Sunday, February 1, 2015

The Necropsy on Cooper's Feline Moderator Band Cardiomyopathy Heart

We received the necropsy in September of Cooper's (who died August 2014) kidneys and heart we donated for research to MSU.

From the notes:

"...within the left ventricle of the heart there are excessive amounts of loose fibrous connective tissue lined by endothelium that span the interventricular septum to the left ventricular free wall and papillary muscles.  Subgrossly, sections of kidney have mild undulation of the capsular surface, with mild interstitial fibrosis of the subjacent cortical parenchyma.  Glomeruli have mild diffuse membranous glomerulonephropathy and there is multifocal thickening of basement membranes of Bowman's capsuleproximal convoluted tubules, and vesselsProximal tubular epithelial cells are swollen with finely vacuolated cytoplasm and occasionally faded nuclei. There are mild, multifocal lymphoplasmacytic interstitial infiltrates.  Gross examination of the heart finds excessive number of small, fine moderator bands towards the apex of the heart, extending from papillary muscles to the interventricular septum. There is an increased amount of white fibrous connective tissue along the endocardial surface of the left ventricle. Excessive moderator bands are considered under the heading of cardiomyopathies although it is considered a congenital defect that manifests later in life.  In this case, these moderator bands are visible grossly and histologically within the distal apex of the left ventricle.  The kidney lesions  suggest a mild nephritis of some chronicity, and these changes, in conjunction with reduced cardiac output and therapies to enhance diuresis in the animal, likely contributed to the reported azotemia prior to death."


Definitions: I tried to find definitions and explanations for what the notes mean.  These are not the best but this is what the above refers to.  Basically, damage was done to the kidneys, preventing them from processing the diuretic properly. The diuresis process could not keep congestion from the lungs.  In addition, of course, were the complications of the heart disease.  We believe he needed more potassium and supplements for kidney support while in the ER and every day.  There had been a slight improvement in his kidney values prior to his death but we only had had a month when we were giving extra supplements.  Given more time, I think we could have helped his kidneys improve their function and the diuresis process.  We see it working currently for Myrna, who, despite now on Torsemide, has normal kidney values (see  blog "Cat Living with Hypertrophic Cardiomyopathy", January 2015 posts):

Left ventricle-The left ventricle is one of four chambers of the heart. It is located in the bottom left portion of the heart below the left atrium, separated by the mitral valve. The thickest of all the chambers, the left ventricle pumps oxygenated blood to tissues all over the body. After flowing into the left atrium and through the mitral valve, blood enters the left ventricle before it is pumped out through the aortic valve into the aortic arch and onward to the rest of the body.

fibrous connective tissue- bands of tissue in the heart that normally serve a purpose

endothelium-thin layer of simple squamous cells that lines the interior surface of blood vessels and lymphatic vessels forming an interface between circulating blood or lymph in the lumen and the rest of the vessel wall.

interventricular septum-is the stout wall separating the lower chambers (the ventricles) of the heart from one another.

left ventricular free wall-The left ventricle free wall is composed of the area of the left ventricular wall not in contact with the interventricular septum and is not part of the apex.

papillary muscles-muscles located in the ventricles of the heart. They attach to the cusps of the atrioventricular valves (a.k.a. the mitral and tricuspid valves) via the chordae tendineae and contract to prevent inversion or prolapse of these valves on systole (or ventricular contraction).

undulation-marks that appear on the surface of the kidneys that appear to be up and down

capsular surface-thin membranous sheath that covers the outer surface of each kidney. The capsule is composed of tough fibres, chiefly collagen and elastin (fibrous proteins), that help to support the kidney mass and protect the vital tissue from injury.

interstitial fibrosis- characterized by the destruction of renal tubules and interstitial capillaries as well as by the accumulation of extracellular matrix proteins. The severity of tubulointerstitial fibrosis has long been considered as a crucial determinant of progressive renal injury in both human and experimental glomerulonephritis.

subjacent cortical parenchyma-The parenchyma are the functional parts of an organ in the body. This is in contrast to the stroma, which refers to the structural tissue of organs, namely, the connective tissues.

glomeruli- A tuft of capillaries situated within a Bowman's capsule at the end of a renal tubule in the vertebrate kidney that filters wasteproducts from the blood and thus initiates urine formation.

glomerulonephropathy-any noninflammatory disease of the renal glomeruli.

Bowman's capsule-a cup-like sac at the beginning of the tubular component of a nephron in the mammalian kidney that performs the first step in the filtration of blood to form urine.

proximal convoluted tubules and vessels-is the portion of the duct system of the nephron of the kidney which leads from Bowman's capsule to the loop of Henle.

Proximal tubular epithelial cells-Epithelium is one of the four basic types of animal tissue

vacuolated cytoplasm-A membrane bound organelle in the cytoplasm of most cells, especially plant cells, containing water and dissolved substances suchas salts, sugars, enzymes, and amino acids.

faded nuclei-nucleus or nuculeus, meaning kernel) is a membrane-enclosedorganelle found in eukaryotic cells. It contains most of the cell's genetic material, organized as multiple long linearDNA molecules in complex with a large variety of proteins, such as histones, to form chromosomes. The genes within these chromosomes are the cell's nuclear genome. The function of the nucleus is to maintain the integrity of these genes and to control the activities of the cell by regulating gene expression—the nucleus is, therefore, the control center of the cell. 

lymphoplasmacytic interstitial infiltrates-of, relating to, or consisting of lymphocytes and plasma cells.  Interstitial Infiltrates occur within the connective tissue surrounding the air spaces.


papillary muscles- muscles located in the ventricles of the heart. They attach to the cusps of the atrioventricular valves (a.k.a. the mitral and tricuspid valves) via the chordae tendineae and contract to prevent inversion or prolapse of these valves on systole (or ventricular contraction).

interventricular septum-stout wall separating the lower chambers (the ventricles) of the heart from one another.

endocardial surface of the left ventricle-endocardium is the innermost layer of tissue that lines the chambers of the heart. Its cells are embryologically and biologicallysimilar to the endothelial cells that line blood vessels. The endocardium also provides protection to the valves and heart chamber

No comments:

Post a Comment