The J-curve relationship between diastolic pressure and coronary collateral circulation in patients with single chronic total occlusion

BackgroundIn our previous study, we had shown that high diastolic blood pressure (DBP) was positively related to well-developed coronary collateral circulation (CCC). This study sought to find out the more precise relationship between DBP and CCC.Methods and resultsTo investigate this, we conducted a study of 671 patients with single chronic total occlusion of coronary artery. The DBP of the patients was divided into six groups: ≤65 mmHg, >65-≤75 mmHg, >75-≤85 mmHg, >85-≤95 mmHg, >95-≤105 mmHg, >105 mmHg). The extent of CCC was graded as poorly-developed or well-developed collaterals according to Rentrop classification. There was a J-curve relationship between the level of DBP and the incidence of poorly-developed collaterals.ConclusionThe relationship between DBP and CCC is similar to the J-curve relationship between DBP and cardiovascular risk. The influence of DBP on the development of CCC may be one of the pathophysiologic mechanisms of the J-curve phenomenon relating DBP to cardiovascular risk.