A model of delayed aortic coarctation employing arterial and venous catheters for chronic blood sampling in conscious dogs.

We have developed a reproducible model of cardiac hypertrophy in conscious, unrestrained dogs after recovery from surgical trauma. The model has many potential applications due to the availability of non-stressful blood sampling from four arterial and/or venous vascular locations. Samples of blood for biochemical or pharmacological measurements were obtained from the carotid and femoral arteries as well as the pulmonary artery and inferior vena cava. Left ventricular hypertrophy up to 128% of the non-operated control animals was produced at 96 h post-intraluminal aortic coarctation. Inflation of a balloon in the descending aorta increased outflow resistance and resulted in hypertrophy. Hemodynamic parameters of cardiac function were obtained via a Swan-Ganz cardiac output catheter located permanently in the pulmonary artery. Complications observed in the dog model were minimal and mortality did not occur during the experimental period. This animal model employing multiple implanted catheters for blood sampling plus the ability to impose aortic coarctation in the unrestrained animal provides a flexible model system for biochemical and pharmacological research.