Being able to repair a heart artery without opening the chest seemed unrealistic. For the first time, an American team achieved a minimally invasive coronary artery bypass graftingperformed by catheter, without saw or broken sternum. At the center of this world first, a 67-year-old patient, too fragile to withstand open heart surgery.
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coronary artery bypass grafting requires opening the thorax, stopping the heart and connecting it to extracorporeal circulation. When angioplasty with stent is no longer sufficient, this operation remains the reference. But an American team today describes another route, totally percutaneous.
A patient without recourse to open surgery
The 67-year-old patient followed in Atlanta presented with a severely narrowed artificial aortic valve and very advanced heart failure, in a heart already operated on. He suffered from end-stage renal failure on dialysis and severe leg artery disease with recent amputation. Additionally, due to calcium buildup, this prosthesis now needed to be replaced. However, this patient’s particular anatomy placed the orifice of his left coronary artery so close to the valve that vital blood flow risked being obstructed during a traditional valve procedure.
“Our patient had an extensive history of procedures, vascular disease, and other confounding factors, making open-heart surgery completely impossible. In a case like this, having a minimally invasive alternative is essential“said cardiologist Adam Greenbaum in a statement from the NIH.
Due to several anatomical particularities, the patient could not benefit from existing minimally invasive solutions either. Fortunately, Doctors Greenbaum and Vasilis Babliaros of Emory University had recently set out to develop a solution specifically suited to this type of situation.
VECTOR, percutaneous coronary artery bypass grafting
Faced with this impasse, teams from the Emory School of Medicine and the National Heart, Lung and Blood Institute (NHLBI) chose the technical VECTOR
(“Ventriculo‑coronary transcatheter outward navigation and reentry”), until now only tested in animals. Using catheters inserted into the artery and vein of the thigh, they passed a wire from the left coronary artery to a heart chamber, then retrieved it through the vein to create an internal “rail”.
On this rail, operators then drilled two small openings, one in the aorta, the other in the wall of the coronary artery, and then deployed a stent. They passed the two free ends of this stent through each of the ports, then, as in the previous phase, connected them to create a new bridge, this time carving out a safe path for the bypass. Using this second wire, the team inserts a coronary artery bypass graft through the two new openings. Once in place, the graft creates a new blood circulation route, protected from risks.
“Achieving this required thinking outside the box, but I believe we have developed a very practical solution“, said lead author of the study Prof. Christopher Bruce, interventional cardiologist.
An experimental world first
Six months after the operation, the patient showed no signs of blockage of the coronary arteries, thus confirming the success of the first application of the VECTOR technique in humans. Although additional clinical trials are required before VECTOR is widely adopted, the team remains confident that success will continue following this significant advancement.
“It was extremely gratifying to see this project come to fruition, from its conception to animal testing to its clinical translation, quite quickly. Few places in the world can move as quickly and efficiently as at NIH in collaboration with our partners at Emory“Bruce said.
The researchers believe this new method could also be useful in the broader treatment of coronary heart disease, particularly in situations where other methods, such as implanting stents, fail to keep the arteries clear.