Pitfalls in Quantifying the Severity of Mitral Valve Regurgitation
A 56-year-old man was referred for evaluation of severity of mitral regurgitation (MR). Three years ago, he was diagnosed with moderate mitral valve regurgitation due to mitral valve prolapse during a regular follow-up for his stable coronary artery disease. During his last visit with the referring cardiologist, the MR appeared to have increased. At that time, the patient did not report any symptoms and claimed to regularly perform mountain hikes. A bicycle stress test was terminated because of dyspnea at 98% of the age/gender predicted work capacity. Stress echocardiography immediately after the stress test revealed a right ventricle to right atrium pressure gradient of 69 mmHg.
On examination, the patient did not show clinical signs of cardiopulmonary decompensation. His blood pressure was 128/72 mmHg, and his resting heart rate was 56 bpm. On auscultation, there was a 3/6 systolic murmur at the apex and the left parasternal border.
Transthoracic echocardiography revealed eccentric MR toward the aortic root (Movie 1). The left ventricular (LV) size and systolic function were within normal range (LV volume indexed to body size: 56 ml/m2, three-dimensional [3D] LV ejection fraction: 61%), and the left atrium size was in the upper normal range (34 ml/m2 by 3D echocardiography). However, 3D strain depicted a reduced LV global longitudinal strain of -16.6% (normal range -19.9 ± 3.1) (Movie 2). Detailed analyses of the MR are shown in Movies 3 and 4, including systolic reversal of pulmonary vein flow, quantification of MR, and 3D transesophageal echocardiography (TEE).
A coronary angiogram showed patent epicardial coronary arteries. The results of the right heart catheter were as follows:
- Cardiac index = 1.7 l/min/m2
- LV end diastolic pressure = 12 mmHg
- Mean wedge pressure = 15 mmHg
- V-wave = 18 mmHg
- Mean pulmonary pressure = 17 mmHg
The kidney function and the level of N-terminal pro-B-type natriuretic peptide were normal.
Should this patient be referred for mitral valve surgery?