[Transthoracic and transesophageal echo Doppler in the detection of mitral prosthesis dysfunction due to...

Severe mitral regurgitation is accompanied by increment of left atrial pressure. The objective of this work was to compare Doppler parameters related to transvalvular peak-pressure gradient in patients with normally functioning and patients with malfunctioning mitral prosthetic valve, secondary to insufficiency, in order to analyze if the presence of high protodiastolic pressure gradient and normal prosthetic valve area could correlate with severe mitral regurgitation (MR). Fourty-two patients were studied. Group I: twenty-two normally functioning prosthesis (15 mechanical, 7 biological). Group II: twenty malfunctioning mitral prosthetic valves secondary to severe insufficiency (11 mechanical and 9 biological), 12 patients with acute MR and 8 with chronic MR. All of the patients were evaluated though transthoracic (TTE) and transesophageal (TEE) Doppler-echocardiography. Diastolic peak velocity prosthetic flow (DVP), protodiastolic gradient (PDG), mean gradient (MG) and prosthetic area (PA) by pressure halftime (PHT) were measured. DVP in Group I was 1.56 +/- 0.29 m/s and 2.49 +/- 0.30 m/s in Group II (p = 0.001). PGD measured 10.36 +/- 3.79 mmHg in Group I and 15.95 +/- 7.48 mmHg in Group II (p = 0.001). MG 4.86 +/- 1.90 mmHg in Group I and 10.38 +/- 4.8 mmHg in Group II (p = 0.001). PA was 2.01 +/- 0.54 cm2 in Group I and 2.10 +/- 0.43 cm2 in Group II (NS). PHT was 115.59 +/- 31.99 mseg in Group I and 108.3 +/- 19.1 mseg in Group II (NS).

In patients with high PDG (greater than 20 mmHg) and normal prosthetic mitral area assessed by TTE could be suspicious of malfunctioning prosthesis secondary to severe insufficiency. Due to the higher sensitivity and specificity in the diagnosis of malfunctioning mitral prosthesis and the ability to determine the magnitude and severity of prosthetic regurgitation assessment should be completed with TTE.