Innominate to contralateral brachial artery bypass via ministernotomy with anatomic tunneling for critical ischemia of the left upper extremity

OBJECTIVES

Scarring from prior bypass surgery and irradiation may compromise revascularization options in critical ischemia due to underlying occlusive disease. Occlusive disease of the axillo-brachial artery is particularly difficult to revascularize under such hostile conditions.

METHOD

We present a case of a 58-year-old woman presenting with a painful, pulseless, and cool left upper extremity. The patient had a known history of left upper extremity occlusive disease which was managed by subclavian-axillary artery stenting with re-occlusion and subsequent extra-anatomic left carotid-to-proximal brachial artery prosthetic bypass, which was complicated by stroke. The patient had a history of left mastectomy, axillary node dissection, and external beam radiation therapy. When considering revascularization options, the combination of post-radiation changes and scarring of the conventional operative zones for revascularization posed a high risk for complications. We describe a novel approach for such revascularization, where the inflow source was the terminal brachiocephalic artery, outflow to the upper left brachial artery, with anatomic intrathoracic-to-axillary tunneling through the thoracic outlet after verifying the lack of dynamic extrinsic compression at that level.

RESULT

The procedure resulted in resolution of the symptoms and the patient continued to do well 2 years later.

CONCLUSION

This case shows that anatomic tunneling through the thoracic outlet can be a viable option for upper extremity revascularization when hostile conditions preclude other anatomic tunneling routes or extra-anatomic options.

Increased Inlet Blood Flow Velocity Predicts Low Wall Shear Stress in the Cephalic Arch of Patients with Brachiocephalic Fistula Access

Background

An autogenous arteriovenous fistula is the optimal vascular access for hemodialysis. In the case of brachiocephalic fistula, cephalic arch stenosis commonly develops leading to access failure. We have hypothesized that a contribution to fistula failure is low wall shear stress resulting from post-fistula creation hemodynamic changes that occur in the cephalic arch.

Methods

Twenty-two subjects with advanced renal failure had brachiocephalic fistulae placed. The following procedures were performed at mapping (pre-operative) and at fistula maturation (8–32 weeks post-operative): venogram, Doppler to measure venous blood flow velocity, and whole blood viscosity. Geometric and computational modeling was performed to determine wall shear stress and other geometric parameters. The relationship between hemodynamic parameters and clinical findings was examined using univariate analysis and linear regression.

Results

The percent low wall shear stress was linearly related to the increase in blood flow velocity (p < 0.01). This relationship was more significant in non-diabetic patients (p < 0.01) than diabetic patients. The change in global measures of arch curvature and asymmetry also evolve with time to maturation (p < 0.05).

Conclusions

The curvature and hemodynamic changes during fistula maturation increase the percentage of low wall shear stress regions within the cephalic arch. Low wall shear stress may contribute to subsequent neointimal hyperplasia and resultant cephalic arch stenosis. If this hypothesis remains tenable with further studies, ways of protecting the arch through control of blood flow velocity may need to be developed.

Altered dependence of aortic pulse wave velocity on transmural pressure in hypertension revealing structural change in the aortic wall

Aortic pulse wave velocity (aPWV), a major prognostic indicator of cardiovascular events, may be augmented in hypertension as a result of the aorta being stretched by a higher distending blood pressure or by a structural change. We used a novel technique to modulate intrathoracic pressure and thus aortic transmural pressure (TMP) to examine the variation of intrathoracic aPWV with TMP in hypertensive (n=20; mean±SD age, 52.1±15.3 years; blood pressure, 159.6±21.2/92.0±15.9 mm Hg) and normotensive (n=20; age, 55.5±11.1 years; blood pressure, 124.5±11.9/72.6±9.1 mm Hg) subjects. aPWV was measured using dual Doppler probes to insonate the right brachiocephalic artery and aorta at the level of the diaphragm. Resting aPWV was greater in hypertensive compared with normotensive subjects (897±50 cm/s versus 784±43 cm/s; P<0.05). aPWV was equal in hypertensive and normotensive subjects when measured at a TMP of 96 mm Hg. However, dependence of aPWV on TMP in normotensive subjects was greater than that in hypertensive subjects (9.6±1.6 versus 3.8±0.7 cm/s per mm Hg increase in TMP, respectively, means±SEM; P<0.01). This experimental behavior was best explained by a theoretical model incorporating strain-induced recruitment of stiffer fibers in normotensive subjects and fully recruited stiffer fibers in hypertensive subjects. These results explain previous contradictory findings with respect to isobaric aPWV in hypertensive compared with normotensive subjects. They suggest that hypertension is associated with a profound change in aortic wall mechanical properties possibly because of destruction of elastin leading to less strain-induced stiffening and predisposition to aortic dissection.

Axillary and innominate artery cannulation during surgery of the thoracic aorta: a comparative study

AIM

The aim of this paper was to compare hospital outcomes in patients undergoing elective surgery of the thoracic aorta using the right axillary artery (RAA) and the innominate artery (IA) as a cannulation site for cardiopulmonary bypass (CPB) arterial inflow.

METHODS

Between September 2009 and October 2011, 71 patients underwent elective aortic procedures with RAA (N.=27) and IA (N.=44) cannulation. Selection of RAA vs. IA was not randomized, but rather based on surgical judgment of best indication in each patient. Pre-, intra-, and postoperative variables were compared according to cannulation site.

RESULTS

Preoperative comorbidities, underlying aortic pathology, and surgical procedures were similar in RAA and IA patients. Hospital mortality was 11.1% and 6.8% in RAA and IA patients, respectively (P=0.243). Overall, 4 brain infarctions occurred, all left sided (RAA: 3.7% vs. IA: 6.8%; P=0.508). One brachial plexus injury, and 1 arterial dissection occurred in RAA group. No cannulation-related morbidity was observed in IA patients. Theoretical CPB flow could be reached in all patients, but resistances through the cannulation sites were more favourable in IA patients.

CONCLUSION

RAA and IA were associated with similarly valid results. The choice between the two, based on the specific patient's characteristics, can improve outcomes after aortic surgery.

[Hemodynamic mechanisms of the superior and inferior vena cava flow changes following experimental myocardial ischemia]

In acute experiments in anesthetized cats myocardial left ventricular ischemia caused the decreasing of the arterial pressure, cardiac output, superior and inferior vena cava flow and venous return. The diminishing of the superior vena cava flow was caused by the decreasing of the cardiac output, increasing of the vascular resistance and decreasing of the blood flow in the region of the brachiocephalica artery. The inferior vena cava flow decreased following the diminishing of the cardiac output and abdominal aorta blood flow, while vascular resistance in this region did not change. In acute experiments in anesthetized rabbits following myocardial ischemia after the blockade of N-cholinoreceptors the superior and inferior vena cava flow decreased in the same level as in control animals. Following myocardial ischemia after the blockade of α-adrenoreceptors the superior and inferior vena cava flow decreased more significant, than in control animals.

[Remote results of surgical reconstruction of the aortic arch in patients with proximal aortic dissection]

INTRODUCTION

It is generally known that Stanford type A aortic dissection has up to now been a serious problem of cardiothoracic surgery. The current state of the art of aortic surgery, anaesthesiological support, and perfusion strategy make it possible to achieve acceptable results in the early postoperative period in various-difficulty aortic arch reconstruction. Taking into consideration that the pathological process to some extent involves the brachiocephalic arteries, of special interest are remote results of various in aggressiveness and radicality types of reconstruction of the aortic arch in its proximal dissection from the point of view of the development of delayed impairments of cerebral circulation.

MATERIAL AND METHODS

Over the period from 1999 to 2011, specialists of the Novosibirsk Scientific Research Institute for Circulatory Pathology named after Academician E.N. Meshalkin under the Ministry of Public Health and Social Development operated on a total of 124 patients presenting with DeBakey type I aortic dissection. All factors supposedly influencing the development of cerebral ischaemia were subdivided into the qualitative and quantitative ones. The qualitative factors included gender, aetiology, type of dissection, type of aortic arch reconstruction, type of cerebral perfusion, type of intervention on the aortic root, previous operations on the heart, and the presence of accompanying CAD, arterial hypertension, chronic obstructive pulmonary diseases, and renal pathology. The quantitative factors were as follows: age, height, body weight, duration of assisted circulation (AC), duration of aortic occlusion (AO), duration of circulatory arrest (CA). We examined a total of 80 patients within the terms of 11-124 months (mean 48,3±26,0 months) after surgical treatment. We studied interrelationship between the factors and the development of cerebral circulation impairments in the remote postoperative period.

CONCLUSION

In the remote postoperative period virtually all cases of focal impairments of cerebral circulation were associated with accompanying atherosclerosis, i. e. the already compromised brachiocephalic vascular bed. Amongst the qualitative parameters the most significant variables were: aetiology, accompanying diseases, and the type of cerebral perfusion.

[Surgical therapeutic decision-making in elderly patients with heart valvular defects combined with lesions of coronary and brachiocephalic arteries]

Due to considerable incidence of combined cardiac and vascular pathology in elderly and aged patients with heart valve defects, of special importance is the problem regarding surgical therapeutic decision-making. The present article is aimed at considering the problems concerning possibility and feasibility of stagewise or simultaneous surgical correction in patients diagnosed as having cardiac valve defect and haemodynamically significant lesions of coronary and/or brachiocephalic arteries based on generalizing the results of international studies.

[The place of vascular surgery in treatment of diabetic patients]

This article is dedicated to diagnostics, prevention and surgical treatment of vascular complications of diabetes mellitus, particularly prevention of ischemic strokes and treatment of critical ischemia of lower limbs. The main tendency in treatment of brachiocephalic artery lesions nowadays is a surgical intervention in the latent stage of the disease. X-ray endovascular surgical techniques are being increasingly used to treat lesions of lower limbs arteries. Limb preservation is impossible without cooperation of many specialists. It's essential to perform careful out-patient follow up of the patient after vascular reconstructive surgery.

[Single-step surgical management of lesions of the ascending aorta and aortic arch, coronary and carotid arteries in a male patient with multifocal atherosclerosis]

Described in the article is a clinical case report concerning single-step surgical management of a male patient presenting with multifocal atherosclerosis accompanied by an aneurysm of the ascending aorta and proximal segment of the aortic arch combined with lesions of the coronary and brachiocephalic vessels, thus showing a possibility of surgical treatment in this cohort of patients, if completely and timely diagnosed. Performing a one-stage operation without aggravating the surgical intervention makes it possible to decrease the risk of complications of both the heart and brain in the intra- and postoperative periods.

[Brain oxygen supply in the residual period of ischemic stroke]

Brain oxygen supply in the residual period of ischemic stroke was studied in 25 patients with systemic atherosclerosis who had ischemic stroke in the basin of the right- or the left middle cerebral artery 1-13 years ago. The diagnosis was verified by multispiral computed tomography. All patients underwent duplex scanning of brachiocephal arteries with the measurement of vessel diameter and blood flow velocity. The venous component of the brain blood flow was evaluated by the data of bifrontal cerebral oxymetry. The greater volume velocity of arterial blood flow and reduced cerebral oxygenation were characteristic of the damaged hemisphere compared to the intact one. The analysis of cerebral vessel reactivity revealed that the index of vasomotor reactivity with the domination of vascular dilatation reserve was higher by 17-18% in the stroke hemisphere. Therefore, the indices of hemodynamics of arteries in the damaged hemisphere were compensatory higher compared to the intact hemisphere but the venous blood flow along the damaged hemisphere was lower due to the vascular dilatation. The asymmetry of vascular tone may be explained by the disturbance of mechanisms of autoregulation of cerebral blood circulation with the hyperfunction of the damaged hemisphere.

[The state of arterial walls in patients with different characeter of atherosclerotic process and latent infection]

Examination of patients differing in manifestation of the atherosclerotic process revealed stable clusters of parameters characterizing the state of arterial walls, presence of infection, immune status, metabolic patterns, and risk factors. Relationship between these variables suggests the dependence of the atherosclerotic process on latent infection, reduced reactivity of the immune system and the action of metabolic factors.

[Peculiarities of atherosclerotic damage of brachiocephalic arteries in patients with type 2 diabetes mellitus]

The state of vascular bed of brachiocephalic arteries was studied by the method of color duplex scanning in 250 patients (116 men and 134 women) with atherosclerosis of various vascular basins which in 62 of them took place at the background of type 2 diabetes mellitus (DM). Two hundred five patients had atherosclerosis of brachiocephalic arteries, 45 patients without atherosclerotic plaques in carotid arteries comprised control group. Mean age of patients was 65.3 +/- 7.6 years. A correlation was revealed between parameters of carotid artery stenosis and age of patients, level of arterial pressure, blood plasma concentration of total cholesterol. Degree of interrelation of these parameters was closer in patients with type 2 DM. Among patients with IHD with class I-III effort angina severity of carotid artery stenoses increased with elevation of functional class of angina. This dependence was most pronounced in patients with type 2 DM. Unstable and calcinated plaques were significantly more frequent in patients with type 2 DM than in patients without DM.

Myocardial thievery: the coronary-subclavian steal syndrome

Coronary-subclavian steal syndrome entails the reversal of blood flow in a previously constructed internal mammary artery coronary conduit, which produces myocardial ischemia. The most frequent cause of the syndrome is atherosclerotic disease in the ipsilateral, proximal subclavian artery. Although coronary-subclavian steal was initially reported to be rare, the increasing documentation of this phenomenon and its potentially catastrophic consequences in recent series suggests that the incidence of the problem has been underreported and that its clinical impact has been underestimated. We review the causes and background of coronary-subclavian steal; methods of preventing, diagnosing, and treating it; and the potential influence of various treatment regimens on long-term survival and the likelihood of late adverse events in patients with coronary-subclavian steal syndrome.

[The specific features of ocular blood flow and brachiocephalic arteries in patients with non-exudative senile macular degeneration]

A hundred and twenty patients (240 eyes) aged 40-65 years (mean age 56.9 +/- 2.1 years) who had non-exudative age-related (AMD) macular degeneration (AMD) were examined. Ultrasound studies, including Doppler color mapping, were conducted to study blood flow in ophthalmic vessels and brachiocephalic arteries. Hemodynamic parameters deteriorated in all patients with non-exudative AMD, which suggests that blood flow deficit in the ophthalmic arterial system, central retinal artery, and posterior ciliary arteries. 88.3% of patients with non-exudative AMD were diagnosed as having brachiocephalic arterial deformities of which bilateral C- and S-shaped pathological tortuosity of carotid and vertebral arteries were most common.

Tracheo-arterial fistula in tracheostomy patients with Duchenne muscular dystrophy

A tracheo-arterial fistula is a serious and life threatening potential complication of a tracheostomy. Since 1984, we experienced nine fatal cases of tracheo-arterial fistula among 60 Duchenne muscular dystrophy (DMD) patients who underwent a tracheostomy. Representative cases included a patient with lordosis (Case 8), in whom the fistula was located in the brachiocephalic artery close to the trachea, and another with severe scoliosis (Case 9), which caused the aorta to compress the trachea. Such anatomical changes can be the cause of a fistula between the trachea and brachiocephalic artery. The anatomical locations between the trachea and brachiocephalic artery are modified by thoracic deformities in DMD patients, and should be confirmed using computed tomography (CT) prior to a tracheostomy procedure. Further, during such a procedure, the tracheal stoma must be placed in a location clearly away from the arteries, and should be followed by regular post-operative examinations using CT and careful management to avoid a tracheo-arterial fistula.

[Treatment of combined lesions of brachiocephalic and lower limb arteries]

Treatment results of 364 patients with multifocal lesions of brachiocephalic and lower limb arteries are analyzed. Indications for surgical treatment were based on priority principle. Staged surgical policy results in 5-year survival of 88-93% patients, improves life quality and saved limbs in 90-93% patients compared with conservative treatment. One-stage surgical interventions are associated with high lethality and should be performed with strong indications only. Conservative treatment cannot be regarded as alternative to surgical procedures.

Endovascular therapies for noncoronary atherosclerosis in the elderly: supra-aortic vessels and thoracoabdominal aorta lesions

Due to the aging of the population and the fact that people are living longer, there are increasing numbers of older patients with noncoronary atherosclerosis. Carotid and subclavian arteries are often the first involved vessels in atherosclerosis, and thoracoabdominal aortic involvement is becoming even more frequent. New techniques, such as intra-arterial thrombolysis, protection and thrombo-aspiration devices, and new stent graft designs are becoming available for percutaneous treatment of atherosclerosis in such vessels. In this review, the authors offer geriatric cardiologists an overview and an update of the most recent advances in techniques and results in the field of interventional treatments of atherosclerosis of supra-aortic vessels and thoracoabdominal aorta in the elderly.

Simplified antegrade cerebral perfusion and myocardial protection during stage I Norwood procedure

Several important modifications have been introduced in the intraoperative management of neonates with hypoplastic left heart syndrome during first-stage palliation. Among these, utilization of selective antegrade cerebral perfusion and interposition of a conduit between the right ventricle and pulmonary artery are currently favored by many centers. We briefly describe our current approach to the modified stage I Norwood procedure.

[Systemic manifestations of rheumatoid arthritis, echostructural changes in brachiocephalic arteries]

AIM

To define echostructural and hemodynamic features of vascular lesions in rheumatoid arthritis (RA) with systemic manifestations.

MATERIAL AND METHODS

Of 125 patients included in the study 70 had RA. They were compared to 40 patients with deforming osteoarthritis (DOA) and 15 patients with atherosclerosis of major cerebral arteries. Extra-articular systemic manifestations were diagnosed in 18 RA (25.7%) patients. Carotid, vertebral arteries and cerebral circulation were studied with ultrasonic duplex scanning on the unit "Vingmed system 5, Norway, 2002".

RESULTS

The study group exhibited a significant reduction of linear perfusion velocity (LPV) with increased vascular resistance indexes in the carotids and vertebral arteries on the right and left. It was more evident in RA patients with systemic manifestations. Scanning carotids in RA with SM patients and RA patients without extra-articular manifestations showed differences suggesting that thickness of intima-media complex was larger when systemic manifestations were present.

CONCLUSION

The revealed changes in circulation may indicate the systemic process.

[Cerebral oximetry in the perioperative evaluation of the reserve of cerebral circulation in patients with brachiocephalic artery lesions]

The reactivity of cerebral vessels and the reserve of collateral compensation of cerebral flow were studied in 71 patients with perioperative carotid stenosis of different degrees. Cerebral oximetry was made at rest and during hypercapnic and compression loads. The method's efficiency was demonstrated for the preoperative evaluation of the cerebrovascular reserve in patients with atherosclerotic affection of vessels in the brachiocephalic stem. A comparison of the preoperative and intraoperative dynamics of rSO2 at compression points at the feasibility of using the cerebral oximetry in predicting the degree of reduced regional oxygenation of the brain in the basin of an intraoperatively pinched artery.

Use of axillary artery to maintain cerebral perfusion in a patient requiring reconstruction of the brachiocephalic trunk and coronary arteries: technical note

Our patient had 80% stenosis of the brachiocephalic artery and total occlusion of the left carotid and left subclavian arteries. Ascending aorta to brachiocephalic artery bypass grafting was performed, with a 10 mm Dacron graft. The right axillary artery was cannulated, and during construction of the distal anastomosis cerebral blood flow was from the right axillary artery. We believe this technique may be beneficial in surgery on an artery in which cerebral blood flow depends exclusively.

Results of vascular reconstructions for a associated lesion of the brachiocephalic arteries and paroxysmal disorders of cardiac rhythm

Annually, about 400,000 new patients with strokes are recorded in Russia. Of these, 80% of patients may develop ischemic brain infarctions. In approximately 30-40% of cases, ischemic lesion of the brain eventuates in lethal outcome; the same number of patients remain heavily disabled and only 15-20% of patients return to the previous level of work fitness. In 30-50% of cases, the development of ischemic stroke and other forms of cerebrovascular insufficiency is caused by stenotic and occlusive lesion of aortic arch branches, being more frequently of atherosclerotic origin. Patients with brachiocephalic artery (BCA) lesion face an important problem of the origin and progression of different forms of cardiac rhythm disorders. In the presence of hemodynamically significant stenotic and occlusive lesion of brain vessels, even transient changes in cardiac rhythm may induce an additional deterioration of cerebral flow. In turn, the origin of arrhythmias in the immediate postoperative period in patients after reconstructions on the BCA is a serious complication which may lead to sudden death. The aim of the present study was to examine the long-term results of the surgical treatment in patients with associated BCA lesion and paroxysmal disorders of cardiac rhythm (PDCR). The treatment results were analyzed in 89 patients aged 35 to 70 years. There were 66 (74.2%) men and 23 (25.8%) women. All the patients had undergone different BCA reconstructions. In the long-term period, this resulted in the lowering of the death rate. Besides, in the long-term period, vascular reconstructions carried out in patients with associated BCA lesion and PDCR not only improved the neurologic status but also favoured the positive course of changes in arrhythmias in 36.4% of patients.

Reversal of pulmonary hypertension after ligation of a brachiocephalic arteriovenous fistula

The arteriovenous (AV) fistula is the access method of choice for long-term hemodialysis according to DOQI guidelines. Among the recognized complications of upper extremity AV fistulae fashioned for hemodialysis are infection, aneurysm formation, and high-output left ventricular failure. We describe a novel cardiopulmonary complication--secondary pulmonary hypertension resulting from an aneurysmal brachiocephalic AV fistula. The clinical presentation, investigation, management, and pathophysiology of this complication are discussed.

[Reactivity of cerebral vessels in occlusive lesions of carotid arteries]

Cerebrovascular CO2 reactivity was examined in 62 patients with occlusive damages of carotid arteries (42 with atherosclerosis, 20 with non-specific aorto-arteritis). Control group consisted of 20 volunteers aged 30-60 years without any signs of cerebrovascular pathology. Increase of blood flow in the middle brain artery during 5-minutes of 5% CO2 inhalation was the main quantitative index which determined autoregulative reaction of cerebral vessels (ARCV). One of the main factors which determined the values of ARCV occurred to be the degree of the damage of carotid arteries. ARCV was not significantly changed in stenosis (up to 80%) as compared to controls. Meanwhile its value was equal to 12 + 4.1 and 13 + 4.2 c/s in stenosis (more than 80%). In other words ARCV permitted to determine hemodynamic significance of the damages of carotid arteries and of brachiocephalic trunk. Cerebrovascular CO2 reactivity permitted to determine either hemodynamic significance of the damages of carotid arteries or collateral reserve capacity of blood vessels. The was quite important for more precise determination of both medical policy and indication of surgical treatment in occlusive damages of carotid arteries.

[Effect of enalapril maleate on vascular endothelial function and platelet-endothelial interactions in patients with essential hypertension]

AIM

Evaluation of endothelial function and platelet-endothelial interactions in patients with essential hypertension and dynamics of these changes in the course of treatment with enalapril maleate.

MATERIALS AND METHODS

The study included 37 patients with essential hypertension and 22 normotensive volunteers. 17 of hypertensive patients received enalapril maleate (enap, KRKA) 5-20 mg/day during the period of 1.5 months. The complex of investigations included: measurement of total plasma cholesteroi, 12-lead ECG, echocardiography, high-resolution ultrasound investigation of brachio-cephalic arteries, evaluation of flow-mediated dilation, measurement of von Willebrand's factor, spontaneous and induced platelet aggregation.

RESULTS

Patients with essential hypertension exhibited higher levels of von Willebrand's factor in plasma and degree of spontaneous and induced platelet aggregation as well as lower responses of vessel wall to hemodynamic stimuli compared to normotensive healthy individuals. There was a strong correlation between endothelial function markers and CAD risk factors, elevation of platelet activity. Treatment with enalapril maleate led to a statistically significant decrease of von Willebrand's factor in plasma and ex vivo platelet aggregation whereas flow-mediated dilatation increased. Values of endothelial function markers and platelet activity approached to those of normotensive subjects and these changes were accompanied by a decrease of ECG signs of left ventricular hypertrophy.

CONCLUSION

Patients with essential hypertension were found to have compromised endothelial function. However, the degree of endothelial dysfunction depends not on hemodynamic parameters, but on the cumulative effect of CAD risk factors. Treatment with enalapril maleate may lead to normalisation of endothelial function and decrease of platelet activity.

Surgical and endovascular treatment of stenosis of the innominate artery

BACKGROUND

Atherosclerotic lesions of the brachiocepfialic trunk are relatively rare compared with other types of vascular diseases. Median sternotomy with direct endothoracic repair is recommended because of good early and long-term results. Nevertheless, this procedure is not without risks such as hemorrhaging, embolism, aortic dissection, infection or death.

METHODS

This report therefore, describes our experience in intraoperative balloon angioplasty and additional stent placement of isolated stenosis of the brachiocephalic trunk with cerebral protection ensured by common carotid artery clamping. Through an anterolateral cervical approach the right common carotid artery was surgically exposed. After dilating the brachiocephalic trunk and positioning the stent, the vessel was repaired with a continuous suture.

RESULTS

In all patients the dilation of the stenosis of the brachiocephalic trunk and the stent placement were successful without any side-effects. No distal embolism with neurologic events, innominate artery dissection, rupture, occlusion or neck hematoma occurred. All patients were discharged three days after the intervention.

CONCLUSIONS

This technique offers a safe, effective approach to stenoses of innominate arteries because it is less invasive than conventional transthoracic or extrathoracic surgery and offers excellent early and mid-term results. We believe that this technique is a safe and effective alternative to conventional surgery.

[Assessing the effect of prosthesis of the brachiocephalic trunk]

The early and long-term results of truncus brachiocephalicus prosthetics in its atherosclerotic occlusions are analysed. EEG mapping, radioisotopic examination of cerebral circulation before and after surgery, clinical examination were performed for evaluation of effectiveness and safety of surgery. The rate of mortality was 6.6%. The technical recommendations are provided. All the patients, who were discharged after surgery, are alive for 2.6 +/- 0.3 years. No cases of recurrence of cerebral circulation disorders were observed. In 100% cases the grafts were patent.

Left innominate vein compression by a brachiocephalic artery anomaly

An unique case of left innominate vein compression by a leftward origin of a brachiocephalic artery in conjunction with an aberrant right subclavian artery anomaly occurred in a young patient. Aortography and magnetic resonance imaging were invaluable in arriving at a diagnosis.

Innominate artery enlargement in congenital arteriovenous fistula with subsequent tracheal compression and stridor

To demonstrate that airway obstruction may be the first manifestation of a congenital fistula, a female newborn is reported who presented with increasing stridor during her first 23 months of life. Magnetic resonance imaging and Doppler echocardiography revealed an enlarged innominate artery with turbulent flow. Angiography demonstrated an arteriovenous fistula between the right subclavian artery and right subclavian vein and an abnormal origin of the right internal thoracic artery. Bronchoscopy showed a pulsating compression of the middle section of the trachea. Closure and division of the fistula and aortotruncopexy were performed. The stridor disappeared, and there was marked relief of the tracheal obstruction, confirmed by bronchoscopy. It is concluded that, a search for enlarged vessels is necessary in cases of airway obstruction.

[The possibilities for the transcranial monitoring of the blood flow in the circle of Willis arteries during operations on the brachiocephalic arteries and in heart operations]

The paper gives the results of arterial blood flow monitoring in the circle of Willis via transcranial Doppler during 81 reparative operations on brachiocephalic arteries (including carotid endarterectomy from the internal carotid artery in 32 patients). Transcranial monitoring of blood flow supports the fact that there is a collateral reflow along the cerebral arteries during removal of the common carotid artery and that there is a relationship between the status of great arteries and arteries of Willis' circle. The paper also summaries the results of a comprehensive ultrasound study of 9 patients who have undergone reparative and plastic operations on the cardiac valves during extracorporeal circulation and general hypothermia. Blood flow was intraoperatively monitored in the arteries of the basis cerebri by using transcranial duplex scanning with colour Doppler flow mapping to evaluate not only hemodynamics, but also the embolic situation, as well as to check up how air was removed from the cardiac cavities by transesophageal echocardiography.

Atherosclerotic innominate artery occlusive disease: early and long-term results of surgical reconstruction

PURPOSE

Few articles have dealt specifically with surgical management of innominate artery (IA) atherosclerotic occlusive disease. We herein present our early and long-term results in a large series of patients.

METHODS

During a 20-year period (1974 to 1993) we operated on 148 patients with IA atherosclerotic occlusive disease. The mean age was 55.8 +/- 9.4 years. Approach was through a median sternotomy in 135 (91%) patients. Endarterectomy was performed in 32 (22%) patients, whereas 116 (78%) patients underwent bypass.

RESULTS

Eight (5.4%) patients died in the perioperative period (four of heart-related causes, two of hemorrhage, one each of pulmonary infection and multiorgan failure). There were five (3.4%) perioperative strokes (three ipsilateral, two contralateral) and three (2.0%) ipsilateral perioperative transient ischemic attacks. Ten (7%) patients were lost to follow-up. Mean follow-up was 77 (2 to 193) months. Thirty-three (24%) patients were monitored 10 or more years. There were 45 (35%) late deaths (19 from cardiovascular-related causes, 15 from cancer, 7 from other known causes, and 4 from unknown causes). Although 11 (8.5%) patients had late neurologic events, only one late stroke occurred in the contralateral hemisphere and no ipsilateral late strokes occurred. Sixteen (11%) patients had late myocardial infarctions, nine of which were lethal. Life-table analysis and perioperative events were used to calculate the probability of survival, which was 77.5% +/- 9.5% and 51.9% +/- 20.8% at 5 and 10 years, respectively, with a 4.4% annual mortality rate. The overall probability of freedom from any neurologic/ocular event was 88.8% +/- 6.2% and 80.4% +/- 11.9% at 5 and 10 years, respectively, with a 1.6% annual occurrence rate. The probability of freedom from ipsilateral neurologic/ocular event was 92.7% +/- 4.8% and 84.0% +/- 11.2% at 5 and 10 years, respectively, with a 1.4% annual occurrence rate. The probability of freedom from ipsilateral stroke was 98.6% +/- 1.9% at 5 and 10 years. The primary patency rate was 98.4% +/- 2.1% and 96.3% +/- 4.7% at 5 and 10 years, respectively. The probability of freedom from reoperation was 95.6% +/- 3.9% and 93.5% +/- 5.9% at 5 and 10 years, respectively.

CONCLUSIONS

Surgical reconstruction of IA atherosclerotic occlusive disease yields acceptable rates of perioperative complications and late mortality and excellent long-term patency and freedom from neurologic events and reoperation.

Partial brachiocephalic perfusion in aortic arch replacement

Eleven patients who underwent replacement of the aortic arch or adjacent areas for aneurysmal disease between 1989 and 1991, using hypothermic cardiopulmonary bypass at 20 degrees to 23 degrees C with partial brachiocephalic perfusion, were studied. Selective perfusion of the innominate artery was performed in all 11 patients through the right axillary artery, while partial brachiocephalic perfusion was carried out using a separate arterial roller pump with a perfusion flow rate of 10 ml/kg per min. Direct cannulation to the left common carotid and left subclavian artery was not performed in this method. There were 4 men and 7 women who ranged in age from 26 to 78 years, with a mean age of 56 years. The etiology of aneurysmal disease was aortic dissection in 10 patients, and aortitis syndrome in 1. The cardiopulmonary bypass time was 214.3 +/- 39.3 min, aortic cross-clamp time 131.5 +/- 33.4 min, and partial brachiocephalic perfusion time 57.6 +/- 15.1 min. There were three operative deaths (27.3%), the causes being multiple organ failure, acute peritonitis, and infection of the composite graft in the ascending aorta, in one patient each, respectively. However, there were no deaths related to the technique of partial brachiocephalic perfusion and no neurological complications were seen in this series. Thus, we believe that partial brachiocephalic perfusion under hypothermic cardiopulmonary bypass is safe and effective in surgery for aortic aneurysms involving the aortic arch.

[Aortic flow patterns in normal neonates with patent ductus arteriosus: evaluation by Doppler color flow imaging]

Serial Doppler echocardiography was performed in 12 normal neonates (0.5-4.0 hrs after birth) to evaluate flow patterns through the ductus arteriosus, and in the aorta and brachiocephalic artery. At the initial examination, flow through the ductus arteriosus was bidirectional in eight of the 12 neonates and continuously left-to-right in the remaining four. The bidirectional ductal shunts became continuous left-to-right flows within 11-21 hrs after birth in seven of the eight neonates and resolved by 29-47 hrs after birth. In the remaining four neonates, the continuous left-to-right shunts disappeared 14-36 hrs after birth. Systolic ejection flow patterns in the aorta and brachiocephalic artery had a triangular shape with the peak velocity in early systole, followed by a minimal flow reversal in all sites examined. Diastolic flow patterns in each arterial site were as follows: 1. In the ascending aorta, there was slow and sustained diastolic forward flow, which did not change with increasing age. 2. In the brachiocephalic artery, there was a pan-diastolic flow reversal in the neonates with bidirectional ductal flow (7/8). This pattern changed to slow pan-diastolic forward flow when the ductal changed to continuous left-to-right flow or when the ductal closure was confirmed. Most (3/4) of the remaining four neonates with continuous left-to-right ductal flow exhibited pan-diastolic forward flow. Another showed a pan-diastolic flow reversal 2 hrs after birth, which changed to pan-diastolic forward flow in the second examination 6 hrs after birth. 3. In the distal aortic arch, there was a pan-diastolic forward flow in all the neonates, and the velocity decreased when a closure of the ductus was confirmed. 4. In the descending aorta, there was a pan-diastolic flow reversal in neonates with bidirectional ductal flow (7/8). This reversal changed to pan-diastolic forward flow, when the ductal flow changed to continuous left-to-right flow or when the ductal closure was confirmed. In the remaining four neonates with continuous left-to-right ductal flow, two showed a pan-diastolic flow reversal at the initial examinations 2 to 3 hrs after birth. This became a pan-diastolic forward flow at the second examinations 6 and 12 hrs after birth. In the other two, there was a pan-diastolic forward flow which did not change. This pan-diastolic flow reversal observed in the brachiocephalic artery and descending aorta was closely related to the bidirectional ductal flow.(ABSTRACT TRUNCATED AT 400 WORDS)

[Cerebral blood flow rate during cardiopulmonary bypass and optimal cerebral perfusion flow rate during separated brain perfusion--a clinical study]

There is no established theory to determine the cerebral blood flow rate (CBF) during not only the standard cardiopulmonary bypass but during the cardiopulmonary bypass with separated brain perfusion. This study was carried out to answer the following questions. (1) what is the relationship during the cardiopulmonary bypass between CBF and systemic flow rate or blood pressure?. (2) what is the optimal flow rate to the innominate artery during the separated brain perfusion? Twenty-one patients were selected for this study, who were operated under the cardiopulmonary bypass with a standard roller pump and a membrane oxygenator under moderate hypothermia (nasopharyngeal temperature of 26-28 degrees C). Systemic flow rate was maintained between 40 and 70 ml/kg/min. CBF before the cardiopulmonary bypass was 30.6 +/- 5.5 ml/100 g brain/min, and increased to 33.8 +/- 8.9 ml/100 g brain/min during the cardiopulmonary bypass. CBF was proportional to systemic flow rate (r = 0.62, p less than 0.01) and showed poor association with blood pressure ranged from 35 to 94 mmHg. As for the relationship between innominate arterial and cerebral blood flow rate, CBF linearly followed the decrease of innominate arterial flow rate to below about 9 ml/kg/min, but showed almost no changes when innominate arterial flow rate was over 9 ml/kg/min. It was observed that cerebral oxygen consumption did not decrease significantly under moderate hypothermia (26-28 degrees C), as far as CBF of 25 ml/100 g brain/min was maintained. Based on the relationship between innominate arterial and cerebral blood flow rate, it was shown that the innominate arterial flow rate to provide CBF of 25 ml/100 g brain/min was 5.5 ml/kg/min.(ABSTRACT TRUNCATED AT 250 WORDS)

Pulsed Doppler assessment of innominate artery obstructive diseases

In 14 patients with severe stenosis or occlusion of the innominate artery a new high-energy, low-frequency (2 MHz) pulsed Doppler ultrasound method was used to investigate blood flow velocity patterns of both intrathoracic and intracranial cerebral arteries. Direct acquisition and evaluation of the innominate artery at its origin near the aortic arch enabled separation of it from adjacent arteries and reliable differentiation of stenosis from occlusion. Transcranial recordings from the basal cerebral arteries showed abnormal Doppler signals in 12 patients (86%). Among these abnormalities, observation of a latent steal phenomenon was closely related to the prevalence of cerebrovascular events. This latent steal phenomenon was characterized by a transient reduction of orthograde blood flow in the ipsilateral anterior, middle, and posterior cerebral arteries or in the basilar artery during postischemic hyperemia of the upper extremities. The predictive value of the latent steal phenomenon for the management and follow-up of asymptomatic patients with severe innominate artery obstructions is discussed.

[Non-invasive methods of examination in the diagnosis of hemodynamic phenomena of "borrowing" and "stealing" of blood]

Hemodynamic borrowing and stealing phenomena in various vascular basins have been detected and quantified, using ultrasonic dopplerography and transcutaneous oxygen tension measurement, in 74 patients. The results were confirmed by aorto-arteriography. These noninvasive procedures are shown to be highly valuable for the diagnosis of blood borrowing and stealing.

A biophysical and histological analysis of factors that lead to aortic rupture in normal and lathyritic turkeys

These experiments were designed to determine if local differences in elastic properties or wall structure contributed to the development of aortic rupture in turkeys. Static elastic properties were measured from pressure-volume curves of cylindrical segments of upper and lower thoracic aorta and innominate artery in two groups of lathyritic birds and two age-matched control groups. The biggest changes were in the young lathyritic group that was on 0.04% beta-aminoproprionitrile at 3 weeks of age and continued for 2, 3, or 4 weeks. Much smaller changes were seen in the older group that started on 0.05% beta-aminoproprionitrile at 6 weeks of age for 10 days and then 0.02% beta-aminoproprionitrile for the next 9-12 weeks. The biggest changes were seen in the abdominal aorta, which ruptured spontaneously in 50% of the young lathyritic group. The birds had a marked decrease in the number of elastin layers per unit wall thickness. Analysis of the elastic diagrams showed that the elastance of both elastin and collagen were altered in the young lathyritic group. Rupture appeared to follow partial dissection of plaques, but true longitudinal dissection did not occur.

Steady flow visualization in a rigid canine aortic cast

Steady flow studies were conducted in a transparent canine aortic cast. The cast segment stretched from the aortic valve to beyond the renal arteries and included all major branches. Flow was visualized by analysis of dye streaklines. Flow rates for basal and exercising cardiovascular states were simulated. The Reynolds numbers in the ascending aorta for basal and exercising conditions were 900 and 1587 respectively. Aortic core flow was laminar in basal simulations. Disturbed flow commenced in the upper descending aorta with exercising flow rates. Separation zones existed along the inner curvature of the aortic arch and the proximal walls of the brachiocephalic, left subclavian, and coeliac arteries. Such zones may exist over a portion of the cardiac cycle. If either renal artery was occluded, then a vortex formed. This vortex is associated with high shear regions which correlate well with sites where sudanophilic lesions have been reported in cholesterol-fed nephrectomized rabbits.

[Cerebrovascular Doppler studies--a potent tool in neuroangiology]

Cerebrovascular disease is caused in about half of the patients by obstructions in the extracranial cerebral arteries. In the other half, stroke is due in roughly equal proportions to obstructive intracranial arterial lesions, emboli from the heart, or intracranial hemorrhage. Half of the patients with major ischemic stroke had previous warning signs in the form of transient ischemic attacks (TIA), reversible ischemic neurologic deficit (RIND) or infarction with only minor residual deficit not limiting daily activity, professional skills, and quality of life. Investigation of patients with warning signs of impending ischemic stroke is mandatory in order to prevent other events with possible major disability, but also, in patients with acute infarction, in order to choose the appropriate early therapy and rehabilitation. Routine cerebrovascular Doppler examination based on continuous-wave equipment has been successfully used to detect extracranial arterial obstructions. In the authors' experience of more than 12000 patients this noninvasive diagnostic tool makes it possible-in conjunction with the patient's history and the results of the clinical examination-to differentiate between obstructions needing surgery and lesions small enough to warrant medical treatment. Minor lesions which do not disturb blood flow locally, or accessible to available continuous-wave Doppler equipment, can be detected with real-time ultrasound imaging systems, i.e. B-mode or B-mode-Doppler-(duplex) systems in addition to routine Doppler examination. These complex systems also serve to follow-up patients with minor lesions which are not treated, or treated medically, in regard to deterioration, possible invariability, or even regression of a lesion.

Cortical ischemia: effect upon direct cortical response

Correlation of cortical blood flow as measured by a thermal diffusion flow probe (CBFp) with the direct cortical response (DCR) was studied in 48 lightly anesthetized cats with global ischemia. Thresholds for attenuation and loss of DCR were 21.3 +/- 4.7 and 8.7 and 3.4 ml/100 g/min respectively. In abrupt ischemia, CBFp of 0-3 ml/100 g/min produced absence of DCR in 6 min or less; however, at CBFp of 5-10 ml/100 g/min, the time to obliteration of DCR varied from 5 to 180 min. DCR was unlikely to recover after 13 min of 0-2 ml/100 g/min and after 35 min of 4-5 ml/100 g/min. At higher flows, DCR could recover over 60 min or more of ischemia. With gradual production of ischemia, flows less than 20 ml/100 g/min for over 60 min had a detrimental effect upon recovery of DCR if DCR was lost for 7.5 min or more. Some evidence that implied adaptability of the cortex to ischemia was found.

[Reliability and limitations of Doppler sonography of the cranial arteries ]

High-grade stenoses and occlusions of the internal carotid artery can be detected and differentiated with high accuracy by Doppler sonography. The hemodynamic effect of obliterations of the subclavian and innominate artery on cerebral blood flow readily can be examined too. With lower-grade stenoses of the supraaortic arteries, there are some limitations in accuracy which are discussed in detail. In some cases, Doppler sonography can replace angiography, but it still must be considered, that this method depends greatly on experience.