Minimally invasive cardiac surgery (MICS) is gaining popularity. For it to be performed through the smallest possible wound with the least number of incisions in the heart or aorta, the cannulations necessary for cardiopulmonary bypass must be done through peripheral sites, such as the groin and neck vessels. One of the most difficult skills to learn for the cardiac anesthesiologist is how to safely and efficiently position the coronary sinus (CS) catheter (Endoplege; Edwards Lifesciences LLC, Irvine, CA USA) required for retrograde cardioplegia administration. Currently, there are no good anatomical models to perfect this skill before providing anesthesia care for MICS. There are expensive computer-based transesophageal echocardiography (TEE) simulators and anatomical models being developed, but these are not yet commercially available for CS cannulation. We have been using the pulmonary artery catheter (PAC) as a training tool for learning how to visualize and manipulate a right-sided catheter into the CS ostium/CS body with TEE for patients undergoing a standard, full-sternotomy cardiac bypass case. We developed this approach as one of the teaching techniques that can be used in preparation to hone some of the necessary skills needed to place the Endoplege catheter for MICS without incurring added or excessive costs by using the Endoplege catheter during the initial training stages. We believe the skills necessary to place catheters into the CS with TEE guidance can be acquired with the relatively inexpensive PAC.
After institutional review board approval was received, the anesthesia records of all adult patients who underwent coronary artery bypass grafting (CABG) and/or valvular repair or replacement via a full sternotomy (non-MICS) from December 1, 2010, through March 31, 2011, were retrospectively reviewed. If a chart was not available on the date of review, it was skipped and was not sought for review again. The charts where a PAC was inserted into the right internal jugular vein as part of routine intraoperative care, and documentation of its use as a MICS training tool was noted, were selected for further review. If the time from visualization of the CS by TEE to CS cannulation by the PAC was documented, the case was included in the study. Patients who underwent MICS where excluded from the study. There were no additional exclusion criteria.
There were no identifiers collected. The only instrument used was a data collection sheet that included a case number (starting with 1 and advanced sequentially), practitioner level manipulating the catheter (experienced/unexperienced), age, height, weight, type of cardiac surgery, visualization of the CS, and PAC by TEE. Experienced practitioners where considered those who routinely inserted the Endoplege catheter into the CS as part of their management of MICS cases and have a high success rate placing it. Unexperienced practitioners included practitioners who had minimal to no experience with inserting catheters into the CS (have seen the catheter placed in the past and where placing it for the first time or those who have placed a few CS catheters in the past and their success rate has been poor). Unexperienced practitioners manipulated the CS catheter under direct supervision and guidance by an experienced practitioner. Also recorded were TEE views used, total time to insert the PAC into the CS ostium, failures, and any reason elicited for the failure.
There were a total of 322 cardiac surgery cases done between December 1, 2010, and March 31, 2011, at our institution. Eighty-two were MICS cases (25.5% of total case load), and 220 were patients who underwent CABG and/or valvular repair or replacement via a full sternotomy (non-MICS), representing 68.3% of the total operative volume. The rest of the volume included heart transplantations, ventricular assist devices, and aortic surgery (6.2%). We were able to retrospectively review the 220 charts that met the initial selection criteria. Fifteen charts were identified where the anesthesia record provided documentation of the use of the PAC as a training tool for CS catheterization under TEE guidance. There were four patients in whom the PAC was manipulated twice, generating a total of 19 PAC manipulations (Table 1). When used as a training tool, the Swan-Ganz catheter is manipulated only to obtain cannulation of the CS ostium and proximal CS body at most and never inflating the balloon to reduce any potential risks. Fifteen catheter manipulations were done by the two most experienced anesthesiologists, who were able to cannulate the CS in 14 of 15 manipulations. There were four cases where unexperienced practitioners manipulated the PAC: two of them were second year anesthesia residents, one was a cardiac anesthesiology fellow in training, and one was a cardiac anesthesiologist. The manipulation of the PAC is done by holding the PAC body very close to its entrance into the PAC introducer and slowly advancing and rotating as needed until the catheter is visualized in the right atrium and then guided with similar slow deliberate motions into the CS. The CS and the PAC were visualized by TEE in all 15 patients. The right atrium was poorly visualized 1 (6.6%) of 15 patients. The PAC was inserted into the CS in 17 (89%) of the 19 attempts. Of the successful 17 insertions, the average time required to insert the PAC into the CS was 180.8 seconds (range, 19–954 seconds; median, 107 seconds; and mode, 51.2 seconds). The time to insertion was measured from start of PAC manipulation to CS cannulation. The three unexperienced practitioners who were supervised by an experienced practitioner were able to insert the catheter into the CS in an average time of 49 seconds. Two of the three cases done by an unexperienced practitioner were followed by an insertion done by an experienced practitioner. The insertion time by the experienced practitioner took an average time of 24.5 seconds. The two unsuccessful cases took 303 and 726 seconds before deciding to stop trying.
The TEE views used during the PAC manipulation included only 0-degree views in 14 of 19, only bicaval view in 2 of 19, or both views in 3 of 19 manipulations. Coronary sinus cannulation was obtained using the 0-degree view 13 times, using the bicaval view 3 times, and using both views 1 time.
No comments can be made about any potential relationship between age, sex, height, weight or body surface area, and PAC visualization or CS cannulation because of the reduced sample size.
Coronary sinus cannulation by the surgeon for retrograde cardioplegia administration during non-MICS is routine practice in many centers in the United States and elsewhere. A few of the cannulas that are placed by the cardiac surgeon on non-MICS procedures are now placed by the cardiac anesthesiologist during MICS, including the CS catheter for retrograde cardioplegia administration (Endoplege). In addition, the anesthesiologists aid the surgeon with TEE imaging on the placement of other cannulas as well. Fluoroscopy was used initially during MICS as the primary imaging modality, but TEE has replaced it as the imaging modality of choice for MICS and has been used for coronary sinus catheter placement during MICS since 1998.1,2 Oxymetric PAC catheters have been guided into the CS with combination of TEE and real-time blood oxygenation, with sudden significant oxygenation value drop as indication of CS cannulation.3 Others have placed the PAC into the CS inadvertently only to find out by TEE or by surgical examination after the sternotomy in a case where TEE was not used.4,5 We have developed several teaching techniques to reduce the learning curve for placement of the CS catheter. One of the techniques involves using the PA catheter in non-MICS cases, where the practitioner manipulates the right-sided catheter in the heart and into the CS (Video, Supplemental Digital Content 1, http://links.lww.com/INNOV/A22). Nearly 100% of the cases at our institution at the time of the study had a PA catheter placed as part of the operative and postoperative management. For the 220 patients who underwent CABG and/or valvular repair or replacement via a full sternotomy (non-MICS), which represented 68.3% of the total operative volume for the period studied, only a small portion of them (15 cases, 6.8%) had documented evidence in the anesthesia record of the use of the PAC as a training tool for learning how to cannulate the CS ostium. This could reflect the lack of documentation of such PAC uses or lack of taking advantage of such an educational tool. When the PAC was used as an educational tool, we were able to show that it was easily visualized in the right atrium and inserted into the CS in a short period of time. In this experience of 19 PAC manipulations, successful insertion into the CS was achieved 89% of the time. There were two cases were the CS was not cannulated. In one case, after 303 seconds, the unexperienced practitioner (cardiac anesthesia fellow in training) stopped further attempts; the CS was then cannulated by an experienced practitioner after 215 seconds. In the other case, the right atrium was poorly visualized, which would explain the failure by the experienced practitioner. Cardiac anesthesiologists use TEE6,7 as the main imaging modality to cannulate the CS. Other methods such as fluoroscopy and intracardiac electrocardiographic signals can aid as well but are used mostly by cardiologists in the electrophysiology laboratory because most of their patients are not under general anesthesia. Fluoroscopy has sporadically been used by anesthesiologist for CS cannulation as well. The two main TEE views used for CS cannulation are obtained at 0 degrees as the echo probe is withdrawn from the transgastric window, just before the midesophageal four chamber is visualized (Fig. 1). The second view is obtained from a bicaval view and modifications of it (Fig. 2). Our data showed that the preferred view used for visualizing the CS was the 0-degree view (17 times), followed by a combined 0-degree and bicaval view (3 times), and then a bicaval view alone (2 times). Coronary sinus cannulation was obtained using the 0-degree view 13 times (76%), using the bicaval view 3 times (17%), and using both views 1 time (6%). The frequent use of the 0-degree TEE view reflects one of the author’s personal preference, as he did 11 of the 19 catheter manipulations, using the 0-degree view in all his cases. This high use of the 0-degree view could very well reflect our local practice, as many centers use the bicaval view as their main view.
Manipulation and placement of intracardiac wires and catheters are not without risks. Vascular and cardiac perforation, arrhythmias, and conduction abnormalities up to complete heart block are some of them. Coronary sinus cannulation shares all the above risks with the added risk of CS perforation and/or dissection. Implantation of biventricular pacers for cardiac resynchronization therapy provides the most complete view of the risks because of the large number of patients studied and shows a risk of CS perforation/dissection between 0.5% and 2.1%.8,9 Lebon et al,10 in a review of 95 CS catheter placement for MICS, found only one CS dissection managed conservatively. Our local experience of more than 700 CS catheter insertions over the last 5 years showed two (0.3%) CS-related major complications: one perforation requiring repair and one dissection not requiring intervention. The overall risk of cardiac perforation with the use of a Swan-Ganz catheter seems to be extremely low as demonstrated on a prospective observational study of 7150 cardiac surgery patients in whom 3750 Swan-Ganz catheters where inserted, with four (0.1%) major complications: one right ventricular free wall perforation, one catheter knot, and two pulmonary artery ruptures.11 It is possible that the use of TEE (and fluoroscopy as well) during Swan-Ganz insertion could not only serve to acquire TEE (and fluoroscopy) expertise on guiding and manipulating intracardiac catheters in preparation for MICS but could also potentially reduce the already very low risk of complications of Swan-Ganz insertion and confirming a proximal position in the main pulmonary artery or proximal right or left branches for patients undergoing cardiac surgery as opposed to a more distal position used in intensive care for the Swan-Ganz catheter.
The lesser column strength of the Swan-Ganz catheter could be a contributing factor of the very low incidence of cardiac chambers perforation compared with the Endoplege or other catheters used during biventricular lead placement and could potentially reduce the risk of injuries the novice trained on CS cannulation techniques could cause.
On the basis of our clinical experience and this retrospective data collection, we were able to show that the Swan-Ganz catheter can be used as a training tool to acquire and perfect some of the necessary skills to place catheters into the CS under TEE guidance. It is possible that the smaller diameter of the Swan-Ganz catheter used (7.5 French) compared with the Endoplege (9 French) could have influenced the short time needed to cannulate the CS in our study. It can be suggested that a catheter with a distal curvature similar to the native Swan-Ganz distal curve can facilitate the CS cannulation and that it is fairly easy to cannulate the CS in a patient with “normal” CS anatomy and good TEE CS ostial view. The Swan-Ganz catheter is a relatively inexpensive and widely available tool at any center that performs cardiac surgery that could be used to enhance echo and CS cannulation skills.
We thank Valerie Lisotto for her assistance on this article.
1. Applebaum RM, Cutler WM, Bhardwaj N, et al.. Utility of transesophageal echocardiography during port-access minimally invasive cardiac surgery. Am J Cardiol
. 1998; 82: 183–188.
2. Plotkin IM, Collard CD, Aranki SF, Rizzo RJ, Shernan SK. Percutaneous coronary sinus cannulation guided by transesophageal echocardiography. Ann Thorac Surg
. 1998; 66: 2085–2087.
3. Ishikawa Y, Miyashita T, Koide Y, et al.. A new technique for pulmonary arterial catheter insertion into coronary sinus using transesophageal echocardiography. Anesth Analg
. 2003; 97: 291–292.
4. Hanson EW, Hannan RL, Baum VC. Pulmonary artery catheter in the coronary sinus: implications of a persistent left superior vena cava for retrograde cardioplegia. J Cardiothorac Vasc Anesth
. 1998; 112: 448–449.
5. Matyal R, Mahmood F, Panzica P, et al.. Inadvertent placement of a flow-directed pulmonary artery catheter in the coronary sinus, detected by transesophageal echocardiography. Anesth Analg
. 2006; 102: 363–365.
6. Coddens J, Deloof T, Thendrickx J, et al.. Transesophageal echocardiography for port-access surgery. J Cardiothorac Vasc Anesth
. 1999: 13: 614–622.
7. Clements F, Wright SJ, Bruijn N. Coronary sinus catheterization made easy for port-access minimally invasive cardiac surgery. J Cardiothorac Vasc Anesth
. 1998; 12: 96–100.
8. Gras D, Bocker D, Lunati M, et al.. CARE-HF Study Steering Committee and Investigators. Implantation of cardiac resynchronization therapy systems in the CARE-HF trial: procedural success rate and safety. Europace
. 2007; 9: 516–522.
9. Linde C, Abraham WT, Gold MR, et al.. REVERSE Study Group. Randomized trial of cardiac resynchronization in mildly symptomatic heart failure patients and in asymptomatic patients with left ventricular dysfunction and previous heart failure symptoms. J Am Coll Cardiol
. 2008; 52: 1834–1843.
10. Lebon JS, Couture P, Rochon AG, et al.. The endovascular coronary sinus catheter in minimally invasive mitral and tricuspid valve surgery: a case series. J Cardiothorac Vasc Anesth
. 2010; 24: 746–751.
11. Bossert T, Gummert JF, Bittner HB, et al.. Swan-Ganz catheter–induced severe complications in cardiac surgery: right ventricular perforation, knotting, and rupture of a pulmonary artery. J Card Surg
. 2006; 21: 292–295.
This article describes the use of a Swan-Ganz catheter as a training tool to learn how to visualize and manipulate right-sided catheters into the coronary sinus under transesophageal echocardiography guidance. These coronary sinus catheters can be difficult to implant for inexperienced anesthesiologists, and this is a good way to shorten the learning curve, particularly in centers without a high-volume of minimally invasive procedures.
Coronary sinus catheter; Retrograde cardioplegia; Minimally invasive cardiac surgery; Swan-Ganz catheter
Supplemental Digital Content
Copyright © 2012 by the International Society for Minimally Invasive Cardiothoracic Surgery. Unauthorized reproduction of this article is prohibited.