Valor pronóstico de la gammagrafía de perfusión miocárdica con 201Tl normal en el postinfarto agudo de miocardio

Objective

The purpose of this work has been to determine the prognostic value of normal thallium-201 myocardial perfusion scintigraphy (MPS) in patients who had suffered myocardial infarction in the three months prior to the examination.

Material and methods

A stress test followed by ²⁰¹Tl Gated SPECT was performed. A follow-up was made of 63 patients with normal perfusion scintigraphy. According to the MPS results, the patients were divided into 2 groups. Group I (n = 63; 57% males, age 65 ± 12), patients with normal MPS, and group II (n = 60; 81% males, age 64 ± 10), patients with abnormal MPS. The appearance of a new infarction or cardiac death occurring during this period (63 ± 3 months) was analyzed. The appearance of events was related with the cardiovascular risk factors, perfusion study and ventricular function.

Results

Five events occurred in group I in 4 patients: 3 new infarctions and 2 cardiac deaths. In group II, there were 18 events in 14 patients: 8 new infarctions and 10 cardiac deaths (p < 0,0001). The events were related with age, time from MPS, diabetes, size of perfusion defect and post stress ventricular ejection fraction. Mean survival en group I was 108 months (103–112) and in group II 97 (88–107) (p = 0,01).

Conclusion

Patients with normal MPS had fewer major events than patients with abnormal MPS. The size of MPS has been related with the appearance of events. A depressed post-stress left ventricular ejection fraction has a poor prognosis.