Doppler Echocardiography of 79 Normal CarboMedics Mitral Prostheses: A Comprehensive Assessment Including Time-Velocity Integral Ratio and Prosthesis Performance Index

doi:10.1016/j.echo.2007.02.027

Journal of the American Society of Echocardiography

Volume 20, Issue 10, October 2007, Pages 1125-1130

https://doi.org/10.1016/j.echo.2007.02.027 Get rights and content

Few reports have been published on the normal Doppler-derived echocardiographic data for CarboMedics (CarboMedics Inc., Austin, TX) prosthesis function in the mitral position. The purpose of this study was to provide a comprehensive Doppler echocardiographic assessment of normal CarboMedics mitral prosthesis function in a large number of patients. All of the important Doppler-derived hemodynamic variables reported to date were used. The pressure half-time was less than 130 msec in all patients, and nearly all patients (95%) had either a peak early mitral diastolic velocity of 2 m/s or less or a mitral valve prosthesis-to-left ventricular outflow tract time-velocity integral ratio of less than 2.2, regardless of prosthesis size or left ventricular function. No significant differences were found among different prosthesis sizes for effective orifice area, effective orifice area indexed to body surface area, or prosthesis performance index.

Section snippets

Patient Selection

From the cardiac surgical database at Mayo Clinic in Rochester, Minnesota, 81 patients aged 18 years or older were identified who underwent isolated mitral valve replacement with a CM prosthesis between 1993 and 2003 and who had a two-dimensional (2D) and Doppler echocardiographic study within 4 weeks after surgery. Included in the 81 patients were 13 with corrected transposition who had replacement of the left-sided, morphologic tricuspid valve, which is equivalent (from a hemodynamic

Baseline Clinical Characteristics

Patient characteristics are listed in Table 1. A standard bileaflet CM prosthesis was implanted in all patients. The indications for mitral valve replacement were mitral regurgitation in 47 patients (59%), mitral stenosis in 15 patients (19%), and mixed stenosis and regurgitation in 17 patients (22%). Seventy patients (89%) had TTE performed within the first week after mitral valve replacement. Results of physical examination and the appearance of the prosthesis by intraoperative

Discussion

In the present study of normal CM prostheses in the mitral position, all but three patients (4%) had either an E velocity that did not exceed 2 m/s or a TVI_MVP/TVI_LVOT ratio less than 2.2, regardless of prosthesis size or left ventricular systolic function. PHT was less than 130 msec in all patients in whom it could be measured. The combination of an E velocity less than 1.9 m/s, a TVI_MVP/TVI_LVOT ratio less than 2.2, and a PHT less than 130 msec was observed in 67% of our patients with complete

Conclusion

Ascertaining normal cardiac prosthetic valve function remains a challenge. The intent of this study was to provide in vivo data on a large number of normal CM mitral prostheses including all of the important Doppler variables described to date. The findings can be used for comparison when assessing patients with CM mitral prostheses. Outlier Doppler data should prompt further evaluation, including TEE, for possible prosthesis dysfunction.

Acknowledgment

Editing, proofreading, and reference verification were provided by the Section of Scientific Publications, Mayo Clinic.

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Doppler echocardiography of 119 normal-functioning St Jude Medical mitral valve prostheses: a comprehensive assessment including time-velocity integral ratio and prosthesis performance index
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Cited by (13)

Doppler Parameters Derived from Transthoracic Echocardiography Accurately Detect Bioprosthetic Mitral Valve Dysfunction
2017, Journal of the American Society of Echocardiography
Detecting bioprosthetic mitral valve dysfunction on transthoracic echocardiography can be challenging because of acoustic shadowing of regurgitant jets and a wide normal range of transvalvular gradients. Several studies in mechanical mitral valves have demonstrated the utility of the transthoracically derived parameters E (peak early mitral inflow velocity), pressure half-time, and the ratio of mitral inflow velocity-time integral (VTI_MV) to left ventricular outflow tract velocity-time integral (VTI_LVOT) in detecting significant prosthetic dysfunction. Uncertainty exists as to their applicability and appropriate cutoff levels in bioprosthetic valves. This study was designed to establish the accuracy and appropriate normal limits of routinely collected transthoracic Doppler parameters when used to assess bioprosthetic mitral valve function.
A total of 135 clinically stable patients with bioprosthetic mitral valves who had undergone both transthoracic and transesophageal echocardiography within a 6-month period were retrospectively identified from the past 11 years of the echocardiography database. Transthoracic findings were labeled as normal (n = 81), regurgitant (n = 44), or stenotic (n = 10) according to the patient's transesophageal echocardiographic findings. Univariate and multivariate analyses were performed to identify Doppler parameters that detected dysfunction; then receiver operating characteristic curves were created to establish appropriate normal cutoff levels.
The VTI_MV/VTI_LVOT ratio was the most accurate Doppler parameter at detecting valvular dysfunction, with a ratio of >2.5 providing sensitivity of 100% and specificity of 95%. E > 1.9 m/sec was slightly less accurate (93% sensitivity, 72% specificity), while a pressure half-time of >170 msec had both 100% specificity and sensitivity for detecting significant bioprosthetic mitral valve stenosis, (although it did not differentiate between regurgitant and normal).
This study demonstrates that Doppler parameters derived from transthoracic echocardiography can accurately detect bioprosthetic mitral valve dysfunction. These parameters, particularly a VTI_MV/VTI_LVOT ratio of >2.5, are a sensitive way of selecting patients to undergo more invasive examination with transesophageal echocardiography.
Echocardiographic Assessment of Prosthetic Heart Valves
2014, Progress in Cardiovascular Diseases
Citation Excerpt :
E velocity and TVI ratio cut-off values predictive of bioprosthetic mitral valve regurgitation have not yet been validated. On the basis of a series from our institution, we propose that pathologic regurgitation is present when PHT < 120 ms and TVI ratio ≥ 2.6, ≥ 2.8 and ≥ 3.9 for mitral bileaflet mechanical, pericardial and porcine prostheses, respectively.5,6,14–16 If regurgitant jets are able to be adequately visualized, transprosthetic and periprosthetic mitral valve regurgitation can be semi-quantitated using the same methods that have been elucidated for native mitral valve regurgitation13 (Table 4).
Valvular heart disease is a global health problem. It is estimated that more than 280,000 prosthetic heart valves are implanted worldwide each year. As the world's population is aging, the incidence of prosthetic heart valve implantation and the prevalence of prosthetic heart valves continue to increase. Assessing heart valve prosthesis function remains challenging, as prosthesis malfunction is unpredictable but not uncommon.
Transthoracic two-dimensional and Doppler echocardiography is the preferred method for assessing prosthetic valve function. Clinically useful Doppler-derived measures for assessing prosthetic valve hemodynamic profiles have been reported for aortic, mitral, and tricuspid valve prostheses, but echocardiographic data regarding pulmonary valve prostheses remain limited. Complete prosthetic valve evaluation by transthoracic echocardiography (TTE) is sometimes challenging due to acoustic shadowing and artifacts. In these cases, further imaging with transesophageal echocardiography, fluoroscopy and/or gated CT may be warranted, particularly if prosthetic valve dysfunction is suspected. Being able to differentiate pathologic versus functional obstruction of an individual prosthesis is extremely important, as this distinction affects management decisions. Transprosthetic and periprosthetic regurgitation may be difficult to visualize on TTE, so careful review of Doppler-derived data combined with a high index of suspicion is warranted, particularly in symptomatic patients. A baseline TTE soon after valve implantation is indicated in order to “fingerprint” the prosthesis hemodynamic profile. It remains unclear how frequently serial imaging should be performed in order to assess prosthetic valve function, as this issue has not been systematically studied.
Comprehensive hemodynamic assessment of 368 normal St. Jude Medical mechanical mitral valve prostheses based on early postimplantation echocardiographic studies
2013, Journal of the American Society of Echocardiography
Two-dimensional and Doppler-derived echocardiographic data on normal St. Jude Medical mechanical mitral valve prosthesis function have been reported but remain limited.
Comprehensive retrospective two-dimensional and Doppler echocardiographic assessment of 368 normal St. Jude Medical mechanical mitral valve prostheses was performed early after implantation. The early postimplantation hemodynamic profiles of 98 patients were compared with profiles obtained by follow-up transthoracic echocardiography performed <13 months after implantation.
Using mean ± 2 SDs to define the normal distribution of values for Doppler-derived hemodynamic variables, the calculated normal ranges of values were as follows: mean gradient, 2 to 7 mm Hg; peak early mitral diastolic velocity (E velocity), 1.1 to 2.4 m/sec; time-velocity integral of the mitral valve prosthesis (TVI_MVP) 20 to 50 cm; ratio of the TVI_MVP to the time-velocity integral of the left ventricular outflow tract (TVI_LVOT), 0.9 to 2.5; pressure half-time, 35 to 99 msec; and effective orifice area, 1.12 to 3.24 cm². Patients with severe prosthesis-patient mismatch (ie, indexed effective orifice area ≤ 0.9 cm²/m²) had significantly higher mean gradients, E velocity, TVI_MVP, and TVI_MVP/TVI_LVOT. There was a trend for longer pressure half-times for patients with severe prosthesis-patient mismatch than for patients without severe prosthesis-patient mismatch, but none of these patients had pressure half-times > 130 msec. Among the 98 patients with follow-up transthoracic echocardiography <1 year after implantation, no significant differences were observed between early postimplantation findings and follow-up hemodynamic profiles.
This study establishes parameters (mean ± 2 SDs) defining the distribution of values for Doppler-derived hemodynamic data with normal St. Jude Medical mechanical mitral valve prostheses. Prostheses with hemodynamic values outside these parameters are likely dysfunctional; however, prosthesis dysfunction may be present even when hemodynamic values are within these ranges.
Comprehensive hemodynamic assessment of 305 normal carbomedics mitral valve prostheses based on early postimplantation echocardiographic studies
2012, Journal of the American Society of Echocardiography
Citation Excerpt :
The recent ASE and EAE guidelines use the cutoff values determined by Fernandes et al.2 to define normal prosthetic mitral valve function. We used similar cutoff values when evaluating the 79 normal CM mechanical mitral valve prostheses included in our previous study6 and found that although 65 of the 70 patients (93%) for whom complete hemodynamic data were available had either E velocities < 1.9 m/sec or TVI ratios < 2.2; only 59 (84%) had E velocities < 1.9 m/sec, TVI ratios < 2.2, and PHTs < 130 msec. In the present study, only 160 of the 288 patients (56%) in whom PHT could be measured met these criteria.
Two-dimensional (2D) and Doppler-derived echocardiographic data on normal CarboMedics (CM) mechanical mitral valve prosthesis function have been reported but are limited.
Comprehensive retrospective 2D and Doppler echocardiographic assessment of 305 normal CM mechanical mitral valve prostheses (272 Standard and 33 Optiform) was performed early after implantation. The early postimplantation hemodynamic profiles of 80 patients were compared with profiles obtained by follow-up transthoracic echocardiography performed <1 year after implantation.
CM Standard and Optiform prostheses had similar hemodynamic profiles. With mean ± 2 SDs used to define the normal distribution of values for hemodynamic variables, the calculated normal range of values was as follows: mean gradient, 2 to 7 mm Hg; peak early mitral diastolic velocity, 1.3 to 2.4 m/sec; time-velocity integral (TVI) of the mitral valve prosthesis (TVI_MVP), 20 to 50 cm; ratio of TVI_MVP to the TVI of the left ventricular outflow tract, 0.9 to 2.5; pressure half-time, 35 to 99 msec; and effective orifice area, 1.17 to 3.25 cm². Patients with severe prosthesis-patient mismatch (indexed effective orifice area ≤ 0.9 cm²/m²) had significantly higher mean gradients, peak early mitral diastolic velocities, TVI_MVP, ratios of TVI_MVP to the TVI of the left ventricular outflow tract, and pressure half-time values than values without severe prosthesis-patient mismatch, but none had pressure half-time values > 120 msec. Among the 80 patients with follow-up transthoracic echocardiography within 1 year after implantation, no significant differences were noted between early postimplantation findings and follow-up hemodynamic profiles.
This study establishes parameters (mean ± 2 SD) defining the distribution of findings for Doppler-derived hemodynamic data with normal CM mechanical mitral valve prostheses. Prostheses with hemodynamic values outside these parameters are likely dysfunctional; however, prosthesis dysfunction may be present even when hemodynamic values are within these ranges.
Comprehensive echocardiographic assessment of mechanical tricuspid valve prostheses based on early post-implantation echocardiographic studies
2011, Journal of the American Society of Echocardiography
Doppler-derived hemodynamic data for normal tricuspid mechanical valve prostheses are limited.
A comprehensive retrospective Doppler echocardiographic assessment of 78 normal St. Jude Medical Standard (St. Jude Medical, Inc., St. Paul, MN), CarboMedics Standard (CarboMedics, Inc., Sorin Group, Burnaby, British Columbia, Canada), and Starr-Edwards (Edwards Lifesciences, LLC, Irvine, CA) mechanical tricuspid valve prostheses was performed early after implantation. We used all the important Doppler-derived hemodynamic variables reported to date, including peak early diastolic velocity (E velocity), mean gradient, pressure half-time, time velocity integral of the tricuspid valve prosthesis (TVI_TVP), and ratio of the time velocity integral of the tricuspid valve prosthesis to the time velocity integral of the left ventricular outflow tract (TVI_TVP/TVI_LVOT).
The mean values obtained for the Doppler parameters did not differ significantly when the measurements from five or nine consecutive cardiac cycles were averaged. Pressure half-time was <130 msec in all 43 patients with St. Jude Medical Standard and CardioMedics Standard prostheses in whom it could be measured. Mean gradient <6 mm Hg, E velocity <1.9 m/s, TVI_TVP <46 cm, and TVI_TVP/TVI_LVOT <2.1 were recorded in 59 (87%) of the 68 patients with either of these prostheses. Hemodynamic variables were considerably less favorable in patients with Starr-Edwards prostheses.
These calculated threshold values (mean + 2 SD) are useful for identifying normal tricuspid mechanical valve function. Prostheses with values for hemodynamic variables that are outside the mean + 2 SD parameters that we have calculated are most likely to be dysfunctional. However, in rare cases, mechanical tricuspid valve prostheses may be dysfunctional even when their hemodynamic parameters are within these specified ranges because of small body surface area or other factors.
Comprehensive echocardiographic assessment of the hemodynamic parameters of 285 tricuspid valve bioprostheses early after implantation
2010, Journal of the American Society of Echocardiography
Citation Excerpt :
With significant mitral prosthetic and/or periprosthetic regurgitation, increased MG and TVIMVP are accompanied by normal to reduced stroke volume through the left ventricular outflow tract, resulting in an increased TVIMVP/TVILVOT. Nearly all patients with normal functioning bileaflet mechanical mitral valve prostheses have TVIMVP/TVILVOT < 2.2, and the combination of E velocity < 1.9 m/sec, TVIMVP/TVILVOT < 2.2, and PHT < 130 msec has been found to be highly predictive of normal mechanical mitral valve prosthesis function.3,9–11 On the other hand, the combination of E velocity ≥ 1.9 m/sec, TVIMVP/TVILVOT ≥ 2.2, and PHT < 130 msec suggests significant prosthetic and/or periprosthetic regurgitation for mechanical mitral valve prostheses.
Doppler-derived hemodynamic data for normal tricuspid valve bioprostheses are limited.
A comprehensive retrospective Doppler echocardiographic assessment of 285 normal Carpentier-Edwards Duraflex, Medtronic Mosaic, St. Jude Medical Biocor, Carpentier-Edwards Perimount, and Medtronic Hancock II tricuspid valve bioprostheses was performed early after implantation. All the important Doppler-derived hemodynamic variables reported to date for mitral valve prostheses were used. Mean values for hemodynamic variables were obtained by averaging measurements of five and nine consecutive cardiac cycles.
No clinically significant difference was found in the mean values obtained for the Doppler parameters when measurements were averaged from five or nine consecutive cardiac cycles. The mean value for the mean gradient was 5.2 mm Hg. Regardless of valve type and body surface area, pressure half-time was <200 msec for all 76 patients in whom it could be measured. Mean gradient <9 mm Hg, E velocity <2.1 m/sec, time-velocity integral of the tricuspid valve prosthesis <66 cm, and ratio of the time-velocity integral of the tricuspid valve prosthesis to the time-velocity integral of the left ventricular outflow tract <3.3 were recorded in 254 of the 285 patients (89%).
This study establishes parameters for Doppler-derived hemodynamic data for various types of normal tricuspid valve bioprostheses. These threshold values (mean + 2 standard deviations) are specific, but not sensitive, for identifying tricuspid valve bioprosthesis dysfunction. Prostheses with hemodynamic values that are higher than these threshold values are likely dysfunctional, but in select cases, tricuspid valve bioprosthesis dysfunction may be present even when hemodynamic values are lower than these thresholds.

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Original articleDoppler Echocardiography of 79 Normal CarboMedics Mitral Prostheses: A Comprehensive Assessment Including Time-Velocity Integral Ratio and Prosthesis Performance Index

Section snippets

Patient Selection

Baseline Clinical Characteristics

Discussion

Conclusion

Acknowledgment

Am J Cardiol

J Am Soc Echocardiogr

J Am Soc Echocardiogr

J Am Coll Cardiol

J Am Soc Echocardiogr

Original article
Doppler Echocardiography of 79 Normal CarboMedics Mitral Prostheses: A Comprehensive Assessment Including Time-Velocity Integral Ratio and Prosthesis Performance Index