Elevated arginine vasopressin and lowered atrial natriuretic factor associated with hypertension in coarctation of the aorta.

Impairment of humoral and neural regulation of blood pressure may contribute to preoperative and postoperative hypertension in coarctation of the aorta and may also affect the release of vasopressin and atrial natriuretic factor. Because vasopressin and atrial natriuretic factor have potent vasoactive effects, we measured plasma vasopressin and atrial natriuretic factor levels by radioimmunoassay before operation and for 5 days after operation in 11 patients aged 9 months to 12 years undergoing coarctation repair and in 12 control patients undergoing other cardiovascular operations. Six patients in the coarctation group required minimal antihypertensive therapy (group I) and five required prolonged intravenous antihypertensive therapy (group II). Before operation, vasopressin levels correlated with systolic blood pressure for all patients in the coarctation group (r = 0.83, p < 0.01) whereas atrial natriuretic factor levels did not. Before operation, atrial natriuretic factor levels were lower (28 +/- 5 vs 41 +/- 7 and 50 +/- 8 pg/ml, p < 0.05) and vasopressin levels were higher (28 +/- 6 vs 5.4 +/- 0.9 and 7 +/- 3 pg/ml, p < 0.05) in group II than in group I or control patients. Vasopressin levels were higher (p < 0.05) on the day of operation and on postoperative days 2 through 5 in group II than in group I and in control patients. Atrial natriuretic factor levels were lower during the day of operation in group II than in group I or in control patients (26 +/- 7 vs 51 +/- 16 and 50 +/- 7 pg/ml, p < 0.05) and remained lower than control values on postoperative days 1 and 3 through 5. Elevated vasopressin and lowered atrial natriuretic factor levels may contribute to preoperative and postoperative hypertension in coarctation.

A technique for placement of left atrial monitoring line.

A technique for placement of a left atrial monitoring line is described. Following repair of a complex congenital heart defect, a long catheter previously advanced from the common femoral vein or the saphenous vein into the right atrium is inserted across the interatrial septum through the parent foramen ovale or through a small incision in the atrial septum at the level of the fossa ovalis. A suture is placed to close the interatrial septum around the catheter. This technique has been used successfully for four years.

Technique of intraoperative placement of thermodilution catheter for cardiac output measurement in children.

A simplified solid thermodilution catheter has been used in 100 infants and children undergoing open heart surgery. The catheter is now available commercially. It is introduced into the main pulmonary artery through the right ventricular wall. The technique is simple, non-traumatic, speedy and has been without complications in 100 cases.