Relação entre o perfil tensional noturno e a prevalência e gravidade da retinopatia hipertensiva

Could aortic arch calcification help in detection of hypertensive retinopathy?

OBJECTIVE

Hypertension-induced end-organ damage is one of the important determinants of morbidity and mortality in patients with hypertension. All types of hypertension-induced end-organ damages start with vascular damage. Vascular calcification is a marker of vascular damage and aortic arch calcification (AAC) is one of the easily identifiable types of vascular calcification. We hypothesized that AAC predicts retinopathy in hypertensive patients.

METHODS

Consecutive hypertensive patients without diabetes mellitus were included. Chest radiography in the posterior-anterior was used to assess the presence of AAC. All patients underwent ophthalmologic examination for retinopathy.

RESULTS

We included 495 hypertensive patients in this study. Of these, 306 (62%) had hypertensive retinopathy. Patients with hypertensive retinopathy had significantly higher prevalence of AAC as compared to the patients without hypertensive retinopathy (88% vs. 22%, P < 0.001). We found a strong and positive correlation between hypertensive retinopathy and AAC grades (r = 639, P < 0.001). Receiver operator characteristics curve analysis yielded a strong predictive ability of AAC for the presence of hypertensive retinopathy [area under curve = 0.814, 95% confidence interval (CI): 0.775-0.853, P < 0.0001]. In multivariate logistic regression analysis, presence of AAC [odds ratio (OR) 13.128; CI: 7.894-21.832] and serum glucose levels (OR 1.020; CI: 1.003-1.037) were strongly and independently associated with hypertensive retinopathy.

CONCLUSION

Presence of AAC on chest radiograph is strongly and independently associated with retinopathy in nondiabetic hypertensive patients. This simple, inexpensive and widely available tool may help in early detection of retinopathy in patients with hypertension.

Extreme dipping: is the cardiovascular risk increased? An unsolved issue

: Extreme dipping (i.e. a marked blood pressure fall during night-time period) is an alteration of circadian blood pressure (BP) rhythm frequently observed in the setting of systemic hypertension as well as in the general population. Some reports have suggested that cardiovascular prognosis in extreme dippers (ED) is similar as in dippers, whereas other studies have documented either a better or worse prognosis in ED. Available information on clinical and prognostic implications of ED is scanty and data provided by studies are controversial. Furthermore, a comprehensive report summarizing the key features of this BP pattern is lacking. The present review focuses on a number of issues concerning ED pattern such as the prevalence and clinical correlates, mechanisms underlying this BP phenotype association with hypertension mediated organ damage (HMOD) and prognostic value in predicting cardiovascular events and all-cause mortality. The reported prevalence of this BP rhythm alteration ranges from 5% to 30%, depending on diagnostic criteria, clinical and demographic characteristics of subjects. Most studies targeting the association of this condition with HMOD failed to find consistent findings in support of an adverse impact of ED on vascular, renal of cardiac structure and function. Available data on ED as compared to low risk reference group (i.e. dippers) do not allow to conclude that high BP variability resulting from a marked BP fall at night adversely affects cardiovascular prognosis at the community level and in the general hypertensive population. Thus, further studies aimed to assess the prognostic significance of ED as well as the impact of therapeutic interventions aimed to normalize this circadian BP pattern, are highly needed.

A comparative evaluation of the efficacy of dimethylaminoethanol derivative 7–16, C7070 and picamilon in correction of experimental hypertensive neuroretinopathy

Introduction. The efficacy of dimethylaminoethanol (DMAE) derivative 7–16, substance C7070 in comparison with picamylon in hypertensive neuroretinopathy model in white laboratory rats was evaluated.

Materials and methods. For measuring the blood pressure, a system of noninvasive blood pressure measurement in small animals NIBP200 was used. Ophthalmoscopy was performed by using Bx a Neitz ophthalmoscope (Japan) and Osher MaxField 78D lens, OI-78M model. Electroretinography (ERG) was recorded in response to a single stimulation. Biopotentials were presented graphically on the screen with the help of BIOPAC SYSTEMS MP-150 with ACQKNOWLEDGE 4.2 software (USA). To assess a degree of a functional retinal disorder, the b/a coefficient was used.

Results and discussion. The most pronounced protective effect on the model of hypertensive neuroretinopathy is demonstrated by C7070, which is expressed in the notable approximation to the normal eye fundus image and reaching the target values of the b/a coefficient. In the group with correction by DMAE derivative 7–16, a protective effect is observed, which exceeds picamilon, which is expressed in the elimination of soft and solid exudates, vein and venule plethora, vascular tortuosity, arterial spasm, Salus-Gunn I symptom, hemorrhages; the b/a increases significantly by 26% compared to the group without correction (p &lt; 0.05).

Conclusion. The eye fundus image and functional state of the retina are completely restored when correcting experimental hypertensive neuroretinopathy with C7070 in a dose of 50 mg/kg to laboratory rats and partially restored when correcting with DMAE derivative 7–16 in a dose of 25 mg/kg, which in both cases exceeds the protective effect of the reference drug picamilon on the model of hypertensive neuroretinopathy.