Coronary collateral circulation in coronary artery disease and systemic hypertension. The extent and functional capacity of coronary collateral circulation in patients with systemic hypertension has not been elucidated. In the present study, 313 patients with coronary artery disease were studied to evaluate coronary collateral circulation in relation to the presence of systemic hypertension and left ventricular hypertrophy. Patients had greater than or equal to 95% diameter luminal obstruction of either the left anterior descending or the right coronary artery. Patients were classified into 2 groups: The hypertensive group consisted of 61 patients, mean age 55 +/- 9 years, with systemic hypertension, and the normotensive group consisted of 252 patients, mean age 53 +/- 8 years, without hypertension. The hypertensive group had more severe angina pectoris and less history of healed myocardial infarction than the normotensive group (p less than 0.001). Left ventricular wall thickness was 1.26 +/- 0.1 cm in the hypertensive and 1.03 +/- 0.06 cm in the normotensive group (p less than 0.001). The hypertensive group had more extensive coronary collateral circulation than the normotensive group (p less than 0.01). There was a positive relation between coronary collateral circulation and left ventricular wall thickness (p less than 0.001). These results indicate that patients with systemic hypertension and coronary artery disease have an increase in coronary collateral circulation corresponding to the degree of left ventricular wall thickness. 