Cardiogenic Shock After Arterial Y-Graft Coronary Bypass Surgery Secondary to Critical Stenoses of the Left Subclavian and Left Main Coronary Arteries.

We present a case of a 62-year-old man who was in cardiogenic shock. He had a history of coronary artery bypass grafting 4 years previously, with left internal mammary radial artery Y-grafting to a left dominant coronary circulation. Critical stenoses of the left main coronary and left subclavian arteries were seen at angiography. An occluded abdominal aorta precluded the use of mechanical circulatory support. The patient underwent high-risk stenting of the left subclavian artery with a successful outcome. The case highlights the unresolved issue of screening for subclavian stenoses in patients being considered for revascularization with arterial Y-grafting.

Noninvasive Estimation of Pressure Changes Using 2-D Vector Velocity Ultrasound: An Experimental Study With In Vivo Examples.

A noninvasive method for estimating intravascular pressure changes using 2-D vector velocity is presented. The method was first validated on computational fluid dynamic (CFD) data and with catheter measurements on phantoms. Hereafter, the method was tested in vivo at the carotid bifurcation and at the aortic valve of two healthy volunteers. Ultrasound measurements were performed using the experimental scanner SARUS, in combination with an 8 MHz linear array transducer for experimental scans and a carotid scan, whereas a 3.5-MHz phased array probe was employed for a scan of an aortic valve. Measured 2-D fields of angle-independent vector velocities were obtained using synthetic aperture imaging. Pressure drops from simulated steady flow through six vessel geometries spanning different degrees of diameter narrowing, running from 20%-70%, showed relative biases from 0.35% to 12.06%, depending on the degree of constriction. Phantom measurements were performed on a vessel with the same geometry as the 70% constricted CFD model. The derived pressure drops were compared to pressure drops measured by a clinically used 4F catheter and to a finite-element model. The proposed method showed peak systolic pressure drops of -3 kPa ± 57 Pa, while the catheter and the simulation model showed -5.4 kPa ± 52 Pa and -2.9 kPa, respectively. An in vivo acquisition of 10 s was made at the carotid bifurcation. This produced eight cardiac cycles from where pressure gradients of -227 ± 15 Pa were found. Finally, the aortic valve measurement showed a peak pressure drop of -2.1 kPa over one cardiac cycle. In conclusion, pressure gradients from convective flow changes are detectable using 2-D vector velocity ultrasound.

Assessment of EVAR Competence: Validity of a Novel Rating Scale (EVARATE) in a Simulated Setting.

OBJECTIVES: The aims of this study were to investigate the validity evidence for a novel procedure specific assessment tool of competence in endovascular aortic repair (EVAR) and to establish a pass/fail level for the assessment. METHODS: Computed tomography angiography data of a 55 mm in diameter infrarenal aortic aneurysm was implemented into an endovascular simulator. Twenty-three physicians with varying EVAR experiences were video-recorded when performing a standard EVAR procedure on the simulator. Two experienced EVAR operators assessed the participants using the novel rating scale, "EndoVascular Aortic Repair Assessment of Technical Expertise" (EVARATE). Validity was studied according to the framework endorsed by the American Educational Research Association. RESULTS: The EVARATE scale had a high internal consistency (Cronbach's alpha = .90). The inter-rater reliability was acceptable (Intraclass Correlation Coefficient = .68, p = .005). Specific EVAR experience correlated significantly with the EVARATE score (Spearman's rho = .62, p = .002), but general endovascular experience did not. Consequence analysis showed that the EVARATE assessment could distinguish novices from intermediates (p < .01) and from experts (p < .001). A pass/fail score was determined using the contrasting groups' method. CONCLUSION: This paper presents the initial validity evidence for a novel procedure specific assessment tool, EVARATE, for operator competence in endovascular aortic repair investigated in a simulated setting. The assessment tool can be used to provide structured formative feedback to trainees.

Safety and efficacy of using the Viabahn endoprosthesis for percutaneous treatment of vascular access complications after transfemoral aortic valve implantation.

Vascular access complications (VACs) remain one of the biggest challenges when performing transcatheter aortic valve implantation (TAVI). This study aimed to investigate the short- and medium-term safety and efficacy of the Viabahn endoprosthesis (Gore, Flagstaff, AZ) when used to treat TAVI-induced vascular injury. Over a 40-month period, 354 patients underwent true percutaneous transfemoral (TF)-TAVI using a CoreValve and Prostar-XL closure system; this was our study population. A VAC leading to acute intervention occurred in 72 patients (20.3%) - of these, 18 were managed by balloon angioplasty, 48 were treated by Viabahn stenting (technical success rate 98%), and 6 needed surgical intervention. Overall, this approach resulted in a major VAC rate of 3.1% (n = 11) in our study cohort. Length of hospitalization and 30-day mortality rates were comparable in patients with a VAC treated by Viabahn stenting versus patients without vascular complications. Two patients (4.5%) presented with new-onset claudication; one of them had the stent implanted covering the deep femoral artery (DFA). At medium-term follow-up (median 372 days; range 55 to 978 days) duplex ultrasound showed 100% patency of the Viabahn endoprostheses with no signs of stent fracture or in-stent stenosis/occlusion. In conclusion, the use of self-expanding covered stents is safe and effective in case of TF-TAVI-induced vascular injury, with good short- and medium-term outcomes. Importantly, coverage of the DFA should be avoided. If confirmed by long-term (>5 years) follow-up studies, this strategy for treating TAVI-induced VAC may be used routinely in high-risk patients.

Association between endovascular performance in a simulated setting and in the catheterization laboratory.

INTRODUCTION: Simulation-based assessment studies have related simulator performance to clinical experience instead of actual clinical performance. This study validates a novel rating scale for coronary angiography (CA) performance and at the same time explores the association between CA performance in a simulated setting and in the catheterization laboratory. METHODS: Ten cardiologists and cardiology residents with varying degrees of CA experience performed 2 CAs in the catheterization laboratory and 2 CAs in a simulated setting. The residents had prior simulator experience opposite cardiologists. Two raters assessed the operators' video-recorded performances using the novel CA rating scale (CARS). RESULTS: The correlation between CARS scores in the catheterization laboratory and the simulated setting was R = 0.20 (P = 0.195). Residents' scores were higher in the simulated setting than in the catheterization laboratory. The correlation between operators' previous clinical experience in CA and CARS scores was R = 0.65 (P = 0.005) in the catheterization laboratory and R = 0.11 (P = 0.353) in the simulated setting. CONCLUSIONS: The association between CA performance in a simulated setting and actual performance in the catheterization laboratory is not linear. The novel rating scale for CA (CARS) seems to be a valid proficiency assessment instrument in the catheterization laboratory. Familiarity with the simulator may overestimate proficiency, which means that simulator performance as a predictor of clinical performance should be interpreted with caution.

Fine-motor skills testing and prediction of endovascular performance.

BACKGROUND: Performing endovascular procedures requires good control of fine-motor digital movements and hand-eye coordination. Objective assessment of such skills is difficult. Trainees acquire control of catheter/wire movements at various paces. However, little is known to what extent talent plays for novice candidates at entry to practice. PURPOSE: To study the association between performance in a novel aptitude test of fine-motor skills and performance in simulated procedures. MATERIAL AND METHODS: The test was based on manual course-tracking using a proprietary hand-operated roller-bar device coupled to a personal computer with monitor view rotation. A total of 40 test repetitions were conducted separately with each hand. Test scores were correlated with simulator performance. Group A (n = 14), clinicians with various levels of endovascular experience, performed a simulated procedure of contralateral iliac artery stenting. Group B (n = 19), medical students, performed 10 repetitions of crossing a challenging aortic bifurcation in a simulator. RESULTS: The test score differed markedly between the individuals in both groups, in particular with the non-dominant hand. Group A: the test score with the non-dominant hand correlated significantly with simulator performance assessed with the global rating scale SAVE (R = -0.69, P = 0.007). There was no association observed from performances with the dominant hand. Group B: there was no significant association between the test score and endovascular skills acquisition neither with the dominant nor with the non-dominant hand. CONCLUSION: Clinicians with increasing levels of endovascular technical experience had developed good fine-motor control of the non-dominant hand, in particular, that was associated with good procedural performance in the simulator. The aptitude test did not predict endovascular skills acquisition among medical students, thus, cannot be suggested for selection of novice candidates. Procedural experience and practice probably supplant the influence of innate abilities (talent) over time.

Simulation: moving from technology challenge to human factors success.

Recognition of the many limitations of traditional apprenticeship training is driving new approaches to learning medical procedural skills. Among simulation technologies and methods available today, computer-based systems are topical and bring the benefits of automated, repeatable, and reliable performance assessments. Human factors research is central to simulator model development that is relevant to real-world imaging-guided interventional tasks and to the credentialing programs in which it would be used.

Use of performance curves in estimating number of procedures required to achieve proficiency in coronary angiography.

BACKGROUND: Current guidelines in cardiology training programs recommend 100-300 coronary angiography procedures for certification. We aimed to assess the number of procedures needed to reach sufficient proficiency. METHODS: Procedure time, fluoroscopy time, dose area product (DAP), and contrast media volume were used as indicators of quality of performance. We analyzed data from 4,200 coronary angiographies. Performance curves of seven trainees were compared with recommended reference levels and to those of seven interventional cardiologists. RESULTS: On average, the number of procedures needed for trainees to reach recommended reference levels was estimated as 226 and 353, for DAP and use of contrast media, respectively. After 300 procedures, trainees' procedure time, fluoroscopy time, DAP, and contrast media volume were significantly higher compared with experts' performance, P < 0.001 for all parameters. To approach the experts' level of DAP and contrast media use, trainees need 394 and 588 procedures, respectively. Performance curves showed large individual differences in the development of competence. CONCLUSION: On average, trainees needed 300 procedures to reach sufficient level of proficiency, and this is in accordance with current guidelines. However, because of large individual differences, performance curves might be useful in monitoring individual trainees' progress and ensure documentation of sufficient competence when dealing with patients at risk.

Long-term outcome of lung transplantation for cystic fibrosis--Danish results.

OBJECTIVE: Over the last decades improvements in medical therapies have delayed the progression of lung disease in cystic fibrosis (CF). However, lung disease is still the most common cause of premature death, and lung transplantation today is the only treatment for end-stage lung disease in patients with CF. We present a retrospective review of the outcome of CF patients transplanted in Denmark since start of the national lung transplantation programme in 1992. METHODS: In a 10-year period, 47 patients with CF were listed for lung transplantation; 29 patients underwent transplantation and 18 patients died while waiting for donor organs. Eleven patients received en block double lung transplantation with direct bronchial artery revascularization and 18 patients received bilateral sequential lung transplantation. Median age at transplantation was 29 years (range 11-50). RESULTS: The perioperative mortality (< or =30 days) was 3.5% (1/29 patients). Actuarial survival of transplanted patients at 1, 3, 5 and 8 years was 89, 80, 80 and 70%, respectively. Actuarial survival of non-transplanted patients on the waiting list at 1 and 2 years was 28 and 11% (P<0.0001). Causes of death of transplanted patients were: respiratory failure on day 7 (n=1), bronchiolitis obliterans syndrome (n=2), infection (Cytomegalovirus, Aspergillus fumigatus) (n=2), bronchial anastomosis dehiscence (n=1). Pulmonary function (FEV1% predicted) improved from median 20% (range 13-31) pre-transplant to 71% (range 19-118) after 5 years (P<0.0001). Renal function (51Cr-EDTA clearance) decreased from median 97 ml/min (range 45-190) pre-transplant to 32 ml/min (range 8-84) 6 months after transplantation (P<0.001). Three patients (11%) received dialysis post-transplant of whom two underwent kidney transplantation. Immunosuppressive induction therapy with rabbit-antithymocyte-globulin compared to daclizumab resulted in fewer treatments for acute rejection within the first 3 months post-transplant (P=0.05 at 5-8 weeks). Burkholderia multivorans was present in three patients pre-transplant with satisfying long-term outcome in one patient. CONCLUSIONS: Lung transplantation is a well-established life-extending treatment for patients with CF and end-stage lung disease. The operative mortality is low and CF patients have a significant early survival benefit after lung transplantation. Satisfying long-term results can be achieved in this young and severely ill group of patients.