Objective: Delayed myocardial enhancement is caused by a variety of cardiovascular diseases. The extent of the enhanced area has been examined by the inversion recovery (IR) method, whereby at the inversion time (TI), normal myocardium shows a low signal intensity. In this sequence, as pericardial fat shows a very high intensity, a delayed enhancement just below the pericardium may be indistinct. To improve the accuracy of delayed myocardial enhancement, we employed the spectral presaturation of inversion recovery (SPIR) method.
Materials and methods: Thirty-five patients with symptoms of cardiovascular disease aged between 36 and 80 years old (mean age, 62 years old) were investigated. Thirty were men and five were women. Inversion recovery and SPIR images were obtained 25 min after initial administration of a gadolinium-based contrast material. Each TI, when the signal intensity of the normal myocardium was null, was determined by images obtained at serial different TIs. A radiologist and a cardiologist examined each image by a consensus reading. The extent of myocardial enhancement was described as none, subendocardial, transmural and a random pattern in each case. Images were ranked over three levels and were based on whether myocardial enhancement could be easily detected or whether the contour of the myocardium was visualized precisely. Student's t-test was conducted to compare the quality of two sequences in all patients and in 22 patients who showed delayed myocardial enhancement.
Results: The imaging quality in evaluating delayed myocardial enhancement in all patients was superior with IR compared with SPIR, although it was not statistically significant. The imaging quality in the patients with delayed myocardial enhancement was similar between SPIR and IR. SPIR was superior to the IR sequence in two of the four patients who exhibited transmural enhancement.
Conclusion: SPIR exhibited equivalent image quality to IR in evaluating delayed myocardial enhancement. As it has the potential advantage in patients with rich adipose tissue surrounding the myocardium, it can be an alternative sequence to evaluate myocardial viability.