Objectives: The aim of this study was to evaluate the progress of corrected Thrombolysis in Myocardial Infarction (TIMI) frame count (CTFC) and perfusion grade in heart transplant recipients and whetherCTFC could predict mortality and correlate with intravascular ultrasound parameters.Background: The conventional angiography couldnt detect the early transplant vasculopathy as well as intravascular ultrasound (IVUS).Although, IVUS can detect early transplant vasculopathy and predict long-term mortality, it cant assess the coronary microvascular system.TIMI frame count and TIMI myocardial perfusion grade can assess coronary flow and myocardial perfusion in coronary angiography.Methods: Sixty-two heart transplant recipients were enrolled this study.All the patients coronary angiographies were evaluated for TIMI frame count and perfusion grade (TMPG) at one month after transplantation as a baseline and at one year and five years later as a follow-up.Thirty-seven of the patients underwent coronary angiography at baseline, one-year, and five-year follow-up.The patients were divided into two groups according to presence or absence of increasing global corrected TIMI frame count (gCTFC: average of CTFCs of three coronary arteries) from baseline to one-year follow-up.Fifty vessels in 35 patients were volumetric analyzed with IVUS at both baseline and oneyear follow-up.Rejection status and mortality rate of the patients were evaluated during the follow-up period.The progression of CTFC and TMPG was investigated from baseline to one and five year follow-up.IVUS parameters and change in gCTFC from baseline to one-year were analyzed for correlation.Results: The mean age was 55.06±10.0 years for those enrolled in our study.Twenty-nine (46.8%) of them were female.The gCTFC and CTFCs of all three coronary arteries significantly increased from baseline during follow-up (p<0.0001).Also, TMPGs deteriorated significantly (p<0.0001 for LAD and circumflex, p=0.002 for RCA).The mean followup time was 51.47±17.2 months (range 12.23 to 78.43 months).Only percent change in vessel volume and percent change in average external elastic membrane cross-sectional area of all the IVUS parameters, were found to be significantly but weakly correlated with change in gCTFC.The baseline characteristics of both groups, with and without gCTFC increase, were comparable.The number of the episodes of * 3A were found significantly higher in the nonincreasing gCTFC group (p=0.03).The mortality rate was significantly higher in the increasing gCTFC group (p=0.02) Conclusion: The gCTFC and CTFCs of all the coronary arteries increased and the TMPG deteriorated in heart transplant recipients during follow-up.The mortality rate was significantly higher in patients whose gCTFC increased from baseline to follow-up.The change in gCTFC could be objective, quantitative, and a simple predictor for long-term mortality of heart transplant recipients.