Effects of selective carotid body stimulation with adenosine in conscious humans.

KEY POINTS: In humans, excitation of peripheral chemoreceptors with systemic hypoxia causes hyperventilation, hypertension and tachycardia. However, the contribution of particular chemosensory areas (carotid vs. aortic bodies) to this response is unclear. We showed that selective stimulation of the carotid body by the injection of adenosine into the carotid artery causes a dose-dependent increase in minute ventilation and blood pressure with a concomitant decrease in heart rate in conscious humans. The ventilatory response was abolished and the haemodynamic response was diminished following carotid body ablation. We found that the magnitude of adenosine evoked responses in minute ventilation and blood pressure was analogous to the responses evoked by hypoxia. By contrast, opposing heart rate responses were evoked by adenosine (bradycardia) vs. hypoxia (tachycardia). Intra-carotid adenosine administration may provide a novel method for perioperative assessment of the effectiveness of carotid body ablation, which has been recently proposed as a treatment strategy for sympathetically-mediated diseases. ABSTRACT: Stimulation of peripheral chemoreceptors by acute hypoxia causes an increase in minute ventilation (VI), heart rate (HR) and arterial blood pressure (BP). However, the contribution of particular chemosensory areas, such as carotid (CB) vs. aortic bodies, to this response in humans remains unknown. We performed a blinded, randomized and placebo-controlled study in 11 conscious patients (nine men, two women) undergoing common carotid artery angiography. Doses of adenosine ranging from 4 to 512 µg or placebo solution of a matching volume were administered in randomized order via a diagnostic catheter located in a common carotid artery. Separately, ventilatory and haemodynamic responses to systemic hypoxia were also assessed. Direct excitation of a CB with intra-arterial adenosine increased VI, systolic BP, mean BP and decreased HR. No responses in these variables were seen after injections of placebo. The magnitude of the ventilatory and haemodynamic responses depended on both the dose of adenosine used and on the level of chemosensitivity as determined by the ventilatory response to hypoxia. Percutaneous radiofrequency ablation of the CB abolished the adenosine evoked respiratory response and partially depressed the cardiovascular response in one participant. The results of the present study confirm the excitatory role of purines in CB physiology in humans and suggest that adenosine may be used for selective stimulation and assessment of CB activity. The trial is registered at ClinicalTrials.gov NCT01939912.

Dissociation between blood pressure and heart rate response to hypoxia after bilateral carotid body removal in men with systolic heart failure.

While the ventilatory response to hypoxia is known to be mediated by the carotid bodies, the origin of the haemodynamic alterations evoked by hypoxia is less certain. Bilateral carotid body removal (CBR) performed to treat congestive heart failure may serve as a model to improve our understanding of haemodynamic responses to hypoxia in humans. We studied six congestive heart failure patients before and 1 month after CBR [median (interquartile range): age, 58.5 (56-61) years old; and ejection fraction, 32 (25-34)%]. Peripheral chemosensitivity (hypoxic ventilatory response) was equated to the slope relating lowest oxygen saturation to highest minute ventilation following exposures to hypoxia. Likewise, systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) slopes were calculated as slopes relating the lowest oxygen saturations to the highest SBP, DBP and HR responses. We found that CBR reduces the hypoxic ventilatory response (91%, P < 0.05), SBP (71%, P < 0.05) and DBP slopes (59%, P = 0.07). In contrast, the HR slope remained unchanged. The dissociation between the blood pressure and HR responses after CBR shows involvement of a different chemoreceptive site(s) maintaining the response to acute hypoxia. We conclude that carotid bodies are responsible for ventilatory and blood pressure responses, while the HR response might be mediated by the aortic bodies. The significant reduction of the blood pressure response to hypoxia after CBR suggests a decrease in sympathetic tone, which is of particular clinical relevance in congestive heart failure.

[Modern topical hemostatic agents - a breakthrough in vascular surgery]. / Nowoczesne preparaty o miejscowym dzialaniu hemostatycznym - przelom w chirurgii naczyniowej.

OBJECTIVES: The authors present the impact of the topical hemostatic agents (PerClot®, Fibrillar®, and Surgiflo®) in both primary arterial anastomoses, and anastomoses with synthetic prostheses. MATERIAL AND METHODS: In 2012, in the Department of Vascular Surgery in Wroclaw, the topical hemostatic dressings were successfully applied to 106 patients (Fibrillar® - 65, PerClot® - 26, and Surgiflo® - 15) in case of difficulties to stop bleeding. RESULTS: The topical hemostatic agents appear both to reduce blood loss and to shorten the operation time in 95% of cases. CONCLUSIONS: The decrease both in blood loss and operation time can lead to the patient safety improvement.

Recurrent syncope caused by compression of internal carotid artery by an anomalous hyoid bone.

In rare cases a syncope can be caused by compression or irritation of the carotid artery and the carotid sinus due to congenital anatomical anomalies of cervical structures like the hyoid bone. We present the case a of 36 year old man with recurrent syncopes when turning his head. Clinical investigations revealed a hyoid bone anomaly with elongated lesser cornua, especially on the right symptomatic side. Surgical resection of the right lesser cornu led to complete resolution of symptoms over a two year follow-up. Syncope especially in younger subjects may be caused by congenital anomalies of the musculoskeletal system in the cervical region and should be considered in the differential diagnosis of syncope, transient cerebral ischemia and stroke.

[The comparison of the healing of the classic vascular prostheses and stentgrafts in the abdominal aneursyms]. / Porównanie wgajania syntetycznych protez naczyniowych klasycznych i wewnatrznaczyniowych w tetniakach aorty brzusznej.

THE PURPOSE: Every foreign body injected into an organism causes an inflammatory condition. Among other things leukocytes take part in it. The healing of a vascular prosthesis means gradual subsiding of an inflammatory condition. The process can be monitored with the series of scintigraphy following decrease of an area of concentrating of Technetium-labeled leukocytes. The purpose of work was an appraisal of the healing of both types of prostheses in cases of patients operated because of aneurism of abdominal aorta. MATERIAL AND METHODS: In three years 64 patients have been examined. They were divided into two equal groups: I-patients after (stent-graft) being implanted because of abdominal aneurysm, II-patients after aortobifemoral prosthesis being implanted of the same reason. The scintigraphy was done in 3-4 day, in 3-, 6- and 12 after a surgery. A surface of concentrating of leucocytes was counted in a computer programme which allows manual marking of a contour. The results were put through a statistical processing. RESULTS: During a period after surgery an intensified inflammatory condition has been stated in a group of patients operated in classic way. In both groups a decreasing of an inflammatory condition has been observed. After 12 months an area of concentrating of leucocytes took up to 10 percent of initial values. CONCLUSIONS: The decreasing of an area of concentrating of leucocytes was observed independently of a type of vascular prosthesis. The higher reaction was where the classic prostheses were used. The scintigraphy shows only a cellular part of an inflammatory answer and it cannot be an independent way of a monitoring of the healing of the prostheses.

[The use of the synthetic silver coated prosthesis and penduculated omentum flap in the treatment of prostheses infection]. / Zastosowanie syntetycznej protezy impregnowanej solami srebra i plata sieci wiekszej w leczeniu zakazen protez naczyniowych.

There is a methods of surgical treatment of secondary enteroaortal fistula after infection of vascular prostheses with the use silver prosthesis and great omentum. Secondary enteroaortal fistula is the most serious complication followed infection of vascular prosthesis, with high risk of death rate regardless of different operative methods. Patients is operated and the dracon prosthesis was exchanged to arterial homograft, which is more resistant to infections or subclavio-femoral bypasses. Removing of intestinal fistula included resection of duodenum and gastroenterotomy or duodenorrhaphy. The modification of duodenal fistula provision relies on duodenorraphy and protection of that area and prosthesis with pediculated flap of gastrocolic omentum conducted retrocolicaly in retroperitoneum space. The retrocolical and retroperitoneal omentoplasty seems to be a practical modification of aorto-duodenal fistula treatment with useful protection of duodenal plastic.

Carotid body resection for sympathetic modulation in systolic heart failure: results from first-in-man study.

AIMS: Augmented reflex responses from peripheral chemoreceptors, which are mainly localized in the carotid bodies (CBs), characterize patients with systolic heart failure and contribute to adrenergic hyperactivation. We investigated whether surgical resection of CBs in these patients can be performed safely to decrease sympathetic tone. METHODS AND RESULTS: We studied 10 male patients with systolic heart failure (age, 59 ± 3 years; LVEF, 27 ± 7%) who underwent unilateral right-sided CB resection (four patients) or bilateral CB resection (six patients). Primary endpoints of the study were changes in muscle sympathetic nerve activity (MSNA) and peripheral chemosensitivity measured as ventilatory response to hypoxia from baseline to 1 month post-CB resection. Safety analysis included analysis of arterial blood gas and oxygenation at night through 2 months post-procedure and adverse events assessed up to 12 months. At the 1-month visit, CB resection was associated with a significant decrease both in MSNA (86.6 ± 3.1 vs. 79.7 ± 4.2 bursts/100 beats, P = 0.03) and in peripheral chemosensitivity (1.35 ± 0.19 vs. 0.41 ± 0.17 L/min/SpO2 , P = 0.005). It also resulted in improved exercise tolerance. Amongst some patients with bilateral CB resection, there was a trend towards worsening of oxygen saturation at night, which in one case required therapy with non-invasive ventilation. CONCLUSION: We present first-in-man evidence that CB resection in patients with systolic heart failure is associated with a decrease in sympathetic activity. A bilateral procedure may carry a risk of worsening oxygenation at night. CB modulation constitutes an interesting research avenue, but careful consideration of the balance between safety and efficacy is necessary before further clinical trials.

[The surgical treatment of thoracic outlet syndrome]. / Leczenie chirurgiczne zespolu uciskowego górnego otworu klatki piersiowej.

UNLABELLED: In this paper the surgical treatment of thoracic outlet syndrome (TOS) is presented. MATERIAL AND METHODS: The investigation of 74 patients treated for vascular complications of the TOS the Paget-Schroetter syndrome and postthrombotic syndrome (27 patients), as well as upper limb ischemia and/or the subclavian artery aneurysm (14 patients) and for neurological complications of the TOS (33 patients) was performed. In case of venous thrombosis the treatment consisted of thrombolytic therapy and decompressive procedures that included transaxillary first rib resection and other surgical procedures that excise different anomalies in the region of the thoracic outlet. In case of complications associated with compression of the subclavian artery the operation consisted of resection of the first rib and accessory osseous and muscular pathological elements using supraclavicular and/or infraclavicular approach with implantation of vascular bypass were performed. In the neurological syndrome of TOS the operation consisted of transaxillary first rib resection and other surgical procedures that excise different anomalies in the region of the thoracic outlet. The therapy results were estimated with use of the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire of the American Academy of Orthopedic Surgeons. RESULTS: In case of venous complications the thrombolytic therapy was successful in all cases the restoration of complete patency was obtained. In all patients first rib was resected via transaxillary approach. The DASH questionnaire revealed the full return of upper limb function in most of patients. Improvement was obtained the in the cases with postthrombotic syndrome. In case of upper limb ischemia the improvement of blood flow was obtained after the subclavian-brachial bypass implantation (5 patients). In this group the DASH score showed return to full activity. In case of subclavian artery aneurysm surgery (9 patients) the DASH scale revealed worsening of limb function in 4 patients during the follow-up period. In the neurological syndrome of TOS the restoration of complete activity of limb was observed. The DASH scale revealed worsening of limb function in 4 patients during the follow-up period. CONCLUSIONS: The optimal therapy of vascular complications is multimodal treatment (thrombolysis or reconstructive vascular procedure with decompressive surgery). The surgical treatment of neurological TOS halts degradation of brachial splice. The decompression of neurovascular bundle in vascular TOS should include the first rib resection in each case.

[Presence of Chlamydia pneumoniae in the carotid artery]. / Wystepowanie Chlamydia pneumoniae w tetnicach szyjnych.

UNLABELLED: There is growing experimental evidence that Chlamydia pneumoniae is a risk factor and contribute to the development of atherosclerosis of carotid artery. This process might cause stenosis of carotid artery and TIA or stroke. AIM: Aim of this study was to evaluate the frequency of Ch. pneumoniae infection in carotid artery stenosis patients and in control group-healthy artery from multiorgan donors. MATERIAL AND METHODS: From each of 84 patients undergoing carotid endarterectomy the samples were analyzed by nested PCR for Ch. pneumoniae DNA. Furthermore we determined DNA Ch. pneumoniae in carotid artery from 20 multiorgan donors. RESULTS: In control group-healthy artery the PCR for Ch. pneumoniae was negative in all samples. Ch. pneumoniae was detected in 57 patients (67.85%) with symptomatic carotid artery stenosis, however in 27 patients (32.15%) the PCR test was negative. CONCLUSIONS: We did not observe infection of Ch. pneumoniae in healthy carotid artery-control group. We noted great frequency of infection in patients with stenosis of carotid artery. Patients with stenosis of carotid artery can be candidates to antibiotic therapy, which can slow down the progression of artery stenosis.

[Immunosuppression in the treatment of vascular prosthesis infection with arterial transplantation]. / Immunosupresja w leczeniu zakazen protez naczyniowych przeszczepami tetniczymi.

AIM: The purpose of this study is to evaluate the use of immunosuppression in treatment of prosthetic graft infections with arterial transplantation. MATERIAL AND METHODS: In this paper 29 cases of the massive aorto-ilio-femoral graft infection treated by the replacement of infected prosthesis with arterial homograft are presented. The arterial allograft was stored with application of cold ischemia method in preservation solution at 4 degrees C. During the follow up period the patients were divided into two groups: group received immunosuppressive regimen after surgery (n = 16) and group without immunosuppression (n = 13). The Duplex-Doppler ultrasound, the scintigraphy with use of Technetium-labeled leukocytes, bacteriological and antigenic examination and blood levels of Cyclosporin A were used in the diagnostic trial of infection and of the healing process of the homograft. In both groups there was performed evaluation of arterial wall by using the scanning electron microscopy. RESULTS: In the group with immunosuppression no complications due to the homograft's wall degradation and deficiency of cell mediated immunity in infections were noticed. In the group without immunosuppression there were observed complications related to the impairment of the allograft wall: in 3 cases--the graft rupture, in 2 cases--the graft true aneurysm and homograft thrombosis in 3 cases. CONCLUSION: The use of immunosuppression in transplantation of artery produces increase in survival rate and improves function of arterial graft.

[Incidence of factor VII and C3 in vascular anastomosis]. / Wystepowanie czynnika VII krzepniecia krwi oraz czynnika C3 ukladu dopelniacza w zespoleniach naczyniowych.

In order to study pathogenesis of vascular prosthesis healing process the following experiment was designed. 16 dogs underwent implantation of unilateral straight aorto-femoral teflon (PTFE, polytetrafluoroethylene) by-pass. After 6 months all dogs were killed, dissected and vascular prostheses with margin of adjacent aorta and femoral artery were collected for further study. Areas of proximal and distal anastomosis were examined immunohistochemically. Presence of coagulation factor VII, and C3 complement factor were studied. The obtained results were analyzed statistically by means of t-Student test. Factor VII as well C3 were found in areas of both proximal and distal anastomosis. Concentration of all two substances in proximal and distal anastomosis was compared. No statistically valid differences in factor VII concentration in proximal and distal anastomosis were found, whereas amounts of C3 factor as well as degree of extracellular matrix infiltration were markedly higher in distal anastomosis.

[Bilateral chemodectoma--a case report]. / Przypadek obustronnego guza klebka szyjnego.

Chemodectoma is exceptionally rarely tumor comes from the parasympathetic part of nervous system. Cases description first of all concern multiple, single tumors localized on the neck, occasionally somewhere else. Tumors expansion in internal carotid vein aperture or in ear provoke serious complications from cranial nerves paralysis to cerebellum lesion. In this paper authors present a case of bilateral chemodectoma. Surgical treatment has required--not only simple tumor excision but also internal carotid artery reimplantation.

Use of mesh fibrous dressing covered with fibrin glue (TachoComb) in hemostasis after vascular anastomoses in the groin.

We present in this paper application of haemostatic device TachoComb onto bleeding after vascular anastomosis of dacron vascular prosthesis (branch of aortobifemoral or bypass aortofemoral) with common femoral artery in the groin. Hemorrhagic complications have influence onto clinical status of operated patients. Haemostatic TachoComb dressing was applied at 30 cases and results were compared to control group consist of 25 cases, in which gas compresses were applied. Mean loss blood in group I with the usage of TachoComb was statistical characteristic (p < 0.003) smallest than in group II. Also mean time of hemostasis was shortest than in group II (p < 0.01). We proved that use of TachoComb limits bleeding from suture line connecting artery with vascular prosthesis.

Intraoperative hemostasis during kidney transplantation and the use collagen mesh dressing covered by fibrin glue (TachoComb).

In this paper we present influence of use of haemostatic dressing TachoComb, onto bleeding from surface of transplanted kidney. Kidney transplantation (KTX) seems to be main method of treatment of terminal renal failure. Enlarging number of KTX results in growing frequency of intra and postoperative complications. Hemorrhagic complications can impact clinical status of recipient and graft function. Haemostatic dressing was applied at 29 cases. Control group in which only gas compresses were used consisted of 25 patients. It was proved, that use of dressing from collagen mesh covered by fibrin glue TachoComb, after kidney transplantation diminished parenchymal bleeding and time necessary to get complete hemostasis.

The treatment of subclavian artery compression with the use of ringed polytetrafluoroethylene vascular prostheses.

UNLABELLED: In this paper the treatment of arterial complications of the Thoracic Outlet Syndrome (TOS) is presented. The investigation of 14 patients treated in the Department of Vascular, General and Transplantological Surgery of the Wroclaw Medical University for arterial complications of the TOS (as upper limb ischemia and/or the subclavian artery aneurysm in 14 patients) was performed. In case of complications associated with compression of the subclavian artery the operation consisted of resection of the first rib and accessory osseous and muscular pathological elements using supraclavicular and/or infraclavicular approach with implantation of externally supported ringed vascular polytetrafluoroethylene bypass (PTFE) were performed. The therapy results were estimated with use of The Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire of American Academy of Orthopedic Surgeons. RESULTS: In case of upper limb ischemia the improvement of blood flow was obtained after the subclavian-brachial bypass implantation (5 patients). In this group the DASH score showed return to full activity. In case of subclavian artery aneurysm surgery (9 patients) the DASH scale revealed worsening of limb function in 4 patients during follow-up period. The optimal therapy of vascular complications is the multimodal treatment (reconstructive vascular procedure with decompressive surgery). The decompression of neurovascular bundle in vascular TOS should include the first rib resection in each case.

The use of synthetic vascular prosthesis in the surgical treatment of secondary aorto-duodenal fistulas.

In this paper the methods with synthetic vascular prosthesis used in surgical treatment of the secondary aorto-intestinal fistula are presented. 10 cases of 22 patients treated in the years 1993-2003 for secondary aorto-intestinal fistulas as a complication of vascular prosthesis infection are analysed. In all patients the abdominal CT, scintigraphy with technetium 99m labeled leucocytes and endoscopy were performed. The patients underwent the operation of infected dacron prosthesis' replacement with silver/collagen coated prosthesis or extraanatomic bypass (subclavian to femoral). To close the intestinal fistula the duodenectomy with gastroenterostomy was performed or the duodenum was sutured and protected with the use of pedicled omentum. In 4 patients extraanatomic subclavian-femoral of polytetrafluoroethylene (PTFE) bypass was used. In these cases the intestinal surgery was composed of the partial duodenectomy with fistula excision and duodenal stumps formation followed by antecolic gastrojejunostomy with the Braun's enteroanastomosis and pyloroplasty. In this group 2 patients (50%) died in the follow up period. There were two extraanatomic bypass thromboses in the 30 days follow up and one amputation (25%). The infected vascular prosthesis was replaced with silver/collagen coated prosthesis in the 6 patients. In these cases duodenal fistula was closed with two layers of stitches and additionally protected with pedicled fragment of the greater omentum, which was sewn on the duodenum. In this group 1 patients (16.7%) died in the follow up period. In one case (16.7%) in 9 months after operation reinfection od silver prosthesis was observed. There were no significative differences (p = 0.45) in terms of early mortality between both group of patients. The treatment of the fistula is a difficult and hazardous surgical procedure, results of which are unpredictable.

The treatment of massive prosthetic grafts infections with the use of silver/collagen coated dacron vascular prosthesis.

In this paper the use of silver-coated medical prosthesis of massive aorto-bifemoral and ilio-femoral dacron graft infection with hemorrhage is presented. To solve this problem in situ replacement was attempted using silver-coated dacron vascular prosthesis more resistant to infection. 9 patients with this therapeutic method is reported. Although positive clinical effect was obtained, the scintigraphy and Duplex Doppler Ultrasound of implanted graft revealed its infection. In our opinion therefore application of silver-coated medical prosthesis should be very cautious and limited to the critical states.

Carotid body removal for treatment of chronic systolic heart failure.

BACKGROUND: Augmented reflex response from peripheral chemoreceptors characterises chronic heart failure (CHF), contributes to autonomic imbalance and exercise intolerance and predicts poor outcome. METHODS AND RESULTS: We present a case of a 56-year-old male patient with ischaemic CHF, who underwent surgical, unilateral carotid body resection to reduce peripheral chemosensitivity. At 2-month and 6-month follow-ups, we document a persistent decrease in peripheral chemosensitivity accompanied by an improvement in exercise capacity, sleep disordered breathing and quality of life. Autonomic balance was favourably affected as evidenced by improved heart rate variability and augmented cardiac baroreflex sensitivity. There were no procedure-related adverse events. CONCLUSIONS: Denervation of a carotid body may offer a clinical strategy to restore autonomic balance and improve morbidity in heart failure (NCT01653821).