Robotic skeletonizing of the internal thoracic artery: is it safe?

Comparison of the internal thoracic artery flow dissected by video endoscopy or conventional technique

Purpose:

To compare the blood flow in the internal thoracic artery when dissected endoscopically in a conventional manner, in addition to develop a reliable experimental training model for the surgical team.

Methods:

Paired experimental study. Ten pigs were operated and had both internal thoracic arteries dissected, the right with a conventional technique and the left by video endoscopy. The main outcomes to be studied were flow, length, and time of dissection of each vessel.

Results:

Blood flow measurements were performed with mean heart rate of 100 ± 16 bpm and mean arterial pressure of 89.7 ± 13 mm Hg. The mean blood flow of endoscopic dissection of the internal thoracic artery was 170.2 ± 66.3 mL/min and by direct view was 180.8 ± 70.5 (p = 0.26). Thus, there was no statistically significant difference between the flows, showing no inferiority between the methods.

Conclusions:

The minimally invasive dissection of the internal thoracic artery was shown to be not inferior to the dissection by open technique in relation to the blood flow in the present experimental model. In addition, the model that we replicated was shown to be adequate for the development of the learning curve and improvement of the endoscopic abilities.

Internal mammary harvesting: Techniques and evidence from the literature

Coronary artery bypass graft (CABG) is one of the most commonly performed cardiac surgeries in the world. CABG using the internal mammary artery (IMA) remains the gold standard intervention for myocardial intervention in multivessel coronary artery disease. IMA harvesting can be performed with various techniques and approaches: pedicled vs skeletonized harvesting technique as well as approaches such as conventional sternotomy, robotic and endoscopic approaches. While each technique and approach have their respective advantages and disadvantages, evidence remains varied between cohorts. Traditionally, IMA has been used as an in situ conduit; however, IMA free grafts also provide satisfactory outcomes in certain situations. This literature review aims to explore the efficacy of different techniques and approaches of IMA harvesting and grafting. With evidence compiled, this will provide an overview of the complexity of CABG and locate gaps in current literature to direct future research.

Outcome of Robot-Assisted Bilateral Internal Mammary Artery Grafting via Left Pleura in Coronary Bypass Surgery

Studies are extremely limited for the investigation of the clinical outcome of da Vinci robot-assisted bilateral internal mammary artery (BIMA) grafting in coronary artery bypass grafting (CABG) surgery. This study aimed to explore the short-term outcome of da Vinci robot-assisted BIMA grafting through the left pleural space. Relevant data were collected from patients with multi-vessel coronary artery disease receiving two kinds of CABG: a group of patients receiving da Vinci robot-assisted CABG with BIMA grafting, and another group of patients receiving sternotomy CABG with BIMA grafting. Primary endpoints, which included cardiovascular and renal endpoints, were analyzed between the groups using the chi-square test, analysis of variance test, and Kaplan-Meier analysis. Compared with the conventional group (n = 22), the robotic group (n = 22) had a significantly longer operation time (12.7 ± 1.7 vs. 8.5 ± 1.5 hours; p < 0.01) and a marginally lower mean of serum creatinine at baseline (1.2 ± 0.3 vs. 2.0 ± 1.7 mg/dL; p = 0.04). Primary endpoints (5, 22.7% vs. 12, 54.5%; p = 0.03) and renal endpoints (1, 4.5% vs. 7, 31.8%; p = 0.02) at six months were significantly reduced in the robotic group compared with the conventional group. There were no differences in cardiovascular endpoints at six months between the groups (1, 4.5% vs. 0; p = 1.00). The data showed that da Vinci robot-assisted BIMA grafting was safe, with equal cardiovascular events and lowered renal events at six months, as compared to conventional sternotomy BIMA grafting, despite the longer procedure time. The short-term study suggests that da Vinci robot-assisted BIMA grafting may be considered a favorable surgical option for patients with severe coronary artery disease.

Robotic internal mammary lymphadenectomy: another possible minimally invasive approach to sampling lymph nodes in breast cancer patients

Internal mammary lymphadenopathy may develop in breast cancer patients with silicone implants. Differential diagnosis includes malignant recurrence, infections, inflammations and granulomatous deposit. We report a case of internal mammary lymphadenopathy, in a patient with the previous history of breast cancer, requiring a tissue diagnosis. We performed a Robotic lymph nodes dissection of the left internal mammary. Final pathology diagnosis was positive for silicone granulomatous lymphadenitis secondary to silicone breast implants inserted after mastectomy for breast cancer.

Defining the Learning Curve for Robotic-Assisted Endoscopic Harvesting of the Left Internal Mammary Artery

Objective

Robotic-assisted techniques are continuing to cement their role in coronary surgery, particularly in facilitating the endoscopic harvesting of the left internal mammary artery (LIMA), regardless of how the subsequent bypass grafting is performed. As more surgeons attempt to become trained in robotic-assisted procedures, we sought to better define the learning curve associated with robotic-assisted endoscopic LIMA harvest.

Methods

Between January 2011 and July 2012, a total of 77 patients underwent robotic-assisted minimally invasive direct coronary artery bypass surgery at our institution. The LIMA was harvested endoscopically in all patients, using standard robotic instruments, followed by direct grafting to anterior wall myocardial vessels via a small thoracotomy. Intraoperative times for various components of the procedure were collated and analyzed.

Results

The mean ± SD time taken to insert and position the ports for the robotic instruments was 3.9 ± 1.4 minutes. The mean ± SD LIMA harvest time was 31.8 ± 10.1 minutes, and the mean ± SD total robotic time was 44.2 ± 12.9 minutes. All time variables consistently continued to decrease as the experience of the operating surgeon increased, with the greatest magnitude of improvement being evident within the first 20 cases. The logarithmic learning curves for LIMA harvest time and total robot time during our entire experience were both calculated as 90%, correlating to an expected 10% improvement in performance for each doubling of cases completed.

Conclusions

Coronary surgeons can rapidly become proficient in robotic-assisted endoscopic LIMA harvest, with significant improvement in operative times evident within the first 20 cases completed. These data may be useful in designing appropriate training programs for newer surgeons seeking to gain experience in robotic-assisted coronary surgery.

Internal mammary silicone lymphadenopathy diagnosed by robotic thoracoscopic lymphadenectomy

Internal mammary lymphadenopathy can be caused by a variety of disease processes and is a difficult diagnostic dilemma. We report a case of internal mammary lymphadenopathy, in a patient with a significant history of malignancy, requiring a tissue diagnosis. Robotic thoracoscopic lymphadenectomy was used to facilitate excisional biopsy. Pathology was significant for silicone granulomatous lymphadenitis secondary to silicone breast implants inserted after mastectomy for breast cancer.

New instrument for robotic-enhanced skeletonized internal thoracic artery harvesting: triangular hook

OBJECTIVE

: The introduction of robotic surgery has generated innovations in minimally invasive coronary surgery, including instrumentation. We have developed a small instrument, named by us the Triangular Hook, that expedites robotic skeletonization of the internal thoracic artery and makes the procedure safer.

METHODS

: Bilateral skeletonized internal thoracic artery harvesting was performed in four dogs (weight, 22 to 36 kg), using the da Vinci surgical system (Intuitive Surgical, Inc, Sunnyvale, CA). One internal thoracic artery was harvested with the Triangular Hook; the other was harvested without it. Harvesting time was measured for each form of harvesting, with the data being reported as mean ± SD.

RESULTS

: All eight internal thoracic arteries were harvested successfully; they were patent at the end of harvesting. Significantly less time was required for the Triangular Hook (41.5 ± 2.8 minutes) than for harvesting without it (47.5 ± 3.9 minutes; P = 0.02).

CONCLUSIONS

: The Triangular Hook is practicable and safe in robotic skeletonization of the internal thoracic artery.

Robotic Endoscopic Left Internal Mammary Artery Harvesting: What Have We Learned After 100 Cases?

BACKGROUND

The development of robotic devices has recently offered the possibility of performing coronary artery bypass graft surgery (CABG) in a totally endoscopic way. An important step of this procedure is endoscopic harvesting of the left internal mammary artery (LIMA). It was the aim of our study to find factors influencing LIMA harvesting time and to describe the challenges associated with robotic endoscopic LIMA harvesting.

METHODS

From June 2001 to December 2005, a total of 100 patients underwent robotically assisted CABG. In all cases, the LIMA was harvested by using the robotic DaVinci device. Coronary artery bypass grafting procedures were completed through sternotomy, minithoracotomy, or in a totally endoscopic fashion.

RESULTS

The median LIMA harvesting time was 48 minutes (19 to 180). A significant learning curve was observed: y (min) = 151 - 26 x ln (x), x = LIMA takedown number, p less than 0.001. Takedown time decreased from 140 minutes in the first 10 cases to 34 minutes in the last 10 cases. There was no independent demographic factor that significantly influenced the LIMA harvesting time. The LIMA takedown time also showed no significant correlation with thorax dimensions. Injury to the LIMA occurred in 3 patients (6%) during the first half of the experience and in 1 patient (2%) during the second half (p = not significant).

CONCLUSIONS

Robotic-enhanced LIMA takedown is a prerequisite for totally endoscopic CABG. After passing through a significant learning curve, IMA takedown can be performed safely and within an acceptable time frame. Demography and chest size do not seem to influence IMA harvesting time. The rate of LIMA injuries is within the limits of conventional thoracoscopic harvesting.

Robotic cardiovascular surgery

Cardiovascular surgery has traditionally been performed through a median sternotomy, allowing the surgeon generous access to the heart and surrounding great vessels. Recently, less invasive methods have been developed to allow the surgeon the same amount of dexterity and accessibility to the heart, thus resulting in a paradigm shift in cardiac surgery. Originally, long instruments without pivot points were used, however; with the application of robotic telemanipulation systems that allow for improved dexterity, the surgeon is able to perform cardiac surgery from a distance not previously possible. In this rapidly evolving field, this article reviews the recent history and clinical results of robotics in cardiovascular surgery.

Robotic cardiac surgery

BACKGROUND

Cardiac surgery, traditionally conducted via median sternotomy, has been recently forwarded by progressively advanced technology facilitating sternal-sparing minimally invasive, access to the heart. Robotic systems, comprised of miniaturized surgical instruments mounted on long thin shafts with multiple degrees of range of motion coupled with a dual camera endoscope providing true three-dimentional high-magnification visualization have greatly propelled this field.

METHODS

The robotic system and the literature base pertaining to robotic cardiac surgery is reviewed in depth.

RESULTS

Robotic cardiac surgical procedures have been performed to repair and replace the mitral valve, bypass coronary arteries, close atrial septal defects, implant left ventricular pacing leads, and resect intracardiac tumors.

CONCLUSIONS

As minimally invasive and robotic surgical technology advances, so proceeds the spectrum of potential applications for robotic cardiac surgery.