Outcome of coronary plaque burden: a 10-year follow-up of aggressive medical management

Abstract

Background: The effect of aggressive medical therapy on quantitative coronary plaque burden is not generally known, especially in ethnic Chinese.

Aims: We reasoned that Cardiac CT could conveniently quantify early coronary atherosclerosis in our patient population, and hypothesized that serial observation could differentiate the efficacy of aggressive medical therapy regarding progression and regression of the atherosclerotic process, as well as evaluating the additional impact of life-style modification and the relative effects of the application of statin therapy.

Methods: We employed a standardized Cardiac CT protocol to serially scan 113 westernized Hong Kong Chinese individuals (64 men and 49 women) with Chest Pain and positive coronary risk factors. In all cases included for this serial investigation, subsequent evaluation showed no significantly-obstructive coronary disease by functional studies and angiography. After stringent risk factor modification, including aggressive statin therapy to achieve LDL-cholesterol lowering conforming to N.C.E.P. ATP III guidelines, serial CT scans were performed 1-12 years apart for changes in coronary artery calcification (CAC), using the Agatston Score (AS) for quantification.

Results: At baseline, the mean AS was 1413.6 for males (mean age 54.4 years) and 2293.3 for females (mean age 62.4 years). The average increase of AS in the entire study population was 24% per year, contrasting with 16.4% per year on strict risk factor modification plus statin therapy, as opposed to 33.2% per year for historical control patients (p < 0.001). Additionally, 20.4% of the 113 patients demonstrated decreasing calcium scores. Medical therapy also yielded a remarkably low adverse event rate during the follow-up period --- 2 deaths, 2 strokes and only 1 case requiring PCI.

Conclusions: This study revealed that aggressive medical therapy can positively influence coronary plaque aiding in serial regression of calcium scores.

Figure 1

Flow Chart showing how patients were selected for entering the study.

Figure 2

This figure is typical of the Rate of Progression of Calcium Scores on Statin Usage. Statins produced a retarded Rising Trend in Calcium Scores compared to historical untreated Subjects. Ca = Calcium; Pt. = Patient

Figure 3

This figure is typical of the Rate of Regression of Calcium Scores on Statin usage plus Risk Factor Modification. Statins plus Life-style Modification regressed Coronary Plaques in some cases.