Surgical extraction after thrombosis around the Avalon dual lumen cannula

The use of a dual lumen cannula (DLC) for venovenous extracorporeal membrane oxygenation (ECMO) has several advantages and reports of complications are rare. We present a case of thrombosis around and inside the Avalon Elite™ bicaval DLC (Avalon Laboratories, Rancho Dominguez, CA, US), for which simple removal by retraction was impossible. A 30-year-old man had experienced an unstable C6/7 fracture with spinal contusion and haematoma in the spinal canal with incomplete neurological paraplegia and thoracic trauma. He developed acute respiratory failure due to posttraumatic systemic inflammatory response syndrome and venovenous extracorporeal membrane oxygenation (ECMO) support was indicated. The cannulation was performed with an Avalon Elite™ cannula (31Fr) in the right jugular vein under fluoroscopy. After 18 days of ECMO therapy, despite the continuous administration of heparin (400iu/h), ECMO was discontinued because of the formation of a massive thrombus in the oxygenator. At that time, the patient's haemodynamic and respiratory parameters were stable, and we were able to induce a rapid weaning from ECMO. The surgical removal of the cannula became necessary and was performed using a small neck incision without complications. We report this case to emphasise that any resistance encountered during an attempt to extract the Avalon Elite™ cannula may cause serious complications. In such cases, surgical removal must be considered.

Acute pulmonary edema after a single oral dose of acetazolamide

INTRODUCTION

Anaphylactic shock and pulmonary edema are unusual but life-threatening adverse reactions to drugs. We encountered a case of serious anaphylactic shock and acute pulmonary edema caused by a single oral intake of acetazolamide, a frequently used medication by several medical specialties especially in ophthalmology.

CASE PRESENTATION

An 80-year-old female was admitted to our emergency Coronary Unit presenting symptoms and signs of shock with acute pulmonary edema. Patient was hospitalised at the Opthalmological Department with intention to undergo cataract surgery. Approximately, four hours before operation, half a tablet of acetazolamide 250 mg was given, in order to control her pre-operative intraocular pressure. Half an hour later, she complained of nausea, became cyanotic, and suffered acute respiratory failure with characteristic massive pulmonary edema. Ventilatory support was initiated and O2 saturation increased to 89%. She was administered 2 ampoules of intravenously furosemide. The blood chemistry panel was normal, as well as myocardial cytolysis tests. Chest radiograph showed enlarged cardiothoracic index, ill-defined vessels, peribronchial cuffing, alveolar edema. An echocardiogram showed normal atria and ventricles, normal systolic function, and excluded pulmonary hypertension. Furosemide (40 mg/IV, S: 1x3) and oxygen (8 Lt/min) were administered for the following 24 hours. Clinical improvement was seen and the O2 saturation was normalized. ECG controls were normal. The patient experienced a full recovery and was discharged 3 days later.

CONCLUSION

The relationship between anaphylactic shock with acute pulmonary edema and acetazolamide seems highly probable in this case, considering the short time between drug assumption and onset of symptoms (about 30 minutes) and the absence of previous diseases to which symptoms could be related. The patient was not previously treated with acetazolamide. Nowadays, the clinical use of acetazolamide is very limited. Its principal uses are in the preoperative treatment of closed angle glaucoma and continuative therapy of open angle glaucoma.

TLR4 gene polymorphisms: evidence for protection against type 2 diabetes but not for diabetes-associated ischaemic heart disease

OBJECTIVE

Several factors either predisposing or protecting from the onset of diabetes mellitus type 2 (DM2) have been proposed. Two specific polymorphisms of toll-like receptor 4 (TLR4; Asp299Gly and Thr399Ile) have recently been identified either as candidate protector genes against DM2 and associated neuropathy or risk alleles for the manifestation of diabetic retinopathy. The impact of these alleles on the risk for ischaemic heart disease (IHD) is controversial while their role in diabetes-associated IHD has never been studied.

DESIGN AND METHODS

In order to clarify the potential impact of TLR4 polymorphisms on the predisposition for DM2 as well as on diabetes-related IHD vulnerability, the distribution of the mutant TLR4 Asp299Gly and Thr399Ile alleles in 286 DM2 patients and 413 non-DM2 controls with or without IHD, was examined.

RESULTS

Mutant alleles were predominantly detected in 79/413 non-diabetic individuals versus 15/286 DM2 patients (P<0.0001). The rates of positivity for mutant alleles were similar among diabetic patients with or without IHD (7/142 vs 8/144, P>0.1), whereas they proved different among non-diabetic individuals with or without IHD (39/145 vs 40/268, P=0.004). Following multivariate analysis, the difference between diabetic and non-diabetic subjects, with regard to TLR4 mutations alone, remained significant (P=0.04).

CONCLUSIONS

Mutant TLR4 alleles confer protection against DM2. However, their presence does not seem to play any role, protective or aggravating, in the manifestation of IHD either in diabetic or in non-diabetic individuals.

Successful thrombolysis of right atrial and ventricular thrombi in a patient with massive pulmonary embolism

Right sided heart thrombi may develop within the right heart chambers or they may be peripheral venous clots that on their way to the lungs, accidentally lodge in a patent foramen ovale, tricuspid chordae or Chiaris network. Type A thrombi have a worm-like shape and are extremely mobile. These pleomorphic thrombi are mainly localized in the right atrium, frequently move back and forth through the tricuspid orifice and may cause cardiovascular collapse when entrapment occurs. Type B thrombi attach to the atrial or ventricular wall indicating that they are probably of local origin. We describe the case of a middle age man (48 years old) with no cardiovascular history and a massive pulmonary embolism where transthoracic echocardiography revealed many type A thrombi in both right atrium and ventricle. He presented with acute dyspnea, diaphoresis and hemodynamical instability. He was treated with thrombolysis and after three hours was greatly improved and the thrombi were disappeared. After ten days of hospitalization he was discharged. Thrombi were originated in the popliteal region of the inferior vena cava of both legs and were totally treated.

Surgical complications of hyperglycaemia

We review the mechanisms leading to hyperglycaemic damage and draw functional extrapolations aiming to an improved management of surgical complications, which are common among diabetic patients.

[Subjective theories of illness in the Greek culture]

In this cross-sectional study, 100 Greeks were asked about their lay theories for cancer and myocardial infarction via a standardized questionnaire. Most Greeks questioned are to some extent informed about both diseases and receive their information from the media. In contrast to the epidemiologic data, the results of this study show that the Greeks questioned only rarely know of relatives suffering from myocardial infarction, but have often experienced close relatives with cancer. As a possible pathogenesis they believe in a combination or interaction of psychological and somatic components. Most of them are more likely to think of cancer as a disease with somatic causes while myocardial infarction is more often held to be psychologically evoked. Main causal attributions are unhealthy way of life, pollution and predisposition. Negative environmental factors are thought of as the leading cause of cancer, while psychosocial stress is thought to be the leading cause of myocardial infarction. Both diseases are believed to be very dangerous. However, the Greeks questioned believe in better chances for prevention and therapy of myocardial infarction than of cancer. With respect to subgroup analyses, education shows the most important influence: Better educated subjects show a significantly stronger internal and less fatalistic orientation than the less educated Greeks. The males questioned are more likely to hold psychosocial factors responsible for the onset of myocardial infarction and thus are more internally oriented than their female counterparts. The older Greeks tend to believe significantly stronger in external causes like negative environmental factors and negative aspects of life than the younger Greeks of the sample.

Minimally invasive aortic valve replacement (AVR) compared to standard AVR

OBJECTIVES

Minimally invasive cardiac surgery has been developed to offer patients the benefits of open heart operations with decreased pain and limited skin incision. A limited superior median sternotomy has been shown to provide a good exposure for aortic valve replacement (AVR) and good results. In this study we report the results of minimally invasive AVR compared to standard sternotomy AVR performed in the same period.

METHODS

From May 1996 to January 1998, 86 patients received isolated aortic valve replacement by the limited superior median sternotomy(group 1). As a control group (group 2), 78 patients were enrolled who underwent isolated aortic valve replacements by standard sternotomy in the same period.

RESULTS

Median ischemic time and median bypass time between the two groups showed no significant difference (P > 0.05). Median entire operation time in group 1 was obviously shorter than that in group 2 (P < 0.01). Median postoperative drainage was 229 ml in group 1, 369 ml in group 2. The difference between the two groups (P < 0.05) was significant. Median postoperative respiratory support time was 7.43 h in group 1, 11.26 h in group 2, with significant difference (P < 0.05). Median duration of hospital stay were 6.2 days in group 1, 9.4 days in group 2, with significant difference (P < 0.01). Reoperations for bleeding were two in group 1, four in group 2, superficial wound infection and sternum disruption occurred once in group 1 and four times in group 2. There were two hospital deaths respectively in the two groups (not procedure related).

CONCLUSIONS

The limited superior median sternotomy provides good exposure to the left ventricular outflow tract, aortic valve, ascending aorta, and even to the mitral valve through the roof of the left atrium. Therefore it seems to be suitable for all kinds of aortic valve operations. Besides less pain, shorter skin incision, shorter respiratory support time and lower blood loss, it has more advantages as opening and closure of the sternum is faster; decreasing infection and disruption of the sternum, and finally decreasing the time required for hospitalization and recovery.

Early and intermediate results of left ventricular reduction surgery

OBJECTIVE

Left ventricular reduction surgery is a new surgical option for treatment of end-stage cardiac dysfunction, and little is known about hemodynamics and outcome in the European heart failure population. We present our early results with this operation.

METHODS

From January 1995 to September 1997, 30 patients (25 men, 5 women; mean age 61.2 years) underwent partial left ventriculectomy. The underlying disease was ischemic in 18 patients and idiopathic dilated cardiomyopathy in 12 patients. Preoperatively 23 patients were in New York Heart Association functional class IV and 7 were in class III. Mean cardiac index, stroke index and ejection fraction were 1.8 +/- 0.3 l/m2 per min, 23.5 +/- 5.1 ml/m2 and 19.3% +/- 6.8%, respectively. Associated procedures were coronary bypass in 18 patients, mitral valvuloplasty in one, aortic or mitral valve replacement in three, dynamic cardiomyoplasty in two, and left ventricular assist device implantation in 1.

RESULTS

There were two early deaths: one from bleeding and one from anticoagulant-related cerebral hemorrhage. Regarding late deaths, one patient died from pneumonia 3 months after the operation and two died from dysrhythmia 4 and 17 months postoperatively. The estimated 1-year survival rate calculated by the Kaplan-Meier log-rank method was 85%. Mean cardiac index, stroke index, and ejection fraction rose significantly (P = 0.0001) to 2.9 +/- 0.51/m2 per min, 36.9 +/- 6.2 ml/m2 and 37.8% +/- 9.2%, respectively. Currently 26 patients are in New York Heart Association functional class I or II.

CONCLUSIONS

Left ventricular reduction surgery improves objective and subjective parameters of cardiac performance significantly in early and intermediate follow-up. Randomized studies and carefully documented long-term results seem to be necessary to define the role of left ventricular reduction surgery.

Pediatric circulatory support

BACKGROUND

Mechanical circulatory support in infants and small children is still a crucial issue. Until recently technological advances have been limited to the adult population.

METHODS

Between February 1994 and December 1996, 553 infants or children underwent operation at our institution. Ten of them were treated with cardiac assist systems. Their ages ranged from 4 days to 8 years (median 5 months). In 8 patients we used a pulsatile circulatory support system available in 6 sizes (9, 10, 22.5, 25, 54, and 60 mL). A centrifugal pump was used in 2 additional infants. In 3 children cardiac assist was considered as a bridge to transplantation; in the remaining patients postcardiotomy failure or cardiogenic shock led to mechanical support.

RESULTS

Median duration of assist was 4 days (range 8 hours to 17 days). In all cases we could observe recovery of renal, hepatic, and cardiac function in the immediate postimplantation period. Six patients survived and could be discharged either after successful transplantation or after myocardial recovery from postcardiotomy failure. The cause of death in 4 cases was bleeding and multiorgan failure. No technical failures occurred with either system.

CONCLUSIONS

The pulsatile circulatory support system seems to be feasible and effective for pediatric extracorporeal support. If the anatomic situation does not permit implantation, centrifugal pumps are an alternative.

Stent implantation of the arterial duct in newborns with duct-dependent circulation

AIMS

Little is known about the medium term results after stenting of the arterial duct in neonates and infants with duct-dependent cyanotic congenital heart disease. We report the results of stent implantation of the arterial duct in 21 neonates and infants. The defects for which the arterial duct was stented included pulmonary atresia with intact ventricular septum, critical pulmonary stenosis, and more complex defects with associated reduced pulmonary blood flow.

METHODS AND RESULTS

Palmaz stents were used and successfully implanted in all the 21 patients. There were no major complications during the stent implantation procedure although two hospital deaths occurred 2 and 14 days after stent implantation. Cardiac catheterization was repeated electively 3 to 6 months after stent implantation. Stent stenosis due to intimal proliferation was noted in 11/13 patients who underwent recatheterization. Stenosis of the inner stent lumen ranged from 25% to 100%, mean 74%. Re-dilatation of the stent was required in five patients who were awaiting corrective surgery. In babies with pulmonary atresia or critical pulmonary stenosis, who also underwent additional balloon dilatation of the pulmonary valve, spontaneous closure of the stented arterial duct was well tolerated and when it occurred, the right ventricular size had increased and the circulation was no longer duct-dependent. In patients who required subsequent surgical corrective treatment, stenting of the duct allowed the definite corrective operation to be performed as the first surgical procedure. During the follow-up period, ranging between 2 months and 2 years, mean 8.7 months increased growth of the pulmonary arteries was seen in all the patients. No distortion of the branch pulmonary arteries was seen.

CONCLUSION

In patients with cyanotic congenital heart disease stenting of the arterial duct is an effective alternative to surgical aorto-pulmonary shunts.

Fontan modification for subsequent non-surgical Fontan completion

OBJECTIVE

Establishment of Fontan circulation in complex univentricular hearts often requires several surgical procedures. We developed a procedure which maintains the advantages of a staged approach, however, during the initial surgery additional preparatory measures are performed to allow subsequent non-surgical Fontan completion.

METHODS

The operation is a lateral baffle Fontan procedure. The baffle bears multiple perforations to allow the inferior vena cava blood to drain into the systemic atrium. Total cavopulmonary connection is performed as usual and the cardiac end of the superior vena cava is subtotally banded. Formally the operation establishes a bi-directional Glenn physiology. During subsequent catheter intervention the banding of the superior vena cava is dilated and the holes in the baffle are closed with appropriate devices.

RESULTS

From April 1994 to December 1995, 18 children having at least two risk factors for Fontan operation received the above described operation. Ages ranged from 3 months to 15 years. Ten patients had one or more previous operations. Bypass time ranged from 86 to 128 min and cross clamp time from 14 to 79 min. O2 saturation after discontinuation of cardiopulmonary bypass was 76% (70-81%). The postoperative recovery of all patients was rapid with early extubation (mean 6 h) and discharge to the ward the morning of the first postoperative day. One patient died. No fluid retention as pericardial, pleural or abdominal fluid effusions occurred. At discharge O2 saturation was 77% (75-82%). In thirteen children successful conversion to total cavopulmonary connection with interventional debanding of the superior vena cava and closure of the fenestrations was performed. After a hospital stay of only a couple of days the children were discharged with normal O2 saturation after Fontan completion.

CONCLUSIONS

We suggest that this modification of the staged Fontan procedure reduces the need for surgical interventions by applying balloon angioplasty and occluder technology to this unique subset of patients.

Oxidized LDL damages endothelial cell monolayer and promotes thrombocyte adhesion

The influence of oxidized low density lipoprotein (LDL) on a human endothelial cell monolayer was examined. The resulting contraction of the oxidized LDL-damaged endothelial cells lets intercellular spaces become enlarged and therefore visible via light microscopy. Electron microscopy reveals that the structural damage facilitates thrombocyte adhesion and formation of microthrombi. Oxidized LDL appears to play a pivotal role in initiating and deteriorating thromboembolic complications.

Concomitant pulmonary valve replacement, VSD closure and coronary artery bypass surgery

BACKGROUND AND AIMS OF THE STUDY

Although pulmonary valve stenosis may be treated by percutaneous balloon valvulotomy, surgery is preferred in adult patients with dysplastic valves.

METHODS

Recently a 50-year-old man with isolated, calcific pulmonary stenosis and concomitant coronary artery disease was referred for surgery. Preoperatively, he suffered from dyspnea (NYHA class I-II) and angina pectoris (CCS class I-II). During catheterization a peak-to-peak gradient of 120 mmHg was measured across the pulmonary valve, while angiography revealed two-vessel coronary artery disease.

RESULTS

During surgery, after opening the main pulmonary artery, an unsuspected small ventricular septal defect (VSD) and a severely calcified, altered pulmonary valve were detected. The VSD was closed and the valve replaced with a stentless bioprosthesis; concomitant double coronary artery bypass grafting was performed. The postoperative course was uneventful.

CONCLUSIONS

Adult patients with pulmonary valve stenosis and concomitant coronary artery disease can be treated simultaneously by surgery with excellent results. Replacement devices may be homografts, or as in this patient, a stentless xenograft.

A new distinctive variation of renal arterial vascularization

In addition to the usual renal arteries, a bilateral artery branching from the aorta was found connecting the aorta to both kidneys in an 82 year-old Caucasian man. By creating an additional blood supply to the kidneys this artery may have had an effect on renal perfusion.

Stentless porcine bioprostheses for all types of aortic root pathology

OBJECTIVE

Conventional biological and mechanical prostheses have important limitations with regard to their results concerning thrombosis, hemorrhage and long-term durability. Aortic valve replacement with stentless devices results in superior hemodynamic function because obstructing stents and sewing rims are avoided. In addition, no anticoagulation therapy is needed.

METHODS

From 1 June 1991 until 31 May 1996, 235 patients received aortic valve replacement with stentless aortic porcine bioprostheses. Patients' ages ranged from 24 to 88 years (mean 64 years). In 21.3% of all patients, concomitant procedures were performed. Coronary artery bypass graft (CABG) and mitral valve surgical therapy were the most frequent ones (31 and 12 cases, respectively). Implanted valve sizes ranged from 21 to 29 mm in diameter.

RESULTS

A total of 122 patients received a subcoronary implantation with the lower row performed with interrupted stitches and the upper row with a continuous suture. In 99 cases we performed the inclusion cylinder technique, also with lower interrupted sutures and running upper sutures after adaptation of the coronary ostia into the graft. In the group with small aortic roots, the total root replacement technique (n = 14) was used. Mortality at 30 days was 4.7% (11/235). Echocardiography at discharge postoperatively revealed a mean gradient across the prosthesis of 6 mm Hg. Color Doppler suggested no or trivial regurgitation in 93% of all examined patients and mild regurgitation without clinical symptoms in 7%. Up to now, 98.2% of all discharged patients have been free of valve-related reoperation.

CONCLUSIONS

With implantation of stentless bioprostheses, an improved hemodynamic function will be obtained. Almost every aortic root pathology can be safely treated with any of the techniques described. The short and intermediate results seem to be at least equal to any other prostheses or treatment methods. The long-term performance of these devices is still under investigation.

Ross operation and right ventricular outflow tract reconstruction with stentless xenografts

Traditionally a homograft valve is used as a pulmonary replacement device for the Ross operation. Right ventricular outflow tract reconstruction during aortic valve replacement with an autograft was performed with stentless xenograft valves in nine patients. Hemodynamic performance is satisfying, but, long term evaluation is needed.

Autograft aortic valve replacement with downsized pulmonary allograft for right ventricular outflow tract reconstruction

A three-week-old neonate underwent aortic valve replacement with a pulmonary autograft (Ross procedure). The right ventricular outflow tract was reconstructed with a downsized pulmonary allograft. The surgical technique is presented. Six months after operation the girl is doing well and both the autograft and allograft function are excellent.

Reconstructive vascular surgery in rotationplasty for malignant tumors of the femur

The rotationplasty procedure of the femur, as first described by Borrgreve, is the functional improvement of an abnormally shortened lower limb. In the last 15 years this procedure has been used in its original form and as modification for tumors of the femur and proximal tibia. The reconstruction of the femoral vessels as an important part of the operation has not enough been accentuated. Principally two types of reconstructions can be performed: the vessels are dissected in the adductor canal or a segmental resection and reanastomosis are performed. Between January 1990 and April 1993 classical and modified rotationplasties were performed for malignant tumors in 34 patients in our institution. In all cases a segmental femoral vessel resection with end-to-end anastomosis were performed. No intra- and postoperative vascular related complications occurred. The authors emphasize the advantage of this method: reanastomosing resected femoral vessels by experienced vascular surgeons is a save, time-saving method. In addition, the radicality of the operation increases in order to obtain excellent long term results.

Technique of aortic valve replacement with the Edwards stentless aortic bioprosthesis 2500

Aortic valve replacement with a stentless device ought to result in superior hemodynamic function, because obstructing stents and sewing rims are eliminated. From 15 June 1991 to 15 October 1991, 15 patients underwent aortic valve replacement with the newly designed Edwards stentless aortic bioprosthesis 2500. Patients' ages ranged from 51 to 70 years (mean 61 years). Preoperatively 4 patients presented with aortic regurgitation, 7 with aortic stenosis and 4 with combined lesions; 7 patients were male and 8 female. No additional cardiac or noncardiac diseases were encountered. The operations were performed under normothermic extracorporeal cardiopulmonary bypass and cold cardioplegic cardiac arrest. The implanted valves ranged from 21 mm to 27 mm in diameter. Ten patients received a subcoronary implantation with the lower row of stitches made up of interrupted sutures and the upper row of a continuous suture. In 5 patients the so-called miniroot technique was used, also with lower interrupted sutures and running upper sutures, after adaptation of coronary ostia to the performed openings in the graft. Aortic cross-clamp time ranged between 73 min and 94 min (mean 82 min). There was no operative mortality or morbidity. Postoperative echocardiography showed no signs of aortic valve regurgation in any patient and continuous wave-Doppler measurements showed that resting pressure gradients across the aortic valve were absent or low. Our preliminary experiences with a stentless aortic xenograft valve show that in presence of an increased cross-clamp time an improved hemodynamic function will be obtained. Further studies will be needed, however, to establish the long-term behavior of this device.