Sex variation in occurrence of myocardium in human mitral valve cusps / Variación del sexo en la aparición del miocardio en cúspides de la válvula mitral humana

Mitral valve cusps consist mainly of connective tissue and myocardium. Connective tissue fibres within the cusps have been demonstrated to exhibit sex variations in organisation. Mitral prolapse, a disease attributed to defects within the cusps occurs more commonly in females. Sex variations in valvular myocardium however remain to be studied. Possible variations in its organisation may enhance understanding of sex differences in prevalence of mitral prolapse. The aim of this study was to determine anatomical variations of mitral valvular myocardium by sex; by mean a comparative cross-sectional study. A total of 48 (27 male and 21 female) adult heart specimens obtained during autopsy at Nairobi City and Chiromo mortuaries after ethical approval were used. Valvular cusps were then harvested. Four ¡ millimetre sections were made at the area of maximum width for both anterior and posterior cusps. These were processed for paraffin-embedding and sectioning and stained with Masson's trichrome and Weigert's resorcin fuchsin with Van Gieson counterstain to demonstrate cardiac muscle, collagen and elastic fibres. Both anterior and posterior cusps demonstrated three histological laminae, that is, atrialis, fibrosa and ventricularis. Only lamina atrialis contained cardiac muscle. This lamina in males was characterised by a transversely oriented subendothelial myocardial strip while that in females contained compact longitudinal elastic fibres but no muscle. The presence of cardiac muscle in the lamina atrialis may be relatively protective against mitral valve prolapse in males compared to females.

Las cúspides de la valva mitral están constituidas principalmente por tejido conectivo y miocardio. Se ha demostrado que las fibras del tejido conectivo de las cúspides presentan diferencias en la organización según sexo. El prolapso mitral, una enfermedad atribuida a defectos en las cúspides es más frecuente en las mujeres. Las variaciones de sexo en el miocardio valvular sin embargo aún no se han estudiado. Las posibles variaciones en su organización puede mejorar la comprensión de las diferencias de sexo en la prevalencia de prolapso mitral. El objetivo de este estudio fue determinar las variaciones anatómicas del miocardio valvar mitral por sexo, por medio un estudio comparativo de corte transversal. Un total de 48 los especímenes de corazón adulto (se utilizaron 27 hombres y 21 mujeres), obtenidos durante autopsias en la ciudad de Nairobi y desde el depósito de cadáveres Chiromo, después de la aprobación ética. Las cúspides valvares fueron extraídas. Fueron realizadas secciones de cuatro milímetros en el parte más ancha de las cúspides anteriores y posteriores. Estas fueron procesadas por inclusión en parafina, corte y tinción con tricrómico de Masson y fucsina-resorcina de Weigert con contraste Van de Gieson, para demostrar la presencia de músculo cardíaco, fibras colágenas y elásticas. T.

Perforated Peptic Ulcer Disease at Kenyatta National Hospital; Nairobi

Background: Published reports on perforated peptic ulcers indicate increasing rates for the elderly; those chronically ill and females. Our local observations are at variance. This study analysed patients treated for peptic ulcer perforations at the Kenyatta National Hospital between January 2005 and December 2006. Methods: Clinical charts for patients admitted and treated for perforated peptic ulcer disease were reviewed. Data sought included patient demographic data; clinical presentation; and time from onset of symptoms to treatment; operative findings and treatment mplications. The determinants of post-operative complications were evaluated using univariate analysis. Results: Forty four patients with perforated ulcers were admitted and treated over a two year study period. Twenty eight were analyzed (retrieval rate 63.6). Males (86.2) and those 35 years of age and younger (57.1) predominated. Alcohol; smoking and prior use of non steroidal anti inflammatory drugs were respectively documented in 39.3; 39.3and 10.7of patients. The complication rate was 25. Four patients died. The factors significantly related to complications was treatment delay (p=0.007) and acute perforation (0.027) Conclusion: Perforated peptic ulcer disease is a disease of young males. Efforts to reduce delay in presentation in this population may reduce the complications

Prevalence and Distribution of the Third Coronary Artery in Kenyans / Prevalencia y Distribución de la Tercera Arteria Coronaria en Kenianos

A third coronary artery (TCA) has been defined as a direct branch from the right aortic sinus (RAS) that contributes to the vascularization of the infundibulum of the right ventricle (RV). The distribution of this artery may be important in surgical procedures and in understanding the extent and progression of acute myocardial infarction. Its reported prevalence however shows ethnic disparity. The aim of the study was describe the prevalence and distribution of the third coronary artery in a Kenyan population. 148 cadaveric and postmortem human adult hearts obtained from the Department of Human Anatomy, University of Nairobi, and the Chiromo and Nairobi city mortuaries were used after an ethical approval. The hearts were studied by gross dissection for the prevalence and topographical anatomy of the TCA. Data was coded and analyzed using SPSS. The TCA is present in 35.1% of the heart specimens. It was variably distributed to the conducting system (23%), anterior wall of the RV (100%), interventricular septum (IVS) (51.9%) and the apex of the heart (5.8%). The TCA, with substantial contribution to cardiac vascularization, may be present in about a third of the Kenyans. It may constitute a significant collateral circulation to apical and septal perfusión. Interpretation of signs and symptoms of coronary occlusion should therefore consider possible contribution of this vascular channel.

La tercera arteria coronaria (TCA) ha sido definida como una rama directa del seno aórtico derecho (RAS) y contribuye a la vascularización del cono arterioso del ventrículo derecho (RV). La distribución de esta arteria puede ser importante en los procedimientos quirúrgicos y para comprender la magnitud y progresión del infarto agudo del miocardio. El reporte de su prevalencia, sin embargo, muestra disparidad étnica. Se describen la prevalencia y distribución de la tercera arteria coronaria en la población keniana, en un estudio transversal. Se utilizaron 148 corazones de cadáveres adultos, obtenidos del Departamento de Anatomía de la Universidad de Nairobi y de las morgues, de las ciudades de Chiromo y Nairobi, luego de su aprobación ética. Se estudiaron en los corazones por medio de la disección macroscópica, la anatomía topográfica de la TCA y su prevalencia. Los datos fueron codificados y analizados utilizando el software SPSS. La TCA estuvo presente en el 35,1% de los corazones. Su distribución variable fue del 23% en el sistema de conducción cardíaco, un 100% en la pared anterior del ventrículo derecho, 51,9% en el septo interventricular (IVS) y en el ápex del corazón un 5,8%. La tercera arteria coronaria contribuye sustancialmente a la vascularización cardiaca y puede estar presente en cerca de un tercio de los kenianos. Esto puede constituir una significativa circulación colateral para la perfusiones apical y septal. En la interpretación de signos y síntomas de oclusión coronaria se puede considerar la posible contribución de este vaso.