A characterized model of left ventricular hypertrophy in the rabbit.

A rabbit model of left ventricular hypertrophy is characterized with respect to blood pressure, heart mass and ventricular refractoriness. Hypertension and left ventricular hypertrophy was induced by unilateral nephrectomy plus wrapping of the contralateral kidney in cellophane. Control or sham operated animals were subjected to a similar procedure except that the kidney was not wrapped in cellophane. No change in conscious mean arterial blood pressure was shown in the 11 sham operated animals (75 +/- 2 mmHg before operation and 75 +/- 3 mmHg 4-5 weeks after). Mean arterial pressure was increased from 73 +/- 2 to 99 +/- 3 mmHg by 4-5 weeks and had reached a plateau of 110 +/- 3 mmHg 5-6 weeks after operation in the 16 animals in which the kidney was wrapped. The ratios of left ventricular dry weight to body weight and of whole heart wet weight to body weight were significantly (p < 0.05) higher in the wrap group (0.38 +/- 0.01 and 2.97 +/- 0.12, respectively) than in the sham group (0.29 +/- 0.01 and 2.44 +/- 0.08 respectively). Effective refractory period, recorded from the left side of the arterially perfused interventricular septum, was greater in the wrap (266.1 +/- 8.9 ms) than in the sham group (228.2 +/- 3.5 ms). Linear correlations were shown between mean arterial pressure or effective refractory period vs the ratio of left ventricular dry weight to body weight or ratio of whole heart to body weight. This study has shown that hypertension induced by perinephritis caused left ventricular hypertrophy which was associated with a prolongation in ventricular refractoriness in the rabbit.