Advantages of a modified gastroscope for video-assisted internal mammary artery harvesting

Non-Robotic Endoscopic-Assisted Internal Mammary Artery Harvest-A Historical Review and Recent Advancements

Background: The non-robotic endoscopic harvest of the internal mammary artery (IMA) facilitates minimally invasive bypass grafting while minimizing chest wall trauma. The technique was pioneered in the early 1990s and has recently regained popularity due to its accessibility and reproducibility. This review aims to provide an overview of endoscopic IMA harvest from its inception to the present. Methods: In August 2024, a literature search was performed using the electronic databases of the Cochrane Controlled Trials Register (CCTR) and PubMed. To obtain optimal search results, the keywords "thoracoscopic", "endoscopic", "minimally invasive", "video-assisted", "video-assisted thoracoscopic surgery VATS", and "internal mammary artery" or "internal thoracic artery" were used, excluding the term "robotic". References from the extracted articles were also reviewed to identify additional studies on endoscopic IMA harvest. Results: A total of 17 articles were included in the final analysis. Left internal mammary artery (LIMA) harvest times of between 17 and 164 min were reported, with an injury to LIMA rates between 0.7 and 2.2%. Conclusions: After a 15-year period without scientific publications, interest in the endoscopic-assisted approach has rekindled in recent years due to the reduction in chest trauma compared to direct vision harvest and the widespread availability of conventional endoscopic tools. This renewed focus underscores the potential to make minimally invasive coronary surgery available in all centers.

Minimally invasive and robotic coronary artery bypass grafting-a 25-year review

During the mid-1990s cardiac surgery started exploring minimally invasive methods for coronary artery bypass grafting (CABG) and has over a 25-year period developed highly differentiated and less traumatic operations. Instead of the traditional sternotomy mini-incisions on the chest or ports are placed, surgery on the beating heart is applied, sophisticated remote access heart lung machine systems as well as videoscopic units are available, and robotic technology enables completely endoscopic approaches. This review describes these methods, reports on the cumulative intra- and postoperative outcome of these procedures, and gives an integrated view on what less invasive coronary bypass surgery can achieve. A total of 74 patient series published on the topic between 1996 and 2019 were reviewed. Six main versions of minimal access and robotically assisted CABG were applied in 11,135 patients. On average 1.3±0.6 grafts were placed and the operative time was 3 hours 42 min ± 1 hour 15 min. The procedures were carried out with a hospital mortality of 1.0% and a stroke rate of 0.6%. The revision rate for bleeding was 2.5% and a renal failure rate of 0.9% was noted. Wound infections occurred at a rate of 1.2% and postoperative hospital stay was 5.6±2.2 days. It can be concluded that less invasive and robotically assisted versions of coronary bypass grafting are carried out with an adequate safety level while surgical trauma is significantly reduced.

Augmented venous return for minimally invasive open heart surgery with selective caval cannulation

OBJECTIVE

Minimally invasive open heart surgery involves limited intrathoracic cannulation sites necessitating cardiopulmonary bypass to be initiated via peripheral access using percutaneous cannulae with the tip placed into the right atrial cavity. However, surgery involving the opening of the right heart obliges the surgeon to maintain the end of the cannulae into the vena cavae. The impeded venous return due to the smaller diameter may be alleviated by inserting a centrifugal pump in the venous line.

METHODS

Right anterior mini-thoracotomy and exposure of the femoral site were performed before the patient was heparinized. Cannulation of the femoral artery, the inferior vena cava via the femoral vein and the superior vena cava through the mini-thoracotomy was performed and cardiopulmonary bypass was initiated. Venous drainage was augmented with the centrifugal pump. Cardiac arrest was provoked and both vena cavae were snared before performing the intracardiac procedure.

RESULTS

Twenty consecutive patients were operated on using this technique (15 males/five females; age: 44.8 +/- 14.3 years; bodyweight: 73.5 +/- 15.1 kg; body surface area: 1.8 +/- 0.2 m2; theoretical blood flow rate: 4.4 +/- 0.5 l/min). The cannula sizes were 21.9 +/- 2.2 Fr for the femoral artery, 26.5 +/- 1.7 Fr for the inferior vena cava and 23.8 +/- 2.5 Fr for the superior vena cava. Venous drainage through the single inferior vena cava cannula was 2.1 +/- 0.6 l/min (48.8 +/- 13.3% of the theoretical flow). Adding the superior vena cava cannula increased the venous flow to 3.1 +/- 0.4 l/min (70.7 +/- 9.6% of the theoretical value, P < 0.005). The use of the centrifugal pump increased the flow to 4.1 +/- 0.6 l/min (93.4 +/- 8.9% of the theoretical flow, P < 0.001) with a mean inlet negative pressure of -69 +/- 10.2 mmHg. The mean bypass time was 64.0 +/- 24.6 min for a mean operative time of 226.3 +/- 61.0 min. Minimum venous saturation was 69.4 +/- 8.5%.

CONCLUSIONS

Despite the smaller diameter of the vena cavae compared to the right atrium, and a smaller internal diameter of percutaneous cardiopulmonary bypass cannulae compared to classic ones; the centrifugal pump improves the venous drainage significantly so that minimally invasive open heart procedures can be performed under optimal and safe perfusion conditions.