A mobilization poster stimulates early in-hospital rehabilitation after cardiac surgery: a prospective sequential-group study.

BACKGROUND: Patients infrequently mobilize at the surgical ward after cardiac surgery. Inactivity results in prolonged hospital stay, readmissions and increased cardiovascular mortality. Next, the course of in-hospital mobilization activities for patients is unclear. The aim was to evaluate early mobilization after heart surgery with a mobilization poster on the Activity Classification Guide for Inpatient Activities score from the American College for Sports Medicine (ACSM). Second, to develop a Thorax Centrum Twente (TCT) score to assess distinctive activities performed. METHODS: A poster was developed for the Moving is Improving! study to stimulate hospital mobilization after heart surgery. In this sequential-group study at a cardiothoracic surgery ward, 32 patients were included in the usual care group and 209 patients in the poster mobilization group. Change of ACSM and TCT scores over time were both defined as primary endpoints. Secondary endpoints included length of stay and survival. A subgroup analysis for coronary artery bypass grafting (CABG) was performed. RESULTS: ACSM score increased during hospital stay (p < 0.001). No significant increase of ACSM score was observed with a mobilization poster (p = 0.27), nor in the CABG subgroup (p = 0.15). The poster increased mobility to chair, toilet, corridor (all p < 0.01) and cycle ergometer (p = 0.02) as measured by the activity-specific TCT scores, without differences in length of stay or survival. CONCLUSIONS: ACSM score measured day-to-day functional changes, without significant differences between the poster mobilization and usual care group. Actual activities measured with the TCT score did improve. The mobilization poster is now new standard care, and effects in other centers and other departments should be assessed. TRIAL REGISTRATION: This study does not fall under the ICMJE trial definition and was not registered.

Use of the Left Radial Artery as Vascular Access for Coronary Angiography and as a Bypass Conduit: A Clinical Dilemma?

PURPOSE: International coronary revascularization guidelines recommend both, transradial vascular access for coronary angiography/intervention and use of the radial artery as a conduit for coronary artery bypass grafting (CABG). These recommendations may pose a clinical dilemma, as transradial access exposes these arteries to vascular trauma which makes them potentially unsuitable as future grafts. In this study, we investigated the awareness and views of cardiologists on these guideline recommendations. METHODS: We performed semi-structured interviews with 50 cardiologists from 19 centers, who regularly perform coronary angiographies or interventions, and outlined clinical scenarios to evaluate their preference of vascular access. In addition, we assessed whether preference was related to sub-specialization. RESULTS: The interviewed cardiologists had 16 ± 9.3 years of professional experience. There were 23 (46%) cardiologists from 7 centers without percutaneous coronary intervention facilities, and 27 (56%) cardiologists from 12 interventional centers. All 50 (100%) cardiologists indicated familiarity with the guidelines, yet 28 (56%) said not to be familiar with the aforementioned dilemma, and 9 (18%) stated there was no dilemma at all. Responses did not differ significantly between interventional (n = 28) and non-interventional (n = 22) cardiologists; however, if the right radial artery was unavailable (e.g., occluded), interventional cardiologists more often said to prefer access via the left radial artery (18/28 (64%) vs. 5/22 (23%), p = 0.001). CONCLUSION: More than half of the interviewed cardiologists indicated that they had not realized that left transradial access preceding CABG may preclude later use of this artery as a conduit. Notably, in case of unavailability of the right radial artery, interventional cardiologists preferred left transradial access more often than non-interventional cardiologists.

Intraoperative transit time flow measurements during off-pump coronary artery bypass surgery: The impact of coronary stenosis on competitive flow.

BACKGROUND: Combining preoperative angiography findings with intraoperative transit time flow measurements (TTFM) may improve patency of coronary artery bypass grafts. Nevertheless, graft flow might be impaired by native coronary flow based on the severity of stenoses, with inferior long-term outcomes. This study investigates the impact of left anterior descending artery (LAD) stenosis on competitive flow measured in left internal mammary artery (LIMA) grafts during off-pump coronary artery bypass grafting. METHODS: Fifty patients were included in this prospective single-center cohort study. LAD stenosis was assessed with quantitative coronary analysis (QCA) and stratified into three groups based on its severity. TTFM of LIMA grafts were performed with LAD open and temporarily occluded. Change in mean graft flow after LAD snaring was the primary endpoint. Secondary endpoints included further TTFM parameters, clinical outcomes, and competitive flow index (CFI), defined as the ratio of mean graft flow with open or closed LAD. RESULTS: Mean LAD stenosis as objectified with QCA was 58 ± 15%. Mean LIMA graft flow increased from 20 ml/min with open LAD to 30 ml/min with snared LAD (p < .001). TTFM cut-off values for graft patency improved in 26%-42% of patients after LAD occlusion. Median CFI was 0.66 (IQR: 0.56-0.82). Postoperative myocardial infarction occurred in 2.0% of patients, 120-day mortality was 0%, and 2-year mortality was 6.0%. CONCLUSIONS: Routine snaring of the LAD with CFI calculation during coronary artery bypass grafting is useful to detect significant competitive flow in LIMA grafts, potentially preventing unnecessary intraoperative graft revisions.

Objective Quantification of In-Hospital Patient Mobilization after Cardiac Surgery Using Accelerometers: Selection, Use, and Analysis.

Cardiac surgery patients infrequently mobilize during their hospital stay. It is unclear for patients why mobilization is important, and exact progress of mobilization activities is not available. The aim of this study was to select and evaluate accelerometers for objective qualification of in-hospital mobilization after cardiac surgery. Six static and dynamic patient activities were defined to measure patient mobilization during the postoperative hospital stay. Device requirements were formulated, and the available devices reviewed. A triaxial accelerometer (AX3, Axivity) was selected for a clinical pilot in a heart surgery ward and placed on both the upper arm and upper leg. An artificial neural network algorithm was applied to classify lying in bed, sitting in a chair, standing, walking, cycling on an exercise bike, and walking the stairs. The primary endpoint was the daily amount of each activity performed between 7 a.m. and 11 p.m. The secondary endpoints were length of intensive care unit stay and surgical ward stay. A subgroup analysis for male and female patients was planned. In total, 29 patients were classified after cardiac surgery with an intensive care unit stay of 1 (1 to 2) night and surgical ward stay of 5 (3 to 6) nights. Patients spent 41 (20 to 62) min less time in bed for each consecutive hospital day, as determined by a mixed-model analysis (p < 0.001). Standing, walking, and walking the stairs increased during the hospital stay. No differences between men (n = 22) and women (n = 7) were observed for all endpoints in this study. The approach presented in this study is applicable for measuring all six activities and for monitoring postoperative recovery of cardiac surgery patients. A next step is to provide feedback to patients and healthcare professionals, to speed up recovery.

Shorter RSPV cryoapplications result in less phrenic nerve injury and similar 1-year freedom from atrial fibrillation.

BACKGROUND: In the 123-study, we prospectively assessed, in a randomized fashion, the minimal cryoballoon application time necessary to achieve pulmonary vein (PV) isolation (PVI) in patients with paroxysmal atrial fibrillation (AF) with the aim to reduce complications by shortening the application duration. The first results of this study demonstrated that shortened cryoballoon applications (<2 minutes) resulted in less phrenic nerve injury (PNI) without compromising acute isolation efficacy for the right PVs. We now report the 1-year follow-up results regarding safety and efficacy of shorter cryoballoon applications. METHODS: A total of 222 patients with AF were randomized to two applications of 1 min "short," 2 min "medium," or 3 min "long" duration, 74 per group. Recurrence of AF and PV reconduction at 1-year follow-up were assessed. RESULTS: The overall 1-year freedom from AF was 79% and did not differ significantly between the short, medium, and long application groups (77%, 74%, and 85% for short, medium, and long application groups, respectively; P = 0.07). In 30 patients, a redo PVI procedure was performed. For all four PVs, there was no significant difference in reconduction between the three groups. Reconduction was most common in the left superior PV (57%). The right superior PV (RSPV) showed significantly less reconduction (17%) compared to the other PVs. CONCLUSIONS: Shortening cryoballoon applications of the RSPV to <2 minutes results in less PNI, while acute success and 1-year freedom from AF are not compromised. Therefore, shorter cryoballoon applications (especially) in the RSPV could be used to reduce PNI.

Shorter cryoballoon applications times do effect efficacy but result in less phrenic nerve injury: Results of the randomized 123 study.

BACKGROUND: The second-generation cryoballoon significantly improves outcome of pulmonary vein isolation (PVI) but may cause more complications than the first generation. Currently, no consensus regarding optimal cryoballoon application time exists. The 123-study aimed to assess the minimal cryoballoon application duration necessary to achieve PVI (primary endpoint) and the effect of application duration on prevention of phrenic nerve injury (PNI). METHODS: Patients <75 years of age with paroxysmal atrial fibrillation, normal PV anatomy, and left atrial size <40 cc/m² or <50 mm were randomized to two applications of different duration: "short," "medium," or "long." A total of 222 patients were enrolled, 74 per group. RESULTS: Duration per application was 105 (101-108), 164 (160-168), and 224 (219-226) s and isolation was achieved in 79, 89, and 90% (P < 0.001) of the PVs after two applications in groups short, medium, and long, respectively. Only for the left PVs, the success rate of the short group was significantly less compared to the medium- and long-duration groups (P < 0.001). PNI during the procedure occurred in 19 PVs (6.5%) in the medium and in 20 PVs (6.8%) in the long duration groups compared to only five PVs (1.7%) in the short duration group (P < 0.001). CONCLUSIONS: Short cryoballoon ablation application times, less than 2 min, did affect the success for the left PVs but not for the right PVs and resulted in less PNI. A PV tailored approach with shorter application times for the right PVs might be advocated.

Randomized Trial of Miniaturized Versus Standard Extracorporeal Circulation in Aortic Valve Surgery.

BACKGROUND: Complications related to extracorporeal circulation remain serious. Although a minimal invasive extra corporeal circulation (MiECC) system was developed to cope with these complications, its effectivity on patient-related outcomes such as blood loss remain uncertain. Therefore, the aim of this study is to compare MiECC to an advanced standard system with respect to blood loss. METHODS: A total of 128 adult patients undergoing elective isolated aortic valve replacement were enrolled in a randomized clinical trial. Patients who had undergone previous heart surgery and with preexisting kidney failure were excluded. The primary end point was postoperative blood loss after 12 hours and at drain removal. Secondary end points included intensive care and total length of stay and intubation time. At 1 hour and 12 hours after surgery, clinical laboratory data were determined. Early clinical outcomes and long-term survival were determined. RESULTS: MiECC patients (n = 63) had a significant lower blood loss (230 mL, 95% confidence interval: 203 to 261 mL) than regular patients (n = 62) after 12 hours (288 mL, 95% confidence interval: 241 to 344 mL, p = 0.04). A preservation of hemoglobin levels 1 hour and 12 hours after surgery in the MiECC group were observed (p < 0.001). No difference was found in early clinical outcomes and long-term survival. CONCLUSIONS: This randomized controlled trial compares MiECC and an advanced system for aortic valve replacement with blood loss as primary end point. We conclude that using MiECC is clinically equal for short- and long-term follow-up regarding blood loss. CLINICAL TRIAL REGISTRATION: NTR3378.

Long-Term Outcome of Consecutive Patients With Previous Coronary Bypass Surgery, Treated With Newer-Generation Drug-Eluting Stents.

BACKGROUND: Percutaneous coronary intervention (PCI) in patients with previous coronary artery bypass grafting (CABG) is associated with adverse clinical events. Although newer generation drug-eluting stents showed favorable short-term safety profiles, there is a lack of long-term outcome data. We evaluated the impact of previous CABG on 5-year clinical outcomes of patients treated with PCI using newer-generation drug-eluting stents. METHODS AND RESULTS: In this patient-level pooled analysis of the prospective TWENTE (The Real-World Endeavor Resolute versus Xience V Drug-Eluting Stent Study in Twente) trial and nonenrolled TWENTE registry, we assessed a consecutive series of patients who underwent PCI with newer-generation drug-eluting stents for non-ST-segment-elevation acute coronary syndromes or stable angina. Of all 1709 patients, 202 (11.8%) had a history of CABG. Patients with previous CABG had significantly higher 5-year rates of cardiac death (10.4% versus 4.3%; P<0.001) and target vessel revascularization (25.0% versus 8.1%; P<0.001). These differences remained statistically significant after adjustment for differences in baseline characteristics. Landmark analysis revealed that from 1- to 5-year follow-up, the rates of cardiac death (8.1% versus 3.2%; P<0.001) and target vessel revascularization (17.1% versus 5.9%; P<0.001) were significantly higher in patients with previous CABG. Among patients with a history of CABG, PCI of an obstructed vein graft was associated with a higher rate of 5-year target vessel revascularization (P=0.003). CONCLUSIONS: At 5-year follow-up after PCI with newer-generation drug-eluting stents, the risk of cardiac death and target vessel revascularization was significantly higher in patients with previous CABG. The target vessel revascularization rate was highest in patients who underwent PCI of obstructed vein grafts.

Supercritical carbon dioxide decellularised pericardium: Mechanical and structural characterisation for applications in cardio-thoracic surgery.

INTRODUCTION: Many biomaterials are used in cardio-thoracic surgery with good short-term results. However, calcification, dehiscence, and formation of scar tissue are reported. The aim of this research is to characterise decellularised pericardium after supercritical carbon dioxide (scCO2) processing as an alternative biological material for uses in cardio-thoracic surgery. METHODS: Porcine and bovine pericardium were decellularised using scCO2. Mechanical properties such as tensile strength, elastic modulus, fracture toughness and suture retention strength were determined. Ultrastructure was visualised using Scanning Electron Microscopy. Water uptake and swelling was experimentally determined. Commercially available glutaraldehyde treated bovine pericardium was used as gold standard for comparison. RESULTS: scCO2 decellularised porcine (and bovine pericardium) maintained their tensile strength compared to untreated native pericardium (13.3 ± 2.4MPa vs 14.0 ± 4.1MPa, p = 0.73). Tensile strength of glutaraldehyde treated pericardium was significantly higher compared to untreated pericardium (19.4 ± 7.3MPa vs 10.2 ± 2.2MPa, p = 0.02). Suture retention strength of scCO2 treated pericardium was significantly higher than glutaraldehyde treated pericardium (p = 0.01). We found no anisotropy of scCO2 or glutaraldehyde treated pericardium based on a trouser tear test. Ultrastructure was uncompromised in scCO2 treated pericardium, while glutaraldehyde treated pericardium showed deterioration of extracellular matrix. CONCLUSION: scCO2 processing preserves initial mechanical and structural properties of porcine and bovine pericardium, while glutaraldehyde processing damages the extracellular matrix of bovine pericardium. Decellularisation of tissue using scCO2 might give long-term solutions for cardio-thoracic surgery without compromising initial good mechanical properties.

Impact of Modified Transesophageal Echocardiography on Mortality and Stroke after Cardiac Surgery: A Large Cohort Study.

The aim of this study was to investigate the impact of perioperative screening with modified transesophageal echocardiography (A-View method). We compared, in consecutive patients who underwent cardiac surgery between 2006 and 2014, 30-day mortality and in-hospital stroke incidence, operated either with perioperative modified TEE screening (intervention group) or only with conventional TEE screening (control group). Of the 8,605 study patients, modified TEE was applied in 1,391 patients (16.2%). Patients in the intervention group were on average older (71 versus 68 years, p < 0.001) and more often females (31.0% versus 28.0%, p < 0.001) and had a higher predicted mortality (EuroSCORE I: 5.9% versus 4.0%, p < 0.001). The observed 30-day mortality was 2.2% and 2.5% in both groups, respectively, with multivariable and propensity-score adjusted relative risks (RRs) of 0.70 (95% CI: 0.50-1.00, p = 0.05) and 0.67 (95% CI: 0.45-0.98, p = 0.04). In-hospital stroke was 2.9% and 2.1% in both groups, respectively, with adjusted RRs of 1.03 (95% CI: 0.73-1.45) and 1.01 (95% CI: 0.71-1.43). In patients undergoing cardiac surgery, use of perioperative screening for aortic atherosclerosis with modified TEE was associated with lower postoperative mortality, but not stroke, as compared to patients operated on without such screening.

A Protocol for Diagnosis and Management of Aortic Atherosclerosis in Cardiac Surgery Patients.

In patients undergoing cardiac surgery, use of perioperative screening for aortic atherosclerosis with modified TEE (A-View method) was associated with lower postoperative mortality, but not stroke, as compared to patients operated on without such screening. At the time of clinical implementation and validation, we did not yet standardize the indications for modified TEE and the changes in patient management in the presence of aortic atherosclerosis. Therefore, we designed a protocol, which combined the diagnosis of atherosclerosis of thoracic aorta and the subsequent considerations with respect to the intraoperative management and provides a systematic approach to reduce the risk of cerebral complications.

Model predictive control of a robotically actuated delivery sheath for beating heart compensation.

Minimally invasive surgery (MIS) during cardiovascular interventions reduces trauma and enables the treatment of high-risk patients who were initially denied surgery. However, restricted access, reduced visibility and control of the instrument at the treatment locations limits the performance and capabilities of such interventions during MIS. Therefore, the demand for technology such as steerable sheaths or catheters that assist the clinician during the procedure is increasing. In this study, we present and evaluate a robotically actuated delivery sheath (RADS) capable of autonomously and accurately compensating for beating heart motions by using a model-predictive control (MPC) strategy. We develop kinematic models and present online ultrasound segmentation of the RADS that are integrated with the MPC strategy. As a case study, we use pre-operative ultrasound images from a patient to extract motion profiles of the aortic heart valve (AHV). This allows the MPC strategy to anticipate for AHV motions. Further, mechanical hysteresis in the steering mechanism is compensated for in order to improve tip positioning accuracy. The novel integrated system is capable of controlling the articulating tip of the RADS to assist the clinician during cardiovascular surgery. Experiments demonstrate that the RADS follows the AHV motion with a mean positioning error of 1.68 mm. The presented modelling, imaging and control framework could be adapted and applied to a range of continuum-style robots and catheters for various cardiovascular interventions.

Modified transesophageal echocardiography of the dissected thoracic aorta; a novel diagnostic approach.

BACKGROUND: Transesophageal echocardiography (TEE) is a key diagnostic modality in patients with acute aortic dissection, yet its sensitivity is limited by a "blind-spot" caused by air in the trachea. After placement of a fluid-filled balloon in the trachea visualization of the thoracic aorta becomes possible. This method, modified TEE, has been shown to be an accurate test for the diagnosis of upper aortic atherosclerosis. In this study we discuss how we use modified TEE for the diagnosis and management of patients with (suspected) acute aortic dissection. NOVEL DIAGNOSTIC APPROACH OF THE DISSECTED AORTA: Modified TEE provides the possibility to obtain a complete echocardiographic overview of the thoracic aorta and its branching vessels with anatomical and functional information. It is a bedside test, and can thus be applied in hemodynamic instable patients who cannot undergo computed tomography. Visualization of the aortic arch allows differentiation between Stanford type A and B dissections and visualization of the proximal cerebral vessels enables a timely identification of impaired cerebral perfusion. During surgery modified TEE can be applied to identify the true lumen for cannulation, and to assure that the true lumen is perfused. Also, the innominate- and carotid arteries can be assessed for structural integrity and adequate perfusion during multiple phases of the surgical repair. CONCLUSIONS: Modified TEE can reveal the "blind-spot" of conventional TEE. In patients with (suspected) aortic dissection it is thus possible to obtain a complete echocardiographic overview of the thoracic aorta and its branches. This is of specific merit in hemodynamically unstable patients who cannot undergo CT. Modified TEE can guide also guide the surgical management and monitor perfusion of the cerebral arteries.

Imaging Techniques for Diagnosis of Thoracic Aortic Atherosclerosis.

The most severe complications after cardiac surgery are neurological complications including stroke which is often caused by emboli merging from atherosclerosis in the ascending aorta to the brain. Information about the thoracic aorta is crucial in reducing the embolization risk for both surgical open and closed chest procedures such as transaortic heart valve implantation. Several techniques are available to screen the ascending aorta, for example, transesophageal echocardiography (TEE), epiaortic ultrasound, TEE A-view method, manual palpation, computed tomography, and magnetic resonance imaging. This paper provides a description of the advantages and disadvantages of these imaging techniques.

Off-pump no-touch technique: 3-year results compared with the SYNTAX trial.

OBJECTIVES: A 3-year follow-up of a retrospective, single-centre clinical study of OPCAB (off-pump coronary artery bypass) no-touch technique with arterial composite grafts and an indirect comparison with clinical outcomes of the 3-year follow-up of the SYNTAX trial. METHODS: A total of 400 consecutive patients ('all-comers') who underwent OPCAB no-touch coronary surgery. Primary endpoint was 3-year MACCE (major adverse cardiovascular and cerebrovascular events). These results were compared with the randomized arms of the SYNTAX trial. RESULTS: The observed 3-year survival was 82.2%. The cumulative 3-year freedom from MACCE was 89.7%. The percentage of MACCE was significantly lower (P < 0.001) in the OPCAB no-touch group (10.3%) compared with both arms of the SYNTAX trial (20.2 and 28.0%, respectively). Repeat revascularization in the OPCAB no-touch group (4.3%) was significantly lower (P < 0.001) compared with both arms of the SYNTAX trial (10.7 and 19.7%, respectively). The percentage of stroke was significantly lower (P = 0.032) in the OPCAB no-touch group compared with the CABG arm in the SYNTAX trial (1.3 vs 3.4%). There was no significant difference of stroke rate between the OPCAB no-touch group and the PCI arm of the SYNTAX trial (1.3 vs 2%, P = 0.347). CONCLUSIONS: The results at the 3-year follow-up showed the safety and efficacy of OPCAB no-touch technique. The OPCAB no-touch technique may improve patients' outcome by minimizing the morbidity and the neurological complications. Prospective controlled trials are needed to confirm these results.

Impact of previous coronary artery bypass surgery on clinical outcome after percutaneous interventions with second generation drug-eluting stents in TWENTE trial and non-enrolled TWENTE registry.

BACKGROUND: Patients with previous coronary artery bypass grafting (CABG) who underwent percutaneous coronary intervention (PCI) have an increased repeat revascularization rate, but data on contemporary second-generation drug-eluting stents (DES) are scarce. METHODS: We evaluated 1-year clinical outcome following secondary revascularization by PCI in patients of the TWENTE trial and non-enrolled TWENTE registry, and compared patients with previous CABG versus patients without previous CABG. RESULTS: Of all 1709 consecutive patients, 202 (11.8%) had previously undergone CABG (on average 11.2±8.5 years ago). CABG patients were older (68.5±9.4 years vs. 64.1±10.7 years, P<0.001) and more often had diabetes (28.7% vs. 20.9%, P=0.01) and previous PCI (40.1% vs. 19.8%, P<0.001) compared to patients without previous CABG. Nevertheless, a higher target vessel revascularization (TVR) rate following PCI in the CABG patients (9.4% vs. 2.3%, P<0.001) was the only significant difference in clinical outcome at 1-year follow-up (available for 99.6%). Among CABG patients, the TVR rate was significantly higher in patients treated for graft lesions (n=65; 95.4% in vein grafts) than in patients treated for native coronary lesions only (n=137) (18.5% vs. 5.1%, P=0.002). Among 1638 patients with PCI of native coronary lesions only, there was only a non-significant difference in TVR between patients with previous CABG versus patients without previous CABG (5.1% vs. 2.3%, P=0.08). CONCLUSIONS: Patients with previous CABG showed a favorable safety profile after PCI with second-generation DES. Nevertheless, their TVR rate was still much higher, driven by more repeat revascularizations after PCI of degenerated vein grafts. In native coronary lesions, there was no such difference.

Laser speckle contrast analysis for quantifying the Allen test: a feasibility study.

BACKGROUND AND OBJECTIVE: The radial artery has become a routinely used conduit for coronary artery bypass graft surgery (CABG). Prior to surgery the Allen test is performed to test the patency of the ulnar artery. A positive Allen test, reperfusion >5 seconds, suggests an insufficient perfusion of the hand by the ulnar artery. In this study we investigated if laser speckle contrast analysis (LASCA) provides an objective determination of the reperfusion time. MATERIALS AND METHODS: When the hand is illuminated with coherent laser light, the backscattered light will result in an interference pattern consisting of bright and dark areas called speckles. This speckle pattern will change due to movement of red blood cells. LASCA uses these changes to visualize the perfusion during the Allen test. Reperfusion is measured on the palmar side of the hand. The reperfusion time is defined as the time from onset of reperfusion to maximum perfusion calculated by a polynomial curve fit. The reperfusion time of the hand of patients undergoing CABG (n = 30) is measured using LASCA and is compared to the conventional Allen test performed by the nurse practitioner. RESULTS: LASCA measurements showed a negative Allen test of both hands of 16 patients. Fourteen had a borderline reperfusion time of 5-6 seconds and/or a positive Allen test of one or both hands. No statistical significant difference was observed for the LASCA Allen test compared to the conventional Allen test, P = 0.549 for the left hand and P = 0.223 for the right hand. CONCLUSION: LASCA is able to visualize perfusion of the hand and measure a quick, moderate, slow reperfusion response or no reperfusion. It is technically feasible to determine the reperfusion time of the hand. LASCA can be a useful and objective tool to assess ulnar collateral blood supply to the hand prior to harvesting of the radial artery as a bypass graft.

Adventitial dissection: a simple and effective way to reduce radial artery spasm in coronary bypass surgery.

OBJECTIVES: Over the last two decades, the radial artery (RA) has become a routinely used conduit for coronary artery bypass graft surgery. One potential disadvantage of the radial artery is its higher susceptibility to vasospasm compared with other arterial grafts. We investigated whether adventitial dissection of the radial artery can reduce vasoconstriction and increase free blood flow. METHODS: Following harvesting, the adventitia of the radial artery was dissected using coronary scissors. Surplus distal radial artery segments (n = 35) with and without adventitial dissection of patients undergoing coronary artery bypass surgery were collected and pairwise assessment of vasoreactivity to potassium chloride, U46619 and acetylcholine was performed in organ bath experiments. Free blood flow was measured before and after adventitial dissection. RESULTS: Full curve and maximal vasoconstriction of the RA to potassium chloride (P = 0.015 and 0.001) and U46619 (P = 0.048 and 0.001) was significantly reduced after adventitial dissection compared with non-adventitial dissected radial arteries. Endothelium-dependent relaxation to acetylcholine of adventitial dissected radial arteries was significantly increased (P = 0.006) compared with non-adventitial dissected radial arteries. Maximal vasorelaxation to acetylcholine was significantly increased for adventitial dissected radial arteries compared with non-adventitial dissected radial arteries (P = 0.018). Free blood flow was significantly increased after adventitial dissection (P = 0.037). CONCLUSIONS: The adventitial dissected radial artery is less susceptible to vasoconstriction and more prone to vasorelaxation ex vivo and shows an increased free blood flow. Therefore, we suggest adventitial dissection of the radial artery graft to reduce vasospasm for arterial revascularization in coronary artery bypass surgery.