Impact of preload changes on positive and negative left ventricular dP/dt and systolic time intervals: preload changes on left ventricular function

Indian Heart J. 2012 May-Jun;64(3):314-8. doi: 10.1016/S0019-4832(12)60095-9.

Abstract

Aim/objectives: Previous work has shown that the electromechanical activation time (EMAT) is prolonged in patients with abnormally low left ventricular (LV) dP/dt. In the present study, we investigated whether EMAT was responsive to rapid changes in LV systolic function induced by abrupt increases in LV preload.

Methods and results: A total of 116 patients were assessed before and after LV angiography with a bolus injection of 40 mL of non-ionic contrast dye. Left ventricular end-diastolic pressure (LVEDP) increased from 18 ± 7 mmHg to 20 ± 8 mmHg (P < 0.01). In patients with a baseline dP/dt < 1500 mmHg/sec, dP/dt increased from 1098 ± 213 mmHg/sec to 1146 ±306 mmHg/sec (P=0.02) and EMAT decreased from 106 ± 29 ms to 103 ±18 ms (P=0.02). In patients with a baseline dP/dt > 1500 mmHg/sec, dP/dt decreased from 1894 ± 368 mmHg/sec to 1762 ± 403 mmHg/sec (P=0.01) and EMAT increased from 88 ± 13 ms to 93 ± 16 ms (P=0.02). Changes in negative dP/dt were similar to changes in dP/dt.

Conclusion: Electromechanical activation time is a non-invasively measured parameter that allows accurate and rapid detection of changes in LV contractility.

Publication types

  • Clinical Trial

MeSH terms

  • Adult
  • Aged
  • Contrast Media
  • Coronary Angiography
  • Female
  • Humans
  • Male
  • Middle Aged
  • Radionuclide Ventriculography
  • Systole / physiology
  • Ventricular Dysfunction, Left / diagnosis*
  • Ventricular Dysfunction, Left / physiopathology
  • Ventricular Function, Left / physiology*
  • Ventricular Pressure / physiology*

Substances

  • Contrast Media