Validation of local venous sampling within the at risk left anterior descending artery vascular bed in the canine left ventricle

Abstract

The validity of using blood sampled from the anterior interventricular vein (AIV), anatomically located within the myocardium perfused by the left anterior descending (LAD) coronary artery, to represent venous drainage originating from the LAD vascular territory was studied in eight anaesthetised, open chest dogs. The LAD was cannulated and perfused from a blood reservoir isolated from the systemic circulation. To determine the presence of blood from non-LAD sources that appears in the AIV sample, 51Cr-labelled red blood cells were injected into the left atrium and distributed in the systemic circulation while the LAD was perfused by non-radioactive blood. The percentage spillover of red blood cells from non-LAD sources into the AIV drainage was determined under control, reduced LAD flow, ischaemia, and reperfusion conditions as 100 X (AIV chromium content/arterial chromium content). Spillover of red blood cells into AIV blood samples averaged only 1.5(1.3)% under control conditions and increased insignificantly to 8.6(3.5)% during reduced LAD flow. During ischaemia red blood cells in AIV blood increased insignificantly to 98.3(5.0)% but decreased to 1.9(1.3)% after reperfusion. Studies in five dogs with microspheres showed that a portion of this admixture from non-LAD sources originated from precapillary nutritional collateral or overlapping blood flow.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of Inotropic Drugs on Mechanical Function and Oxygen Balance in Postischemic Canine Myocardium: Comparison of Dobutamine, Epinephrine, Amrinone, and Calcium Chloride

“…An 18-gauge catheter was inserted into the left atrium for the measurement of luminal pressure (Datex, Helsinki, Finland), and a 24-gauge catheter into the anterior interventricular vein at the same level as the LAD occluder for measurement of coronary venous oxygen and lactate concentrations (12). …”

Regulation of Coronary Blood Flow

“…In normal anatomy, anterior surface drainage is facilitated by the interventricular vein which is immediately adjacent to the LAD in the interventricular groove. Virtually all drainage from the anterior interventricular vein is derived from the LAD perfusion territory (711, 954). This drainage system continues into the great cardiac vein which courses along the anterior atrioventricular groove parallel to the circumflex artery.…”

“…Both major veins drain into the coronary sinus located in the posterior atrioventricular groove. Accordingly, venous blood within the coronary sinus is supplied by both the anterior (LAD) and posterior (circumflex) perfusion territories (196,711,796,954). Approximately 55% of the coronary arterial blood supply is returned to the sinus via these two anterior sources.…”

Hypoxic Conditioning Suppresses Nitric Oxide Production upon Myocardial Reperfusion

“…An electromagnetic flow probe (Transonic Systems model 2SB, Ithaca, NY) was placed on the LAD to monitor coronary flow, and a silk suture was passed around the LAD immediately distal to the flow probe, forming a snare. After heparin administration (500 U/kg) the interventricular coronary vein, which selectively drains the LAD perfusion territory (17), was cannulated to sample coronary venous blood. Body temperature was measured with an intramuscular needle probe placed in the quadriceps femoris and maintained at 36.5-37.5°C by a circulating H 2 O heating pad positioned under the dog.…”