Assessment of cardiac remodeling in asymptomatic mitral regurgitation for surgery timing: a comparative study of echocardiography and magnetic resonance imaging.
BACKGROUND
Early surgery is recommended for asymptomatic severe mitral regurgitation (MR), because of increased postoperative left ventricular (LV) dysfunction in patients with late surgery. On the other hand, recent reports emphasized a "watchful waiting" process for the determination of the proper time of mitral valve surgery. In our study, we compared magnetic resonance imaging (MRI) and transthoracic echocardiography to evaluate the LV and left atrial (LA) remodeling; for better definitions of patients that may benefit from early valve surgery.


METHODS
Twenty-one patients with moderate to severe asymptomatic MR were evaluated by echocardiography and MRI. LA and LV ejection fractions (EFs) were calculated by echocardiography and MRI. Pulmonary veins (PVs) were measured from vein orifices in diastole and systole from the tangential of an imaginary circle that completed LA wall. Right upper PV indices were calculated with the formula; (Right upper PV diastolic diameter- Right upper PV systolic diameter)/Right upper PV diastolic diameter.


RESULTS
In 9 patients there were mismatches between echocardiography and MRI measurements of LV EF. LV EFs were calculated > or = 60% by echocardiography, meanwhile < 60% by MRI in these 9 patients. Severity of MR evaluated by effective regurgitant orifice area (EROA) didn't differ with preserved and depressed EFs by MRI (p > 0.05). However, both right upper PV indices (0.16 +/- 0.06 vs. 0.24 +/- 0.08, p: 0.024) and LA EFs (0.19 +/- 0.09 vs. 0.33 +/- 0.14, p: 0.025) were significantly decreased in patients with depressed EFs when compared to patients with normal EFs.


CONCLUSIONS
MRI might be preferred when small changes in functional parameters like LV EF, LA EF, and PV index are of clinical importance to disease management like asymptomatic MR patients that we follow up for appropriate surgery timing.
Ozdogan
Oner
O
Tepecik Training and Research Hospital, Cardiology Department, Izmir, Turkey. onerozdogan@yahoo.com
Yuksel
Alper
A
Gurgun
Cemil
C
Kayikcioglu
Meral
M
Yavuzgil
Oguz
O
Cinar
Cahide S
CS
D000328:Adult; D006348:Cardiac Surgical Procedures; D003937:Diagnosis, Differential; D015150:Echocardiography, Doppler / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008944:Mitral Valve Insufficiency / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery; D011300:Preoperative Care / Q000379:methods*; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D013318:Stroke Volume; D013997:Time Factors; D016277:Ventricular Function, Left / Q000502:physiology*; D020257:Ventricular Remodeling / Q000502:physiology*