Cardiology

Identifying chronic Heart Failure (HF) patients at increased near-term risk of recurrent decompensation

Evaluating the Stroke Index (SI) and Thoracic Fluid Content (TFC) of a chronic HF patients who recently experienced an episode of clinical decompensation can assist medical staff in determining the likelihood of the patient having a recurrent decompensation event.

If the patient has a SI > 35 ml · m-2 and Thoracic Fluid Content TFC = 35 they have a risk of less than 1% of a heart failure event as compared to a risk of 7% for high risk patients which have an SI = 35 ml · m-2 and a TFC > 35.

The Four Cardiocirculatory quadrants developed by Packer et al. can be used as a reference in assessing the near-term risk of a recurrent decompensation when using the EC monitors to obtain a hemodynamic assessment. The quadrants display a patient in the highest risk quadrant has seven times the risk of a recurrent decompensation as a patient in the low risk quadrant. [1]

Figure 1: The Four Cardiocirculatory quadrants [3]

Hypertension

The increase in mean arterial pressure displayed in arterial hypertension can be a result of an increase in Cardiac Output (CO), Systolic Vascular Resistance (SVR) or both. Obtaining a complete hemodynamic assessment from hypertensive patients using the EC monitors allows for differentiation of patients with elevated CO and those with elevated SVR. By determining the hemodynamic status of the patient, optimum antihypertensive treatment can be chosen more easily [2]. Goal directed therapy (GDT) has shown to provide proper blood pressure control in patients 70% more often than those who did not receive a hemodynamic assessment. Patients treated according to the GDT showed greater reduction in SVR was obtained and more intensive diuretics were used based on the level of TFC. [3]

Hemodynamic Assessment Anithypertensive Treatment
Increase in CO Beta blocker (propranolol)
Increase in SVR Calcium blocker (nifedipine)
Increase in TFC Diuretic

Potential Benefit: Early warning sign of the development of left ventricle failure (LVF)

One the first signals of the development of left ventricle failure is the deterioration in heart function [4]. Using the EC monitors, the contractility of the left ventricle and ejection fraction can be monitored using the Index of Contractility (ICON) or Systolic Time Ratio (STR). Observing an overall decrease in either value indicates deterioration in heart function.


[1] (Packer, 2006)

[2] (DL, 1996)

[3] (SJ, 2002)

[4] (Sodolski, 2007)