Diagnosing heart failure in aortic valve stenosis.
OBJECTIVE
In aortic valve stenosis (AS), heart failure (HF) omens a high risk of death and is an indication for prompt valve replacement. We studied whether its detection can be facilitated by measuring plasma N-terminal B-type natriuretic peptide (Nt-BNP) or by estimating pulmonary capillary wedge pressure (PCWP) using echocardiography.


METHODS
A cross-sectional cohort study in a university hospital.


METHODS
We studied 137 consecutive adult patients referred to our unit for invasive evaluation of isolated AS. All patients underwent cardiac catheterization, measurement of plasma Nt-BNP and estimation of PCWP by Doppler echocardiography of transmitral and pulmonary venous flow velocities. The final diagnosis of HF was based on the combined criteria of dyspnoea on ordinary effort and PCWP >14 mmHg at cardiac catheterization. The performance of Nt-BNP and the PCWP estimate in the detection of HF were studied using receiver operating characteristic (ROC) analysis.


RESULTS
Totally 42 patients had HF. A cardiologist's clinical diagnosis of HF had high specificity (94%) but poor sensitivity (66%). With an optimized cut-off point, plasma Nt-BNP had moderate sensitivity (77%) and specificity (79%) for HF; the ROC area was 0.83. The echocardiographic PCWP estimate classified 90% of patients correctly as having normal or truly elevated (>14 mmHg) PCWP. Its sensitivity and specificity for the diagnosis of HF were 80 and 95% respectively; the ROC area was 0.88. With a cut-off point of 12 mmHg, the sensitivity of the PCWP estimate was 85% and specificity, 88%.


CONCLUSIONS
The recognition of HF in patients with AS can be improved by estimating PCWP using Doppler echocardiography of transmitral and pulmonary venous flow velocities.
Division of Cardiology, Department of Medicine, Helsinki University Central Hospital, Helsinki, Finland. markku.kupari@hus.fi
M
M
Kupari
H
H
Turto
J
J
Lommi
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001024:Aortic Valve Stenosis / Q000150:complications*; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D004452:Echocardiography; D005260:Female; D006333:Heart Failure / Q000175:diagnosis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood
D020097:Natriuretic Peptide, Brain