The implication of vasa vasorum in surgical diseases of the aorta

Vasa vasorum (VV) are microscopic vases that perfuse the vessel's wall; arteries and veins. Many recent researches support the opinion that VV have a significant role in aortic pathology. The VV, or 'the vessels of the vessels', form a network of microvessels that lie in the adventitia and penetrate the outer media of the host vessel wall. Although the importance of the VV in providing nutritional support is not well known, obstruction of blood flow through these vessels has been implicated in the pathogenesis of many cardiovascular diseases such as aortic intramural hematoma, aortic aneurysm, and acute or chronic aortic dissection. Although the proliferation of VV due to atherogenic stimuli is controversial, experimental and clinical studies strongly suggest the potential of VV in vascular proliferative disorders. It seems that the rupture of VV is implicated in intramural hematoma, which can develop in acute aortic dissection. In this review article, we would like to stress the anatomy and mainly the pathophysiology, and the implication of VV in the acute and chronic aortic pathologies.

Postoperative peri-axillary seroma following axillary artery cannulation for surgical treatment of acute type A aortic dissection

The arterial cannulation site for optimal tissue perfusion and cerebral protection during cardiopulmonary bypass (CPB) for surgical treatment of acute type A aortic dissection remains controversial. Right axillary artery cannulation confers significant advantages, because it provides antegrade arterial perfusion during cardiopulmonary bypass, and allows continuous antegrade cerebral perfusion during hypothermic circulatory arrest, thereby minimizing global cerebral ischemia. However, right axillary artery cannulation has been associated with serious complications, including problems with systemic perfusion during cardiopulmonary bypass, problems with postoperative patency of the artery due to stenosis, thrombosis or dissection, and brachial plexus injury. We herein present the case of a 36-year-old Caucasian man with known Marfan syndrome and acute type A aortic dissection, who had direct right axillary artery cannulation for surgery of the ascending aorta. Postoperatively, the patient developed an axillary perigraft seroma. As this complication has, not, to our knowledge, been reported before in cardiothoracic surgery, we describe this unusual complication and discuss conservative and surgical treatment options.

Remnant of a non-patent ductus arteriosus mimicking traumatic thoracic aorta transection: a case report

We present an interesting case of a 53-year-old man with a non-patent ductus arteriosus erroneously diagnosed as acute thoracic aorta transection after a car accident. The aortography revealed a "rupture" of the linear inner curve of the aorta in the isthmus area, as well as a protrusion of the aortic lumen in the corresponding area. During the followed thoracotomy an intact thoracic aorta and the remnant of a non-patent ligamentum arteriosum were found. It is the first reported case and we review all the possible entities which may give a false-positive image of traumatic aortic transection.

"The non-ischemic repair" as a safe alternative method for repair of anterior post-infarction VSD

Patient's myocardium with post-infarction ventricular septum defect (VSD) is characterized by severe dysfunction. The "additive ischemia" caused by the operating process of cross-clamp ischemia and reperfusion injury, has a significant aggravation to the myocardium and overall negative impact to patient's outcome. We present a useful, safe and advantageous methodology in order to abolish "the toxic phase" of ischemia-reperfusion which is adopted by most as the "classic repair method" of myocardial protection. This abolition is in our opinion, particularly beneficial in order to reverse postoperatively the Low Cardiac Output Syndrome (LOS) and achieve better short and long term results. By using this method we avoid the aortic occlusion, the use of systematic hypothermia and any cardioplegic arrest. Furthermore, the total cardio-pulmonary bypass (CPB) time is significantly reduced, tissue debridement and stitching is much easier and safer. We think the method is applicable for every anterior and apical case of post-infarction septum rupture. After application of method in 3 patients with anterior post-myocardial infarction VSD, we are convinced that the patient will have a better postoperative haemodynamic condition and therefore a better outcome.

Strategies to prevent intraoperative lung injury during cardiopulmonary bypass

During open heart surgery the influence of a series of factors such as cardiopulmonary bypass (CPB), hypothermia, operation and anaesthesia, as well as medication and transfusion can cause a diffuse trauma in the lungs. This injury leads mostly to a postoperative interstitial pulmonary oedema and abnormal gas exchange. Substantial improvements in all of the above mentioned factors may lead to a better lung function postoperatively. By avoiding CPB, reducing its time, or by minimizing the extracorporeal surface area with the use of miniaturized circuits of CPB, beneficial effects on lung function are reported. In addition, replacement of circuit surface with biocompatible surfaces like heparin-coated, and material-independent sources of blood activation, a better postoperative lung function is observed. Meticulous myocardial protection by using hypothermia and cardioplegia methods during ischemia and reperfusion remain one of the cornerstones of postoperative lung function. The partial restoration of pulmonary artery perfusion during CPB possibly contributes to prevent pulmonary ischemia and lung dysfunction. Using medication such as corticosteroids and aprotinin, which protect the lungs during CPB, and leukocyte depletion filters for operations expected to exceed 90 minutes in CPB-time appear to be protective against the toxic impact of CPB in the lungs. The newer methods of ultrafiltration used to scavenge pro-inflammatory factors seem to be protective for the lung function. In a similar way, reducing the use of cardiotomy suction device, as well as the contact-time between free blood and pericardium, it is expected that the postoperative lung function will be improved.

Left ventricular diastolic dysfunction of the cardiac surgery patient; a point of view for the cardiac surgeon and cardio-anesthesiologist

BACKGROUND

Left ventricular diastolic dysfunction (DD) is defined as the inability of the ventricle to fill to a normal end-diastolic volume, both during exercise as well as at rest, while left atrial pressure does not exceed 12 mm Hg. We examined the concept of left ventricular diastolic dysfunction in a cardiac surgery setting.

MATERIALS AND METHODS

Literature review was carried out in order to identify the overall experience of an important and highly underestimated issue: the unexpected adverse outcome due to ventricular stiffness, following cardiac surgery.

RESULTS

Although diverse group of patients for cardiac surgery could potentially affected from diastolic dysfunction, there are only few studies looking in to the impact of DD on the postoperative outcome; Trans-thoracic echo-cardiography (TTE) is the main stay for the diagnosis of DD. Intraoperative trans-oesophageal (TOE) adds to the management. Subgroups of DD can be defined with prognostic significance.

CONCLUSION

DD with elevated left ventricular end-diastolic pressure can predispose to increased perioperative mortality and morbidity. Furthermore, DD is often associated with systolic dysfunction, left ventricular hypertrophy or indeed pulmonary hypertension. When the diagnosis of DD is made, peri-operative attention to this group of patients becomes mandatory.

Cardiac surgery in a patient with retroperitoneal fibrosis and heart valvulopathy, both due to pergolide medication for Parkinson's disease

Retroperitoneal fibrosis is best described as a chronic inflammatory process which may be idiopathic, but can rarely be brought about by medications, such as pergolide, used for treating Parkinson's disease. Pergolide can produce a fibrotic process in heart valves, resulting in valve insufficiency in up to 25% of cases. Herein we describe the case of a 68-year-old man who received pergolide for 2 years for Parkinson's disease. The patient developed retroperitoneal fibrosis resulting in renal failure from ureteral obstruction necessitating ureteral stenting, as well as significant aortic and mitral valve insufficiency. He successfully underwent surgery for combined aortic valve, mitral valve and ascending aorta replacement because of severe valve insufficiency and dilated (d = 5.8 cm) ascending aorta. Retroperitoneal fibrosis improved with pergolide cessation and corticosteroid treatment. This is the second case reported in the literature, of a patient who had double valve and ascending aorta replacement surgery because he suffered from this rare but serious adverse effect of dopamine agonists used for managing Parkinson's disease.

Sutureless technique to support anastomosis during thoracic aorta replacement

Background

In aortic replacement procedures the aortic wall and Teflon strips form a double layer, with the use of continuous sutures. Surgical glues may or may not be used to enhance the durability of the anastomoses. In this technical report a modification of the aortic stumps preparation is devised.

The technique reduces substantially the preparation time of the aortic stumps by the use of ligation clips and a surgical sealant.

Technique

Suturing is the standard method for the aortic-teflon double-layer formation prior to Dacron anastomosis. In this study, instead of suturing, 5-6 ligation clips are primarily applied on the exterior of the double layer to facilitate proper cooptation. Secondarily, in order to fuse the two layers together, a sealant is injected in between the Teflon and aortic wall. Thus each stump is delivered quickly sutureless for the Dacron anastomosis.

Between January 2003 and March 2009 this modified operative technique was performed in 14 cases (group A) with a mean age of 50 ± 16 years. This was contrasted against 24 controls (group B), with a mean age of 40 ± 28 years, treated with the conventional method, where only continuous sutures were used during the anastomosis. All patients were cases of ascending aorta replacement and/or aortic hemi-arch replacement, for acute aortic dissection or aortic dilatation.

Results

The pure anastomosis time (stump preparation and Dacron connection) was shortened by approximately 25 minutes depending on surgeon's experience. The anastomosis blood-loss was also significantly reduced in the sutureless group A, as evident by the dry operative field and the limited use of blood products, post-prosthetic graft anastomosis. This reflected to a faster post-operative recovery, faster extubation and fewer complications. At a mean follow-up of 21 ± 7 days, there were no post-operative deaths being related to acute aortic dissection or rupture of the anastomotic site.

Conclusion

Aortic replacement with the combination of ligation clips and a surgical sealant vs. sutures alone allows easy manipulations of the aorta and adaptation of the diameters, thus optimizing aortic operational timings and hemostasis. Moreover, it prevents blood loss and aortic wall trauma from multiple sutures.

Intramural haematoma of the thoracic aorta: who's to be alerted the cardiologist or the cardiac surgeon?

This review article is written so as to present the pathophysiology, the symptomatology and the ways of diagnosis and treatment of a rather rare aortic disease called Intra-Mural Haematoma (IMH). Intramural haematoma is a quite uncommon but potentially lethal aortic disease that can strike as a primary occurrence in hypertensive and atherosclerotic patients to whom there is spontaneous bleeding from vasa vasorum into the aortic wall (media) or less frequently, as the evolution of a penetrating atherosclerotic ulcer (PAU). IMH displays a typical of dissection progress, and could be considered as a precursor of classic aortic dissection. IMH enfeebles the aortic wall and may progress to either outward rupture of the aorta or inward disruption of the intima layer, which ultimately results in aortic dissection. Chest and back acute penetrating pain is the most commonly noticed symptom at patients with IMH. Apart from a transesophageal echocardiography (TEE), a tomographic imaging such as a chest computed tomography (CT), a magnetic resonance (MRI) and most lately a multy detector computed tomography (MDCT) can ensure a quick and accurate diagnosis of IMH. Similar to type A and B aortic dissection, surgery is indicated at patients with type-A IMH, as well as at patients with a persistent and/or recurrent pain. For any other patient (with type-B IMH without an incessant pain and/or without complications), medical treatment is suggested, as applied in the case of aortic dissection. The outcome of IMH in ascending aorta (type A) appears favourable after immediate (emergent or urgent) surgical intervention, but according to international bibliography patients with IMH of the descending aorta (type B) show similar mortality rates to those being subjected to conservative medical or surgical treatment. Endovascular surgery and stent-graft placement is currently indicated in type B IMH.

Endovascular stent: grafting in penetrating atherosclerotic ulcer of the thoracic aorta

The aim of our study is the presentation of some interesting images of a case with symptomatic penetrating atherosclerotic ulcer (PAU) of the thoracic aorta and its endovascular treatment. Penetrating atherosclerotic ulcer is an ulcerating atherosclerotic lesion that penetrates the elastic lamina and is correlated with intramural hematoma (IMH) formation into the media layer of the aortic wall. PAU is more common in the elderly with severe atherosclerosis, hypertension, and hyperlipidemia. Transesophageal echocardiography, computed tomography, and magnetic resonance imaging are the common diagnostic tools. Surgical treatment may become necessary in cases involving the ascending aorta or in cases of intramural haematoma formation. In the era of minimally invasive surgery stent-grafting is indicated mainly in the elderly patients in presence of serious co-morbidities.

Methods of estimation of mitral valve regurgitation for the cardiac surgeon

Mitral valve regurgitation is a relatively common and important heart valve lesion in clinical practice and adequate assessment is fundamental to decision on management, repair or replacement. Disease localised to the posterior mitral valve leaflet or focal involvement of the anterior mitral valve leaflet is most amenable to mitral valve repair, whereas patients with extensive involvement of the anterior leaflet or incomplete closure of the valve are more suitable for valve replacement. Echocardiography is the recognized investigation of choice for heart valve disease evaluation and assessment. However, the technique is depended on operator experience and on patient's hemodynamic profile, and may not always give optimal diagnostic views of mitral valve dysfunction. Cardiac catheterization is related to common complications of an interventional procedure and needs a hemodynamic laboratory. Cardiac magnetic resonance (MRI) seems to be a useful tool which gives details about mitral valve anatomy, precise point of valve damage, as well as the quantity of regurgitation. Finally, despite of its higher cost, cardiac MRI using cine images with optimized spatial and temporal resolution can also resolve mitral valve leaflet structural motion, and can reliably estimate the grade of regurgitation.

A less invasive management of post-thyroidectomy descending necrotizing mediastinitis is feasible: a case report and literature review

BACKGROUND

Descending necrotizing mediastinitis (DNM) is a life-threatening complication secondary to oropharyngeal abscesses, esophageal perforation, or neck infections spreading into the mediastium, but very uncommon after thyroidectomy. Early diagnosis and close clinical and laboratory monitoring are crucial for patient survival. CT scanning of the cervical and thoracic area is a useful tool for diagnosis and follow-up. Different surgical approaches in the management of DNM have been proposed, the most widely accepted being a combined cervicotomy with lateral thoracotomy procedure.

CASE REPORT

A rare case of DNM with group A ss-hemolytic streptococci, in a 47-year-old patient developing after thyroidectomy for multinodular goiter is presented. A more conservative approach through a cervical incision was followed and thoracic drains for pleural effusion evacuation were inserted. After re-operation, repeated CT scanning for disease progression and prompt surgical wound cleaning were performed. Antibiotic therapy was continued up to one month after release. The patient's recovery was uneventful and continues well.

CONCLUSIONS

To the best of the authors' knowledge this is the second case of post-thyroidectomy DNM reported. According to present data it is recommend that a less invasive approach could be satisfactory when prompt diagnosis is established and the thoracic drainage is effective. This case suggests that repeated postoperative CT scanning and close clinical and laboratory monitoring could make an additional thoracotomy a second-line procedure. Moreover, due to the fact that only two cases of post-thyroidectomy DNM are reported worldwide, therapy of this condition remains an open question.