Abstract: In a method for locating an arterial constriction and performing an arteriotomy distally thereof, especially with a view to establishing a bypass connection between the aorta (52) and a part of the coronary artery (51) distally of a constriction in the artery, the most important steps are locating the site of the constriction in the artery (51), preferably by using an instrument (9) with a head (3) carrying an ultrasonic transducer array (not shown), and making an incision in the artery (51) closely distally of the constriction, preferably by using a knife (not shown) placed in said head (3).

Abstract: An end-to-side anastomosis between a first vessel (27) and a second vessel (51) is carried out using an anastomosis instrument comprising a tube (20) in which the first vessel (27) is inserted and everted at the end of the tube (20) to form a collar (28), a springy anastomotic fitting (30) with outwardly directed spikes (32) having previously been placed under elastic bending in a circumferential recess (22). The tube (20) is inserted in a previously made incision in the second vessel (51), a guide member (35) ensuring that the wall region (53) around the incision contacts the everted collar (28). Then, an ejector (23) is operated to liberate the fitting (30) from the recess (22), releasing the fitting to expand quickly, so the spikes (32) penetrate the collar (28) and the wall region (53). Finally, the tube (20) and the ejector (23) are removed, and so is the guide member (35) having previously been made to collapse in a manner not shown to allow it to be removed through the first vessel (27).

Abstract: A method of locating a constriction in a coronary artery and performing an arteriotomy distally thereof which comprises locating the site of a constriction in a coronary artery by scanning the artery with a non-invasive sensing instrument capable of detecting the constriction. The sensing instrument has associated therewith a cutting instrument comprised of a cutter and member for moving the cutter into a position for making an incision. After the constriction is located, the cutting member is moved into a cutting position distal of the constriction and an incision is made through the wall of the artery into the lumen thereof.