Evaluating an Admission Inflammatory Biomarker as an Independent Risk Factor for Malperfusion Syndromes in Acute Type A Aortic Dissection

A. Crawford. Mills¹, G. Estrera², A. Tanaka², H. Sandhu³, C. Miller⁴, S. Eisenberg⁵, A. Estrera^6
1UTHealth McGovern Medical School, Pearland, Texas ²McGovern Medical School at UTHealth, Houston, Texas ³McGovern Medical School, UTHealth at Houston, HOUSTON, Texas ⁴McGovern Medical School, UTHealth Houston, Houston, Texas ⁵University of Texas Health Science Center, Houston, Texas ⁶UTHealth Houston McGovern Medical School, Memorial Hermann Heart and Vascular Institute, Houston, Texas

Purpose: Neutrophil-to-lymphocyte ratio (NLR) is an inexpensive inflammatory biomarker calculated from a complete blood cell count. Increasing NLR has been shown to portend worse outcomes in cardiovascular disease. We sought to evaluate the diagnostic utility of admission NLR values in patients presenting with acute type A aortic dissection (ATAAD) with malperfusion.

Methods: We retrospectively evaluated 644 consecutive patients presenting with ATAAD who underwent surgical repair from 2001 to 2020 at a single institution. Admission NLR values were calculated. Patients were divided into groups presenting before or after 12 hours from symptom onset. Associations between admission NLR values and cerebral, coronary, gastrointestinal, renal, and lower extremity malperfusion syndromes were analyzed by comparing the median NLR values for each group. Median values of admission NLR was used for univariate regression models for different malperfusion syndromes.

Results: 583 patients (90.5%) had admission NLR values. Of these, 256 (43.9%) had malperfusion syndromes, which were cerebral malperfusion (43,4%), coronary malperfusion (18.4%), gastrointestinal malperfusion (26.6%), renal malperfusion (49.6%), and lower extremity malperfusion (40.6%). 124 patients (48.4%) had malperfusion to two or more vascular beds. Additionally, 253 patients (43.4%) presented after 12 hours from symptom onset, with 103 being malperfusion patients (40.2%). Median NLR values were significantly different between patients with or without malperfusion if they presented after 12 hours from symptom onset (8.0 vs. 6.8, p=0.005) compared to within 12 hours (7.7 vs. 6.9, p=0.427). This was more noticeable in patients presenting after 12 hours with lower extremity malperfusion (8.6 vs. 6.9, p< 0.001; Figure) and malperfusion to two or more vascular beds (9.2 vs. 6.9, p=0.032; Figure). Using a median NLR value of 7.1 as a cutoff point, univariate analysis showed this value as a predictor for all malperfusion syndromes, renal malperfusion, lower extremity malperfusion, and malperfusion to two or more vascular beds (Table). There were trends towards higher NLR values in cerebral and gastrointestinal malperfusion, too, but not coronary malperfusion.

Conclusion: NLR appears to be useful in delineating ATAAD patients with possible malperfusion, and it can be used as an adjunct to other diagnostic information. A continued high NLR after 12 hours from symptom onset more strongly correlates with malperfusion, especially lower extremity malperfusion or malperfusion to multiple vascular beds.

Identify the source of the funding for this research project: none