Study design
Between January 2015 and December 2020, 652 consecutive patients underwent an isolated AVR procedure at the Clinical Centre of Serbia in Belgrade. This observational analysis included elective, urgent, and emergent cases performed due to any pathology. Combined surgery was the exclusion criterion. Forty-six patients refused to participate in research, while 11 patients were lost to follow-up (Fig. 1).
Patients were divided into two groups according to whether they had received a biological or mechanical prosthesis. Furthermore, they were evaluated for the presence or absence of PPM. The groups with and without PPM present were compared with regard to baseline characteristics, operative characteristics, survival, complications, freedom from angina and QoL up to 6 years of follow-up. The data were obtained from medical records and via telephone surveys during the follow-up period.