Regional wall motion abnormalities in ICU patients with non-obstructed coronary arteries

Abstract

Introduction: Left ventricular dysfunction is associated with high mortality and can be both global or due to regional wall motion abnormalities (RWMA). RWMA is most commonly caused by obstructed coronary arteries (myocardial infarction) but conditions with non-obstructed coronary arteries do exist and are a modestly explored subject, especially in the ICU environment. Objectives: The aim of this work was to verify the existence and estimate the incidence of RWMA with nonobstructed coronary arteries, to characterize the patients of this group and compare them to patients with ischemic heart disease. Proving that RWMA seen in ICU patients can be caused by conditions with non-obstructed coronary arteries as well as myocardial infarction. Methods A retrospective study was performed by combining the Angiography (SCAAR) register with the ICU administration system. All patients admitted to the ICU over a seven-year period of time, who performed and angiography during their hospital admission period was reviewed. Giving, in combination with echocardiography the following groups: RWMA with non-obstructed coronary arteries, RWMA with obstructed coronary arteries and normal cardiac function with non-obstructed coronary arteries. Results: Out of the 260 patients with RWMA, 56 (22%) patients had non-obstructed coronary arteries. These patients were younger, more likely to be woman, more likely to have a history of substance or alcohol abuse but less likely to have comorbidities, in comparison to patients with obstructed coronary arteries. There was no significant difference in mortality between the groups. Out of the 56 patients with non-obstructed coronary arteries 40 patients had focal, or a combination of focal and apical RWMA, the remaining 16 patients had circumferential RWMA with either apical or midventricular pattern. A majority of the 56 patients lacked a definitive diagnosis and the most commonly suggested diagnosis was Takotsubo syndrome. Conclusion: RWMA with non-obstructed coronary arteries exists in the ICU population and is possibly are more common explanation for hypokinesia than previously suggested. Most patients do not get a definitive diagnosis with the methods we use today, indicating that differential diagnosis in this group is challenging. A majority of patients presented with focal hypokinesia, indicating that non-ischemic conditions should be suspected in patients with focal RWMA as well as circumferential RWMA. This paper serves as a proof of concept that RWMA with non-obstructed coronary arteries exist in the ICU population. Though, prospective studies are required to characterize this group further and to get a more correct estimation of the prevalence.