Effect of Sustained Isometric Handgrip Exercise on Left Ventricular Performance

Abstract

Sustained isometric handgrip exercise was studied in 28 patients, 19 with and nine without catheterization evidence of heart disease. Significant increases occurred in left ventricular systolic and left ventricular end-diastolic pressures (LVEDP), heart rate, cardiac output, and cardiac index, with decreases in stroke volume and stroke index. When control and abnormal groups were compared, no differences could be demonstrated in systolic pressure or heart rate increases. However, the LVEDP increase in the abnormal subjects (9.7 ± 1.7) was significantly (P < 0.01) higher than in the controls (2.1 ± 0.7). In addition, cardiac index rose significantly (P < 0.025) in the controls (0.8 ± 0.2), but not (P < 0.1) in the abnormal subjects (0.2 ± 0.1). Conversely, there was a significant fall in stroke index in the abnormal (P < 0.005) but not in the control (P < 0.4) group. When work or stroke-work index-LVEDP relations were compared, the controls uniformly exhibited steep curves, whereas abnormal patients demonstrated curves that were either less steep or flat. ΔWork/ΔLVEDP ratio was [See Equation in PDF File]1.0 in the controls, with one exception, and [See Equation in PDF File]0.77 in the abnormal subjects, with one exception. The test was performed in less than 4 min and no adverse effects were observed. By virtue of its ease, simplicity, safety, and ability to distinguish normal and abnormal ventricular performance, sustained handgrip is a valuable new stress test.