SIGNIFICANCE OF EXERCISE GRADIENTS IN MITRAL STENOSIS: CORRELATION WITH HEMODYNAMICS AND EFFORT INTOLERANCE. Sudhir Wahi*. Agnes Pasquet, Thomas H. Marwick.
Cleveland Clinic Fndtn, Cleveland OH and Univ of Queensland, Brisbane, Australia.
Exercise echo (ExE) provides important prognostic information in patients (pts) with regurgitant valve lesions, but limited data are available regarding its use with mitral stenosis (MS). We sought to assess the factors determining effort tolerance in pts with mild-moderate MS.
Methods: All pts (n-44, M:F-1:6, age 55±13) with mild - moderate mitral stenosis underwent a symptom limited ExE. Based on their response to exercise, pts were grouped into NYHA-1 (n=28), NYHA-II (n=l1) and NYHA-III (n=5). Mitral valve (MV) peak and mean gradients, MV area (MVA) and right ventricle systolic pressure(RVSP) were measured at rest and post exercise.
Results: Correlations between hemodynamic responses and effort tolerance were variable;
|
NYHA |
Class I |
Class II |
Class III |
p |
|
Rest MVA (cm2) |
l.5 |
1.5 |
1.6 |
ns |
|
Rest peak gradient (mmHg) |
14 |
14 |
16 |
ns |
|
Rest mean gradient (mmHg) |
7 |
8 |
9 |
ns |
|
Rest RVSP (mmHg) |
28 |
34 |
58 |
<.01 |
|
Ex Capacity (METS) |
8.0 |
5.8 |
3.4 |
<.01 |
|
Ex Pk gradient (mmHg) |
28 |
27 |
27 |
ns |
|
Ex mean gradient (mmHg) |
15 |
15 |
16 |
ns |
There was no difference in the exercise duration or tolerance in pts with MVA<1.5cm) (n=24) (8.7 minutes and 7 METS) or NWA>I.Scm (n=20) (8.4 minutes and 7 METS)
Conclusion: In pts with mild or moderate MS the presence and severity of pulmonary hypertension is a major determinant of functional capacity. Effort tolerance does not appear to be dependent on the NWA and MV gradients at rest or in response to exercise in this patient group.
