Studies on the anatomy of Piper leaves demonstrate the presence of a subepidermal tissue distinct from the adjacent epidermis, which cells show thin walls and hyaline contents. Some authors consider such cells a hypodermal tissue, while others refer to them as components of a multiple epidermis. In this study, the nature of this subepidermal tissue was investigated through the analysis of leaf ontogeny in three Piper species. The analysis showed that the referred tissue originates from the ground meristem and, thus, should be considered a hypodermis. The studied species suggests that the role of the hypodermis would be to protect the photosynthetic apparatus from excess light, regulating the intensity of light reaching the chlorophyll parenchyma.Keywords: hypodermis, multisseriate epidermis, Piperaceae. Origem do tecido subepidérmico em folhas de Piper L. ResumoOs estudos de anatomia foliar de espécies de Piper revelam a presença de um tecido subepidérmico distinto da epiderme e cujas células apresentam paredes finas e conteúdo hialino. Estas células são referenciadas por alguns autores como um tecido hipodérmico e por outros, como sendo constituintes de uma epiderme múltipla. Nesse estudo verificou-se a natureza deste tecido subepidérmico a partir da análise da ontogênese foliar de três espécies de Piper. A análise revelou que o referido tecido tem origem do meristema fundamental e, portanto, deve ser denominado de hipoderme. Para as espécies avaliadas, sugere-se que a hipoderme teria função de, proteger o aparato fotossintético do excesso de luminosidade, regulando a intensidade luminosa que atinge o parênquima clorofiliano.Palavras-chave: hipoderme, epiderme multisseriada, Piperaceae.

Sinus of Valsalva aneurysms are a rare pathology that can be clinically silent during years and/or become suddenly symptomatic. We described 3 cases with different clinical presentation, complications and surgical treatment. A 26-year-old male, competitive cyclist was admitted with a 1.5 month history of fatigue, palpitations, and nocturnal cough and sweating. At physical examination he was apyretic, blood pressure 157/49mmHg and radial pulse 96 bpm; jugular vein engorgement and continuous heart murmur, were noticed. Blood samples only revealed a mild raised BNP. EKG showed sinus tachycardia and right intraventricular conduction delay and the transthoracic echocardiography (TTE) revealed high velocity systolic-diastolic shunt (image) between a non-dilated right coronary sinus (RCS) and the right atrium (RA); moderate left ventricle dilation, severe right atrium and mild right ventricle enlargement with mild pulmonary hypertension and normal biventricular systolic function. He was referred to angioCT that showed a large communication between a non-dilated RCS and RA with signs of right ventricular overload. He was submitted to surgery, where ruptured aneurysm sac was found. Fistula closure, aneurysm sac suture and tricuspid annuloplasty were performed. A 45-year-old male asymptomatic, with no relevant medical background went to a Cardiology consultation after detection of a holossistolic murmur in the physical exam. EKG showed sinus rhythm arrhythmia with a nonspecific intraventricular conduction delay and the TTE revealed a communication between a dilated noncoronary sinus (NCS) and RA; the biventricular systolic function was normal. He was referred to angioCT which confirmed the diagnosis. He was submitted to surgery where an exeresis and closure of the fistula was performed. A 38-year-old male with no relevant medical background was admitted to emergence room for an intermittent anterior thoracic pain radiating to the neck (2 days of evolution). The EKG showed sinus tachycardia, incomplete right bundle branch block and the high-sensitivity troponin assays were negative. The TTE revealed severe sinus of Valsalva aneurysm, particularly of the NCS with mild aortic regurgitation. The patient performed transesophageal echocardiography and angioCT which excluded an acute aortic syndrome. He was oriented to surgery where a contained rupture of the RCS and a non-visualization of the ostium right coronary artery were detected, suggesting an intimal dissection. The patient was submitted to Bentall procedure and a bypass with internal mammary artery to right coronary artery. In spite of the unclear etiology, all the cases had a good clinical and echocardiographic evolution at follow-up. The difficulty in making a timely diagnosis is related to the variability of clinical presentation and the need of high clinical suspicion. Echocardiography and angioTC have demonstrated its value, in providing a prompt diagnosis and appropriate management guidance. Abstract P724 Figure. Ruptured aneurysm sac and fistula