The Role of Transesophageal Echocardiography During Port-Access Minimally Invasive Cardiac Surgery: A New Challenge for the Echocardiographer

Guidelines for the Use of Transesophageal Echocardiography to Assist with Surgical Decision-Making in the Operating Room: A Surgery-Based Approach: From the American Society of Echocardiography in Collaboration with the Society of Cardiovascular Anesthesiologists and the Society of Thoracic Surgeons

Intraoperative transesophageal echocardiography is a standard diagnostic and monitoring tool employed in the management of patients undergoing an entire spectrum of cardiac surgical procedures, ranging from "routine" surgical coronary revascularization to complex valve repair, combined procedures, and organ transplantation. Utilizing a protocol as a starting point for imaging in all procedures and all patients enables standardization of image acquisition, reduction in variability in quality of imaging and reporting, and ultimately better patient care. Clear communication of the echocardiographic findings to the surgical team, as well as understanding the impact of new findings on the surgical plan, are paramount. Equally important is the need for complete understanding of the technical steps of the surgical procedures being performed and the complications that may occur, in order to direct the postprocedure evaluation toward aspects directly related to the surgical procedure and to provide pertinent echocardiographic information. The rationale for this document is to outline a systematic approach describing how to apply the existing guidelines to questions on cardiac structure and function specific to the intraoperative environment in open, minimally invasive, or hybrid cardiac surgery procedures.

Anesthesia management of totally endoscopic atrial septal defect repair with a robotic surgical system

STUDY OBJECTIVE

To investigate anesthetic techniques for robot-assisted endoscopic atrial septal defect (ASD) repair.

DESIGN

Clinical observational study.

SETTING

Operating room of a general military hospital.

PATIENTS

56 adult, ASA physical status 1 and 2 patients undergoing elective general anesthesia.

INTERVENTIONS

After induction of general anesthesia, a left-sided, double-lumen endotracheal tube was positioned to allow single left-lung ventilation and contralateral CO(2) pneumothorax (capnothorax). With ultrasound guidance, peripheral cardiopulmonary bypass (CPB) catheters were placed.

MEASUREMENTS AND MAIN RESULTS

All patients tolerated single left-lung ventilation before CPB; however, hypoxia (oxygen saturation < 90%) occurred in 11 (19.6%) patients post-CPB, which required treatment with continuous positive airway pressure. Fifteen (26.8%) patients had hypotension secondary to capnothorax, which was treated with transfusion and vasopressors. Aortic cross-clamp time was 43.6 ± 11.2 minutes, and CPB time was 106.7 ± 12.4 minutes. The median intensive care unit stay was 21 hours and postoperative hospital stay was 4 to 7 days.

CONCLUSIONS

The key issue for anesthetic management of robot-assisted totally endoscopic ASD repair is maintaining stable hemodynamics and oxygenation, especially during one-lung ventilation and capnothorax.

Surgical, anesthetic, perfusion-related advances in minimal access surgery

As we enter the fifth decade in cardiac surgery, traditionally cardiac surgery has been performed using a median sternotomy with cardiopulmonary bypass providing great access to the heart and all the surrounding structures. During the last decade, there has been a paradigm shift in the methods by which surgery has been performed. The invasiveness of many procedures has been dramatically reduced, with significantly superior outcomes, as evidenced by improved survival, fewer complications, and quicker return to functional health and productive life. This resulted in significant interest and excitement in adopting less invasive techniques in cardiac surgery. Unfortunately, this was an unrealistic expectation due to the limitations that existed in cardiac surgical techniques and conventional endoscopic instruments, cardiac anesthesia, and cardiopulmonary bypass techniques. In this article, the advances in minimally invasive surgical, cardiac anesthesia, and cardiopulmonary bypass techniques in the evolution of minimal access cardiac surgery are summarized.

Embolic stroke due to a left atrial thrombus two years after placement of an atrial septal defect closure device

A 29-year-old woman who had undergone closure of a secundum-type atrial septal defect using the Amplatzer device 2 years previously developed acute and progressive altered mentation. Initial clinical and imaging data confirmed the diagnosis of multiple cerebral, cerebellar and brain stem emboli, and infarcts. She was treated urgently with an intra-arterial thrombolytic agent with only minimal improvement. Transesophageal echocardiography revealed a large thrombus attached to the left atrial disc of the atrial septal defect occluder, which was the source of the emboli. In conclusion, this is the first reported case, to our knowledge, of disseminated cerebral emboli and infarctions as a late complication of transcatheter closure of a secundum-type atrial septal defect.

Intraoperative Echocardiography in Minimally Invasive Cardiac Surgery and Novel Cardiovascular Surgical Techniques

Minimally invasive cardiovascular surgery has been developed in an effort to decrease hospital length of stay and cost by decreasing pulmonary and neurologic complications, pain, chest trauma, and infection. The smaller incisions provide less direct cardiac visualization and exposure, which makes transesophageal echocardiography an essential and integral part of these innovative procedures. Transesophageal echocardiography does not obstruct the surgical field and can perform a full evaluation of the heart. This includes assessment of the aorta and great vessels, valve function, ventricular wall motion, placement of catheters and cannulae, hemodynamic monitoring, and immediate evaluation of surgical results and complications.

Beating-heart mitral valve surgery: preliminary model and methodology

OBJECTIVE

It is our hypothesis that image-guided mitral valve repair can be performed on the beating heart without cardiopulmonary bypass. As a first phase, we tested the feasibility of suturing the anterior and posterior mitral valve leaflets under image guidance.

METHODS

In a water bath model, imaging approaches and suturing techniques were developed. Then, in 6 pigs, the left atrium was cannulated with a custom-made 15-mm valved port through a left thoracotomy. Atrial pressure was elevated by shunting of arterial blood to minimize air induction. A multiplane transesophageal echocardiographic probe was evaluated in the intraesophageal and epicardial positions. With a commercial endoscopic suturing device, sutures were placed through the anterior and posterior mitral leaflets under echocardiographic guidance. The animals were killed, and suture accuracy was evaluated by measuring the distance from the intended target areas on the anterior and posterior mitral leaflets. Air induction was monitored by echocardiography and graded as minimal to severe.

RESULTS

There were no cases of hemodynamic instability or significant arrhythmia. The most effective imaging plane was a short-axis view that used the transesophageal echocardiographic probe epicardially at the heart base. Air induction was minimal in 2 animals, mild in 3, and moderate in 1. Sutures were successfully placed 9 of 12 times (mean error 0.8 +/- 0.5 cm).

CONCLUSIONS

With these methods, off-pump, image-guided suturing of the beating-heart mitral valve was possible. This model may be a useful starting point for developing off-pump mitral valve repair procedures.

Anaesthesia for minimally invasive cardiac surgery

Minimally invasive cardiac surgery is used for both extracardiac and intracardiac procedures. Extracardiac procedures, such as coronary artery bypass grafting, are often performed on a beating heart. Intracardiac procedures are done with the aid of cardiopulmonary bypass. The surgery is performed via a minithoracotomy or a ministernotomy. Thoracoscopic video-assisted surgery, often with robotic assistance, necessitates prolonged one-lung ventilation to optimize exposure. Port-access surgery will require appropriate positioning of various catheters to establish cardiopulmonary bypass. Adequate flow during cardiopulmonary bypass may require suction augmentation of venous return and may increase the risk of air emboli. Limited exposure of the heart during surgery poses challenges with management of arrhythmia, haemostasis, myocardial protection and de-airing at the end of surgery. Patient selection is important to avoid intra-operative and post-operative complications. Prolonged single-lung ventilation, incomplete revascularization in hybrid procedures, and limited access for rapid intervention pose challenges with patient management. Conversion to sternotomy that may be required occasionally and extension of portals over several dermatomal segments mandate a versatile analgesic technique.

Minimally invasive aortic valve replacement: echocardiographic and clinical results

BACKGROUND

Port access has been described for mitral and bypass surgery. The purpose of this study was to review the clinical and echocardiographic outcomes of aortic valve replacement by use of port access.

METHODS

Between 1996 and 1999, 153 port-access aortic valve replacements were performed at our institution. The mean age was 63 years (range 16-91 years); 58% were male. The New York Heart Association mean class was III; 18% were in class IV. Thirteen percent had diabetes, 42% hypertension, 7% prior transient ischemic episode or stroke, 7% lung disease, 3% renal failure, and 13% previous surgery. Echocardiograms were obtained after valve replacement in 125 patients (96 intraoperative transesophageal and 97 transthoracic echoes).

RESULTS

Median length of stay was 8 days. There were no intraoperative deaths; 10 patients (6.5%) died in the postoperative period. Stroke occurred in 4 (2.6%), sepsis in 5 (3.3%), renal failure in 5 (3.3%), pneumonia in 3 (2%), and wound infection in 1 (0.7%). Tissue prosthesis was present in 83 and a mechanical prosthesis in 42. No or trace regurgitation was seen on 94 of 96 (98%) postbypass intraoperative echocardiograms and mild on 2. On follow-up echocardiograms, moderate regurgitation was seen in 4 of 97 (4.1%), mild-to-moderate in 2 (2.1%), mild in 18 (18.6%), and no or trace in 71 (73.2%). Of those who had aortic regurgitation on intraoperative or follow-up echocardiograms, it was paravalvular in 8.

CONCLUSIONS

Minimally invasive aortic valve replacement with a port-access approach is feasible, even in high-risk patients. Small incisions, a low infection rate, and a short length of stay are attainable. However, the complications associated with traditional aortic valve replacement still occur. Echocardiography is valuable both for intraoperative monitoring and follow-up of this new procedure.