Stress Echocardiography Testing Research Articles

Exercise limitation in hypertrophic cardiomyopathy: combined stress echocardiography and cardiopulmonary exercise test.

The study aims to investigate exercise-limiting factors in hypertrophic cardiomyopathy (HCM) using combined stress echocardiography and cardiopulmonary exercise test. A symptom-limited ramp bicycle exercise test was performed in the semi-supine position on a tilting dedicated ergometer. Echocardiographic images were obtained concurrently with gas exchange measurements along predefined stages of exercise. Oxygen extraction was calculated using the Fick equation at each activity level. Thirty-six HCM patients (mean age 67±6years, 72% men, 18 obstructive HCM) were compared with age and sex-matched 29 controls. At rest, compared with controls, E/E' ratio (6.26±2.3 vs. 14±2.5, P<0.001) and systolic pulmonary artery pressures (SPAP) (22.6±3.4 vs. 34±6.2mmHg, P=0.023) were increased. Along with the stages of exercise (unloaded; anaerobic threshold; peak), diastolic function worsened (E/e' 8.9±2.6 vs. 13.8±3.6 P=0.011; 9.4±2.3 vs. 18.6±3.3 P=0.001; 8.7±1.9 vs. 21.5±4, P<0.001), SPAP increased (23±2.7 vs. 33±4.4, P=0.013; 26±3.2 vs. 40±2.9, P<0.001; 26±3.5 vs. 45±7mmHg, P<0.001), and oxygen consumption (6.6±1.7 vs. 6.8±1.6, P=0.86; 18.1±2.2 vs. 14.6±1.5, P=0.008; 20.3±3 vs. 15.1±2.1mL/kg/min, P=0.01) was reduced. Oxygen pulse was blunted (6.3±1.8 vs. 6.2±1.9, P=0.79; 10±2.1 vs. 8.8±1.6, P=0.063; 12.2±2 vs. 8.2±2.3mL/beat, P=0.002) due to an insufficient increase in both stroke volume (92.3±17 vs. 77.3±14.5 P=0.021; 101±19.1 vs. 87.3±15.7 P=0.06; 96.5±12.2 vs. 83.6±16.1mL, P=0.034) and oxygen extraction (0.07±0.03 vs. 0.07±0.02, P=0.47; 0.13±0.02 vs. 0.10±0.03, P=0.013; 0.13±0.03 vs. 0.11±0.03, P=0.03). Diastolic dysfunction, elevated SPAP, and the presence of atrial fibrillation were associated with reduced exercise capacity. Both central and peripheral cardiovascular limitations are involved in exercise intolerance in HCM. Diastolic dysfunction seems to be the main driver for this limitation.

Impairment of the adrenergic reserve associated with exercise intolerance in a murine model of heart failure with preserved ejection fraction.

Exercise intolerance is the central symptom in patients with heart failure with preserved ejection fraction. In the present study, we investigated the adrenergic reserve both invivo and in cardiomyocytes of a murine cardiometabolic HFpEF model. 12-week-old male C57BL/6J mice were fed regular chow (control) or a high-fat diet and L-NAME (HFpEF) for 15 weeks. At 27 weeks, we performed (stress) echocardiography and exercise testing and measured the adrenergic reserve and its modulation by nitric oxide and reactive oxygen species in left ventricular cardiomyocytes. HFpEF mice (preserved left ventricular ejection fraction, increased E/e', pulmonary congestion [wet lung weight/TL]) exhibited reduced exercise capacity and a reduction of stroke volume and cardiac output with adrenergic stress. In ventricular cardiomyocytes isolated from HFpEF mice, sarcomere shortening had a higher amplitude and faster relaxation compared to control animals. Increased shortening was caused by a shift of myofilament calcium sensitivity. With addition of isoproterenol, there were no differences in sarcomere function between HFpEF and control mice. This resulted in a reduced inotropic and lusitropic reserve in HFpEF cardiomyocytes. Preincubation with inhibitors of nitric oxide synthases or glutathione partially restored the adrenergic reserve in cardiomyocytes in HFpEF. In this murine HFpEF model, the cardiac output reserve on adrenergic stimulation is impaired. In ventricular cardiomyocytes, we found a congruent loss of the adrenergic inotropic and lusitropic reserve. This was caused by increased contractility and faster relaxation at rest, partially mediated by nitro-oxidative signaling.

Coronary vasospasm testing: escape from the cath lab!

Coronary vasospasm stands as a widely acknowledged and frequent culprit behind chest pain, acute coronary syndrome, and sudden cardiac death, yet it remains a challenging diagnosis. Current guidelines recommend invasive coronary function testing to assess pathophysiology and mechanisms and to define treatment. In reality, this protocol is rarely applied, because it necessitates extended occupation of the cath lab, repetitive administration of nephrotoxic iodine contrast agents, the need for repeated testing on both coronary arteries leading to considerable radiation exposure, and significant direct expenses. The promising perspective for vasospasm testing is a noninvasive approach with advanced echocardiographic techniques, such as transthoracic Doppler echocardiography, with more sensitive indicators of ischemia. Hyperventilation and exercise tests are used for vasospasm directed testing, with assessment of the new parameters: coronary flow velocities and reserve, allowing to see deeper into macro and microvascular pathophysiology. Association between coronary flow, global longitudinal strain and microvascular dysfunction (MVD) and impaired values at hyperemia was previously demonstrated. Reduction in coronary flow velocity (CFV) despite heightened myocardial oxygen consumption and double product during hyperventilation are indicative of coronary vasospasm. Normal coronary angiography finding in patients with documented evidence of ischemia should initiate additional diagnostic testing in order to increase the yield of specific diagnosis in patients with suspected vasospasm, which could help to personalize treatment and prognosis. In order to achieve this, non-invasive provocative stress echocardiography tests should be included in the diagnostic workup. This approach, characterized by its simplicity, feasibility, safety, and efficacy, is currently undergoing extensive testing on a large scale.

Association of abnormal electrocardiography response on dobutamine stress echocardiogram with longer-term major adverse cardiovascular events in women with symptoms of ischemic heart disease.

Prior work demonstrates patients with positive (+) electrocardiogram (ECG) but negative (-) echocardiogram wall motion abnormalities (WMAs) on dobutamine stress echocardiography (DSE) testing have an elevated of major adverse cardiovascular events (MACEs). In this study, we aimed to evaluate the long-term prognosis of women with suspected ischemia with no obstructive coronary artery (INOCA) disease by utilizing core lab read DSE, specifically focusing on those with + ECG findings. Among women with signs and symptoms of myocardial ischemia undergoing clinically indicated coronary angiography enrolled in the Women's Ischemia Syndrome Evaluation (WISE) [1997-2001], a prospective cohort study, 99 underwent standardized DSE by site design. Women with positive DSE (n=17), defined as an increase in score based on wall motion scoring index were excluded except for akinetic to dyskinetic (n=10), providing 82 patients in this analysis. ECG was assessed by core laboratory and (+) ECG was defined as >1 mm ST change. Non-obstructive coronary artery disease (CAD) was assessed by core laboratory quantitative coronary angiography and defined as <50% epicardial stenosis. All-cause death follow-up was an average of 8 years, while adjudicated MACE [all-cause mortality, nonfatal myocardial infarction (MI), nonfatal stroke, heart failure hospitalization] was an average of 5.5 years. Comparisons among subject groups [i.e., (+) ECG and (-) ECG] were made using chi-square or Fisher's exact tests for categorical variables and t-test or Wilcoxon rank-sum test for continuous variables. Demographic profile included a mean age 59±10 years; 55% had hypertension (HTN), 29% diabetes mellitus (DM), and 72% non-obstructive CAD. Overall, 9/82 women (11%) had (+) ECG in the absence of WMAs. There were significant differences in family history of CAD (P=0.009) and vasodilator (P=0.042) use between the (+) ECG and (-) ECG groups, but otherwise had no significant demographic or clinical differences. At longer-term follow up, patients with (+) ECG had higher risk of MACE [unadjusted hazard ratio (HR): 4.91, 95% confidence interval (CI): 1.83, 13.19, P=0.002]. Abnormal stress ECG findings on dobutamine stress testing with a negative DSE should be viewed as an indicator of longer-term risk in women with signs and symptoms of ischemia.

Abnormal workload-indexed blood pressure response to exercise in patients at risk of or with overt heart failure

Abstract Background Conflicting evidence exists regarding the functional and prognostic significance of hypertensive response to exercise (HRE), commonly defined as peak systolic blood pressure (SBP) &amp;gt;210 mmHg in males and &amp;gt;190 mmHg in females. No study yet has explored the impact of sex-specific, workload-indexed HRE in patients at different stages of the heart failure (HF) spectrum, as defined by the American College of Cardiology/American Heart Association HF staging system. Purpose We evaluated the SBP/Workload slope during exercise across the HF spectrum and investigated the hemodynamic, functional and prognostic correlates of HRE. Methods Fifty-eight healthy controls, 201 subjects at risk of developing HF (HF Stages A-B), and 369 patients with a definite diagnosis of HF (Stage C) were enrolled; among the latter, 143 had preserved (HFpEF) and 226 reduced (HFrEF) left ventricular ejection fraction. All patients underwent a combined cardiopulmonary-exercise stress echocardiography test. For each patient, we recorded at least two BP measurements during exercise: the first within the first minute of exercise and the last at peak effort. The SBP/Workload slope was calculated as the difference in SBP over the corresponding increment in watts (W): (SBPpeak – SBPfirst)/(Wpeak – Wfirst). In each ACC/AHA HF Stage, we divided patients according to SBP/Workload slope tertiles; HRE was defined as the highest sex-specific SBP/Workload slope tertile. A composite of all-cause mortality and hospitalization for cardiovascular reasons was chosen as the primary outcome. Results The median SBP/Workload slope was 0.53 (interquartile range 0.36-0.72) mmHg/W and was steeper in women than in men in all subgroups (p&amp;lt;0.0001). After adjusting for age and sex, SBP/Workload slope was significantly higher in Stages A-B (0.61, 0.47-0.75 mmHg/W) and HFpEF (0.63, 0.42-0.86 mmHg/W) compared to controls (0.43, 0.35-0.57 mmHg/W) and HFrEF (0.47, 0.30-0.63 mmHg/W, Figure 1). In all subgroups, patients with HRE showed significantly lower peak oxygen consumption and peripheral oxygen extraction (Table). After a median follow-up of 16 months, HRE was an independent predictor of adverse outcomes (Hazard Ratio 2.05, 95% confidence interval 1.81-5.18), while rest and peak absolute SBP values did not. Kaplan-Meier analysis confirmed a worse survival probability for patients with HRE in Stages A-B and HFpEF but not in HFrEF. After adjusting for confounding factors, the patients with the highest SBP/Workload slope had a 47% higher risk of the primary outcome than subjects in the lowest tertile (Figure 2). Conclusions Across the HF spectrum, patients with HRE, as evaluated by the SBP/Workload slope, present with peculiar pathophysiological features and impaired functional capacity. This is especially true for those in Stages A-B and patients with HFpEF. In these subgroups, HRE may portend an increased risk of adverse cardiovascular outcomes.SBP/workload slopesKaplan-Meier curves and Hazard Ratios

Abstract 13988: Post Stress Test High-Sensitivity Cardiac Troponin I in the Evaluation of Patients With Acute Chest Pain for Enhanced Ischemic Risk Assessment: A Pilot Study

Introduction: High-sensitivity cardiac troponin I (hs-cTnI) assays provide comparable diagnostic information that allow for better detection of myocardial injury. However, hs-cTnI release after cardiac stress testing and its potential utility for identifying inducible myocardial ischemia and risk-stratification are unclear. Aim: This pilot study examined integrating hs-cTnI biomarker testing into cardiac imaging stress testing to improve detection of inducible ischemia and aid in risk-stratification in patients with chest pain being evaluated for acute coronary syndrome (ACS). Methods: We prospectively enrolled 200 consecutive adult patients referred by the Emergency Room for cardiac stress testing for evaluation of possible ACS. A venous blood sample was collected between 0.5 and 2 hours post stress testing; cTnI concentrations were measured in-house by high sensitivity methods. Changes from pre-stress test hs-cTnI concentrations were calculated and association with outcome was explored using a logistic regression model. Results: Patient median age was 62 years, IQR 54-70; 49% were women. ACS known risk factors included hypertension 81.5%, cigarette smoking 49.5% and diabetes 33.5%. Median BMI was 31.63 kg/m 2 , IQR 27.24-35.84. Pre-stress test hs-cTnI median levels were 6 ng/L, IQR 5-9, for women (URL &lt;52 ng/L) and 8 ng/L, IQR 6-12, for men (URL &lt;77 ng/L). A total of 121 patients (60.5%) underwent nuclear stress tests, and 79 (39.5%) received echocardiographic stress tests. Of the 191 samples analyzed, 36% revealed increased hs-cTnI levels from pre-stress test values: 33% in nuclear stress tests (median increase 2 ng/L, IQR 1-5), 41% in echocardiographic stress tests (median increase 2 ng/L, IQR 1-5). In the 155 patients with 6 months of follow-up, changes in post-stress test hs-cTnI levels were not significantly correlated to stress test results, percutaneous coronary interventions or death (p=.85). Conclusion: This study provides insight into the potential of hs-cTnI to aid in identifying inducible myocardial ischemia in a real-world, high-throughput setting. Although a subset of patients exhibited modest increases in hs-cTnI post stress testing, overall, these did not appear to be correlated with inducible myocardial ischemia.

Haemodynamic and metabolic phenotyping of patients with aortic stenosis and preserved ejection fraction: A specific phenotype of heart failure with preserved ejection fraction?

Degenerative aortic valve stenosis with preserved ejection fraction (ASpEF) and heart failure with preserved ejection fraction (HFpEF) display intriguing similarities. This study aimed to provide a non-invasive, comparative analysis of ASpEF versus HFpEF at rest and during exercise. We prospectively enrolled 148 patients with HFpEF and 150 patients with degenerative moderate-to-severe ASpEF, together with 66 age- and sex-matched healthy controls. All subjects received a comprehensive evaluation at rest and 351/364 (96%) performed a combined cardiopulmonary exercise stress echocardiography test. Patients with ASpEF eligible for transcatheter aortic valve replacement (n = 125) also performed cardiac computed tomography (CT). HFpEF and ASpEF patients showed similar demographic distribution and biohumoral profiles. Most patients with ASpEF (134/150, 89%) had severe high-gradient aortic stenosis; 6/150 (4%) had normal-flow, low-gradient ASpEF, while 10/150 (7%) had low-flow, low-gradient ASpEF. Both patient groups displayed significantly lower peak oxygen consumption (VO2 ), peak cardiac output, and peak arteriovenous oxygen difference compared to controls (all p < 0.01). ASpEF patients showed several extravalvular abnormalities at rest and during exercise, similar to HFpEF (all p < 0.01 vs. controls). Epicardial adipose tissue (EAT) thickness was significantly greater in ASpEF than HFpEF and was inversely correlated with peak VO2 in all groups. In ASpEF, EAT was directly related to echocardiography-derived disease severity and CT-derived aortic valve calcium burden. Functional capacity is similarly impaired in ASpEF and HFpEF due to both peripheral and central components. Further investigation is warranted to determine whether extravalvular alterations may affect disease progression and prognosis in ASpEF even after valve intervention, which could support the concept of ASpEF as a specific sub-phenotype of HFpEF.

The Mechanism of Effort Intolerance in Patients with Peripheral Arterial Disease: A Combined Stress Echocardiography and Cardiopulmonary Exercise Test.

We used a combined stress echocardiography and cardiopulmonary exercise test (CPET) to explore effort intolerance in peripheral arterial disease (PAD) patients. Twenty-three patients who had both PAD and coronary artery disease (CAD) were compared with twenty-four sex- and age-matched CAD patients and fifteen normal controls using a symptom-limited ramp bicycle CPET on a tilting dedicated ergometer. Echocardiographic images were obtained concurrently with gas exchange measurements along predefined stages of exercise. Oxygen extraction was calculated using the Fick equation at each activity level. Along the stages of exercise (unloaded; anaerobic threshold; peak), in PAD + CAD patients compared with CAD or controls, diastolic function worsened (p = 0.051 and p = 0.013, respectively), and oxygen consumption (p < 0.001 and p < 0.001, respectively) and oxygen pulse (p = 0.0024 and p = 0.0027, respectively) were reduced. Notably, oxygen pulse was blunted due to an insufficient increase in both stroke volume (p = 0.025 and p = 0.028, respectively) and peripheral oxygen extraction (p = 0.031 and p = 0.038, respectively). Chronotropic incompetence was more prevalent in PAD patients and persisted after correction for beta-blocker use (62% vs. 42% and 11%, respectively). In PAD patients, exercise limitation is associated with diastolic dysfunction, chronotropic incompetence and peripheral factors.

Downstream Imaging Studies Do Not Significantly Improve Outcome in Most Patients with Chest Pain Who Did Not Reach Their Target Heart Rate on a Stress ECHO Study.

Echocardiographic stress tests are often used to evaluate patients who complain of chest pain. However, some patients fail to reach the target heart rate required for the test to be conclusive (usually defined as 85% of the predicted maximal heart rate based on the patient's age) and are often sent for additional imaging tests, such as myocardial perfusion imaging (MPI) or cardiac computed tomography angiography (CTA). Few studies have evaluated the effectiveness of these additional tests in patients who present with chest pain but did not meet the heart rate requirements for a stress test. The primary objective of the study was to evaluate the efficacy of additional imaging tests for patients who experience chest pain during daily activities but are unable to reach the target heart rate currently required for an echocardiographic stress test. The study group included 415 consecutive patients who underwent a stress echocardiogram, did not achieve their target heart rate, and did not demonstrate abnormal changes during the test. The control group consisted of 415 consecutive patients who did reach their target heart rate and demonstrated no signs of ischemia. Demographic and clinical data, medication use, imaging test results (MPI, CTA, and/or coronary catheterization) and documented cardiac events that occurred during 1 year of follow-up were obtained from the electronic medical records. Of the 415 patients in the study group, 73 (17.6%) were referred to another imaging test within 12 months. Of these 73 patients, 59 underwent MPI and 14 underwent cardiac CTA. In 12 of these patients (16.4%) the test was considered to be abnormal, but only 7 patients (1.7%) subsequently underwent a percutaneous intervention (PCI). In the control group, 28 (6.7%) patients were referred for another imaging test. Of these 28 patients, 14 underwent MPI and 14 underwent cardiac CTA. None of these tests were found to be abnormal, but two patients (0.5%) underwent a PCI (p = 0.2 between groups). There were no deaths during the study period and no patients underwent bypass surgery. The majority of the patients who underwent PCI had additional clinical risk factors (diabetes, hypertension, and/or known coronary artery disease), had taken a beta blocker within 24 h prior to the test, and/or did not reach a heart rate above 78% of their target heart rate. Our study suggests that in most patients with chest pain who do not show ischemic changes on a stress echocardiogram, additional imaging studies can be safely deferred, even if the required target heart rate was not reached. However, in patients with diabetes and/or known coronary disease, those who took a beta blocker 24 h prior to the test, or those who did not achieve a heart rate above 78% of the current target heart rate, additional imaging studies should be considered.

Right ventricular functional recovery assessment with stress echocardiography and cardiopulmonary exercise testing after pulmonary embolism: a pilot prospective multicentre study

BackgroundData on right ventricular (RV) exercise adaptation following acute intermediate and high-risk pulmonary embolism (PE) remain limited. This study aimed to evaluate the symptom burden, RV functional recovery during exercise...

WORKLOAD-INDEXED HYPERTENSIVE RESPONSE TO EXERCISE ACROSS THE HEART FAILURE SPECTRUM

Objective: Limited evidence is available regarding the impact of workload-indexed hypertensive response to exercise (HRE) in patients at different stages of the heart failure (HF) spectrum. We evaluated the prevalence, pathophysiologic and prognostic correlates of HRE, evaluated by the systolic blood pressure (SBP)/Workload slope, across the HF spectrum as defined by the American College of Cardiology/American Heart Association. Design and method: We prospectively enrolled 58 healthy controls, 201 subjects at risk of developing HF (HF Stages A-B), and 369 patients with a definite diagnosis of HF (Stage C) and either preserved (HFpEF) or reduced (HFrEF) left ventricular ejection fraction. All patients underwent a combined cardiopulmonary-exercise stress echocardiography test. We recorded two SBP measurements for each patient: the first within the first minute of exercise and the last at peak effort. The SBP/Workload slope was calculated as the difference in SBP over the corresponding increment in watts (W): (SBPpeak – SBPfirst)/(Wpeak – Wfirst). In each subgroup, we divided patients according to SBP/Workload slope tertiles, using sex-specific cut-off values; HRE was defined as the highest SBP/Workload slope tertile in each HF stage. A composite of all-cause mortality and hospitalization for cardiovascular reasons was chosen as the primary outcome. Results: The median SBP/Workload slope was 0.53 (interquartile range 0.36 - 0.72) mmHg/W and was steeper in women than men in all subgroups. After adjusting for age and sex, SBP/Workload slope in controls was similar to HFrEF but significantly lower than Stages A-B and HFpEF. In all HF stages, patients with HRE showed significantly lower peak oxygen consumption and peripheral oxygen extraction. After a median follow-up of 16 months, HRE was independently associated with adverse outcomes (Hazard Ratio 2.05, 95% confidence interval 1.81 - 5.18). Kaplan-Meier analysis confirmed a worse survival probability in Stages A-B and HFpEF, but not HFrEF. After adjusting for clinical and echocardiographic variables, patients in the highest SBP/Workload tertile had a 47% higher risk of the primary outcome than subjects in the lowest tertile. Conclusions: HRE is associated with peculiar pathophysiological features and possibly worse prognosis in patients in the earliest stages of cardiovascular disease and in those with HFpEF.

Functional and prognostic impact of hypertensive response to exercise across the heart failure spectrum

Abstract Funding Acknowledgements Type of funding sources: None. Background Conflicting data exist regarding the prognostic significance of hypertensive response to exercise (HRE), commonly defined according to absolute peak systolic blood pressure (SBP) values. Limited evidence is available regarding the impact of workload-indexed HRE in patients at different stages of the heart failure (HF) spectrum as defined by the American College of Cardiology/American Heart Association HF staging system. Purpose We evaluated the SBP/Workload slope during exercise across the HF spectrum and investigated the haemodynamic, functional and prognostic correlates of HRE. Methods We prospectively enrolled 58 healthy controls, 201 subjects at risk of developing HF (HF Stages A-B), and 369 patients with a definite diagnosis of HF (Stage C); among the latter, 143 had preserved (HFpEF) and 226 reduced (HFrEF) left ventricular ejection fraction. All patients underwent a combined cardiopulmonary-exercise stress echocardiography test. For each patient, we recorded the first (i.e., within the first minute of exercise) and last (i.e., at peak effort) BP measurement during the ramp protocol. The SBP/Workload slope (Figure 1) was calculated as the ratio of the difference in SBP over the corresponding increment in watts (W): (SBPpeak – SBPfirst)/(Wpeak – Wfirst). In each subgroup, we divided patients according to SBP/Workload slope tertiles; HRE was defined as the highest sex-specific SBP/Workload slope tertile in each HF stage. The primary outcome was a composite of all-cause mortality and hospitalization for cardiovascular reasons. Results Median SBP/Workload slope was 0.53 mmHg/W, interquartile range 0.36-0.72 mmHg/W; the slope was 39% steeper in women than in men (p&amp;lt;0.0001). After adjusting for age and sex, SBP/Workload slope in controls (0.43, 0.35-0.57 mmHg/W) was similar to HFrEF (0.47, 0.30-0.63 mmHg/W) but significantly lower than Stages A-B (0.61, 0.47-0.75 mmHg/W) and HFpEF (0.63, 0.42-0.86 mmHg/W). In all HF stages, patients with HRE showed significantly lower peak oxygen consumption and peripheral oxygen extraction. After a median follow-up of 16 months, HRE was independently associated with adverse outcomes (Hazard Ratio 2.05, 95% confidence interval 1.81-5.18), while rest and peak SBP were not. Kaplan-Meier analysis confirmed a worse survival probability in Stages A-B (p=0.005) and HFpEF (p&amp;lt;0.001), but not HFrEF. After adjusting for age, sex, body mass index, rest and peak SBP, rest and peak cardiac output, and rest and peak left ventricular ejection fraction, patients with the highest SBP/Workload slope had a 47% higher risk of the primary outcome than subjects in the lowest tertile (Figure 2). Conclusion HRE, as evaluated by the SBP/Workload slope, is associated with distinct pathophysiological features and impaired functional capacity across the HF spectrum, especially in Stages A-B and in patients with HFpEF. Patients with HRE in these subgroups may be at increased risk of adverse cardiovascular outcomes.

ASSESSMENT OF RISK FACTORS BETWEEN PREMENOPAUSALAND POSTMENOPAUSAL WOMEN PRESENTING WITH ACUTE MYOCARDIAL INFARCTION TO TERTIARY CARE HOSPITAL IN KAKINADA: A CASE CONTROL STUDY

Background: Acute myocardial infarction is a major public health problem in both in developing and developed countries despite impressive strides in the diagnosis and management. Effect of hormone replacement therapy in post-menopausal women is uncertain. Some observational studies suggest that estrogen replacement protects against the incidence of coronary artery disease. Prospective control trials have not yet conrmed the benecial effect of hormone replacement therapy. Hormone replacement therapy shows no benecial effect in reducing the morbidity and mortality both in western and Indian studies. Materials and Methods: This is a case control study conducted by the Department of cardiology, Government General Hospital (tertiary care hospital) Kakinada District, Andhra Pradesh. 200 female patients of Acute Myocardial Infarction were included in the study conducted between December 2021 to November 2022. Results: The mean (Standard deviation) age of patients was 51.05 ± 5.92. peak age of incidence between 51-60 years 60%. Out of 200, 68 were pre-menopausal and 132 were post-menopausal. In pre-menopausal group 77.9% had Unstable Angina, 14.7% with Non ST elevation MI and 7.4% with ST Elevation MI. In post-menopausal group, 27.3% had STEMI, 21.2% had NSTEMI and 51.5% had Unstable Angina. 27.9% in pre-menopausal group and 42.4% in post-menopausal group were having dyslipidemia. Conclusions: Identication of co-morbidities and risk factors of CAD in women will lead us to the correct diagnosis and early appropriate management. Noninvasive tests such as stress echocardiography and perfusion testing with cardiac magnetic resonance or single-photon emission computed tomography imaging should be used in identifying patients at risk, followed by further risk stratication by appropriate invasive testing such as CAG

Deep phenotype characterization of hypertensive response to exercise: implications on functional capacity and prognosis across the heart failure spectrum

Limited evidence is available regarding the role of hypertensive response to exercise (HRE) in heart failure (HF). We evaluated the systolic blood pressure (SBP) to workload slope during exercise across the HF spectrum, investigating haemodynamic and prognostic correlates of HRE. We prospectively enrolled 369 patients with HF Stage C (143 had preserved [HFpEF], and 226 reduced [HFrEF] ejection fraction), 201 subjects at risk of developing HF (HF Stages A-B), and 58 healthy controls. We performed a combined cardiopulmonary exercise stress echocardiography testing. We defined HRE as the highest sex-specific SBP/workload slope tertile in each HF stage. Median SBP/workload slope was 0.53 mmHg/W (interquartile range 0.36-0.72); the slope was 39% steeper in women than men (p < 0.0001). After adjusting for age and sex, SBP/workload slope in HFrEF (0.47, 0.30-0.63) was similar to controls (0.43, 0.35-0.57) but significantly lower than Stages A-B (0.61, 0.47-0.75) and HFpEF (0.63, 0.42-0.86). Patients with HRE showed significantly lower peak oxygen consumption and peripheral oxygen extraction. After a median follow-up of 16 months, HRE was independently associated with adverse outcomes (all-cause mortality and hospitalization for cardiovascular reasons: hazard ratio 2.05, 95% confidence interval 1.81-5.18), while rest and peak SBP were not. Kaplan-Meier analysis confirmed a worse survival probability in Stages A-B (p=0.005) and HFpEF (p < 0.001), but not HFrEF. A steeper SBP/workload slope is associated with impaired functional capacity across the HF spectrum and could be a more sensitive predictor of adverse events than absolute SBP values, mainly in patients in Stages A-B and HFpEF.

Sex differences in heart failure patients assessed by combined echocardiographic and cardiopulmonary exercise testing.

We aimed to test the differences in peak VO2 between males and females in patients diagnosed with heart failure (HF), using combined stress echocardiography (SE) and cardiopulmonary exercise testing (CPET). Patients who underwent CPET and SE for evaluation of dyspnea or exertional intolerance at our institution, between January 2013 and December 2017, were included and retrospectively assessed. Patients were divided into three groups: HF with preserved ejection fraction (HFpEF), HF with mildly reduced or reduced ejection fraction (HFmrEF/HFrEF), and patients without HF (control). These groups were further stratified by sex. One hundred seventy-eight patients underwent CPET-SE testing, of which 40% were females. Females diagnosed with HFpEF showed attenuated increases in end diastolic volume index (P = 0.040 for sex × time interaction), significantly elevated E/e' (P < 0.001), significantly decreased left ventricle (LV) end diastolic volume:E/e ratio (P = 0.040 for sex × time interaction), and lesser increases in A-VO2 difference (P = 0.003 for sex × time interaction), comparing to males with HFpEF. Females diagnosed with HFmrEF/HFrEF showed diminished increases in end diastolic volume index (P = 0.050 for sex × time interaction), mostly after anaerobic threshold was met, comparing to males with HFmrEF/HFrEF. This resulted in reduced increases in peak stroke volume index (P = 0.010 for sex × time interaction) and cardiac output (P = 0.050 for sex × time interaction). Combined CPET-SE testing allows for individualized non-invasive evaluation of exercise physiology stratified by sex. Female patients with HF have lower exercise capacity compared to men with HF. For females diagnosed with HFpEF, this was due to poorer LV compliance and attenuated peripheral oxygen extraction, while for females diagnosed with HFmrEF/HFrEF, this was due to attenuated increase in peak stroke volume and cardiac output. As past studies have shown differences in clinical outcomes between females and males, this study provides an essential understanding of the differences in exercise physiology in HF patients, which may improve patient selection for targeted therapeutics.

Exercise-Induced Pulmonary Hypertension: A Valid Entity or Another Factor of Confusion?

Exercise-induced pulmonary hypertension EIPH has been defined as an increase in mean pulmonary arterial pressure (mPAP) during exercise in otherwise normal values at rest. EIPH reflects heart and/or lung dysfunction and may precede the development of manifest pulmonary hypertension (PH) in a proportion of patients. It is also associated with decreased life expectancy in patients with heart failure with reduced ejection fraction (HFrEF) or left ventricle (LV) valvular diseases. Diastolic dysfunction exacerbated during exercise relates to increased LV filling pressure and left atrial pressure (LAP). In this context backward, transmitted pressure alone or accompanied with backward blood flow promotes EIPH. The gold standard of EIPH assessment remains the right heart catheterization during exercise, which is an accurate but invasive method. Alternatively, non-invasive diagnostic modalities include exercise stress echocardiography (ESE) and cardiopulmonary exercise testing (CPET). Both diagnostic tests are performed under gradually increasing physical stress using treadmill and ergo-cycling protocols. Escalating workload during the exercise is analogous to the physiological response to real exercise. The results of the latter techniques show good correlation with invasive measurements, but they suffer from lack of validation and cut-off value determination. Although it is not officially recommended, there are accumulated data supporting the importance of EIPH diagnosis in the assessment of other mild/subclinical or probably fatal diseases in patients with latent PH or heart failure or LV valvular disease, respectively. Nevertheless, larger, prospective studies are required to ensure its role in clinical practice.

Impact of Exercise-Induced Pulmonary Hypertension on Right Ventricular Function and on Worsening of Cardiovascular Risk in HIV Patients.

Exercise-induced pulmonary hypertension (ExPH) predicts clinical outcomes, such as all-cause mortality and cardiovascular (CV) hospitalizations, in patients with dyspnea on effort. We investigated its prognostic significance in human immunodeficiency virus (HIV)-affected patients. In 52 consecutive HIV patients with either low (n = 47) or intermediate probability (n = 5) of PH at rest, we evaluated-at time 0 and after 2 years-the prognostic determinants of CV risk, according to the 2015 European Society of Cardiology (ESC)/European Respiratory Society (ERS) Guidelines. Patients were classified with or without ExPH at stress echocardiography (ESE) and cardiopulmonary exercise test (CPET). We then related ExPH at time 0 with clinical worsening (CV risk score increase &gt;20% after 2 years). Right ventricle (RV) systolic function was significantly reduced in patients with ExPH compared to those without ExPH at CPET. This also occurred in patients with intermediate/high probability compared to those with low probability of ExPH at ESE. The former exhibited worse values of TAPSE and FAC (p &lt; 0.001 and p = 0.01, respectively). A significantly higher proportion of patients with ExPH (CPET) or with intermediate/high probability of ExPH (ESE) had higher sPAP (p &lt; 0.001), mPAP (p = 0.004) and higher TRV (p = 0.006), as well as higher right atrial area (p &lt; 0.001) and indexed right atrial volume (p = 0.004). Total pulmonary vascular resistance (expressed by the ratio between TRV and the velocity-time integral at the level of the right ventricular outflow tract) was higher both in patients with ExPH and in those with intermediate/high probability of ExPH (p &lt; 0.001). Patients with intermediate/high probability of ExPH at ESE showed a trend (p = 0.137) towards clinical worsening compared to those with low probability of ExPH. No patients with low probability of ExPH had a &gt;20% increased CV risk score after 2 years. We found an association between higher NT-proBNP and the presence or intermediate/high probability of ExPH after 2 years (p = 0.048 at CPET, p = 0.033 at ESE). The assessment of ExPH may predict a trend of increasing CV risk score over time. If confirmed at a longer follow-up, ExPH could contribute to better risk stratification in HIV patients.

Left Ventricular Diastolic Response to Isometric Handgrip Exercise in Physically Active and Sedentary Individuals.

This study aims to investigate the diastolic left ventricular (LV) response to isometric handgrip exercise among healthy middle-aged men with high physical activity levels, versus matched sedentary individuals. Two groups of 10 men aged 41-51 years were studied. Men in the first group had high weekly self-reported physical activity levels (&gt;3000 METs × min/week). In comparison, men in the second group reported low physical activity levels (&lt;300 METs × min/week). An isometric handgrip exercise (IHE) stress echocardiography test was performed in all of them. Both groups showed a similar and statistically significant increase in heart rate, systolic, diastolic, and mean arterial pressure following IHE. The group of active men under study did not show a statistically significant change in the ratio of early diastolic mitral valve inflow velocity to early diastolic lateral wall tissue velocity (E/e' ratio) in response to IHE. Conversely, the inactive participants' E/e' ratio was higher at peak activity in the isometric handgrip exercise. Apparently, healthy middle-aged men with high levels of physical activity seem to have an improved lusitropic cardiac function compared to men with low levels of physical activity, as observed by the different diastolic LV responses induced by isometric handgrip exercise.

Slowing Heart Rate Protects Against Pathological Cardiac Hypertrophy.

We aimed to determine the pathophysiological impact of heart rate (HR) slowing on cardiac function. We have recently developed a murine model in which it is possible to conditionally delete the stimulatory heterotrimeric G-protein (Gαs) in the sinoatrial (SA) node after the addition of tamoxifen using cre-loxP technology. The addition of tamoxifen leads to bradycardia. We used this approach to examine the physiological and pathophysiological effects of HR slowing. We first looked at the impact on exercise performance by running the mice on a treadmill. After the addition of tamoxifen, mice with conditional deletion of Gαs in the SA node ran a shorter distance at a slower speed. Littermate controls preserved their exercise capacity after tamoxifen. Results consistent with impaired cardiac capacity in the mutants were also obtained with a dobutamine echocardiographic stress test. We then examined if HR reduction influenced pathological cardiac hypertrophy using two models: ligation of the left anterior descending coronary artery for myocardial infarction and abdominal aortic banding for hypertensive heart disease. In littermate controls, both procedures resulted in cardiac hypertrophy. However, induction of HR reduction prior to surgical intervention significantly ameliorated the hypertrophy. In order to assess potential protein kinase pathways that may be activated in the left ventricle by relative bradycardia, we used a phospho-antibody array and this revealed selective activation of phosphoinositide-3 kinase. In conclusion, HR reduction protects against pathological cardiac hypertrophy but limits physiological exercise capacity.

Diagnostic accuracy of instantaneous wave-free ratio at rest and during dobutamine provocation to assess myocardial bridging relevance

Abstract Background Diastolic fractional flow reserve (d-FFR) during dobutamine provocation (DOB) was found to be a more reliable physiological index for the functional assessment of myocardial bridging (MB). However, d-FFR calculation is complicated and time-consuming, and therefore several authors have suggested the use of instantaneous wave-free ratio (iFR) to overcome these issues. Purpose The aim of our study was to assess diagnostic performance of d-FFR and iFR at rest and during DOB with exercise-induced myocardial ischemia as reference. Methods Twenty-four symptomatic patients (17 males, mean age 58±8 years) with MB and systolic compression ≥50% diameter stenosis on the left anterior descending (LAD) artery were included. Exercise stress-echocardiography test (SE), and both d-FFR and iFR in the distal segment of LAD at rest and peak DOB (30–50μg/kg/min), were performed in all patients. Optimal cut-off values and diagnostic performance of resting and hyperemic d-FFR and iFR were assessed using SE. Results Exercise-SE was positive for myocardial ischemia in 7/24 patients (29%). The area-under-the-receiver-operating-characteristic curve (ROC-AUC) for exercise-induced myocardial ischemia was 0.64 (95% CI: 0.400–0.885) for resting d-FFR, 0.62 (95% CI: 0.378–0.866) for resting iFR, 1.000 (95% CI: 0.999–1.000) for d-FFR at peak DOB, and 0.96 (95% CI: 0.895–1.000) for iFR at peak DOB. No significant difference in ROC-AUC was observed between d-FFR and iFR at peak DOB (p=0.243). The best cut-off value for both d-FFR and iFR at peak DOB was &amp;lt;0.76 with similar sensitivity and negative predictive values (100 vs. 100% for both), but lower specificity and positive predictive value for iFR in identifying MB associated with exercise-induced ischemia (94% vs. 82%; 88% vs. 70%, respectively). Compared with exercise-induced myocardial ischemia, the diagnostic accuracy of d-FFR and iFR at peak DOB was 96% (kappa=0.903, p&amp;lt;0.001) and 88% (kappa=0.731, p&amp;lt;0.001), respectively. Conclusions iFR during DOB provocation showed similar diagnostic accuracy as d-FFR to identify the functionally significant MB when compared with exercise-induced myocardial ischemia. Funding Acknowledgement Type of funding sources: None.