Echocardiographic vs hemodynamic monitoring during isometric exercise in patients with coronary artery disease

Isometric exercise is able to induce myocardial asynergies in patients with coronary artery disease as demonstrated by noninvasive monitoring performed during stimulation.

In the present study, a combined echocardiographic and hemodynamic monitoring of left ventricular contractility has been conducted in order to verify, with invasive and noninvasive techniques, the ability of isometric exercise in inducing transient myocardial ischemic phenomena.

The study population was composed of 20 patients with angiographic evidence of significant coronary stenosis (> or = 50%), and 10 subjects with normal coronary angiograms. All 30 subjects admitted to the study underwent an isometric exercise stress during echocardiographic and hemodynamic monitoring of left ventricular contractility.

Nine out of 20 patients with coronary disease showed regional asynergy during the test (Group I). The remaining 11 patients showed normal myocardial contractility (Group II). None of the 10 control subjects showed mechanical signs of ischemia during the test. Left ventricular end diastolic pressure significantly increased in both Group I (10 +/- 2 to 24 +/- 4 mmHg) and Group II (12 +/- 3 to 26 +/- 3 mmHg) (p < 0.01) while it remained unchanged in the control group (9 +/- 2 to 13 +/- 2 mmHg; p = NS); dp/dt increase (% basal) was significantly higher in the control group (45 +/- 6%) than in either Group I (25 +/- 3%) or Group II (26 +/- 3%) (p < 0.01).

Isometric exercise was able to induce left ventricular asynergies due to regional myocardial ischemia. Hemodynamic contractility monitoring easily distinguished the control subjects from the patients with coronary disease but was not able to discriminate patients with handgrip-induced regional asynergy. Thus, the echocardiographic technique offers more detailed information about regional myocardial function than do the common hemodynamic contractility indexes.