Background and Objective: The cardiac scintigraphy is worthwhile to detect ischemia instead of cardiac catheterization, whereas the echocardiogram is useful to detect movement of myocardium and valves but not to detect ischemia. It is beneficial to predict ischemia by echocardiogram because the disadvantage of cardiac scintigraphy is to be expensive and to expose radiation. The objective of the current study is to evaluate whether the echocardiogram is substituted for the cardiac scintigraphy in the patients with ischemic heart disease and to assess the effect of hypertension on the correlation of two examinations. Methods: We recruited 101 patients with ischemic heart disease who were admitted to Chidoribashi General Hospital and underwent both echocardiogram and cardiac scintigraphy from April 2021 to March 2023. They were divided to two groups by the presence and absence of hypertension at admission. The various parameters of echocardiogram and cardiac scintigraphy were collected retrospectively. The correlation was statistically tested using JMP Pro 17. This study was approved by our ethical committee. Results: In the risk factors of poor prognosis, left ventricular end-systolic volume, summed stress score and ejection fraction (EF) from cardiac scintigraphy were correlated with left ventricular internal dimension (LVD) on echocardiogram. In contrast, summed difference score was correlated with LVD in systole and EF on echocardiogram in the patients without hypertension but not in the patients with hypertension. Conclusions: These results suggest that LVD of echocardiogram may become an indicator to detect cardiac ischemia instead of cardiac scintigraphy.