Video-thoracoscopic pericardial drainage in the treatment of pericardial effusions

Objectives: To assess efficacy and safety of videothoracoscopic pericardial drainage in the treatment and diagnostic of pericardial effusion through 26 cases review. Methods: From April 2005 to December 2007, 26 patients with pericardial effusion underwent a video-thoracoscopic pericardial window. Median age was 48.2 years old. Dyspnea was the most frequent symptom followed by thoracic pain. The procedure was performed in lateral decubitus, under general anesthesia and selective intubation with the aid of three trocars. Results: Procedure accomplish was feasible in 25 cases. One conversion occurred. In 61.53% of the cases the procedure was able to modify the initial diagnosis. Microbiology and tissue culture were negative in all cases. Neoplasia was present in nine cases, tuberculosis in two, aspergillosis in one, postoperative heart surgeries in three; lupus in two, uremia in one and idiopathy in eight. Associated pleuropulmonary procedures were performed in four cases. No deaths related to the procedure occurred. One late recurrence was recorded. Conclusion: The procedure is feasible, safe, reproducible and allowed an etiologic diagnostic. Specific treatment could be initiated in some cases. The intervention could possibly be the new gold standard treatment of pericardial effusion in selected patients. Descriptors: Pericardium. Thoracic surgery, videoassisted. Pericardial effusion/surgery. Resumo Objetivos: Analisar a eficácia e a segurança da drenagem pericárdica videotoracoscópica no tratamento e diagnóstico etiológico dos derrames pericárdicos por meio da revisão de 26 casos. Métodos: De abril de 2005 a dezembro de 2007, 26 pacientes com derrame pericárdico foram submetidos ao procedimento. A média etária foi de 48,2 anos. O sintoma mais comum foi dispnéia, seguida por dor torácica. O procedimento foi realizado em decúbito lateral, sob anestesia geral e intubação seletiva, com o auxílio de três trocateres. Resultados: A realização do procedimento foi possível em 25 casos. Ocorreu uma conversão. Em 61,53% dos casos, o procedimento foi capaz de alterar o diagnóstico inicial. Culturas e microbiologia foram negativas em todos os casos. São Paulo Medical School. Rua Borges Lagoa 10807o. and. Vila Clementino São Paulo SP. CEP 04038-000 Correspondence address: Diego Gaia. Disciplina de Cirurgia Cardiovascular Rua Napoleão de Barros 715 3o Andar Vila Clementino São Paulo SP. CEP: 04038-000. E-mail: drgaia@uol.com.br Article received on April 3rd, 2008 Article accepted on November 3rd, 2008


INTRODUCTION
The pericardial effusion is a relatively frequent disease, and is related to infectious processes (tuberculosis, viral, fungal and bacterial), metabolic (uremia, induced by drugs, hypothyroidism and rheumatoid arthritis), radiation and cancer.Thus, the etiologic diagnosis of effusion becomes crucial.Many of these patients present associated pleural disease [1].
In addition, the pericardial effusion may have other etiologies that require cultures and/or specific histopathological exams.
Despite pericardial puncture and pericardial drainage using catheter are effective in relieving of symptoms and cardiac tamponade, these methods do not present the same efficiency of surgical drainage in recurrent and septate effusion, nor allow appropriate collection of material for biopsy [1 ].
In these cases, surgical drainage performed by subxiphoid approach is able to promote symptomatic relief through pericardial cavity decompression and allows collection of pericardial fluid for analysis.Unfortunately, the collection of biopsies is limited to the small area approached, thus reducing the diagnostic possibility.Moreover, the incidence of recurrence may reach 10% in some series [2][3][4].
The lateral thoracotomy can also be used, allowing wide access to the pericardial cavity, but without much possibility of appropriate pleural inspection and with more postoperative pain and slower recovering [3].
The video-thoracoscopic pericardial drainage is a little invasive method used in the diagnosis and treatment of traumatic and non-traumatic pericardial effusion [5].It allows a wide examination of the thoracic cavity and the pericardium, with excellent visualization of mediastinal and thoracic structures, unlike the subxiphoid window that allows only viewing and limited pericardial resection.In the procedure, it is possible to create a wide pleuropericardial window and theoretically able to reduce recurrences [6].

Conclusão: O procedimento demonstrou ser seguro,
There is no consensus on the best alternative in the treatment of these disorders, but several groups have reported favorable results by using thoracoscopic drainage [3,4].
The aim of this study is to analyze the efficacy and safety of video-thoracoscopic pericardial drainage in the treatment and diagnosis of pericardial effusion through the review of 26 cases performed in our Service.

METHODS
Between April 2005 and December 2007, 26 patients with pericardial effusion underwent video-thoracoscopic pericardial drainage by making pleuropericardial window, after written informed consent and approval of the Research Ethics Committee.In the aforementioned period, all patients of the institution with indication for pericardial drainagewithout exclusion criteria -underwent the procedure proposed.
The following inclusion and exclusion criteria were used: Under thoracoscopic vision all trocars were placed.The identification of mediastinal structures was performed, with particular emphasis on the phrenic nerve (Figure 2).Then a stretched region was selected, below the phrenic nerve, which was punctured using an endoscopic needle with collection of material for culture, biochemistry and cytology.Subsequently, the pericardium was trapped by endoscopic forceps and then a pericardial window was performed using a curved endoscopic scissors.(Figure 3).
The fragment measuring about 4-5 cm in diameter was removed, taken from the chest and sent for histopathological examination entirely.An endoscopic suction device was then used to discard all liquid contents of the pericardial sac in order to discard any pericardial adhesions from the heart.
A chest drain was introduced and fixed through the orifice of the lower trocar.(Figure 4).Bipulmonary ventilation was restored through alveolar recruitment under thoracoscopic vision and aid of Valsalva maneuver.Patients were awakened from anesthesia, extubated and sent to the heart surgery postoperative unit and then to the ward.
Data on the time of thoracic drainage, intra-and postoperative complications and recurrence were collected.The thoracic drain was removed when the daily drainage was less than 100 ml.
After hospital discharge, patients were referred to usual outpatient follow up.
7. Severe hemodynamic instability, defined by need for intravenous vasopressors for maintenance of appropriate tissue perfusion pressure.
In the group studied, 14 patients were female.The mean age was 48.2 years (15-84 years).The symptoms included: dyspnea (n=21 / 80.8%), chest pain (n=2 / 7.7%), heart failure (n=2 / 7.7%) and test finding (n=1 / 3.8%).All patients had echocardiographic diagnosis before the procedure, and five patients underwent additional examinations such as computed tomography or magnetic resonance imaging in active search for neoplastic processess, due to the high clinical suspicion and analysis of pleural diseases that may preclude the procedure.Of these, two showed signs compatible with neoplasia (lung and breast) and the other showed no new findings.Eight patients (30.7%) presented signs and symptoms of cardiac tamponade.None of the patients presented prior isolated pericardial procedures or presented hemodynamically unstable under diagnosis.
The procedure was performed in all patients in lateral decubitus position under general anesthesia and selective intubation of the contralateral lung (Figure 1).The side to be approached was selected by the following criteria: too large heart areas, right side; associated pleural effusion, effusion side; adhesions, contralateral side.
Three trocars (Thoracoport -Ethicon -USA) were positioned for introduction of optics (Olympus -Japan, 10mm, 30.) and endoscopic instruments (Ethincon Endosurgery -United States, curved scissors, grip tweezers, vacuum and dissection forceps ), one of 10 mm and two of 5 mm, located respectively in the fifth, fourth and sixth intercostal spaces in the middle (10 mm) and anterior (5 mm) axillary lines (Figure 1).
After insertion of the first 10mm trocar (optical), an inspection of the entire pleural cavity was performed in search for adhesions, effusions or signs of pleural diseases.

RESULTS
The satisfactory accomplishment of the procedure was possible in 25 cases.There was only one case of conversion to a mini-thoracotomy for increased intraoperative bleeding.
Four cases (15.4%) were emergently performed, or that is, with need for immediate accomplishment after diagnosis.The intraoperative variables are summarized in Table 1.
In four cases, concomitant procedures (pleural and/or lung biopsy) were performed.In 16 cases (61.5%), the left side was approached and in any case the bilateral approach was necessary.
Less intraoperative complications have occurred in three cases: nonsustained ventricular tachycardia, acute pulmonary edema and need for prolonged orotracheal intubation in a patient with chronic obstructive pulmonary disease.
There were no deaths related to the procedure.A mortality rate equal to 19.2% (n=5) was found in the late follow-up, and four cases by advancing of neoplastic disease and one by aspergillosis.
There was only one recurrence (initial diagnosis of effusion secondary to uremia).The follow-up was performed with serial clinical and echocardiographic assessment.

DISCUSSION
Pericardial effusion is a relatively common disease in medical practice and especially in cardiovascular surgery.Its treatment is sometimes considered simple, when it is only considered the occasional symptomatic relief.However, the conventional intervention is often unable to provide sustainable results with a low rate of recurrence and high rate of diagnosis [3].
As the correct diagnosis may influence treatment, the achievement of a sure diagnosis is essential in appropriate management of these patients.
The best method to diagnose and treat the pericardial effusions remains a controversial subject.In recent years, with the advancement of minimally invasive procedures in cardiovascular surgery, increased emphasis has been given to this approach and increasing reports have shown the efficacy, safety and reproducibility of the thoracoscopic procedure [4][5][6][7].
In addition to allow the drainage of pericardial effusions, the procedure is able to diagnose associated pleural processes that may be investigated and treated in the same The pre-and postoperative diagnosis are summarized in Table 2. Cultures and microbiology were negative in all cases.Two cases initially classified as of uremic origin showed to be neoplasms.Eight cases presented diagnosis of chronic nonspecific pericarditis.Three cases occurred in the heart surgery postoperative period, none of them under anticoagulation.operative time, making the invasive evaluation more complete.
In our experience, the procedure has shown excellent mediastinal and chest inspection ability, and may be performed on a safe and fast manner, as well as to provide elements that could change the diagnosis and, consequently, the specific treatment of some patients.Our sample was able to show the procedure's ability to provide etiologic diagnostic able to change the therapeutic guidance, even with a substantial increase in the number of tumors initially identified as idiopathic effusions.
Before the procedure, 14 patients were classified as patients with idiopathic -or for clearing -effusions.This number was reduced to eight after intervention, showing their ability of positively affect the diagnosis.
We excluded patients with pleural adhesions and traumatic effusions due to it is the team's initial experience with the procedure, thereby avoiding potentially complicating factors in its achievement.Some centers no longer consider these findings as contraindications to perform the video-thoracoscopy pleuropericardial window [5].
The follow-up of our study was comparable with other authors by confirming a low or no rate of recurrences, possibly by performing wide pleuropericardial windows [8][9][10][11].
The intervention also did no require use of high cost devices, since the trocars and forceps used were permanent surgical instruments as well as the video device, making viable the intervention in many centers with limited resources in our country.
The time for performing the procedure was relatively short, but higher than the previously reported for conventional procedures via the subxiphoid window [4].There was a clear learning curve, in which the first procedures were performed in larger time, not affecting, however, the number of complications related to it.
The video-thoracoscopic pericardial drainage proved to be a safe procedure, and reproducible with non-fatal intraoperative complications, which did not alter the final outcome.The complication rate was similar to that reported by Geissbuhler et al. [12], however, higher than the reported in other series of thoracoscopy and subxiphoid intervention and may possibly reflect differences in the groups studied and the experience of the team with the procedure [13,14].The intervention was effective in performing the diagnosis and treatment of pericardial effusions, and allows the accomplishment of associated pleural procedures.
The limitations of our study include the small number of patients, the absence of interventions in unstable patients and non-randomization based on the conventional procedure.

Table 2 .
Pre-and postoperative diagnosis Final appearance of the procedure.Thoracic drain positioned through the lower orifice