Invasive evaluation of mitral regurgitation: the importance of hemodynamic measurements during exercise

In patients with mitral regurgitation, left ventricular angiography is usually performed to grade the regurgitation. This is a semi-quantitative method which gives some information related to the regurgitant volume at a certain time. The aim of our study was to evaluate the benefits of invasive hemodynamic examinations during stress. Patients with mitral regurgitation according to Doppler color flow mapping, and regurgitation of no more than grade 2+ according to left ventricular angiography, were of special interest.

One hundred and four consecutive patients were examined with transesophageal echocardiography (TEE), left ventricular angiography and cardiac catheterization during rest and during hemodynamic stress.

All patients had mitral regurgitation according to Doppler color flow mapping. Thirty eight patients had a mitral regurgitation of grade 0, 1+ or 2+ according to left ventricular angiography. Of these, seven had a resting v-wave < or = 25 mmHg, and a v wave > or = 50 mmHg during stress. When these seven patients were compared with those with severe grade 3+ and 4+ regurgitation, there was a significant difference between the v-wave at rest (p = 0.02) but no significant difference during stress (p = 0.42).

Mitral regurgitation is a dynamic lesion, the complete assessment of which cannot be obtained from a single measure during one hemodynamic situation. Additional information from v-wave recordings during hemodynamic stress identified a subgroup of patients who had near-normal pressures at rest, but whose v-wave measurements during stress did not differ significantly from those of patients with severe angiographically assessed regurgitation (grades 3+ and 4+). In patients with only minor mitral regurgitation which is suspected to contribute to their clinical symptoms, the monitoring of invasive hemodynamic parameters during stress is important.