**2. Clinical examination**

The main presenting complaints in cases of TP are often vague and non-specific; relating to milk drop, anorexia, lethargy, and weight loss [4, 10]. A review study demonstrated that in 60 animals diagnosed with fatal traumatic reticulitis (15 of which developed TP), the most common presenting sign was a sudden reduction in milk yield, which was observed in 68% of the cases.

Early signs of pericarditis, which can be detected through a clinical exam, include muffled heart sounds with associated splashing sounds, pericardial friction rubs, tachycardia, and pyrexia [10, 12]. Fluctuations in parameters such as rumen turnover, faecal output, heart rhythm, lung sounds and demeanour may also be found [12].

Pain is also an important component of TP which may present as bruxism, grunting, unwillingness to move, abducted elbows or a positive response to the cranial bar and withers test [10, 12]. Not all signs are present in every case, and they are also not exclusive to TP [12], other pathologies and physiological changes can be associated with such signs [11].

The signs mentioned above are also commonly seen in TRP cases irrespective of known TP development [7]. Clinical examinations alone have been shown to miss instances of TP. In a group of 28 animals which had TP, confirmed by necropsy, only 15 were diagnosed with TP using clinical examinations alone [13]. The lack of consistency in clinical signs between TP cattle is attributed to individuals presenting at different stages of disease with some showing evidence of HF. In addition, differences are observed as a result of the location of the foreign object, which specific anatomical structures the object has penetrated and the volume of fluid present in the pericardium [10]. Pregnancy and parturition have been also highlighted as possible contributing factors, due to increased pressure on the reticulum [13]. The variable degree of clinical signs and contributing factors associated with TP emphasises that only a tentative diagnosis can be made on clinical examination alone [4, 12, 14].

Some publications have emphasised that auscultation of the heart is the most significant aspect of a clinical exam in identifying pericarditis [3, 9]. Evidence of muffled heart sounds or other abnormal sounds such as splashing, tinkling, and rubbing are also commonly associated with pericarditis [11]. In a previous study, it was shown that muffled heart sounds had a sensitivity of 92% and specificity of 93% to pericarditis disease in 39 confirmed cases [6]. It should be noted that the presence of muffled heart sounds does not specify the type of pericarditis and the absence of such sounds does not necessarily rule out pericarditis [12]. Muffled heart sounds have also been demonstrated in other, non-cardiac diseases. One study observed muffled heart sounds in all 7 cases of pleurisy and all 5 cases of mediastinal abscesses, compared to only 39 of 55 TP cases [15]. This study also found that splashing and tinkling heart sounds were only found in the TP cattle, and not those with pleurisy or mediastinal abscesses. The presence or absence of tinkling sounds might help to rule in but not rule out TP.

Abnormal heart sounds do not always remain constant within TP cases, their presentation can change daily and the severity and time frame of disease progression of each animal should also be taken into account [16]. This highlights the need to reassess clinical signs in dubious cases. As well as auscultation, a full cardiac clinical exam should include assessment of mucous membrane colour, capillary refill time, a description of heart sound audibility and intensity with appreciation for cardiac rhythm and rate. In addition, pulse strength, rate, quality and the rhythm of both jugular and mammary veins, auscultation of lung fields and percussion of the cardiac region to assess level of cardiac dullness should be conducted [12, 17]. This comprehensive assessment allows for clarification of the clinical status of each cow and indicates whether there is potential disruption of the cardiac system. This can help indicate the most likely disease responsible, however, further diagnostic approaches are needed to fully determine the underlying aetiology and type of pericarditis, if present.

HF is the penultimate stage of all heart disease due to failure of the compensatory mechanisms [18, 19] (see **Figure 1**). Any heart disease seen in cattle can present with or without clinical signs of HF, as demonstrated in previous cases of pericarditis [19, 20]. Most clinical signs associated with chronic late stage TP relate to congestive right sided HF which can present with signs such as jugular distension, submandibular and brisket oedema [4].

It should be noted that a lack of any of the aforementioned signs of TP found on clinical examination does not mean that TP is not present. A study using clinical examination alone identified that 2 of 28 cattle under investigation had TRP with no signs of TP. However, on post mortem examination it was discovered that all 28 cases had profound signs of TP. This demonstrated that the development of TP in cases of TRP cannot be excluded via clinical assessment alone.

TP has been reported as the most common cause of pericardial disease and congestive heart failure (CHF) in cattle [15]. Despite this, other diseases should be considered when signs of congestive HF are apparent. Differentials include other causes of


#### **Table 1.**

*Commonly observed clinical signs associated with TP in order of their frequency in scientific studies.*

*Evaluation of Current and Future Diagnostic and Prognostic Techniques for Traumatic… DOI: http://dx.doi.org/10.5772/intechopen.106576*

pericarditis, bacterial endocarditis, primary dilated cardiomyopathy, congenital heart disease, cardiac lymphoma, mediastinal abscess and non-cardiac exudative pleurisy with much research evident on these other possible diseases too [10].

In conclusion, all differential diagnoses should be taken into careful consideration by the veterinarian when considering the presenting signs in suspected cases of TP. This is especially important in cases where presenting signs are vague or inconsistent. TP cannot always be ruled out by clinical examination alone and TP should always be considered when cattle present wit TRP. A full, cardiac clinical exam (**Table 1**) is paramount when reviewing the possibility of cardiac disease, to accurately provide diagnostic and prognostic information to the client.
