Systolic and Diastolic Dyssynchrony in Patients With Diastolic Heart Failure and the Effect of Medical Therapy

Effects of postsystolic shortening and diastolic dyssynchrony on myocardial work in untreated early hypertension patients

OBJECTIVES

Myocardial work is estimated from noninvasive pressure-strain loop for advanced assessment of left ventricular function. Postsystolic shortening and diastolic dyssynchrony of left ventricle were noted early in hypertension. Their novel effects on myocardial work will be illustrated in this study.

METHODS

We recruited 43 newly diagnosed hypertensive patients (mean age 51.3 ± 12.5 years, 55.8% men) and 32 age-matched and sex-matched healthy individuals (mean age 52.7 ± 10.5 years, 37.5% men) as control. Pressure-strain loop derived myocardial work incorporated global longitudinal strain from speckle tracking echocardiography with brachial artery cuff pressure. Postsystolic strain index (PSI) was defined by the percentage of postsystolic shortening over peak strain. Diastolic dyssynchrony was assessed by standard deviation of time to peak early diastolic strain rate (TDSr-SD) of 18 segments, and maximal difference of time to peak early diastolic strain rate (TDSr-MD) between any two segments.

RESULTS

After multivariate regression analysis, global myocardial work index (GWI) was independently correlated with TDSr-SD (B = -0.498, P = 0.001) and TDSr-MD (B = -0.513, P = 0.001). Global myocardial constructive work (GCW) was independently correlated with TDSr-SD (B = -0.334, P = 0.025) and TDSr-MD (B = -0.397, P = 0.007). Global myocardial wasted work (GWW) was independently correlated with PSI (B = 0.358, P = 0.019). Global myocardial work efficiency (GWE) was lower in hypertensive patients than healthy control (P = 0.001). The untreated hypertensive patients were different from the healthy individuals with higher TDSr-SD, TDSr-MD, GWI, GCW, GWW, and PSI (all P < 0.05).

CONCLUSION

In conclusion, the effect of diastolic dyssynchrony mainly influenced constructive work, whereas postsystolic shortening affected wasted work in early untreated hypertension.

Longitudinal evaluation of diastolic dyssynchrony by SPECT gated myocardial perfusion imaging early after acute myocardial infarction and the relationship with left ventricular remodeling progression in a swine model

BACKGROUND

Left ventricular diastolic dyssynchrony (LVDD), a dyssynchronous relaxation pattern, has been known to develop after myocardial damage. We aimed to evaluate the dynamic changes in LVDD in the early stage of acute myocardial infarction (AMI) by phase analysis of 99mtechnetium methoxyisobutylisonitrile (99mTc-MIBI) single-photon emission computed tomography (SPECT) gated myocardial perfusion imaging (GMPI) and explore its relationship with the progression of left ventricular remodeling (LVR).

METHODS

The left anterior descending coronary arteries of 16 Bama miniature swine were occluded with a balloon to build AMI models. Animals were imaged by SPECT GMPI before AMI and at 1 day, 1 week and 4 weeks after AMI, and quantitative analysis was performed to determine the extent of left ventricle (LV) perfusion defects, left ventricular systolic dyssynchrony (LVSD) and the LVDD parameters: phase histogram bandwidth (PBW) and phase standard deviation (PSD). Echocardiography was simultaneously applied to evaluate left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), left ventricular ejection fraction (LVEF), and the LVDD parameters: Te-12-diff and Te-12-SD. Myocardial injury markers were measured, and 12-lead ECGs were performed. The degree of LVR progression was defined as ΔLVESV (%) = (LVESVAMI4weeks - LVESVAMI1day)/LVESVAMI1day.

RESULTS

Thirteen swine completed the study. LVDD parameters changed dynamically at different time points after AMI. LVDD occurred as early as 1 day after AMI, peaked at 1 week, and trended toward a partial recovery at 4 weeks. Phase analysis on SPECT GMPI showed a significant correlation with tissue Doppler imaging for the assessment of LVDD during the longitudinal evaluation (r = 0.569 to 0.787, both P <0.05). During the univariate and multivariate regression analyses, the LVDD parameters PBW and PSD as of 1 day after AMI were significantly associated with the progression of LVR, respectively (PBW, β = 0.004, 95% CI 0.001 to 0.007, P = 0.024; PSD, β = 0.008, 95% CI 0.000 to 0.017, P = 0.049). Adjusted smooth curve fitting and threshold effect analysis indicated PBW and PSD break-point values of 142° and 60.4°, respectively, to predict the progression of LVR after AMI.

CONCLUSIONS

Phase analysis of SPECT GMPI can accurately and reliably characterize LVDD. LVDD occurred on the first day after AMI, reached its peak at 1 week, and partially recovered at 4 weeks after AMI. LVDD as evaluated by phase analysis of SPECT GMPI early after AMI was significantly associated with the progression of LVR. The early assessment of LVDD after AMI may provide helpful information for predicting the progression of LVR in the future.

Assessment of left ventricular dyssynchrony by speckle tracking echocardiography in children with duchenne muscular dystrophy

Prognosis of Duchenne muscular dystrophy (DMD) is related to cardiac dysfunction. Two dimensional-speckle tracking echocardiography (2D-STE) has recently emerged as a non-invasive functional biomarker for early detection of DMD-related cardiomyopathy. This study aimed to determine, in DMD children, the existence of left ventricle (LV) dyssynchrony using 2D-STE analysis. This prospective controlled study enrolled 25 boys with DMD (mean age 11.0 ± 3.5 years) with normal LV ejection fraction and 50 age-matched controls. Three measures were performed to assess LV mechanical dyssynchrony: the opposing-wall delays (longitudinal and radial analyses), the modified Yu index, and the time-to-peak delays of each segment. Feasibility and reproducibility of 2D-STE dyssynchrony were evaluated. All three mechanical dyssynchrony criteria were significantly higher in the DMD group than in healthy subjects: (1) opposing-wall delays in basal inferoseptal to basal anterolateral segments (61.4 ± 45.3 ms vs. 18.3 ± 50.4 ms, P < 0.001, respectively) and in mid inferoseptal to mid anterolateral segments (58.6 ± 35.3 ms vs. 42.4 ± 36.4 ms, P < 0.05, respectively), (2) modified Yu index (33.3 ± 10.1 ms vs. 28.5 ± 8.1 ms, P < 0.05, respectively), and (3) most of time-to-peak values, especially in basal and mid anterolateral segments. Feasibility was excellent and reliability was moderate to excellent, with ICC values ranging from 0.49 to 0.97. Detection of LV mechanical dyssynchrony using 2D-STE analysis is an easily and reproducible method in paediatric DMD. The existence of an early LV mechanical dyssynchrony visualized using 2D-STE analysis in children with DMD before the onset of cardiomyopathy represents a perspective for future paediatric drug trials in the DMD-related cardiomyopathy prevention.Clinical Trial Registration Clinicaltrials.gov NCT02418338. Post-hoc study, registered on April 16, 2015.

Mechanical dyssynchrony: How do we measure it, what it means, and what we can do about it

Left ventricular mechanical dyssynchrony (LVMD) is defined by a difference in the timing of mechanical contraction or relaxation between different segments of the left ventricle (LV). Mechanical dyssynchrony is distinct from electrical dyssynchrony as measured by QRS duration and has been of increasing interest due to its association with worse prognosis and potential role in patient selection for cardiac resynchronization therapy (CRT). Although echocardiography is the most used modality to assess LVMD, some limitations apply to this modality. Compared to echo-based modalities, nuclear imaging by gated single-photon emission computed tomography (GSPECT) myocardial perfusion imaging (MPI) has clear advantages in evaluating systolic and diastolic LVMD. GSPECT MPI can determine systolic and diastolic mechanical dyssynchrony by the variability in the timing in which different LV segments contract or relax, which has prognostic impact in patients with coronary artery disease and heart failure. As such, by targeting mechanical dyssynchrony instead of electrical dyssynchrony, GSPECT MPI can potentially improve patient selection for CRT. So far, few studies have investigated the role of diastolic dyssynchrony, but recent evidence seems to suggest high prevalence and more prognostic impact than previously recognized. In the present review, we provide an oversight of mechanical dyssynchrony.

Poorer Exercise Accommodation of Regional Systolic Myocardial Motion after Spironolactone Treatment in Heart Failure Patients with Preserved Ejection Fraction and Ventricular Dyssynchrony

Patients with heart failure and preserved ejection fraction (HFpEF) are known to have reduced systolic myocardial velocity (Sm) with impaired accommodation to exercise. We tested the impact of an aldosterone antagonist on Sm at rest and post-exercise. Forty-nine HFpEF patients (65 ± 11 years, 24 male) with HF signs/symptoms, mitral E/Ea (annular early diastolic velocity) > 8, and left ventricular (LV) EF > 50% were randomized to spironolactone (25 mg/day, 25 patients) or the Control. At baseline and 6 months, we analyzed Sm of basal LV segments at rest and after a 6 min treadmill exercise. At 6 months, post-exercise mean Sm in the spironolactone group became greater than that in the Control (9.2 ± 1.6 vs. 8.3 ± 1.0 cm/s, p = 0.021), mainly due to the increment of post-exercise % increase of lateral Sm (44 ± 30 vs. 30 ± 19% at baseline, p = 0.045). Further analyses showed the presence of systolic dyssynchrony (standard deviation of electromechanical delay of 6-basal LV segments > 35 ms) was independently associated with a poorer response to spironolactone, defined as a post-exercise % increase of lateral Sm < 50% (OR = 2.7, 95% CI = 1.8–4.2) and the increment of Ea < 1.5 cm/s (OR = 1.5, 95% CI = 1.1–2.3). Spironolactone could improve exercise accommodation of regional systolic myocardial velocity for HFpEF patients. However, its benefits could be decreased in those with ventricular dyssynchrony. This suggested possible therapeutic impacts from underlying heterogeneity within HFpEF patients.

Left ventricular dyssynchrony assessment using tissue synchronization imaging in acute myocardial infarction

Objectives:

To assess left ventricular (LV) dyssynchrony in patients with ST elevation myocardial infarction (STEMI).

Background:

Mechanical synchronization disorder leads to a decrease in LV ejection fraction (LVEF) and stroke volume, an abnormal distribution of wall tension, and increase in workload during cardiac contraction.

Methods:

We enrolled 56 participants, 36 with acute STEMI and 20 healthy controls. The automatically color-coded time to peak myocardial velocity was measured using a 6mm sample volume, manually positioned within the two-dimensional-tissue strain image of the 12 basal and middle LV segments.

Results:

A significant delay was found between the septal-lateral and septal-posterior walls in patients with STEMI compared to patients in the control group (36.36 vs. −6.0ms, P = 0.036; and 42.7 vs. 23.94ms, P = 0.042, respectively). Furthermore, all segment maximum differences and all segment standard deviation (SD; dyssynchrony index) were found to be significantly higher in the STEMI group (131.28 vs. 95.45ms, P = 0.013; and 44.47 vs. 26.45ms, P = 0.001, respectively). A significant delay between the septal-lateral walls and septal-posterior walls, all segment maximum difference, and all segment SD (dyssynchrony index) were found in patients with complicated STEMI (70.89 vs. 15.83ms, P = 0.038; 57.44 vs. 19.06ms, P = 0.040; 138.11 vs. 100.0ms, P = 0.035; and 45.44 vs. 32.50ms, P = 0.021, respectively). There was a significant negative correlation between tissue synchronization imaging parameters and LVEF, and a positive correlation with LV end systolic dimension.

Conclusion:

Patients with acute STEMI showed significant LV dyssynchrony, which was an independent predictor of inhospital complications.

Diastolic dyssynchrony assessment by gated myocardial perfusion-SPECT in subjects who underwent cardiac resynchronization therapy

BACKGROUND

Left ventricular diastolic dyssynchrony (LVDD) can be assessed by gated myocardial perfusion single-photon emission computed tomography (GMP-SPECT). LVDD is an area of interest in subjects who underwent cardiac resynchronization therapy (CRT). The aim of this post hoc analysis was to assess the role of LVDD in subjects with CRT who were followed up at 6-month period.

MATERIAL & METHODS

Left ventricular diastolic dyssynchrony was assessed by GMP-SPECT at baseline and after CRT procedure in 160 subjects from 10 different cardiological centers. CRT procedure was performed as per current guidelines. Outcomes were defined as improvement in ≥1 New York Heart Association (NYHA) class, left ventricular ejection fraction (LVEF) by 5%, and reduction in end-systolic volume (ESV) by 15% and 5% points in Minnesota Living with Heart Failure Questionnaire. LVDD was defined as diastolic phase standard deviation ≥40 ± 14°.

RESULTS

Improvement in NYHA functional class occurred in 105 (65.6%), LVEF in 74 (46.3%), decrease in ESV in 86 (53.8%), and Minnesota score in 85 (53.1%) cases. Baseline LV diastolic standard deviation was 53.53° ± 20.85 and at follow-up 40.44° ± 26.1283; (P < 0.001). LVDD was not associated with improvement in clinical outcomes at follow-up.

CONCLUSION

CRT improves both systolic and diastolic dyssynchrony values at 6-month follow-up. LVDD at baseline is correlated with cardiac functionality at follow-up, but not with overall favorable clinical outcomes.

Left ventricular systolic and diastolic dyssynchrony to improve cardiac resynchronization therapy response in heart failure patients with dilated cardiomyopathy

BACKGROUND

The systolic and diastolic dyssynchrony is physiologically related, but measure different left ventricular mechanisms. Left ventricular systolic mechanical dyssynchrony (systolic LVMD) has shown significant clinical values in improving cardiac resynchronization therapy (CRT) response in the heart failure patients with dilated cardiomyopathy (DCM). Our recent study demonstrated that LV diastolic dyssynchrony (diastolic LVMD) parameters have important prognostic values for DCM patients. However, there are a limited number of studies about the clinical value of diastolic LVMD for CRT. This study aims to explore the predictive values of both systolic LVMD and diastolic LVMD for CRT in DCM patients.

METHODS

Eighty-four consecutive CRT patients with both DCM and complete left bundle branch block (CLBBB) who received gated resting SPECT MPI at baseline were included in the present study. The phase analysis technique was applied on resting gated short-axis SPECT MPI images to measure systolic LVMD and diastolic LVMD, characterized by phase standard deviation (PSD) and phase histogram bandwidth (PBW). CRT response was defined as ≥ 5% improvement of LVEF at 6-month follow-up. Variables with P < 0.10 in the univariate analysis were included in the multivariate cox analysis.

RESULTS

During the follow-up period, 59.5% (50 of 84) patients were CRT responders. The univariate cox regression analysis showed that at baseline QRS duration, non-sustained ventricular tachycardia (NS-VT), systolic PSD, systolic PBW, diastolic PSD, diastolic PBW, scar burden and LV lead in the scarred myocardium were statistically significantly associated with CRT response. The multivariate cox regression analysis showed that QRS duration, NS-VT, systolic PSD, systolic PBW, diastolic PSD, and diastolic PBW were independent predictive factors for CRT response. Furthermore, the rate of CRT response was 94.4% (17 of 18) in patients whose LV lead was in the segments with both the first three late contraction and the first three late relaxation; by contrast, the rate of CRT response was only 6.7% (1 of 15, P < 0.000) in patients whose LV lead was in the segments with neither the first three late contraction nor the first three late relaxation.

CONCLUSION

Both systolic LVMD and diastolic LVMD from gated SPECT MPI have important predictive values for CRT response in DCM patients. Pacing at LV segments with both late contraction and late relaxation has potential to increase the CRT response.

Are SPECT MPI measures of dyssynchrony dyssynchronous?

BACKGROUND

Assessment of left ventricular mechanical dyssynchrony (LVMD) from gated SPECT myocardial perfusion imaging (MPI) aims to aid selection of patients for cardiac resynchronization therapy (CRT), using either the standard deviation of left ventricular phase (PSD) ≥ 43° or phase histogram bandwidth (HBW) of > 38° and > 30.6° in males and females, respectively. We observed dyssynchrony parameters might be affected by test type and alignment.

METHODS

We reviewed 242 patients who underwent gated SPECT MPI with use of the Emory Cardiac Toolbox comparing PSD and HBW at rest and stress for Pearson correlation, and substitutability with Bland-Altman analysis.

RESULTS

There is statistically significant difference in the mean PSD and HBW during rest vs stress (33.4 ± 17.4° vs 20.7 ± 13.5° and 97.7 ± 59.6° vs 59.4 ± 45.4°, respectively, P < 0.001). Proper valve plane alignment rendered smaller values (i.e., less dyssynchrony) in both phase SD and HBW (16.8 ± 13.5) vs (22.2 ± 14.7) (P = 0.011), and (47.0 ± 38.2) vs (60.7 ± 48.0) (P = 0.023), respectively.

CONCLUSION

Proper alignment and test type, particularly low-dose rest vs high-dose stress, should be considered when assessing LVMD using SPECT MPI.

Prognostic value of left ventricular mechanical dyssynchrony indices in long-standing type II diabetes mellitus with normal perfusion and left ventricular systolic functions on SPECT-MPI

OBJECTIVE

To test whether phase analysis indices from SPECT-MPI for left ventricular mechanical dyssynchrony (LVMD) are predictors of major adverse cardiac events (MACEs) in long-standing diabetes mellitus (DM).

METHODS

A total of 136 DM patients with normal perfusion and left ventricular systolic functions were followed up for about two years and divided into two groups according to the presence and the absence of MACEs.

RESULT

Thirteen (9.5%) patients experienced MACEs during follow-up. Patients experiencing MACEs showed significantly higher phase standard deviation (PSD) and wider phase bandwidth (PBW) than those who did not. Moreover, both PSD and PBW showed significant correlations (r = 0.25 and 0.27; P < 0.05) with duration of DM. Logistic regression analysis revealed significant associations of DM duration, microvascular complications, and LVMD indices for predicting MACEs. Kaplan-Meier event-free survival analysis revealed significantly higher rate of MACEs (Logrank = 10.02; P = 0.001) in patients with high PSD and wide PBW. An overall fit model consisting of high-PSD and wide-PBW group was improved with the addition of microvascular complications (χ2 = 15.9; P = 0.03) and further by addition of DM duration of ≥ 15 years (χ2 = 24.3; P = 0.007) as variables.

CONCLUSION

LVMD indices are novel prognostic markers in diabetic patients with normal perfusion and left ventricular systolic functions and their increases in magnitudes with DM-duration and in the presence of microvascular complications.

The prognostic value of diastolic and systolic mechanical left ventricular dyssynchrony among patients with coronary artery disease and heart failure

BACKGROUND

Prevalence and prognostic value of diastolic and systolic dyssynchrony in patients with coronary artery disease (CAD) + heart failure (HF) or CAD alone are not well understood.

METHODS

We included patients with gated single-photon emission computed tomography (GSPECT) myocardial perfusion imaging (MPI) between 2003 and 2009. Patients had at least one major epicardial obstruction ≥ 50%. We assessed the association between dyssynchrony and outcomes, including all-cause and cardiovascular death.

RESULTS

Of the 1294 patients, HF was present in 25%. Median follow-up was 6.7 years (IQR 4.9-9.3) years with 537 recorded deaths. Patients with CAD + HF had a higher incidence of dyssynchrony than patients with CAD alone (diastolic BW 28.8% for the HF + CAD vs 14.7% for the CAD alone). Patients with CAD + HF had a lower survival than CAD alone at 10 years (33%; 95% CI 27-40 vs 59; 95% CI 55-62, P < 0.0001). With one exception, HF was found to have no statistically significant interaction with dyssynchrony measures in unadjusted and adjusted survival models.

CONCLUSIONS

Patients with CAD + HF have a high prevalence of mechanical dyssynchrony as measured by GSPECT MPI, and a higher mortality than CAD alone. However, clinical outcomes associated with mechanical dyssynchrony did not differ in patients with and without HF.

Prognostic value of left-ventricular systolic and diastolic dyssynchrony measured from gated SPECT MPI in patients with dilated cardiomyopathy

BACKGROUND

Left-ventricular systolic dyssynchrony (LVSD) has been an important prognostic factor in the patients with dilated cardiomyopathy (DCM). However, the association between the LV diastolic dyssynchrony (LVDD) and clinical outcome is not well established. This study aims to evaluate the prognostic values of both systolic and diastolic dyssynchrony in patients with DCM.

METHODS

Fifty-two patients with DCM were enrolled and divided into two groups according to cardiac deaths from the follow-up data. The phase-analysis technique was applied on resting gated short-axis SPECT MPI images to measure LV systolic and diastolic dyssynchrony, including phase standard deviation (PSD), phase histogram bandwidth (PBW), and phase entropy (PE). Variables with P < 0.10 in the univariate analysis were included in the multivariate cox analysis.

RESULTS

During the follow-up period (2.9 ± 1.7 years), 18 (34.6%) cardiac deaths were observed. Compared with survivors, patients with cardiac death had lower LVEF (P = 0.011), and more severe LV systolic and diastolic dyssynchrony. The univariate cox regression analysis showed that hypertension, NT-proBNP, LVEF, systolic PSD, systolic PE, and diastolic PBW were statistically significantly associated with cardiac death. The multivariate cox regression analysis showed that systolic PE and diastolic PE were independent predictive factors for cardiac death. Furthermore, the receiver operating characteristic (ROC) analysis, when applied into the combination of systolic PE and diastolic PE for predicting cardiac death, had an area under curve (AUC) of 0.766, a sensitivity of 0.765, and a specificity of 0.722.

CONCLUSIONS

Both the LVSD and LVDD parameters from SPECT MPI have important prognostic values for DCM patients. Both systolic PE and diastolic PE are independent prognostic factors for cardiac death.

Prognostic significance of premature ventricular complex burden on hospitalized patients with heart failure

BACKGROUND

The clinical significance of premature ventricular complexes (PVCs) in heart failure (HF) remains unclear. We aimed to clarify the associations of PVC burden with re-hospitalization and cardiac death in HF patients.

METHODS

We studied 435 HF patients (271 men, mean age 65 years). All patients were hospitalized for worsening HF. After optimal medications, echocardiography, 24 hours Holter monitoring and cardiopulmonary exercise testing were performed before discharge. The clinical characteristics and outcomes of the HF patients were investigated.

RESULTS

During a median follow-up period of 2.3 years, there were 125 (28.7%) cardiac events (re-hospitalization due to worsening HF, fatal arrhythmias, or cardiac death). The patients with cardiac events had higher PVC burden compared to those without (median 0.374%/d [interquartile range 0.013-1.510] vs median 0.026%/d [interquartile range 0.000-0.534], P < .001). We examined cutoff value of PVC burden for predicting cardiac events. Receiver-operating characteristic analysis showed PVC burden (>0.145%/d) to be a predictive factor of cardiac events (area under the curve: 0.64). Kaplan-Meier analysis demonstrated that cardiac events were more frequent in patients with high-PVC burden (>0.145%/d, n = 194) compared to those with low-PVC burden (≤0.145%/d, n = 241). Furthermore, the high-PVC burden patients had left ventricular (LV) and atrial dilatation, reduced LV ejection fraction, and impaired exercise capacity, compared to the low-PVC burden patients. In Cox proportional hazards analysis, high-PVC burden was significantly associated with cardiac events with a hazard ratio of 2.028 (95% confidence interval: 1.418-2.901, P < .001).

CONCLUSION

These results suggest that PVC burden is an important predictor of cardiac events in HF patients.

Electrocardiographic characteristics in patients with heart failure and normal ejection fraction: A systematic review and meta-analysis

BACKGROUND

Little is known about ECG abnormalities in patients with heart failure and normal ejection fraction (HeFNEF) and how they relate to different etiologies or outcomes.

METHODS AND RESULTS

We searched the literature for peer-reviewed studies describing ECG abnormalities in HeFNEF other than heart rhythm alone. Thirty five studies were identified and 32,006 participants. ECG abnormalities reported in patients with HeFNEF include atrial fibrillation (prevalence 12%-46%), long PR interval (11%-20%), left ventricular hypertrophy (LVH, 10%-30%), pathological Q waves (11%-18%), RBBB (6%-16%), LBBB (0%-8%), and long JTc (3%-4%). Atrial fibrillation is more common in patients with HeFNEF compared to those with heart failure and reduced ejection fraction (HeFREF). In contrast, long PR interval, LVH, Q waves, LBBB, and long JTc are more common in patients with HeFREF. A pooled effect estimate analysis showed that QRS duration ≥120 ms, although uncommon (13%-19%), is associated with worse outcomes in patients with HeFNEF.

CONCLUSIONS

There is high variability in the prevalence of ECG abnormalities in patients with HeFNEF. Atrial fibrillation is more common in patients with HeFNEF compared to those with HeFREF. QRS duration ≥120 ms is associated with worse outcomes in patients with HeFNEF. Further studies are needed to address whether ECG abnormalities correlate with different phenotypes in HeFNEF.

Diastolic dyssynchrony and its exercise-induced changes affect exercise capacity in patients with heart failure with reduced ejection fraction

BACKGROUND

Left ventricular diastolic dyssynchrony is common in patients with heart failure with reduced ejection fraction (HFREF). Little is known however, about its pathophysiology and clinical effects. Herein is hypothesized that presence of diastolic dyssynchrony at rest or at exercise may importantly contribute to HF symptoms. The aim was to investigate the influence of diastolic dyssynchrony and its exercise-induced changes on exercise capacity in HFREF patients.

METHODS

Patients with stable, chronic HF, left ventricular ejection fraction < 35%, sinus rhythm and QRS ≥ 120 ms were eligible for the study. Rest and cyclo-ergometer exercise echocardiography were performed. Diastolic dyssynchrony was defined as opposing-wall-diastolic-delay ≥ 55 ms measured in tissue-Doppler imaging. Exercise capacity was assessed by peak oxygen consumption (VO2peak). Association between diastolic dyssynchrony and VO2peak was assessed in univariate regression analysis and further adjusted for possible confounders.

RESULTS

Fourty eight patients were included (aged 63.7 ± 12.2). Twenty-seven (56.25%) had diastolic dyssynchrony at rest and 13 (27%) at exercise. Twenty-two (46%) experienced a change in diastolic dyssynchrony status during exercise. In univariate models diastolic dyssynchrony at rest or at exercise were associated with lower VO2peak (beta coefficient = -3.8, p = 0.004; beta coefficient = -3.6, p = 0.02, respectively). However, the ability to restore diastolic synchronicity during exercise was associated with higher VO2peak (beta coefficient = 3.4, p = 0.04) and remained an important predictor of exercise capacity after adjustment for age and HF etiology.

CONCLUSIONS

The ability to restore diastolic synchronicity at exercise predicts exercise capacity in patients with HFREF.

Cardiac Resynchronization Therapy in Preserved to Mildly Reduced Systolic Function

Cardiac resynchronization therapy has been proven to be clearly beneficial for patients with heart failure, a prolonged QRS duration, and a left ventricular ejection fraction ≤35%. Ejection fraction cutoff, however, is arbitrary and very likely excludes many patients who could benefit from cardiac resynchronization. This article describes the major detrimental effects of left bundle branch block and summarizes the data regarding the potential beneficial effects of cardiac resynchronization in patients with a left ventricular ejection fraction greater than 35%.

New insight into the intraventricular pressure gradient as a sensitive indicator of diastolic cardiac dysfunction in patients with childhood cancer after anthracycline therapy

Cardiac dysfunction due to cardiotoxicity from anthracycline chemotherapy is a leading cause of morbidity and mortality in survivors of childhood cancer. The intraventricular pressure gradient (IVPG) of the left ventricle (LV) is the suction force of blood from the left atrium to the LV apex during early diastole and is a sensitive indicator of diastolic function. We assessed IVPG as a new indicator of the cardiac dysfunction in survivors of childhood cancer after anthracycline therapy. We performed a prospective echocardiographic study on 40 survivors of childhood cancer aged 6-26 years who received anthracycline therapy (group A) and 53 similar-age normal controls (group N). The subjects were divided into the younger groups, N1 and A1 (age < 16 years); older groups, N2 and A2 (age ≥ 16 years). IVPG was calculated using color M-mode Doppler imaging of the mitral inflow using Euler's equation. Total IVPG was divided into the basal and mid-to-apical IVPG to demonstrate more clearly the mechanisms of the LV diastolic suction force. The total anthracycline dose was 16.2-600.0 mg/m² (median 143.5 mg/m²). Total IVPG significantly decreased in group A2 compared with that in group N2 (0.39 ± 0.07 vs. 0.29 ± 0.11 mmHg/cm; p = 0.010). The mid-to-apical IVPG significantly decreased in groups A1 and A2 compared with that in groups N1 and N2, respectively (N1 vs. A1: 0.20 ± 0.05 vs. 0.16 ± 0.05 mmHg/cm, p = 0.036; N2 vs. A2: 0.21 ± 0.06 vs. 0.14 ± 0.06 mmHg/cm, p = 0.001). Basal IVPG, E wave, and E/e' were not significantly different between patients and normal controls. The total and mid-to-apical IVPG, especially mid-to-apical IVPG, could be sensitive new indicators in survivors of childhood cancer after anthracycline therapy.

Changes in mechanical dyssynchrony in severe aortic stenosis patients undergoing transcatheter aortic valve replacement

INTRODUCTION

Aortic stenosis (AS) imposes a significant afterload on the left ventricle, but regional manifestations of the overall load may not be uniform, leading to mechanical dyssynchrony. Accordingly, we evaluated the prevalence of dyssynchrony in patients with severe AS at baseline as well as changes after transfemoral aortic valve replacement (TAVR).

METHODS

This study is a retrospective analysis of 225 patients in sinus rhythm who underwent TAVR for severe AS, in whom inter-ventricular and intra-ventricular dyssynchrony were measured at baseline, discharge, 1 month, and 1 year. Inter-ventricular dyssynchrony was defined as the difference between left and right ventricular pre-ejection intervals; intra-ventricular dyssynchrony was defined as the difference between time to peak systolic velocity of the basal septal and lateral segments. Patients were further stratified into those with QRS <120 ms or >120 ms.

RESULTS

At baseline, a quarter of patients met the criterion for significant inter-ventricular dyssynchrony, and a third had evidence of intra-ventricular dyssynchrony. Both decreased after TAVR although only the intra-ventricular dyssynchrony reached statistical significance. The interplay between QRS duration and changes in inter- and intra-ventricular dyssynchrony are also explored.

CONCLUSIONS

In patients with severe AS, there was evidence of mechanical dyssynchrony that is improved post-TAVR. Whether dyssynchrony is clinically and prognostically significant, and if it represents a potential target for additional therapy remains to be studied.

Electrocardiographic characteristics for predicting idiopathic right ventricular outflow tract premature ventricular complex-induced cardiomyopathy

PURPOSE

In spite of several proposed predictors for premature ventricular complex (PVC)-induced cardiomyopathy (PVC-CMP), the specific ECG features of idiopathic right ventricular outflow tract (RVOT) PVC-CMP remain unknown.

METHODS

A total of 130 patients (49 males, mean age 44 years) with symptomatic and drug-refractory idiopathic RVOT PVCs undergoing radiofrequency catheter ablation (RFCA) were enrolled. The patients were categorized into two groups, including those with and without RVOT PVC-CMP (left ventricular ejection fraction (LVEF) < 50%, n = 25 and LVEF ≥ 50%, n = 105, respectively). The 12-lead PVC morphologies were assessed.

RESULTS

Patients with RVOT PVC-CMP had a lower LVEF (42 ± 5% vs. 60 ± 7%, P < 0.01) and higher PVC burden (24 ± 14% vs. 15 ± 11%, P = 0.02) when compared to patients without RVOT PVC-CMP. The PVC features in those with PVC-CMP displayed a significantly wider QRS duration (143 ± 14 ms vs. 132 ± 17 ms, P < 0.01) and higher peak deflection index (PDI; 0.60 ± 0.07 vs. 0.55 ± 0.08, P < 0.01). A multivariate analysis demonstrated that the QRS duration (odds ratio (OR) 1.130, 95% confidence interval (CI) 1.020-1.253, P = 0.02) and PDI (OR 1.240, 95% CI 1.004-1.532, P = 0.04) were independently associated with RVOT PVC-CMP. Based on the receiver-operating characteristic analysis, a QRS duration > 139 ms and PDI > 0.57 could predict RVOT PVC-CMP (area under the curve (AUC) 0.710 and AUC 0.690, respectively). The elimination and suppression of PVCs by RFCA resulted in the recovery of the LVEF in RVOT PVC-CMP.

CONCLUSIONS

The ECG parameters, including a wider QRS duration and higher PDI, could predict the development of RVOT PVC-CMP, which could be effectively treated by RFCA.

Evaluation of left and right ventricular systolic and diastolic electromechanical synchrony in older people: a population-based observational study

It is unknown whether physiological ageing also goes along with electromechanical asynchrony of contraction. Aim of the study was to evaluate synchrony of contraction in older people with ("non-healthy") or without ("healthy") evidence for structural cardiac disease. In 547 persons (age 76.7+/-5.5 years, 306 male, 241 female) recruited from a population-based cohort of the ActiFE-Ulm study including a random sample of people >/=65 years old living in the region of Ulm, Germany, various PW- and TDI-Doppler based markers for asynchrony were obtained by echocardiography. Within a subgroup of 84 healthy subjects, at most minimal systolic and diastolic asynchrony was found. Concerning systolic asynchrony, similar observations were made within the non-healthy subgroup. However, extent of diastolic left ventricular intraventricular asynchrony and also - by tendency - diastolic interventricular asynchrony was increased in comparison to the healthy subgroup. To conclude, no evidence that physiological ageing might go along with relevant left or right ventricular systolic or diastolic electromechanical asynchrony was found in our study. Furthermore, our population-based data support the results from other clinical studies with rather selected cohorts that structural heart diseases might go along with increased diastolic asynchrony.

Ventricular dyssynchrony in pregnant women: A tissue Doppler study

OBJECTIVE

The aim of the study was to assess the left ventricular (LV) synchronicity in pregnant women and to identify the main determinants of LV dyssynchrony in asymptomatic pregnant women.

METHODS

One hundred sixty-seven pregnant women consecutively and 48 age-matched nonpregnant controls were enrolled. For the assessment of LV systolic dyssynchrony, the standard deviation of the time from QRS onset to peak systolic (Tps-LV- standard deviation [SD]) velocity and the maximal difference of the time from QRS onset to peak systolic velocity (Tps-LV) from 12 segments at the apical views. For the LV diastolic dyssynchrony, the standard deviation of the time from QRS onset to peak diastolic (Tpe-LV-SD) velocity and the maximal difference of the time from QRS onset to peak diastolic velocity (Tpe-LV) were calculated.

RESULTS

Both systolic and diastolic dyssynchrony indexes were significantly higher in pregnant women than in the normal controls (Tps-LV; P<.01, Tps-LV-SD; P<.03, Tpe-LV, P<.05 and Tpe-LV-SD; P<.02). A total of 28 (16.8%) of the pregnant women had a dyssynchrony index above the accepted value for LV dyssynchrony (>34.4 msec). There was a significant correlation between LV dyssynchrony indexes with, multiparty, multifetal pregnancies, systolic blood pressure in pregnant women with LV dyssynchrony. Additionally LV dyssynchrony was significantly associated with elevated E/e" and brain natriuretic peptide (BNP).

CONCLUSIONS

Both systolic synchronicity and diastolic synchronicity were affected in pregnant women compared to nonpregnant women. LV dyssynchrony was significantly correlated with age, multiparity, and BNP level. Early detectable changes in systolic and diastolic synchrony may be present in pregnant women at higher risk of peripartum cardiomyopathy.

Beneficial Effect of Renal Denervation on Ventricular Premature Complex Induced Cardiomyopathy

Background

Frequent ventricular premature complexes (VPCs) can lead to the development of dilated cardiomyopathy and sudden cardiac death. Renal artery sympathetic denervation (RDN) may protect the heart from remodeling. This study aimed to investigate the effect of frequent VPCs on structural and electrical properties and whether RDN can protect the heart from remodeling.

Methods and Results

Eighteen rabbits were randomized to control (n=6), VPC (n=6), and VPC‐RDN (n=6) groups. Surgical and chemical RDNs were approached through bilateral retroperitoneal flank incisions in the VPC‐RDN group. Pacemakers were implanted to the left ventricular apex to produce 50% VPC burden for 5 weeks in the VPC and VPC‐RDN groups. In addition, ventricular myocardium was harvested for western blot and trichrome stain. Echocardiographic results showed left ventricular enlargement after 5‐week pacing in the VPC group, but not in the VPC‐RDN group, when compared to baseline. In biventricles, ion channel protein expressions of Nav1.5, Cav1.2, Kir2.1, and SERCA2 were similar among 3 groups. However, the degree of biventricular fibrosis was extensive in the VPC group, compared to the control and VPC‐RDN groups. Importantly, ventricular fibrillation inducibility was higher in the VPC group (41%) when comparing to the control (13%; P<0.05) and VPC‐RDN groups (13%; P<0.05), respectively.

Conclusions

Frequent VPCs are associated with the development of cardiac structural remodeling and high ventricular fibrillation inducibility. RDN prevents cardiac remodeling and the occurrence of ventricular arrhythmia through antifibrosis.

Real-time three-dimensional left ventricular contraction in patients with diastolic dysfunction

PURPOSE

Systolic alterations in left ventricular (LV) myocardial function have been reported previously in patients with diastolic dysfunction (DD). Recent advances in real-time three-dimensional echocardiography (3DE) enable the measurement of a set of parameters previously difficult to obtain with standard two-dimensional echocardiography (2DE). The aim of this study was to evaluate global 3DE LV contraction in patients with and without DD who had normal ejection fraction (EF).

METHODS

Sixty-five patients (average age 56 ± 6 years; 31 females and 34 males) with normal EF (>50 %) referred to echocardiographic examination for the evaluation of DD were included. In addition to measuring conventional echocardiographic parameters, they were also evaluated with 3DE. End diastolic volume, end systolic volume, EF, corrected standard deviation (SD) of time to minimal systolic volume for 16 segments its dispersion, average excursion of the segments and the SD of segmental motion (excursion-SD) were recorded.

RESULTS

When we tested the differences among three groups of diastolic function (normal, Grade 1, and Grade 2), the results showed that coronary artery disease, left atrial volume, septum, posterior wall, E, A, E/A, deceleration time, E' septum, E' lateral, and excursion-SD were significantly different. An ordered logistic regression analysis revealed that excursion-SD (p < 0.001) and septum (p < 0.001) measurements were statistically significant for predicting DD grade.

CONCLUSION

In our patient population, a decline in excursion-SD values was observed with increasing DD grade. In other words, the amount of segmental difference in terms of excursion was reduced.

QRS Duration Is a Predictor of Adverse Outcomes in Heart Failure With Preserved Ejection Fraction

OBJECTIVES

This study examined the relationship between baseline QRS duration and clinical outcomes in subjects enrolled in the TOPCAT (Treatment of Preserved Cardiac Function Heart Failure With an Aldosterone Antagonist) trial.

BACKGROUND

Heart failure with preserved ejection fraction (HFPEF) is a heterogeneous clinical syndrome. Whether QRS duration identifies HFPEF subjects at an increased risk of adverse outcomes has not been well studied.

METHODS

QRS duration was analyzed as a dichotomous variable (≥120 ms or <120 ms) and as a continuous variable to determine its relation to the primary outcome (composite of cardiovascular death, aborted cardiac arrest, or HF hospitalization [HFH]) and to each component of the primary outcome. Multivariate analyses were conducted in the entire study cohort as well as in separate analyses for subjects enrolled only from North and South America, or from Russia and Georgia.

RESULTS

The QRS duration of ≥120 ms was independently associated with an increased risk of the primary outcome (p = 0.009) and HFH (p = 0.003) in the entire study cohort and in the subset enrolled in the Americas. There was a linear relation of QRS duration with risk of the primary outcome and HFH. No interaction was observed between treatment with spironolactone and QRS duration. The risk of adverse outcomes was increased independently of the type of conduction abnormality underlying prolonged QRS duration.

CONCLUSIONS

This post hoc analysis demonstrated that prolonged QRS duration identifies HFPEF subjects at a higher risk of adverse clinical outcomes and that spironolactone had a similar effect on outcomes independent of QRS duration. (Aldosterone Antagonist Therapy for Adults With Heart Failure and Preserved Systolic Function [TOPCAT]; NCT00094302).

The association among MDCT-derived three-dimensional visceral adiposities on cardiac diastology and dyssynchrony in asymptomatic population

Background

Visceral adipose tissue, a biologically active fat depot, has been proposed as a reliable marker for visceral adiposity and metabolic abnormalities. Effects of such adiposity on LV diastolic function and dyssynchrony remained largely unknown.

Methods

We assessed pericardial fat (PCF) and thoracic peri-aortic fat (TPAF) by three-dimensional (3D) volume-vender multi-detector computed tomography (MDCT) (Aquarius 3D Workstation, TeraRecon, San Mateo, CA, USA). Echo-derived diastolic parameters and tissue Doppler imaging (TDI) defined mitral annular systolic (S’), early diastolic (E’) velocities as well as LV filling (E/E’) were all obtained. Intra-ventricular systolic (Sys-D) and diastolic (Dias-D) dyssynchrony were assessed by TDI method.

Results

A total of 318 asymptomatic subjects (mean age: 53.5 years, 36.8 % female) were eligible in this study. Greater PCF and TPAF were both associated with unfavorable diastolic indices and higher diastolic dyssynchrony (all p < 0.05). These associations remained relatively unchanged in multi-variate models. PCF and TPAF set at 81.68 & 8.11 ml yielded the largest sensitivity and specificity (78.6 and 60 % for PCF, 75 and 66.6 % for TPAF, respectively) in predicting abnormally high LV diastolic dyssynchrony, which was defined as Dias-D≧55 ms.

Conclusion

Increasing visceral adiposity may be associated with adverse effects on myocardium, primarily featured by worse diastolic function and greater degree of dyssynchrony.

Electronic supplementary material

The online version of this article (doi:10.1186/s12872-015-0136-8) contains supplementary material, which is available to authorized users.

Heterogeneous responses of systolic and diastolic left ventricular function to exercise in patients with heart failure and preserved ejection fraction

Aims

This study aimed to evaluate ventricular diastolic properties using three‐dimensional echocardiography and tissue Doppler imaging at rest and during exercise in heart failure with preserved ejection fraction (HFpEF) patients with borderline evidence of diastolic dysfunction at rest.

Methods and results

Results obtained from 52 HFpEF patients (left ventricular ejection fraction ≥ 50%) identified on the basis of heart failure symptoms and E/E′ values between 8 and 15 were compared with those obtained in 26 control patients with no evidence of cardiovascular disease. Mitral flow patterns, tissue Doppler imaging, and volume analysis obtained by three‐dimensional echocardiography were performed at rest and during bicycle exercise. Diastolic compliance was indexed by the E/E′ ratio and left ventricular end‐diastolic volume [(E/E′)/EDV]. There were no significant differences in end‐diastolic volume (EDV), stroke volume (SV), or ejection fraction at rest between groups. In 27 of the 52 patients, E/E′ increased during exercise (11.2 ± 3.7 to 16.8 ± 10.5), driven by a failure to augment early diastole (E′). This correlated with a fall in SV and was associated with an increase in the diastolic index (E/E′)/EDV as a measure for LV stiffness (0.122 ± 0.038 to 0.217 ± 0.14/mL), indicating that impaired diastolic reserve (designated PEF‐I_DR) contributed to exercise intolerance. Of the 52 patients, 25 showed no changes in E/E′ during exercise associated with a significant rise in SV and cardiac output, still inappropriate compared with controls. Despite disturbed early diastole (E′), a blunted increase in estimated systolic LV elastance indicated that impaired systolic reserve and chronotropic incompetence rather than primarily diastolic disturbances contributed to exercise intolerance in this group (designated PEF).

Conclusion

Three‐dimensional stress echocardiography may allow non‐invasive analysis of changes in cardiac output that can differentiate HFpEF patients with an inappropriate increase or a fall in SV during exercise. Impaired systolic or diastolic reserve can contribute to these haemodynamic abnormalities, which may arise from different underlying pathophysiologic mechanisms.

Prognostic significance of persistent restrictive filling pattern after cardiac resynchronization therapy

BACKGROUND

Cardiac resynchronization therapy (CRT) may improve left ventricular (LV) diastolic dysfunction as well as systolic dysfunction. Diastolic dysfunction is a key for prognosis in patients with heart failure; therefore, we aimed to clarify the impact of CRT on diastolic function and prognosis.

METHODS

In 67 patients who underwent CRT, LV diastolic function was assessed by pulsed Doppler transmitral flow pattern at baseline and 1 week after CRT, and classified into restrictive filling pattern (RFP) and non-RFP groups. Volume responders were defined by reduction of LV end-systolic volume >15% at 6 months after CRT. The clinical endpoint comprised death from any cause or unplanned hospitalization for a major cardiovascular event (MACE).

RESULTS

During the follow-up period (479 ± 252 days), 26 patients (38.8%) had reached the endpoint of MACE. In Cox proportional hazard analyses, RFP at 1 week after CRT was associated with the endpoints independently of age and New York Heart Association (NYHA) class IV at baseline. Thirty (44.8%) patients were identified as volume responders, who had better prognosis than non-responders. Patients were classified into 4 groups based on their filling pattern at 1 week after CRT and volume responses. The worst prognosis was observed in the RFP and non-responder group, and the best was observed in the non-RFP and responder group. For the remaining 2 groups with intermediate prognosis, the RFP and responder group showed poorer prognosis compared to the non-RFP and non-responder group.

CONCLUSIONS

Persistent RFP after CRT may be a strong prognostic predictor, which should be treated with more intensive therapy to improve the prognosis of patients following CRT.

Relationship between epicardial fat tissue and left ventricular synchronicity: An observational study

Objective:

Left ventricular (LV) systolic synchrony is defined as simultaneous activation of corresponding cardiac segments. Impaired synchrony has some adverse cardiovascular effects, such as LV dysfunction and impaired prognosis. Epicardial fat tissue (EFT) is visceral fat around the heart. Increased EFT thickness is associated with some disorders, such as LV dysfunction and hypertrophy, which play a role in the impairment of LV synchrony. However, the relationship between EFT and LV systolic synchrony has never been assessed. Thus, we aimed to evaluate the possible relationship between EFT and LV synchrony in this study.

Methods:

The study population consisted of 55 consecutive patients (mean age 46.4±13.4 years, 32 female) without bundle branch block (BBB). EFT and LV systolic synchrony were evaluated by transthoracic echocardiography using 2D and tissue Doppler imaging. Maximal difference (Ts-6) and standard deviation (Ts-SD-6) of time to peak systolic (Ts) myocardial tissue velocity obtained from 6 LV basal segments were used to assess LV synchrony. Multiple regression analysis was used to detect the independently related factors to LV synchrony.

Results:

The mean values of EFT thickness, Ts-6, and Ts-SD-6 were found to be 2.7±1.6 mm (ranging from 1-7 mm), 20.1±14.2 msec, and 7.7±5.6, respectively. EFT thickness also was independently associated with Ts-6 (β =0.332, p=0.01) and Ts-SD-6 (β =0.286, p=0.04).

Conclusion:

EFT thickness is associated with LV systolic synchrony in patients without BBB.

Acute Effects of Biventricular Pacing in Heart Failure Patients with a Normal Ejection Fraction and Mechanical Dyssynchrony

Objectives: We tested the acute effects of resynchronization in heart failure patients with a normal (>50%) left ventricular (LV) ejection fraction (HFNEF) and mechanical dyssynchrony. Methods: Twenty-four HFNEF patients (72 ± 6 years, 5 male) with mechanical dyssynchrony (standard deviation of electromechanical time delay among 12 LV segments >35 ms) were studied with temporary pacing catheters in the right atrium, LV, and right ventricle (RV), and high-fidelity catheters for pressure recording. Using selected atrioventricular (AV) intervals of 60, 90, 120, 150, and 180 ms to optimize transmitral flow during simultaneous biventricular pacing, the RV-LV (VV) interval was then evaluated at RV30, RV15, 0, LV15, LV30, and LV45 (RV or LV indicates which ventricle was paced first, the number indicates by how many ms). Results: During simultaneous pacing, longer AV intervals were associated with improved LV pressure-derivative minimums and increased aortic pressures (p < 0.05 vs. normal sinus rhythm). In the VV interval from RV30 to LV45, there was a graded increase in the aortic velocity time integral and a decrease in dyssynchrony during simultaneous or LV-first pacing (p < 0.05 vs. normal sinus rhythm). Conclusions: For HFNEF patients with mechanical dyssynchrony, acute simultaneous biventricular or LV-first pacing with longer AV intervals reduced mechanical dyssynchrony and improved diastolic and systolic hemodynamics.

Early diastolic dyssynchrony in relation to left ventricular remodeling and function in hypertension

BACKGROUND

Cardiac synchronization is important in maintaining myocardial performance, but the mechanism of diastolic dyssynchrony leading to failing myocardium is unclear. We aim to study the relation of left ventricular (LV) diastolic dyssynchrony with diastolic dysfunction in patients with hypertension.

METHODS

Two-D, three-D and Doppler echocardiography were performed using the GE Vivid E9 system on 230 subjects. Among them, 154 patients with hypertension were divided into group 1 (86 patients with mild to moderate hypertension, BP 152 ± 8/91 ± 11 mm Hg) and group 2 (68 patients with severe hypertension, BP 188 ± 12/105 ± 24 mm Hg), age 76, gender matched normotensive subjects (119 ± 6/76 ± 9 mm Hg) as control. The routine 2D and Doppler parameters were measured and LV systolic and diastolic dyssynchrony indices were determined as the standard deviation of the time interval from the peak R of the QRS complex to peak myocardial systolic strain rate (Ts-SD), and to early diastolic strain rate (Te-SD) of 12 LV segments.

RESULTS

LV relative wall thickness, mass index, and Te-SD were significantly higher in patients with hypertension than in control group (p<0.0001), but Ts-SD showed no significant differences. Te-SD and diastolic dysfunction worsened progressively with increasing severity of hypertension (p<0.05). Te-SD was significantly and independently associated with parameters of LV remodeling and diastolic function.

CONCLUSION

Our study demonstrated that LV diastolic dyssynchrony was associated with LV remodeling, which seems to contribute to diastolic dysfunction in hypertension. This diastolic dyssynchrony index derived from speckle tracking echocardiography can be used as a marker for studying the LV function and effects of therapy in hypertensive heart disease.

Is mechanical dyssynchrony a therapeutic target in heart failure with preserved ejection fraction?

BACKGROUND

Previous studies have found a high frequency of mechanical dyssynchrony in patients with heart failure (HF) with preserved ejection fraction (HFpEF), hence suggesting that cardiac resynchronization therapy (CRT) may be considered in HFpEF. The present study was designed to compare the amount of mechanical dyssynchrony between HFpEF patients and (1) HF with reduced EF (HFrEF) patients with an indication for CRT (HFrEF-CRT(+)) group, (2) HFrEF patients with QRS duration < 120 ms (HFrEF-QRS < 120 ms) group, and (3) hypertensive controls (HTN).

METHODS

Electrical (ECG) and mechanical dyssynchrony (atrio-ventricular dyssynchrony, interventricular dyssynchrony, intraventricular dyssynchrony) were assessed using conventional, tissue Doppler, and Speckle Tracking strain echocardiography in 40 HFpEF patients, 40 age- and sex-matched HTN controls, 40 HFrEF-QRS < 120 ms patients, and 40 HFrEF-CRT(+) patients.

RESULTS

The frequency of left bundle branch block was low in HFpEF patients (5%) and similar to HTN controls (5%, P = 0.85). Indices of dyssynchrony were similar between HFpEF and HTN patients or HFrEF-QRS < 120 ms patients. In contrast, most indices of dyssynchrony differed between HFpEF and HFrEF-CRT(+) patients. The principal components analysis on the entire cohort of 160 patients yielded 2 homogeneous groups of patients in terms of dyssynchrony, the first comprising HFrEF-CRT(+) patients and the second comprising HTN, HFrEF-QRS < 120 ms and HFpEF patients.

CONCLUSIONS

Mechanical dyssynchrony in HFpEF does not differ from that of patients with HTN or patients with HFrEF and a narrow QRS. This data raises concerns regarding the role of dyssynchrony in the pathophysiology of HFpEF and thereby the potential usage of CRT in HFpEF.

Ejection fraction in patients with heart failure and preserved ejection fraction is greater than in healthy controls: a meta-analysis

BACKGROUND

Ejection fraction (EF) slightly declines with age in healthy control (HC) subjects. Yet, studies of heart failure with preserved ejection fraction (HFPEF) often report EF values which are surprisingly greater than those reported for HC of the same age. The goals of this study were to: (1) compare the EF, at rest, in subjects with HFPEF versus HC, and (2) compare how EF varies with age in HFPEF and HC.

METHODS

A systematic review and meta-analysis of the literature was performed. Studies were identified in the PUBMED and EMBASE databases until August 2013. A study reporting EF at rest in HFPEF and HC was included regardless of the aim of the primary study. In most of the primary studies (25 of 28 studies, 89%) EF was not a primary endpoint. A summary measure was the standardized mean difference (SMD) of the EF in HFPEF vs.

HC RESULTS

Twenty eight studies (1529 HFPEF and 1068 HC subjects) were included. SMD was 0.71 (95% CI: 0.31, 1.12, P<0.001) demonstrating a greater EF in HFPEF. Effect size of HFPEF on EF was moderate. A meta-regression showed a statistically non-significant trend of increased SMD with older age.

CONCLUSIONS

This analysis showed that EF in HFPEF is on average "greater-than-normal". This phenomenon may be related to an underlying adaptive mechanism occurring in HFPEF. Further research is needed.

New strategies for heart failure with preserved ejection fraction: the importance of targeted therapies for heart failure phenotypes

The management of heart failure with reduced ejection fraction (HF-REF) has improved significantly over the last two decades. In contrast, little or no progress has been made in identifying evidence-based, effective treatments for heart failure with preserved ejection fraction (HF-PEF). Despite the high prevalence, mortality, and cost of HF-PEF, large phase III international clinical trials investigating interventions to improve outcomes in HF-PEF have yielded disappointing results. Therefore, treatment of HF-PEF remains largely empiric, and almost no acknowledged standards exist. There is no single explanation for the negative results of past HF-PEF trials. Potential contributors include an incomplete understanding of HF-PEF pathophysiology, the heterogeneity of the patient population, inadequate diagnostic criteria, recruitment of patients without true heart failure or at early stages of the syndrome, poor matching of therapeutic mechanisms and primary pathophysiological processes, suboptimal study designs, or inadequate statistical power. Many novel agents are in various stages of research and development for potential use in patients with HF-PEF. To maximize the likelihood of identifying effective therapeutics for HF-PEF, lessons learned from the past decade of research should be applied to the design, conduct, and interpretation of future trials. This paper represents a synthesis of a workshop held in Bergamo, Italy, and it examines new and emerging therapies in the context of specific, targeted HF-PEF phenotypes where positive clinical benefit may be detected in clinical trials. Specific considerations related to patient and endpoint selection for future clinical trials design are also discussed.

Assessment of left ventricular dyssynchrony in patients with psoriasis

BACKGROUND

Psoriasis is an inflammatory disorder, which has been reported to be associated with cardiovascular (CV) risks. Although increased CV risks in psoriasis are well established, there are no data about changes of contraction synchrony in psoriasis. Therefore, we aimed to study the left ventricular (LV) contraction synchrony in patients with psoriasis with narrow QRS and normal ejection fraction.

METHODS

Fifty patients with psoriasis and 50 age- and sex-matched control subjects were included in the study. LV dyssynchrony was investigated by color-coded tissue Doppler imaging.

RESULTS

In the psoriasis group, the mean high-sensitive C-reactive protein values were significantly higher compared with the controls. Peak A velocity, deceleration time, isovolumetric relaxation time, and E/E' values were higher in the psoriasis group; however, E/A ratio and average Em were higher in the control group. LV systolic dyssynchrony parameters [including standard deviation of Ts of the 12 LV segments (Ts-SD-12), maximal difference in Ts between any two of the 12 LV segments, standard deviation of Ts of the six basal LV segments, and maximal difference in Ts between any two of the six basal LV segments] were found to be higher in the psoriasis group. The patients with ventricular dyssynchrony (a Ts-SD-12 >34.4 ms) were higher in the psoriasis group than the control group (34% vs. 6%, P < 0.01).

CONCLUSION

In patients with psoriasis with normal ejection fractions and narrow QRS, LV systolic dyssynchrony is an early manifestation of heart involvement and may coexist with diastolic dysfunction.

Correlation between systolic deformation and dyssynchrony indices and the grade of left ventricular hypertrophy in hypertensive patients with a preserved systolic ejection fraction undergoing coronary angiography, based on tissue Doppler imaging

OBJECTIVES

The purpose of this study was to investigate whether systolic mechanical dyssynchrony occurs in hypertensive patients with a normal coronary artery and a normal ejection fraction and its relationship with different degrees of left ventricular (LV) hypertrophy.

METHODS

A total of 125 angiographically normal coronary patients (42.4% male; mean age ± SD, 57.16 ± 8.26 years) with an ejection fraction greater than 50% were included, of which 84 were hypertensive and 41 normotensive. The hypertensive patients were categorized into 3 groups: no, mild, and moderate LV hypertrophy. Tissue Doppler and deformation imaging parameters were measured in the 6 LV basal segments at peak systole.

RESULTS

The frequency of dyssynchrony was 40.5% in the hypertensive patients compared to 19.5% in the control patients (P = .020). Among the hypertensive patients, LV dyssynchrony was found in 5 patients (20%) with no hypertrophy, 20 (42.6%) with mild hypertrophy, and 9 (75%) with moderate hypertrophy. There was a moderate correlation between the grade of hypertrophy and septal-lateral wall delay (r = 0.497), 6-basal segment delay (r = 0.454), overall strain (r = 0.453), overall peak systolic velocity (r = -0.430), and standard deviation of the time to peak systolic velocity in the basal segments (r = 0.429). After adjustment for the LV end-systolic diameter and body surface area, overall strain was the best correlate of the hypertrophy grade (odds ratio, 7.043; 95% confidence interval, 1.839-26.980; P = .0044).

CONCLUSIONS

Among tissue Doppler and deformation indices, overall peak systolic strain was the strongest correlate of the LV hypertrophy grade. Therefore, in hypertensive patients with normal cardiac systolic function, a reduction in overall strain in the 6 basal LV segments may be a good indicator of progression of the LV hypertrophy grade and systolic dysfunction.

Catheterization diastolic pressures correlate with diastolic dyssynchrony in patients with single right ventricles

INTRODUCTION

Diastolic dyssynchrony has correlated with pulmonary capillary wedge pressures in patients with normal cardiac anatomy. No data exist in single right ventricle (sRV) patients. Goal of this study was to determine if diastolic dyssynchrony in sRV patients correlates with ventricular end-diastolic pressures (VEDP).

METHODS

Tissue Doppler imaging (TDI) and strain rate (SR) analysis of sRV patients undergoing catheterization were performed. Time interval from onset of QRS to peak TDI e'-wave was obtained. Differences in intervals were calculated: QRS (RV) - QRS (IVS) and QRS (RV) - QRS (LV). Time interval from onset of QRS to peak strain rate early diastolic wave (SRe) was obtained for the 6 segment model sRV. Standard deviation of the 6 SRe time intervals was calculated. Correlation of VEDP with timing intervals was analyzed.

RESULTS

Forty sRV patients were evaluated. Age was 2.8 ± 3.5 years. Catheterization VEDP of the sRV was 9.3 ± 3.9 mmHg (median 8 mmHg range 4-24 mmHg). QRS (RV) - QRS (IVS) was 22.3 ± 18.1 msec and QRS (RV) - QRS (LV) was 23.7 ± 19.0 msec. SRe standard deviation of the sRV was 61.6 ± 23.9 msec. There was no significant correlation with VEDP and QRS (RV) - QRS (IVS) (r = 0.1, P = NS) or with QRS (RV) - QRS (LV) (r = 0.2, P = NS). There was a significant correlation of VEDP with the SRe standard deviation value (r = 0.4, P < 0.05).

CONCLUSION

Diastolic dyssynchrony correlated with VEDP in patients with sRV physiology. Future studies are needed to determine the significance of these findings.