Evaluation of anticoagulation in post-surgical patients with mechanical valve replacement


  • Sana Sehar Cardiology Department PIC
  • Hurmah Shoaib Punjab Institute of Cardiology, Lahore
  • Mahrukh Mansoor Khosa Punjab Institute of Cardiology, Lahore
  • Syed Ali Hamza Punjab Institute of Cardiology, Lahore
  • Fizza Mobasher Punjab Institute of Cardiology, Lahore
  • Ali Nasir Punjab Institute of Cardiology, Lahore




Valvular Heart Disease, International Normalized Ratio, Mechanical Valve Replacement.


BACKGROUND: Mitral, aortic, tricuspid, and pulmonary valve disease are the four types of valvular heart disease. Valvular heart disease is defined by damage to or a congenital abnormality in one or more of the heart's valves. Rheumatic heart disease is the term used to describe valvular heart disease that develops as a consequence of rheumatic fever. There have been several suggestions made regarding biomarkers that might be used for tracking the aetiology of aortic valve disease; however, not all biomarkers are candidates that are clinically helpful. Patients who are taking vitamin K antagonists are typically advised to have their blood tested using the international normalised ratio. The purpose of this study was to determine the mean international normalised ratio in patients diagnosed with valvular heart disease who had had mechanical valve replacement and were on anti-coagulant medication.

METHODOLOGY: Between the dates of 28 July 2020 and 28 January 2021, the research was carried out at the Department of Cardiology at the Punjab Institute of Cardiology in Lahore. After the inclusion criteria were satisfied, a total of 250 patients were enrolled. Consent after being fully informed was obtained, as well as demographic information. Then patients underwent surgery. After 3rd month patients were given standard anti-coagulation therapy as per hospital protocol. On each visit, blood sample was taken by using 3cc disposable syringe and sent to the laboratory of the hospital for assessment of INR and serial values of INR.

RESULTS: The mean age of the patients was 42.51±16.59 years, there were 149(59.60%) patients were male. Hypertension and diabetes mellitus was found in 103(41.2%) & 75(30%) patients respectively. After 3rd month the mean INR value of patients was 2.245±0.4016.

CONCLUSION: According to this study the mean international normalized ratio was 2.245±0.4016 with anti-coagulation use after mechanical valve replacement in patients with valvular heart disease

Author Biographies

Hurmah Shoaib, Punjab Institute of Cardiology, Lahore

Postgraduate resident cardiology

Mahrukh Mansoor Khosa, Punjab Institute of Cardiology, Lahore

Postgraduate Resident Cardiology

Syed Ali Hamza, Punjab Institute of Cardiology, Lahore

Medical Officer Cardiology

Fizza Mobasher, Punjab Institute of Cardiology, Lahore

Postgraduate Resident Cardiology

Ali Nasir, Punjab Institute of Cardiology, Lahore

Medical Officer Cardiology


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