ST segment depression in hypertensive patients: a comparison of exercise test versus Holter ECG

Abstract

Introduction: This study compared ST segment depression (ST depression) during cycle ergometry (ergometry) versus simultaneous 24-hour ambulatory blood pressure measurement and electrocardiogram recording (24-h ABPM/ECG) during everyday life.

Methods: In a German multicenter study, ergometry and 24-h ABPM/ECG records of 239 hypertensive patients were retrospectively analyzed. ST depression was defined as an ST segment depression (1 mm limb or chest recordings V1 to V6) in an incremental cycle ergometry, or 1 mm in the 24-h ABPM/ECG recording under everyday conditions. Blood pressure parameters at the onset of ST depression in the context of the respective method were compared.

Results: 18 patients had ST depression only in ergometry (group B), 23 had ST depression only during 24-h ABPM/ECG monitoring (group C) and 28 patients had ST depression with both methods (group D). Group A had no ST depression with any method. In group D, at the onset of ST depression with 24-h ABPM/ECG investigation, all parameters except diastolic blood pressure were significantly lower compared with the corresponding parameters at the onset of ST depression with ergometry (systolic blood pressure: 148 +/- 19 vers 188 +/- 35 mmHg, p < 0.001; heart rate: 93 +/- 12 vs 120 +/- 21 beat/min, p < 0.0001; double product: 13,714 +/- 2315 vs 22,992 +/- 3,985 mmHg/min), p < 0.0001).

Conclusion: ST depressions during everyday life detected by 24-h ABPM/ECG are characterized by a substantially lower triggering threshold for blood pressure level parameters compared with ergometry. The two methods detecting ischemia do not replace but complement each other.

Keywords: ST segment depression; arterial hypertension; blood pressure measurement; combined 24-h ABPM/ECG.

Figure 1

An excerpt from the 24-hour daily profile of a patient with poorly controlled isolated systolic arterial hypertension (the black bars show the systolic and diastolic blood pressure values and the cross-hatched curve shows the heart rate) (a). Electrocardiogram (ECG) lines with two independent bipolar leads at the beginning of the CardioTens monitoring (b). The ECG unit registered an ST depression episode at 8.20 a.m. that complied with the 1-1-1 rule (c). This triggered an additional blood pressure measurement by the 24-h ambulatory blood pressure measuring unit of the device (marked with a bar in a). The systolic (syst.), diastolic (diast.) blood pressure, pulse pressure (PP) mmHg, heart rate (HR) 1/minute, and double product (DP) mmHg/minute in the ST event are compared with the 24-h means table.