Total white blood cell (WBC) and neutrophil counts are lower among individuals of African descent due to the common African-derived "null" variant of the Duffy Antigen Receptor for Chemokines (DARC) ...gene. Additional common genetic polymorphisms were recently associated with total WBC and WBC sub-type levels in European and Japanese populations. No additional loci that account for WBC variability have been identified in African Americans. In order to address this, we performed a large genome-wide association study (GWAS) of total WBC and cell subtype counts in 16,388 African-American participants from 7 population-based cohorts available in the Continental Origins and Genetic Epidemiology Network. In addition to the DARC locus on chromosome 1q23, we identified two other regions (chromosomes 4q13 and 16q22) associated with WBC in African Americans (P<2.5×10-8). The lead SNP (rs9131) on chromosome 4q13 is located in the CXCL2 gene, which encodes a chemotactic cytokine for polymorphonuclear leukocytes. Independent evidence of the novel CXCL2 association with WBC was present in 3,551 Hispanic Americans, 14,767 Japanese, and 19,509 European Americans. The index SNP (rs12149261) on chromosome 16q22 associated with WBC count is located in a large inter-chromosomal segmental duplication encompassing part of the hydrocephalus inducing homolog (HYDIN) gene. We demonstrate that the chromosome 16q22 association finding is most likely due to a genotyping artifact as a consequence of sequence similarity between duplicated regions on chromosomes 16q22 and 1q21. Among the WBC loci recently identified in European or Japanese populations, replication was observed in our African-American meta-analysis for rs445 of CDK6 on chromosome 7q21 and rs4065321 of PSMD3-CSF3 region on chromosome 17q21. In summary, the CXCL2, CDK6, and PSMD3-CSF3 regions are associated with WBC count in African American and other populations. We also demonstrate that large inter-chromosomal duplications can result in false positive associations in GWAS.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The diagnosis of coronary aneurysms has already been described using transthoracic and transesophageal echocardiography. In the present report we demonstrated the use of real-time three-dimensional ...echocardiography for the diagnosis of a large left circumflex coronary aneurysm. The improved spatial resolution of this new imaging technique provided valuable information for anatomic characterization of the coronary aneurysm, allowing for distinction between the lumen and lining thrombus. The findings were confirmed by magnetic resonance imaging and coronary angiography.
OBJETIVO: Avaliar o valor do ecocardiograma Doppler(ECO) transtorácico na identificação de perviabilidade da anastomose entre artéria torácica interna esquerda (ATIE) e interventricular anterior, ...realizada pela técnica de revascularização miocárdica pela minitoracotomia sem circulação extracorpórea. MÉTODOS: Estudaram-se os primeiros 12 pacientes, consecutivos, no período de pós-operatório intra-hospitalar pelo ECO, utilizando-se transdutores de 5MHz, pela via paraesternal esquerda, preferencialmente. Foram analisadas velocidades máximas e integrais de velocidade dos componentes sistólico e diastólico das curvas espectrais de fluxo Doppler. Todos pacientes foram submetidos à cinecoronariografia, enquanto hospitalizados. RESULTADOS: O ECO foi exeqüível em 93% dos pacientes. Nos com anastomose pérvia (6/7), observou-se ao estudo Doppler amplo componente diastólico (padrão A). Naqueles com anastomose obstruída (4/4) o padrão observado foi de predomínio sistólico (padrão B) (p=0,003*). CONCLUSÃO: O ECO da ATIE anastomosada com a artéria interventricular anterior, após cirurgia de revascularização miocárdica pela técnica de minitoracotomia, permitiu caracterizar precocemente, com precisão, a perviabilidade da anastomose.PURPOSE: To study the value of Doppler echocardiography as a tool for the evaluation of left internal thoracic artery graft (LITAG) patency in patients who underwent coronary revascularization using minimally invasive bypass surgery without extracorporeal circulation. METHODS: The first 12 consecutive patients were studied after coronary artery bypass surgery using a 5MHz Doppler transducer. Doppler signals for the systolic and diastolic flow velocities were preferably obtained in the second intercostal space. All patients underwent coronary angiography while hospitalized. RESULTS: The exam was feasible in 93% of patients. Doppler flow pattern was predominantly diastolic (pattern A) in patients with patent anastomoses (6/7). In patients with occluded anastomoses (4/4) Doppler flow pattern was predominantly systolic (pattern B) (p=0.003). CONCLUSION: Internal thoracic artery flow pattern as measured by Doppler echocardiography after minimally invasive coronary artery bypass graft surgery is an accurate method for identifying LITAG patency.
OBJETIVO: Tendência atual em todas as áreas da cirurgia aponta para táticas e técnicas cirúrgicas que tornem o ato operatório cada vez menos invasivo. O objetivo do presente estudo foi avaliar a ...viabilidade da revascularização do miocárdio através de mínima incisão torácica (minitoracotomia esquerda), sem circulação extracorpórea. CASUÍSTICA E MÉTODOS: De setembro de 1995 a março de 1996, um total de 19 pacientes portadores de lesões isoladas do ramo interventricular anterior (RIA) e/ou diagonal (Dg) foram submetidos a revascularização do miocárdio, tendo, como via de acesso, toracotomia anterior paraesternal esquerda, de aproximadamente 7 cm de extensão, ao nível do 4º espaço intercostal. Através dessa incisão foi dissecada a artéria torácica interna esquerda (ATIE) em extensão suficiente para a realização da anastomose com o RIA efetuada sem circulação extracorpórea. No 2º dia de pós-operatório esses pacientes foram submetidos a arteriografia e eco-Doppler transtorácico da ATIE para verificação das condições do enxerto e da persistência de fluxo pelos ramos intercostais não ligados por ocasião da dissecção parcial da artéria. RESULTADOS: Todos os pacientes tiveram boa evolução pós-operatória. O resultado da ATIE realizado em 16 dos 19 pacientes operados mostrou padrões angiográficos excelentes em 13 deles. Não se demonstrou contrastação dos ramos intercostais não ligados durante a dissecção. O Doppler transtorácico se correlacionou com as condições dos enxertos. CONCLUSÃO: Os resultados iniciais obtidos na revascularização do miocárdio através de minitoracotomia esquerda sugerem ser esta uma boa alternativa tática para portadores de lesão isolada do RIA com excelente resultado estético.There is a tendency in all fields of surgery to move towards less invasive surgical techniques in recent years. The end point of this study was to analyse the possibility of myocardial revascularization through a minimum left thoracotomy approach. From September 1995 till March 1996 we operated on 19 patients that had isolated lesion of interventricular anterior artery (IAA) and/or diagonal. The anastomoses were made by a left minor thoracotomy, opening the pleura at the 4º intercostal space. Through this incision we dissected the thoracic internal artery with ligation of only few branches. The anastomoses were performed without extracorporeal circulation, with a simple interruption of coronary blood flow. At the second postoperative day we studied the patients with angiography and transthoracic echo-Doppler, to verify patency and flow. All patients had uneventful recovery without major complications. Angiography was made in 16 out of 19 and showed patency in 13. The 3 patients with graft occlusion were reoperated on without complications. The presented technique did not involve ligation of the intercostal branches, however these branches were not demonstrated by angiography. Transthoracic Doppler showed good relationship with angiographic findings. The initial results with this technique suggest that we can have another option of minimum invasive myocardial revascularization for selected patients.
To characterize Doppler flow patterns of the grafted left internal mammary artery (LIMA) in patients with and without dobutamine stress induced wall motion abnormalities in the graft distribution, we ...studied 29 patients who underwent coronary artery bypass surgery using LIMA grafts to the left anterior descending coronary artery (LAD). The ungrafted right internal mammary artery (RIMA) was used as a control. RIMA Doppler flow pattern was predominantly systolic in all patients. In patients without ischemia in the LAD distribution, LIMA flow was predominantly diastolic. In patients with ischemia, LIMA flow was predominantly systolic. In the grafted LIMA, a ratio of diastolic to systolic time-velocity integral of >1.5 best showed absence of ischemia in the graft distribution. In summary, characterization of the Doppler flow pattern in the internal mammary arteries is feasible. In the grafted LIMA, ratios of diastolic to systolic flow are less in patients with an ischemic response in the subtended vascular bed than in those without ischemia.
Objectives. We sought to assess whether the site of future myocardial infarction can be predicted on the basis of induced dyssynergy (“area at risk”) recognized by stress echocardiography.
...Background. The severity and extent of stress-induced dyssynergy are strong predictors of subsequent major cardiac events. However, high grade stenotic lesions are not strictly associated with the site of future coronary occlusions.
Methods. From the stress echocardiography multicenter trials data bank, we selected 70 patients (56 men; mean age ± SD 58 ± 11 years) meeting the following inclusion criteria: 1) dipyridamole (n = 53) or dobutamine (n = 17) stress echocardiography; 2) a spontaneously occurring infarction, with no intercurrent revascularization procedure between the initial study and the infarction; and 3) a follow-up rest echocardiogram obtained 41 ± 90 days after the infarction.
Results. A complete ischemia-infarction mismatch (infarct-related dysfunction in a patient with negative stress test results) occurred in 29 patients (41%). A partial mismatch (ischemic dysfunction in a territory different from the infarct area) occurred in nine patients (13%). A match (ischemia-related and infarction-related dyssynergy involving the same region) occurred in 32 patients (46%). The average time interval between the stress examination and the occurrence of infarction or reinfarction was 144 ± 160 days in patients with a match and 439 ± 622 days in patients with a mismatch (p < 0.05).
Conclusions. Induced ischemia (imaged as transient dyssynergy by pharmacologic stress echocardiography) inconsistently identifies the site of future infarction. The majority of spontaneous coronary occlusions leading to infarction unheralded by induced ischemia. However, most infarctions occurring within 1 year of stress testing are in the area identified as ischemic during testing.
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