Regurgitant Volume Estimation in Patients with Mitral Regurgitation: Initial Studies Using the Color Doppler “Proximal Isovelocity Surface Area” Method

Abstract

Doppler color flow mapping of a proximal isovelocity surface area (PISA), calculated from a blue-red aliasing radius, has been shown in vitro to be accurate for estimating volume flow rate across a narrowed orifice. Volume flow rate (in cm 3/sec) can be calculated as PISA (in cm 2) x aliasing velocity (in cm/sec). This method has advantages over other color Doppler approaches in that PISA-derived volume flow rate calculations appear to be independent of machine parameter settings and orifice shape. We evaluated the clinical applicability of the PISA method in 49 patients with native valve mitral regurgitation (MR). Color Doppler flow mapping was performed at color aliasing velocities of 54-72 cm/sec. Twenty-four patients were excluded because a color aliasing radius was not clearly seen: 20 of these 24 patients had mild MR. In the remaining 25 patients, the ratio of maximum regurgitant jet area-to-left atrial area, as well as the regurgitant stroke volume estimated using the time-velocity integral method, were compared to regurgitant stroke volume calculated from the PISA method. Maximum PISA was calculated using a formula derived from previous in vitro studies: PISA = 8.05 x r 2, where r is the maximum color Doppler aliasing radius in the apical four-chamber view.(ABSTRACT TRUNCATED AT 250 WORDS)

Impact of TAVI on Mitral Regurgitation: A Prospective Echocardiographic Study

“…These parameters conformed to the recommendations of the European Association of Echocardiography . Structural, Doppler, and quantitative parameters such as the effective regurgitant orifice area (EROA) and MR index were used to grade MR on a scale of 0+ to 4+ with none graded as 0+, mild as 1+, mild‐to‐moderate as 2+, moderate as 3+, and severe as 4+ . To determine the EROA and the MR index, 3 beats were measured and the mean value recorded for patients in sinus rhythm, while at least 5 consecutive beats were recorded in patients with atrial fibrillation.…”

“…9 Structural, Doppler, and quantitative parameters such as the effective regurgitant orifice area (EROA) and MR index were used to grade MR on a scale of 0+ to 4+ with none graded as 0+, mild as 1+, mild-to-moderate as 2+, moderate as 3+, and severe as 4+. 9,10,11 To determine the EROA and the MR index, 3 beats were measured and the mean value recorded for patients in sinus rhythm, while at least 5 consecutive beats were recorded in patients with atrial fibrillation. The EROA measure was then translated into MR grade (according to EAE recommendations for the assessment of valvular regurgitation): EROA >40 mm 2 , severe MR; EROA 30-39 mm 2 , moderate MR; EROA 20-29 mm 2 , mild-to-moderate MR; EROA <20 mm 2 mild MR. 9 The MR index is a simple semiquantitative estimate of MR severity.…”

Transesophageal Echocardiography for the Evaluation of Aorto‐Left Ventricular Tunnel in Adults, with Follow‐ups

“…11 The effective regurgitant orifice area and mitral regurgitation (MR) index were used to grade MR on a scale of absent, trivial or mild, moderate, and severe. [12][13][14] Other echocardiographic parameters considered included the LV ejection fraction (EF) calculated with the Simpson method; left ventricular diameters in diastolic (LVDD). All patients were regularly followed up with TTE and/or TEE during hospitalization and after discharge.…”

Technical problems with diagnostic echocardiography in veterinary medicine

“…This method is used for qualitative evaluation of the severity (mild, moderate, and severe) throughout, not for quantitative evaluation. On the other hand, PISA has been believed to be proportional to regurgitant flow volume regardless of direction of the regurgitant jet [2]. However, it must be kept in mind that a squared element regarding the measurement may become a significant error factor in small-sized hearts; when the display site of measurement in the PISA method measures 4 or 5 mm, the error factor becomes 16 to 25 because the error factor is a squared element.…”