RESUMO
Left atrial spontaneous echo contrast [SEC] is a marker of blood stagnation in the left atrium in mitral valve disease and a forerunner of cardiogenic thromboembolism. To assess the effect of mitral balloon valvuloplasty on SEC visualization in the left atrium [LA] in rheumatic mitral valve disease, 30 patients with rheumatic mitral stenosis [MS] [7 males and 23 females, mean age 30 +/- 10.5 years] were studied by transthoracic echocardiography [TTE] including M-mode, two-dimensional, continuous and pulsed wave Doppler with colour flow mapping for the detection of associated or consequent mitral regurgitation [MR]; as well as transoesophageal echocardiography [TEE] prior to and within one week after balloon valvuloplasty [BV] of the mitral valve. Measurements of LA dimensions, mitral valve area [MVA], mitral valve score [MVS], mean transvalvular pressure gradient [MPG] and fractional shortening [FS] were carried out. TEE was utilized to detect SEC in the LA and determine its grade, as well as to rule out the likelihood of thrombus formation in the LA or left atrial appendage [LAA] and to measure the thickness of the interatrial septum [IAS]. TTE failed to detect SEC in all patients and proved insensitive in this respect. The impact of BV was manifested by a significant reduction of the LA diameter, a significant increase in FS, a significant increase in the 2-D estimated MVA and in the Doppler-estimated MVA and a reduction of MPG. Before BV, only 9 patients [30%] depicted an evidence of associated grade I MR, whereas after BV 21 patients depicted MR of grade 1[80.9%] and grade 11[19.1%], while the remaining 9 patients [30%] revealed no trace of MR. Before BV, a SEC was displayed in all patients [100%], 13 [43.3%] having +1 SEC. 8 patients [26.7%] having +2 SEC and 9 patients [30%] having +3 SEC; whereas after BV, only 9 patients [30%] had SEC. 6 among them [66.7%] depicting +1 SEC and 3 [33.3%] depicting +2 SEC. Thus, 21 patients [70%] were free of SEC post-BV. Before BV, the grade of SEC was a function of cardiac rhythm [the majority of patients with atrial fibrillation "AF" displayed +3 SEC vs. +1 and +2 SEC in those with sinus rhythm], mean transmitral pressure gradient [the higher the MPG the higher the grade of SEC] and fractional shortening [the lower the FS the higher the grade of SEC. p=0.03]. The rate of resolution of SEC post-BV was a function of age, fractional shortening, MPG across the mitral valve, cardiac rhythm [SEC was more common in association with AF than with sinus rhythm] and mitral regurgitation [SEC was more common in patients with MR]; whereas gender and LA diameter exhibited no striking influence on the rate of resolution of SEC post-BV. It was concluded that TEE is greatly superior to TTE in detecting SEC in patients with rheumatic MS pre- and post-BV, that the frequency of SEC detection is related to cardiac dysrhythmia, particularly chronic AF, MPG across the mitral valve, FS and age of the patient. Successful BV is associated with a significant resolution in SEC or reduction in its grade due to the establishment of a wider MVA, hence a lower MPG, better ventricular filling and higher FS. The visualization of SEC should be considered as a prothrombotic state warranting anticoagulation