North Downs, Specialist Referrals, 3 & 4 The Brewerstreet Dairy Business Park, Brewer Street, Bletchingley, UK.
The London Cat Clinic, Bermondsey, London, UK.
J Feline Med Surg. 2021 Dec;23(12):1129-1139. doi: 10.1177/1098612X21997629. Epub 2021 Mar 19.
Early diagnosis of arterial hypertension is essential to prevent target organ damage. In humans, retinal arteriolar narrowing predicts hypertension. This blinded prospective observational study investigated the retinal vessel diameters in senior and geriatric cats of varying systolic blood pressure (SBP) status and evaluated retinal vascular changes in hypertensive cats after treatment.
Cats with a median age of 14 years (range 9.1-22 years) were categorised into five groups: group 1, healthy normotensive (SBP <140 mmHg; n = 40) cats; group 2, pre-hypertensive (SBP 140-160 mmHg; n = 14) cats; group 3, cats with chronic kidney disease (CKD) and normotensive (n = 26); group 4, cats with CKD and pre-hypertensive (n = 13); and group 5, hypertensive cats (SBP >160 mmHg, n = 15). Colour fundus images (Optibrand ClearView) were assessed for hypertensive lesions. Retinal vascular diameters and bifurcation angles were annotated and calculated using the Vascular Assessment and Measurement Platform for Images of the Retina annotation tool (VAMPIRE-AT). When available, measurements were obtained at 3 and 6 months after amlodipine besylate treatment.
Ten hypertensive cats had retinal lesions, most commonly intraretinal haemorrhages and retinal exudates. Arteriole and venule diameters decreased significantly with increasing age (-0.17 ± 0.05 pixels/year [ = 0.0004]; -0.19 ± 0.05 pixels/year). Adjusted means ± SEM for arteriole and venule diameter (pixels) were 6.3 ± 0.2 and 8.9 ± 0.2 (group 1); 7.6 ± 0.3 and 10.1 ± 0.4 (group 2); 6.9 ± 0.2 and 9.5 ± 0.3 (group 3); 7.4 ± 0.3 and 10.0 ± 0.4 (group 4); and 7.0 ± 0.3 and 9.8 ± 0.4 (group 5). Group 1 arteriole and venule diameters were significantly lower than those of groups 2 and 4. Group 2 arteriole bifurcation angle was significantly narrower than those of groups 1 and 3. Post-treatment, vessel diameters decreased significantly at 3 and 6 months in seven hypertensive cats.
Increased age was associated with reduced vascular diameters. Longitudinal studies are required to assess if vessel diameters are a risk indicator for hypertension in cats.
早期诊断动脉高血压对于预防靶器官损伤至关重要。在人类中，视网膜小动脉狭窄预示着高血压。本项盲法前瞻性观察研究调查了不同收缩压（SBP）状态的老年和老年猫的视网膜血管直径，并评估了治疗后高血压猫的视网膜血管变化。
研究对象为年龄中位数为 14 岁（范围 9.1-22 岁）的猫，分为 5 组：第 1 组，健康的血压正常（SBP<140mmHg；n=40）猫；第 2 组，血压正常的（SBP 140-160mmHg；n=14）的预高血压猫；第 3 组，慢性肾病（CKD）和血压正常（n=26）的猫；第 4 组，CKD 和预高血压（SBP 140-160mmHg；n=13）的猫；第 5 组，高血压（SBP>160mmHg，n=15）猫。使用 Optibrand ClearView 对眼底图像进行高血压病变评估。使用血管评估和视网膜图像测量平台（VAMPIRE-AT）的血管直径注释和计算工具对视网膜血管直径和分叉角度进行注释和计算。当有可用数据时，在苯磺酸氨氯地平治疗 3 个月和 6 个月后进行测量。
10 只高血压猫出现视网膜病变，最常见的是视网膜内出血和视网膜渗出。随着年龄的增长，小动脉和小静脉直径显著减小（-0.17±0.05 像素/年[=0.0004]；-0.19±0.05 像素/年）。调整后的平均 SEM 小动脉和小静脉直径（像素）分别为 6.3±0.2 和 8.9±0.2（第 1 组）；7.6±0.3 和 10.1±0.4（第 2 组）；6.9±0.2 和 9.5±0.3（第 3 组）；7.4±0.3 和 10.0±0.4（第 4 组）；和 7.0±0.3 和 9.8±0.4（第 5 组）。第 1 组的小动脉和小静脉直径明显低于第 2 组和第 4 组。第 2 组的小动脉分叉角度明显小于第 1 组和第 3 组。在 7 只高血压猫中，治疗后 3 个月和 6 个月时，血管直径显著下降。
年龄增长与血管直径减小有关。需要进行纵向研究以评估血管直径是否是猫高血压的风险指标。
