Hypertension

Background

Hypertension (increased blood pressure) is a complex cardiovascular disorder which affects approximately 73 million Americans. Measurements of cardiac output (CO), systemic vascular resistance (SVR), and thoracic fluid content (TFC) can aid clinicians in the selection and optimization of diuretics, beta blockers, ACEs, and other pharmacological interventions for hypertensive patients.

Application

Hypertension is caused by elevations in CO, SVR, or both.1 Obtaining and using these parameters to treat patients has been shown to provide better blood pressure (BP) control, compared to standard care.2,3 The Hypertensive Treatment Algorithm has been developed based on the findings of Taler2 and Smith3. This algorithm suggests establishing a hemodynamic profile for each patient and drawing conclusions based on their cardiac index (CI), systemic vascular resistance index (SVRI), and thoracic fluid content (TFC). Based on the hemodynamic profile, the diagnostic implications will warrant optimal treatment options.

References

Publication Conclusions
1Ventura HO, et al. Hypertension as a Hemodynamic Disease: The Role of Impedance Cardiography in Diagnostic, Prognostic, and Therapeutic Decision Making. American Journal of Hypertension. 2005;18:26S-43S - CO and SVR identify patients with abnormal hemodynamics and may increase diagnostic sensitivity for those with borderline hypertension1.
- Fluid retention resulting from renal effects of anti-inflammatory medications may be recognized by changes in TFC/TFI1
2 Taler SJ, et al. Resistant Hypertension: Comparing Hemodynamic Management to Specialist Care. Hypertension, 2002;39:982-988 - Improves BP control 70% in resistant hypertension.2
- Noninvasive measurements may guide antihypertensive therapy more effectively than clinical judgment alone, for patients resistant to empiric therapy.2
- Noninvasive measurements of thoracic fluid volume (TFI) support occult volume expansion and guide diuretic dosing2.
3 Smith RD et al. Value of Noninvasive Hemodynamics to Achieve Blood Pressure Control in Hypertensive Subjects (The CONTROL Trial). Hypertension. 2006;47:769-775 - Systolic and diastolic BP reductions were greater in patients who’s treatments were guided by noninvasive hemodynamics than those whom had standard care (19±17 vs. 11±18mmHg and 12±11 vs. 5±12mm Hg, respectively)
4 Sanford et al. Use of Noninvasive Hemodynamics in Hypertension Management. American Journal ofHypertension. 2005;18:87S-91S - Noninvasive hemodynamics helps clinicians tailor a pharmacologic regimen to address each patient4.
- This approach may lead to fewer medication side effects and reduce the number of office visits required to achieve BP control4.