Dundee step test: a simple method of measuring the blood pressure response to exercise

Immediate post-exercise blood pressure and arterial compliance in middle-aged and older normotensive females: A cross-sectional study

This study examined whether immediate post-exercise systolic blood pressure (SBP) is associated with arterial compliance in middle-aged and older normotensive females. A total of 548 normotensive, non-frail females aged 55 years and older with no previous history of cardiovascular disease (CVD) participated in this cross-sectional study. Large and small arterial compliance were assessed by pulse wave analysis. Reduced arterial compliance was defined based on age and sex cutoffs. SBP was measured at rest and immediately following a 3-min moderate step-test. CVD risk factors were also assessed (e.g. resting systolic and diastolic BP, fasting glucose, triglycerides, cholesterol, body mass index). A total of 15.1% and 44.0% of the participants showed reduced large and small artery compliance, respectively. Immediate post-exercise SBP was associated with reduced large (OR 1.02 per 1 mmHg increase in post-exercise SBP, 95%CI 1.01–1.04; p = 0.010) and small (OR 1.02 per 1 mmHg increase in post-exercise SBP, 95%CI 1.00–1.03; p = 0.008) arterial compliance. Participants with highest immediate post-exercise SBP (quartile 4; i.e. ≥ 165 mmHg) showed increased odds ratios for reduced large (2.67, 95%CI 1.03–6.94; p = 0.043) and small (2.27, 95%CI 1.22–4.21; p = 0.010) arterial compliance compared to those with the lowest immediate post-exercise SBP (quartile 1; i.e. ≤ 140 mmHg), independent of other established CVD risk factors. Immediate post-exercise SBP following a brief moderate step-test seems to be able to discriminate reduced arterial compliance in middle-aged and older normotensive females.

Value of myocardial work for assessment of myocardial adaptation to increased afterload in patients with high blood pressure at peak exercise

Non-invasive myocardial work (MW) indices are superior to global longitudinal strain (GLS) to assess left ventricular (LV) mechanics in situations where afterload is abnormally high. The rotational motion of the apex provides an accurate index of LV contractility. To date, there are no data about MW values during stress echocardiography (SE), particularly for the apex. Our study aims at assessing MW indices at peak exercise to better understand LV mechanics in patients with high peak systolic blood pressure (SBP). A total of 81 patients without structural or ischemic heart disease referred for SE between January and June 2019 were included. BP measurements, GLS and MW indices were performed at rest and peak exercise. In order to quantify the role of the apex, apical work fraction (AWF) was also calculated and further stratified by peak SBP. A peak SBP > 180 mmHg was considered abnormally high. There were 36 (44%) patients who had peak SBP > 180 mmHg. They showed similar resting GLS and MW values when compared to control. However, peak stress global work index, constructive work and wasted work (GWW) increased significantly (P-value < 0.05), with a relatively constant global work efficiency. In the multivariate analysis, peak SBP > 180 mmHg was associated with threefold increased odds of abnormal peak GWW > 96.5 mmHg% (median value) (odds ratio 3.0, P-value 0.003). Apical work increased significantly when stratified by peak SBP (P-value 0.003) and AWF increased from 33 ± 3% to 37 ± 3% (rest-stress), P-value < 0.0001, but remained constant when stratified by peak SBP. Our analysis provides new data on MW indices at peak stress, particularly for patients with abnormal peak SBP response, and supports the role and the contribution of the apex to MW.

Protocol for the HAPPY Hearts study: cardiovascular screening for the early detection of future adverse cardiovascular outcomes in middle-aged and older women: a prospective, observational cohort study

INTRODUCTION

Efforts to identify individuals at a higher risk for adverse cardiovascular outcomes focus on traditional risk factors, such as age, sex, smoking status, blood pressure and and cholesterol; however, this approach does not directly assess cardiovascular function and may underestimate the risk of experiencing adverse cardiovascular outcomes in women. This prospective, observational cohort study will examine the ability of the Heart Attack Prevention Program for You (HAPPY) Hearts screening protocol, a series of non-invasive procedures to identify middle-aged and older women who are at an elevated risk for experiencing an adverse cardiovascular event in the 5-year period after screening. The predictive value of the HAPPY Hearts protocol will also be compared with the Framingham Risk Score to determine the sensitivity for estimating risk for an adverse cardiovascular outcome.

METHODS AND ANALYSIS

One thousand women 55 years of age or older will be recruited to be screened by the HAPPY Hearts protocol. This involves the cardiovascular assessment of resting blood pressure, blood pressure response to 3 min of moderate intensity exercise and large and small arterial elasticity. The participants will be classified into risk categories based on these measures. The incidence of the following adverse cardiovascular outcomes will be assessed in the 5-year period after screening in both groups: ischaemic heart disease, acute myocardial infarction, stroke, percutaneous coronary intervention, coronary bypass surgery, congestive heart failure and new hypertension.

ETHICS AND DISSEMINATION

Information gathered in this research will be published in peer-reviewed journals and presented in a programme evaluation report to inform Manitoba Health and key stakeholders about the outcomes of the study. The University of Manitoba Health Research Ethics Board has approved the study protocol V.2.0, dated 29 September 2014 (H2014:224).

TRIAL REGISTRATION NUMBER

NCT02863211.

Exaggerated Exercise Blood Pressure Response and Future Cardiovascular Disease

Exaggerated blood pressure (BP) response to exercise predicts future hypertension. However, there is considerable lack of understanding regarding the mechanism of how this abnormal response is generated, and how it relates to the future establishment of cardiovascular disease. The authors studied 82 healthy male volunteers without cardiovascular risk factors. The participants were categorized into two age-matched groups depending on their exercise systolic BP (ExSBP) rise after 3 minutes of exercise using a submaximal step test: exaggerated ExSBP group (hyper-responders [peak SBP ≥ 180 mm Hg]) and low ExSBP responder group (hypo-responders [peak SBP <180 mm Hg]). Forearm venous occlusion plethysmography and intra-arterial infusions of acetylcholine (ACh), N(G)-monomethyl-L-arginine (L-NMMA), sodium nitroprusside (SNP), and norepinephrine (NE) were used to assess vascular reactivity. Proximal aortic compliance was assessed with ultrasound, and neurohormonal blood sampling was performed at rest and during peak exercise. The hyper-responder group exhibited a significantly lower increase in forearm blood flow (FBF) with ACh compared with the hypo-responder group (ΔFBF 215% [14] vs 332.3% [28], mean [standard error of the mean]; P<.001), as well as decreased proximal aortic compliance. The vasoconstrictive response to L-NMMA was significantly impaired in the hyper-responder group in comparison to the hypo-responder group (ΔFBF -40.2% [1.6] vs -50.2% [2.6]; P<.05). In contrast, the vascular response to SNP and NE were comparable in both groups. Peak exercise plasma angiotensin II levels were significantly higher in the hyper-responder group (31 [1] vs 23 [2] pg/mL, P=.01). An exaggerated BP response to exercise is related to endothelial dysfunction, decreased proximal aortic compliance, and increased exercise-related neurohormonal activation, the constellation of which may explain future cardiovascular disease.

South Asians have elevated postexercise blood pressure and myocardial oxygen consumption compared to Europeans despite equivalent resting pressure

Background

Stroke mortality rate is higher in South Asians than in Europeans, despite equivalent or lower resting blood pressure (BP). Elevated recovery BP after exercise predicts stroke, independently of resting values. We hypothesized that South Asians would have adverse postexercise hemodynamics and sought explanations for this.

Methods and Results

A population-based sample of 147 European and 145 South Asian middle-aged men and women performed the Dundee 3-minute step test. Cardiovascular risk factors were measured. BP, heart rate, and rate–pressure product, a measure of myocardial oxygen consumption, were compared. With 90% power and 5% significance, we could detect a difference of 0.38 of a standard deviation in any outcome measure. Resting systolic BP was similar in South Asians (144 mm Hg) and Europeans (142 mm Hg) (P=0.2), as was exercise BP (P=0.4). However, recovery systolic BP at 3 minutes after exercise was higher in South Asians by 4.3 mm Hg (95% confidence interval [CI], 0.2 to 8.3 mm Hg; P=0.04). This effect persisted when adjusted for exercise BP and work effort (5.4 mm Hg [95% CI, 2.2 to 8.7 mm Hg; P=0.001]). Adjustment for baroreflex insensitivity and greater aortic stiffness in South Asians contributes greatly to attenuating this ethnic difference (1.9 mm Hg [95% CI, −0.9 to 4.6 mm Hg; P=0.4]). Similarly, rate–pressure product recovery after exercise was impaired in South Asians by 735 mm Hg/min (95% CI, 137 to 1334 mm Hg/min; P=0.02); again, adjustment for baroreflex insensitivity and aortic stiffness attenuated this difference (261 mm Hg/min [95% CI, −39 to 561 mm Hg/min; P=0.3]).

Conclusion

Postexercise recovery of BP and rate–pressure product is impaired in South Asians compared to Europeans even though resting and exercise BP are similar. This is associated with the autonomic dysfunction and aortic stiffness in South Asians. (J Am Heart Assoc. 2012;1:e000281 doi: 10.1161/JAHA.111.000281.)

Exercise and energy intake in overweight, sedentary individuals

Exercise expends energy, but without dietary intervention, exercise does not appear to produce substantial weight loss. The present study examined whether overweight, sedentary individuals increase their energy intake after moderate intensity exercise, particularly in the presence of negative mood. A repeated measures design was used where overweight, sedentary individuals (N=65) completed, in counterbalanced order, two conditions: 3 min of exercise (Active) and 3 min of sedentary activity (Sedentary) during one session. Snack foods were presented 10 min after each activity. Mixed-effects regression modeling revealed no significant effect of Active versus Sedentary condition on energy intake. However, moderational analyses revealed that change in negative mood interacted with condition to predict energy intake, such that participants who reported increased negative mood during exercise consumed more calories in the Active compared to the Sedentary condition. That a short bout of exercise resulted in mood deterioration and increased energy intake for some overweight, sedentary individuals is concerning. Further research examining behavioral and physiological mechanisms of mood deterioration and caloric overcompensation following exercise in overweight, sedentary individuals is warranted.

What is the role of angiotensin-receptor blockade in cardiovascular protection?

The role of angiotensin II, the key mediator of the renin-angiotensin-aldosterone system, in the pathophysiology of cardiovascular disease is well known. Pharmacologic interruption of the activity of angiotensin II, either through blockade of the angiotensin receptor or inhibition of angiotensin-converting enzyme, is associated with a reduction in cardiovascular disease morbidity and mortality, as evidenced by accumulated data from large-scale, well-controlled clinical trials in high-risk populations. As the underlying mechanisms of vascular disease and the effects of blockade of the renin-angiotensin-aldosterone system on these processes have been further defined, the therapeutic focus has begun to shift toward prevention of disease progression at earlier stages. Continued research has identified early signs of vascular disease, such as endothelial dysfunction and vascular and cardiac remodeling, which occur long before clinical manifestations of cardiovascular disease become evident. Diagnostic tests are now available to assess otherwise healthy individuals for these signs. A preliminary trial is under way to evaluate the role of angiotensin receptor blockade as preventive treatment of individuals with early signs of vascular or cardiac disease.

Screening for early detection of cardiovascular disease in asymptomatic individuals

OBJECTIVE

Primary prevention of cardiovascular disease has been aimed at risk factor identification and treatment without efforts to document early cardiovascular disease. The objective of the current study is to screen individuals with vascular and cardiac tests aimed at identifying early abnormalities likely to progress and to measure risk contributors susceptible to therapy.

METHODS

A center was established for comprehensive screening of an asymptomatic population with 10 tests designed to detect early vascular and cardiac abnormalities and blood tests to identify potential targets for risk contributor intervention. The first 396 individuals screened in the center have been analyzed.

RESULTS

Using a scoring system from 0 (no disease) to 20 (advanced disease), 49% of the population exhibited scores of > or =5 and 39% exhibited scores of > or =6. These scores appear indicative of early disease mandating initiation of or change in medical therapy, which was recommended to the individuals screened and to their primary care physicians.

CONCLUSION

The screening tests utilized are effective in uncovering unsuspected early cardiovascular disease in which targeted treatment could be effective in reducing the incidence of cardiovascular events in susceptible individuals. Documentation of the sensitivity and specificity of this approach requires longitudinal study.