Prognostic value of heart rate reserve in patients with suspected coronary artery disease undergoing stress myocardial perfusion imaging

Figure 1. Risk-adjusted survival curves for patients across HRR quartile. On the basis of the multivariable model including age, gender, diabetes, and METS, a significant difference in survival as a function of HRR quartile was observed

Figure 2. Survival curves by Kaplan-Meier according to heart rate reserve (HRR) value

Figure 3. Event-free survival curves by Kaplan-Meier in patients grouped according to heart rate reserve (HRR) and summed difference score (SDS) cut-offs. Group 1: HRR ≥ 67% and SDS < 5%; group 2: HRR < 67% and SDS < 5%; group 3: HRR ≥ 67% and SDS ≥ 5%; group 4: HRR < 67% and SDS ≥ 5%

Figure 4. Annualized event rates in patients grouped according to heart rate reserve (HRR) and summed difference score (SDS) cut-offs. *P < .01 group 1 vs the other three groups; †P < .01 group 2 vs group 4. The annualized event rates (% person-years) were 0.74 in group 1, 1.44 in group 2, 2.61 in group 3, and 4.22 in group 4

Figure 5. Estimated adjusted hazard ratios for heart rate reserve (HRR) in relation to time to death by gender, considering the interaction between HRR and gender

Figure 6. Bar graph illustrating the incremental prognostic value of heart rate reserve (HRR) over clinical data and summed difference score (SDS) for identifying patients at risk of event. The addition of HRR significantly improved the power of the model increasing the global χ2 value from 76.2 to 82.7

Figure 7. Age-adjusted annualized event rate in patients grouped according to heart rate reserve (HRR) and summed difference score (SDS) cut-offs. Panel A female and panel B male. Group 1: HRR ≥ 67% and SDS < 5%; group 2: HRR < 67% and SDS < 5%; group 3: HRR ≥ 67% and SDS ≥ 5%; group 4: HRR < 67% and SDS ≥ 5%