Characteristics associated with responsiveness to isometric handgrip training in medicated hypertensive patients: secondary data analysis.

OBJECTIVE: Isometric handgrip training (IHT) has been shown to reduce blood pressure (BP) in hypertensive patients. However, factors that predict responsiveness to IHT are largely unknown. The aim of this study was to investigate the patient characteristics associated with the antihypertensive response to IHT using a recommended statistical approach for evaluating interindividual responses. METHODS: Data from four randomized controlled trials were joined, totaling 81 patients undergoing IHT (48.8% women; 60 ±â€Š11 years) and 90 control patients (45.6% women; 62 ±â€Š12 years). IHT consisted of 4 × 2 min isometric contractions at 30% of maximal voluntary contraction, performed three times/week for 8-12 weeks. BP was measured at baseline and following IHT and control interventions. The interindividual variation was assessed by the standard deviation of the individual responses (SDir), and linear regression analyses were conducted to explore response predictors. RESULTS: IHT significantly decreased both SBP (-5.4; 95% confidence interval (CI) -9.5 to -1.3 mmHg) and DBP (-2.8; 95% CI -5.1 to -0.6 mmHg). The interindividual variation of BP change was moderate for systolic (SDir = 5.2 mmHg, 0.30 standardized units) and low for diastolic (SDir = 1.7 mmHg, 0.15 standardized units). Sex, age, and BMI were not associated with the antihypertensive effect of IHT. However, a higher baseline SBP (b = -0.467, P < 0.001) and absence of dihydropyridine calcium channel blockers use (b = 0.340, P = 0.001) were associated with greater BP reductions. CONCLUSION: IHT reduced BP in medicated hypertensive patients regardless of age, sex, and BMI. Patients with a higher baseline SBP and those not prescribed dihydropyridine calcium channel blockers were more responsive to IHT.

Left Atrial Mechanics Following Preeclamptic Pregnancy.

BACKGROUND: Preterm preeclampsia is a pregnancy complication associated with myocardial dysfunction and premature cardiovascular disease morbidity and mortality. Left atrial (LA) strain is a noninvasive index of left ventricular end diastolic pressure and an early marker of heart failure risk. This study aimed to evaluate LA strain during the postpartum period in participants with and without preterm preeclampsia and to assess whether this varied in the presence of hypertension and/or cardiac dysfunction. METHODS: In this longitudinal cohort study, 321 women from 28 hospitals with preterm preeclampsia (cases) underwent cardiovascular assessment 6 months postpartum. This is a secondary analysis of the PHOEBE study (ISRCTN01879376). An uncomplicated pregnancy control group (n=30) was recruited from a single center for comparison. A full cross-sectional transthoracic echocardiogram was performed, and from these images, the myocardial strain of the left atrium, including reservoir, conduit, and contractile strain, as well as LA stiffness, were calculated. RESULTS: At 6 months postpartum, compared with controls, prior preeclampsia was associated with a significantly attenuated LA reservoir, conduit, and contractile strain, as well as increased LA stiffness (all P<0.001). LA strain was further reduced in preeclamptic women who had and had not developed hypertension, systolic, or diastolic dysfunction at 6 months postpartum (all P<0.05). CONCLUSIONS: LA mechanics were significantly attenuated at 6 months postpartum in participants with preterm preeclampsia, whether or not they remained hypertensive or had evidence of ventricular dysfunction. Further studies are needed to determine whether postnatal LA strain may identify women at greater risk for future cardiovascular disease.

Isometric Exercise Training and Arterial Hypertension: An Updated Review.

Hypertension is recognised as a leading attributable risk factor for cardiovascular disease and premature mortality. Global initiatives towards the prevention and treatment of arterial hypertension are centred around non-pharmacological lifestyle modification. Exercise recommendations differ between professional and scientific organisations, but are generally unanimous on the primary role of traditional aerobic and dynamic resistance exercise. In recent years, isometric exercise training (IET) has emerged as an effective novel exercise intervention with consistent evidence of reductions in blood pressure (BP) superior to that reported from traditional guideline-recommended exercise modes. Despite a wealth of emerging new data and endorsement by select governing bodies, IET remains underutilised and is not widely prescribed in clinical practice. This expert-informed review critically examines the role of IET as a potential adjuvant tool in the future clinical management of BP. We explore the efficacy, prescription protocols, evidence quality and certainty, acute cardiovascular stimulus, and physiological mechanisms underpinning its anti-hypertensive effects. We end the review with take-home suggestions regarding the direction of future IET research.

International Criteria for Reporting Study Quality for Sudden Cardiac Arrest/Death Tool.

BACKGROUND: Studies reporting on the incidence of sudden cardiac arrest and/or death (SCA/D) in athletes commonly lack methodological and reporting rigor, which has implications for screening and preventative policy in sport. To date, there are no tools designed for assessing study quality in studies investigating the incidence of SCA/D in athletes. METHODS AND RESULTS: The International Criteria for Reporting Study Quality for Sudden Cardiac Arrest/Death tool (IQ-SCA/D) was developed following a Delphi process. Sixteen international experts in sports cardiology were identified and invited. Experts voted on each domain with subsequent moderated discussion for successive rounds until consensus was reached for a final tool. Interobserver agreement between a novice, intermediate, and expert observer was then assessed from the scoring of 22 relevant studies using weighted and unweighted κ analyses. The final IQ-SCA/D tool comprises 8 domains with a summated score of a possible 22. Studies are categorized as low, intermediate, and high quality with summated IQ-SCA/D scores of ≤11, 12 to 16, and ≥17, respectively. Interrater agreement was "substantial" between all 3 observers for summated IQ-SCA/D scores and study categorization. CONCLUSIONS: The IQ-SCA/D is an expert consensus tool for assessing the study quality of research reporting the incidence of SCA/D in athletes. This tool may be used to assist researchers, reviewers, journal editors, and readers in contextualizing the methodological quality of different studies with varying athlete SCA/D incidence estimates. Importantly, the IQ-SCA/D also provides an expert-informed framework to support and guide appropriate design and reporting practices in future SCA/D incidence trials.

The implementation of a home-based isometric wall squat intervention using ratings of perceived exertion to select and control exercise intensity: a pilot study in normotensive and pre-hypertensive adults.

PURPOSE: Isometric exercise (IE) and isometric wall squat (IWS) training have been shown to be effective methods of reducing arterial blood pressure. However, most IE interventions require methodologies and equipment that could present a barrier to participation. Therefore, this study aimed to examine the effectiveness of an accessible RPE prescribed IWS intervention. METHODS: Thirty normotensive and pre-hypertensive adults were randomly assigned to a control group or one of two 4-week home-based IWS intervention groups: the first group conducted IWS exercise where intensity was prescribed and monitored using RPE (RPE-EX), whilst the other used a previously validated HR prescription method (HR-EX). Resting and ambulatory heart rate (HR) and blood pressure (BP) were measured pre- and post-intervention. RESULTS: Minimum clinically important differences (MCID; - 5 mmHg) in SBP and/or DBP were shown in 100% of intervention participants. Statistically significant reductions were shown in resting seated BP (RPE-EX: SBP: - 9 ± 6, DBP: - 6 ± 4, MAP: - 6 ± 3 mmHg; HR-EX: SBP: - 14 ± 6, DBP: - 6 ± 4, MAP: - 8 ± 4 mmHg), supine BP (RPE-EX: SBP: - 8 (- 5), DBP: - 8 (- 7), MAP: - 8 (- 4) mmHg; HR-EX: SBP: - 5 (- 4), MAP - 5 (- 4) mmHg), and ambulatory SBP (RPE-EX: - 8 ± 6 mmHg; HR-EX: - 10 ± 4 mmHg) following the interventions. There were no statistically significant differences between intervention groups in the magnitude of BP reduction. CONCLUSION: RPE prescribed IWS exercise can provide an effective and more accessible method for reducing BP at home, providing reductions comparable to the current HR-based prescription method.

Artificial intelligence calculated global longitudinal strain and left ventricular ejection fraction predicts cardiac events and all-cause mortality in patients with chest pain.

BACKGROUND: Assessment of left ventricular ejection fraction (LVEF) and myocardial deformation with global longitudinal strain (GLS) has shown promise in predicting adverse cardiovascular events. The aim of this study was to evaluate whether artificial intelligence (AI) calculated LVEF and GLS is associated with major adverse cardiac events (MACE) and all-cause mortality in patients presenting with chest pain. METHODS: We studied 296 patients presenting with chest pain, who underwent transthoracic echocardiography (TTE). Clinical data, downstream clinical investigations and patient outcomes were collected. Resting TTE images underwent AI contouring for automated calculation of LVEF and GLS with Ultromics EchoGo Core 2.0. Regression analysis was performed to identify clinical and AI calculated parameters associated with MACE and all-cause mortality. RESULTS: During a median follow-up period of 7.8 years (IQR 6.4, 8.8), MACE occurred in 34 (11.5%) patients and all-cause mortality in 60 (20%) patients. AI calculated LVEF (Odds Ratio [OR] .96; 95% CI .93-.99 and .96; 95% CI .93-.99) and GLS (1.11; 95% CI 1.01-1.21 and 1.08; 95% CI 1.00-1.16) were independently associated with MACE and all-cause mortality, respectively. According to Cox proportional hazards, a LVEF < 50% was associated with a 3.7 times MACE and 2.8 times all-cause mortality hazard rate compared to those with a LVEF ≥ 50%. Those with a GLS ≥ 15% was associated with a 2.5 times MACE and 2.3 times all-cause mortality hazard rate compared to those with a GLS ≤ 15. CONCLUSION: AI calculated resting LVEF and GLS is independently associated with MACE and all-cause mortality in high CVD risk patients. These results may have significant clinical implications through improved risk stratification of patients with chest pain, accelerated workflow of labour-intensive technical measures, and reduced healthcare costs.

Exercise training and resting blood pressure: a large-scale pairwise and network meta-analysis of randomised controlled trials.

OBJECTIVE: To perform a large-scale pairwise and network meta-analysis on the effects of all relevant exercise training modes on resting blood pressure to establish optimal antihypertensive exercise prescription practices. DESIGN: Systematic review and network meta-analysis. DATA SOURCES: PubMed (Medline), the Cochrane library and Web of Science were systematically searched. ELIGIBILITY CRITERIA: Randomised controlled trials published between 1990 and February 2023. All relevant work reporting reductions in systolic blood pressure (SBP) and/or diastolic blood pressure (DBP) following an exercise intervention of ≥2 weeks, with an eligible non-intervention control group, were included. RESULTS: 270 randomised controlled trials were ultimately included in the final analysis, with a pooled sample size of 15 827 participants. Pairwise analyses demonstrated significant reductions in resting SBP and DBP following aerobic exercise training (-4.49/-2.53 mm Hg, p<0.001), dynamic resistance training (-4.55/-3.04 mm Hg, p<0.001), combined training (-6.04/-2.54 mm Hg, p<0.001), high-intensity interval training (-4.08/-2.50 mm Hg, p<0.001) and isometric exercise training (-8.24/-4.00 mm Hg, p<0.001). As shown in the network meta-analysis, the rank order of effectiveness based on the surface under the cumulative ranking curve (SUCRA) values for SBP were isometric exercise training (SUCRA: 98.3%), combined training (75.7%), dynamic resistance training (46.1%), aerobic exercise training (40.5%) and high-intensity interval training (39.4%). Secondary network meta-analyses revealed isometric wall squat and running as the most effective submodes for reducing SBP (90.4%) and DBP (91.3%), respectively. CONCLUSION: Various exercise training modes improve resting blood pressure, particularly isometric exercise. The results of this analysis should inform future exercise guideline recommendations for the prevention and treatment of arterial hypertension.

High-Intensity Interval Training and Cardiometabolic Health in the General Population: A Systematic Review and Meta-Analysis of Randomised Controlled Trials.

BACKGROUND: High-intensity interval training (HIIT) remains a promising exercise mode in managing cardiometabolic health. Large-scale analyses are necessary to understand its magnitude of effect on important cardiometabolic risk factors and inform guideline recommendations. OBJECTIVE: We aimed to perform a novel large-scale meta-analysis on the effects of HIIT on cardiometabolic health in the general population. METHODS: PubMed (MEDLINE), the Cochrane library and Web of Science were systematically searched. Randomised controlled trials (RCTs) published between 1990 and March 2023 were eligible. Research trials reporting the effects of a HIIT intervention on at least one cardiometabolic health parameter with a non-intervention control group were considered. RESULTS: This meta-analysis included 97 RCTs with a pooled sample size of 3399 participants. HIIT produced significant improvements in 14 clinically relevant cardiometabolic health parameters, including peak aerobic capacity (VO2) [weighted mean difference (WMD): 3.895 ml min-1 kg-1, P < 0.001), left ventricular ejection fraction (WMD: 3.505%, P < 0.001), systolic (WMD: - 3.203 mmHg, P < 0.001) and diastolic (WMD: - 2.409 mmHg, P < 0.001) blood pressure, resting heart rate (WMD: - 3.902 bpm, P < 0.001) and stroke volume (WMD: 9.516 mL, P < 0.001). Body composition also significantly improved through reductions in body mass index (WMD: - 0.565 kg m-2, P < 0.001), waist circumference (WMD: - 2.843 cm, P < 0.001) and percentage body fat (WMD: - 0.972%, P < 0.001). Furthermore, there were significant reductions in fasting insulin (WMD: - 13.684 pmol L-1, P = 0.004), high-sensitivity C-reactive protein (WMD: - 0.445 mg dL-1, P = 0.043), triglycerides (WMD: - 0.090 mmol L-1, P = 0.011) and low-density lipoprotein (WMD: - 0.063 mmol L-1, P = 0.050), concurrent to a significant increase in high-density lipoprotein (WMD: 0.036 mmol L-1, P = 0.046). CONCLUSION: These results provide further support for HIIT in the clinical management of important cardiometabolic health risk factors, which may have implications for physical activity guideline recommendations.

The effect of isometric exercise training on arterial stiffness: A randomized crossover controlled study.

Isometric exercise training (IET) is an effective intervention for the management of resting blood pressure (BP). However, the effects of IET on arterial stiffness remain largely unknown. Eighteen unmedicated physically inactive participants were recruited. Participants were randomly allocated in a cross-over design to 4 weeks of home-based wall squat IET and control period, separated by a 3-week washout period. Continuous beat-to-beat hemodynamics, including early and late systolic (sBP 1 and sBP 2, respectively) and diastolic blood pressure (dBP) were recorded for a period of 5 min and waveforms were extracted and analyzed to acquire the augmentation index (AIx) as a measure of arterial stiffness. sBP 1 (-7.7 ± 12.8 mmHg, p = 0.024), sBP 2 (-5.9 ± 9.9 mmHg, p = 0.042) and dBP (-4.4 ± 7.2 mmHg, p = 0.037) all significantly decreased following IET compared to the control period. Importantly, there was a significant reduction in AIx following IET (-6.6 ± 14.5%, p = 0.02) compared to the control period. There were also adjacent significant reductions in total peripheral resistance (-140.7 ± 65.8 dynes·cm-5, p = 0.042) and pulse pressure (-3.8 ± 4.2, p = 0.003) compared to the control period. This study demonstrates an improvement in arterial stiffness following a short-term IET intervention. These findings have important clinical implications regarding cardiovascular risk. Mechanistically, these results suggest that reductions in resting BP following IET are induced via favorable vascular adaptations, although the intricate details of such adaptations are not yet clear.

Myocardial performance index as a measure of global left ventricular function improves following isometric exercise training in hypertensive patients.

As the leading cause of cardiovascular disease and mortality, hypertension remains a global health problem. Isometric exercise training (IET) has been established as efficacious in reducing resting blood pressure (BP); however, no research to date has investigated its effects on the myocardial performance index (MPI). Twenty-four unmedicated hypertensive patients were randomized to 4 weeks of IET and a control period in a crossover design. Tissue Doppler imaging was used to acquire cardiac time intervals pre- and post-IET and during the control periods. IET significantly improved all measures of cardiac time intervals, including isovolumic relaxation time (83.1 ± 10.3 vs. 76.1 ± 11.2 ms, p = 0.006), isovolumic contraction time (84.8 ± 10.3 vs. 72.8 ± 6.4 ms, p < 0.001), ejection time (304.6 ± 30.2 vs. 321.4 ± 20.8 ms, p = 0.015) and the MPI (0.56 ± 0.09 vs. 0.47 ± 0.05, p < 0.001). This is the first study to demonstrate that IET significantly improves cardiac time intervals. These findings may have important clinical implications, highlighting the potential utility of IET in the management of cardiac health in hypertensive patients.

Left ventricular assessment with artificial intelligence increases the diagnostic accuracy of stress echocardiography.

Aims: To evaluate whether left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS), automatically calculated by artificial intelligence (AI), increases the diagnostic performance of stress echocardiography (SE) for coronary artery disease (CAD) detection. Methods and results: SEs from 512 participants who underwent a clinically indicated SE (with or without contrast) for the evaluation of CAD from seven hospitals in the UK and US were studied. Visual wall motion scoring (WMS) was performed to identify inducible ischaemia. In addition, SE images at rest and stress underwent AI contouring for automated calculation of AI-LVEF and AI-GLS (apical two and four chamber images only) with Ultromics EchoGo Core 1.0. Receiver operator characteristic curves and multivariable risk models were used to assess accuracy for identification of participants subsequently found to have CAD on angiography. Participants with significant CAD were more likely to have abnormal WMS, AI-LVEF, and AI-GLS values at rest and stress (all P < 0.001). The areas under the receiver operating characteristics for WMS index, AI-LVEF, and AI-GLS at peak stress were 0.92, 0.86, and 0.82, respectively, with cut-offs of 1.12, 64%, and -17.2%, respectively. Multivariable analysis demonstrated that addition of peak AI-LVEF or peak AI-GLS to WMS significantly improved model discrimination of CAD [C-statistic (bootstrapping 2.5th, 97.5th percentile)] from 0.78 (0.69-0.87) to 0.83 (0.74-0.91) or 0.84 (0.75-0.92), respectively. Conclusion: AI calculation of LVEF and GLS by contouring of contrast-enhanced and unenhanced SEs at rest and stress is feasible and independently improves the identification of obstructive CAD beyond conventional WMSI.

One year of isometric exercise training for blood pressure management in men: a prospective randomized controlled study.

OBJECTIVE: Isometric exercise training (IET) over 4-12 weeks is an effective antihypertensive intervention. However, blood pressure (BP) reductions are reversible if exercise is not maintained. No work to date has investigated the long-term effects of IET on resting BP. METHODS: We randomized 24 unmedicated patients with high-normal BP to a 1-year wall squat IET intervention or nonintervention control group. Resting BP and various clinically important haemodynamic variables, including heart rate (HR), stroke volume (SV), cardiac output (CO) and total peripheral resistance (TPR) were measured pre and post the 1-year study period. RESULTS: One year of IET produced statistically significant reductions in resting systolic (-8.5 ±â€Š5 mmHg, P  < 0.001) and diastolic (-7.3 ±â€Š5.8 mmHg, P  < 0.001) BP compared with the control group. There was also a significant reduction in resting HR (-4.2 ±â€Š3.7 b/min, P  = 0.009) and a significant increase in SV (11.2 ±â€Š2.8 ml, P  = 0.012), with no significant change in CO (0.12 ±â€Š2.8 l/min, P  = 0.7). TPR significantly decreased following IET (-246 ±â€Š88 dyne·s/cm 5 , P  = 0.011). Adherence to the IET sessions was 77% across all participants (3x IET sessions per week), with no participant withdrawals. CONCLUSION: This novel study supports IET as an effective long-term strategy for the management of resting BP, producing clinically important, chronic BP adaptations in patients at risk of hypertension. Importantly, this work also demonstrates impressive long-term adherence rates, further supporting the implementation of IET as a means of effective BP management in clinical populations.

Exercise Training in Heart failure with Preserved and Reduced Ejection Fraction: A Systematic Review and Meta-Analysis.

BACKGROUND: While exercise training (ET) is an established tool in heart failure (HF), no research to date has analysed the efficacy of ET in both preserved (HFpEF) and reduced (HFrEF) ejection fraction phenotypes across the same clinically important parameters. METHODS: A comprehensive systematic search was performed to identify trials published between 1990 and May 2021. Controlled trials of adults reporting pre- and post-ET peak VO2, 6-min walk distance (6MWD), Minnesota Living with Heart Failure Questionnaire (MLHFQ), Kansas City Cardiomyopathy Questionnaire (KCCQ) and left ventricular ejection fraction (LVEF) were considered. Parameters of cardiac diastolic function, brain natriuretic peptides (BNP)/N-terminal prohormone of BNP (NTproBNP) and follow-up hospitalisation and mortality data were also analysed. RESULTS: Ninety-three studies (11 HFpEF and 82 HFrEF) were included in the final analysis, with a pooled sample size of 11,081 participants. HFpEF analysis demonstrated significant improvements in peak VO2 (weighted mean difference: 2.333 ml·min-1·kg-1, Pfixed < 0.001), 6MWD (WMD: 35.396 m, Pfixed < 0.001), MLHFQ (WMD: - 10.932, Prandom < 0.001), KCCQ (WMD: 3.709, Pfixed = 0.037) and E/e' (WMD: - 1.709, [95% CI] = - 2.91-0.51, Prandom = 0.005). HFrEF analysis demonstrated significant improvements in peak VO2 (WMD: 3.050 ml·min-1·kg-1, Prandom < 0.001), 6MWD (WMD: 37.299 m, Prandom < 0.001), MLHFQ (WMD: - 10.932, Prandom < 0.001), LVEF (WMD: 2.677%, Prandom = 0.002) and BNP/NTproBNP (SMD: - 1.349, Prandom < 0.001). Outcome analysis was only performed in HFrEF, which found no significant changes in hospitalisation, all-cause mortality or composite end-points. CONCLUSION: ET significantly improves exercise capacity and quality of life in both HFpEF and HFrEF patients. In HFpEF patients, ET significantly improved an important index of diastolic function, with significant improvements in LVEF and NTproBNP/BNP seen in HFrEF patients only. Such benefits did not translate into significantly reduced hospitalisation or mortality after short-term follow-up.

Valvular Heart Disease in Patients with Chronic Kidney Disease.

Valvular heart disease (VHD) is highly prevalent in patients with chronic kidney disease (CKD) from the early stages to end-stage renal disease (ESRD). Aortic and mitral valves are the most frequently affected, leading to aortic valve and/or mitral annular calcification, which, in turn, causes either valve stenosis or regurgitation at an accelerated rate compared with the general population. Tricuspid regurgitation is also prevalent in CKD and ESRD, and haemodialysis patients are at an increasingly high risk of infective endocarditis. As for pathophysiology, several mechanisms causing VHD in CKD have been proposed, highlighting the complexity of the process. Echocardiography constitutes the gold standard for the assessment of VHD in CKD/ESRD patients, despite the progress of other imaging modalities. With regard to treatment, the existing 2017 European Society of Cardiology/European Association for Cardio-Thoracic Surgery guidelines on the management of VHD addressing patients with normal kidney function are also applied to patients with CKD/ESRD.

Undiagnosed Chronic Obstructive Pulmonary Disease is Highly Prevalent in Patients Referred for Dobutamine Stress Echocardiography with Shortness of Breath.

PURPOSE: Shortness of breath (SOB) is a common symptom referral for dobutamine stress echocardiography (DSE). Patients with SOB and a normal DSE have worse long-term outcome than the general population. This suggests multiple aetiologies are involved. The purpose of this study was to assess the prevalence and clinical significance of undiagnosed COPD amongst patients referred for a DSE with SOB. METHODS: We prospectively studied 114 patients referred for DSE with SOB without prior evidence of lung disease (mean age 64.9 ± 18.5 years, 60 male). Respiratory function testing using spirometry was performed on all patients on the day of their DSE. The study end-points were cardiac events and total mortality. RESULTS: Respiratory function testing and DSE was performed in all patients and COPD was highly prevalent (n = 93). Multivariate Cox regression analysis was used to estimate the effect of dyspnoea on non-fatal cardiac events (NFCE) and all-cause mortality. Over a mean follow-up of 4.5 ± 2.6 years, the composite end-point of NFCE and all-cause mortality occurred in 62.7% and 16.7% patients, respectively. COPD (HR 1.27; 95% CI 1.17-1.93), previous myocardial infarction (HR 1.84; 95% CI 1.06-3.2), myocardial ischaemia (HR 2.56; 95% CI 1.48-4.43), peak wall motion score index (HR 4.66; 95% CI 2.26-9.6), and mitral E/E' (HR 1.21; 95% CI 1.1-1.33) were significantly associated with a NFCE. Myocardial ischaemia (HR 4.43; 95% CI 1.24-15.81) was the only independent predictor of all-cause mortality. CONCLUSION: Undiagnosed COPD is highly prevalent and independently associated with worse outcome amongst patients with SOB referred for DSE. Symptom presentation is therefore an important consideration when interpreting DSE results.

Myocardial work and left ventricular mechanical adaptations following isometric exercise training in hypertensive patients.

PURPOSE: Hypertension is a major risk factor for cardiovascular disease. Isometric exercise training (IET) reduces resting and ambulatory blood pressure; however, few studies have investigated the myocardial adaptations following IET. METHODS: We randomly assigned 24 unmedicated hypertensive patients in a cross-over study design to 4-weeks of IET and control period, separated by a 3-week washout period. Speckle tracking echocardiography was used to measure left ventricular (LV) mechanics, and global myocardial work indices were derived from non-invasive LV pressure-strain loops constructed from global longitudinal strain (GLS) indexed to brachial systolic blood pressure. RESULTS: IET significantly improved GLS (- 2.3 ± 2%, p < 0.001) and global work efficiency (2.8 ± 2%, p < 0.001), and significantly reduced global wasted work (- 42.5 ± 30 mmHg%, p < 0.001) with no significant change during the control period. CONCLUSIONS: This is the first evidence to demonstrate that IET significantly improved cardiac health in a relevant patient population. Our findings have important clinical implications for patients with high blood pressure and support the role of IET as a safe and viable therapeutic and preventative intervention in the treatment of hypertension.

Acute cardiac autonomic and haemodynamic responses to leg and arm isometric exercise.

OBJECTIVES: Acute cardiovascular responses following a single session of isometric exercise (IE) have been shown to predict chronic adaptations in blood pressure (BP) regulation. It was hypothesised that exercises which recruit more muscle mass induce greater reductions in BP compared to exercises using smaller muscle mass. To test this hypothesis, the current study aimed to compare the acute haemodynamic and autonomic responses to a single session of isometric wall squat (IWS) and isometric handgrip (IHG) training. METHODS: Twenty-six sedentary participants performed a single IWS and IHG session in a randomised cross-over design, with training composed of 4 × 2-min contractions, with 2-min rest, at 95 HRpeak and 30% MVC respectively. Haemodynamic and cardiac autonomic variables were recorded pre, during, immediately post, and 1-h post-exercise, with the change from baseline for each variable used for comparative analysis. RESULTS: During IWS exercise, there was a significantly greater increase in systolic BP (P < 0.001), diastolic BP (P < 0.001), mean BP (P < 0.001), heart rate (P < 0.001), and cardiac output (P < 0.001), and a contrasting decrease in baroreflex effectiveness index (BEI) and cardiac baroreceptor sensitivity (cBRS). In the 10-min recovery period following IWS exercise, there was a significantly greater reduction in systolic BP (P = 0.005), diastolic BP (P = 0.006), mean BP (P = 0.003), total peripheral resistance (TPR) (P < 0.001), BEI (P = 0.003), and power spectral density (PSD-RRI) (P < 0.001). There were no differences in any variables between conditions 1-h post exercise. CONCLUSIONS: Isometric wall squat exercise involving larger muscle mass is associated with a significantly greater post-exercise hypotensive response during a 10-min recovery window compared to smaller muscle mass IHG exercise. The significantly greater reduction in TPR may be an important mechanism for the differences in BP response.

Myocardial Mechanics in Hypertensive Disorders of Pregnancy: a Systematic Review and Meta-Analysis.

Global longitudinal strain (GLS) is becoming routinely used to direct the medical management of various cardiac diseases, but its application in pregnancy is unclear. Our objective was to perform a meta-analysis and pool multiple study data to consolidate the evidence base for the role of GLS in the assessment of women with hypertensive disorders of pregnancy (HDP). Electronic database searches were performed in PubMed/Medline and EMBASE for research articles reporting GLS in pregnancies complicated by HDP and normotensive pregnancies that have been published up to September 2021. The meta-analysis included 17 studies with a pooled sample size of 1723 participants, which included 951 women with HDP, of which 680 were preeclamptic, and 772 controls. The primary random-effects pooled analysis demonstrated a statistically significant weighted mean difference in GLS between the HDP and control group (mean difference: 3.08% [CI, 2.33-3.82], P<0.001). When analyzed including only preeclamptic studies, there was also a statistically significant mean difference (mean difference: 2.98% [95% CI, 1.97-3.99], P<0.001). This meta-analysis demonstrates that HDP is associated with greater cardiac maladaptation, evidenced by a significantly reduced GLS compared with normal pregnancy. Echocardiography should be considered as a screening tool in women with HDP to enable early cardiovascular risk prevention through national initiatives.

Blood pressure and cardiac autonomic adaptations to isometric exercise training: A randomized sham-controlled study.

Isometric exercise training (IET) is increasingly cited for its role in reducing resting blood pressure (BP). Despite this, few studies have investigated a potential sham effect attributing to the success of IET, thus dictating the aim of the present study. Thirty physically inactive males (n = 15) and females (n = 15) were randomly assigned into three groups. The IET group completed a wall squat intervention at 95% peak heart rate (HR) using a prescribed knee joint angle. The sham group performed a parallel intervention, but at an intensity (<75% peak HR) previously identified to be inefficacious over a 4-week training period. No-intervention controls maintained their normal daily activities. Pre- and post-measures were taken for resting and continuous blood pressure and cardiac autonomic modulation. Resting clinic and continuous beat-to-beat systolic (-15.2 ± 9.2 and -7.3 ± 5.6 mmHg), diastolic (-4.6 ± 5 and -4.5 ± 5.1), and mean (-7 ± 4.2 and -7.5 ± 5.3) BP, respectively, all significantly decreased in the IET group compared to sham and no-intervention control. The IET group observed a significant decrease in low-frequency normalized units of heart rate variability concurrent with a significant increase in high-frequency normalized units of heart rate variability compared to both the sham and no-intervention control groups. The findings of the present study reject a nonspecific effect and further support the role of IET as an effective antihypertensive intervention. Clinical Trials ID: NCT05025202.