Retrospective evaluation of clinical signs, clinical course, and prognosis between dogs with left atrial rupture secondary to myxomatous mitral valve disease and those with neoplastic cardiac tamponade (2015-2019): 70 cases.

OBJECTIVE: To describe the clinical signs, clinical course, and prognosis of suspected left atrial rupture (LAR) secondary to myxomatous mitral valve disease (MMVD) in dogs and to compare them with dogs with suspected neoplastic cardiac tamponade (NCT). DESIGN: Retrospective study from November 2015 to October 2019 SETTING: An out-of-hours Emergency Animal Hospital. ANIMALS: Twenty-three dogs with LAR secondary to MMVD (LAR group) and 47 dogs with NCT (NCT group). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The following were the characteristics of the study population (LAR group vs NCT groups) with P < 0.05 as the significance threshold: male sex, 83% vs 66%; median age, 11.9 vs 12.5 years; and median weight, 3.8 vs 6.4 kg (P < 0.001). Chihuahuas and Miniature Dachshunds were overrepresented in the LAR and NCT groups, respectively. Statistically different clinical findings between the 2 groups were as follows (LAR vs NCT): pulmonary edema, 43% vs 0%; pericardial thrombus, 70% vs 6% (P < 0.001); ineffectiveness of pericardiocentesis (whether aspiration of pericardial fluid was successful or not), 58% vs 2% (P < 0.001); mortality rate within 48 hours of visiting hospital, 35% vs 9% (P < 0.01). No significant difference was observed in survival time after discharge between the 2 groups. CONCLUSIONS: The proportion of dogs with a diagnosis of LAR secondary to MMVD in dogs with cardiac tamponade was higher than the previously reported rate. Furthermore, the frequency of pulmonary edema, ineffectiveness of pericardiocentesis, and short-term mortality rate was higher in the LAR group than in the NCT group.

Rare delayed cardiac tamponade in a pig after cardiac surgery.

OBJECTIVE: Delayed cardiac tamponade, a life-threatening complication of pericardial effusion in humans, has rarely been described in large animal models. We report here a pig with cardiac tamponade that developed 29 days after cardiac surgery. STUDY DESIGN: Case report. ANIMALS: One 45-kg domestic pig. METHODS: Open-chest surgery was performed on a pig to induce chronic heart failure. At 15 days after surgery, the pig's breathing appeared laboured; induced heart failure was considered the cause. Routine heart failure medications were administered. RESULTS: On day 28, the pig's status deteriorated. On day 29, echocardiography performed just before the pig's death showed a large pericardial effusion, mainly in the lateral and anterior walls of the right heart, with several fibre exudation bands. The right heart was severely compressed with an extremely small right ventricle. An emergency sternotomy was unsuccessful. Pathologic examination showed a severely thickened, fibrous pericardium. The pericardial sac was distended (up to 4.5 cm) and was full of dark brown, soft, friable material. Epicardial haemorrhage with a fresh, organised thrombus was noted in the pericardium. CONCLUSION: Delayed tamponade occurring at least 15 days after open-chest surgery is easy to misdiagnose or overlook in large animal models where attention is often focused on primary pathological model changes. To decrease mortality in animal models, researchers should be aware of potential complications and use the same level of follow-up monitoring of large animals as in clinical care.

Septic pericarditis caused by a migrating grass awn in a cat.

Septic pericarditis and cardiac tamponade associated with migrating grass awn foreign bodies is reported rarely in companion animals. We report such a case in a previously healthy, 9-year-old, neutered female, indoor-outdoor, domestic long-hair cat who presented for acute tachypnea. Large volume pericardial effusion and pericardial tamponade was identified by thoracic-focused assessment with sonography. Following removal of 108 mL of purulent pericardial effusion by pericardiocentesis, the cat improved. Cytologic examination of pericardial fluid demonstrated septic, suppurative inflammation, Pasteurella sp. was cultured from pericardial effusion, and antibiotics were administered. Subsequent echocardiographic examination revealed large volume pericardial effusion, pericardial thickening, and a linear foreign body within the pericardial space. Whole-body computed tomography confirmed pericardial thickening, pericardial, and pleural effusion. A 16-mm long grass awn was identified within the pericardial space during thoracic exploratory surgery performed through a median sternotomy. Successful foreign body removal and subtotal pericardiectomy was accomplished. Histopathology of pericardial tissue disclosed chronic pericarditis with lymphoplasmacytic-to-pyogranulomatous inflammation, and transmural presence of grass awn foreign body. The cat responded to supportive therapy and was discharged 4 days postoperatively. When examined 3 weeks later, the cat appeared healthy with normal appetite. The cat remained healthy as of this writing, 487 days following surgery. To the author's knowledge, this is the first report in the cat of septic pericarditis and cardiac tamponade resulting from a migrating grass awn foreign body.

Giant pericardial-occupying compressive primary cardiac hemangiosarcoma in a cat.

Hemangioarcoma in the cat is an infrequently diagnosed tumor, and cardiac involvement is rare. We report a previously healthy, 8-year-old, domestic shorthair cat with acute collapse associated with pericardial effusion and cardiac tamponade. Following pericardiocentesis and removal of 15 mL of fluid, the cat improved rapidly. A massive, space-occupying, intrapericardial tumor adhered to and compressing the right atrium and ventricle was detected by echocardiography. Approximately 5 weeks following initial presentation, bicavitary effusion and tachypnea developed, and the cat was euthanized. Necropsy revealed a giant intrapericardial mass adhered to and impinging upon the right heart. Histologic and immunohistochemical examination confirmed hemangiosarcoma with no gross or histologic evidence of metastasis. To the authors' knowledge, this is the first account of a pericardial-occupying, primary feline cardiac hemangiosarcoma resulting in compression of the right heart and cardiac tamponade, Further, this report describes novel clinicopathological relationships between radiographic and echocardiographic findings and gross and microscopic pathology.

Effects of Right Atrioventricular Expanded Polytetrafluoroethylene Path Graft Reconstruction on Arrhythmogenicity and Ventricular Function in Dogs.

Right atrioventricular pericardial autografts, including the coronary groove, may cause myocardial ischemia. Our aim was to explore the effects of this procedure using an expanded polytetrafluoroethylene (ePTFE) patch on arrhythmogenicity and right ventricular function. Four healthy beagles and one client-owned golden retriever with recurrent cardiac tamponade as a result of hemangiosarcoma were included. The four healthy dogs underwent right atrioventricular ePTFE patch graft reconstruction after complete resection of the right auricle. Right ventricular function and arrhythmia were evaluated using tricuspid annular plane systolic excursion and tissue Doppler imaging on echocardiography and Holter electrocardiography, respectively, before and after surgery. The golden retriever underwent right atrioventricular ePTFE patch graft reconstruction followed by resection of the cardiac mass. None of the echocardiographic values, not involving systolic function, changed after surgery in the four healthy dogs. Transient arrhythmias tended to increase 1 day after surgery. The dog with recurrent cardiac tamponade exhibited more severe arrhythmia and required transient antiarrhythmic treatment for 3 days and survived the cardiac tamponade for 434 days after surgery. We showed that an ePTFE patch can serve as a suitable alternative material for right atrioventricular patch graft reconstruction, although transient arrhythmias may occur following surgery.

Canine leishmaniasis associated with pericardial effusion in a 4-year-old dog.

A 4-year-old crossbreed dog presented with a two-day history of lethargy and abdominal effusion. Physical examination and echocardiography revealed pericardial effusion with cardiac tamponade. Pericardiocentesis was performed. Intracytoplasmic Leishmania amastigotes were found on cytological examination of the pericardial fluid. The animal was treated with N-methylglucamine antimoniate and allopurinol. After an initial favorable response, cardiac tamponade reoccurred one month later. The dog died during a pericardiectomy four months after the initial diagnosis. Histology confirmed the presence of chronic pericarditis. The presence of Leishmania amastigotes on cytological examination of pericardial effusion suggests a possible association between canine leishmaniasis and chronic pericarditis. This finding also supports the importance of cytological examination of pericardial fluid in areas endemic for canine leishmaniasis.

Evaluation of Pericardial Effusion in Dogs and Successful Treatment Using a Hemodialysis Fistula Needle: A Retrospective Study.

The aim of this retrospective study was to assess epidemiology and echocardiographic findings of pericardial effusion in canine patients and to determine the clinical usefulness and safety of a new pericardiocentesis technique, using a "fistula needle" for hemodialysis. A database of 5304 dogs of different breeds, age, gender, type, and severity of the cardiac disease, referred for a specialist cardiology and echocardiographic examination from 2009-2016, was reviewed. All the dogs were subjected to echocardiography; when possible and required, an echo-guided pericardiocentesis was performed by mean of a 17G "fistula needle" commonly used for hemodialysis. Complete echocardiography was repeated at the end of each pericardiocentesis. Pericardial effusion was identified by echocardiography in 91 dogs (1.71%), 20 were female (21.98%) and 71 were male (78.02%). PE caused cardiac tamponade in 38/91 cases (41.76%). A clear evidence of a neoplasm was found in 33 cases (36.26%). In 32 cases (35.16%) severe degenerative mitral and tricuspid valve disease was detected as the cause of the pericardial effusion. Echo-guided pericardiocentesis was performed in 28 cases (30.77%) with cardiac tamponade. No adverse effects were found in any of the patients during the 48 hours of follow up after pericardiocentesis. This study showed the high incidence of pericardial effusion due to severe bilateral degenerative valve disease in adult to elderly dogs of different breeds. Moreover, the use of a "fistula needle" for pericardiocentesis in dogs showed no adverse effects.

Plasma N-terminal pro-brain natriuretic peptide concentrations before and after pericardiocentesis in dogs with cardiac tamponade secondary to spontaneous pericardial effusion.

OBJECTIVE: To determine if concentrations of plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) are increased in dogs with cardiac tamponade and if there is a significant increase in plasma NT-proBNP after pericardiocentesis. ANIMALS: Ten client-owned dogs with spontaneous cardiac tamponade. METHODS: Prospective clinical study. Cardiac tamponade was suspected from physical examination and confirmed with echocardiography. Blood was collected and plasma NT-proBNP concentrations were measured before and 30-60 min following pericardiocentesis and resolution of cardiac tamponade. Within-subject changes in plasma NT-proBNP were compared by the Wilcoxon signed-rank test. RESULTS: The plasma NT-proBNP concentrations measured within the reference interval in seven of 10 dogs before pericardiocentesis and in six of 10 dogs following pericardiocentesis. Following pericardiocentesis, there was a statistically significant increase in median NT-proBNP concentration (733 pmol/L, range 250-3,297) compared with the values measured before (643 pmol/L, range 250-3,210, P = 0.004). The NT-proBNP concentration increased in 90% of the dogs following pericardiocentesis. CONCLUSIONS: An upper reference limit of 900 pmol/L for plasma NT-proBNP is insensitive for the diagnosis of pericardial effusion and cardiac tamponade in dogs. Plasma NT-proBNP concentration commonly increases following pericardiocentesis, perhaps related to improved ventricular filling and stretch.

Focal intramural pericardial effusion and cardiac tamponade associated with necrotic adipose tissue in a dog.

CASE DESCRIPTION A 1-year-old castrated male German Shepherd Dog was examined because of an acute onset of lethargy, tachypnea, and inappetence. CLINICAL FINDINGS On initial physical examination, the dog was tachypneic with muffled heart sounds on thoracic auscultation and a palpable abdominal fluid wave. Transthoracic echocardiography revealed focal intramural pericardial effusion and cardiac tamponade. TREATMENT AND OUTCOME The patient underwent emergency therapeutic pericardiocentesis, followed by right lateral intercostal thoracotomy and subtotal pericardiectomy. A 3 × 5-cm mass located between the parietal and visceral layers of the pericardium was resected. The histologic diagnosis was necrotic adipose tissue with granulomatous inflammation and fibroplasia. The patient also underwent exploratory laparotomy and umbilical herniorrhaphy during the same anesthetic episode and recovered from surgery without apparent complications. There were no further clinical signs of cardiac disease. CLINICAL RELEVANCE The patient described in the present report underwent successful subtotal pericardiectomy for treatment of a benign focal lesion causing recurrent pericardial effusion and cardiac tamponade. Prompt diagnosis and intervention may have contributed to the positive outcome in this case.

Echocardiographic findings and clinical signs in dairy cows with primary cardiac lymphoma: 7 cases (2007-2010).

OBJECTIVE: To describe echocardiographic and clinical findings in cattle with cardiac manifestation of lymphoma. DESIGN: Retrospective case series. ANIMALS: 7 adult Holstein dairy cows with cardiac lymphoma. PROCEDURES: Medical and necropsy records of all cows that underwent transthoracic echocardiography from January 2007 through April 2010 because of clinical signs of cardiac diseases or bovine lymphoma were reviewed. The diagnosis of cardiac manifestation of lymphoma was confirmed by necropsy examination or cytologic evaluation of pericardial fluid obtained by pericardiocentesis. RESULTS: Most commonly, cows had clinical signs of right-sided congestive heart failure secondary to cardiac tamponade with moderate to severe anechoic pericardial effusion (5/7 cows). In 2 cows, tachycardia was the only clinical sign in relation to cardiac disease and a heterogenic mass was observed protruding into the right atrium. CONCLUSIONS AND CLINICAL RELEVANCE: The use of transthoracic echocardiography aided in the diagnosis of primary cardiac lymphoma in cows. Transthoracic echocardiography may help to quantify the severity of pericardial effusion and to orient needle placement for pericardiocentesis to determine a final diagnosis. A mass within the right atrium was also suggestive of cardiac lymphoma and should be differentiated from mural bacterial endocarditis.

Repeated pericardiocentesis as palliative treatment for tamponade associated with cardiac lymphoma in a Holstein cow.

Maintaining a good quality of life for cows with cardiac manifestation of lymphoma may be valuable, especially in high-producing cows. This report describes the medical management of cardiac lymphoma in a cow by means of repeated pericardiocentesis. The cow survived for 34 days and was productive.

Hepatic myelolipoma incarcerated in a peritoneopericardial diaphragmatic hernia in a cat.

Hepatic myelolipoma incarcerated in a peritoneopericardial diaphragmatic hernia was diagnosed in an 11-year-old, desexed female Persian cat. The cat was initially referred for investigation of tachypnoea and dyspnoea. Peritoneopericardial diaphragmatic hernia is a common incidental finding in cats and is usually asymptomatic. Myelolipoma is an extremely rare benign tumour, composed of extramedullary haematopoietic cells and adipose tissue. Myelolipomas are hypothesised to result from metaplastic alteration, rather than a neoplastic process, although this theory cannot be substantiated. The present case is only the fourth report of such an unusual occurrence in cats and displays significant differences to previous reports. Hepatic entrapment and burgeoning of the mass within the pericardial sac resulted in cardiac tamponade and overt signs of right-sided cardiac failure. Surgical intervention was successful and despite concerns regarding the cat's clinical presentation and the gross appearance of the lesion(s), a good long-term outcome is anticipated.

Chronic cardiac tamponade in a cat caused by an intrapericardial biliary cyst.

A 1-year-old domestic longhair cat presented to our hospital with a 4-month history of progressive exercise intolerance and coughing. Two-dimensional echocardiography confirmed the presence of an intrapericardial cyst and cardiac tamponade. Tamponade was relieved via percutaneous aspiration of the cyst. The cyst was surgically excised 4 days later, and histopathology was consistent with a biliary cyst. The cat's clinical signs completely resolved following surgery.

Pericardial effusion and cardiac tamponade caused by intrapericardial granulation tissue in a dog.

OBJECTIVE: To describe and report successful surgical management of pericardial effusion and cardiac tamponade in a dog caused by intrapericardial granulation tissue. CASE SUMMARY: An 8-month-old, intact male, Greater Swiss Mountain Dog was referred for cardiac evaluation following 2 weeks of progressive lethargy, abdominal distention, and difficulty breathing. On the day of presentation, the dog had an episode of acute collapse. A 14-cm multilocular pericardial cystic lesion causing collapse of the right atrial free wall and resulting in pericardial tamponade was observed on echocardiogram. After the dog subsequently experienced two acute episodes of pericardial effusion, a subtotal pericardectomy was performed and clinical signs resolved. The histopathologic diagnosis of the mass was inflammation and granulation tissue, likely caused by a resolving hematoma or abscess. NEW OR UNIQUE INFORMATION PROVIDED: This is the first report of intrapericardial granulation tissue as the cause of pericardial effusion and cardiac tamponade.

Septic pericardial effusion associated with pulmonary and pericardial botryomycosis in a dog.

The authors report a case of septic pericardial effusion resulting in cardiac tamponade associated with intrathoracic botryomycosis in a dog. Septic pericarditis and a pulmonary mass were diagnosed, and subtotal pericardiectomy and lobectomy of the affected pulmonary areas were carried out. Histopathology of the excised tissue showed changes supportive of botryomycosis--namely a pyogranulomatous inflammation with neutrophils centred around amorphous homogeneous eosinophilic material and club-like bodies containing Gram-positive bacterial cocci present in the centre. The patient recovered well following surgery and antibiotic therapy. To the authors' knowledge, this is the first report of pulmonary botryomycosis in the dog and the first report of this condition presented with pericardial involvement and cardiac tamponade in any species.

Canine pericardial effusion: pathophysiology and cause.

Pericardial effusion is the abnormal accumulation of fluid in the pericardial space. As the fluid volume and intrapericardial pressure increase, cardiac tamponade can develop. The most common causes of pericardial effusion include cardiac hemangiosarcoma, idiopathic pericardial effusion, and chemodectoma. Understanding the underlying cause is important in providing treatment recommendations and an accurate prognosis.

Marked pleural effusion causing right atrial collapse simulating cardiac tamponade in a dog.

A 16-month-old, female German shepherd dog was presented with severe bicavitary effusions. A diaphragmatic hernia was diagnosed by thoracic radiography. An echocardiogram performed prior to surgical repair of the hernia revealed signs of cardiac tamponade, with right atrial collapse, in the absence of pericardial effusion. Right atrial collapse was presumed to be secondary to severe pleural effusion. At surgery, no pericardial disease was identified. Surgical correction of the diaphragmatic hernia resulted in resolution of the pleural and peritoneal effusions. Follow-up echocardiography demonstrated resolution of the signs of cardiac tamponade.

Idiopathic pericarditis and cardiac tamponade in two cows.

Idiopathic pericarditis is an uncommon diagnosis in cattle with cardiac tamponade. Two cows were examined for clinical signs of right-sided congestive heart failure, including tachycardia, venous distention, and peripheral edema. Muffled heart sounds were detected in one of the cows. Echocardiography in both cows revealed voluminous anechoic pericardial effusion and compression of the right atrium and right ventricle. Cytologic analysis of the pericardial fluid revealed hemorrhagic inflammation but no evidence of a septic or neoplastic condition such as traumatic reticulopericarditis or lymphoma, respectively. Pericardial drainage and lavage accompanied by treatment with anti-inflammatory drugs were curative in both cows. It is important to differentiate cows with idiopathic pericarditis from cows with more common septic pericarditis because the prognosis for the former disease appears to be good with appropriate treatment.

Pericardial effusion and cardiac tamponade in a cat with extranodal lymphoma.

A five-year-old domestic longhaired cat was evaluated for a seven-day history of worsening respiratory distress. Serum analysis for feline leukaemia virus antigen was positive. Pleural effusion was detected on thoracic radiographs and echocardiography revealed a pericardial effusion and cardiac tamponade. Cytological evaluation of the pleural and pericardial effusions showed lymphoblastic cells indicative of disseminated lymphoma. Following thoracocentesis and pericardiocentesis, the cat was treated for lymphoma using the University of Wisconsin-Madison chemotherapy protocol. The cat was sent home after three days and, at the time of writing (six months after initial presentation), was still symptom free. To the authors' knowledge, this is the first report confirming pericardial effusion and cardiac tamponade in the cat as a direct result of an extranodal lymphoma with cytological evidence of neoplastic cells in the pericardial fluid.

[Cardiac tamponade due to pericardial mesothelioma in an 11-year-old dog: diagnosis, medical and interventional treatments]. / Herztamponade durch ein Perikardmesotheliom bei einem 11-jährigen Hund: Diagnose, medikamentelle und interventionelle Behandlungen.

In a dog presenting with the clinical signs of exercise intolerance and ascites, cardiac tamponade due to suspected idiopathic pericarditis was diagnosed based on thoracic radiographs, electrocardiogram (EKG) and cardiac ultrasound. Pericardial effusion recurred soon after pericardiocenteses, prescription of colchizine and again after balloon pericardiotomy. After partial pericardectomy by thoracoscopy and after obtaining a histological diagnosis of mesothelioma adjuvant intracavitary chemotherapy using cisplatin was performed. Already one week later the dog developed marked dyspnea due to severe pleural effusion. The dog was maintained at acceptable life quality judged based on playfulness and appetite using repeated pleuro-centeses for an additional two months, when the dog was euthanized due to uncontrollable pleural effusion. Despite extensive treatments life span from initial presentation to euthanasia was only 5 months. Necropsy revealed extensive mesothelioma metastases covering the whole pleura, epicardium and remaining pericardium. Diagnostic and therapeutic aspects of (recurrent) pericardial effusion are discussed based on this case.