Exercise stress echocardiography in the identification of coronary artery disease in the elderly with chronotropic incompetence.

BACKGROUND

Chronotropic incompetence (CTI) is frequent in elderly patients and may limit the role of the exercise test in the identification of coronary artery disease (CAD) in this population.

OBJECTIVE

To assess the value of CTI in an elderly population in the diagnosis of CAD.

METHODS

A total of 3,308 patients were studied, 804 were elderly individuals (age > 65 years) who underwent exercise stress echocardiography (ESE). Based on the heart rate (HR) reached during the exercise test, were divided into two groups: G1 150 patients who did not reach 85% of the age-predicted HR, and G2 654 patients who did. The groups were compared to clinical characteristics, segmental left ventricular contractility rate (WMSI) and coronary angiography (CAG).

RESULTS

Clinical characteristics were similar between the groups. WMSI was higher in G1 than in G2, both at rest (1.09 +/- 0.21 versus 1.04 +/- 0.15) and after exercise (1.15 +/- 0.29 versus 1.08 +/- 0.2) (p < 0.001). Abnormalities in wall contractility were more frequent in G1 than in G2 (55% versus 37%; p < 0.05), thus suggesting that elderly with CTI have a higher frequency of CAD. CAG was performed in 69% ESE positive for myocardial ischemia. In the G1 group, 91% of the ESE were true positive versus 84.5% in G2, that is, presence of obstructive coronary artery disease (> 50%).

CONCLUSION

CTI is associated with a higher frequency of contractile alterations in the elderly population and adds a positive predictive value to ESE in the identification of patients with obstructive CAD.