Patients Undergoing Exercise Stress Testing Research Articles

The combination of high-frequency QRS and ST-segment alterations during exercise stress tests enhanced the diagnostic efficacy for coronary artery disease.

High-frequency QRS (HF-QRS) manifests as a novel adjunct electrocardiographic marker with potential utility in coronary artery disease (CAD) detection. We hypothesize that HF-QRS analysis may be superior to conventional ST-segment analysis in detecting CAD, and the combination of these two analyses in the exercise stress test may enhance the diagnostic efficacy for CAD. The study incorporated a sample of 157 patients (mean age 62 9 years) referred for nonemergent angiography. Before angiography, patients underwent exercise stress testing utilizing an upright bicycle. High-resolution electrocardiogram (ECG) data were collected during the exercise test, facilitating both HF-QRS and conventional ST-segment analyses. The diagnostic efficacy of HF-QRS and ST-segment analysis were compared, utilizing angiographic outcomes as the gold standard. The study design integrated HF-QRS analysis and ST-segment analysis via sequential and concurrent testing protocols. In terms of CAD detection, HF-QRS analysis displayed superior sensitivity compared to conventional ST-segment analysis (63% vs. 37%, p = .002). The serial test significantly increased specificity from 79% to 97% (p = .002) compared to ST-deviation analysis alone. It showed a markedly low sensitivity of 26%. The parallel test significantly increased sensitivity from 37% to 77% (p < .001), while retaining a moderate level of specificity of 51%. The quantity of ECG leads exhibiting a positive HF-QRS response demonstrated a correlation with the severity of CAD (p < .001). HF-QRS analysis exhibited superior sensitivity in detecting angiographically confirmed CAD relative to conventional ST-segment analysis. Moreover, the combination of HF-QRS and ST-segment alterations during exercise stress test enhanced the diagnostic efficacy for CAD.

Abstract 16196: E/e' Predicts Exercise Capacity in Participants Undergoing Exercise Stress Test

Introduction: The ratio of early transmitral flow velocity (E) to early diastolic mitral annular velocity (e’) is a surrogate for left ventricular (LV) filling pressure. Post-stress E/e’ has been shown to predict exercise capacity, but few studies have investigated this correlation with baseline E/e’. Our aim was to evaluate the relationship between baseline E/e’ and exercise capacity during stress test. Methods: All patients undergoing exercise stress testing at University of Virginia from 1/2015 through 9/2015 with the required echo data were included in this study. E/e’ was categorized into quartiles. ANOVA was used to evaluate the relationship between quartiles of E/e’ and exercise duration or METS. Multivariate linear regression was used to adjust for the variables: age, sex, ejection fraction, systolic blood pressure, heart rate, and regional wall motion abnormalities. Results: Baseline characteristics of the 312 participants based on E/e’ quartiles are shown in Table 1; those with higher E/e’, on average, had higher baseline SBP, were older, and had a higher percentage of females. There was a significant difference in exercise duration and METS between E/e’ quartiles (Table 2A) [p &lt; 0.001]. There was an inverse correlation between E/e’ and exercise capacity; the significance was more pronounced with increasing E/e’ (Table 2A) and was present even after adjusting for multiple covariates (Table 2B). Conclusions: Baseline E/e’ correlates with exercise capacity (both duration of exercise and total METS achieved). This suggests that elevated LV filling pressures at rest can predict exercise capacity and may be targeted in future studies to improve exercise tolerance.

Clinical significance of the hemodynamic gain index in patients undergoing exercise stress testing and coronary computed tomography angiography

BackgroundMany hemodynamic parameters provide limited information regarding obstructive coronary artery disease (CAD) during exercise stress testing particularly when exercise is suboptimal. Hemodynamic gain index (HGI) is a recent sensitive indicator of ischemia and has been associated with increased mortality. This study evaluated the clinical impact of HGI in patients who underwent concomitant exercise stress testing and coronary computed tomography angiography (CCTA).MethodsA total of 284 consecutive patients from the executive health program between 2010 and 2018 were identified. Resting and peak heart rate (HR) as well as systolic blood pressure (SBP) measurements were recorded. Framingham risk score (FRS), Duke treadmill score (DTS) and HGI (frac{{{text{HRpeak}} times {text{SBPpeak}} - {text{HRrest}} times {text{SBPrest}}}}{{{text{HRrest}} times {text{SBPrest}}}}) were calculated. The latter was divided into quartiles. CCTA was used as a reference test to detect any CAD. Multivariate analysis and artificial neural network were used to determine the independent predictors of obstructive CAD.ResultsMean age was 53 ± 12 years with 83% male. Mean HGI was 1.74 ± 0.67, with cut-off value of severely blunted HGI ≤ 1.25 (Quartile 4). Patients with severely blunted HGI were older, had higher FRS, and worse DTS. Patients with obstructive CAD had lower HGI when compared to those with normal CCTA/non-obstructive CAD (1.36 ± 0.53 vs. 1.77 ± 0.67, P = 0.005), and showed a higher prevalence of severely blunted HGI (44% vs. 22%, P = 0.019). After adjusting for traditional risk factors, HGI remained an independent predictor of obstructive CAD while severely blunted HGI was associated with threefold increased odds of having obstructive CAD (P = 0.05). Using artificial intelligence analysis, severely blunted HGI independently predicted obstructive CAD with an area under the curve of 0.83 and 0.96, and normalized importance of HGI of 100% and 63%, respectively for different models.ConclusionsAmong patients who underwent concomitant exercise stress testing and CCTA, severely blunted HGI independently predicted obstructive CAD after multivariate adjustment for traditional risk factors.

The interplay among body weight, blood pressure, and cardiorespiratory fitness in predicting atrial fibrillation

BackgroundHypertension, obesity, and low cardiorespiratory fitness (CRF) are known risk predictors for the development of atrial fibrillation (AF) that often interrelate with each other. We examined the interplay of these 3 risk indicators with the occurrence of AF in patients without known cardiovascular disease. MethodsA retrospective analysis of 13,042 patients underwent exercise stress testing (EST). The occurrence of AF during the median follow-up period of 6.8 years was investigated in relation to the presence of obesity (body mass index ≥30 kg/m2), hypertension (blood pressure ≥140/90 mmHg or history of hypertension), or low CRF (exercise capacity <8 metabolic equivalents). Cox proportional hazards models were used to evaluate the individual and combined association between the 3 risk indicators and AF. ResultsThe mean age of the study population was 58 ± 9 years; 49% were women. AF occurred in 499 patients (3.8%). Obesity [hazard ratio (95% confidence interval)], 1.36 (1.12–1.65), hypertension, 1.47 (1.19–1.82), and low CRF, 1.32 (1.06–1.64), were independent risk predictors for AF after multivariable adjustment, including after adjusting for each other and also when the risk predictors were analyzed as continuous variables. In a combined model, a gradual increase in the risk of AF was observed, reaching an adjusted hazard ratio of 2.53 (1.77–3.62) in those with all 3 compared with neither risk indicators. P-for-interaction between hypertension and obesity, or hypertension and low CRF was nonsignificant. ConclusionsObesity, low CRF, and hypertension are independently associated with an excess risk of developing AF in patients without known cardiovascular disease, both individually and more so when coexisting together.

Clinical significance of the hemodynamic gain index in patients undergoing exercise stress testing and coronary computed tomography angiography

Abstract Background Many hemodynamic parameters are used during exercise stress testing but provide limited information regarding obstructive coronary artery disease (CAD) when exercise is suboptimal. Hemodynamic gain index (HGI) is a recently developed and sensitive indicator of ischemia which has been associated with increased mortality. Purpose This study sought to evaluate the clinical impact of HGI in patients who underwent concomitant exercise testing and coronary computed tomography angiography (CCTA). Methods Consecutive patients from the executive health program between 2010 and 2018 were identified. Resting and peak heart rate (HR) and systolic blood pressure (SBP) were recorded. Framingham risk score (FRS), Duke treadmill score (DTS) and HGI [(HRpeak × SBPpeak) − (HRrest × SBPrest)] / (HRrest × SBPrest) were calculated. The latter was divided into quartiles. The presence or absence of any CAD on CCTA was confirmed. Multivariate analysis and artificial neural network were used to determine the independent predictors of obstructive CAD. Results There were 284 patients (mean age 53 years, 83% male). Mean HGI was 1.74±0.67, with severely blunted HGI cut-off of ≤1.25 (Quartile 4). Patients with blunted HGI were older, had higher FRS, and worse DTS. Patients with obstructive CAD showed lower HGI when compared to control (1.36±0.53 vs. 1.77±0.67, P-value 0.005) and had more prevalence of severely blunted HGI ≤1.25 (44% vs. 22%, P-value 0.019). In the multivariate analysis, after adjusting for traditional risk factors, HGI remained independent predictor of obstructive CAD while severely blunted HGI ≤1.25 was associated with 3-fold increased odds of obstructive CAD (P-value 0.05). Using artificial intelligence analysis, blunted HGI remained an independent predictor of obstructive CAD an area under the curve of 0.83 and 0.96, and normalized importance of HGI of 100% and 63%, respectively for different models. Conclusions Among patients who underwent concomitant exercise testing and CCTA, blunted HGI ≤1.25 was strongly associated with obstructive CAD after adjusting for traditional risk factors. HGI is robust, practical, and allows clinicians to reclassify patients, change management, and thus improve prognosis. Funding Acknowledgement Type of funding sources: None.

The Relationship Of Heart Rate Recovery Post Exercise Stress Test To Syntax Values In Patients With Stable Coronary Artery Disease

Background: The prognostic usefulness of abnormal heart rate recovery (HRR) as a predictor of death has been discovered 1–3. Abnormal HRR results from inadequate vagal activation after exercise 4,5. The association between HRR and angiography in CAD (coronary artery disease) has been studied, however the conclusions are still being contested due to a lack of data 6–8. Objectives: The purpose of this study is to see if HRR after an EST (exercise stress test) may predict the severity of syntax values in individuals with stable CAD at Saiful Anwar Hospital Malang (RSSA). Methods: This study is an analytic observational study. It was held in Saful anwar, Malang Hospital during January 2017–December 2019, including 366 patients. All patients underwent exercise stress test for CAD screening and coroner angiography. Those were divided into two groups, which included syntax score &lt; 23 (n=148) and syntax score ≥ 23 (n= 218). Chi-square analysis was used to analyze the relationship correlation between HRR1, HRR2 and Syntax Score, and was used to compared between HRR1 (heart rate recovery first minutes), HRR2 (heart rate recovery second minute) and Syntax Score group. The confounding factor was adjusted with multivariate logistic regression analysis and AUC curve. Results: There was a significant negatif correlation between abnormal HRR1 and HRR2 after exercise and Syntax score, with strong correlation (HRR1 ; OR = -2.11, p = 0.00 AUC :90,8%, HRR2 ; OR = -1,6, p = 0,48, AUC : 70,4%). Conclusion: Decrease HRR at first and second minutes after exercise stress test in stable CAD patient related to higher Syntax Score (&gt;1).

Validation of prognostic value of the hemodynamic gain index in different groups of patients undergoing exercise stress testing

BackgroundRecently, the hemodynamic gain index (HGI) has shown to be a strong independent predictor of all-cause mortality and associated with metabolic equivalents (METs) in a cohort of male patients. However, the prognostic implications of the HGI have never been externally validated with subgroup analyses based on gender, body mass index (BMI) of 35 kg/m2, history of heart failure (HF), coronary artery disease (CAD) and beta-blocker use. MethodsWe identified 126,356 consecutive patients undergoing treadmill exercise testing between January 1st, 1991 and February 27th, 2015. HGI was calculated using the formula: [(SBPpeak × HRpeak) − (SBPrest × HRrest)] / (SBPrest × HRrest). Cox regression models were used to determine the associations between HGI quartiles and all-cause mortality with adjustment for cardiovascular risk factors and exercise testing parameters. ResultsMean age was 53.5 ± 12.6 years. There were 74,724 (59.1 %) male, 5940 (4.7 %) HF, 21,123 (16.7 %) CAD, and 30,568 (24.2 %) beta-blocker-using patients. During the median follow up of 7.1 years, 9929 (7.9 %) died. Median HGI was 1.93 (interquartile range [IQR] 1.40–2.54) bpm/mmHg. After adjustment for the covariates, lower HGI was independently associated with all-cause mortality in the entire cohort (quartile 1 vs 4, adjusted hazard ratio [95 % confidence interval] 1.33 [IQR 1.21–1.45], p < 0.001), and subgroups of men, women, patients with body mass index <35 kg/m2, with and without HF, CAD, and beta-blocker use. The HGI also correlates well with METs in every subgroup. ConclusionsThe HGI is a strong predictor of long-term mortality independently of traditional cardiovascular risk factors, and exercise performance across patient subgroups.

A Validated Model to Identify Patients With Low Likelihood of High-Risk Coronary Artery Disease Anatomy

In stable coronary artery disease (CAD), revascularization improves outcomes only for patients with high-risk coronary anatomy (HRCA). We sought to derive and validate a prediction model, incorporating clinical and exercise stress test characteristics, to identify patients with HRCA. We conducted a retrospective analysis of patients undergoing exercise stress testing at Cleveland Clinic (2005 to 2014), followed by invasive coronary angiography within 3 months. We excluded patients with acute coronary syndrome, known CAD or ejection fraction <50%. HRCA was defined as left main, 3-vessel, or 2-vessel disease involving the proximal left anterior descending artery. Clinical and stress test predictors of HRCA were identified in a multivariable logistic regression model, internally validated with 1,000-fold bootstrapping. The model was then externally validated at the University of Pittsburgh Medical Center (2017 to 2019). The model was derived from 2,758 patients with complete data. HRCA was identified in 418 patients (15.2%) in the derivation cohort. The model consisted of 10 variables: age, male gender, hypertension, hypercholesterolemia, diabetes mellitus, family history of premature CAD, high-density lipoprotein, chest pain, exercise time, and Duke Treadmill Score. Bias-corrected c-statistic was 0.79 (95% confidence interval 0.77 to 0.81) with excellent calibration. In all, 762 patients (27.6%) had a predicted probability and observed prevalence of HRCA <5%. In the validation cohort, the model had a c-statistic of 0.79 (95% confidence interval 0.74 to 0.85) and 210 patients had an observed prevalence of HRCA <5% (40%). In conclusion, an externally validated prediction model, based on clinical characteristics and exercise stress test variables, can identify stable patients with CAD who have HRCA.

P6259Unfavourable vascular risk profile of smokers with testosterone deficiency

Abstract Purpose Testosterone deficiency and cigarette smoking are both associated with increased cardiovascular (CV) mortality risk. We examined whether vascular function and structure parameters are significantly impaired in smokers with low testosterone levels. Methods Carotid intima media thickness (cIMT) and aortic pulse wave velocity (aPWV) were measured in a total of 690 patients (mean 58±7 yrs) without manifest CV/atherosclerotic disease. All patients underwent exercise stress test (and coronary angiography) to reveal coronary artery disease (CAD). Plasma total testosterone (TT) levels were measured in all patients. Results Participants were divided into four subgroups according to smoking (yes/no) and measured low or normal TT levels (low TT&lt;3.5 ng/ml). The subgroups had similar prevalence of hypertension and smoking and comparable LDL-C levels. The mean age of patients with low TT was greater than that of subjects with normal TT (P&lt;0.05). Aortic PWV was significantly higher in smokers with low TT compared to smokers with normal TT (P=0.01) and non-smokers with either low TT (P=0.005) or normal TT (P&lt;0.001) (left plot). Similarly, cIMT was significantly higher in smokers with low TT compared to smokers with normal TT (P=0.01) and non-smokers with either low TT (P=0.005) or normal TT (P&lt;0.001) (right plot). All associations remained statistically significant after adjustment for age. Among smokers with low TT both aPWV and cIMT significantly increased with increasing cigarette smoking intensity (all P&lt;0.05), whereas the associations between smoking intensity and either aPWV or cIMT were not significant among smokers with normal TT concentration (all P=NS). Interestingly, the prevalence of angiographically documented CAD was significantly higher among smokers with low TT (18%) compared to the CAD prevalence of the three other subgroups (overall P&lt;0.001). TT level, smoking and vascular profile Conclusions Carotid IMT and aortic PWV are significantly increased and the prevalence of angiographically documented CAD is greater in smokers with testosterone deficiency. Further studies should be conducted to evaluate how much of the unfavorable effect of both cigarette smoking and testosterone deficiency on coronary atherosclerotic burden is mediated by their associations with function and structure changes in the vascular wall.

Myocardial Ischemia and Mobilization of Circulating Progenitor Cells.

BackgroundThe response of progenitor cells (PCs) to transient myocardial ischemia in patients with coronary artery disease remains unknown. We aimed to investigate the PC response to exercise‐induced myocardial ischemia (ExMI) and compare it to flow mismatch during pharmacological stress testing.Methods and ResultsA total of 356 patients with stable coronary artery disease underwent 99mTc‐sestamibi myocardial perfusion imaging during exercise (69%) or pharmacological stress (31%). CD34+ and CD34+/chemokine (C‐X‐C motif) receptor 4 PCs were enumerated by flow cytometry. Change in PC count was compared between patients with and without myocardial ischemia using linear regression models. Vascular endothelial growth factor and stromal‐derived factor‐1α were quantified. Mean age was 63±9 years; 76% were men. The incidence of ExMI was 31% and 41% during exercise and pharmacological stress testing, respectively. Patients with ExMI had a significant decrease in CD34+/chemokine (C‐X‐C motif) receptor 4 (−18%, P=0.01) after stress that was inversely correlated with the magnitude of ischemia (r=−0.19, P=0.003). In contrast, patients without ExMI had an increase in CD34+/chemokine (C‐X‐C motif) receptor 4 (14.7%, P=0.02), and those undergoing pharmacological stress had no change. Plasma vascular endothelial growth factor levels increased (15%, P<0.001) in all patients undergoing exercise stress testing regardless of ischemia. However, the change in stromal‐derived factor‐1α level correlated inversely with the change in PC counts in those with ExMI (P=0.03), suggesting a greater decrease in PCs in those with a greater change in stromal‐derived factor‐1α level with exercise.ConclusionsExMI is associated with a significant decrease in circulating levels of CD34+/chemokine (C‐X‐C motif) receptor 4 PCs, likely attributable, at least in part, to stromal‐derived factor‐1α–mediated homing of PCs to the ischemic myocardium. The physiologic consequences of this uptake of PCs and their therapeutic implications need further investigation.

Impact of CARDIOrespiratory FITness on Arrhythmia Recurrence in Obese Individuals With Atrial Fibrillation: The CARDIO-FIT Study

BackgroundObesity begets atrial fibrillation (AF). Although cardiorespiratory fitness is protective against incident AF in obese individuals, its effect on AF recurrence or the benefit of cardiorespiratory fitness gain is unknown. ObjectivesThis study sought to evaluate the role of cardiorespiratory fitness and the incremental benefit of cardiorespiratory fitness improvement on rhythm control in obese individuals with AF. MethodsOf 1,415 consecutive patients with AF, 825 had a body mass index ≥27 kg/m2 and were offered risk factor management and participation in a tailored exercise program. After exclusions, 308 patients were included in the analysis. Patients underwent exercise stress testing to determine peak metabolic equivalents (METs). To determine a dose response, cardiorespiratory fitness was categorized as: low (<85%), adequate (86% to 100%), and high (>100%). Impact of cardiorespiratory fitness gain was ascertained by the objective gain in fitness at final follow-up (≥2 METs vs. <2 METs). AF rhythm control was determined using 7-day Holter monitoring and AF severity scale questionnaire. ResultsThere were no differences in baseline characteristics or follow-up duration between the groups defined by cardiorespiratory fitness. Arrhythmia-free survival with and without rhythm control strategies was greatest in patients with high cardiorespiratory fitness compared to adequate or low cardiorespiratory fitness (p < 0.001 for both). AF burden and symptom severity decreased significantly in the group with cardiorespiratory fitness gain ≥2 METs as compared to <2 METs group (p < 0.001 for all). Arrhythmia-free survival with and without rhythm control strategies was greatest in those with METs gain ≥2 compared to those with METs gain <2 in cardiorespiratory fitness (p < 0.001 for both). ConclusionsCardiorespiratory fitness predicts arrhythmia recurrence in obese individuals with symptomatic AF. Improvement in cardiorespiratory fitness augments the beneficial effects of weight loss. (Evaluating the Impact of a Weight Loss on the Burden of Atrial Fibrillation [AF] in Obese Patients; ACTRN12614001123639)

Exercise-induced ventricular re-polarisation changes in moderate congenital aortic valve stenosis.

Introduction Pressure overload increases in patients with moderate aortic valvular stenosis during exercise. In the absence of symptoms, it remains difficult, however, to discriminate patients for surgery based only on pressure overload. Other parameters, such as the dispersion of ventricular re-polarisation (d-QT), which reportedly increases with the transvalvular pressure gradient, have not been fully studied in this condition. To determine the pattern of QT and d-QT response to exercise testing in children with moderate aortic valve stenosis in order to evaluate the impact of pressure overload from an electrophysiological perspective. Materials and methods In all, 15 patients were compared with 15 controls paired for age (14.8±2.5 versus 14.2±1.5 years old) and gender (66.7% male). All the patients underwent exercise stress testing with 12-lead electrocardiograph recording. QT was measured from the onset of QRS to the apex (QTa) at rest, at peak exercise, and at 1 and 3 minutes upon recovery. QT was corrected using the Fridericia equation, and d-QT was calculated. Resting QTc was similar among the study groups, but increased significantly in study patients compared with the control group at maximal effort (p=0.004) and after 1 (p<0.001) and 3 (p<0.001) minutes of recovery. A significant association was identified between groups for d-QT (p=0.034), and post-hoc tests revealed a significant difference only at rest (p=0.001). Ventricular re-polarisation abnormalities can be unmasked and highlighted by the assessment of electrical re-polarisation during exercise challenge in patients with asymptomatic moderate aortic valve stenosis. Using QT response to exercise could be beneficial for better optimisation of risk stratification in these patients.

Impact of choice of imaging modality accompanying outpatient exercise stress testing on outcomes and resource use after revascularization for acute coronary syndromes

Exercise stress testing is commonly obtained after percutaneous coronary intervention (PCI) performed for acute coronary syndromes (ACS). We compared the relationships between exercise echocardiography and nuclear testing after ACS-related PCI on outcomes and resource use. Longitudinal observational study using fee-for-service Medicare claims to identify patients undergoing outpatient exercise stress testing with imaging within 15 months after PCI performed for ACS between 2003 and 2004. Of 63,100 patients undergoing stress testing 3 to 15 months post-PCI, 31,731 (50.3%) underwent an exercise stress test with imaging. Among 29,279 patients undergoing exercise stress testing with imaging, 15.5% received echocardiography. Echocardiography recipients had higher rates of repeat stress testing (adjusted hazard ratio [HR] 2.60, CI 2.19-3.10) compared with those undergoing nuclear imaging in the 90 days after testing, but lower rates of revascularization (adjusted HR 0.87, CI 0.76-0.98) and coronary angiography (adjusted HR 0.88, CI 0.80-0.97). None of these differences persisted subsequent to 90 days after stress testing. Rates of death and readmission for myocardial infarction rates were similar. Total Medicare payments were lower initially after echocardiography (incremental difference $498, CI 488-507), an effect attributed primarily to lower reimbursement for the stress test itself, but not significantly different after 14 months after testing. In this study using administrative data, echocardiography recipients initially had fewer invasive procedures but higher rates of repeat testing than nuclear testing recipients. However, these differences between echo and nuclear testing did not persist over longer time frames.

Exercise-Induced Hypertension, Cardiovascular Events, and Mortality in Patients Undergoing Exercise Stress Testing: A Systematic Review and Meta-Analysis

The prognostic relevance of a hypertensive response to exercise (HRE) is ill-defined in individuals undergoing exercise stress testing. The study described here was intended to provide a systematic review and meta-analysis of published literature to determine the value of exercise-related blood pressure (BP) (independent of office BP) for predicting cardiovascular (CV) events and mortality. Online databases were searched for published longitudinal studies reporting exercise-related BP and CV events and mortality rates. We identified for review 12 longitudinal studies with a total of 46,314 individuals without significant coronary artery disease, with total CV event and mortality rates recorded over a mean follow-up of 15.2±4.0 years. After adjustment for age, office BP, and CV risk factors, an HRE at moderate exercise intensity carried a 36% greater rate of CV events and mortality (95% CI, 1.02-1.83, P = 0.039) than that of subjects without an HRE. Additionally, each 10mm Hg increase in systolic BP during exercise at moderate intensity was accompanied by a 4% increase in CV events and mortality, independent of office BP, age, or CV risk factors (95% CI, 1.01-1.07, P = 0.02). Systolic BP at maximal workload was not significantly associated with the outcome of an increased rate of CV, whether analyzed as a categorical (HR=1.49, 95% CI, 0.90-2.46, P = 0.12) or a continuous (HR=1.01, 95% CI, 0.98-1.04, P = 0.53) variable. An HRE at moderate exercise intensity during exercise stress testing is an independent risk factor for CV events and mortality. This highlights the need to determine underlying pathophysiological mechanisms of exercise-induced hypertension.

Preoperative exercise heart rate recovery predicts intraoperative hypotension in patients undergoing noncardiac surgery

Study ObjectiveTo assess the predictive role of heart rate (HR) recovery in the detection of intraoperative hypotension in patients undergoing noncardiac surgery. DesignProspective, observational study. SettingDepartment of cardiology and operating rooms of university hospitals. Patients160 ASA physical status 1 and 2 patients scheduled for elective noncardiac surgery. MeasurementsAll patients underwent exercise stress testing. Maximum HRs and metabolic equivalent levels were recorded. Heart rate recovery at the first, second, and third minutes were calculated by subtracting HRs one, two, and three minutes into the recovery period from the maximal HR at peak exercise. A decrease in mean arterial pressure (MAP) of greater than 30% was defined as intraoperative hypotension and recorded. Patients were classified to two groups according to whether they had intraoperative hypotension. Main ResultsHypotensive episode was observed in 31 patients (19.7%) during the operation. The presence of diabetes mellitus was higher in patients with intraoperative hypotension (22.6% vs 7.1%, P = 0.019). Mean HR recovery at the first, second, and third minutes was significantly lower in the intraoperative hypotension group (P = 0.001, P = 0.004, and P = 0.031, respectively). Heart rate recovery at the first, second, and third minutes was a good predictor of intraoperative hypotension, but only HR recovery at the first minute (OR 0.82, 95% CI 0.73 to 0.92, P = 0.001) and HR recovery at the second minute (OR, 0.90; 95% CI, 0.82 to 0.98; P = 0.019) were independent predictors of intraoperative hypotension. A higher negative correlation was noted between the degree of MAP reduction and HR recovery at the first minute (r = -0.797, P = 0.001). ConclusionsAbnormal preoperative exercise HR recovery predicts intraoperative hypotension in patients undergoing noncardiac surgery. Given the importance of intraoperative hypotension, preoperative use of exercise testing might be considered.

The use of basic clinical and exercise variables in postmenopausal women for the diagnosis of coronary artery disease

The diagnostic utility of clinical and exercise parameters in women with possible coronary artery disease are underestimated and considered unreliable, in most cases. This seems to be mainly due to the lower likelihood of the disease in selected populations. In this study, postmenopausal women with variable clinical and exercise parameters were tried to be correlated with significant coronary artery disease. One hundred twenty patients with atherosclerotic risk factors, typical angina, or atypical chest pain with ischemic ECG changes were involved. All patients underwent exercise stress test, and 110 suitable patients had coronary angiography. Nonsignificant and significant coronary stenoses (50% narrowing, at least) were investigated due to the parameters involved. Single vessel disease was detected as the most extensive form of the disease, whereas significant lesions correlated only with diabetes, peripheral artery disease, multiple risk factors, typical angina at exercise, insufficient maximum workload, and early ST/T changes. A positive predictive value of 78.5% and a negative predictive value of 80% were determined. The diagnosis of significant coronary artery disease, using basic parameters, is similar to that of men, provided that factors leading to lower likelihood of the disease are excluded. This is a contrasting result with earlier studies which imply unreliable results attributable to female gender.

The association of glomerular filtration rate and erectile dysfunction with severity of coronary artery disease in patients presenting with chest pain

The most common cause of death in patients with chronic kidney disease is cardiovascular. Coexistence of reduced estimated glomerular filtration rate (eGFR) and erectile dysfunction (ED) may predate severe underlying coronary artery disease (CAD). The aim of this study was to evaluate the predictive value of presence and severity of ED and reduced estimated eGFR in the risk stratification of CAD in patients with chest pain. Two hundred and sixty-five consecutive male patients with chest pain were included. All patients underwent exercise stress test (EST), of whom those with positive EST underwent coronary angiography. eGFR was calculated and sexual health inventory for men (SHIM) form was applied to evaluate ED. The relation between SHIM scores, eGFR and the number of arteries with significant lesions was evaluated. Of the 265 male patients, 105 had positive EST while the remaining 160 patients had negative EST. ED was present in 62 patients (38.8%) in the EST (-) group and in 64 patients (61%) in the EST (+) group (P = 0.000). In the EST (+) group, coronary angiography (CAG) revealed normal coronary anatomy or insignificant coronary lesions in 19 (18%), one-vessel disease in 45 (43%), two-vessel disease in 22 (21%) and three-vessel disease in 19 (18%) patients, respectively. The lowest ED prevalence (36.8%) was seen in patients who had normal coronary anatomy or insignificant coronary lesions while the highest prevalence was in those with three-vessel disease (89.5%). When eGFR were taken into account, there was a significant difference between the groups as well (107.2 ± 19.2 ml/min in the EST (-) group versus 94.1 ± 20.0 ml/min in the EST (+) group; P = 0.001). The presence and severity of ED and reduced eGFR are associated with the severity of underlying CAD in patients presenting with chest pain, and they could be implemented in the risk stratification of these patients.

P5-40: T-wave amplitude is a more sensitive marker of myocardial ischemia than ST-segment changes in patients undergoing exercise stress testing

P5-40: T-wave amplitude is a more sensitive marker of myocardial ischemia than ST-segment changes in patients undergoing exercise stress testing

Angiographic Evaluation of High-Risk Treadmill Scores in Patients With Unstable Angina According to Sex, Age, or Use of Drugs With a Negative Chronotropic Effect

The aim of the study is to determine whether age, sex, or the use of drugs with a negative chronotropic effect modifies the sensitivity, specificity, positive or negative predictive value, or positive or negative likelihood ratio of the high-risk criteria used in exercise testing as defined by the Spanish Society of Cardiology (SEC) and the American College of Cardiology/American Heart Association (ACC/AHA), the Duke treadmill score, the Veterans Affairs and West Virginia prognostic score, or the ST/Heart Rate Index at the time when left main coronary artery disease, three-vessel disease or two-vessel disease involving the proximal left anterior descending artery is detected by coronary angiography. The study included a cohort of 469 consecutive patients aged 75 years who were admitted to hospital for unstable angina. All patients underwent exercise stress testing and coronary angiography. In all situations, the ACC/AHA high-risk criteria had the highest sensitivity, negative predictive value, and negative likelihood ratio, and the Duke Treadmill Score had the highest specificity and positive predictive value. The diagnostic accuracy of the other treadmill scores was affected by sex, age or the use of drugs with a negative chronotropic effect. The ACC/AHA high-risk criteria and Duke Treadmill Score provided useful additional information during the assessment of ST-segment depression. These measures could help improve the diagnostic accuracy of conventional ECG exercise testing in women, older individuals, and patients taking beta-blockers or non-dihydropyridine calcium antagonists.

QT dispersion in single coronary artery disease: is there a relation between QT dispersion and diseased coronary artery or lesion localization?

It has been shown that QT dispersion (QTD) increases during episodes of myocardial ischemia or infarction. However, no extensive data on the relation between the diseased coronary artery or the localization of stenosis and the QTD are available. The aim of the study was to examine the relation between QTD and diseased coronary artery and lesion localization during exercise stress test in patients with single coronary artery disease without prior myocardial infarction. One hundred nineteen patients with single coronary artery disease and 53 patients with normal coronary arteries were enrolled in study. All patients underwent exercise stress test with modified Bruce protocol, and QT interval parameters were measured at rest and at minute 2 of the recovery (rec-2) period. QT dispersion at rest was found higher in all single-vessel disease groups compared with that in the control group, and corrected QT dispersion at rec-2 period was also markedly higher in left anterior descending, circumflex, and right coronary artery groups compared with that in the control group. No relation was found between QT dispersion and diseased coronary artery or the lesion localization. In conclusion, no qualitative difference was found between QT dispersion and diseased coronary artery or proximal or distal lesion localization. However, it was observed that patients with single-vessel disease had wider baseline QT dispersion as compared with that in the control group, which further increased significantly with exercise. This finding supports the idea that severity of localized ischemia rather than extent of coronary artery disease would be expected to have a greater effect on inducible QT dispersion.