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Aims: Controversy remains as to whether the exercise stress test (EST) is sufficient for risk evaluation in patients with pre-excitation. This study aims to clarify the usefulness of EST in risk stratification in both asymptomatic and symptomatic patients presenting with pre-excitation., Methods and Results: This prospective study includes consecutive asymptomatic and symptomatic patients with pre-excitation referred for risk assessment. All participants performed an incremental EST (bicycle) prior to an electrophysiology study (EPS). Primary data from the EST included loss of pre-excitation during exercise, and primary data from the EPS included the measurement of accessory pathway effective refractory period (APERP), shortest pre-excited RR interval (SPERRI), and inducible arrhythmia with the use of a beta-adrenergic receptor agonist if deemed necessary. One hundred and sixty-four patients (59 asymptomatic, 105 symptomatic) completed an EST and EPS. Forty-five patients (27%) demonstrated low-risk findings on EST, of which 19 were asymptomatic and 26 were symptomatic. Six patients with low-risk EST findings had SPERRI/APERP ≤ 250 ms at EPS, and two of them were asymptomatic. The sensitivity, specificity, positive predictive value, negative predictive value (NPV), and accuracy of low-risk EST for excluding patients with SPERRI/APERP ≤ 250 ms were 40, 91, 87, 51, and 60%, respectively. The number of patients with inducible arrhythmia at EPS was similar in the asymptomatic (36, 69%) and symptomatic (73, 61%) groups., Conclusion: Sudden loss of pre-excitation during EST has a low NPV in excluding high-risk APs. The EPS with the use of isoproterenol should be considered to accurately assess the risk of patients with pre-excitation regardless of symptoms (ClinicalTrials.gov Identifier: NCT03301935)., Competing Interests: Conflict of interest: M.J.-U. is a consultant for Johnson & Johnson and Medtronic and has received research grants from Medtronic. N.D. and A.P.N. have received speaker fees from Johnson & Johnson. F.Å. is a consultant for Johnson & Johnson and Abbott. F.B. reports fees from committee work in trials sponsored by Medtronic and Biotronik. Industry-related activities as chair or speaker have been organized through F.B.’s employer with no payment being directly transferred to F.B. E.S. has received institutional consulting fees from lecture fees from Bayer, Bristol-Myers Squibb-Pfizer, Boehringer Ingelheim, Johnson & Johnson, and Merck Sharp & Dohme. All remaining authors have declared no conflicts of interest., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Although long-QT syndrome (LQTS) with a normal range QT interval at rest leads to fatal ventricular arrhythmias, it is difficult to diagnose. In this article, we present a rare case of a patient who suffered a cardiac arrest and was recently diagnosed with LQTS and coronary vasospasm. A 62-year-old man with no syncopal episodes had a cardiopulmonary arrest while running. During coronary angiography, vasospasm was induced and we prescribed coronary vasodilators, including calcium channel blockers. An exercise stress test was performed to evaluate the effect of medications and accidentally unveiled exercise-induced QT prolongation. He was diagnosed with LQTS based on diagnostic criteria. Pharmacotherapy and an implantable cardioverter defibrillator were used for his medical management. It is extremely rare for LQTS and coronary vasospasm to coexist. In cases of exercise-induced arrhythmic events, the exercise stress test might be helpful to diagnose underlying disease.

Aim: This study was designed to examine the associations between an exaggerated systolic blood pressure (SBP) response to exercise and the nutrient intake in normotensive subjects. Methods: The subjects consisted of 302 normotensive subjects (64 males and 238 females; age, 48.4 ± 11.3 years) without a history of cardiovascular disease or stroke who were not taking any medications. Each subject performed a multistage graded submaximal exercise stress test using an electric bicycle ergometer, and their blood pressure was measured at rest and during the last minute of each stage. The nutrient intake was assessed using a self-administered food frequency questionnaire. An exaggerated SBP response to exercise was defined according to the criteria of the Framingham Study (peak SBP ≥210 mmHg in males, or ≥190 mmHg in females). Results: An exaggerated SBP response to exercise was observed in 85 subjects. A multiple logistic regression analysis revealed that the dietary sodium-to-potassium (Na/K) ratio (odds ratio [OR]: 5.75, 95% confidence interval [CI]: 2.37-13.75, p = 0.001) and vitamin E intake (OR: 0.67, 95% CI: 0.51-0.93, p = 0.012) were significantly associated with an exaggerated SBP response to exercise. Furthermore, the percent change in SBP during exercise was found to be significantly associated with an increase in the dietary Na/K ratio (p for trend = 0.0005) and a decrease in the vitamin E intake (p for trend = 0.018). Conclusions: These results suggest that an exaggerated SBP response to exercise was associated with the dietary sodium, potassium, and antioxidant vitamin intake in normotensive subjects. [ABSTRACT FROM AUTHOR]

Exercise stress testing can have a central role in the assessment of cardiovascular disease. Contemporary data, however, has highlighted the added value of imaging modalities over the exercise electrocardiogram in the investigation of coronary artery disease. Given the physiological changes associated with exercise and the possibility to address other parameters such as rhythm changes and the chronotropic response, exercise stress testing with continuous electrocardiographic monitoring can still have an important place in contemporary clinical practice. We report the case of a complete atrioventricular block associated with exercise and discuss the current role of exercise stress testing with continuous electrocardiographic monitoring in this entity. [ABSTRACT FROM AUTHOR]

Résumé L'épreuve d'effort fait-elle encore partie des examens utiles dans la détection des cardiopathies à risque chez des sujets sportifs ? Doit-on continuer à l'utiliser comme examen de surveillance chez des patients sportifs coronariens ? Les méta-analyses, considérant un sous-décalage ST de plus de 1 mm comme critère de positivité, soulignent la faible prévalence d'examens anormaux et un taux important de faux-positifs. Mais pour le diagnostic de la maladie coronaire, ce sont surtout l'évolution du segment ST à l'effort ou en récupération et la survenue d'arythmies à l'effort qui permettent de détecter les vrais positifs. Lorsque le risque coronarien est plus important (présence de facteurs de risque, reprise du sport, efforts intenses et prolongés), il paraît licite de recommander un tel examen de manière régulière chez les hommes de plus de 40 ans avec deux facteurs de risque mais également chez les vétérans reprenant le sport après une période d'inactivité prolongée. Pour le sportif coronarien asymptomatique l'épreuve d'effort reste au centre de la décision finale d'autorisation de reprise d'un sport en compétition quelle que soit le mode de revascularisation. Bien sûr l'épreuve d'effort, même incontournable reste imparfaite dans le dépistage d'une coronaropathie chez le sportif asymptomatique. Elle apporte cependant d'autres renseignements à la condition d'être maximale, et d'attacher de l'importance aux arythmies, au profil tensionnel et à la puissance maximale développée en complément de la seule étude du segment ST. Abstract Is the stress test still part of the useful examinations in the detection of risk heart disease in sports subjects? Should we continue to use it as a surveillance examination in coronary sports patients? Meta-analysis, considering a ST subshift of more than 1 mm as a criterion for positivity, underline the low prevalence of abnormal examinations and a significant rate of false-positives. But for the diagnosis of coronary artery disease, it is mainly the evolution of the ST segment to effort or recovery and the occurrence of stress arrhythmias that detect true positivity. When coronary risk is more important (presence of risk factors, resumption of sport, intense and prolonged efforts), it seems lawful to recommend such a review on a regular basis among men over 40 years of age with two risk factors but Also among veterans taking up sport after a period of prolonged inactivity. For the asymptomatic coronary athlete the stress test remains at the centre of the final decision for the resumption of a sport in competition irrespective of the method of revascularization. Of course the stress test, even inevitable, remains flawed in the detection of coronary artery disease in the asymptomatic athlete. However, it provides additional information on the condition of being maximal, and attaching importance to arrhythmias, the tensional profile and the maximum power developed in addition to the ST segment's only study. [ABSTRACT FROM AUTHOR]

Aims To evaluate the impact of diabetes mellitus (DM) on the accuracy of myocardial perfusion scintigraphy (MPS) in detecting coronary artery disease (CAD). Methods and results Two hundred and sixteen patients with DM and 432 matched controls were submitted to MPS on a dedicated cardiac camera equipped with cadmium–zinc–telluride (CZT) detectors and coronary angiography. Exercise stress was performed in 442 (68%) patients, while the remainders underwent vasodilator stress. Exercise level was determined as the percentage of the predicted maximal workload that was attained (%Wattmax). The summed difference score was derived from CZT images. A coronary stenosis >70% was considered obstructive. The prevalence of obstructive CAD was 59.7% in patients with DM and 56.2% in controls (P  = NS). The accuracy of MPS in detecting CAD was similar in patients with and without DM [area under the ROC curve (AUC) 0.77 vs. 0.78, P  = NS]. An interaction between the accuracy of MPS and cardiac stress-protocol was revealed. In fact, in patients with DM exercise stress CZT had a lower accuracy than vasodilator-stress (AUC 0.70 vs. 0.89, P  < 0.001), because of a lower specificity (45% vs. 69%), while in the control group the accuracy of MPS was similar regardless of the stress-protocol adopted. Patients with DM attained a significantly lower %Wattmax during exercise than controls (76 ± 27% vs. 82 ± 26%, P  = 0.038), which resulted an independent predictor of reduced specificity (P  = 0.026). Conclusion The accuracy of CZT imaging in patients with DM is elevated, and it is quite comparable to the one obtained in patients without DM. However, a reduced specificity can be expected in the case of exercise stress CZT, because of an impaired exercise capacity. [ABSTRACT FROM AUTHOR]

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Primary aldosteronism (PA) is associated with objectively measured lower physical fitness and blunted response of the renin-angiotensin-aldosterone system to exercise. The purpose of this pilot study was to objectively measure exercise response of the renin-angiotensin-aldosterone system and cardiopulmonary fitness changes after laparoscopic adrenalectomy (ADE) in patients with unilateral PA. We examined a total of 14 patients with confirmed PA before and after ADE, by means of spiroergometry and hormonal evaluation. As expected, after adrenalectomy basal aldosterone (Aldo) levels before exercise decreased significantly, with a concomitant increase in plasma renin (PR). The increase in Aldo (285.9±171.3 to 434.1± 278.2 ng/l; p=0.02) and blunted increase in PR (7.1±0.4 to 8.9±10.4 pg/ml; NS) post-exercise before ADE became significant after ADE Aldo post-ADE (46.8±18.8 to 106.5± 68.1 ng/l; p<0.0001) and PR post-ADE (20.1±14.5 to 33.9± 30.7 pg/ml; p=0.014). After adrenalectomy, the patients had a non-significant increase in peak workload and VO2peak. We found normalization of the renin-angiotensin-aldosterone system response to exercise with little changes in cardiopulmonary fitness six months after ADE. [ABSTRACT FROM AUTHOR]

Heart rate variability (HRV) analysis during exercise is an interesting noninvasive tool to measure the cardiovascular response to the stress of exercise. Wearable heart rate monitors are a comfortable option to measure interbeat (RR) intervals while doing physical activities. It is necessary to evaluate the agreement between HRV parameters derived from the RR series recorded by wearable devices and those derived from an electrocardiogram (ECG) during dynamic exercise of low to high intensity. Twenty-three male volunteers performed an exercise stress test on a cycle ergometer. Subjects wore a Polar RS800 device, whereas ECG was also recorded simultaneously to extract the reference RR intervals. A time-frequency spectral analysis was performed to extract the instantaneous mean heart rate (HRM), and the power of low-frequency (PLF) and high-frequency (PHF) components, the latter centered on the respiratory frequency. Analysis was done in intervals of different exercise intensity based on oxygen consumption. Linear correlation, reliability, and agreement were computed in each interval. The agreement between the RR series obtained from the Polar device and from the ECG is high throughout the whole test although the shorter the RR is, the more differences there are. Both methods are interchangeable when analyzing HRV at rest. At high exercise intensity, HRM and PLF still presented a high correlation (ρ > 0.8) and excellent reliability and agreement indices (above 0.9). However, the PHF measurements from the Polar showed reliability and agreement coefficients around 0.5 or lower when the level of the exercise increases (for levels of O2 above 60%). [ABSTRACT FROM AUTHOR]

Background: Diabetes mellitus (DM) is among the most common chronic diseases in the world, affecting about 180 million people in 2008, and the number is expected to be doubled by 2030 There are as many as 12.5 million diabetic patients with silent coronary artery disease. Aim: The aim of this study was to assess the incidence and extent of coronary artery disease among diabetic patients with occult CHD. Methods: A comparative study of asymptomatic diabetic patients and control group for evidence of CAD was conducted over the period from May 2012 to November 2013. The studied population includes a total of 82 diabetic patients and 82 healthy persons as a control group. Both diabetic and control groups underwent exercise stress test by treadmill, and coronary angiography was done to patients with positive test. Results: There was highly significant association (P

Background: Cardiac rehabilitation improves functional capacity in cardiac patients after coronary artery bypass. The aim of this study was to compare the eight weeks of interval training with continuous training on stress test physiological variables in patient with cardiac diseases after coronary artery bypass graft (CABG) surgery . Methods: In this clinical trial study, 30 patient with cardiac diseases in Tehran Heart Center (Iran) having had CABG surgery were randomly divided into two groups, high-intensity interval and continuous moderate-intensity training (program common). The program of interval group was included 4 repeats × 4 minutes at 90-95% peak of heart rate (HR) and continuous group, 60-80 minute at 70-85% peak HR, three sessions per week for 8 weeks. Functional capacity (VO2 peak), distance traveled, time to exhaustion and maximum heart rate (HRmax) were assessed during the Bruce exercise stress test before and after the training program. The collected data were analyzed using the one-way analysis of variances (ANOVA) and post hoc Fisher's least significant difference (LSD) tests. Findings: Functional capacity was increased significantly following the both of training programs with no significant difference between the two groups (P < 0.05). The increases in traveled distance, time to exhaustion, and HRmax after interval program were more in interval program group (P < 0.05). Conclusion: It seems that both high-intensity interval and moderate-intensity continuous training improve functional capacity in cardiac patient with cardiac diseases after coronary artery bypass sugery. However, interval training was more beneficial than continuous training in some parameters such as traveled distance, time to exhaustion, and HRmax during exercise stress test.

Background: Coronary artery disease (CAD) is known to be a leading cause of death. Although many studies have revealed a relationship between rate-pressure product and significant coronary artery stenosis in patients with a positive exercise stress test, there have been few studies on the subject in Thailand. Rate-pressure product results were reviewed of exercise stress tests performed at a single center in Thailand. Objective: To determine a relationship between rate-pressure product and significant coronary artery stenosis in patients with positive exercise stress test. Material and Method: A retrospective cross-sectional study was performed by collecting medical records of patients who had a positive exercise stress test confirmed by cardiac catheterization in Rajavithi Hospital between 1 January 2009 and 31 December 2014. Results: A total of 126 patients were enrolled. Eighty-six patients (68.3%) were male, the mean age was 58.09±8.67 years and the mean body mass index was 25.60±3.55 kg/m². Although the study found that patients in the group with rate-pressure product >30,000 bpm•mmHg had more non-significant coronary artery stenosis (35.3%) than those in the group with ratepressure product <30,000 bpm•mmHg (20.02%), the differences were not statistically significant (p-value = 0.163). The group without significant coronary artery stenosis had a higher mean rate-pressure product (27,370.75±5,190.89 bpm•mmHg) than the group with significant coronary artery stenosis (22,605.50±5,588.57 bpm•mmHg) (p-value <0.001). Conclusion: A high rate-pressure product (≥30,000 bpm•mmHg) is not associated with coronary artery stenosis in patients with positive exercise stress test. Patients without significant coronary artery stenosis had a higher average rate-pressure product. [ABSTRACT FROM AUTHOR]

The aim of the present study was to compare differences in heart rate response following a treadmill exercise test in elderly obese women categorized into groups based on relative handgrip strength. Eighty-eight obese elderly women who were between the ages of 60 and 87 participated in the study and were categorized and enrolled to one of two groups based on lower (< 1.51 m2) or higher (≥ 1.51 m2) relative handgrip strength, respectively. The heart rate recovery in the first and second minutes following the treadmill exercise test and the chronotropic index were compared between groups. The higher relative handgrip strength group presented a significantly higher peak heart rate during exercise and a quicker heart rate recovery following exercise versus the lower relative handgrip strength group (p<0.05). Furthermore, there was a tendency (p=0.059) toward a significantly greater chronotropic index in the higher versus the lower relative handgrip strength group. In conclusion, elderly women with greater relative handgrip strength also demonstrated a better heart rate response during and following exercise, possibly indicating better autonomic balance. The relative handgrip strength might be an important and inexpensive tool for the elderly obese women to indirect assess cardiovascular health. [ABSTRACT FROM AUTHOR]

Background The eligibility of patients with Brugada syndrome (BrS) for implantation of a subcutaneous implantable cardioverter defibrillator (S-ICD) is not well known. This study aimed to clarify the eligibility of BrS patients for S-ICD using electrocardiography (ECG) at rest and during exercise testing. We also analyzed factors associated with ineligibility for S-ICD from standard 12-lead ECG at rest. Methods We enrolled 110 consecutive BrS patients who visited Okayama university hospital from December 2015 to December 2016. All patients were assessed for S-ICD eligibility, which required one lead to satisfy the S-ICD screening template. We assessed standard 12-lead ECG parameters in all participants. Of those who passed S-ICD screening, 45 patients were assessed for S-ICD eligibility during treadmill stress test. Results Mean age of study patients was 54 ± 13 years and 108 (98%) were men. In total, 89 patients (81%) satisfied S-ICD indications at rest. Existence of complete right bundle branch block (CRBBB) on standard 12-lead ECG was a significant predictor of ineligibility for S-ICD (odds ratio, 5.00; P = 0.03; 95%CI, 1.14-21.98). Of the 45 patients who underwent treadmill stress testing, 11 patients (24%) showed ineligibility for S-ICD during the test. Conclusion CRBBB was a predictor of ineligibility for S-ICD in patients with BrS. Sinus tachycardia changes ECG morphology in some patients and stress testing should be considered before S-ICD implantation. [ABSTRACT FROM AUTHOR]

BACKGROUND This study was designed to examine the effects of a lifestyle modification on the improvement in an exaggerated systolic blood pressure (SBP) response to exercise in normotensive females. METHODS The subjects were 78 normotensive females with (n = 25) and without (n = 53) an exaggerated SBP response to exercise who were not taking any medications. An exaggerated SBP response to exercise was defined according to the criteria of the Framingham Study (peak SBP: ≥190 mm Hg). A lifestyle modification program consisting of aerobic exercise and diet counseling was conducted for 12 weeks. The brachial-ankle pulse wave velocity (baPWV), plasma nitrate/nitrite (NOx), plasma thiobarbituric acid-reactive substances (TBARS), high-sensitivity C-reactive protein, fibrinogen levels, and the white blood cell (WBC) counts were measured before and after 12-week intervention. RESULTS After 12-week intervention, the exercise-induced SBP elevation decreased in an exaggerated SBP response group (P < 0.05). In addition, the plasma NOx significantly increased, and the WBC counts and plasma TBARS decreased in an exaggerated SBP response group (P < 0.05). In an exaggerated SBP response group, a stepwise multiple regression analysis showed that the percent change in exercise-induced SBP elevation was independently associated with the percent changes in the plasma NOx level and baPWV (r² = 0.647, P < 0.0001). CONCLUSIONS These results suggest that a lifestyle modification is considered to be important for reducing an exaggerated SBP response to exercise by improving the arterial stiffness and nitric oxide bioavailability. [ABSTRACT FROM AUTHOR]

Objective: To evaluate long-term pulmonary function and airway hyperresponsiveness (AHR) in children following acute influenza lower respiratory tract infection (LRI). Material and Method: Children aged 8 to 18 years who had no underlying disease and were discharged from the hospital for acute influenza LRI at least one year ago were studied. Pulmonary function tests (PFT) (spirometry, body plethysmography) and exercise stress tests were undertaken. Exercise-induced AHR was evaluated by serial spirometries after the maximal exercise. Results: Eighteen children (mean age 12.2±2.6 years, 67% male) were studied. The meantime interval after recovery from acute influenza LRI was 2.5±1.0 years. Fifty-six percent had acute influenza LRI at least two years ago. Abnormal PFT compatible with mild restrictive defect was found in one child who had H1N1-2009 influenza pneumonia 3.2 years ago. Maximal exercise was achieved in 15 children. Exercise-induced AHR was demonstrated in three (20%). All of them had acute influenza LRI more than two years ago. Conclusion: Residual lung function defect and AHR could be found in normal children who had acute influenza LRI more than one year ago. Monitoring of pulmonary function and AHR would be helpful for appropriate respiratory care in otherwise asymptomatic children previously hospitalized with acute influenza LRI. [ABSTRACT FROM AUTHOR]

Objective: Cardiopulmonary fitness depends on daily energy expenditure or the amount of daily exercise. Patients with narcolepsy spent more time being sleepy or asleep than controls; thus we may speculate that they have a lower quantity and quality of physical activity. The aim of the present study was thus to test the hypothesis that exercise tolerance in narcolepsy negatively depends on sleepiness.Patients and Methods: The cross-sectional study included 32 patients with narcolepsy with cataplexy, 10 patients with narcolepsy without cataplexy, and 36 age- and gender-matched control subjects, in whom a symptom-limited exercise stress test with expired gas analysis was performed. A linear regression analysis with multivariate models was used with stepwise variable selection.Results: In narcolepsy patients, maximal oxygen uptake (VO2peak) was 30.1 ± 7.5 mL/kg/min, which was lower than 36.0 ± 7.8 mL/kg/min, p = 0.001, in controls and corresponded to 86.4% ± 20.0% of the population norm (VO2peak%) and to a standard deviation (VO2peakSD) of -1.08 ± 1.63 mL/kg/min of the population norm. VO2peak depended primarily on gender (p = 0.007) and on sleepiness (p = 0.046). VO2peak% depended on sleepiness (p = 0.028) and on age (p = 0.039). VO2peakSD depended on the number of cataplexy episodes per month (p = 0.015) and on age (p = 0.030).Conclusions: Cardiopulmonary fitness in narcolepsy and in narcolepsy without cataplexy is inversely related to the degree of sleepiness and cataplexy episode frequency. [ABSTRACT FROM AUTHOR]

Objectives: To test, if in octogenarians, treadmill exercise with myocardial perfusion imaging (exercise-MPI) can risk stratify for large artery or chronic CAD-related ischemic stroke (LACCIS).Methods: Exercise-MPI-related data of 237 octogenarians (55% prior MI or revascularization) without previous stroke were registered and prospective follow-up was performed to document LACCIS. LACCIS was defined as acute onset of neurological symptoms with CT/MRI findings of non-lacunar-type infarcts in the absence of atrial fibrillation or intracardiac embolic sources.Results: After 7.3 years, 10 LACCIS were documented. SSS [HR 1.08 (1.02-1.13 95% CIs), SDS [HR 1.1 (1.04-1.16 95% CIs)], and non-sustained VT or transient AV block during exercise [HR 3.9 (1.7-9.0 95% CIs)] were predictors of LACCIS (P < .01 for all). A SSS threshold of 16 had 81% specificity for identification of future LACCIS and risk groups formed according to this cut-off had significantly different LACCIS-free survival (P = .015).Conclusion: Exercise-MPI in octogenarians can provide risk stratification markers for LACCIS. [ABSTRACT FROM AUTHOR]

Objectives: Many patients with Fontan physiology are unable to achieve the minimum criteria for peak effort during cardiopulmonary exercise testing. The purpose of this study is to determine the influence of physical activity and other clinical predictors related to achieving peak exercise criteria, signified by respiratory exchange ratio ≥ 1.1 in youth with Fontan physiology., Methods: Secondary analysis of a cross-sectional study of 8-18-year-olds with single ventricle post-Fontan palliation who underwent cardiopulmonary exercise testing (James cycle protocol) and completed a past-year physical activity survey. Bivariate associations were assessed by Wilcoxon rank-sum test and simple regression. Conditional inference forest algorithm was used to classify participants achieving respiratory exchange ratio > 1.1 and to predict peak respiratory exchange ratio., Results: Of the n = 43 participants, 65% were male, mean age was 14.0 ± 2.4 years, and 67.4% (n = 29) achieved respiratory exchange ratio ≥ 1.1. Despite some cardiopulmonary exercise stress test variables achieving statistical significance in bivariate associations with participants achieving respiratory exchange ratio > 1.1, the classification accuracy had area under the precision recall curve of 0.55. All variables together explained 21.4% of the variance in respiratory exchange ratio, with peak oxygen pulse being the most informative., Conclusion: Demographic, physical activity, and cardiopulmonary exercise test measures could not classify meeting peak exercise criteria (respiratory exchange ratio ≥ 1.1) at a satisfactory accuracy. Correlations between respiratory exchange ratio and oxygen pulse suggest the augmentation of stroke volume with exercise may affect the Fontan patient's ability to sustain high-intensity exercise.

Exertional syncope has been suggested to correlate with a cardiac aetiology, particularly when occurring in mid-stride. The aim of the study is to evaluate the incidence of cardiac disease among children presenting with exertional syncope, determine the influence of timing within activity, and determine the utility of genetic testing and implantable event monitors in the evaluation of cardiac syncope. The patients ≤18 years old with exertional syncope who underwent exercise stress testing between 2008 and 2019 were retrospectively included. Patients were assessed to be in one of three groups: mid-exertion (mid-stride syncope), peri-exertion (syncope during activity but not moving), and post-exertion (within minutes of the activity). A total of 334 patients were included; 46 % were mid-exertion, 18 % were peri-exertion, and 36 % were post-exertion. Thirteen patients (3.8 %) were diagnosed with cardiac syncope; n = 9 (69 %) mid-exertion. Only mid-exertional syncope was significantly associated with a cardiac diagnosis (OR: 2.6). Cardiac diagnoses included inherited arrhythmia syndromes (n = 9), abnormal coronary origins (n = 2), and supraventricular tachycardia (n = 2). Only catecholaminergic polymorphic ventricular tachycardia (n = 5) was associated with mid-exertional syncope (OR: 1.4). The definitive diagnostic test was exercise testing (n = 8), echocardiogram (n = 2), genetic testing (n = 1), ambulatory monitor (n = 1), and EKG (n = 1). Mid-stride syncope was more likely to result in a cardiac diagnosis, and exercise testing is the most common definitive test as catecholaminergic polymorphic ventricular tachycardia was the primary aetiology of exertional syncope in our cohort. Implantable event monitors and genetic testing could be helpful in ruling out cardiac disease.

BackgroundThe diagnostic value of the Athens QRS score to detect obstructive coronary artery disease CAD in patients with otherwise normal exercise stress test remains unclear. Methods and ResultsWe analyzed 458 patients who underwent exercise stress test with or without myocardial perfusion imaging within 2 months of coronary angiography from 2008 to 2011. Patients (n=173) with abnormal stress test based on ST segment criteria were excluded. The Athens QRS score ≤5 was defined as abnormal. In our study cohort, 285 patients met the inclusion criteria and were divided into 2 groups: low Athens QRS score (LQRS, n=56), with QRS score ≤5 and normal Athens QRS score normal Athens QRS score, n=229), with QRS score >5. The presence of single‐vessel and multivessel obstructive CAD was higher in LQRS than in normal Athens QRS score patients (47% versus 7.5% and 30% versus 3.8%, respectively, all P

Aim. To study the association between antiischemic effects (AIE) of metoprolol (MP), glucose tolerance, and insulin sensitivity in patients with stable angina (SA). Material and methods. The study included 28 male patients, aged 46-68 years, with stable effort angina, Functional Class II-III, and positive exercise stress test (EST). The time of the ST segment depression by ≥1 mm defined the threshold exercise stress time. MP in a selected dose was administered twice a day, for one month. Its hemodynamic effects were assessed by the dynamics of heart rate (HR), blood pressure (BP), and double product (DP). Glucose tolerance test (GTT) was performed at baseline (before MP administration) and after one month of MP treatment. Tissue insulin sensitivity and insulin resistance (IR) were assessed by ISI0.120 and HOMA-IR parameters, respectively. Results. AIE was registered in 57% of the patients, while 43% failed to demonstrate it. Both groups did not differ by the extent of MP impact on the levels of HR, BP, and DP. The presence or absence of AIE was linked to selected parameters of glucose metabolism. In patients with AIE, the pre-treatment levels of glucose and insulin 2 hours after glucose load were higher (p=0,028 and 0,043, respectively) and ISI1,120 values lower than in patients without AIE (p=0,023). Among participants with AIE, impaired glucose tolerance (IGT) was observed in 4 at baseline and in 8 one month later; among patients without AIE, IGT was not registered. Conclusion. For the first time, the presence of AIE during MP therapy of SA patients was linked to the decreased insulin sensitivity of peripheral tissues (ISI0.120). Paired EST with a single MP dose at baseline provides an opportunity to identify the patients with a higher risk of metabolic disturbances during the longer-term MP treatment.

The aim of this study was to test the hypothesis of differences in performance including differences in ST-T wave changes between healthy men and women submitted to an exercise stress test. Two hundred (45.4%) men and 241 (54.6%) women (mean age: 38.7 ± 11.0 years) were submitted to an exercise stress test. Physiologic and electrocardiographic variables were compared by the Student t-test and the chi-square test. To test the hypothesis of differences in ST-segment changes, data were ranked with functional models based on weighted least squares. To evaluate the influence of gender and age on the diagnosis of ST-segment abnormality, a logistic model was adjusted; P < 0.05 was considered to be significant. Rate-pressure product, duration of exercise and estimated functional capacity were higher in men (P < 0.05). Sixteen (6.7%) women and 9 (4.5%) men demonstrated ST-segment upslope ≥0.15 mV or downslope ≥0.10 mV; the difference was not statistically significant. Age increase of one year added 4% to the chance of upsloping of segment ST ≥0.15 mV or downsloping of segment ST ≥0.1 mV (P = 0.03; risk ratio = 1.040, 95% confidence interval (CI) = 1.002-1.080). Heart rate recovery was higher in women (P < 0.05). The chance of women showing an increase of systolic blood pressure ≤30 mmHg was 85% higher (P = 0.01; risk ratio = 1.85, 95%CI = 1.1-3.05). No significant difference in the frequency of ST-T wave changes was observed between men and women. Other differences may be related to different physical conditioning.

Hypokalemia as a typical feature of primary aldosteronism (PA) is associated with muscle weakness and could contribute to lower cardiopulmonary fitness. The aim of this study was to describe cardiopulmonary fitness and exercise blood pressure and their determinants during a symptom-limited exercise stress test in patients with PA. We performed a cross-sectional study of patients with confirmed PA who were included before adrenal vein sampling on whom a symptom-limited exercise stress test with expired gas analysis was performed. Patients were switched to the treatment with doxazosin and verapamil at least two weeks before the study. In 27 patients (17 male) the VO2peak was 25.4±6.0 ml/kg/min which corresponds to 80.8±18.9 % of Czech national norm. Linear regression analysis shows that VO2peak depends on doxazosin dose (DX) (p=0.001) and kalemia (p=0.02): VO2peak = 4.2 - 1.0 * DX + 7.6 * Kalemia. Patients with higher doxazosin doses had a longer history of hypertension and had used more antihypertensives before examination, thus indicating that VO2peak also depends on the severity of hypertension. In patients with PA, lower cardiopulmonary fitness depends inversely on the severity of hypertension and on lower plasma potassium level. [ABSTRACT FROM AUTHOR]

Introduction: Autonomic neuropathy is a common complication of diabetes mellitus. The aim of the present study was to compare heart rate recovery time and heart rate variation among the indicators of cardiac autonomic function between patients with glucometabolic abnormalities in various levels and normal glucose homeostasis. Methods: A total of 90 patients were enrolled in the study. The patients were divided into four groups: impaired fasting glucose (IFG) (n=18), impaired glucose tolerance (IGT) (n=25), type 2 diabetes mellitus (DM) (n=21), and the control group (n=26). Cardiac autonomic neuropathy (CAN) was evaluated by the maximum exercise stress test and Holter electrocardiography. Results: The baseline heart rate in the DM group was higher than the IFG, IGT, and control groups, but the difference was not statistically significant (93.5±15.5, 87.8±9.4, 84.3±10.8, and 84.3±14.2, respectively; p=0.06). In multiple regression analysis FPG level was an independent variable, increased baseline heart rate was correlated with an elevated FPG level (constant: 71.35, p: 0.004). The metabolic equivalent of task (MET) value was lower in the DM group compared to the IFG, IGT, and control groups (9.9±1.2, 9.0±1.6, 9.78±1.46, 8.77±1.74 p=0.06). Conclusion: When compared to patients with normal glucose homeostasis heart rate at rest was higher in the IGT, IFG, and DM groups. Elevated fasting glucose levels were correlated with an increased baseline heart rate. A negative correlation was found between HbA1c levels and HRRT, and HR index. These finding indicate autonomic functions are impaired in patients with DM, IGT and IFG groups. [ABSTRACT FROM AUTHOR]

Background: Some specifics of cardiac stress protocols, i.e., stressor used or exercise level achieved, may impact myocardial perfusion imaging (MPI) accuracy.Methods: Four-hundred and seventy-five patients were submitted to MPI and coronary angiography. MPI was performed after exercise (303 patients) or dipyridamole stress (172 patients). A coronary stenosis ≥70% was considered significant. In case of exercise test, a peak heart rate (HR) <85% of the maximal age predicted was considered submaximal and categorized as follows: >75% and <85% ("Group 1"); <75% ("Group 2").Results: At coronary angiography, 312/475 (66%) patients showed significant stenosis. In the overall population, MPI showed a high accuracy in unmasking significant coronary stenosis, independently of the stress protocol adopted (AUC .76 for exercise vs .78 for vasodilator; P = NS). However, in case of an exercise stress test, a significant interaction between peak %HR and MPI diagnostic power was evident. While an elevated accuracy was still maintained in "Group 1" patients (AUC .79; P vs maximal exercise = NS), a significant drop was demonstrated in "Group 2" patients (AUC .66; P vs maximal exercise = .012, and P vs "Group 1" = .042).Conclusions: The accuracy of MPI is not influenced by the stress protocol adopted. Exercise MPI maintains an elevated accuracy as long as the %HR remains >75%. [ABSTRACT FROM AUTHOR]

Background Several patients with successful percutaneous coronary interventions (PCIs) show evidence of coronary microvascular dysfunction (CMVD), which can be responsible for persistent positivity of electrocardiographic exercise stress test (EST). In this study, we assessed whether post-PCI CMVD may predict clinical outcome in patients undergoing successful elective PCI of an isolated stenosis of the left anterior descending (LAD) coronary artery. Methods We studied 29 patients (age 64 ± 6, 23 M) with stable coronary artery disease and isolated stenosis (> 75%) of the LAD coronary artery who underwent successful PCI with stent implantation. Coronary blood flow (CBF) velocity response to adenosine and to cold-pressor test (CPT) was assessed in the LAD coronary artery by transthoracic Doppler echocardiography 24 h and 3 months after PCI. The primary end-point was a combination of death, admission for acute coronary syndromes (ACS) or target vessel revascularization (TVR). Results No death or ACS occurred during 36 months of follow-up, but TVR was performed in 5 patients (17.2%). CBF response to CPT at 3 months after PCI was 1.31 ± 0.2 vs. 1.71 ± 0.4 in patients with or without TVR, respectively (p = 0.03), whereas CBF response to adenosine at 3 months in these two groups was 1.70 ± 0.3 vs. 2.05 ± 0.4 (p = 0.059). Conclusions Our data suggest that, in patients with successful PCI of LAD coronary artery stenosis, lower CBF response to the endothelium-dependent vasodilator stimulus CPT is associated with long-term recurrence of restenosis. [ABSTRACT FROM AUTHOR]

Introduction: Kidney disease increases the risk of cardiovascular disease. The corollary of that observation should be that cardiovascular disease would not only increase the risk of kidney dysfunction, but also cause kidney damage, a concept not previously proposed.Materials and Methods: Hemodynamic response to a graded exercise stress test was measured in 70 candidates to evaluate the association of heart rate and blood pressure change, heart rate reserve, chronotropic incompetence (percentage of achievement of maximal predicted heart rate), and circulatory power with development of kidney failure (glomerular filtration rate < 30 mL/min/1.73 m2) during 123 months of follow-up period.Results: Kidney failure was more likely to develop in patients with lower heart rate change, heart rate reserve, percentage of achievement of maximal predicted heart rate, and circulatory power (P = .002, P = .01, P = .02, and P = .008, respectively), even after adjustment for age, resting pulse pressure, hypertension, diabetes mellitus, and exercise test result (hazard ratios, 5.9, 2.9, 3.3, and 2.9, respectively). A resting pulse pressure of 60 mm Hg and higher was accompanied by 7.4 times (95% confidence interval, 1.8 to 30.9) greater risk of developing kidney failure, independent of age and resting systolic blood pressure (P = .006).Conclusions: Hemodynamic responses to a standard graded exercise stress test independently predicted the development of kidney failure. Also, arterial stiffness (represented by resting pulse pressure) could be a factor linking ventricular and kidney function. Early diagnosis of kidney disease should include a cardiovascular assessment and vice versa. [ABSTRACT FROM AUTHOR]

Objective: Cigarette smoking increases the risk of cardiovascular events. The heart rate recovery index (HRRI) is an indicator of autonomous nervous system function and is an independent prognostic risk factor for cardiovascular diseases. In this study, we aimed to evaluate HRRI in heavy smokers. Methods: A total of 179 apparently healthy subjects (67 non-smokers as the control group and 112 heavy smokers) were enrolled into this prospective cross-sectional study. The presence of hypertension, diabetes mellitus, and known cardiac or non-cardiac diseases was specified as the exclusion criteria. Heavy cigarette smoking was defined as the consumption of more than one packet of cigarette per day. All subjects underwent the maximal Bruce treadmill test. HRRIs of the heavy cigarette smoker group at 1, 2, 3, and 5 min after maximal exercise were calculated and compared to those of the control group. Student t-test, chi-square test, and analysis of covariance were used for statistical analysis. Results: The baseline characteristics of the two groups were similar, except for body mass index and high-density lipoprotein level. HRRIs at 1, 2, 3, and 5 min after maximal exercise were found to be significantly lower in the heavy smoker group (HRRI1: 26.78±8.81 vs. 32.82±10.34, p<0.001; HRRI2: 44.37±12.11 vs. 51.72±12.87, p<0.001; HRRI3: 52.73±11.54 vs. 57.22±13.51, p=0.018; and HRRI5: 58.31±10.90 vs. 62.33±13.02, p=0.029). Conclusions: In the present study, we found that HRRI was impaired in heavy smokers. Our results suggest that beside previously known untoward effects on vascular biology, heavy smoking also has deleterious effects on the neuro-cardiovascular system. [ABSTRACT FROM AUTHOR]

Aims The SCORE risk estimation system is used for cardiovascular risk stratification in apparently healthy adults and is based on known cardiovascular risk factors. The purpose of the current study was to evaluate whether exercise capacity can improve the accuracy of the SCORE overall survival risk estimation. Methods and results We investigated 22 878 asymptomatic men and women who were annually screened in a tertiary medical centre. All subjects were free of known ischaemic heart disease, and had completed maximal exercise stress test according to the Bruce protocol. The SCORE risk estimation system was used to evaluate individual cardiovascular risk for all subjects. The primary endpoint was mortality, after exclusion of patients with metastatic cancer during follow-up. The incremental contribution of exercise capacity in predicting the risk of death was evaluated by net reclassification improvement (NRI) and area under the receiver operating curve (AUROC). Mean age of the study population was 47.4±10.3, and 71.6% were men. There were 505 (2.21%) deaths during a mean follow-up of 9.2±4.1 years. Kaplan-Meier survival analysis showed that both SCORE and low exercise capacity were associated with reduced survival. When added to the SCORE risk prediction, exercise capacity allowed more accurate risk stratification: NRI analysis showed an overall improvement of 56.8% in the accuracy of classification and the AUROC increased (0.782 vs. 0.766). Conclusion Both SCORE and exercise capacity are strong independent predictors of all-cause mortality. The addition of exercise capacity to the SCORE risk model can improve the accuracy of the model. [ABSTRACT FROM AUTHOR]

Background: Tissue Doppler Imaging (TDI) is a sensible and feasible method to detect longitudinal left ventricular (LV) systolic dysfunction (LVSD) in patients with diabetes mellitus, hypertension or ischemic heart disease. In this study, we hypothesized that longitudinal LVSD assessed by TDI predicted inducible myocardial ischemia independently of other echocardiographic variables (assessed as coexisting potential markers) in patients at increased cardiovascular (CV) risk.Methods: Two hundred one patients at high CV risk defined according to the ESC Guidelines 2012 underwent exercise stress echocardiography (ExSEcho) for primary prevention. Echocardiographic parameters were measured at rest and peak exercise.Results: ExSEcho classified 168 (83.6 %) patients as non-ischemic and 33 (16,4 %) as ischemic. Baseline clinical characteristics were similar between the groups, but ischemic had higher blood pressure, received more frequently beta-blockers and antiplatelet agents than non-ischemic patients. The former had greater LV size, lower relative wall thickness and higher left atrial systolic force (LASF) than the latter. LV systolic longitudinal function (measure as peak S') was significantly lower in ischemic than non-ischemic patients (8.7 ± 2.1 vs 9.7 ± 2.7 cm/sec, p = 0.001). The factors independently related to myocardial ischemia at multivariate logistic analysis were: lower peak S', higher LV circumferential end-systolic stress and LASF.Conclusions: In asymptomatic patients at increased risk for adverse CV events baseline longitudinal LVSD together with higher LV circumferential end-systolic stress and LASF were the factors associated with myocardial ischemia induced by ExSEcho. The assessment of these factors at standard echocardiography might help the physicians for improving the risk stratification among these patients for ExSEcho. [ABSTRACT FROM AUTHOR]

Background: Exercise stress testing (EST) is crucial to determine cardiovascular (CV) risk in men with erectile dysfunction (ED). Low exercise workload, a slower rate of recovery following exercise, and an impaired capacity to increase heart rate (HR) during exercise testing (chronotropic incompetence) are independent predictors of adverse CV outcomes. Aim of this study was to investigate the association between ED and EST parameters.Methods: A total of 180 ED patients and 50 men without ED underwent maximal EST. Exercise parameters including exercise capacity (metabolic equivalents, METS), peak exercise time, HR at six METS, peak exercise, HR recovery (HRR) at 1 and 2 minutes and chronotropic index (CI) were evaluated in all individuals. Endothelial function was evaluated with flow-mediated dilatation (FMD) of the brachial artery.Results: ED patients had lower peak exercise time and thus lower calculated exercise capacity (P < 0.001) and reduced CI (P < 0.01) compared to men without ED. There was a significant association of ED severity with duration of exercise, peak workload, HRR 2 minutes after exercise, and CI (all P < 0.05). There also was a positive relation of HRR and CI with FMD (all P < 0.05).Conclusions: This study shows interrelationships between exercise capacity, HRR, CI, and ED. Abnormal HRR and CI are associated with systemic endothelial dysfunction. These findings imply pathophysiological links and may have important implications for the estimation of cardiovascular risk in ED patients. [ABSTRACT FROM AUTHOR]

Aims This study aimed to evaluate the role of microvascular dysfunction on left ventricular (LV) longitudinal deformation, filling pressures, and exercise capacity in heart-transplanted (HTx) patients. Methods and Results Fifty-seven HTx patients underwent comprehensive echocardiographic graft function assessment during symptom-limited, semisupine exercise test with simultaneous right heart catheterization. Coronary flow velocity reserve (CFVR) was measured in the left anterior descending artery using pulsed Doppler echocardiography. We divided patients into two groups based on upper and lower median of CFVR. Twenty-six healthy subjects served as controls. Compared with healthy controls, HTx patients had reduced CFVR (P < 0.0001), exercise capacity (P < 0.0001), and LV longitudinal deformation capacity (P < 0.0001). HTx patients in the reduced CFVR group (CFVR < 2.73) were more symptomatic (P < 0.0001) and had higher prevalence of coronary cardiac allograft vasculopathy (CAV) (P < 0.0001) than patients in the high CFVR group. Systolic function improved in both HTx groups during exercise. However, LV longitudinal myocardial deformation improved significantly more in the high CFVR group (P < 0.0001). Peak exercise LV global longitudinal strain and CFVR were strongly correlated (r = 0.8, P < 0.0001). A weak correlation was observed between CFVR and invasive cardiac index at peak exercise (r = 0.35, P < 0.01) and CFVR and LV filling measured by E/e′ ratio (r = −0.41, P < 0.01) and pulmonary capillary wedge pressure (r = −0.30, P < 0.05). Conclusion HTx patients have reduced CFVR, exercise capacity, and LV longitudinal myocardial deformation capacity compared with healthy individuals. HTx patients with reduced CFVR are more symptomatic and have increased prevalence of CAV. Furthermore, reduced CFVR is correlated with reduced LV longitudinal myocardial deformation and exercise capacity. [ABSTRACT FROM AUTHOR]