Cardiac Work Index Research Articles

Associations between 6-min walk distance and cardiopulmonary parameter in non-obese older adults: An observational study.

The 6-min walk test (6MWT) has established itself as a classical field-test for assessing exercise capacity across diverse populations, including older adults. Despite its widespread use, the specific contribution of cardiopulmonary factors to the 6-min walk distance (6MWD) remains relatively unexplored. The primary objective of this investigation was to examine any potential associations between 6MWD and various cardiopulmonary parameters in older adults. Ninety-two non-obese older adults (66.9±4.1 years) were recruited for this study. Real-time assessments of cardiohemodynamic parameters were conducted using impedance cardiography, while cardiopulmonary parameters were evaluated using a gas analyzer during the administration of the 6MWT. Our findings revealed mild-to-strong positive correlations between 6MWD and several cardiohemodynamic parameters, including left cardiac work index, heart rate, cardiac output, and cardiac index, as well as cardiopulmonary parameters such as oxygen consumption (V˙˙O2), carbon dioxide consumption (V˙˙CO2), minute ventilation, oxygen pulse, tidal volume, respiratory exchange ratio (RER), and breath frequency at the end of walking task (p<0.05). Additionally, a negative moderate association was observed between 6MWD and systemic vascular resistance index (SVRi), while no significant correlation was found between stroke volume and 6MWD. Furthermore, a combination of SVRi, V˙˙O2, V˙˙CO2, and RER appeared to predict 6MWD with reasonable accuracy (R2=0.567, p<0.001). Our investigation highlights a robust association between cardiopulmonary parameters and 6MWD among non-obese older adults. These results also emphasize the potential impact of systemic vascular health on submaximal exercise capacity evaluation within the community-dwelling older adults.

Abstract 4113405: The Role of Cardiac Power Output and Stroke Work Index in Balloon Pulmonary Angioplasty Therapy for Chronic Thromboembolic Pulmonary Hypertension

Background: Right ventricular (RV) and left ventricular (LV) measures of cardiac power output (CPO) and stroke work index (SWI) are existing markers of cardiac function and clinical outcomes. These metrics have not been used to evaluate the effects of balloon pulmonary angioplasty (BPA) therapy in patients with chronic thromboembolic pulmonary hypertension (CTEPH). Methods: CTEPH patients who underwent at least six BPA sessions and were included in the UC San Diego BPA registry were included for analysis. Left and right ventricular CPO and SWI during each session were recorded. Cardiac output was measured using the thermodilution technique. Differences in continuous variable measurements before versus after BPA therapy were evaluated using the Student T-test. P-value &lt;0.05 was significant. Results: A total of 66 subjects underwent six consecutive BPA sessions (55.5% female, BMI 28.3±6.10kg/m 2 ,16.7% prior pulmonary thromboendarterectomy surgery) and were included for analysis. Measurements of RV function, including RVCPO (Pre-BPA 0.38±0.14 vs Post-BPA 0.30±0.13 W, p=0.001)(Figure 1) and RVSWI (Pre-BPA 16.52±5.09 vs Post-BPA 14.14±4.00 g*m/beat/m 2 , p=0.004) significantly decreased after BPA therapy. Measurements of LV function, including LVCPO (Pre-BPA 1.00±0.32 vs Post-BPA 1.04±0.31 W, p=0.523) (Figure 2) and LVSWI (Pre-BPA 37.13±10.14 vs Post-BPA 39.73±9.37 g*m/beat/m 2 , p=0.152) did not change significantly after BPA therapy. The ratio of LVCPO/RVCPO increased in stepwise fashion from baseline to the last BPA session (2.82± 0.95 vs. 3.54±1.31 W, p&lt;0.001)(Figure 3). Conclusions: Hemodynamic work expended by the RV decreased after BPA therapy, while work expended by the LV remained unchanged during BPA therapy. The ratio of LV-to-RV work increased in a stepwise manner during consecutive BPA sessions. These measurements may be useful parameters to monitor clinical response to BPA therapy.

Abstract 4115531: Relationship between Ventricular Workload and Functional Response to Balloon Pulmonary Angioplasty (BPA) Therapy for Chronic Thromboembolic Pulmonary Hypertension (CTEPH)

Background: WHO functional classification (FC) is used to evaluate clinical response to BPA therapy and is associated with hemodynamic improvements in CTEPH patients. The relationships between FC and specific metrics of left and right ventricular workload during BPA remain unclear. Methods: CTEPH patients who underwent at least six BPA sessions and were included in the UCSD BPA registry were included for analysis. Left ventricular (LV) and right ventricular (RV) cardiac power output (CPO) and stroke work index (SWI) using thermodilution cardiac output were measured, along with FC, during each BPA session. BPA “responders” showed improved FC from III/IV at baseline to I/II after BPA therapy. BPA “non-responders” had unchanged FC III/IV symptoms before and after BPA therapy. ANOVA and Student T tests were used and P-value &lt;0.05 was significant. Results: A total of 66 subjects (55.5% female, BMI 28.3±6.10kg/m 2 ,16.7% prior pulmonary thromboendarterectomy surgery) were enrolled. Greater subject functionality by FC was significantly associated with higher LVCPO (class IV to I: 0.88±0.15, 0.94±0.28, 1.08±0.31, 0.95±0.27 watt; p&lt;0.001), higher LVSWI (29.4±6.6, 35.6±9.4, 40.8±8.8, 43.4±11.1 g*m/beat/m 2 ; p&lt;0.001), and lower RVCPO (0.37±0.10, 0.34±0.12, 0.34±0.14, 0.24±0.09 watt; p=0.003). RVSWI was not significantly associated with FC (14.8±3.7, 15.4±5.1, 15.1±5.0, 12.5±3.3 g*m/beat/m 2 ; p=0.075). Likewise, higher mean LVCPO (1.1±0.30 vs 0.93±0.27 watt; p&lt;0.001) and LVSWI (41.1±9.1 vs 35.2±9.4 g*m/beat/m 2 ; p&lt;0.001), but not RVCPO or RVSWI, were observed in subjects with FC I/II versus FC III/IV symptoms. BPA responders versus non-responders had higher overall LVCPO (1.01±0.27 vs 0.89±0.27 watt; p&lt;0.001) and LVSWI (39.0±8.9 vs 33.2±8.4 g*m/beat/m 2 ; p&lt;0.001), but not RVCPO (0.33±0.13 vs 0.34±0.13 watt; p=0.465) or RVSWI (15.2±4.8 vs 14.9±5.1 g*m/beat/m 2 ; p=0.694). Responders also had higher baseline LVSWI (p=0.029) and post-BPA LVSWI (p=0.028) compared to non-responders. Conclusions: CTEPH patient functionality and symptoms during BPA therapy are associated with metrics of left and right ventricular workload. Patients with more severe FC III/IV symptoms produce lower LV workload. Treatment responders with improved FC after BPA therapy achieve higher overall, pre-BPA, and post-BPA LV workload. Specific metrics of ventricular workload may be helpful determinants of CTEPH patient symptoms and BPA treatment response.

Correlation Analysis of Activity Levels and Risk Factors in Patients with Stroke: Variations in Cardiac Function According to the Longshi Scale.

This study examined the link between physical activity levels, as measured by the Longshi Scale, and cardiac function and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels in stroke patients, aiming to find correlations with stroke risk factors. The study involved 123 apoplexy patients divided into four groups based on the Longshi Scale: bedridden (31), domestic (32), community (30), and health (30). Clinical data was collected, and hemodynamic assessments were performed using impedance cardiography. Cardiac output time index (CTI) and estimated ejection fraction (EF est) were significantly reduced in both the domestic and community groups compared to the health group (P < 0.05), while diastolic arterial blood pressure (DABP) and systemic vascular resistance index (SVRi) were increased. In the bedridden group, stroke volume (SV), cardiac output (CO), CTI, left cardiac work index (LCWi), and EF est were all lower compared to the health group (P < 0.05), with SVRI and NT-proBNP levels being higher. Additionally, the bedridden group exhibited lower SV, CO, DABP, LCWi, CTI, and EF est when compared to the domestic and community groups (P < 0.05), but higher end-diastolic filling rate (EDFR) and NT-proBNP levels. The Longshi Scale grading positively correlated with SV (r = 0.536, P < 0.01), and NT-proBNP, EF, and cognitive dysfunction were found to be associated with activity levels in stroke patients. The Longshi Scale correlates with cardiac function indicators like NT-proBNP and EF, and can help identify stroke patients at risk of cardiac dysfunction. Moreover, cognitive dysfunction was identified as a significant factor influencing the range of activity in patients with stroke.

#3050 Hemodynamic study of hypertensive disorders in pregnancy using cardiothoracic bioimpedance

Abstract Background and Aims Hypertensive disorders in pregnancy (HDP) are a major cause of maternal and perinatal morbidity and mortality. There is still a need for the development of biomarkers for early diagnosis of the severity of the condition. Thoracic electrical bioimpedance (TEB) is a non-invasive hemodynamic technique based on the resistance to the flow of electrical current. We investigated hemodynamic changes in pregnant/postpartum women with HDP using TEB. Method A retrospective observational study was conducted in pregnant and postpartum women with hypertension monitored by TEB. Indirect changes were analyzed in: cardiac work, left cardiac work index (LCWI kg⋅m/m2) and calculated cardiac output (CO ml/min=systolic volume -SV ml- × heart rate -HR bpm-); fluid status, thoracic fluid content index (TFCI l/kOhm/m2); and resistances, systemic vascular resistance index (SVRI dyn.s.cm-5.m2). Normality of variables was assessed by Shapiro-Wilk test and correlation analysis was performed by Pearson/Spearman tests. Statistical inference between the hypertension-preeclampsia and pregnancy-postpartum groups was performed using Student's/Mann-Whitney U tests. Analysis was performed using STATA 12. Results Fifty-five patients were included with a mean age of 36.5 years (SD 4.54), 69% were older than 35 years. Pregnant women accounted for 86% of the TEB evaluations, the majority (93.6%) in the third trimester. There was chronic hypertension in 7.27% and pre-eclampsia in 18.18% of previous pregnancies. The diagnoses were: pre-eclampsia (56.36%), gestational hypertension (40%) and HELLP syndrome (3.64%). The mean blood pressure was 144/89 (SD 16/11) mmHg. Mean proteinuria was 363.2 (range: 10.3-23220) mg/g. The median values were as follow: LCWI: 5.05 (IQR: 1.4) kg⋅m/m2; CO: 6352 (IQR: 2345) ml/min; TFCI: 17.9 (IQR: 6.3) l/kOhm/m2; SVRI: 2167.63 (SD: 462.87) dyn.s.cm-5.m2. LCWI showed a weak positive correlation with systolic blood pressure (SBP) and a strong correlation with diastolic blood pressure (DBP) (Rho 0.2899 and 0.5176, respectively). There was also a positive and moderate correlation between SVRI and SBP and DBP (r 0.4265 and 0.4019, respectively). There was no correlation between CO or TFCI and SBP or DBP. No statistically significant differences in hemodynamic parameters were found between gestational hypertension and pre-eclampsia, nor between pregnant and postpartum women. Conclusion Increased blood pressure in the setting of HDP correlates with increased LCWI and systemic resistance independent of fluid retention. An increase in systemic vascular resistance measured by TEB (which decreases in normal pregnancy) may be an early diagnostic marker of HDP. These findings require further validation in a larger cohort, including a control group of pregnant women without hypertension.

Accumulating Sedentary Time and Physical Activity From Childhood to Adolescence and Cardiac Function in Adolescence.

Increased physical activity (PA) may mitigate the negative cardiovascular health effects of sedentary behavior in adolescents. However, the relationship of PA and sedentary time from childhood with cardiac function in adolescence remains underexplored. Therefore, we investigated the associations of cumulative sedentary time and PA from childhood to adolescence with cardiac function in adolescence. Participants were 153 adolescents (69 girls) who were aged 6 to 8 years at baseline, 8 to 10 years at 2-year follow-up, and 15 to 17 years at 8-year follow-up. Cumulative sedentary time and PA exposure between baseline and 2-year follow-up and between baseline and 8-year follow-up were measured using a combined accelerometer and heart rate monitor. Cardiac function was assessed using impedance cardiography at 8-year follow-up. The data were analyzed using linear regression analyses adjusted for age and sex. Cumulative moderate to vigorous PA (standardized regression coefficient [β]=-0.323 [95% CI, -0.527 to -0.119]) and vigorous PA (β=-0.295 [95% CI, -0.508 to -0.083]) from baseline to 8-year follow-up were inversely associated with cardiac work at 8-year follow-up. Conversely, cumulative sedentary time had a positive association (β=0.245 [95% CI, 0.092-0.398]). Cumulative vigorous PA from baseline to 8-year follow-up was inversely associated with cardiac work index at 8-year follow-up (β=-0.218 [95% CI, -0.436 to 0.000]). Higher levels of sedentary time and lower levels of PA during childhood were associated with higher cardiac work in adolescence, highlighting the importance of increasing PA and reducing sedentary time from childhood.

Effect of cardiac function in patients with gastrointestinal cancer with or without acute kidney injury assessed using a non-invasive impedance cardiography: a case-control study

ObjectivesThis study aimed to analyze the possible causes of changes in cardiac function and investigate the feasibility of clinical assessment of gastrointestinal cancer in patients with or without acute kidney injury (AKI) assessed using a non-invasive impedance cardiography (ICG, Bioz. Cardio Dynamics, USA) to identify independent risk factors.MethodsPatients admitted to the Fourth Hospital of Hebei Medical University, China, between May 1, 2019, and February 15, 2022, were included in this study. A total of 51 patients with gastrointestinal cancer (31 men and 20 women, mean age 61.1 ± 10.9 years) with or without AKI were evaluated for ICG. A total of 19 patients underwent ultrasound cardiography (UCG) and ICG evaluations.ResultThere was a significant positive correlation between cardiac output (CO), cardiac index (CI), stroke volume (SV), left cardiac work index (LCWI), and ejection fraction (EF) measured using UCG and ICG. The relationship was observed between COICG and COUCG (r = 0.707, P = 0.001), CIICG and CIUCG (r = 0.718, P = 0.001), SVICG and SVUCG (r = 0.837, P < 0.001), and LCWIICG and EFUCG (r = 0.540, P = 0.017). Cardiac function parameters measured using ICG were statistically different between patients with gastrointestinal cancer with or without AKI (P ≤ 0.05). Multivariate analysis revealed that AKI independently affects cardiac function in patients with gastrointestinal cancer.ConclusionsUCG and ICG methods are significantly associated with cardiac function in patients with or without AKI, and patients with gastrointestinal cancer with AKI are worse than those without AKI. AKI is an independent risk factor for cardiac function in patients with gastrointestinal cancer.

Hemodynamic effects of heart rate lowering in patients admitted for acute heart failure: the RedRate-HF Study (Reduction of heart Rate in Heart Failure).

In patients admitted for acute heart failure (HF) indication for drugs which reduce the heart rate (HR) is debated. The multicentre prospective study Reduction of heart Rate in Heart Failure (RedRate-HF) was designed to analyse the hemodynamic effects of an early reduction of HR in acute HF. Hemodynamic parameters were recorded by using the bioimpedance technique, which was shown to be accurate, highly reproducible and sensitive to intra-observer changes. Lowering HR was obtained by ivabradine 5 mg bd, given 48-72 h after admission on the top of optimized treatment. Patients were followed at 24, 48, 72 h after drug assumption and at hospital discharge. Twenty patients of a mean age of 67 ± 15 years, BNP at entry 1348 ± 1198 pg/ml were enrolled. Despite a clinical stabilization, after 48-72 h from admission, HR was persistently >70 bpm. Ivabradine was well tolerated in all patients with a significant increase in RR interval from 747 ± 69 ms at baseline to 948 ± 121 ms at discharge, P < 0.0001. Change in HR was associated with a significant increase in stroke volume (baseline 73 ± 22 vs. 84 ± 19 ml at discharge, P = 0.03), and reduction in left cardiac work index (baseline 3.6 ± 1.2 vs. 3.1 ± 1.1 kg/m2 at discharge, P = 0.04). Other measures of heart work were also significantly affected while cardiac output remained unchanged. The strategy of an early lowering of HR in patients admitted for acute HF on top of usual care is feasible and safe. The HR reduction causes a positive increase in stroke volume and may contribute to saving energy without affecting cardiac output.

High-dose adenosine versus saline-induced cardioplegic arrest in coronary artery bypass grafting: A randomized double-blind clinical feasibility trial.

In this clinical trial, we evaluated if a short-acting nucleoside, adenosine, as a high-dose bolus injection with blood cardioplegia induces faster arrest and provides better myocardial performance in patients after bypass surgery for coronary artery disease. Forty-three patients scheduled for elective or urgent coronary artery bypass grafting were prospectively recruited in two-arm 1:1 randomized parallel groups to either receive 20 mg of adenosine (in 21 patients) or saline (in 22 patients) into the aortic root during the first potassium-enriched blood cardioplegia infusion. The main outcomes of the study were ventricular myocardial performance measured with cardiac index, right ventricular stroke work index, and left ventricular stroke work index at predefined time points and time to asystole after a single bolus injection of adenosine. Conventional myocardial biomarkers were compared between the two groups at predefined time points as secondary endpoints. Electrocardiographic data and other ad hoc clinical outcomes were compared between the groups. Compared with saline, adenosine reduced the time to asystole (68 (95% confidence interval (95% CI) = 37-100) versus 150 (95% CI = 100-210) seconds, p = 0.005). With myocardial performance, the results were inconclusive, since right ventricular stroke work index recovered better in the adenosine group (p = 0.008), but there were no significant overall differences in cardiac index and left ventricular stroke work index between the groups. Only the post-cardiopulmonary bypass cardiac index was better in the adenosine group (2.3 (95% CI = 2.2-2.5) versus 2.1 (95% CI = 1.9-2.2) L/min/m2, p = 0.016). There were no significant differences between the groups in cardiac biomarker values. A high dose adenosine bolus at the beginning of the first cardioplegia infusion resulted in significantly faster asystole in coronary artery bypass grafting patients but enhanced only partially the ventricular performance.EudraCT number: 2014-001382-26. https://www.clinicaltrialsregister.eu/ctr-search/trial/2014-001382-26/FI.

Cardiac function and exercise capacity in patients with metabolic syndrome: A cross-sectional study.

BackgroundMetabolic syndrome is a pre-diabetes condition that is associated with increased cardiovascular morbidity and mortality. We aimed to explore how exercise capacity, cardiac structure, and function were affected in patients with metabolic syndrome.MethodsOutpatients with echocardiography and exercise stress test combined with impedance cardiography (ETT + ICGG) results available from Nov 2018 to Oct 2020 were retrospectively enrolled. Echocardiographic, ETT + ICG profiles, and exercise performance were compared between patients with metabolic syndrome and the ones without. Sensitivity analyses were performed excluding patients without established coronary heart disease and further 1:1 paired for age and gender, respectively. Multiple linear regression was used to find out related predictors for maximal metabolic equivalents (METs).ResultsThree hundred and twenty-third patients were included, among whom 97 were diagnosed as metabolic syndrome. Compared to patients without metabolic syndrome, echocardiography showed that patients with metabolic syndrome had a significantly lower E/A ratio (p < 0.001). Besides, they have larger left atrium, larger right ventricle, and thicker interventricular septum (all p < 0.001), but similar left ventricular ejection fraction (P = 0.443). ICG showed that patients with metabolic syndrome had significantly higher stroke volume at rest and maximum (p < 0.001), higher left cardiac work index at rest and maximum (p = 0.005), higher systemic vascular resistance (SVR) at rest (p < 0.001), but similar SVI (p = 0.888). During exercise, patients with metabolic syndrome had lower maximal METs (p < 0.001), and a higher proportion suffering from ST-segment depression during exercise (p = 0.009). Sensitivity analyses yielded similar results. As for the linear regression model, 6 independent variables (systolic blood pressure, BMI, E/A ratio, the height of O wave, the peak value of LCWi, and the baseline of SVR) had statistically significant effects on the maximal METs tested in exercise (R = 0.525, R2 = 0.246, P < 0.001).ConclusionPatients with metabolic syndrome had significant structural alteration, apparent overburden of left ventricular work index, pre-and afterload, which may be the main cause of impaired exercise tolerance.

Low- to moderate-intensity blood flow restricted walking is not an acute equivalent for unrestricted jogging in young active adults

ABSTRACT This study investigated whether walking with blood flow restriction (BFR) increases acute cardio-respiratory demands to the point that it can be considered an alternative for jogging. Sixteen physically active adults completed five experimental sessions (order randomised), comprising 10 min of treadmill exercise. Two sessions included unrestricted walking, two sessions required walking with BFR cuffs positioned on the lower limbs inflated to 60% of individualised arterial occlusion pressure, and one session was conducted at a jogging pace. Comfortable walking and jogging speeds were calculated during the familiarisation session. Walking speeds were individualised to either 100% (speed: 6.0 ± 0.3km·h-1[low-intensity]) or 120% (speed: 7.2 ± 0.3km·h-1[moderate-intensity]) of comfortable walking speed. The jogging session was unrestricted (speed: 9.1 ± 0.7km·h-1). Initial analysis compared walking conditions across heart rate, left cardiac work index, systolic blood pressure, relative oxygen consumption, minute ventilation, rating of perceived exertion and limb discomfort. Secondary analysis compared the walking session with the highest cardio-respiratory demands to jogging. Initial analysis identified that moderate-intensity with BFR induced the highest cardio-respiratory and perceptual responses compared with any other walking sessions (p < 0.01). Secondary analysis revealed that all cardio-respiratory measures were higher during jogging when compared with moderate-intensity with BFR (p < 0.01), except systolic blood pressure (p = 0.10). All perceptual measures were higher during moderate-intensity with BFR (p < 0.01) compared with jogging. Low- to moderate-intensity BFR-walking produces lower acute cardio-respiratory responses at higher ratings of perceived exertion and discomfort compared with jogging. Overall, BFR-walking does not seem to provide an equivalent exercise modality for unrestricted jogging in physically active adults. Highlights In young active adults, walking with blood flow restriction increases cardio-respiratory demands, yet not to a level equivalent to jogging. Moderate-intensity blood flow restricted walking elicits higher exercise-related sensation of exertion and leg discomfort than jogging. Blood flow restriction application increases exercise severity whereby moderate-intensity BFR-walking and jogging are both considered vigorous-intensity exercise.

Cardiopulmonary exercise testing and impedance cardiography in the assessment of exercise capacity of patients with coronary artery disease early after myocardial revascularization

BackgroundPatients with coronary artery disease (CAD) are characterized by different levels of physical capacity, which depends not only on the anatomical advancement of atherosclerosis, but also on the individual cardiovascular hemodynamic response to exercise. The aim of this study was evaluating the relationship between parameters of exercise capacity assessed via cardiopulmonary exercise testing (CPET) and impedance cardiography (ICG) hemodynamics in patients with CAD.MethodsExercise capacity was assessed in 54 patients with CAD (41 men, aged 59.5 ± 8.6 years) within 6 weeks after revascularization by means of oxygen uptake (VO2), assessed via CPET, and hemodynamic parameters [heart rate (HR), stroke volume, cardiac output (CO), left cardiac work index (LCWi)], measured by ICG. Correlations between these parameters at anaerobic threshold (AT) and at the peak of exercise as well as their changes (Δpeak–rest, Δpeak–AT) were evaluated.ResultsA large proportion of patients exhibited reduced exercise capacity, with 63% not reaching 80% of predicted peak VO2. Clinically relevant correlations were noted between the absolute peak values of VO2 versus HR, VO2 versus CO, and VO2 versus LCWi (R = 0.45, p = 0.0005; R = 0.33, p = 0.015; and R = 0.40, p = 0.003, respectively). There was no correlation between AT VO2 and hemodynamic parameters at the AT time point. Furthermore ΔVO2 (peak–AT) correlated with ΔHR (peak–AT), ΔCO (peak–AT) and ΔLCWi (peak–AT) (R = 0.52, p < 0.0001, R = 0.49, p = 0.0001; and R = 0.49, p = 0.0001, respectively). ΔVO2 (peak–rest) correlated with ΔHR (peak–rest), ΔCO (peak–rest), and ΔLCWi (peak–rest) (R = 0.47, p < 0.0001; R = 0.41, p = 0.002; and R = 0.43, p = 0.001, respectively).ConclusionICG is a reliable method of assessing the cardiovascular response to exercise in patients with CAD. Some ICG parameters show definite correlations with parameters of cardiovascular capacity of proven clinical utility, such as peak VO2.

Age- and Gender-Related Differences in the Hemodynamic Status of Patients with Mild or Moderate Hypertension.

PurposeThe aim of this study was to use non-invasive impedance cardiography (ICG) to determine the hemodynamic status of patients with grade 1 and grade 2 hypertension in relation to gender and age.Patients and MethodsWe analyse prospectively collected data of 158 patients with grade 1 or grade 2 arterial hypertension. Patients were grouped according to age: 1) <50 years and 2) ≥50 years. Hemodynamic status of patients was assessed by using non-invasive ICG. For the purpose of this study two hemodynamic parameters were used: a) systemic vascular resistance index (SVRI) and b) left cardiac work index (LCWI). The primary endpoint was the hemodynamic status of patients. The secondary endpoint was hypertension-mediated organ damage.ResultsIncreased SVRI was assessed in 80% of patients, more common in the ≥50 years group than in the <50 years group (88.5% vs 64.8%; p < 0.01). The occurrence of increased systemic vascular resistance correlates hierarchically with increasing age. Elevated LCWI (hypervolemia and/or hyperinotropy) was present in 63% of patients, more often in males than females (70.3% vs 57.1%; p < 0.05) as well in those <50 years than in older patients (70.4% vs 59.6%; p < 0.05). Patients with diabetes were less likely to have hypervolemia/hyperinotropy than those without diabetes (46.7% vs 67.2%; p < 0.01). Hypervolemia/hyperinotropy (46.7%) and hypovolemia/hypoinotropy (43.3%) were present in a similar percentage of diabetic patients. Left ventricular hypertrophy was found in 30 patients (19%). Patients with left ventricular hypertrophy were more commonly male (66.7% vs 42.2%; p = 0.016) and had increased systemic vascular resistance (96.7% vs 77.3%; p = 0.015) compared to the patients without left ventricular hypertrophy. Hypertensive retinopathy grade III was found in 14 patients (8.9%). Elevated daytime systolic pressure, diabetes and increased age are independent predictors of grade III hypertensive retinopathy. Patients with reduced renal function had higher mean systolic blood pressure (p < 0.05), were more commonly male (p < 0.01) and older (p < 0.01) than those without reduced renal function.ConclusionAlthough there are certain correlations between hemodynamic disorders and age and gender, specific hemodynamic status of an individual patient with hypertension cannot reliably be predicted on the basis of age and gender. The measurement of hemodynamic parameters by ICG can guide the clinician to select appropriate antihypertensive therapy to the patients’ hemodynamic pathophysiologic condition.

Posture-Related Differences in Cardiovascular Function Between Young Men and Women: Study of Noninvasive Hemodynamics in Rural Malawi.

BackgroundCardiovascular risk is higher in men than in women, but little information exists about sex‐related differences in cardiovascular function from low‐income countries. We compared hemodynamics between sexes in rural Malawi in a cohort followed up since their birth.Methods and ResultsSupine, seated, and standing hemodynamics were recorded from 251 women and 168 men (mean age, 21 years; body mass index, 21 kg/m2) using oscillometric brachial waveform analyses (Mobil‐O‐Graph). The results were adjusted for estimated glomerular filtration rate, and plasma potassium, lipids, and glucose. Men had higher brachial and aortic systolic blood pressure and stroke index regardless of posture (P<0.001), and higher upright but similar supine diastolic blood pressure than women. Regardless of posture, heart rate was lower in men (P<0.001), whereas cardiac index did not differ between sexes. Women presented with lower supine and standing systemic vascular resistance index (P<0.001), whereas supine‐to‐standing increase in vascular resistance (P=0.012) and decrease in cardiac index (P=0.010) were higher in women. Supine left cardiac work index was similar in both sexes, whereas standing and seated left cardiac work index was higher in men than in women (P<0.001).ConclusionsIn young Malawian adults, men had higher systolic blood pressure, systemic vascular resistance, and upright cardiac workload, whereas women presented with higher posture‐related changes in systemic vascular resistance and cardiac output. These findings show systematic sex‐related differences in cardiovascular function in a cohort from a low‐income country with high exposure to prenatal and postnatal malnutrition and infectious diseases.

Associations of Vasopressor Requirements With Echocardiographic Parameters After Out-of-Hospital Cardiac Arrest.

Post-arrest hypotension is common after out of hospital cardiac arrest (OHCA) and many patients resuscitated after OHCA will require vasopressors. We sought to determine the associations between echocardiographic parameters and vasopressor requirements in OHCA patients. We retrospectively analyzed adult patients with OHCA treated with targeted temperature management between December 2005 and September 2016 who underwent a transthoracic echocardiogram (TTE). Categorical variables were compared using 2-tailed Fisher's exact and Pearson's correlation coefficients and variance (r2) values were used to assess relationships between continuous variables. Among 217 included patients, the mean age was 62 ± 12 years, including 74% males. The arrest was witnessed in 90%, the initial rhythm was shockable in 88%, and 58% received bystander CPR. At the time of TTE, 41% of patients were receiving vasopressors; this group of patients was older, had greater severity of illness, higher inpatient mortality and left ventricular ejection fraction (LVEF) was modestly lower (36.8 ± 17.1% vs. 41.4 ± 16.4%, P = 0.04). Stroke volume, cardiac power output and left ventricular stroke work index correlated with number of vasopressors (Pearson r -0.24 to -0.34, all P < 0.002), but the correlation with LVEF was weak (Pearson r -0.13, P = 0.06). In patients after OHCA, left ventricular systolic dysfunction was associated with the need for vasopressors, and Doppler TTE hemodynamic parameters had higher correlation coefficients compared with vasopressor requirements than LVEF. This emphasizes the complex nature of shock after OHCA, including pathophysiologic processes not captured by TTE assessment alone.

The non-invasive evaluation of heart function in patients with an acute myocardial infarction: The role of impedance cardiography.

The purpose of this study was to analyze hemodynamic changes in patients treated with percutaneous coronary intervention (PCI) at an early stage of acute myocardial infarction (AMI) and at 1-month follow-up. Patients with AMI (n = 27) who underwent PCI were analyzed using impedance cardiography (ICG). ICG data were collected continuously (beat by beat) during the whole PCI procedure and thereafter at every 60 s for the next 24 h. Blood pressure was taken every 10 min and stored for analysis. Additionally the following parameters were measured: cardiac index (CI), stroke volume index (SVi), left cardiac work index (LCWi), contractility index (CTi), ventricular ejection time (VET), systemic vascular resistance index (SVRi), thoracic fluid content index (TFCi) and heart rate (HR). In the first 24 h after PCI all the contractility parameters including CI, SVi, LCWi, CTi and VET significantly decreased, whereas HR, SVRi and TFCi increased compared to baseline. All of the parameters examined got normalized at 1 month. The CI, SVi, LCWi, CTi, SVRi did not significantly differ from baseline, however the HR and VET were significantly lower compared to first day after PCI CONCLUSIONS: Cardiac performance deteriorates early after PCI and normalizes after 1 month in patients with an AMI. ICG is useful for hemodynamic monitoring of AMI patients during and after invasive therapy.

Estimated left ventricular pressure-myocardial strain loop as an index of cardiac work predicts all-cause mortality in patients receiving regular hemodialysis.

A non-invasive method for left ventricular pressure-strain analysis has recently been introduced to provide information on cardiac work and detect subtler changes in cardiac function. This study aims to verify and construct a novel index that could accurately and independently predict the prognosis of patients with end-stage kidney disease (ESRD) receiving regular hemodialysis. Patients with end-stage kidney disease (ESRD) receiving maintenance hemodialysis (4-h sessions, 3 times weekly for 3 months or more) and who underwent echocardiography between 2009 and 2014 in China Medical University Hospital, Taichung, Taiwan, were enrolled. Conventional (left ventricular ejection fraction, LVEF) and strain echocardiography parameters (global longitudinal strain, GLS; cardiac work index, CWI) in 102 eligible patients were analyzed and compared. CWI was calculated from estimated LV pressure-myocardial strain loop area. Results show that, while no significant differences were found between LVEF (0.57 ± 0.12 vs. 0.59 ± 0.09, P = 0.27) and GLS (-16.12 ± 6.57% vs. -18.44 ± 5.54%, P = 0.07), deceased patients had significantly lower CWI (1339 ± 683.05 mmHg% vs. 1883.38 ± 640.99 mmHg%, P = 0.0002) than surviving patients. The predictive values defined by area under the curve (AUC) of LVEF, GLS and CWI were 0.499, 0.619 and 0.724, respectively. In conclusion, CWI is an accurately independent predictor of all-cause mortality in ESRD patients receiving regular hemodialysis and may superior to the current predictors such as LVEF and GLS.

Cardiac hemodynamic response to the 6-minute walk test in patients with intestinal carcinoma undergoing bevacizumab treatment.

Exercise capacity is evaluated using the 6-minute walk test (6MWT) in various cardiovascular diseases. Bevacizumab (BEV) has been associated with significant risk of cardiovascular complications. The aim of this study was to investigate BEV-related influences on cardiac hemodynamic response to 6MWT. We prospectively studied 24 patients with intestinal carcinoma to assess the hemodynamic response during 6MWT, of whom eight underwent BEV treatment. Obtained data was analyzed to identify hemodynamic differences between BEV and non-BEV treated patients. Twenty-four patients with stage IV intestinal carcinoma consented to assessment after the completion of three cycles of BEV-combined chemotherapy (age, 46.4±16.7 years) or standard chemotherapy alone (age, 56.4±13.7 years). In comparison with non-BEV treated patients, BEV-treated patients walked less (484.3±42.4 vs. 503.0±48.2, P=0.339). These two groups manifested similar hemodynamic response during the 6MWT. The change of hemodynamic parameters at 1 minute after completion of 6MWT was defined as hemodynamic parameter recovery. BEV-treated patients had significantly lower change of left cardiac work index (LCWi), cardiac index (CI), cardiac output (CO) and stroke volume (SV) after 6MWT. Interestingly, in BEV-treated patients CI change after 6MWT was predominantly related to the decrease in SV instead of heart rate (HR) as suggested by a higher standardized beta coefficient (0.883 vs. 0.657) and semi-partial correlations (0.821 vs. 0.677). Estimation of hemodynamic response to 6MWT is feasible, and may provide useful information of myocardial damage in BEV-treated patients.

Elevated plasma endocan and BOC in heart failure patients decrease after heart transplantation in association with improved hemodynamics

BackgroundThe prevalence of heart failure (HF) is rising with ageing population and constitutes a major health problem globally. A common complication of HF is pulmonary hypertension (PH) which negatively impacts survival. A pathophysiological association between HF and PH with tumorigenic processes has been suggested. We aimed to identify the plasma levels of, and the association between tumour-related proteins and hemodynamic improvements in patients with HF and PH due to left heart disease (LHD) before and 1-year after heart transplantation (HT).MethodsForty-eight tumour-related proteins were measured with proximity extension assay in plasma from 20 controls and 26 HF patients before and 1-year after HT. Patients’ hemodynamics were measured with right heart catheterization.ResultsOut of 48 proteins, specifically, plasma levels of endocan and brother of CDO (BOC) were elevated in end-stage HF patients compared to controls (p < 0.001), but decreased after HT (p < 0.01), towards controls’ levels. The decrease of endocan levels after HT correlated with improved mean pulmonary arterial pressure (rs = 0.80, p < 0.0001), pulmonary arterial wedge pressure (rs = 0.63, p = 0.0012), and pulmonary vascular resistance (rs = 0.70, p < 0.001). The decrease and normalization of BOC after HT correlated with decreased mean right atrial pressure (rs = 0.61 p = 0.0015) and NT-proBNP (rs = 0.57, p = 0.0022), as well as increased cardiac index (rs = − 0.51, p = 0.0086) and left-ventricular stroke work index (rs = − 0.57, p = 0.0039).ConclusionOur results suggest that (i) plasma endocan in HF may reflect the state of pulmonary vascular congestion and PH-LHD, whereas (ii) plasma BOC may reflect the cardiac function and the hemodynamic overload in HF. The exact role of these proteins and their clinical applicability as biomarkers in HF and PH-LHD ought to be investigated in larger cohorts.

Left ventricular myocardial work in the culprit vessel territory and impact on left ventricular remodelling in patients with ST-segment elevation myocardial infarction after primary percutaneous coronary intervention

Adverse left ventricular (LV) remodelling after ST-segment elevation myocardial infarction (STEMI) is associated with poor outcome. Global and regional LV myocardial work (LVMW) derived from speckle tracking echocardiographic strain data in combination with non-invasive blood pressure recordings could provide information for prediction of LV remodelling after STEMI. The aim of the study was to assess the predictive value of global and regional LVMW for LV remodelling before discharge in patients with STEMI. Three-hundred and fifty STEMI patients treated with primary percutaneous coronary intervention (PCI) were included [265 men (76%), mean age: 61 ± 10 years]. Clinical variables, conventional echocardiographic parameters, global and regional measures of myocardial work index (MWI), and myocardial work efficiency were recorded before discharge. The primary endpoint was early LV remodelling defined as increase in LV end-diastolic volume (LVEDV) ≥20% at 3 months after STEMI. Eighty-seven patients (25%) showed early LV remodelling. The global and regional LVMW in the culprit territory were significantly lower in patients with early LV remodelling. Peak troponin I (OR 1.109, 95% CI 1.046-1.177; P = 0.001), LVEDV (OR 0.972, 95% CI 0.959-0.984; P < 0.001) and regional MWI in the culprit vessel territory (OR 0.602, 95% CI 0.383-0.945; P = 0.027) were independently associated with early LV remodelling. In STEMI patients treated with primary PCI and optimal medical therapy, the regional cardiac work index in the culprit vessel territory before discharge is independently associated with early adverse LV remodelling.