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Author Namboodiri, Narayanan ♦ Shajeem, O. ♦ Tharakan, Jaganmohan Achuthan ♦ Sankarkumar, R. ♦ Titus, T. ♦ Valaparambil, A. K. ♦ Sivasankaran, S. ♦ Krishnamoorthy, K. M. ♦ Harikrishnan, Sivadasan Pillai ♦ Dora, S. K.
Source Sree Chitra Tirunal Institute for Medical Sciences & Technology
Content type Text
Publisher European Journal of Echocardiography
File Format PDF
Language English
Subject Domain (in DDC) Technology ♦ Medicine & health ♦ Diseases
Subject Domain (in MeSH) Cardiovascular Diseases ♦ Diseases ♦ Diagnosis ♦ Equipment and Supplies ♦ Analytical, Diagnostic and Therapeutic Techniques and Equipment
Subject Keyword Cardiology
Abstract Aims TTK Chitra heart valve prosthesis (CHVP), a tilting disc mechanical heart valve of tow cost and proven efficacy, has been in use for the last 15 years. Although various studies substantiating its long-term safety and efficacy are available, no study had assessed its echocardiographic characteristics. The purpose of this study was to determine the normal Doppler parameters of CHVP in the mitrat position and to assess whether derivation of mitrat valve area (MVA) using the continuity equation (CE) and more commonly used pressure half-time (PHT) method is comparable in the functional assessment of this tilting disc mitral prosthesis.Methods and results Doppler echocardiography was performed in 40 consecutive patients with CHVP in the mitrat position. All patients were clinically stable, without evidence of prosthetic valve dysfunction such as significant obstruction or regurgitation, enclocarditis, left ventricular dysfunction (ejection fraction <40%), or significant aortic regurgitation. Valve sizes studied included 25, 27, and 29 mm. Mitrat valve area was derived both by the PHT method and by the CE, using the stroke volume measured in the ventricular outflow tract divided by the time-velocity integral of CHVP jet. The peak Doppler gradient ranged from 5 to 21 (mean 11.0) mmHg, and the mean gradient ranged from 1.7 to 9.2 (mean 4.1) mmHg. Mean gradient negatively correlated with an increase in the actual orifice area (ACA) derived from the valve orifice diameter given by the manufacturer (r = -0.45, P = 0.004). Mitral valve area calculated by both PHT and CE increased significantly with an increase in the ADA (r = 0.42, P = 0.007 and r = 0.32, P = 0.046, respectively). Mitrat valve area by the CE averaged 1.55 +/- 0.36 cm(2) (range 0.85 cm(2) for a 25 mm valve to 2.41 cm(2) for a 29 mm valve) and was smaller than by PHT (mean 2.04 +/- 0.41 cm(2), range 1.40-3.14 cm(2); P = 0.0001; t-test), irrespective of whether PHT is less than or >110 ms.Conclusion The Doppler parameters obtained with CHVP in the mitrat position are comparable with those obtained with the different prosthetic valves in common use. In the selected group of patients with CHVP, assessment of MVA by the PHT method is comparable with that by the CE. Areas by both methods were smaller than the AOA provided by the manufacturer, as seen in other similar design valves.
Education Level UG and PG
Learning Resource Type Article
Educational Framework Medical Council of India (MCI)
Volume Number 9
Issue Number 5
Page Count 6
Starting Page 599
Ending Page 604