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Ann Thorac Surg 2003;76:811-816
© 2003 The Society of Thoracic Surgeons

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Original article: cardiovascular

Comparison of open subxiphoid pericardial drainage with percutaneous catheter drainage for symptomatic pericardial effusion

^a Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, St. Louis, Missouri, USA

^* Address reprint requests to Dr Meyers, Washington University School of Medicine, Division of Cardiothoracic Surgery, 3108 Queeny Tower, One Barnes-Jewish Hospital Plaza, St. Louis, MO 63110-1013, USA.
e-mail: meyersb{at}msnotes.wustl.edu

Presented at the Forty-ninth Annual Meeting of the Southern Thoracic Surgical Association, Miami Beach, FL, Nov 7–9, 2002.

	Abstract

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BACKGROUND: The optimal therapy for symptomatic pericardial effusions remains controversial. This paper compares outcomes after the two most commonly used techniques, percutaneous catheter drainage and operative subxiphoid pericardial drainage.

METHODS: We performed a 5-year retrospective, single-institution study to analyze outcomes after either percutaneous catheter drainage or subxiphoid open pericardial drainage for symptomatic pericardial effusions.

RESULTS: Symptomatic pericardial effusions in 246 patients were treated by open pericardiotomy and tube drainage (n = 150) or percutaneous catheter drainage (n = 96). Drainage duration, total drainage volume, and duration of follow-up (2.6 years) were similar in both groups. Effusions were classified malignant in 79 (32%) patients and benign in 167 (68%) patients. No direct procedural mortality occurred, but the hospital mortality was 16 patients (10.7%) in the open group and 22 (22.9%) in the percutaneous group (p = 0.01) The 5-year survival rate was 51% in the open group versus 45% in the percutaneous group, despite a greater percentage of the open group having a preoperative malignant diagnosis (35% versus 28%). Symptomatic effusions recurred in 16.5% of the percutaneous group compared with 4.6% in the open group (p = 0.002), and sclerosis did not appear to reduce recurrence rates (10.7% with sclerosis versus 15.6% without; p > 0.05). The diagnosis of malignancy was confirmed in 16 of 27 (59%) percutaneous procedures performed on patients with known malignancy. In the open group, cytologic and pathologic evaluation of the pericardial specimen revealed malignancy in 32 of 52 (62%) patients with known malignancy.

CONCLUSIONS: Subxiphoid and percutaneous pericardial drainage of symptomatic pericardial effusions can be performed safely; however, death occurs from underlying disease. Open subxiphoid pericardial drainage with pericardial biopsy appears to decrease recurrence but does not improve diagnostic accuracy of malignancy over cytology alone.

	Introduction

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The optimal treatment of symptomatic pericardial effusions remains controversial. Ideal treatment would include complete drainage of the effusion with no recurrence, obtaining adequate diagnostic material to allow for treatment of the underlying disease, and causing minimal morbidity and procedural mortality. Several procedures have been utilized to treat symptomatic pericardial effusions, beginning with the subxiphoid approach first described by Larrey in 1829 [1]. The treatment options summarized recently include systemic chemotherapy, local radiotherapy, pericardiocentesis, pericardial catheter placement with or without sclerosis, percutaneous balloon pericardiostomy, operative subxiphoid drainage with or without pericardioperitoneal window, pleuropericardial window (by thoracotomy or thoracoscopy), and pericardiectomy [2]. No prospective studies have evaluated the efficacy of these various techniques, and there is no consensus on treatment failure or success. Additionally, because patients with malignant pericardial effusions have a median survival of 2.2 to 3 months, the assessment for and the impact of recurrence in this subset of patients is limited [3, 4]. In addition, there is a tendency among referring physicians to assume that cytology coupled with parietal pericardial biopsy enhances diagnostic sensitivity. This would suggest that open pericardial drainage with pericardial biopsy would improve the diagnostic yield for pinpointing the underlying conditions responsible for the effusion.

Open drainage has the potential benefit of resecting a portion of the anterior central diaphragm and creating a chronically open channel between the pericardium and peritoneum. The open approach also allows the surgeon an opportunity to break up loculations with a finger or a suction device, place a much larger drainage tube, and possibly enhance drainage and stimulate adhesions between the epicardium and pericardium. Conversely, percutaneous drainage usually can be accomplished without the negative respiratory and hemodynamic effects of general anesthesia. As a result of these mixed attributes, there is widespread disagreement among surgeons and referring physicians as to the ideal procedure for a given patient.

The present study compared outcomes of patients treated with percutaneous pericardial catheter drainage with outcomes after open subxiphoid pericardial drainage. The variables compared include procedural mortality rate, early and late patient survival rates, estimated diagnostic sensitivity, and freedom from recurrence of effusions requiring additional treatment.

	Material and methods

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Patients
From January 1995 to December 1999, 246 patients with clinical and echocardiographic evidence of tamponade underwent treatment of their effusion at Barnes-Jewish Hospital in St. Louis, Missouri. This retrospective study was reviewed and approved by the Washington University Human Studies Committee (HSC #00-1118, 1/10/01). The choice of procedure was determined in many cases by the cardiologist performing the echocardiogram. If the echocardiogram suggested that the effusion was mostly posterior and inferior without a clear percutaneous trajectory for catheter drainage, the patient was typically referred for open drainage. Other patients referred from outside hospitals were treated by the accepting physician. There were no protocols or care paths in place during the study period that would have dictated treatment allocation. All patients included in this study underwent either open subxiphoid pericardial drainage (n = 150) or percutaneous pericardial catheter drainage (n = 96) as an initial procedure. The demographic characteristics of the patients are shown in Table 1.

Pericardial sclerosis was used in 19 patients with underlying malignancy. Thiotepa (15 mg diluted in 50 mL of normal saline) was instilled in the pericardium when chest tube output was less than 100 mL per day. This technique was used by one surgeon based on personal preference.

The technique of percutaneous pericardial catheter drainage utilized an 8-cm, 18-gauge angiocatheter. When the pericardial sac was entered, the angiocatheter was advanced and the needle withdrawn. A guide wire was then advanced through the catheter followed by a 60-cm, 8-F pigtail catheter. The pericardium was drained, and fluid was submitted for culture and cytologic analysis. The pigtail catheter was placed to gravity drainage and was flushed as necessary. Echocardiography or fluoroscopy guidance was used during catheter placement in all cases.

The timing of tube removal after either technique was dictated by the wishes of the responsible attending physician. There was no protocol or criterion, simply a decision on the part of the attending physician that additional drainage was no longer necessary. Pericardial drains were not managed differently in cases in which thiotepa was used.

Statistical methods
Actuarial survival and freedom from reintervention were calculated using the method of Kaplan and Meier [6]. Comparison of survival data was performed by the log-rank test. Two-sample t test and Fischer exact test (two tailed) were used to compare continuous variables. Statistical differences were considered significant if the probability was 0.05 or less.

	Results

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Two hundred forty-six patients underwent 271 procedures. Two hundred twenty-four patients underwent one procedure, 20 underwent two procedures, and one each underwent three and four procedures. One hundred thirty patients were female (53%), and 116 were male (47%), with age ranging from 16 to 91 years and a mean of 56 years. Patient characteristics, treatment characteristics, and etiology by treatment group is shown in Table 2. Etiology was presumed to be malignant if an underlying malignancy had been diagnosed and no other cause could be elicited. The etiology was benign in 167 patients (68%) and malignant in 79 patients (32%). The distribution of malignancies is shown in Table 3.

Direct procedural complications for the percutaneous catheter drainage group included one right ventricular laceration and two pneumothoraces. The ventricular laceration required open repair through a sternotomy, and the two pneumothoraces were treated with tube thoracostomy. The only intraoperative complication associated with the open subxiphoid drainage group was a single episode of ventricular fibrillation requiring defibrillation. No patient died as a direct result of either procedure; however, the hospital mortality rate was 22 of 96 (23%) in the catheter drainage group and 16 of 150 (11%) in the open subxiphoid drainage group (p = 0.01). The primary causes of death in the 22 patients who died after percutaneous catheter drainage included metastatic cancer in 8 patients, sepsis or infection in 6 patients, heart failure in 3 patients, hepatic failure in 2 patients, pulmonary failure in 2 patients, and intractable neurosarcoidosis in 1 patient. The causes of death in the 16 patients who died after open subxiphoid drainage included heart failure in 5 patients, metastatic cancer in 5 patients, sepsis or infection in 4 patients, stroke in 1 patient, and renal failure in 1 patient. The small sample sizes in each category and the diverse nature of associated morbid conditions make any comparison of modes of death between treatment groups impracticable.

The overall Kaplan-Meier actuarial survival plot by treatment type is depicted in Figure 1. One-, three-, and five-year actuarial survival rates were 56.3%, 48.9%, and 44.6% for the catheter drainage group and 64.0%, 56.6%, and 51.1% for the open group, respectively (p = 0.12). For patients with underlying malignancy, median survival was 119 days, and 31.6% percent survived 1 year.

View larger version (17K): [in this window] [in a new window]   Fig 1. Actuarial survival plot of treatment groups by the Kaplan-Meier method. Numeric percentages survival on curve represent 1, 3, and 5 years. Open drainage (black line; n = 150) = subxiphoid pericardiostomy; catheter drainage (gray line; n = 96) = percutaneous pericardial catheter drainage. p = 0.12 by Mantel.

View larger version (15K): [in this window] [in a new window]   Fig 2. Freedom from reintervention for recurrent pericardial effusion by the Kaplan-Meier method. Numeric percentages on curve represent 6 and 12 months. Open drainage (black line; n = 150) = subxiphoid pericardiostomy; catheter drainage (gray line; n = 96) = percutaneous pericardial catheter drainage. p less than 0.001 by Mantel.

	Comment

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The present study included a large group of contemporaneous patients for direct comparison of the two most commonly performed procedures for drainage of symptomatic pericardial effusions. Despite the limitations of the study, including nonrandom assignment, lack of standardized treatment or follow-up, and inability to assign pretreatment risk stratification, some conclusions can be made.

We found an association between the use of open subxiphoid drainage and a decreased recurrence of pericardial effusions requiring treatment. This association exists despite the slight predominance of malignant effusions in the open drainage group and the fact that malignancy was a predictor of recurrence. This is evident in the 1-year actuarial freedom from recurrence rate of 95% in the open subxiphoid group and 81% in the percutaneous catheter group. This finding is similar to those of previous studies. Allen and associates [3], for example, studied the recurrence rate of pericardial catheter drainage compared with open subxiphoid drainage in a retrospective study and found a 30% rate for percutaneous drainage and 1.1% for subxiphoid pericardiostomy. Several other studies have addressed this same issue; however, the studies often described a single method of drainage and did not include a direct comparison of these two modalities. Percutaneous catheter drainage in reported series resulted in a recurrence rate of 0% to 30%, with a combined rate of 16.2% [3, 4, 7–10]. Open subxiphoid drainage in published reports resulted in a recurrence rate of 0% to 9.1%, with a combined rate of 3.2% [3, 4, 11–21].

The potential for increased mortality from general anesthesia as the procedure is performed at our institution was not observed. No direct procedural mortality occurred in either group, and few complications occurred. The hospital mortality rate was higher in the percutaneous group. Despite few complications and generally good success in both groups, mortality was high from other causes. Preoperative evaluation of disability was not assessed from the hospital records in this retrospective study. Survival was shortest for patients with underlying malignancy, and the open drainage group had a higher fraction of patients with this etiology.

The importance of confirmation of malignancy in the pericardial fluid or tissue is underscored by the marked reduction in survival if cytologic or pathologic confirmation is achieved. The detection of malignancy and the observed association with poor outcome would allow for better prognostic information to be communicated to the patient. In patients with underlying malignancy, cytologic confirmation of malignancy in pericardial effusions ranges from 50% to 79% [4, 22–24]. Some reported rates of cytologic sensitivity warrant further discussion. In at least one series, the patients were not considered to have a malignant pericardial effusion unless cytology or histology was positive for pericardial malignancy [25]. By excluding all patients who had malignancy-associated pericardial effusion with negative cytology, selection bias was introduced. It is not known how many of the reported series summarized by Press and associates [24] had this selection bias. Recent reports have shown that cytologic confirmation of malignancy with pericardial drainage is only 50% sensitive; however, this study did not evaluate the improvement in detection of malignancy by use of pericardial biopsy [4]. Previous studies have shown a combined sensitivity of 55% for pericardial biopsy or pericardiectomy, with the poor sensitivity possibly related to location of the pericardial implants with metastases [26–28]. Fraser and colleagues [25] described the pathway by which malignancies invade the mediastinal lymph nodes followed by retrograde spread to the epicardial lymphatic channels. This would explain the low sensitivity of parietal pericardial biopsy, as lymphatic channels are few in this layer. We found a 46% (24 of 52) incidence of positive pericardial biopsy in the open subxiphoid drainage group, however, only 7% (4 of 52) had negative cytology. Although there is a small, incremental improvement in diagnostic yield by combining cytology with pericardial biopsy, these data suggest that cytologic evaluation of the aspirated fluid can be used to diagnose most malignant effusions. The lack of additional diagnostic yield of open pericardial biopsy versus fluid drainage alone makes the selection of the open procedure for enhanced diagnostic purposes a questionable strategy.

In this study we compared the two most commonly performed techniques of pericardial drainage in patients with symptomatic pericardial effusions. Both procedures had limited direct procedural mortality or complications; however, recurrence was significantly less likely in the subxiphoid open drainage group. Although either procedure could be used effectively, specific circumstances favor one of the procedures. For patients with positive cytology on previous pericardiocentesis, lifespan is so limited that recurrence is unlikely, so percutaneous pericardial catheter drainage could be recommended. Subxiphoid pericardiostomy may be the recommended treatment for patients with effusions in inaccessible posterior locations. Similarly, patients going to the operating room for other reasons may be best treated with open drainage, but the current study does not speak to that question.

	Discussion

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DR JOSEPH I. MILLER (Atlanta, GA): I very much enjoyed your presentation. I would just raise two potential questions. First, in your patients with malignant pericardial effusion, were the majority of these from lung cancer or were they from other causes?

Second, we have done the same thing you have done in utilizing the subxiphoid approach, particularly for lung cancer; however, when there has been a malignant effusion from breast cancer, lymphoma, or leukemia, we have used a limited parietal pericardiectomy through the left thorax, because those patients tend to survive much longer than the ones with lung cancer. Also, the mortality from doing the subxiphoid is almost zero to four or less, unless the patient is just too sick.

Pen Faber pointed out a number of years ago in a paper at the Society of Thoracic Surgeons that if one was going to use a subxiphoid approach, one should leave the catheter in probably 4 to 5 days, which showed in your presentation here the duration of drainage, because he believed that would make it scar down. So I think the technical point about leaving the catheter in for 4 to 5 days is important.

DR McDONALD: Thank you, Dr Miller, for the comments. First, our patient population was similar but somewhat skewed towards lung cancer in that 53% of our patients had lung cancer, 14% had lymphoma, and 7% had breast cancer. We did not have any mesotheliomas, and those are typically the fourth most frequent diagnosis with malignant effusions. Because of the predominance of lung cancer in our group we could not show a difference in survival benefit. People in the past have shown that breast cancer, as you alluded to and several others have, has better survival over lung cancer and some of the other more difficult cancers to treat. We have not performed parietal pericardiectomy as an adjunct to drainage, however. Certainly with the groups that have a longer survival it is a potential application.

DR JOHN M. KRATZ (Charleston, SC): I enjoyed your paper. I think that nearly all of us in the room would certainly agree with your thoughts and observations. Perhaps your paper might be better published in Circulation than the Annals of Thoracic Surgery, where the message needs to be sent.

One observation, most of us but perhaps not all of us in the room have found that Blake drains are comfortable for the patient and enable them to leave the hospital faster, and they allow, as Dr Miller alluded to, for longer drainage periods because patients can go home with them, perhaps cutting down on recurrences.

DR CHRISTOPHER J. KNOTT-CRAIG (Oklahoma City, OK): I enjoyed your paper as well and I would like to ask you one thing. I was unclear in your presentation, are you making a fenestration in the pericardium and draining that externally, or are you fenestrating the pericardium into either the pleural space or the peritoneum to try and prevent the recurrence of the effusions?

DR MCDONALD: There were no pericardiopleural windows in any of these cases. There were some pericardioperitoneal windows performed, but I think it has been shown in other studies that they do not remain patent for an extended period of time. That was a small subset of this group, but I suspect that in reality the duration of drainage caused symphysis of the visceral and parietal pericardium. As other people have shown in autopsy series, that is the more important factor.

	References

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This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): Jerome M. McDonald Bryan F. Meyers Richard J. Battafarano Joel D. Cooper G. Alexander Patterson Permission Requests Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by McDonald, J. M. Articles by Patterson, G. A. Search for Related Content PubMed PubMed Citation Articles by McDonald, J. M. Articles by Patterson, G. A. Related Collections Pericardium