Myocardial Perfusion Gated SPECT in Prognostic Stratification of Egyptian Population with Suspected Ischemic Heart Disease

Nasr, Hatem

doi:10.21608/egyjnm.2012.5471

Myocardial Perfusion Gated SPECT in Prognostic Stratification of Egyptian Population with Suspected Ischemic Heart Disease

Document Type : Original Paper, Cardiology

Author

Hatem Nasr

Nuclear Medicine, Faculty of Medicine, Cairo University, Egypt.

10.21608/egyjnm.2012.5471

Abstract

Background: Evaluation of the left ventricular perfusion and function is important in clinical cardiology. Quantifying the degree and extent of functional abnormalities of the left ventricle permits a systematic assessment of the disease state. Gating provides additional information that cannot be obtained by perfusion imaging alone. The diagnostic role of myocardial perfusion gated SPECT in patients with coronary artery diseases is well recognized, however its role in risk stratification, and prognostication is still growing.
Objective: To assess the feasibility of 99mTcMIBI myocardial perfusion gated SPECT (GSPECT) in prognostic risk stratification of an Egyptian population with known or suspected coronary artery disease.
Methods: Clinical data and SPECT results were analyzed in 165 consecutive patients that were monitored for mean follow up period of 13.8 ± 5.3 months. Semi quantitative visual scoring of perfusion and function was performed while post-stress EF, EDV and ESV were automatically generated. Multivariate Cox proportional hazards regression models were used to identify independent predictors of cardiac events while survival analysis was performed using Kaplan-Meier method.
Results: Perfusion findings were abnormal in 98 patients. During follow-up, death occurred in 5 patients; nonfatal myocardial infarction in 14; coronary revascularization in 48 and unstable angina in 4 patients. In multivariable Cox proportional hazards model, DM (p=0.002), previous MI (p=0.029), and reduced EF (p<0.001) were independent predictors for major events (death and MI), while independent predictors for total events include the same parameters in addition to high cholesterol level (p=0.015) and number of both normal and ischemic segments (p=0.001). Patients with history of DM, previous MI and EF<50% had reduced event free survival. Patients with low EF<35% and those with multivessel disease were at higher risk and had shorter event free survival.
Conclusion: Myocardial perfusion gated SPECT parameters are considered not only a powerful independent predictors for cardiac events but also have an incremental prognostic value over the pre scan clinical variables for risk stratification in Egyptian patients with known or suspected CAD.

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