Necropsy results for sudden death of standard poodle - spoiler: a whole lot of nothing.

Background: very healthy, energetic standard poodle died suddenly (no apparent pre existing issues, no coughing/sneezing/etc)

Age: just turned 9

Behavior leading up to death: eating well, energetic, very normal. Slightly unusual behavior: Overly clingy for a few months leading up to death (but this was also kind of her temperament; very loving dog) and randomly a little skittish (ex: a few days before death I noticed that she got spooked/briefly shaky when a cabinet shut, thunder, or when my child randomly clapped)

Death: laying down inside on dog bed and let out a horrific howl, then had a very difficult time breeding for about a minute, and then was gone.

RESULTS:

Gross Pathology The carcass was mildly autolyzed. External: The subcutaneous and visceral adipose stores were slightly increased with adequate muscle mass. Mild amounts of calculi were upon the premolars and molars of all arcades. Small amounts of red-tinged, watery fluid exuded from the nares.

Internal: Cranium: The nasal turbinates were diffusely dark red and hemorrhagic. Thorax: The caudal third of the trachea was mildly widened and flattened with a stretched tracheal membrane (tracheal dysplasia). The lungs were diffusely dark red, wet and heavy, oozing red-tinged fluid upon sectioning. All lung lobes floated when placed into 10% neutral-buffered formalin. The right ventricular free wall, interventricular septum, and left ventricular free wall of the heart were 0.7 cm, 1.7 cm, and 1.5 cm, respectively. The mitral valve contained few, pinpoint, tan nodules (endocardiosis).

Abdomen: The splenic tail contained a round, soft, smooth, 2.0 x 3.0 x 3.0 cm nodule. Upon sectioning, the nodule was solid, tan and friable. The stomach was moderate gas distended and contained moderate amounts of soft, brown to tan, granular to semisolid ingesta. The intestines were diffusely gas distended. The duodenum to mid-jejunum contained scant, tan pasty digesta. The remainder of the jejunum contained small amounts of orange to brown, watery digesta. The ileum contained small amounts of green, thick digesta. The descending colon contained a moderate amount of soft, brown, unformed feces.

Diagnosis Gross diagnoses: Nasal turbinates: Rhinitis, hemorrhagic, moderate, diffuse, acute Spleen: Splenic nodule, focal Trachea: Tracheal dysplasia, mild, focally extensive (incidental) Heart: Valvular endocardiosis, mild, mitral, chronic

Comments Post-mortem evaluation did not reveal an overt cause of mortality. The most significant findings were diffuse pulmonary congestion and hemorrhagic sinuses which may indicate a degree of respiratory disease and compromise. The splenic nodule appearance is suggestive of benign nodular hyperplasia; however, other processes such as neoplasia cannot be ruled out. The valvular endocardiosis is mild and likely age-related without significant contribution to overall mortality. No overt evidence of neoplasia, trauma or endoparasites (including heartworm) are identified macroscopically.

Any hypothesis? Not asking for a diagnosis, not asking for anything other than treating this as a school-style hypothetical as to what may have happened.