Asian Cardiovasc Thorac Ann 2007;15:e33-e34
© 2007 Asia Publishing EXchange Ltd
Intra-aortic Filtration is Effective in Collecting Hazardous Materials
Carlos-A Mestres, FECTS,
Eduardo Bernabeu, MD,
Claudio Fernández, MD,
Andrea Colli, MD,
Miguel Josa, MD
Department of Cardiovascular Surgery, Hospital Clinico, University of Barcelona Barcelona, Spain
For reprint information contact: Carlos-A Mestres, MD Tel: 34 93 227 5515 Fax: 34 93 451 4898 Email: cmestres{at}clinic.ub.es, Cardiovascular Surgery, Hospital Clinico, Villarroel 170, 08036 Barcelona, Spain.
 |
ABSTRACT
|
|---|
Neurological complications after cardiac operations are mostly due to particle embolization. This case illustrates the embolic potential of any material. A 77-year-old lady underwent re-operation for homograft aortic regurgitation and mitral valve replacement. Intra-aortic filtration was used. After cardiopulmonary bypass the filter was found to have captured a pledget from a suture used to secure the mitral replacement device.
|
INTRODUCTION
|
|---|
Neurological complications seen after cardiac operations are probably the most devastating. Aortic atheroma, changes in the flow pattern during cardiopulmonary bypass, and concomitant intra- and extracranial cerebrovascular disease are among the well recognized influencing factors. It is difficult to accurately establish the actual incidence of Type I neurological events, including stroke, transient ischemic attacks, stroke, and coma but the available information confirms a 3% event rate.1
The only way to counteract the impact of neurological complications is prevention. In recent years, published reports address intra-aortic filtration.2–4 Intra-aortic filtration using a filter deployed in the aortic arch through the side port of a specially designed aortic return cannula (Embol-XTM Edwards Lifesciences, Irvine, CA, USA) seems to be effective in retrieving particles with potential embolic power. Recently published papers refer to a capture rate of 96.8 to 99%, citing atheromatous debris as the most frequently captured material,2 although fibrin, platelet aggregates, clots, and medical tissue have also been isolated. Patients undergoing a combined intracardiac procedure and coronary artery bypass graft appear to be at the highest risk for embolization of particulate debris.
Here we present the case of a patient in whom the intra-aortic filter was used as a routine part of the operation. Intra-aortic filtration retrieved a Teflon pledget from a suture used during mitral valve replacement (MVR).
|
CASE REPORT
|
|---|
A 77-year-old female patient underwent freehand cryopreserved aortic homograft implantation for calcific aortic stenosis and small aortic annulus in 1992. The homograft was implanted using multiple interrupted non-pledgeted 3/0 braided sutures. She was readmitted because of recurrent congestive heart failure in August 2004. Two-dimensional echocardiography and color-flow mapping disclosed severe mitral regurgitation with a calcified annulus, aortic regurgitation, and severe pulmonary artery hypertension (systolic pulmonary artery pressure > 60 mm Hg). She was re-operated on for mitral insufficiency and homograft regurgitation on August 19, 2004. Aortic root replacement with a homograft and mitral valve replacement with a bioprosthesis were performed. During the operation, an Embol-XTM intra-aortic filter was used as it is routinely used in high-risk cases for embolization at our institution. The filter dwell time was 15 minutes. After removal of the Embol-XTM intra-aortic filter, a Teflon pledget was found in the filter after the dwelling period (Figure 1
). The patient was successfully weaned off cardiopulmonary bypass.
She initially did well and was extubated after 20 hours showing no signs of neurological deficit. However, she later required re-intubation due to rapidly progressive respiratory failure secondary to pneumonia and near-systemic pulmonary artery hypertension. She eventually died two months later. The filter was sent for histological analysis.
|
DISCUSSION
|
|---|
Neurological complications after cardiac surgery with cardiopulmonary bypass are among its most devastating complications. Intra-aortic filtration has recently emerged as a promising tool for prevention as it is designed to capture particulate material.3,4 Previous experiences show that there is a trend towards a beneficial effect of this technique. The case presented herein clearly illustrates that filtration is effective in capturing any type of material that may proceed uncontrolled in the bloodstream.
The filter is composed of a 100µ net and therefore able to capture almost any kind of particle. The experience from the International Council of Emboli Management Study Group (ICEM),4 a large European registry that enrolled 1,400 patients, and the ICEM 2000 group from the United States was able to show that intra-aortic filtration is able to decrease postoperative neurological outcomes due to a largely embolic etiology.
What was of striking interest in this particular case was to find a felt pledget in the filter when the patient was weaned off cardiopulmonary bypass. Although the patient was initially successfully extubated, she eventually died as a result of a deteriorating respiratory condition and severe near-systemic pulmonary artery pressure. In this case it was shown that the patient had a normal neurological status that may have otherwise been harmed by the embolic potential of this pledget that originated from a suture used for mitral valve replacement.
Peripheral embolization during cardiac operations may reach any organ,3 however it is clear that brain embolization leads to the worst outcomes. Any material has embolic potential and this includes non-vascular material such as the pledget luckily captured in this case.
|
REFERENCES
|
|---|
- Roach GW, Kanchuger M, Mangano CM, Newman M, Nussmeier N, Wolman R, et al. Adverse cerebral outcomes after coronary bypass surgery. Multicenter Study of Perioperative Ischemia Research Group and the Ischemia Research and Education Foundation Investigators. N Engl J Med 1996;335:1857–63.[Abstract/Free Full Text]
- Harringer W. Capture of particulate emboli during cardiac procedures in which aortic cross-clamp is used. International Council of Emboli Management Study Group. Ann Thorac Surg 2000;70:1119–23.[Abstract/Free Full Text]
- Banbury MK, Kouchoukos NT, Allen KB, Slaughter MS, Weissman NJ, Berry GJ, et al; ICEM 2000 Investigators. Emboli capture using the Embol-X intraaortic filter in cardiac surgery: a multicentered randomized trial of 1,289 patients. Ann Thorac Surg 2003;76:508–15.[Abstract/Free Full Text]
- Wimmer-Greinecker G; International Council of Emboli Management (ICEM) Study Group. Reduction of neurologic complications by intra-aortic filtration in patients undergoing combined intracardiac and CABG procedures. Eur J Cardiothorac Surg 2003;23:159–64.[Abstract/Free Full Text]
TOP
ABSTRACT
INTRODUCTION
