Revised curriculum on cardiothoracic radiology for diagnostic radiology residency with goals and objectives related to general competencies

This document is a revision of a previously published cardiothoracic curriculum for diagnostic radiology residency, and reflects interval changes in the clinical practice of cardiothoracic radiology and changes in the Accreditation Council for Graduate Medical Education (ACGME) requirements for diagnostic radiology training programs. The revised ACGME Program Requirements for Residency Education in Diagnostic Radiology went into effect December 2003.     

Mechanism of atrial flutter occurring late after orthotopic heart transplantation with atrio-atrial anastomosis

OBJECTIVE: We sought to better define the electrophysiologic mechanism of atrial flutter in patients after heart transplantation. BACKGROUND: Atrial flutter is a recognized problem in the post-cardiac transplant population. The electrophysiologic basis of atrial flutter in this patient population is not completely understood. METHODS: Six patients with cardiac allografts and symptoms related to recurrent atrial flutter underwent diagnostic electrophysiologic study with electroanatomic mapping and radiofrequency catheter ablation. Comparison was made with a control non-transplant population of 11 patients with typical counterclockwise right atrial flutter. RESULTS: In each case, mapping showed typical counterclockwise activation of the donor-derived portion of the right atrium, with concealed entrainment shown upon pacing in the cavotricuspid isthmus (CTI). The anastomotic suture line of the atrio-atrial anastomosis formed the posterior barrier of the reentrant circuit. Ablation of the electrically active, donor-derived portion of the CTI was sufficient to terminate atrial flutter and render it noninducible. Comparison with the control population showed that the electrically active portion of the CTI was significantly shorter in patients with transplant-associated flutter and that ablation was accomplished with the same or fewer radiofrequency lesions. CONCLUSIONS: Atrial flutter in cardiac transplant recipients is a form of typical counterclockwise, isthmus-dependent flutter in which the atrio-atrial anastomotic suture line forms the posterior barrier of the reentrant circuit. Ablation in the donor-derived portion of the CTI is sufficient to create bidirectional conduction block and eliminate this arrhythmia. Ablation or surgical division of the donor CTI at the time of transplantation could prevent this arrhythmia.     

Quantification of flow dynamics in congenital heart disease: applications of velocity-encoded cine MR imaging.

Velocity-encoded cine (VEC) magnetic resonance (MR) imaging is a valuable technique for quantitative assessment of flow dynamics in congenital heart disease (CHD). VEC MR imaging has a variety of clinical applications, including the measurement of collateral flow and pressure gradients in coarctation of the aorta, differentiation of blood flow in the left and right pulmonary arteries, quantification of shunts, and evaluation of valvular regurgitation and stenosis. After surgical repair of CHD, VEC MR imaging can be used to monitor conduit blood flow, stenosis, and flow dynamics. There are some pitfalls that can occur in VEC MR imaging. These include potential underestimation of velocity and flow, aliasing, inadequate depiction of very small vessels, and possible errors in pressure gradient measurements. Nevertheless, VEC MR imaging is a valuable tool for preoperative planning and postoperative monitoring in patients with CHD.     

A comparative study of reducing the extracellular potassium concentration in red blood cells by washing and by reduction of additive solution

BACKGROUND: Extracellular potassium concentration (K(+)) increases in the supernatant of whole and packed red blood cell units (pRBCs) with duration of refrigerated storage in citrate-phosphate-dextrose-adenine (CPDA-1) and additive solution (AS). Studies have shown that to avoid hyperkalemia, washed pRBCs are preferred if relatively fresh pRBCs are not available. To determine whether a simpler procedure, AS reduction, results in lowering of K(+) in pRBCs comparable to that achieved by washing, the K(+) levels by both methods were compared. STUDY DESIGN AND METHODS: Pre- and post-K(+) levels were measured in 6 washed and 11 AS-reduced pRBC units. Each unit was weighed, hematocrit was determined, K(+) was measured, and total K(+) was calculated. Washed units were 3 to 21 and AS-reduced units were 4 to 30 days old. Statistical analysis was performed with a t test. RESULTS: There was no significant difference (p > 0.35) in the initial K(+) between the two groups (mean +/- SD, 36.95 +/- 13.16 mEq/L before washing and 39.78 +/- 19.94 mEq/L before AS reduction). Washing and AS reduction both led to a significant decrease in K(+) levels (2.15 +/- 0.10 mEq/L after washing and 4.41 +/- 3.04 mEq/L after AS reduction, each p < 0.0005). Washing, however, was significantly better than AS reduction in reducing K(+) in stored pRBCs (p < 0.05). CONCLUSIONS: Washing pRBCs results in very low levels of K(+). AS reduction also significantly reduces K(+) levels. Selection of the method of K(+) reduction will depend on the stringency of K(+) reduction needed, the time constraints, and the availability of facilities and staff for washing.     

Patient safety in the context of neonatal intensive care: research and educational opportunities

Case reports and observational studies continue to report adverse events from medical errors. However, despite considerable attention to patient safety in the popular media, this topic is not a regular component of medical education, and much research needs to be carried out to understand the causes, consequences, and prevention of healthcare-related adverse events during neonatal intensive care. To address the knowledge gaps and to formulate a research and educational agenda in neonatology, the Eunice Kennedy Shriver National Institute of Child Health and Human Development invited a panel of experts to a workshop in August 2010. Patient safety issues discussed were the reasons for errors, including systems design, working conditions, and worker fatigue; a need to develop a "culture" of patient safety; the role of electronic medical records, information technology, and simulators in reducing errors; error disclosure practices; medicolegal concerns; and educational needs. Specific neonatology-related topics discussed were errors during resuscitation, mechanical ventilation, and performance of invasive procedures; medication errors including those associated with milk feedings; diagnostic errors; and misidentification of patients. This article provides an executive summary of the workshop.     

Upper Limb Neural Tension and Seated Slump Tests: The False Positive Rate among Healthy Young Adults without Cervical or Lumbar Symptoms

This study examined the false positive rate of the upper limb neural tension test (ULNTT) and seated slump test (SST) among healthy young adults with no history of cervical, lumbar, or peripheral symptoms. Eighty-four subjects (27 men and 57 women) with a mean age of 22.9 years participated in the investigation. All participants completed a screening questionnaire designed to exclude subjects with a history of cervical or lumbar spine pain or injury, or upper or lower extremity neurological symptoms. The ULNTT and the SST were performed on the left upper and lower extremity of each participant. Of the 84 participants tested, 73 (86.9%) were found to have a positive ULNTT at some point in the available range of elbow extension. Twenty-eight (33.3%) of the 84 subjects had a positive SST at some point in the available range of knee extension. The mean knee extension angle for those subjects with a positive SST was 15.1° with a 95% confidence interval (CI) of 12.3 and 19.7°. The mean elbow extension angle for those with a positive ULNTT was 49.4° with a 95% CI of 44.8 and 54.0°. The number of positive tests for both the ULNTT and the SST was found to be high in this sample of asymptomatic healthy young adults. Based on the results of this investigation, the authors suggest that the current criteria for determining a positive test for both the ULNTT and the SST should be examined using the proposed range of motion cut-off scores.Key Words: Neural Tension Testing, Neurodynamics, Radiculopathy, Test ValidityPhysical therapists and other healthcare providers use neural tension tests (neurodynamic tests) as part of the clinical examination to help differentiate the underlying pathoanatomic structures^1–7. The most common neural tension tests include the straight leg raise test (SLR), the seated slump test (SST), and the upper limb neural tension test (ULNTT)^1–7. The advancement of neural tension testing, particularly the SST and ULNTT, is credited to Butler^1,2, Elvey³, Shacklock^6,7, and Maitland^5,8,9. Today, neural tension testing has become a ubiquitous part of the orthopedic physical therapy examination. Despite numerous publications and the common use of these tests, there is relatively little scientific evidence available to support the diagnostic accuracy of these tests⁶.Several investigations have shown that a combination of specific body movements can create tension and gliding of neural tissues within the confines of the musculoskeletal system^10,11. If a nerve or nerve root becomes inflamed or damaged by chemical mediators, macroscopic or microscopic trauma, or entrapment, normal functional movements can produce or exacerbate neural mediated signs or symptoms^1,3,11–13. Chronic repetitive compression or traction can result in both intraneural and extraneural pathology^1,12. Nerve injury of this type is often manifested by sensory changes such as paresthesias and neurological signs such as motor weakness; and altered deep tendon reflexes can result from prolonged neural insult^11–13. Therefore, neural tension testing that places mechanical tension on the nervous system has the potential to serve as a useful clinical test to help differentiate between neural and non-neural anatomic structures^1,4,6,12.There are three common upper limb tension tests that assess neural tissues originating from the C5 to T1 nerve roots^1,4. The most commonly used ULNTT has been defined as (ULNTT 1) and is thought to emphasize tension on the median nerve^1,2,6,14. This test consists of a combination of scapular depression, shoulder abduction and external rotation, elbow extension, forearm supination, wrist and finger extension, and cervical lateral flexion first away from the tested extremity and then toward the tested extremity^1,2. Although the literature is not consistent, the ULNTT is often considered positive when there is a production of neural-mediated symptoms during elbow extension, and reduction of symptoms or an increase in elbow extension when the cervical spine is laterally flexed toward the involved extremity^1,2. This last maneuver is referred to as structural differentiation and is used to differentiate a neurodynamic response from a musculoskeletal response⁶.Shacklock⁶ stated that a musculoskeletal response (symptoms, range of motion, or resistance to movement) remains constant during differentiation, while a neurodynamic response is present when the symptoms, range of motion, or resistance to movement changes during structural differentiation. According to Shacklock, an overt abnormal neurodynamic response requires positive structural differentiation and reproduction of the patient''s symptoms⁶.Sandmark and Nisell¹⁵ determined that the ULNTT 1 has a sensitivity of 0.77 and a specificity of 0.94 in a sample of patients with neck pain. The intra-tester reliability of the ULNTT 1 in asymptomatic subjects has been reported to be 0.98^16,17. Hines et al¹⁸ reported poor inter-tester reliability when assessing resistance to movement rather than patient response based on structural differentiation.The SST is thought to examine the sensitivity of neural structures including meningeal tissues, nerve roots, and the sciatic and tibial nerves^4,5. The SST involves the patient sitting on the edge of the examination plinth in a slumped or slouched position (flexion of the thoracic and lumbar spine and a posterior pelvic tilt), flexion of the cervical spine with gentle manual overpressure, and passive extension of the subject''s knee, while the ankle is dorsiflexed. This sequence is referred to as ST1 by Butler¹. A positive test again requires structural differentiation by noting a change in symptoms, range of motion, or resistance when the cervical spine is extended and that reproduces the patient''s symptoms⁶.In a study examining patients with suspected herniated nucleus pulposus, Stankovic et al¹⁹ found the diagnostic sensitivity of the SST to be 0.83 and the specificity to be 0.55. Additionally, a study performed by Gabbe et al²⁰ found the intra-rater reliability using ICC_(3,1) as 0.95 and 0.80, while the inter-rater reliability was found as 0.92 using ICC_(2,1). Philip and Lew²¹ found strong agreement among physical therapists (Kappa = 0.89) when defining a positive test as reduction of symptoms and increased knee ROM upon cervical extension.As stated previously, several modifications have been proposed for both the SST and the ULNTT; thus, there is not a universally accepted procedure for either test^1,5. One suggested modification is to have proximal or distal initiation of the testing sequence⁶. In the distal-initiated SST, the subject''s ankle is dorsiflexed first for pretension of the sciatic and tibial nerves. In the proximal-initiated test, the subject is asked to flex the cervical spine first for pretension of the dura. A second alteration of the SST is to have the subject axially rotate the thoracic spine²². The order in which the test is performed is believed to influence the direction of neural glide but it may also affect symptom reproduction⁶.Clinical observation and experience teaching neural tension testing for many years led the present investigators to observe that many asymptomatic subjects without frank cervical, lumbar, or peripheral symptoms present with neural-mediated symptoms and positive structural differentiation when full-range testing of the SST and ULNTT is performed. Thus, clinical observation indicated that there might be an unusually high false positive rate among these tests when performing full-range testing of the elbow (ULNTT) and the knee (SST). Shacklock⁶ referred to the production of neural-mediated symptoms among asymptomatic subjects as a normal positive test and suggested reproduction of the patient''s symptoms should be an integral part of the diagnostic criteria. It should be noted that reproduction of symptoms is impossible in asymptomatic subjects (no pathology); therefore, this criteria cannot be used when examining the rate of false positive tests. Therefore, the purpose of this investigation was to determine the false positive rate of the SST and ULNTT in otherwise healthy young adults without cervical, lumbar, or peripheral symptoms and to identify possible cut-off scores based on knee (SST) and elbow (ULNTT) range of motion.