Independent and incremental prognostic value of Doppler-derived left ventricular total isovolumic time in patients with systolic heart failure

Lung fluid content during 6MWT in patients with COPD with and without comorbid heart failure

BACKGROUND

Impact of lung fluid content changing during exercise has not been investigated in chronic obstructive pulmonary disease (COPD). Using a novel point-of-care measurement system (remote dielectric sensing (ReDS) system), we aimed to investigate changes in lung fluid content before and after 6-minute walk test (6MWT); especially, differences between patients with and without comorbid heart failure (HF) were evaluated.

METHODS

From June 2021 to July 2022, patients with COPD referred for 6MWT were prospectively enrolled. Measurements of lung fluid content by ReDS were conducted before and after 6MWT. Data on demographics, exacerbation history, spirometry and 6MWT were collected. Patients were also assessed for comorbid HF by cardiovascular evaluation. The main variables of interest were pre-6MWT ReDS, post-6MWT ReDS and post-pre ∆ReDS.

RESULTS

In total, 133 patients with COPD were included. Comparisons between patients with COPD with and without HF indicated similar pre-6MWT ReDS (26.9%±5.9% vs 26.5%±4.7%; p=0.751), but a significant difference in post-6MWT ReDS (29.7%±6.3% vs 25.7%±5.3%; p=0.002). Patients with COPD without HF exhibited a significant decrease in post-6MWT ReDS (from 26.5% to 25.7%; paired t-test p=0.001); conversely, those with HF displayed a remarkable increase in post-6MWT ReDS (from 26.9% to 29.7%; paired t-test p<0.001). Receiver operating characteristic curve analysis showed an area under the curve of 0.82 (95% CI 0.71 to 0.93) for post-pre ∆ReDS in differentiating between patients with COPD with and without HF.

CONCLUSIONS

Dynamic changes in lung fluid content prior to and following 6MWT significantly differed between patients with COPD with and without HF. Measurements of lung fluid content by ReDS during exercise testing may be of merit to identify patients with COPD with unrecognised HF.

Accelerated ageing and coronary microvascular dysfunction in chronic heart failure in Tgαq*44 mice

Age represents a major risk factor in heart failure (HF). However, the mechanisms linking ageing and HF are not clear. We aimed to identify the functional, morphological and transcriptomic changes that could be attributed to cardiac ageing in a model of slowly progressing HF in Tgαq*44 mice in reference to the cardiac ageing process in FVB mice. In FVB mice, ageing resulted in the impairment of diastolic cardiac function and in basal coronary flow (CF), perivascular and interstitial fibrosis without changes in the cardiac activity of angiotensin-converting enzyme (ACE) or aldosterone plasma concentration. In Tgαq*44 mice, HF progression was featured by the impairment of systolic and diastolic cardiac function and in basal CF that was associated with a distinct rearrangement of the capillary architecture, pronounced perivascular and interstitial fibrosis, progressive activation of cardiac ACE and systemic angiotensin-aldosterone-dependent pathways. Interestingly, cardiac ageing genes and processes were represented in Tgαq*44 mice not only in late but also in early phases of HF, as evidenced by cardiac transcriptome analysis. Thirty-four genes and 8 biological processes, identified as being ageing related, occurred early and persisted along HF progression in Tgαq*44 mice and were mostly associated with extracellular matrix remodelling and fibrosis compatible with perivascular fibrosis resulting in coronary microvascular dysfunction (CMD) in Tgαq*44 mice. In conclusion, accelerated and persistent cardiac ageing contributes to the pathophysiology of chronic HF in Tgαq*44 mice. In particular, prominent perivascular fibrosis of microcirculation resulting in CMD represents an accelerated cardiac ageing phenotype that requires targeted treatment in chronic HF.

Right Ventricular Diastolic Performance in Patients With Chronic Thromboembolic Pulmonary Hypertension Assessed by Echocardiography

Background: There have been no systemic studies about right heart filling pressure and right ventricular (RV) distensibility in patients with chronic thromboembolic pulmonary hypertension (CTEPH). Therefore, we aimed to explore combinations of echocardiographic indices to assess the stages of RV diastolic dysfunction.

Methods and Results: We recruited 32 healthy volunteers and 71 patients with CTEPH. All participants underwent echocardiography, cardiac catheterization (in patients with CTEPH), and a 6-min walk test (6MWT). The right atrial (RA) end-systolic area was adjusted for body surface area (BSA) (indexed RA area). RV global longitudinal diastolic strain rates (SRs) and RV ejection fraction (EF) were measured by speckle tracking and three-dimensional echocardiography (3D echo), respectively. All 71 patients with CTEPH underwent pulmonary endarterectomy. Of the 71 patients, 52 (73%) had decreased RV systolic function; 12 (16.9%), 26 (36.6%), and 33 (46.5%) patients had normal RV diastolic pattern, abnormal relaxation (stage 1), and pseudo-normal patterns (stage 2), respectively. The receiver operating characteristic curve analysis showed that the optimal cut-off values of early diastolic SR <0.8 s⁻¹ and indexed RA area > 8.8 cm²/BSA had the best accuracy in identifying patients with RV diastolic dysfunction, with 87% sensitivity and 82% specificity. During a mean follow-up of 25.2 months after pulmonary endarterectomy, the preoperative indexed RA area was shown as an independent risk factor of the decreased 6MWT distance.

Conclusions: Measuring early diastolic SR and indexed RA area would be useful in stratifying RV diastolic function.

Signs of diastolic dysfunction are graded by serum testosterone levels in aging C57BL/6 male mice

We investigated whether maladaptive, age-associated changes in heart structure and function were linked to circulating testosterone levels. Male C57BL/6 mice had a gonadectomy (GDX) or sham surgery at 4 weeks and effects of GDX on the heart were examined with echocardiography. Serum testosterone was measured with ELISA. Left ventricular (LV) mass increased with age but was smaller in GDX mice than sham at 18 months (144.0 ± 8.7 vs 118.2 ± 11.9 mg; p = 0.009). The isovolumic relaxation time (IVRT) declined with age but was prolonged in GDX mice at 18 months (10.5 ± 0.8 vs 12.5 ± 0.5 msec, p = 0.008). Ejection fraction did not change with age or GDX, but E/A ratios were lower in GDX mice than controls at 18 months (1.6 ± 0.2 vs 1.3 ± 0.1, p = 0.021). When links between serum testosterone and cardiac parameters were examined longitudinally in 18-24-month-old mice, LV mass declined with decreasing testosterone (β = 37.70, p = 0.016), however IVRT increased as testosterone decreased (β=-2.69, p = 0.036). Since longer IVRT and lower E/A ratios are signs of diastolic dysfunction, low circulating testosterone may promote or exacerbate diastolic dysfunction in older males. These findings suggest that lower testosterone directly modifies heart structure and function to promote maladaptive remodeling and diastolic dysfunction in the aging heart.

6-minute walking test: a useful tool in the management of heart failure patients

Reduced functional ability and exercise tolerance in patients with heart failure (HF) are associated with poor quality of life and a worse prognosis. The 6-minute walking test (6MWT) is a widely available and well-tolerated test for the assessment of the functional capacity of patients with HF. Although the cardiopulmonary exercise test (a maximal exercise test) remains the gold standard for the evaluation of exercise capacity in patients with HF, the 6MWT (submaximal exercise test) may provide reliable information about the patient’s daily activity. The current review summarizes the value of 6MWT in patients with HF and identifies its usefulness and limitations in everyday clinical practice in populations of HF. We aimed to investigate potential associations of 6MWD with other measures of functional status and determinants of 6MWD in patients with HF as well as to review its prognostic role and changes to various interventions in these patients.

Right ventricular total isovolumic time: Reference value study

BACKGROUND

There is lack of noninvasive indices to detail the right side cardiovascular physiology. Total isovolumic time (tIVT) is a sensitive marker of left ventricular electromechanical efficiency and systolic-diastolic interaction. The aim of the study was to evaluate normal reference value of the right ventricular tIVT with increasing age.

METHODS AND RESULTS

One hundred and eighty-one healthy volunteers (51% male) underwent transthoracic echocardiography. The population was divided into four categories according to age: A < 30 years; B 30-39 years; C 40-49 years; and C ≥ 50 years old. tIVT was computed in seconds/minutes as: 60 - (tET + tFT). tET and tFT are the total ejection and filling time adjusted by the heart rate, measured, respectively, from the onset to the end of the right ventricle (RV) forward flow through the pulmonary valve and from the onset of the E-wave and the end of the A-wave at the level of the tricuspid valve. The mean RV tIVT was 7 ± 1.1 s/min and increased significantly with age, from a 3.4 to 9.7 s/min(P < 0.0001). Significant correlation was found between tIVT and trans-tricuspid E/E' (P < 0.0001; 0.78 (95% CI: 0.715-0.831) while weaker between tIVT and E/A (P = 0.001; -0.283 95% CI: -0.413 to -0.143).

CONCLUSION

The normal values of RV tIVT increase with age and correlate significantly with Doppler diastolic parameters.

The impact of age on cardiac electromechanical function in asymptomatic individuals

BACKGROUND AND AIM

Whether aging affects left ventricular (LV) filling and ejection and the LV electric function is not well established. We investigated the effect of normal aging on echocardiographic measurements of LV morphology and function, LV electric function and the relationship between LV electric and mechanical function in asymptomatic individuals.

METHODS

As part of a cross-sectional survey for the prevalence of coronary risk factors in the general population in Caltanissetta, Italy, individuals without signs or symptoms of coronary artery disease or heart failure were randomly selected and underwent electrocardiographic and echocardiographic examination. QRS duration and amplitude, PR, QT and QTc intervals, were automatically measured. Echocardiographic examination included the measurement of LV systolic and diastolic dimensions, volumes and ejection fraction (EF). From the spectral Doppler flow LV early diastolic (E wave) and atrial systolic (A wave) velocities, isovolumic relaxation time (IVRT) and isovolumic contraction time (IVCT) were measured. Global LV dyssynchrony was assessed using the total isovolumic time (T-IVT) and the Tei index.

RESULTS

Aging reduced LV long-axis function, LV filling time and E wave velocity and prolonged T-IVT, IVRT and Tei index. It did not affect LV dimensions, ejection fraction, IVCT or QRS amplitude and duration. QRS duration correlated with LV dimensions, wall thickness and left atrial area. QRS amplitude and QTc interval correlated with the markers of LV dyssynchrony T-IVT and Tei index.

CONCLUSIONS

Overall, systolic and electric LV function are not affected by age, whereas subendocardial function, diastolic and synchronous function are significantly influenced.

Quality of life questionnaire predicts poor exercise capacity only in HFpEF and not in HFrEF

BACKGROUND

The Minnesota Living with Heart Failure Questionnaire (MLHFQ) is the most widely used measure of quality of life (QoL) in HF patients. This prospective study aimed to assess the relationship between QoL and exercise capacity in HF patients.

METHODS

The study subjects were 118 consecutive patients with chronic HF (62 ± 10 years, 57 females, in NYHA I-III). Patients answered a MLHFQ questionnaire in the same day of complete clinical, biochemical and echocardiographic assessment. They also underwent a 5 min walk test (6-MWT), in the same day, which grouped them into; Group I: ≤ 300 m and Group II: >300 m. In addition, left ventricular (LV) ejection fraction (EF), divided them into: Group A, with preserved EF (HFpEF) and Group B with reduced EF (HFrEF).

RESULTS

The mean MLHFQ total scale score was 48 (±17). The total scale, and the physical and emotional functional MLHFQ scores did not differ between HFpEF and HFpEF. Group I patients were older (p = 0.003), had higher NYHA functional class (p = 0.002), faster baseline heart rate (p = 0.006), higher prevalence of smoking (p = 0.015), higher global, physical and emotional MLHFQ scores (p < 0.001, for all), larger left atrial (LA) diameter (p = 0.001), shorter LV filling time (p = 0.027), higher E/e' ratio (0.02), shorter isovolumic relaxation time (p = 0.028), lower septal a' (p = 0.019) and s' (p = 0.023), compared to Group II. Independent predictors of 6-MWT distance for the group as a whole were increased MLHFQ total score (p = 0.005), older age (p = 0.035), and diabetes (p = 0.045), in HFpEF were total MLHFQ (p = 0.007) and diabetes (p = 0.045) but in HFrEF were only LA enlargement (p = 0.005) and age (p = 0.013. A total MLHFQ score of 48.5 had a sensitivity of 67% and specificity of 63% (AUC on ROC analysis of 72%) for limited exercise performance in HF patients.

CONCLUSIONS

Quality of life, assessment by MLHFQ, is the best correlate of exercise capacity measured by 6-MWT, particularly in HFpEF patients. Despite worse ejection fraction in HFrEF, signs of raised LA pressure independently determine exercise capacity in these patients.

Right and left heart dysfunction predict mortality in pulmonary hypertension

In pulmonary hypertension (PH), the right heart dysfunction is a strong predictor of adverse clinical outcome, while the role of the left heart is not fully determined. The aim of this study was to identify predictors of mortality in precapillary PH including measures of both right and left heart function. We studied 34 patients (mean age 64 ± 13, range 31-82 years, 24 females) with precapillary PH, all of whom underwent detailed Doppler echocardiographic examination of the right and left heart function using conventional and speckle-tracking echocardiography. Patients were followed up for up to 8 years (mean 4·2 ± 1·9 years). At follow-up, 16 patients survived. Left ventricular (LV) filling time (P = 0·007), pulmonary artery acceleration time (P = 0·009), right atrial pressure (RAP) (P<0·001) and tricuspid regurgitation (TR) severity (P = 0·007) were worse in the deceased group. RV global longitudinal strain (GLS) (P = 0·001), RAP (P≤0·001), LV filling time (P<0·001) and TR severity (P<0·001) were the most accurate predictors, having the largest AUC (>0·65) and carried the highest risk for mortality (P<0·001 for all). The strongest predictors of mortality in precapillary PH indirectly reflect both left and right heart dysfunction including atrial structure and function disturbances. While an interaction pattern is observed, it needs to be confirmed in a larger cohort.

BNP and NT-proBNP as prognostic markers in persons with chronic stable heart failure

Prognosis permits clinicians to separate persons with heart failure (HF) into subgroups based on likely health outcomes. Treatment is partly guided by these likely outcomes. This systematic review explores whether brain natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) are independent predictors of prognosis in persons with chronic stable HF. We electronically searched Medline, Embase, AMED, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and CINAHL for English-language articles published between 1989 and mid-2012. We utilized trained reviewers and standardized forms to screen articles for inclusion and extracted data from included articles. All included studies were summarized in narrative and tabular form. We used the Hayden criteria to assess the risk of bias. Sixteen BNP publications and 88 NT-proBNP publications were included in the systematic review. BNP was positively associated with all-cause and HF mortality. NT-proBNP was positively associated with all-cause and cardiovascular mortality. BNP and NT-proBNP levels are useful for estimating prognosis in persons with chronic stable HF. Further research is required to establish optimal cutpoints and to assess whether prognostic effects differ by age, sex, or time period.

Left atrial emptying fraction predicts limited exercise performance in heart failure patients

AIM

We aimed in this study to assess the role of left atrial (LA), in addition to left ventricular (LV) indices, in predicting exercise capacity in patients with heart failure (HF).

METHODS

This study included 88 consecutive patients (60 ± 10 years) with stable HF. LV end-diastolic and end-systolic dimensions, ejection fraction (EF), mitral and tricuspid annulus peak systolic excursion (MAPSE and TAPSE), myocardial velocities (s', e' and a'), LA dimensions, LA volume and LA emptying fraction were measured. A 6-min walking test (6-MWT) distance was performed on the same day of the echocardiographic examination.

RESULTS

Patients with limited exercise performance (≤ 300 m) were older (p = 0.01), had higher NYHA functional class (p = 0.004), higher LV mass index (p = 0.003), larger LA (p = 0.002), lower LV EF (p = 0.009), larger LV end-systolic dimension (p = 0.007), higher E/A ratio (p = 0.03), reduced septal MAPSE (p < 0.001), larger LA end-systolic volume (p = 0.03), larger LA end-diastolic volume (p = 0.005) and lower LA emptying fraction (p < 0.001) compared with good performance patients. In multivariate analysis, only the LA emptying fraction [0.944 (0.898-0.993), p = 0.025] independently predicted poor exercise performance. An LA emptying fraction < 60% was 68% sensitive and 73% specific (AUC 0.73, p < 0.001) in predicting poor exercise performance.

CONCLUSION

In heart failure patients, the impaired LA emptying function is the best predictor of poor exercise capacity. This finding highlights the need for routine LA size and function monitoring for better optimization of medical therapy in HF.

Gender related predictors of limited exercise capacity in heart failure

AIM

The aim of this study was to investigate the impact of gender on the prediction of limited exercise capacity in heart failure (HF) patients assessed by 6 minute walk test (6-MWT).

METHODS

In 147 HF patients (mean age 61 ± 11 years, 50.3% male), a 6-MWT and a Doppler echocardiographic study were performed in the same day. Conventional cardiac measurements were obtained and global LV dyssynchrony was indirectly assessed using total isovolumic time - t-IVT [in s/min; calculated as: 60 - (total ejection time - total filling time)] and Tei index (t-IVT/ejection time). Patients were divided into two groups according to gender, which were again divided into two subgroups based on the 6-MWT distance (Group I: ≤ 300 m, and Group II: > 300 m).

RESULTS

Female patients were younger (p = 0.02), and had higher left ventricular (LV) ejection fraction - EF (p = 0.007) but with similar 6-MWT distance to male patients (p = 68). Group I male patients had lower hemoglobin level (p = 0.02) and lower EF (p = 0.03), compared with Group II, but none of the clinical or echocardiographic variables differed between groups in female patients. In multivariate analysis, only t-IVT [0.699 (0.552-0.886), p = 0.003], and LV EF [0.908 (0.835-0.987), p = 0.02] in males, and NYHA functional class [4.439 (2.213-16.24), p = 0.02] in females independently predicted poor 6-MWT distance (< 300 m).

CONCLUSION

Despite similar limited exercise capacity, gender determines the pattern of underlying cardiac disturbances; ventricular dysfunction in males and subjective NYHA class in female heart failure patients.

Left ventricular markers of global dyssynchrony predict limited exercise capacity in heart failure, but not in patients with preserved ejection fraction

BACKGROUND

The aim of this study was to prospectively examine echocardiographic parameters that correlate and predict functional capacity assessed by 6 min walk test (6-MWT) in patients with heart failure (HF), irrespective of ejection fraction (EF).

METHODS

In 147 HF patients (mean age 61 ± 11 years, 50.3% male), a 6-MWT and an echo-Doppler study were performed in the same day. Global LV dyssynchrony was indirectly assessed by total isovolumic time - t-IVT [in s/min; calculated as: 60 - (total ejection time + total filling time)], and Tei index (t-IVT/ejection time). Patients were divided into two groups based on the 6-MWT distance (Group I: ≤ 300 m and Group II: >300 m), and also in two groups according to EF (Group A: LVEF ≥ 45% and Group B: LVEF < 45%).

RESULTS

In the cohort of patients as a whole, the 6-MWT correlated with t-IVT (r = -0.49, p < 0.001) and Tei index (r = -0.43, p < 0.001) but not with any of the other clinical or echocardiographic parameters. Group I had lower hemoglobin level (p = 0.02), lower EF (p = 0.003), larger left atrium (p = 0.02), thicker interventricular septum (p = 0.02), lower A wave (p = 0.01) and lateral wall late diastolic myocardial velocity a' (p = 0.047), longer isovolumic relaxation time (r = 0.003) and longer t-IVT (p = 0.03), compared with Group II. In the patients cohort as a whole, only t-IVT ratio [1.257 (1.071-1.476), p = 0.005], LV EF [0.947 (0.903-0.993), p = 0.02], and E/A ratio [0.553 (0.315-0.972), p = 0.04] independently predicted poor 6-MWT performance (<300 m) in multivariate analysis. None of the echocardiographic measurements predicted exercise tolerance in HFpEF.

CONCLUSION

In patients with HF, the limited exercise capacity, assessed by 6-MWT, is related mostly to severity of global LV dyssynchrony, more than EF or raised filling pressures. The lack of exercise predictors in HFpEF reflects its multifactorial pathophysiology.

Independent and incremental value of severely enlarged left atrium in risk stratification of very elderly patients with chronic systolic heart failure

The authors sought to assess the impact on survival of demographic, clinical, and echo-Doppler parameters in patients with chronic heart failure due to left ventricular systolic dysfunction divided according to age groups. This study included 734 patients (age 69±11 years) who were classified into tertiles of age: I (22-66 years), II (67-76 years), and III (77-94 years). Severely enlarged left atrial size was defined as ≥52 mm in men and ≥47 mm in women. Multivariable analysis identified male sex (P=.018) and severely enlarged left atrium (P=.024) as significant correlates of all-cause mortality in the very elderly cohort, while restrictive filling pattern (RFP) (P=.004) and New York Heart Association class III or IV (P=.005) among patients of the first tertile and RFP (P=.028) among patients in the second tertile were independently associated with mortality after 30±21 months of follow-up. At the interactive stepwise model in the very elderly population, a severely enlarged left atrium, added to the model after clinical parameters and ejection fraction, moved the chi-square value from 20.7 to 25.8 (P=.048). RFP emerged as the single best predictor of all-cause mortality in the younger and intermediate ranges, whereas severely enlarged left atrium was the best predictor in the very elderly.