Effect of hospitalization on 24-h ambulatory blood pressure of hypertensive patients

Carotid Artery Revascularization Improves Cardiac Sympathetic Nerve Activity in Patients With Carotid Artery Stenosis

BACKGROUND

The carotid sinus baroreceptor reflex controls the neural regulation of blood pressure. Baroreceptor disorders due to carotid sinus atherosclerosis have detrimental cardiovascular effects. This study investigated the medium-term effects of carotid artery revascularization (CAR) on sympathetic and cardiac function and systemic blood pressure variability in patients with carotid artery stenosis.

METHODS

This study included 21 consecutive patients (median age 70 years, 18 men) with carotid artery stenosis scheduled for CAR. ¹²³I metaiodobenzylguanidine (MIBG) scintigraphy, echocardiography, brain natriuretic peptide levels, 24-h Holter electrocardiography (ECG), and ambulatory blood pressure monitoring assessed approximately 3 months postoperatively were compared to preoperative data.

RESULTS

All 21 enrolled patients underwent CAR. Carotid artery stenting was done in three patients with cardiovascular risk or anatomical difficult for carotid endarterectomy. The mean common carotid artery end-diastolic velocity improved significantly (P < 0.01) by 1.6-fold, from 10.8 ± 3.2 to 16.1 ± 7.1 cm/s. In ¹²³I-MIBG scintigraphy, the heart-to-mediastinum (H/M) count ratio was significantly higher than preoperatively (from 2.66 ± 0.48 to 2.86 ± 0.56, P = 0.03). Holter ECG analysis revealed a significant decrease in the low-frequency/high-frequency (LF/HF) ratio compared to preoperatively (from 2.17 ± 1.20 to 1.62 ± 0.68, P = 0.04). These findings suggest decreased myocardial sympathetic activation. In echocardiography, the tissue Doppler-derived e' increased, and E/e' decreased significantly (P < 0.05) from 11.7 ± 5.1 to 10.1 ± 4.0, suggesting an improved left ventricular diastolic capacity. The mean 24-h and nighttime blood pressures were unchanged.

CONCLUSIONS

CAR in patients with carotid stenosis may provide medium-term improvement in cardiac sympathetic nerve activity and left ventricular diastolic dysfunction.

Ocular Perfusion Pressure and Severity of Glaucoma: Is There a Link?

Aim and objective

To establish the association between 12-month inter-visits ocular perfusion pressure (OPP) and severity of glaucoma.

Materials and methods

A total of 164 eyes (60 primary open-angle glaucoma, 52 normal-tension glaucoma, and 52 primary angle-closure glaucoma) of 164 patients were analyzed in this prospective cohort study. Patients who demonstrated good compliance to treatment were recruited. The severity of glaucoma was stratified according to the Advanced Glaucoma Intervention Study (AGIS) score based on reliable and reproducible visual field analysis at baseline. OPP was obtained at baseline and a 3-monthly follow-up visit over a 12-month duration. The pattern and fluctuation of mean OPP were studied. Repetitive measure ANOVA and one-way ANOVA were used for statistical analysis.

Results

The inter-visits mean OPP (p = 0.010), systolic OPP (p = 0.020), diastolic OPP (p = 0.010), systolic blood pressure (p = 0.040), and diastolic blood pressure (p = 0.006) showed significant difference with severity of glaucoma. There was no significant difference between mean inter-visits intraocular pressure (IOP) and severity of glaucoma (p = 0.410). The end-stage glaucoma group had the lowest mean OPP and widest inter-visit mean OPP fluctuation. Early and mild glaucoma patients demonstrated higher mean OPP compared with moderate, severe, and end-stage glaucoma.

Conclusion

There is a significant association between OPP and the severity of glaucoma. Balancing blood pressure and IOP is important in optimizing adequate perfusion and prevent further damage to the optic nerve head.

How to cite this article

Ch'ng TW, Chua CY, Ummi Kalsom MA, et al. Ocular Perfusion Pressure and Severity of Glaucoma: Is There a Link? J Curr Glaucoma Pract 2021;15(2):78–85.

In-hospital day-by-day systolic blood pressure variability during rehabilitation: a marker of adverse outcome in secondary prevention after myocardial revascularization

OBJECTIVE

Although it is known that increased visit-to-visit or home day-by-day variability of blood pressure (BP), independently of its average value, results in an increased risk of cardiovascular events, the prognostic value of in-hospital day-by-day BP variability in secondary cardiovascular prevention has not yet been established.

METHODS

We studied 1440 consecutive cardiac patients during a cardiovascular rehabilitation program of about 12 days after coronary artery bypass graft (CABG) and/or valve surgery. We measured auscultatory BP at the patient bed in each rehabilitation day twice, in the morning and the afternoon. We correlated SBP variability assessed as standard deviation (SBP-SD) and coefficient of variation (SBP-CoV) of the daily measures with overall mortality, cardiovascular mortality and major adverse cardiocerebrovascular events (MACCEs) after a mean follow-up of 49 months by Cox hazard analysis.

RESULTS

In our patients (age 68 ± 11years, 61% hypertensive patients) the ranges of SBP-SD tertiles were: 4.1-9.1, 9.2-11.5 and 11.6-24.5 mmHg. Fifty-five percent of the patients underwent CABG, 33% underwent valve surgery, 12% both CABG and valve surgery. In CABG patients, the highest SBP-SD tertile showed the highest overall mortality, cardiovascular mortality and MACCEs (P < 0.01). Results remained significant after multivariate analysis adjusting for age, sex, mean SBP, BMI, hypertension, hyperlipidaemia, and diabetes. No association between SBP-SD and mortality or MACCEs was found in valve surgery patients.

CONCLUSION

In-hospital day-by-day SBP variability predicts mortality and MACCEs in CABG patients, possibly representing a target during rehabilitation and treatment in secondary cardiovascular prevention.

24-hour intraocular pressure and ocular perfusion pressure in glaucoma

This review analyzes the currently available literature on circadian rhythms of intraocular pressure (IOP), blood pressure, and calculated ocular perfusion pressure (OPP) in patients with open-angle glaucoma. Although adequately powered, prospective trials are not available. The existing evidence suggests that high 24-hour IOP and OPP fluctuations can have detrimental effects in eyes with glaucoma. The currently emerging continuous IOP monitoring technologies may soon offer important contributions to the study of IOP rhythms. Once telemetric technologies become validated and widely available for clinical use, they may provide an important tool towards a better understanding of long- and short-term IOP fluctuations during a patient's daily routine. Important issues that need to be investigated further include the identification of appropriate surrogate measures of IOP and OPP fluctuation for patients unable to undergo 24-hour measurements, the determination of formulae that best describe the relationship between systemic blood pressure and IOP with OPP, and the exact clinical relevance of IOP and OPP fluctuation in individual patients. Despite the unanswered questions, a significant body of literature suggests that OPP assessment may be clinically relevant in a significant number of glaucoma patients.