Ítalo Martins de Oliveira

Fibrosis, myocardial crossings, disconnections, abrupt turns, and epicardial reflections: do they play an actual role in human permanent atrial fibrillation? A controlled necropsy study

Atrial myocardium fibrosis and other alterations of fiber continuity and potential circuit reentrancy (disconnections, abrupt turns, crossings, and epicardial reflections) are thought to play an important role in permanent atrial fibrillation. However, few studies have been performed in human beings. Some of them are only descriptive, and controls were usually normal hearts; thus, differences between cases and controls could be related to the underlying disease rather than the arrhythmia. We quantified by histomorphometry the above characteristics in nine samples (three from the left atrium, three from around fat pads, one from the right atrium, one from the cavum-tricuspid isthmus, and one from the ventricular septum) from 13 necropsy hearts of patients with permanent atrial fibrillation and compared the findings with those from 13 control cases with the same diseases but without any atrial arrhythmia. Statistical analysis was performed using generalized estimating equations and a normal linear mixed model for repeated measures, with significance defined as P ≤.05. No differences were found in fibrosis (estimated as collagen/(collagen+myocardium) ratio-0.26 vs. 0.23, P=.35), the presence of disconnections (70.1 vs. 61.5, P=.09), abrupt turns (43.6 vs. 45.3, P=.84), or epicardial reflections (9.4 vs. 14.5, P=.12). The only difference identified was that cases with permanent atrial fibrillation exhibited fewer crossings than those without (79.5 vs. 91.5, P=.02). In conclusion, alterations in myocardial fiber continuity, including fibrosis, seem to reflect a generalized myocardial disorganization of the atria in cardiac disease but are not specifically related to permanent atrial fibrillation.

Análise de peças anatômicas preservadas com resina de poliester para estudo em anatomia humana

OBJECTIVE To evaluate the use of polyester resin in preserving anatomical specimens for the study of human anatomy. METHODS We used 150 anatomical specimens, comprised of unfixed (fresh), fixed in 10% formalin and vascular casts of organs injected with vinyl acetate and polyester resin. The solution used consisted of polyester resin with the diluent styrene monomer and catalyst (peroxol). After embedding in this solution, models in transparent resin were obtained, allowing full observation of structures and conservation of the specimens used. RESULTS upon evaluation of the specimens, we observed a high degree of transparency, which promoted a complete visualization of structures with perfect preservation of the anatomy. The average time for the completion of the embedding was 48 hours. Only 14 specimens (9.3%) were lost during the preparation. CONCLUSION Polyester resin can be used for preserving anatomical specimens for teaching human anatomy in a practical, aesthetic and durable way.

Análise da segmentação venosa hepática através de moldes de resina

OBJETIVO: Aferir a independencia da segmentacao da drenagem venosa hepatica, bem como a relacao entre seus segmentos. METODO: Foram utilizados trinta figados humanos, analisados cuidadosamente para exclusao de possiveis rompimentos extra e intra-parenquimatosos. Foi injetada uma resina sintetica (Resapol T-208) nas veias hepaticas direita, media e esquerda isoladamente, com diferentes cores, para identificacao dos segmentos, utilizando-se a tecnica de injecao-corrosao. Apos a obtencao dos moldes, foi realizada a pesagem e a planimetria destes, em conjunto e separadamente. RESULTADOS: Foi observado que todos os moldes hepaticos apresentaram independencia entre seus segmentos e que o segmento direito foi o maior (p=0,005). Ao correlacionar o peso do figado com a proporcao entre os segmentos, obteve-se um coeficiente de correlacao de 0,023. CONCLUSOES: Os segmentos das veias hepaticas sao independentes entre si, ocorrendo preponderância do segmento venoso direito sobre os demais e o aumento do peso do figado sem patologia corresponde a um aumento proporcional entre os seus segmentos.

Criss-cross heart: report of two cases, anatomic and surgical description and literature review

Criss-cross heart is an extremely rare anomaly, characterized by an abnormal rotation of the ventricular mass along its major axis. It may be associated with any malformation of the heart segments and connections. Due to the complex structural changes and rarity of the anomaly, the rotation of ventricular axis is often misdiagnosed. In this paper, two cases of criss-cross heart are reported, with emphasis on diagnostic and surgical techniques used to corrected the main defects. A literature review on the subject is also presented which, although sparse, emphasized on the morphologic, diagnostic and surgical aspects of the anomaly.

Accuracy of the pacemaker event recorder versus Holter-ECG to detect both symptomatic and asymptomatic ventricular arrhythmias

Although new pacemakers can register cardiac rhythm, few studies were performed evaluating their accuracy in diagnosing ventricular arrhythmias (VA). This study aimed to assess the correlation and agreement between the pacemakers monitor and the ambulatory Holter in detecting VA.