Office blood pressure underestimates ambulatory blood pressure in peripheral arterial disease in comparison to healthy controls

Walking Training Improves Ambulatory Blood Pressure Variability in Claudication

Fundamento:

O treinamento de caminhada (TC) melhora a capacidade de caminhar e reduz a pressão arterial (PA) clínica em pacientes com doença arterial periférica (DAP), mas seus efeitos na PA ambulatorial permanecem desconhecidos.

Objetivo:

Investigar o efeito de 12 semanas de TC na PA ambulatorial e sua variabilidade em pacientes com DAP.

Métodos:

Trinta e cinco pacientes do sexo masculino com DAP e sintomas de claudicação foram alocados aleatoriamente em dois grupos: controle (n = 16, 30 min de alongamento) e TC (n = 19, 15 séries de 2 minutos de caminhada na frequência cardíaca em que ocorreu limiar de dor intercalados por 2 minutos de repouso em pé). Antes e depois de 12 semanas, a PA ambulatorial de 24 horas foi avaliada. Os índices de variabilidade da PA ambulatorial avaliados em ambos os momentos incluíram o desvio-padrão de 24 horas (DP₂₄), o desvio-padrão ponderado de vigília e sono (DP_vs) e a variabilidade real média de 24 horas (VRM₂₄). Os dados foram analisados por ANOVAs mistas de dois fatores, considerando significativo P<0,05.

Resultados:

Após 12 semanas, nenhum dos grupos apresentou alterações na PA de 24 horas, vigília e sono. O TC diminuiu as variabilidades da PA sistólica e média (PA sistólica – 13,3 ± 2,8 vs 11,8 ± 2,3; 12,1 ± 2,84 vs 10,7 ± 2,5; e 9,4 ± 2,3 vs 8,8 ± 2,2 mmHg; PA média – 11,0 ± 1,7 vs 10,4 ± 1,9; 10,1 ± 1,6 vs 9,1 ± 1,7; e 8,0 ± 1,7 vs 7,2 ± 1,5 mmHg para DP₂₄, DPvs e VRM₂₄, respectivamente). Nenhum dos grupos apresentou mudanças significantesnos índices de variabilidade da PA diastólica após 12 semanas.

Conclusões:

O TC não altera os níveis ambulatoriais da PA, mas diminui a sua variabilidade em pacientes com DAP. Essa melhora pode ter um impacto favorável no risco cardiovascular de pacientes com DAP sintomática. (Arq Bras Cardiol. 2021; 116(5):898-905)

Ambulatory blood pressure monitoring and blood pressure control in patients with coronary artery disease-A randomized controlled trial

Office blood pressure (OBP) is used for diagnosing and treating hypertension but ambulatory blood pressure measurement (ABPM) associates more accurately with patient outcome. BP control is important in secondary prevention but it is unknown whether the use of APBM improves BP-control in this setting. Our objective was to investigate whether physician awareness of ABP after percutaneous coronary intervention (PCI) improved BP-control. Methods: A total of 200 patients performed ABPM before and after their PCI follow-up visit. Patients were randomized to open (O) or concealed (C) ABPM results for the physician at the follow-up visit. The change in ABP and antihypertensive medication in relation to baseline ABP was compared between the two groups. Results: The average OBP (O and C: 128/76 mmHg) and ABP (O: 123/73 mmHg, C: 127/74 mmHg) was well controlled and did not change between the first and second measurement. A slight increase in systolic ABP during night time was observed in the open arm compared to the concealed arm. Among patients with high ABP (>130/80 mm Hg) at baseline more patients in the C compared to O group remained with a high ABP at the end of study 34/44 (77%) vs 19/34 (56%), p = 0.045. There was a positive correlation between baseline systolic ABP and ABP change in both the O (r = 0.41, p < 0.001) and the C (r = 0.24, p = 0.014) groups but the association was steeper in the open group (p = 0.035). In patients with low ABP an increase and in patients with high ABP a decrease in ABP was observed in the O group where more changes in medication were done. Conclusions: ABPM did not lower blood pressure in patients with CAD apart from in those with elevated ABP but led to more relevant changes in antihypertensive treatments. Further studies are needed to answer whether patient outcome is affected.

Relationship between walking capacity and ambulatory blood pressure in patients with intermittent claudication

OBJECTIVE

Patients with intermittent claudication (IC) often have high blood pressure (BP), which increases their cardiovascular risk. However, whether walking capacity is associated with BP levels in patients with IC remains unknown. Therefore, this study was designed to investigate whether the total walking distance is associated with ambulatory BP in patients with IC.

PARTICIPANTS AND METHODS

This was a cross-sectional study of 75 patients with IC (58 men; 17 women). A maximal treadmill test (Gardner protocol) was performed to assess total walking distance in these patients. Furthermore, ambulatory BP, heart rate, rate-pressure product, and BP load were obtained over a 24-h period. One-way analysis of variance and multiple linear regression were carried out.

RESULTS

Walking capacity was correlated negatively with the following: (i) asleep systolic BP, diastolic BP, mean BP and heart rate; (ii) 24-h, awake and asleep RPP; and (iii) awake and asleep systolic BP load (all P<0.05). These associations occurred irrespective of confounders such as age, sex, BMI, smoking status, and number of antihypertensive medications.

CONCLUSION

A better walking capacity is associated with lower ambulatory BP parameters in patients with IC.

Amlodipine+benazepril is superior to hydrochlorothiazide+benazepril irrespective of baseline pulse pressure: subanalysis of the ACCOMPLISH trial

Pulse pressure (PP) is an independent risk factor for cardiovascular (CV) disease and death but few studies have investigated the effect of antihypertensive treatments in relation to PP levels before treatment. The Avoiding Cardiovascular Events Through Combination Therapy in Patients Living With Systolic Hypertension (ACCOMPLISH) trial showed that the combination of benazepril+amlodipine (B+A) is superior to benazepril+hydrochlorothiazide (B+H) in reducing CV events. We aimed to investigate whether the treatment effects in the ACCOMPLISH trial were dependent on baseline PP. High-risk hypertensive patients (n=11,499) were randomized to double-blinded treatment with single-pill combinations of either B+A or B+H and followed for 36 months. Patients were divided into tertiles according to their baseline PP and events (CV mortality/myocardial infarction or stroke) were compared. Hazard ratios (HRs) for the treatment effect (B+A over B+H) were calculated in a Cox regression model with age, coronary artery disease, and diabetes mellitus as covariates and were compared across the tertiles. The event rate was increased in the high tertile of PP compared with the low tertile (7.2% vs 4.4% P<.01). In the high and medium PP tertiles, HRs were 0.75 (95% confidence interval [CI], 0.60-0.95; P=.018) and 0.74 (CI, 0.56-0.98, P=.034), respectively, in favor of B+A. There was no significant difference between the treatments in the low tertile and no significant differences in treatment effect when comparing the HRs between tertiles of PP. B+A has superior CV protection over B+H in high-risk hypertensive patients independent of baseline PP although the absolute treatment effect is enhanced in the higher tertiles of PP where event rates are higher.

Sildenafil improves skeletal muscle oxygenation during exercise in men with intermittent claudication

Endothelial dysfunction caused by defective nitric oxide (NO) signaling plays a pivotal role in the pathogenesis of intermittent claudication (IC). In the present study, we evaluated the acute effects of sildenafil, a phosphodiesterase type 5 inhibitor that acts by prolonging NO-mediated cGMP signaling in vascular smooth muscle, on blood pressure (BP), skeletal muscle oxygenation, and walking tolerance in patients with IC. A randomized, double-blind, crossover study was conducted in which 12 men with stable IC received two consecutive doses of 50 mg of sildenafil or matching placebo and underwent a symptom-limited exercise test on the treadmill. Changes in gastrocnemius deoxy-hemoglobin by near-infrared spectroscopy estimated peripheral muscle O2delivery-to-utilization matching. Systolic BP was significantly lower during the sildenafil trial relative to placebo during supine rest (∼15 mmHg), submaximal exercise (∼14 mmHg), and throughout recovery (∼18 mmHg) ( P < 0.05). Diastolic BP was also lower after sildenafil during upright rest (∼6 mmHg) and during recovery from exercise (∼7 mmHg) ( P < 0.05). Gastrocnemius deoxygenation was consistently reduced during submaximal exercise (∼41%) and at peak exercise (∼34%) following sildenafil compared with placebo ( P < 0.05). However, pain-free walking time (placebo: 335 ± 42 s vs. sildenafil: 294 ± 35 s) and maximal walking time (placebo: 701 ± 58 s vs. sildenafil: 716 ± 62 s) did not differ between trials. Acute administration of sildenafil lowers BP and improves skeletal muscle oxygenation during exercise but does not enhance walking tolerance in patients with IC. Whether the beneficial effects of sildenafil on muscle oxygenation can be sustained over time and translated into positive clinical outcomes deserve further consideration in this patient population.

Ambulatory pulse pressure predicts cardiovascular events in patients with peripheral arterial disease

BACKGROUND

Patients with peripheral arterial disease (PAD) are at high risk of cardiovascular (CV) events and often have hypertension with a high pulse pressure (PP). We studied the prognostic value of ambulatory blood pressure (ABP) in PAD patients with special reference to PP.

METHODS

98 consecutive males with PAD had 24-h ABP measurements. The mean age was 68 years and CV comorbidity was prevalent. The outcome variable was CV events defined as CV mortality or any hospitalization for myocardial infarction, stroke or coronary revascularization. The predictive value of ABP variables was assessed by Cox regression. 90 age-matched men free of CV disease served as controls.

RESULTS

During follow-up (median 71 months), 36 patients and seven controls had at least one CV event. In PAD patients, 24-h PP (hazard ratios, HR, 1.48 (95% confidence interval, CI, 1.14-1.92), p <0.01) predicted CV events. Office PP did not predict events in PAD patients (HR 1.15 (0.97-1.38), ns). In multivariate analysis, 24-h PP (HR 1.48 (1.12-1.95), p <0.01) remained a predictor of CV events.

CONCLUSIONS

Ambulatory PP predicts CV events in patients with PAD. ABP measurement may be indicated for better risk stratification in PAD patients.

Myocardial ischaemia in patients with peripheral arterial disease

AIM

To study the relation between myocardial ischemia assessed with different techniques in patients with peripheral arterial disease (PAD) in comparison with a matched control group.

METHODS

Ninety-nine male patients with PAD and 94 age- and sex-matched control subjects without PAD or ischaemic heart disease performed a exercise treadmill test, dipyridamole Tc-99m sestamibi myocardial perfusion SPECT (MPS) (43 controls) and 48-h ambulatory ECG (AECG)-monitoring (43 controls).

RESULTS

Thirteen of 99 patients had irreversible and 24 of 99 had reversible perfusion defects in MPS in comparison with 0 of 43 and six of 43 of control subjects respectively (P<0.01). Thirteen of 84 evaluable patients experienced a total of 36 episodes of ST-depression in AECG in comparison with two episodes in two of 42 control subjects (P = 0.07). Out of 13 patients with ST-depression episodes only three had reversible ischaemia in MPS.

CONCLUSION

Most PAD patients with episodes of ST-segment depression have no reversible ischaemia as assessed with dipyridamole-stress MPS. Episodes of ST-segment depression may reflect types of myocardial ischaemia that are different from those detected by MPS.

Plasma NT-proBNP concentration is related to ambulatory pulse pressure in peripheral arterial disease

BACKGROUND

Increased levels of N-terminal prohormone brain natriuretic peptide (NT-proBNP) are associated with left ventricular dysfunction (LVD) and left ventricular hypertrophy (LVH), but the relation of NT-proBNP to ambulatory blood pressure (ABP) and hypertensive target organ damage in high-risk patients with peripheral arterial disease (PAD) has not been studied. We hypothesized that NT-proBNP levels were increased in patients with PAD in comparison to a matched control group and that levels of NT-proBNP were related to ABP.

METHODS

Blood samples were analysed for NT-proBNP in 103 males with PAD and 96 age- and sex-matched controls. Ninety-eight PAD patients performed ABP monitoring and 99 underwent Tc-99m Sestamibi myocardial perfusion SPECT.

RESULTS

NT-proBNP was significantly increased in PAD patients compared with controls [median (interquartiles)] 167(76, 418) vs 68(38, 142) pg/ml, p<0.001. Plasma levels of NT-proBNP correlated positively to systolic blood pressure (SBP), pulse pressure (PP), night-day ratio of SBP and showed the strongest correlation to average night PP (r=0.42, p<0.001). In multiple regression analysis, night PP remained independently related to NT-proBNP.

CONCLUSION

NT-proBNP levels are markedly increased in PAD patients compared to age-matched controls. Night PP is related to NT-proBNP levels independently of other variables highlighting the importance of ambulatory PP as a cardiovascular risk factor. Measurement of NT-proBNP could be indicated in PAD patients for further risk stratification.