a positive correlation (p < 0.01) was observed between IUT and mean pressure gradient, and a negative correlation (p < 0.02) between IUT and aortic valve area. Post-operatively, the authors observed a large decrease (p < 0.0001) of IUT, and higher (p < 0.05) systolic peaks of velocity (PSV) in all studied arteries. In this article, the authors confirmed the few previous studies which described preoperative velocity modifications in aortic stenosis population, but they also described for the first time their postoperative correction. Therefore, identifying these patterns of peripheral circulatory alterations is important and underestimation of carotid stenosis, currently estimated preoperatively, must be avoided.

Endovascular repair of aortic allograft aneurysmal degeneration: a case report

Aortoenteric graft fistula remains a dreadful complication of aortic surgery. Good results have been reported using in situ graft replacement with arterial allografts. Late aneurysmal degeneration of the graft itself may necessitate further repair. We report the case of such an aneurysmal degeneration 7 years after implantation of the allograft. Endovascular repair was performed with a Vanguard device; complete exclusion was obtained immediately. At 6-month follow-up, the patient was alive and well. Duplex and computed tomography scans showed an excluded aneurysm with a slight reduction in size. Endovascular stent grafting may be a therapeutic option for treating patients with late allograft degeneration.

[Human valvular substitutes for the treatment of complex progressive endocarditis. Application to aortic, mitral and tricuspid valves]

The aim of this study was to assess the immediate and long-term results of human valvular substitutes (homografts and autografts) in the treatment of complex progressive endocarditis in aortic, mitral and tricuspid valves. Since 1992, 80 patients (64 men, 16 women) aged 44 +/- 16 years (range 15 to 76 years), were treated. In 53 patients, the endocarditis involved native valves, 4 on previously plastified valves, or prosthetic valves in 27 patients. The endocarditis was recurrent 6 patients. The lesions were situated on the aortic valve (N = 59), mitral valve (N = 5), aortic and mitral valves (N = 12), aortic and tricuspid valves (N = 3), mitral and tricuspid valves (N = 1). The peroperative findings confirmed the lesions diagnosed at echocardiography: prosthetic valve dehiscence (27 patients), prosthetic cusp tear (N = 7), vegetations (N = 61), perforations (N = 48), periannular abscess (N = 47), aorto-ventricular discontinuity (N = 12), aorto-mitral discontinuity (N = 7), right ventricular aortic fistula (N = 1), aorto-pulmonary fistula (N = 1), pseudo-aneurysm (N = 1), ventricular septal defect (N = 1). Eighty-six human valvular substitutes were used (double homograft in 6 patients): aortic homograft (N = 63), pulmonary in the aortic position (N = 1), the mitral position (N = 12), of which 8 were in the mitral and 4 in the tricuspid position, pulmonary autograft (N = 10). Ten mitral valve repairs were performed on infected lesions. Associated procedures included mitral valve repair (N = 5), tricuspid valve repair (N = 1) for non-infarcted valve lesions, replacement of the ascending aorta (N = 2), the aortic arch (N = 1), coronary bypass surgery (N = 2) and one nephrectomy. The hospital mortality was 5% (4 patients). The causes of death were: infarction (N = 2), myocardial failure (N = 1) and multiorgan failure (N = 1). Four early reoperations were required for technical problems, none for endocarditis. Seventy-three of the 76 survivors were followed up for 43 +/- 24 months (range 1 to 84 months). Eight patients died during follow-up, but only 1 of cardiac causes (operation for recurrent endocarditis in a drug abuser). Seven operations were performed, 3 for technical problems or structural failure, 4 for recurrent endocarditis. At 5 years' follow-up, the survival was 81 +/- 5%; 88 +/- 6% of patients were free of endocarditis, 77 +/- 6% had no reoperation: no patient had thromboembolic complications. These results show that human valvular substitutes are adapted for the treatment of complex, progressive aortic, mitral and tricuspid valve endocarditis when techniques of valvular repair are no longer feasible.

Coronary reoperations: indications, techniques and operative results. Retrospective study of 240 coronary reoperations

BACKGROUND

We review twelve-year experience with coronary reoperations so as to better identify indications, techniques and results.

METHODS

Between January 1986 and March 1998, 240 coronary reoperations (228 redux, 12 tridux) were performed. There were 223 male and 17 female patients, with a mean age of 63.6+/-7.9 years at the time of reoperation. Mean time interval between operations was 10+/-4.8 years. Symptomatology consisted of: stable recurrent angina (40%), unstable (57%), or congestive heart failure (3%). Pathological feature of the primary grafts was implicated in 95% of cases and atheroma sole progression over native network in 5% of cases. During reoperations 521 (2.2+/-0.8/patient) bypass [venous (40%), arterial (60%)] were performed as well as 15 associated procedures.

RESULTS

Operative mortality represented 10% (n=24). Causes of death included infarct (7), left ventricular failure (12), rhythm disorders (2), mediastinitis (1) and multiorgan failure (2). Mortality risk factors were operation date (16.6% before 1992 and 7.4% after, p=0.03), age (13.1% after 60 years old, 2.7% before, p=0.01) time interval between intervention (12% after 8 years, 4% before, p=0.05) and anterograde cardioplegia only (11.8% versus 4.5% when a combined anterograde and retrograde access was used, p=0.06). Morbidity was 31% (71/240). Among the survivors 169 patients (78%) did not experience any complication.

CONCLUSIONS

Thanks to a better medico-surgical management, the mortality rate of coronary reoperations is steadily decreasing.

Bilateral carotid dissection and factor V mutation: a second case

A young woman 38 years of age underwent Doppler ultrasonography following the spontaneous appearance of cervical pain causing loss of sleep. The examination revealed bilateral dissection of the internal carotid arteries, confirmed by supraaortic arteriography. Two successive CT scans showed no cerebral lesions. A thrombosis of the great saphenous vein was recorded as the only vascular event in her medical history. Thrombophilia was assessed following discovery of the dissection, and upon examination a heterozygotic mutation of Factor V Leiden was revealed. This observation is the second case of carotid dissection occurring in a subject presenting a factor V mutation. At the present time, however, there are no results to justify the assumption of a direct link between these two pathologies.

Temperature-dependent basal tone in isolated human saphenous veins: implication of TP-receptors

Cutaneous blood vessels are very sensitive to changes in environmental temperature. The influence of variations in local temperature on the mechanisms involved in the basal tone, present in isolated human saphenous veins has not yet been studied. In the present study, segments with and without endothelium of human saphenous veins obtained from coronary bypass surgery patients were mounted for isometric tension recording in oxygenated physiological salt solution (PSS). After stabilisation of the basal tone, the local temperature was rapidly either decreased from 37 degrees C to 24 degrees C (cooling) or increased from 37 degrees C to 42 degrees C (warming). When antagonists or inhibitors were used the preparations were incubated for 30 min with the drugs. During basal conditions, cooling caused relaxations of the saphenous vein segments with endothelium and warming caused contractions; the absence of the endothelium did not modify these responses. In veins without endothelium, the warming-induced contractions were significantly inhibited by verapamil (10 microM) and by the antagonist of TP-receptors (receptors for thromboxane A2) Bay u 3405 (1 microM). The warming induced contractions were not affected by cyclooxygenase or lipoxygenase inhibition. At 37 degrees C, the isoprostanes (8-iso-PGE2 and 8-iso-PGF2alpha) induced potent contractions that were significantly inhibited by Bay u 3405 (1 microM). The data show that a basal tone is present in isolated resting human saphenous vein segments at 37 degrees C. This basal tone is decreased by local cooling and enhanced by local warming and is not dependent on the presence of the endothelium. The warming-induced contraction of the veins is mediated by a non-cyclooxygenase, non-lipoxygenase metabolite (isoprostane?) that interacts with TP-receptors and via an extracellular calcium-dependent pathway.

Effect of chronic treatment with the inducible nitric oxide synthase inhibitor N-iminoethyl-L-lysine or with L-arginine on progression of coronary and aortic atherosclerosis in hypercholesterolemic rabbits

BACKGROUND

We examined the implications of iNOS in atherosclerosis progression using the selective inducible NO synthase (iNOS) inhibitor N:-iminoethyl-L-lysine (L-NIL) in hypercholesterolemic rabbits.

METHODS AND RESULTS

Nine rabbits were fed a 0.3% cholesterol diet for 24 weeks (Baseline group); 25 animals were maintained on the diet and treated for 12 extra weeks with L-NIL (5 mg x kg(-1) x d(-1), L-NIL group, n=8), vehicle (Saline group, n=9), or L-arginine (2.25%, L-Arg group, n=8). In abdominal aortas of Saline rabbits, the lesions (53.7+/-5.7%, Baseline) increased to 75.0+/-5.0% (P:<0.05) but remained unaltered in the L-NIL group (63. 4+/-6.6%). Similar results were obtained for the intima/media ratio in thoracic aortas. In coronary arteries, the intima/media ratio was comparable in Baseline (0.68+/-0.18) and Saline (0.96+/-0.19) rabbits but decreased to 0.34+/-0.19 (P:<0.05) in L-NIL rabbits. L-Arginine had beneficial effects only in abdominal aortas. An increased thoracic aorta collagen content was found in Saline and L-Arg but not in L-NIL rabbits. In thoracic aortas of the Saline group, acetylcholine caused modest relaxations that slightly increased by L-arginine but not by L-NIL. Relaxations to nitroglycerin were ameliorated by L-NIL.

CONCLUSIONS

This is the first study showing that chronic treatment with an iNOS inhibitor, L-NIL, limits progression of preexisting atherosclerosis in hypercholesterolemic rabbits. Increased intimal collagen accumulation may participate in iNOS-induced atherosclerosis progression.

Is 10 minutes the optimum immersion time in 0.6% glutaraldehyde for human pericardium?

BACKGROUND AND AIM OF THE STUDY

Pericardial fixation with 0.6% glutaraldehyde is usually assessed by measuring the shrinkage temperature of the tissue: the higher the shrinkage temperature, the greater the degree of cross-linking induced between collagen molecules. Animal pericardium studies have shown maximum response to be obtained after brief immersion (10 min). Our aim was to evaluate the effect of glutaraldehyde immersion time on shrinkage temperature of human pericardium which, to our knowledge, has not yet been studied.

METHODS

Pericardial strips were harvested from 40 patients undergoing cardiac surgery. Time of immersion in glutaraldehyde ranged from 3 min to 6 months. Fresh untreated human pericardium samples were used as controls. The relationship between shrinkage temperature and time of treatment with glutaraldehyde was studied using a regression analysis.

RESULTS

Glutaraldehyde treatment of pericardial tissues caused an increase in shrinkage temperature that was related biphasically to the time of immersion in glutaraldehyde. Mathematical expression of this curve permitted glutaraldehyde immersion time to be evaluated in relation to the degree of optimal shrinkage temperature. The time required for optimal fixation with glutaraldehyde, as measured by shrinkage temperature, was 100+/-0.77 min.

CONCLUSION

Our results suggested that a 10-min exposure to glutaraldehyde was insufficient for 'correct' fixation of human pericardium. Inadequate glutaraldehyde exposure of human pericardium may explain mid and long-term failures reported with this tissue in cardiac surgery.

[Utilization of aortomyoplasty as a biological pumping system]

Aortomyoplasty is a surgical technique of constructing a neo-ventricle on the ascending or descending aorta with the latissimus dorsi muscle. This is electrically stimulated to contract during diastole, thereby creating a system of chronic, haemo-compatible aortic pumping. Long-term experimental studies have shown increases in cardiac output (from 3.6 to 5.5 l/min), decreases in peripheral resistances (from 1574 to 1134 dyne.sec.cm-5) and increases in indices of subendocardial viability (DPTI/TTI: 1.1 to 1.4). These experimental studies have been confirmed by the initial clinical results. To date, world experience includes thirty-six patients. With cardiomyoplasty, aortomyoplasty is a new arm in the therapeutic arsenal against severe cardiac failure by providing a new system of chronic circulatory assistance which is implantable and biocompatible.

Influence of coronary artery and contralateral carotid artery status on long-term results of carotid artery surgery

The main cause of death and long-term disability of patients undergoing carotid artery surgery is coronary artery disease. To identify the prognostic value of the status of the contralateral artery, we studied the course of 224 consecutive patients in whom one or both carotid arteries were operated on at our institution between 1985 and 1995. The 224 patients were divided into three groups: group I (n = 56) had an occluded contralateral carotid artery, in group II (n = 56) both carotids were operated on, and group III (n = 112) had a normal contralateral carotid artery. The clinical status of all patients except one was ascertained by one of us. We found that the status of the contralateral artery does not influence the long-term prognosis of patients undergoing carotid artery surgery. A periodic cardiological and vascular follow-up of these patients seems warranted to improve their survival.

[Cardiac fibroelastoma. Six operated cases and review of the literature]

The authors reviewed the cases of 6 patients operated between September 1994 and February 1999 for a rare benign tumour: papillary fibroelastoma of the heart. These patients, aged 51 +/- 14 years, all have single valvular involvement: mitral (N = 3), aortic (N = 2), tricuspid (N = 1). Five patients were symptomatic: transient ischaemic cerebral events (N = 3) associated with mesenteric infarction requiring ileal resection in 1 case; constituted cerebrovascular accident (N = 1); syncope (N = 1). In this last patient, the fibroelastoma was diagnosed fortuitously on the tricuspid valve. The features and location of the tumours were determined by transoesophageal echocardiography. Surgical treatment in all patients consisted in excising the tumour and preserving the valve. One aortic cusp was reconstructed after excising the tumour with a cryopreserved partial aortic homograft. Peroperative transoesophageal echocardiography confirmed the absence of regurgitation after the procedures in all patients. There were no postoperative complications in any of the cases. No cases of valvular regurgitation or of tumour recurrence were observed during follow-up. Despite the benign histology, cardiac fibroelastomas should be excised because of their embolic complications. Absence of recurrence justifies conservative reconstruction of the affected valve.

Upper limb ischemia after subclavian flap aortoplasty: unusual long-term complication

Repair of isolated coarctation of the aorta by subclavian flap aortoplasty carries the disadvantage of impaired blood supply to the left arm. However, ligation of branches of the subclavian artery can be tolerated without manifest ischemia of the upper extremity. We report the case of a young man who suffered from left upper extremity ischemia 18 years after initial operation. Treatment consisted of carotid-subclavian bypass with good outcome. The surgical approach of coarctation by subclavian aortoplasty should be reserved for specific cases, and if this procedure is performed, ligation of branches of the subclavian artery should be minimized to increase inflow into the left brachial artery.

[Metaplasia of aortic tissue into tracheal tissue. Surgical perspectives]

Tracheal reconstruction after extensive resection remains an unsolved surgical problem. Numerous attempts have been made using tracheal grafts or prosthetic conduits with disappointing results. In this study, we propose a new alternative using an aortic autograft as tracheal substitute. In a first series of experiments, a half circumference of two rings was replaced with an autologous carotid artery patch. In a second series, a complete segment of trachea was replaced with an autologous aortic graft supported by an endoluminal tracheal stent. No dehiscence or stenosis was observed. Microscopic examinations at 3 and 6 months showed the replacement of the aortic tissue by tracheal tissue comprising neoformation of cartilage and mucociliary or non-keratinizing metaplastic polystratified squamous epithelium. Although these results need to be confirmed by a larger series of experiments, they showed that a vascular tissue placed in a different environment with a different function can be submitted to a metaplastic transformation which tends to restore a normal structure adapted to its new function. These remarkable findings offer new perspectives in tracheal reconstruction in human.

Platelets and prostacyclin in arterial bypasses: implications for coronary artery surgery

BACKGROUND

We investigated effects of platelets and prostacyclin formation in human internal mammary (IMA) and radial (RA) arteries.

METHODS

IMA and RA segments were suspended in organ bath with increasing concentrations of platelets. Experiments were applied with and without ketanserin, a 5HT2 receptor antagonist, or U3405, a TXA2 receptor antagonist. The release of prostacyclin (PGI2) was assessed by enzyme immunoassay in vessels without endothelium, before and after contraction with angiotensin (AT) I-II.

RESULTS

In IMA and RA with endothelium, platelets caused contractions, significantly enhanced in arteries without endothelium. Contractions to platelets were higher in RA than in IMA. U3405 reduced the platelet induced contractions in RA but not in IMA. Ketanserin inhibited the platelet induced contractions in IMA and RA. The basal release of PGI2 was more important in IMA than in RA. Addition of AT/I-II significantly reduced the release of PGI2 in IMA but not in RA.

CONCLUSIONS

The RA responds more powerfully to platelets than IMA. Protective system with PGI2 seems to be more powerless in RA than in IMA. This accentuates the importance of antispastic and antiplatelet drugs when arteries are used for coronary artery bypass surgery.

Histochemical evidence for inducible nitric oxide synthase in advanced but non-ruptured human atherosclerotic carotid arteries

In response to cytokine stimulation, the inducible isoform of the nitric oxide synthase (iNOS) produces large amounts of nitric oxide with potential consequences in the pathophysiology of atherosclerosis. Previous investigations have demonstrated the presence of iNOS in human atherosclerotic lesions. The goal of this study was to evaluate the occurrence of the expression of iNOS in ruptured versus non-ruptured human carotid atherosclerotic plaques. Using plastic-embedded sections, we performed in situ hybridization and immunohistochemistry on very advanced atherosclerotic lesions type V (non-ruptured) and type VI (ruptured) from 12 atheromatous carotid arteries from endarterectomy and six non-atherosclerotic internal mammary arteries from aorto-coronary bypass. Only one internal mammary artery expressed iNOS in the endothelium. In contrast, iNOS mRNA and protein were repeatedly expressed in advanced lesions type V in 5/7 cases, particularly in inflammatory regions. Specific cell markers identified iNOS-positive cells as macrophages and T-lymphocytes but also as smooth muscle cells and endothelial cells adjacent to these inflammatory regions. Nitration of protein tyrosines was not always associated to iNOS expression but more likely to the presence of inflammatory cells. In complicated lesions type VI, the occurrence of iNOS mRNA and protein expression diminished drastically (1/5 cases). Combined expression of iNOS mRNA and protein is frequently found in advanced but non-ruptured human atherosclerotic carotid lesions while it becomes rare after the plaque has ruptured. These findings suggest that iNOS could be an active participant in the plaque rupture event.

Tolerance induced without immunosuppression in a T-lymphocyte suicide-gene therapy cardiac allograft model in mice

BACKGROUND

Life-long immunosuppression is a major cause of mortality and morbidity in transplant recipients. Gene therapy could provide new ways to obtain tolerance and avoid indefinite immunosuppression. EpTK mice are derived from the FVB/N strain (H2q) and express the thymidine kinase gene of herpesvirus in all mature T cells. Thus any mature dividing T cell can be killed in the presence of ganciclovir. We investigated the survival of alloincompatible C57B1/6 (H2b) hearts heterotopically transplanted into EpTK mice given only ganciclovir from day 0 to day 7 or 14.

METHODS

Abdominal cardiac transplantations were performed in 22 control mice (untreated FVB [n = 15], ganciclovir-treated FVB [n = 5], and untreated EpTK mice [n = 2]) and in 28 EpTK mice given ganciclovir from day 0 to day 7 (n = 15) or day 14 (n = 13). Rejection was defined as complete cessation of cardiac beat. Histologic examination of the grafts was performed at rejection, at day 7, or at day 100. Lymphocyte proliferation assays (concanavalin A stimulation or mixed lymphocyte reaction) were performed at day 7 and at day 100.

RESULTS

All control animals rejected transplants in 7 days (range, 5-9 days), whereas indefinite survival (>100 days) was observed in 89% of the ganciclovir-treated EpTK group, irrespective of the duration of ganciclovir treatment. Graft histology showed extensive cellular infiltrates with myocyte necrosis and arteritis in the control animals but only a mild infiltrate without necrosis or arteritis in the ganciclovir-treated EpTK group. The proliferative responses of the tolerant mice at day 100 were identical to those of naive mice, including a preserved proliferation against the donor's lymphocytes in mixed lymphocyte reaction.

CONCLUSION

Functional transplantation tolerance of a fully incompatible heart can be achieved without immunosuppressive drugs in this model of suicide gene therapy.

Decreasing occupational risk related to blood-borne viruses in cardiovascular surgery in Paris, France

BACKGROUND

Surgeons face the risk of patient-to-physician transmission of blood-borne viruses. This risk is related to the seroprevalence of the viruses in the patient population.

METHODS

The seroprevalence of the human immunodeficiency virus, hepatitis B virus, and hepatitis C virus were determined in cardiovascular patients at Hôpital Broussais in Paris, France, over a 5-year period (1994 to 1998).

RESULTS

Hepatitis C virus is the most prevalent virus in the patient population, whereas human immunodeficiency virus is the least frequent. The seroprevalence of hepatitis C virus and human immunodeficiency virus has decreased over time, whereas hepatitis B virus has remained constant. We apply the seroprevalence data to a mathematical model to estimate the occupational risk of seroconversion faced by surgeons over the length of their career. Our results show that the principal risk faced by the surgeon arises from hepatitis B virus and hepatitis C virus. The decreasing seroprevalence of the hepatitis C virus has resulted in a decrease in the occupational risk.

CONCLUSIONS

The probability of becoming infected with a blood-borne virus over the career of the surgeon is notable. The greatest occupational risk to the surgeon is from the hepatitis viruses and not HIV.

Single breath exhaled nitric oxide in lung transplant patients: a preliminary clinical study

Exhaled nitric oxide is considered as a marker of airway inflammation. We report here our preliminary experience with single-breath exhaled nitric oxide measured in lung transplant patients with and without bronchiolitis obliterans syndrome and in cardiac transplant patients. Peak and end-expiratory nitric oxide concentrations did not differ between groups, but single-breath exhaled nitric oxide recordings were strikingly different in patients suffering from bronchiolitis obliterans syndrome, with a slower decrease from peak to end-expiratory nitric oxide concentration. Further studies are required in order to determine whether theses abnormalities reflect the inflammatory process of bronchiolitis obliterans syndrome.

Comparison of the acute hemodynamic effects of hypertonic or colloid infusions immediately after mitral valve repair

OBJECTIVE

To determine the acute hemodynamic effect of hypertonic saline and/or colloid solutions as volume resuscitation in postoperative mitral valve repair patients.

DESIGN

Prospective, randomized trial.

SETTING

Postoperative cardiac intensive care unit of Broussais Hospital.

PATIENTS

Twenty-six patients who underwent mitral valve repair were prospectively studied. Two patients were excluded during the study.

INTERVENTIONS

During the immediate postoperative period, when wedge pressure decreases to <8 mm Hg, patients were randomly assigned to receive 250 mL of either hypertonic saline 7.2%-hydroxyethyl starch 6% (molecular weight, 200,000; hydroxyethylation ratio, 0.5) solution (HS-HES group), hypertonic saline 7.2% solution (HS group), or hydroxyethyl starch 6% solution (HES group). The infusion was completed within 15 mins. No additional volume was infused throughout the study.

MEASUREMENTS AND MAIN RESULTS

Standard hemodynamic measurements and echocardiographic data demonstrated that HS-HES and HS induced a higher increase in left ventricular end-diastolic area than HES. In the HS-HES and HS groups, systemic vascular resistances decreased significantly and end-systolic area tended to decrease. In the HES group, systemic vascular resistances did not change and end-systolic area tended to increase. Accordingly, ejection fraction increased significantly by 21% and 18% with HS-HES (from 50.5 +/- 5.5 to 61.2 +/- 4.8) and HS (from 49.7 +/- 3.6 to 58.8 +/- 3.3), respectively, and did not change with HES. A major increase in cardiac index was observed after hypertonic solutions infusion, from 2.9 +/- 0.3 to 4.1 +/- 0.4 L/min/m2 in the HS-HES group and from 2.7 +/- 0.3 to 3.8 +/- 0.4 L/min/m2 in the HS group. Then, cardiac index progressively returned to baseline values within the 3 hrs after the infusion. No significant difference was observed between HS-HES and HS. In these groups, plasma sodium increased significantly after the infusion and remained higher than baseline values throughout the study. Adverse events were observed only with hypertonic solution administration: hypotensive episodes, sudden increases in pulmonary capillary wedge pressure, and ventricular arrhythmias. These side effects are likely attributable to a too-high dose and/or rate of infusion. All patients included in the study were discharged from the hospital before the 10th postoperative day.

CONCLUSION

We conclude that in patients who have undergone mitral valve repair, postoperative infusion of hypertonic saline solutions increases left ventricular preload and left ventricular ejection fraction. The use of these hypertonic solutions may be of interest in patients with valvular cardiomyopathy. A titrated dose and a low rate of infusion may substantially improve the safety.

[Do the long-term results of carotid surgery influence the status of the contralateral carotid artery?]

AIM

The main cause of long-term death and disability of patients undergoing carotid artery surgery is coronary artery disease. To identify the prognostic value of the status of the contralateral artery, we studied the course of 224 patients operated consecutively on one or both carotid arteries in the same institution between 1985 and 1995.

PATIENTS AND METHODS

The 224 patients were divided into three groups: group I (n = 56) having an occluded contralateral carotid artery; group II (n = 56) in which both carotids were operated on; and, group III (n = 112) having a normal contralateral carotid artery. The clinical status of all patients was ascertained by one of us for all patients except one. This study concerned also the course of 40 patients (group R) belonging to the three groups, who had during the follow-up period a coronary and/or a peripheral vascular intervention with a preoperative coronarography.

RESULTS

The median follow-up was 62.8, 78 and 65 months for groups I, II and III, respectively. Actuarial survival rates were 67%, 73%, 72.5% at 5 years, and 39%, 51.5% and 42% at 10 years, for group I, II and III respectively. Actuarial stroke-free rates were 96%, 100%, 91% at 5 years, and 96%, 100% and 78.5% at 10 years for group I, II and III respectively. Actuarial cardiac death rates were 26%, 23%, 19% at 5 years, and 49%, 42% and 37% at 10 years for group I, II and III, respectively. None of the differences between the three groups regarding these three different end-points was significant. The group R fatal or non-fatal cardiac event-free rates at 5 and 10 years were 88% and 53% respectively. When compared with the rates of other patients (without revascularization): 68% and 25.5% at 5 and 10 years, the results were almost significant (P = 0.07). Average age for group R patients was significantly lower (65 vs. 69 years, P < 0.05). Using Cox's model, age alone emerged as a factor influencing survival (P = 0.07) but not revascularization (P = 0.13).

CONCLUSION

The status of the contralateral artery does not influence the long-term prognosis of patients undergoing carotid artery surgery. A periodic cardiological and vascular follow-up of these patients tends to improve their survival.

Video-assisted replacement or bypass grafting of the descending thoracic aorta with a new sutureless vascular prosthesis: an experimental study

PURPOSE

The feasibility of the video-assisted insertion of a new sutureless vascular prosthesis was studied.

METHODS

Seven sheep, weighing 25 to 35 kg, were operated on under general anesthesia. The animals were intubated with a single-lumen endotracheal tube and placed in the right lateral decubitus position. A thoracoscope was introduced in the 11th intercostal space, and a minithoracotomy (4 to 5 cm) was performed in the seventh intercostal space. After retraction of the lung, a short segment (10 cm) of the descending thoracic aorta was exposed. Our prosthesis was made of Dacron and was specifically designed to be inserted without a suture. After systemic heparinization, the aorta was cross-clamped with two vascular clamps introduced into the thoracic cavity through two 5-mm thoracic incisions. The aorta was either replaced (five cases) or bypass grafted (two cases). At the completion of the procedure, blood pressure was pharmacologically increased (5 mg intravenous bolus of epinephrine), and each anastomosis was checked for bleeding. All animals were killed, and the prosthesis was retrieved for macroscopic examination.

RESULTS

The procedure was completed in each case without extension of the minithoracotomy. Insertion of the prosthesis was easy and fast, and completion of each anastomosis required 10 to 15 minutes. A 3- to 4-mm space between each clip was sufficient for proper attachment. All procedures were performed in less than 120 minutes. No bleeding was observed at the level of each anastomosis, even when a sustained high blood pressure was induced. The proper insertion of the prosthesis and the absence of any anastomotic stenosis was confirmed by means of macroscopic examination.

CONCLUSION

Video-thoracoscopic replacement or bypass grafting of the descending thoracic aorta was easy with this new sutureless vascular prosthesis. Minimally invasive vascular surgery might be facilitated with such a prosthesis. However, long-term animal studies are required before human implantation can be undertaken.