Impaired retinal capillary perfusion assessed by optical coherence tomography angiography in patients with recent systemic hypertensive crisis

Abstract

Purpose : Hypertensive crisis is a potentially life-threatening event associated with an increased risk of stroke, acute heart failure and aortic dissection. Impairment of the microvasculature is known to be involved in possible end-organ damage. To our knowledge, retinal perfusion after hypertensive crisis has not been investigated in vivo yet but could be of prognostic value for these patients. In this study, we quantified retinal microvascular changes in subjects post hypertensive crisis compared to a control group using optical coherence tomography angiography (OCTA).

Methods : 10 patients with a recent history of hypertensive crisis (systolic blood pressure ≥ 180 mmHg and/or diastolic blood pressure ≥ 110 mmHg, ≤ 7 days before examination) and 18 age-matched controls without arterial hypertension, a history of hypertensive crisis or cardiovascular events were assessed with 3x3mm OCTA scans of the macula (PLEX Elite 9000, Carl Zeiss Meditec Inc.). Subjects with known retinal or choroidal pathology, a history of glaucoma or diabetes were excluded. The outcome parameters were: Vessel density (VD), skeleton density (SD) and vessel diameter index (VDI) of the superficial and deep retinal layers (S-RL, D-RL) and mean and standard deviation (SD) of the choriocapillaris layer (CC), as measured in ImageJ.

Results : The mean age of the patients was 58 ± 16 years and the mean age of the controls was 59 ± 14 years (p = 1.0). The highest measured blood pressure was 250 mmHg systolic and 141 mmHg diastolic in patients. On OCTA, Skeleton Density in the Superficial RL (p = 0.019), Vessel Density in the Deep RL (p = 0.010) and Skeleton Density in the Deep RL (p = 0.001) were reduced in the hypertensive crisis group. The other parameters (VD of the S-RL, VDI of the S-RL and D-RL, mean, SD of gray values of the CC) did not differ significantly.

Conclusions : Hypertensive crisis leads to retinal capillary dropout which can be quantified using OCTA. This non-invasive imaging modality may, therefore, allow for monitoring vascular damage post hypertensive crisis. Further studies are needed to establish for how long capillary dropout persists and whether or not it is associated with macrovascular complications and/or end-organ damage.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.