Influence of time in therapeutic range on postoperative complications in mechanical heart valve replacement patients operated with the indigenous TTK Chitra heart valve

Abstract

Objective: Valvular heart disease (VHD) patients after mechanical heart valve (MHV) replacement surgery require postoperative prophylactic anticoagulation to preclude the risk of thromboembolic events. The aim of the present study was to understand the impact of international normalised ratio (INR) variability and time in therapeutic range (TTR) in balancing the choice of antithrombotic therapy and its outcomes in patients who underwent the MHV replacement. Methods: This retrospective cohort study was conducted between January 2018 to December 2019 at a tertiary care hospital in South India. Results: A total of 159 patients with a mean age of 37.31 (12) years were operated for MHV replacement. Of 159 patients, 50 patients (31.4%) were male and 109 (68.6%) were female. From the cohort, majority of the patients underwent mitral valve replacement (93, 58.5%), followed by double valve replacement (34, 21.4%) and aortic valve replacement (32, 20.1%). Post-surgery, 36 patients had thromboembolic complications, where the majority suffered from peripheral embolism (18, 50%), followed by ischemic stroke (10, 27.7%), and prosthetic valve thrombosis (8, 22.2%). The most common post-operative anti-coagulation drug used was warfarin (124, 79%). The INR range of 2.01 – 2.49 (p - 0.003) was reported to be significant for mitral valve and double valve replacement patients. Conclusion: Overall, the complication rates in the Indian population who underwent MHV replacement was reported to be low. To conclude, higher the TTR - lesser will be the risk of developing complications and vice versa.

Keywords

• valvular heart disease
• mechanical heart valve replacement
• international normalised ratio
• time in therapeutic range
• postoperative complications
• ttk chitra valve