Читать книгу Practical Cardiovascular Medicine - Elias B. Hanna - Страница 129

1 Transthoracic echo (TTE) is the initial test. TTE shows a left-to-right shunt in VSR. It may miss severe acute MR because of the narrowing of the pressure difference between the LV and the LA, leading to attenuation of the regurgitant color flow. TTE may show a pericardial effusion with layered echodensities, corresponding to blood, in free wall rupture; however, it may miss a sealed rupture (an effusion is not seen in 25% of sealed ruptures).¹²⁵

2 If the severity/mechanism of MR is unclear on TTE in a patient with shock, perform transesophageal echocardiography.

3 MRI is needed when a sealed free wall rupture is suspected but not well delineated by echo.

4 Right heart catheterization may also be useful to diagnose VSR and MR:In VSR, there is O2 saturation step-up ≥7% between RA and RV.In MR, PCWP tracing has a giant V wave; however, a large V wave is also seen with VSR or severe LV failure. In both MR and VSR,PCWP is higher than LVEDP.

5 Left ventriculography may be performed during PCI in a patient with cardiogenic shock. It allows the diagnosis of severe MR, VSR, or free wall rupture.