Uncontrolled risk factors and worsening perfusion pattern on SPECT myocardial perfusion imaging in medically treated patients with stable chronic ischaemic heart disease.

PURPOSE: Few data exist on the correlation between the effectiveness of risk factor control and the evolution of myocardial perfusion over time in patients with stable ischaemic heart disease. The aim of the study was to evaluate the changes in stress-rest myocardial perfusion in medically treated patients with stable chronic ischaemic heart disease and the relationship with risk factor control.
METHODS: The study cohort included 174 consecutive patients (age 60 ± 9 years, 68 % men) undergoing stress-rest myocardial perfusion imaging (MPI) (study 1), who also underwent repeat evaluation (study 2) and who were clinically stable on medical therapy. Summed stress, rest and difference scores were calculated. According to the evolution of perfusion pattern from study 1 to study 2, patients were classified as improved, stable or worsened.
RESULTS: Study 2 was performed on average 2.7 years after study 1. Of the 174 patients, 47 (26.9 %), 53 (30.8 %) and 74 (42.5 %) were classified as stable, improved and worsened, respectively. A significant trend was observed between the number of risk factors at the time of study 1 and worsening of myocardial perfusion (24 % of patients with zero or one risk factor showed worsening, 31 % with two, and 59 % with three or more; p = 0.03). Moreover, patients with worsened perfusion had a higher number of poorly controlled risk factors.
CONCLUSION: Despite medical therapy and clinical stability, myocardial perfusion worsened in 42.5 % of patients. The risk profile was reclassified in half of the patients. Worsening occurred more frequently in patients with three or more risk factors at the time of study 1 and in those with poorly controlled risk factors at the time of study 2; in this subset of patients, even if clinically stable, reassessment after 2 years could be considered.