Hemodynamic performance evaluation of TTK Chitra heart valve prosthesis in the aortic position using Doppler echocardiography

Long-term evaluation of TTK Chitra™ heart valve prosthesis - a retrospective-prospective cohort study

Purpose

The TTK Chitra™ heart valve has more than 1,40,000 implantations so far, but no long-term data has been published. This study aims to provide long-term results of the valve.

Methodology

A cohort of 476 patients with implantations from January 2006 to December 2018 were followed up prospectively consisting of 104 aortic valve replacement (AVR), 87 double valve replacement (DVR), and 285 mitral valve replacement (MVR) patients. Total follow-up was 4079 patient-years (py) (AVR = 983, MVR = 2392, DVR = 704), being 96% complete.

Results

The results showed that actuarial survival at 15 years was 82.3% for AVR, 60.7% for MVR, and 52.2% for DVR. Freedom from all valve-related mortality and morbidity at 15 years was 73.8%, 64.8%, and 61.9% for AVR, MVR, and DVR, respectively. There was one instance of structural failure of valve disc leading to severe valvar regurgitation. Valve thrombosis incidence was 1 in AVR (0.1%/py), 6 in MVR (0.25%/py), and 1 in DVR (0.14%/py). Thrombo-embolic episodes occurred in 50 patients (AVR = 7 patients at 0.7%/py; MVR = 36 patients at 1.5%/py; DVR = 7 patients at 0.99%/py) and major hemorrhage (bleeding) in 24 patients (AVR = 0.61%/py; MVR = 0.5%/py; and DVR = 0.85%/py). The linearized rates of adverse events in this study were found to be lower than earlier published results.

Conclusion

The results highlight the continued safety and performance of the TTK Chitra™ heart valve (TTKCHV) in the long term at 15 years.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12055-022-01437-9.

Clinical outcomes of bileaflet St. Jude Medical and tilting disc TTK Chitra mechanical heart valve prosthesis: A comparative study

BACKGROUND

Comparative data on the clinical outcomes of TTK Chitra mechanical heart valve prosthesis (CHVP), an indigenously developed low-cost tilting disc valve and commonly used bileaflet valve, the St. Jude medical (SJM) prosthesis are sparse.

METHODS

We conducted a retrospective follow-up study of consecutive patients undergoing mitral (MVR) and aortic valve replacement (AVR) with SJM or CHVP mechanical prostheses over a 6-year period at our institution.

RESULTS

Seven hundred and thirty-five patients who underwent isolated MVR (n = 510) or AVR (n = 225) were included in the study. Patients with CHVP were younger and belonged to a lower socioeconomic class. The study cohort was followed-up for 2836 patient-years (SJM: 1865.1, CHVP: 971.0). All-cause mortality (p = 0.894), valve-related mortality (p = 0.681), prosthetic valve thrombosis (p = 0.155), embolism (p = 0.210), hemorrhage (p = 0.959) and infective endocarditis (IE, p = 0.084) were similar between both valve on follow-up. Estimated event free survival was 2302 ± 1 days in SJM as compared to 2484 ± 65 days in CHVP group (p = 0.393). Valve type was not an independent predictor of adverse events after adjusting for baseline data, time in therapeutic range and aspirin use. Subgroup analysis of patients who underwent MVR and AVR showed similar functional improvement and outcomes, except for a higher incidence of IE with SJM at the aortic position (p = 0.041).

CONCLUSION

The indigenously developed, low-cost CHVP has comparable midterm clinical performance as SJM in aortic or mitral positions.

Intraoperative Transesophageal and Postoperative Transthoracic Echocardiographic Evaluation of a Mechanical Heart Valve Prosthesis Implanted at Aortic Position

OBJECTIVE

The aims of this study were to evaluate the intraoperative transesophageal echocardiographic (iTEE) characteristics and Doppler flow profile of aortic Chitra heart valve prosthesis (CHVP) under stable hemodynamic and loading conditions, and to compare and correlate the iTEE data with the postoperative transthoracic echocardiography (TTE) data obtained at 48 hours (TTE₁) and 3 months (TTE₂) after the surgery.

DESIGN

Prospective, observational study.

SETTING

University-level tertiary referral hospital.

PARTICIPANTS

Forty patients between 18 years and 65 years of age undergoing elective aortic valve replacement (AVR) using CHVP during the period January 2015 to August 2016.

INTERVENTIONS

After obtaining permission from institutional ethics committee, 40 patients undergoing elective AVR were studied prospectively. The iTEE examination was performed in the pre-cardiopulmonary bypass (CPB) and post-CPB period in all the study subjects. CHVP was subjected to iTEE two-dimensional (2D) echo, color Doppler, and spectral Doppler evaluation under stable hemodynamic and loading condition in the post-CPB period after the administration of protamine. The CHVP were re-evaluated using TTE in all the patients 48 hours after the surgery (TTE₁) and 3 months after the surgery (TTE₂). The iTEE and postoperative TTE Doppler values were compared and correlated.

MEASUREMENTS AND MAIN RESULTS

The CHVP could be imaged adequately and interrogated with Doppler in all the patients. None of the patients had restriction of occluder mobility or unstable seating of the valve. The intraoperative flow dependent (peak velocity [PV] and mean pressure gradient [MPG]) and less flow dependent (Doppler velocity index, acceleration time, acceleration time/ejection time, effective orifice area [EOA] and indexed EOA) Doppler parameters of CHVP were measured as per the American Society of Echocardiography recommendations. The PV and MPG of CHVP measured by iTEE showed no statistical difference (p > 0.05) and were in limits of agreement when compared with TTE₁ and TTE₂ data.

CONCLUSION

The iTEE features of CHVP were found compliant with the criteria set by the ASE defining normal functioning of an aortic valve prosthesis. The iTEE Doppler parameters obtained under stable loading conditions strongly predicted the postoperative values of Doppler parameters on TTE examination. The iTEE Doppler values can be used as the reference values for the postoperative follow up studies.