Percutaneous balloon pericardiotomy as a treatment for recurrent pericardial effusion in 6 dogs

Percutaneous balloon pericardiotomy (PBP) has been performed in people and in a small number of dogs as a treatment for recurrent pericardial effusion with tamponade (PET). We performed this technique on 6 dogs with recurrent PET (5 with heart base tumors and 1 with no identifiable mass). Under general anesthesia and fluoroscopic guidance, a balloon-dilating catheter (diameters 14-20 mm) was introduced percutaneously at the 5th intercostal space through a sheath-introducing catheter, positioned across the parietal pericardium, and inflated 3 times. No dog experienced serious complications. The procedure was considered successful in 4 of 6 dogs. One dog is still alive without recurrence of PET 1 year after the procedure. Three dogs died of unrelated disease without recurrence of PET 5. 19, and 32 months after the procedure. The procedure was not beneficial in 1 dog that was euthanized 9 weeks later because of recurrence of pleural and abdominal effusion thought to be secondary to PET. One dog may have temporarily benefited but developed symptomatic PET 6 months after PBP. PBP appears to be a safe, economical, and potentially effective palliative treatment for recurrent PET and is a reasonable, less invasive alternative to surgery for dogs with recurrent PET, especially effusions caused by heart base tumors and possibly idiopathic pericardial effusion. Premature closure of the stoma is a potential cause for long-term failure and was thought to have been responsible for the recurrence of clinical signs in 2 dogs.     

Pericardial effusion associated with metastatic disease from an unknown primary tumor in a dog

A 6.5-year-old, spayed female Siberian husky presented with signs of cardiac tamponade and weakness. Pleural, pericardial, and abdominal effusion were identified with radiographs and ultrasound. Pericardiocentesis relieved signs of tamponade, and the dog was clinically improved. Pericardial effusion recurred, and pericardiectomy was performed. Histopathological examination of excised tissues failed to reveal evidence of infectious or neoplastic disease. After pericardiectomy, clinically apparent thoracic effusion persisted. The dog was euthanized, and postmortem histopathological examination revealed emboli of metastatic carcinoma cells in the epicardium. The location of intrathoracic disease in this dog made antemortem diagnosis difficult, if not impossible.     

Evaluation of the presence of selected viral and bacterial nucleic acids in pericardial samples from dogs with or without idiopathic pericardial effusion

Many viruses have been identified in pericardial fluid and in tissue samples from humans with pericarditis by means of molecular diagnostics. In canine idiopathic pericardial effusion there is as yet no conclusive evidence to support the involvement of an infectious agent. This study was designed to investigate a possible relationship between idiopathic pericardial effusion in dogs and viruses most commonly encountered in humans affected with viral pericarditis. Coxsackievirus B3 RNA, influenza virus type A RNA, human adenovirus type 2 DNA, human cytomegalovirus DNA, and parvovirus B19 DNA were investigated using PCR on pericardial effusion samples and pericardial tissue specimens collected from 14 dogs with idiopathic pericardial effusion. PCR was also used to test for two bacteria, Borrelia burgdorferi and Chlamydia pneumoniae. The same microorganisms were also looked for in pericardial effusions or pericardial washes from 10 dogs with neoplastic pericardial effusion, and in samples collected from 10 dogs which died of a non-cardiac disease. One pericardial effusion sample from a dog with the idiopathic form of the disease tested positive for influenza virus type A and sequencing of the amplicon confirmed the PCR result. In another dog from the same group a cytomegalovirus was detected by PCR in the effusion, but sequencing showed this to be a false-positive result. The genomes of the microorganisms investigated were not detected in neoplastic effusions or pericardial washes. The results indicate that viral and bacterial DNA/RNA of relevance for human pericarditis is rare in pericardial samples from dogs with idiopathic pericardial effusion. The finding of influenza type A viral RNA in pericardial fluid from one dog with the idiopathic form of the disease warrants further investigation.     

Idiopathic hemorrhagic pericardial effusion in eight dogs

Idiopathic hemorrhagic pericardial effusion was diagnosed in 8 dogs. The patients were typically males of large or giant breeds and a wide age range was represented. In all dogs clinical features of acute or chronic cardiac tamponade and right-sided heart failure were present. The pericardial effusion in each case was identified by thoracic radiography, electrocardiography, and echocardiography. Cytologic examination of the fluid did not allow differentiation from hemorrhagic effusions caused by neoplasia. Bacterial and fungal cultures were negative in 5 dogs. In 6 cases, a presumptive diagnosis was based on the absence of cardiac masses on 2-dimensional echocardiography, contrast pericardiography, or both. The condition was managed successfully by partial pericardiectomy in 5 cases. The definitive diagnosis in each case was established by gross cardiac examination at surgery or necropsy and by histologic examination of tissues. Blood vessels and lymphatics of the parietal and visceral pericardia appeared to be the primary targets of the disease process.     

Pericardial mesothelioma in a dog: long-term survival after pericardiectomy in combination with chemotherapy

A six-year-old male crossbred dog was presented with clinical signs of right-sided heart failure. Echocardiography demonstrated a pericardial effusion with cardiac tamponade, while pericardiocentesis and cytology did not reveal any evidence of malignancy. Pericardial drainage was performed twice over a period of three months to resolve haemodynamic impairment before a subtotal pericardiectomy was performed. Biopsy of parietal and visceral pericardium confirmed the diagnosis of pericardial mesothelioma. Intrathoracic cisplatin combined with intravenous doxorubicin were administered, although neutropenia, mild azotaemia and alopecia were noted as adverse reactions to these drugs. Intravenous cisplatin was repeated 45 days later after the signs of nephrotoxicity had resolved. The dog was still free of disease after 27 months. Intrathoracic chemotherapy after pericardiectomy and early diagnosis are recommended to improve prognosis, having achieved long-term survival in the present case.     

Idiopathic hemorrhagic pericardial effusion with organized thrombi in a dog

A dog was examined because of cardiac tamponade secondary to pericardial effusion. Masses adjacent to the right atrial and ventricular walls were revealed by echocardiography. Pericardectomy and biopsies of the masses established the diagnosis of idiopathic hemorrhagic pericardial effusion with organized thrombi. The dog was healthy 3 months after surgery. These organized thrombi mimicked cardiac neoplasia echocardiographically, and such a possibility should be included in the list of differential diagnoses of cardiac masses.     

Cardiac troponins I and T in dogs with pericardial effusion

Cardiac troponin I (cTnI) and cardiac troponin T (cTnT) are sensitive and specific markers for myocardial ischemia and necrosis. Dogs with pericardial effusion frequently have myocardial ischemia and necrosis, and these changes are more severe in dogs with hemangiosarcoma (HSA). We investigated the utility of using serum cTnI and cTnT concentrations to identify the idiopathic pericardial effusion from that associated with HSA. Blood samples for measurement of cTnI and cTnT concentrations were collected before pericardiocentesis in 37 dogs with pericardial effusion. Eighteen dogs had a mass consistent with HSA, 6 dogs had idiopathic pericardial effusion, 1 dog had mesothelioma, and 1 dog had a heart base tumor. No final diagnosis was achieved for 11 dogs. Dogs with pericardial effusion had significantly higher serum concentrations of cTnI (P < .001) but not cTnT (P = .16) than did normal dogs. Dogs with HSA had significantly higher concentrations of cTnI (2.77 ng/dL; range: 0.09-47.18 ng/dL) than did dogs with idiopathic pericardial effusion (0.05 ng/dL; range: 0.03-0.09 ng/dL) (P < .001). There was no difference in the concentration of cTnT between dogs with HSA and those with idiopathic pericardial effusion (P = .08). Measurement of cTnI may be useful in helping to distinguish between idiopathic pericardial effusion and pericardial effusion caused by HSA.     

Pericardial effusion in a dog with rhabdomyosarcoma in the right ventricular wall

A seven-year-old male labrador retriever presented in right heart failure with weak femoral pulses, and pleural, abdominal and mild pericardial effusion. No diagnosis could be established initially. Two days later, the dog developed severe pericardial effusion causing cardiac tamponade. A tumour in the right ventricular wall was visualised on ultrasonographic examination. An exploratory thoracotomy was performed and biopsies of the mass submitted for histopathological examination. A diagnosis of rhabdomyosarcoma arising from the myocardium was established. Cardiac rhabdomyosarcoma has been reported in only two dogs. Neither report was associated with pericardial effusion.     

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.     

Septic pericarditis in a Yorkshire Terrier

Objective: To describe a novel case management strategy for a small breed dog diagnosed with septic pericarditis. Case summary: An 8‐year‐old spayed female Yorkshire Terrier presented for evaluation of pericardial effusion and persistent hypoglycemia. The dog had been hospitalized at a primary care facility for acute onset of vomiting, lethargy, inappetance, and painful abdominal distension. Pericardial effusion was detected and upon referral, cytologic examination revealed a suppurative exudate with Gram‐positive and Gram‐negative bacteria. The dog was treated with pericardiocentesis and placement of an indwelling pericardial catheter. Subtotal pericardiectomy was performed and a thoracotomy tube was utilized postoperatively. A penicillin‐susceptible Bacteroides species was cultured from the pericardial fluid and was treated with a 6‐week course of antibiotics. The dog was discharged from the hospital and clinical signs have not recurred in over 2 years. New or unique information provided: Septic pericarditis, an uncommon cause of canine pericardial effusion, has been described primarily in large breed dogs and in association with bacterial infection secondary to Hordeum grass (foxtail) awn migration. This case was unique in that the dog was a small breed with no evidence of foreign body penetration or other precipitating cause for the pericarditis. In a novel management plan, an indwelling pericardial catheter was employed to stabilize the dog before subtotal pericardiectomy.     

Thoracoscopic Subphrenic Pericardectomy Using Double‐Lumen Endobronchial Intubation for Alternating One‐Lung Ventilation

Objective— To report the technique, complications, and effectiveness of thoracoscopic subphrenic pericardectomy (SPP) using double‐lumen endobronchial intubation for alternating 1‐lung (OLV) in healthy dogs. Study Design— Prospective cohort study. Animals— Mature purpose‐bred dogs (n=7). Methods— Bronchoscope‐assisted placement of a left‐sided double‐lumen endobronchial tube, immediately before surgery, allowed intraoperative alternation of ventilation between lung fields. A camera portal was established in a subxyphoid location. Two instrument portals were established at the 4th–6th intercostal spaces on the right and left sides. A vessel‐sealing device was used to create the subphrenic pericardectomy. After termination of the procedure, dogs were humanely euthanatized under anesthesia and necropsy performed. In each dog, the extent of pericardectomy and any complications were evaluated. Results— Technical difficulties with tube placement occurred in 4 dogs, but alternating OLV was achieved in all dogs and SPP completed successfully. Median surgical time was 87.5 minutes (range, 80–105 minutes). At necropsy, 0.5–2 cm of pericardial tissue remained ventral to the intact phrenic nerve in 6 dogs; in 1 dog, the phrenic nerve was transected on the left side only. Conclusions— Thoracoscopic subphrenic pericardectomy is a technically feasible procedure in healthy dogs. Double‐lumen endobronchial intubation allowed alternating OLV without intraoperative bronchoscopically guided tube manipulation in all but 1 dog. Clinical Relevance— Thoracoscopic subphrenic pericardectomy could potentially be used for management of conditions where relief of pericardial constriction or access to intrapericardial structures is desired.     

Thoracoscopic pericardiectomy: A feasibility study and impact on cardiac volumetry in healthy horses

This study was conceived to evaluate the feasibility of a thoracoscopic technique intended for partial pericardiectomy in horses and how cardiac volumes are influenced by such procedure in an immediate and mid-term perspective. Thoracoscopic pericardiectomy, which is known as a minimally invasive technique, was performed in six healthy horses. Echocardiographic evaluation was performed in every horse at different times, before and after the procedure. According to the area-length method, the following parameters were evaluated: maximum left atrial volume, minimum left atrial volume, left ventricular volume in systole and left ventricular volume in diastole. These variables were used to calculate the ejection fraction of the left atrium and left ventricle. After 28 days, repeated thoracoscopy was performed to inspect the thoracic cavity. Pericardiectomy was successfully performed in all horses, with post-operative complication documented in only one animal. After 28 days, adhesion was observed in two animals, located between the epicardium and the thoracic wall, without however impairing cardiac function. Pericardial window was broad and well delimited in all horses, without impairing cardiac function. The thoracoscopic pericardiectomy was feasible in all horses. Although a mild reduction in cardiac volumes was documented in the first 72 h after surgery, the procedure did not impair cardiac filling and emptying in the mid-term perspective. Future studies are warranted to investigate how this technique performs in horses with pericardial diseases.     

A retrospective study of clinical findings, treatment and outcome in 143 dogs with pericardial effusion

A retrospective study of 143 dogs with pericardial effusion is presented, including a statistical analysis of survival time. Cases were classified into those in which a mass was seen on echocardiography (echo-positive) and those in which no mass could be identified (echo-negative). Forty-four dogs were echo-positive and 99 were echo-negative. The median survival time (MST) was 1068 days for echo-negative dogs and 26 days for echo-positive dogs. Dogs with a history of collapse were more likely to present with a mass on echocardiography. Those presenting with collapse had an MST of 30 days compared with 605 days for those without collapse. Echo-negative dogs tended to present with ascites and generally had a larger volume of pericardial effusion. The median survival for dogs presenting with ascites was 605 days compared with 45 days for those without ascites. Among echo-negative dogs, 64 per cent had a relapse of their effusion. Subtotal pericardiectomy was performed in 31 echo-negative dogs. The procedure had a perioperative mortality of 13 per cent but provided a favourable long-term prognosis. Dogs undergoing pericardiectomy had a median survival of 1218 days compared with 532 days for those not undergoing surgery.     

Long-term survival of 23 dogs with pericardial effusions

Twenty-three dogs with pericardial effusions were identified from case records made between 1992 and 2000. Fourteen of the 23 were diagnosed with idiopathic pericardial effusions, and three of these were treated successfully by one pericardiocentesis. In the remaining 11 cases the pericardial effusion recurred; six cases were managed long-term by either two (three cases), three (two cases), or 11 repeated pericardiocenteses, and the remaining five were treated by pericardiectomy. The median survival time of the six dogs treated by repeated pericardiocentesis was five years and nine days.     

Therapeutic pericardiocentesis in the dog and cat

Pericardial effusion is a potentially life-threatening problem leading to a rise in the intrapericardial pressure resulting in varying degrees of hemodynamic compromise. Cardiac tamponade occurs when the intrapericardial pressure equals or exceeds right ventricular diastolic filling pressures leading to a decreased cardiac output. In dogs, the most common causes of pericardial effusion that require pericardiocentesis are cardiac neoplasia and idiopathic pericardial effusion (IPE). The incidence of cardiac neoplasia in dogs is low, and it is rare in cats. In dogs, hemangiosarcoma and chemodectoma are the two most common types of cardiac neoplasia. In cats, lymphosarcoma is the most common form of cardiac neoplasia, but they are more likely to develop pericardial effusion secondary to congestive heart failure or feline infectious peritonitis. Common histories include lethargy, dyspnea, anorexia, collapse, and abdominal distension. Pericardiocentesis is used to stabilize animals with life-threatening cardiac tamponade, relieve the pressure leading to right-sided heart failure, and obtain fluid samples for diagnostic evaluation. The fluid should be quantified and characterized. Serious complications associated with pericardiocentesis are rare. Complications include cardiac puncture, arrhythmias, and laceration of a tumor or coronary artery resulting in intrapericardial hemorrhage or sudden death.     

Alteration of ventricular function on echocardiography associated with intra-pericardial disorder in dogs

Two dogs with severe exercise intolerance (Cases 1 and 2) and another dog with cardiac dilation (Case 3) were referred to the Nihon University Animal Medical Center (ANMEC). Case 1 was diagnosed as pericardial effusion (PE), Case 2 as pericardial hemorrhage, and Case 3 as pericardiophrenic hernia. When these causative disorders were removed, the heart expanded, and clinical symptoms markedly improved in these three dogs. In particular, the cardiac chamber diameters and left ventricle fractional shortening (LVFS) was normalized in all 3 dogs postoperatively. There is only one case report that compares before effusion extractions in the pericardial sac with the after echocardiography findings. In this paper, echocardiography was conducted on the three endocardial disease cases, comparing before removing these causative disorders with the findings after echocardiography.     

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.     

DIAGNOSTIC PNEUMOPERICARDIOGRAPHY IN DOGS WITH SPONTANEOUS PERICARDIAL EFFUSION

To evaluate the diagnostic accuracy of pneumopericardiography, diagnostic pneumopericardiograms from 39 dogs with spontaneous pericardial effusion of various etiologies were reviewed. Diagnoses were confirmed by surgical biopsy, necropsy, or follow-up evaluation. Thirty-two of 39 studies (82%) were considered diagnostic. There were one false-positive and six false-negative studies. Fifteen of 16 studies (94%) in dogs with idiopathic sanguinous pericardial effusion were negative (i.e., similar to those in normal dogs). Seven of 12 right atrial hemangiosarcomas (58%), six of six heartbase neoplasms (100%), and two of two pericardial cysts (100%) were outlined. Studies in two cases of infective pericarditis revealed abnormal findings, while a negative study was obtained in one patient with pericardial mesothelioma. Lateral positions were most valuable in idiopathic effusions and for outlining heartbase neoplasms. The left lateral recumbent position was particularly important for outlining hemangiosarcomas. Pericardial cysts were profiled best in ventral or dorsal recumbent positions. This study documents the high diagnostic potential of technically adequate pneumopericardiograms in the etiologic diagnosis of pericardial effusion in the dog.     

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.