[Rare Dorsal Traumatic Sternoclavicular Joint Dislocation in a 14-Year-Old Patient - a Case Report]. / Raritní dorzální traumatická luxace sternoklavikulárního kloubu u ctrnáctiletého pacienta ­ kazuistika.

We report a case of a 14-year-old patient with rare dorsal sternoclavicular dislocation caused by a sports injury. The patient was admitted to our department for further investigation and treatment. After a series of examinations, an open reduction and fixation using K-wires was used as a treatment modality. A satisfactory outcome was achieved, the patient returned to full sports activity 3 months after the surgery, with no limitations of movement. The necessity of early diagnosis and treatment options of this rare injury has been discussed. Key words: sternoclavicular joint, dorsal dislocation, open reduction.

[Minimal Invasive Fixation of Pelvic Injury: CT-Study of the Pelvic Bone Dimensions]. / Miniinvazivní osteosyntéza poranení pánve: CT studie rozmeru skeletu pánve.

UNLABELLED: PURPOSE OF THE STUDY This radiographic study was focused on measuring the dimensions of pelvic bones at sites of minimally invasive screw insertion with the aim to assess the risk of damage to vascular and nervous structures. MATERIAL AND METHODS The group consisted of 77 patients (39 women and 38 men) aged between 19 and 85 years (average, 65; women, 65; men, 64) who underwent CT examination of the pelvis because of reasons other than injury. On the left side, a total of 14 dimensions of the superior pubic ramus, supraacetabular region, retroacetabular region, quadrilateral surface of the acetabulum and lateral foraminal sides of the S1 and S2 vertebral bodies were measured. The results were evaluated using descriptive statistics. RESULTS The inner antero-posterior dimension of the isthmic area of the superior pubic ramus was 8 mm or less in four women (10.3%) and 9 or 10 mm in further 14 women (35.9%). The inner cranio-caudal dimension of the superior pubic ramus was 8 mm or less in 14 women (35.9%) and 9 or 10 mm in further 16 women (41.0%). These dimensions obtained in men were as follows: 8 mm and less in three men (7.9%) (7 mm in one, 8 mm in two), and 9 or 10 mm in nine men. Sizes of the other pelvic bones were large enough to allow for safe insertion of single screws. DISCUSSION Single screws most frequently used in minimally invasive treatment of pelvic fractures are cannulated screws 7.3 mm or 6.5 mm in diameter; less frequently used are 4.5-mm cancellous screws (e.g. in treatment of avulsion injuries) or long 3.5-mm cortical "creeping" screws to be inserted in the superior pubic ramus. The use of "creeping" screws reported by several authors indicates problems associated with placement of standard screws (diameter, 7.3 mm and 6.5 mm) through the isthmus into the superior ramus. In slim high pelvises of some patients with gracile skeletons or in low pelvises of small women, the screws can protrude over the cortical margin. However, the risk of injury to nervous or vascular structures is low when the intraosseous screw is exactly inserted and it is so even in case its thread cuts into cortical bone. Neither the femoral artery nor the femoral nerve is situated too close to the superior pubic ramus. The "corona mortis" may potentially be jeopardised because of its contact with both the superior and posterior cortical bones of the superior ramus, but it usually follows a course more lateral to the isthmus of the ramus. CONCLUSIONS The results of the study showed that the size of the superior pubic ramus in its isthmic area may cause difficulties during insertion of cannulated screws with standard diameters (7.3 mm and 6.5 mm) in the majority of women and in some men. The risk of damage to vascular and nervous structures during screw insertion is associated only with the superior and posterior walls of the superior pubic ramus and with the area of the S2 foramen in case the correct procedure of intraosseous screw insertion is not strictly followed. KEY WORDS: retrograde pubic screw, iliosacral screw, supraacetabular screw, retrograde posterior column screw.

[Treatment of Keratoconus with Corneal Cross-linking--Results and Complications in 2 Years Follow-up]. / Corneal cross-linking v liecbe keratokónusu--výsledky a komplikácie v dvojrocnom sledovaní.

OBJECTIVE: The objective of the study was to assessment of changes of monitored parameters after CXL. Incidence of complications were assessed in the whole group and in groups of patients divided according to the selected criteria. Evaluated parameters were also relations between them and in time. METHODS: The 86 eyes of patients with progressive keratoconus who underwent CXL according to the Dresden protocol in the years 2007-2009 at the Ophthalmic clinic FN Brno Bohunice were included in this study. RESULTS: There was observed significant increase of BCVA (letters--before CXL 42,30±10,35, 1st year after CXL (1Y) 44,68±10,04, p<0,01, 2nd year after CXL (2Y) 44,44±10,57, p<0,01) and SE (-5,95±3,98D, -5,27±3,84D, p<0,01, -4,94±3,68D, p<0,01), and decrease of maximum curvature of the cornea (MAX--before CXL 50,39±4,17D, 1Y 49,46±4,13D, p<0,01, 2Y 49,42±4,14D, p<0,01). Change of ultrasound CCT, polymegatisms, pleomorfisms and corneal endothelial cell density was not significant. The value of MAX is the most important parameter in estimating the effect of CXL. The highest incidence of corneal opacity after CXL was observed in the eyes of patients with III. stage of keratoconus over 40 years old, carrying hard contact lenses and with biomikroskopic symptom of keratoconus on the cornea. We found that corneal thickness measurement with Orbscan II and the mesurement of IOP with noncontact method is incorrect by patients after CXL. CONCLUSION: Corneal cross-linking of the cornea is safe and effective procedure of stopping the progression of keratoconus in 97% of eyes in the period up to 2 years after CXL.

[The effectiveness of corneal cross-linking in stopping the progression of keratoconus]. / Efektivita corneal cross-linkingu v zastavení progresie keratokónusu.

OBJECTIVE: Objective of the study was to prove the efficiency of corneal cross-linking (CXL) in stopping the progression of keratoconus. METHODS: In this study were included 58 eyes of patients with progressive keratoconus who underwent CXL according to the Dresden protocol in the years 2007-2009 at the Ophthalmic clinic FN Brno Bohunice. The eyes of patients were divided into four groups according to the change of maximum curvature of the cornea two years after CXL. RESULTS: Stabilization of maximum curvature of the cornea have been reported in 40 % of eyes, regression in 57 % of eyes by an average of 1,92D and disease progression in 3 % of eyes 2 years after CXL. The eyes with regression over 2D had significantly higher best-corrected visual acuity before and after the procedure compared to the group with stabilization. Spherical equivalent increased significantly in all groups, on average, in the group with stabilization of 0,54D, in the group with mild regression of 0,71D and in the group with a large regression of 2,09D. In the group with a large regression 100 % of eyes had stabilization or increase in SE. Our observations showed that, when a decrease in the patient keratometric values of cornea is present after CXL, it is comprehensive and applies to all parameters. CONCLUSION: We have confirmed that corneal cross-linking stops the progression of the disease in 97 % of eyes two years after the procedure.

[Corneal cross-linking--modern method of keratoconus treatment]. / Corneal cross-linking--moderná metóda liecby keratokónusu.

PURPOSE: The aim of research study was to evaluate the effect of corneal cross-linking (CXL) in the frame of patients with progressive keratoconus 1 year after treatment. METHODS: There were 40 eyes of 35 patients with mean age 28, 45 +/- 9.3 (SD) (15 to 48 years) included in the study. Patients were treated with standard protocol of CXL with abrasion of corneal epithelium. Complete ophthalmological examination included best corrected spectacles visual acuity (BCSVA), slit-lamp microscopic finding, corneal topography and corneal thickness measured with ultrasound method was performed before, on the 5-th day, 1. 6., 12. month after CXL. We divided patients according to the stage of keratoconus into 2 groups (stage I. and stage II.) and according to the age into 3 groups (until 20, from 21 to 39, over 40 years). RESULTS: In all treated eyes, the CXL was without relevant complications. The only complication was stromal haze of cornea. In the evaluation based on stage of keratoconus, in the first group any patient became a haze of cornea in 1 year after CXL. In the second group 35.7% of patients had a haze of cornea. The average BCSVA 1 year after treatment was improved in the 1. group about 5.38 letter and in the 2. group about 1.25 letter. Topographic analysis showed decrease of simulated keratometry and refraction (1. group--0.1 D, 2. group--0.17 D), maximal keratometry and refraction (1. group--0.67 D, 2. group--0.76 D). Minimal keratometry and refraction in the 1. group decreased (1.17 D) and increased in the 2. group (1.09 D). In the evaluation based on the age was haze monitored in the first group one year after CXL in 12.5% of researched eyes. In the second group was haze of cornea in 20% of eyes and in the third group consisting of patients over 40 years old, in 50% of eyes. The average BCSVA was improved in the 1. group (2.85 letter), and in the 2. group (3.68 letter).The average BCSVA was decreased in the oldest patients in about 1.43 letter. In the 1. and 2. group the topographic analysis showed decrease of simulated keratometry and refraction (1. group--0.12D, 2. group--0.21D), maximal keratometry and refraction (1. group--1.13 D, 2. group--0,68D), minimal keratometry and refraction (1. group--1.17D, 2. group--0,69 D). In the 3. group the topography analysis showed increase of simulated keratometry and refraction (0,8D), maximal keratometry and refraction (0,98D), minimal keratometry and refraction (0,28D). Corneal pachymetry remained stable in all researched groups of patients. CONCLUSIONS: CXL is considered as safe procedure to stop progression of keratoconus also for patients until 19 years old. The best effect and minimal complications were by patients until 40 years old and by patients with the I. grade.

[Contrast sensitivity and higher order aberration after conventional LASIK treatment]. / Kontrastní citlivost a aberace vyssích rádu po konvencním LASIKu.

AIM: The aim of the prospective study was to evaluate photopic high-contrast visual acuity, mesopic contrast sensitivity, and high order aberrations, to compare changes and post-operative development of those parameters and to analyze the dependence among aberrations and contrast sensitivity after conventional LASIK treatment. MATERIALS AND METHODS: The authors followed-up patients treated by means of refractive LASIK treatment during the period from November 2006 to November 2007. The authors analyzed 51 eyes (31 patients). The average age of the group was 28.5 +/- 5.4 years (range, 18 - 41 years), preoperative average spherical equivalent was -4.95 +/- 1.24 D (from -3 to -8,25 D). Before the treatment and 1, 3, 6, and 12 months after LASIK treatment we evaluated the visual acuity (Snellen optotypes), contrast sensitivity under mesopic circumstances (CSV-1000E, VectorVision) and monochromatic aberrations (aberometer Zywave, Bausch & Lomb). RESULTS: One year after the treatment the average uncorrected visual acuity was 1.07 +/- 0.15, index of effectiveness 0.99, and index of safety 1.02. The contrast sensitivity was in month 12 significantly decreased comparing to the preoperative level at the frequency 12 c/deg, in other already tested frequencies after 3-6 moths did not differed from preoperative values. During the follow-up period the curvature of contrast sensitivity average values was in the upper half of the normal interval range. Conventional LASIK treatment significantly induced the higher order aberration (twice), as well as the spherical aberration (four times).The same level of higher order aberrations root mean square (HOA-RMS), or increased maximally by 0.1 microm was detected by 10 % of cases; the spherical aberration was, compared to the preoperative value, lower, or increased maximally by 0.05 microm in almost one half of the cases. The increase of the higher order aberrations depended directly proportionally to the preoperative value of the spherical equivalent. Before the treatment, the values of total aberrations correlated to the contrast sensitivity of low space frequencies; however, there was not found any correlation between the higher order aberrations and contrast sensitivity. Six months after the LASIK treatment the values of higher order aberrations correlated to the contrast sensitivity except of the lowest frequency tested. The higher order aberrations increased together with decreasing contrast sensitivity. The data from the one-year follow up control did not show statistically significant correlation between the contrast sensitivity and the higher order aberrations. There was not found any correlation between the contrast sensitivity and the spherical aberration at any follow-up control after the surgery. CONCLUSION: Although after the conventional LASIK treatment the curve of mesopic contrast sensitivity was located in the upper half of the normal range, in the medial space frequency it remained decreased comparing to the preoperative stage. The induction of higher order aberrations was twice as much and was directly correlated to the degree of the laser correction. The spherical aberration was four-times higher comparing to the preoperative values and was independent to the level of the initial refractive error. Significant correlation between the contrast sensitivity and the higher order aberrations was not proven.

[Changes of higher order aberrations and contrast sensitivity after standard photorefractive keratectomy]. / Zmeny aberací vyssích rádu a kontrastní citlivosti po standardní fotorefrakcní keratektomii.

UNLABELLED: The aim of the prospective study was to evaluate higher order aberrations and contrast sensitivity after photorefractive keratectomy (PRK) using the standard photoablation profile. MATERIALS AND METHODS: The group consisted of 37 patients (69 eyes), the mean age 27.2 +/- 4.5 years, who underwent PRK with target emetropia during the period January 2007 -December 2007. In 19 cases, it was correction of myopia, in 50 cases myopia with astigmatism.The preoperative spherical equivalent was -3.14 +/- 0.95 D. The PRK was performed by means of excimer laser system Technolas 217 (Bausch & Lomb) with the standard phoptoablation profile (PlanoScan 2000), using the 6.5 mm optical zone. The visual acuity, contrast sensitivity (CS; CSV-1000E, VectorVision) under mesopic circumstances and monochromatic aberrations (Zywave, Bausch & Lomb) were evaluated before the surgery, and 1,3, 6, and 12 months thereafter. The pair t-test, Wilcoxon test, and the Mann - Whitney U test (alpha = 0.05) were used for the statistical analysis. RESULTS: The PRK showed high index of effectiveness and safety (0.98, respectively 1.03 in the first year after the procedure). The contrast sensitivity under mesopic circumstances was not significantly involved after the PRK. The main value of the CS remained during the whole follow-up period within the physiological range in all spatial frequencies. Postoperatively, the part of spherical aberration on the higher order aberrations increased from 13.1% preoperatively to 16.6% one year after the PRK. In one half of the cases, the change of the higher order aberrations was within the range +/- 0.1 microm. In 66% of cases, the change of the spherical aberration was +/- 0.05 microm. The higher order aberrations comparing to the preoperative values decreased or remained unchanged approximately in one third of the cases, and the spherical aberration in one quarter of the cases. There was not established dependence between monochromatic aberrations values and the contrast sensitivity. CONCLUSION: Although the conventional RPK for low myopia treatment induces higher order aberrations including the spherical aberration, the impact on the contrast sensitivity under mesopic circumstances in our group were not significant. The contrast sensitivity of the most of patients was near the upper limit of the normal range.

Primary mediastinal pleomorphic rhabdomyosarcoma: a case report.

OBJECTIVE: To report a rare case of pleomorphic rhabdomyosarcoma which occurred in the mediastinum of a 34-year-old man. CLINICAL PRESENTATION AND INTERVENTION: A young male labourer presented with dyspnoea on exertion. A large mediastinal mass was detected on chest CT scan. The chest surgeons advised against open biopsy. His alpha-fetoprotein was 22,000 IU/l; based on this the diagnosis of a germ cell tumour was made and the patient was treated with a bleomycin/etoposide/cisplatin regimen. He left for his native country where an open biopsy from the mediastinum was taken and reported as pleomorphic rhabdomyosarcoma. He was given five courses of chemotherapy with doxorubicin, etoposide, and ifosfamide with mesna protection without much relief. The inoperable disease occupied the whole of the right chest and mediastinum. The enormous size of the radiation field made radiotherapy prohibitive. Finally, the patient opted for symptomatic treatment and left for his native place. CONCLUSION: This case is presented because of its difficulty in management and rarity.

[Calculation of diopter value of the IOL in simultaneous cataract surgery and perforating keratoplasty]. / Výpocet dioptrické hodnoty IOL pri soucasne provedené operaci katarakty a perforující keratoplastice.

PURPOSE: To evaluate the successfulness of intraocular lens (IOL) power calculation and refractive error after the triple procedure. METHODS: During the period 1995-2004, the triple procedure was performed in 51 eyes of 43 patients aged 29-83 years (mean 66 years) with corneal disease and cataract. For the IOL power calculation, the SRK II formula was used. In case of impossibility to measure the keratometry, the data from the other eye, or the value 7.7 mm were used. The donor cornea was punched by trephine with the diameter 0.50 mm (in 88.2% of eyes) or 0.25 mm (in 11.8% of eyes) larger than for the recipient cornea. In 30 eyes (58.8%), the interrupted suture was used, in 21 eyes (41.2%) the running suture was employed. In 33% of eyes, the PMMA IOL was implanted, in 18 eyes (35.3%) the hydrophilic acrylate IOL. The final refraction and visual acuity was evaluated 13 - 24 months (mean, 17.1 months) after the surgery, and always after the suture removal. RESULTS: The best-corrected visual acuity (BCVA) ranged 0.1 - 1.0 (mean, 0.4 +/- 0.2). BCVA 0.5 or better was achieved in 26 eyes (51.0%). The spherical equivalent of postoperative refractive error less or equal to 2 dioptres was achieved in 35 eyes (68.6%) and ranged from 0.0 to 3.6 dioptres (mean, 1.4 +/- 1.1 dioptres). CONCLUSION: According to the final refraction of the eye, the use of our method of IOL power calculation in the triple procedure is satisfying and its results are comparable with results published in the literature.

[Cardiac abnormalities of lyme borreliosis]. / Postizení srdce v prubehu lymeské borreliózy.

The article summarizes basic characteristics of Lyme borreliosis, its incidence, epidemiology, pathogenesis and clinical image. Particular attention is given to the review of papers aimed at the cardiac abnormalities--the Lyme carditis. Though they are not very frequent, due to the variability of their clinical course and due to various forms, which are difficult to diagnose, they can represent a specific problem. Major part of the article is given to the authors' own experience with the dilated cardiomyopathy of the Borrelia origin and namely to the perspective study of the patients after the skin form of the disease erythema migrans, who were treated "lege artis" in the early phase of the disease with antibiotics. Authors were interested how many of those patients would develop later the cardiac abnormalities.

Improved method of detection and molecular typing of Borrelia burgdorferi sensu lato in clinical samples by polymerase chain reaction without DNA purification.

A simple assay by polymerase chain reaction was used for the of detection of Borrelia burgdorferi, causative agent of Lyme borreliosis (LB). It involves no DNA purification and is based on the amplification of a specific region of ospA gene of B. burgdorferi, followed by direct detection of the PCR product with SYBR Green I by agarose gel electrophoresis. The method was used to analyze samples from patients with LB diagnosis, with presumable infection with the LB spirochete, those with unclear clinical symptoms and after the course of an antibiotic treatment. Spirochetal DNA was detected by PCR even in contaminated samples in which B. burgdorferi was overgrown by fungi and other bacteria. Spirochetal DNA was detected and borrelia species was identified in cerebrospinal fluid of two patients hospitalized with the diagnosis "fever of unknown origin". Western blot and ELISA were negative in both cases. Total analysis of 94 samples from the hospital in Ceské Budejovice (South Bohemia, Czechia) showed infection with B. burgdorferi sensu stricto in 11% and B. garinii in 15% of cases. The highest prevalence was found for B. afzelii (43%). Co-infection was confirmed in 24 % of the analyzed symplex; 7% of samples that were B. burgdorferi sensu lato positive gave no results in DNA amplification with B. burgdorferi sensu stricto-, B. garinii- and B. afzelii-specific primers. The proposed reliable, rapid, unexpensive and specific technique could form the basis of laboratory tests for routine detection and identification of Lyme-disease spirochete in different samples.

Screening of six risk exons of the RET proto-oncogene in families with medullary thyroid carcinoma in the Czech Republic.

Medullary thyroid carcinoma (MTC) occurs as a sporadic form (75%) or as an autosomal dominant inherited familial disorder (25%) called familial MTC (FMTC) or as multiple endocrine neoplasia type 2 (MEN2) syndromes. Germ-line mutations in the rearranged during transfection (RET) proto-oncogene in exons 10, 11, 13, 14, 15 and 16 are known to be a cause of most of the familial forms. In this paper we report molecular genetic testing of 106 families with MTC (358 tested persons) from the Czech Republic in which we directly sequenced these six exons of the RET proto-oncogene. We detected germ-line mutations in 100% of MEN2B families (4/4 families), 90% of MEN2A families (9/10), 40% of FMTC families (4/10) and 7% of apparently sporadic MTC (6/82). Eleven different germ-line mutations were revealed. MEN2B was associated with mutation Met918 Thr in exon 16. In one MEN2B family beside this mutation the Tyr791 Phe was also found, which has not yet been reported. MEN2A was restricted to different mutations in exon 11 (codon 634). In FMTC and 'sporadic' MTC families the mutations in exons 10, 11, 13 and 14 were detected. The genotype/phenotype correlations are given. Genetic testing revealed germ-line mutations in 23 index patients, 24 family members and excluded them in 53 relatives.

Hodgkin's disease: Kuwait experience.

OBJECTIVE: To describe histologic subtypes, clinical presentation and treatment outcome of Hodgkin's lymphoma in Kuwait. SUBJECTS AND METHOD: Patients older than 15 years, diagnosed with Hodgkin's lymphoma between 1980 and 1998, were included in this retrospective analysis. Data were collected using a standardized form that included demographics, histologic subtypes, clinical presentation, stage, extranodal involvement, treatment modality and follow-up. Histology reports were obtained from hospital records. RESULTS: There were 83 (59%) males and 57 (41%) females. Dominant histologic subtypes were nodular sclerosis 65 (46.4%) and mixed cellularity 42 (30%). Constitutional symptoms were reported by 54 (38.6%) of the cases. Two thirds (64%) of the cases were advanced. Primary extranodular involvement included liver (8%), gastrointestinal tract (7%), lung and bone marrow (4% each). Disease-free survival according to treatment groups were: radiotherapy alone 100%, chemotherapy alone 88%, and combined modality 65%. The 5-year Kaplan-Meier estimates of overall disease-free survival was 84%. CONCLUSION: In the cohort of 137 patients with Hodgkin's disease the treatment with combined radiotherapy and chemotherapy had a remarkable outcome. However, evaluation of long-term treatment complications is needed.

Intra-atrial conduction block along the mitral valve annulus during accessory pathway ablation: evidence for a left atrial "isthmus".

INTRODUCTION: We observed a change in the atrial activation sequence during radiofrequency (RF) energy application in patients undergoing left accessory pathway (AP) ablation. This occurred without damage to the AP and in the absence of a second AP or alternative arrhythmia mechanism. We hypothesized that block in a left atrial "isthmus" of tissue between the mitral annulus and a left inferior pulmonary vein was responsible for these findings. METHODS AND RESULTS: Electrophysiologic studies of 159 patients who underwent RF ablation of a left free-wall AP from 1995 to 1999 were reviewed. All studies with intra-atrial conduction block resulting from RF energy delivery were identified. Fluoroscopic catheter positions were reviewed. Intra-atrial conduction block was observed following RF delivery in 11 cases (6.9%). This was evidenced by a sudden change in retrograde left atrial activation sequence despite persistent and unaffected pathway conduction. In six patients, reversal of eccentric atrial excitation during orthodromic reciprocating tachycardia falsely suggested the presence of a second (septal) AP. A multipolar coronary sinus catheter in two patients directly demonstrated conduction block along the mitral annulus during tachycardia. CONCLUSION: An isthmus of conductive tissue is present in the low lateral left atrium of some individuals. Awareness of this structure may avoid misinterpretation of the electrogram during left AP ablation and may be useful in future therapies of atypical atrial flutter and fibrillation.

Congenital long QT syndromes and Brugada syndrome: the arrhythmogenic ion channel disorders.

Congenital long QT syndromes (LQTS) and Brugada syndrome are hereditary disorders of cardiac ion channels which result in life-threatening cardiac arrhythmias or sudden cardiac death in patients with anatomically normal hearts. The pathogenesis of these dramatic events has been partially elucidated with the identification of the individual ion channels involved and understanding of the effect of some disease-causing mutations on the membrane currents and action potential. The clinical spectrum of congenital LQTS is broader than previously thought and involves certain patients previously diagnosed with idiosyncratic drug-induced proarrhythmia. The initial treatment for congenital LQTS patients involves beta-blockers in most cases. Indications for implantable cardioverter-defibrillator (ICD) or pace-maker (PM) implantation in selected individuals continue to evolve.

[Therapy of thyroid carcinoma using radioiodine]. / Terapie karcinomu stítné zlázy pomocí radiojodu.

The paper is submitted as one of the recommendations for diagnostic and therapeutic care in nuclear medicine meant in particular for the clinical need of physicians indication treatment of thyroid carcinoma with iodide. The author presents a brief review of principles, indications, the procedure proper, clinical interpretation and possible risks and contraindications, incl. the clinical and socioeconomic impact.

Asymptomatic occlusion of the left main coronary artery by an aortic pseudoaneurysm.

Extrinsic compression of the left main coronary artery is a rare cause of coronary ischemia. We describe a 35-year-old Asian woman with complete asymptomatic occlusion of the left main coronary artery by a large aortic pseudoaneurysm. She underwent repair of the pseudoaneurysm and coronary artery bypass grafting at the Mayo Clinic in Rochester, Minn. The differential diagnosis is discussed. Based on this patient's age and associated vascular lesions, we conclude that Takayasu arteritis was the most likely cause of her condition.

Structure, G protein activation, and functional relevance of the cardiac G protein-gated K+ channel, IKACh.

The muscarinic-gated atrial potassium channel IKACh has been well characterized functionally, and has been an excellent model system for studying G protein/effector interactions. Complementary DNAs encoding the composite subunits of IKACh have been identified, allowing direct probing of structural and functional features of the channel. Here, we highlight recent approaches taken in our laboratory to determine the oligomeric structure of native cardiac IKACh, the mechanism of activation of IKACh by G proteins, and the relevance of IKACh to cardiac physiology.