Left ventricular stroke work reserve as prognostic marker in severe heart failure
L La Vecchia1, L Varotto, G L Spadaro
1Department of Cardiology, S. Bortolo Hospital, Vicenza, Italy. luigilavecchia@libero.it
Minerva Cardioangiologica
|June 17, 2006
Summary
In severe heart failure, dobutamine stress testing using Swan-Ganz catheterization identifies patients with better survival. A positive response, indicating improved cardiac function, predicts a lower one-year mortality rate.
Area of Science:
- Cardiology
- Heart Failure Research
- Hemodynamics
Background:
- Severe heart failure is characterized by uniformly depressed cardiac function.
- Prognostic stratification in these patients is challenging.
- Current hemodynamic parameters often fail to predict survival accurately.
Purpose of the Study:
- To evaluate the utility of invasive hemodynamic assessment with dobutamine stress testing for prognosis in severe heart failure.
- To determine if stroke work reserve (SWR) can stratify risk in patients with depressed cardiac function.
Main Methods:
- 31 patients with severe heart failure underwent baseline hemodynamic evaluation via Swan-Ganz catheterization.
- Scalar doses of dobutamine were administered to assess changes in stroke work index (SWI) and calculate stroke work reserve (SWR).
- Patients were categorized as responders (SWR above median) or non-responders (SWR below median), with one-year follow-up.
Main Results:
- Dobutamine significantly increased SWI, with a median SWR of 6.4 g/beat/m2.
- A smaller left ventricular end-diastolic volume was the sole predictor of dobutamine response.
- One-year transplant-free survival was 47% in responders versus 0% in non-responders (P=0.007).
Conclusions:
- One-year mortality in severe heart failure remains high.
- Dobutamine stress testing reveals a subgroup with significantly lower mortality, identifying a positive response as an independent predictor of survival.
- This response is more probable in patients with less dilated left ventricles, offering a novel prognostic marker.
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