Acute global longitudinal strain evaluation in patients with subacute to chronic chest pain: A pilot, observational study.

BACKGROUND: Global longitudinal strain (GLS) imaging is a multifaceted modality that has been utilized in various fields of clinical cardiology in the recent past; however, its implementation for the assessment of ischemia has been limited.

OBJECTIVES: This study aimed to document the functional changes in GLS secondary to acute myocardial ischemia in patients with chronic chest pain.

METHODS: In this unblinded, single-center, investigator-initiated, prospective pilot study, the functional changes in GLS at baseline, during, and immediately following coronary percutaneous intervention were monitored in 10 ambulatory patients who underwent elective catheterization. The exclusion criteria included a low ejection fraction, or a history of chemoradiation, myopathy, and congenital heart disease.

RESULTS: The average GLS at baseline, during the balloon intervention (BI), and 1-2 min after BI was -15.4 % ± 3.3 %, -10.2 % ± 3.6 %, and -16.1 % ± 4.2 %, respectively. The average GLS decreased significantly by 5.1 % (95 % CI, -7.9 % to -2.3; P = 0.0013) from baseline to BI, increased by 6.3 % (95 % CI, 3.7 % to 8.9 %; P < 0.001) from BI to immediately post-BI, and increased by 0.7 % from baseline to post-BI (95 % CI, -0.4 % to 2.7 %; P = 0.161).

CONCLUSION: Patients undergoing BI showed a significant decrease in the average GLS within 1-2 min of BI, with GLS returning to baseline subsequently, clearly demonstrating the efficacy of the modality and the clinical significance of data obtained. These functional changes replicate cardiac perfusion to the segments supplied by respective vessels and its effect with reperfusion or ballooning. The slight increase in GLS from baseline to post-intervention was not statistically significant, which could be attributed to the confounding factors. Analyzing our data, we can safely conclude that GLS is potentially a sensitive, temporal, and quantitative tool for identifying patients with acute ischemia with its limitations and need for further perfection of this modality. Therefore, GLS assessments on 2D echo can be used for risk stratification of patients with subacute to chronic chest pain concerning for ischemia in addition to EKG, troponins and other data obtained by non-invasive testing and evaluation.