Evaluation of diastolic filling of left ventricle in health and disease: Doppler echocardiography is the clinician's Rosetta Stone

Vascular and Microvascular Endothelial Function in Heart Failure With Preserved Ejection Fraction

BACKGROUND

Assessment of vascular endothelial function lacks consistency, and microvascular endothelial function has been only partly assessed in heart failure with preserved ejection fraction (HFpEF).

METHODS

The study population consisted of 90 patients: 45 had well documented HFpEF, and 45 had hypertension and no history or evidence of heart failure. Patients with hypertension but no heart failure were matched with HFpEF patients for age, sex, and diabetes. They served as control subjects. All patients underwent 2-dimensional Doppler echocardiography and vascular function measurements, including assessment of arterial wave reflections and arterial stiffness, brachial artery flow-mediated dilation (FMD), and forearm cutaneous blood flow with the use of a laser Doppler flow probe at rest and after release of arterial occlusion for 5 minutes.

RESULTS

Brachial artery FMD was lower in HFpEF than in control subjects (median (IQR) 3.6 (0.4-7.4) vs. 7.2 (3.2-17.2)%, P = .001). Forearm cutaneous blood flow at rest was similar in HFpEF and control subjects (P = .68). After release of arterial occlusion, forearm cutaneous peak blood flow was lower in HFpEF than in control subjects (P = .03). Estimated aortic systolic and mean blood pressures were similar in HFpEF and control subjects, whereas pulse pressure and pressure augmentation were greater in HFPEF than in control subjects (both P < .05).

CONCLUSION

Compared with hypertensive control subjects, patients with HFpEF had a depressed endothelial function in the forearm vasculature and microvasculature.

The Diagnostic Value of Pulsed Wave Tissue Doppler Imaging in Asymptomatic Beta- Thalassemia Major Children and Young Adults; Relation to Chemical Biomarkers of Left Ventricular Function and Iron Overload

BACKGROUND

Cardiac iron toxicity is the leading cause of death among β-halassaemia major (TM) patients. Once heart failure becomes overt, it is difficult to reverse.

OBJECTIVES

To investigate non-overt cardiac dysfunctions in TM patients using pulsed wave Tissue Doppler Imaging (TD I) and its relation to iron overload and brain natriuretic peptide (BNP).

METHODS

Thorough clinical, conventional echo and pulsed wave TDI parameters were compared between asymptomatic 25 β-TM patients and 20 age and gender matched individuals. Serum ferritin and plasma BNP levels were assayed by ELISA.

RESULTS

TM patients had significant higher mitral inflow early diastolic (E) wave and non significant other conventional echo parameters. In the patient group, pulsed wave TDI revealed systolic dysfunctions, in the form of significant higher isovolumetric contraction time (ICT), and lower ejection time (E T), with diastolic dysfunction in the form of higher isovolumetric relaxation time (IRT), and lower mitral annulus early diastolic velocity E' (12.07 ±2.06 vs 15.04±2.65, P= 0.003) compared to the controls. Plasma BNP was higher in patients compared to the controls. Plasma BNP and serum ferritin had a significant correlation with each other and with pulsed wave conventional and TDI indices of systolic and diastolic functions. Patients with E/E' ≥ 8 had significant higher serum ferritin and plasma BNP levels compared to those with ratio < 8 without a difference in Hb levels.

CONCLUSION

Pulsed wave TDI is an important diagnostic tool for latent cardiac dysfunction in iron-loaded TM patients and is related to iron overload and BNP.

The Utility of 3D Left Atrial Volume and Mitral Flow Velocities as Guides for Acute Volume Resuscitation

Left ventricular end-diastolic pressure (LVEDP) is the foundation of cardiac function assessment. Because of difficulties and risks associated with its direct measurement, correlates of LVEDP derived by pulmonary artery (PA) catheterization or transesophageal echocardiography (TEE) are commonly adopted. TEE has the advantage of being less invasive; however TEE-based estimation of LVEDP using correlates such as left ventricular end-diastolic volume (LVEDV) has technical difficulties that limit its clinical usefulness. Using intraoperative acute normovolemic hemodilution (ANH) as a controlled hemorrhagic model, we examined various mitral flow parameters and three-dimensional reconstructions of left atrial volume as surrogates of LVEDP. Our results demonstrate that peak E wave velocity and left atrial end-diastolic volume (LAEDV) correlated with known changes in intravascular volume associated with ANH. Although left atrial volumetric analysis was done offline in our study, recent advances in echocardiographic software may allow for continuous display and real-time calculation of LAEDV. Along with the ease and reproducibility of acquiring Doppler images of flow across the mitral valve, these two correlates of LVEDP may justify a more widespread use of TEE to optimize intraoperative fluid management. The clinical applicability of peak E wave velocity and LAEDV still needs to be validated during uncontrolled resuscitation.

Tissue Doppler and strain imaging of left ventricle in Beagle dogs with iatrogenic hypercortisolism

Changes in radial and longitudinal left ventricular (LV) function were investigated in beagles with iatrogenic hypercortisolism. A total of 11 normal dogs were used, and 2 mg/kg prednisone was administered per oral q12 h for 28 days to 7 out of 11 dogs to induce iatrogenic hypercortisolism. Body weight, blood pressure, conventional echocardiography and tissue Doppler imaging (TDI) of normal and iatrogenic hypercortisolism groups were conducted. The myocardial wall velocity of the LV was measured using color TDI and myocardial deformation was determined by the strain and strain rate. Conventional echocardiography revealed that the diastolic LV free wall and interventricular septum in the hypercortisolism group were thickened relative to those in the normal group. The peak early diastolic myocardial velocity and early to late diastolic myocardial velocity ratio of TDI in the hypercortisolism group were significantly lower than those in the normal group. The strain values in the hypercortisolism group were significantly lower than those in the normal group, particularly for longitudinal wall motion. The lower values of myocardium from TDI and strain imaging could be used to investigate subclinical LV systolic and diastolic dysfunction in dogs with the iatrogenic hypercortisolism.

Diastolic Dysfunction Occurs Early in HER2-Positive Breast Cancer Patients Treated Concurrently With Radiation Therapy and Trastuzumab

BACKGROUND

Left ventricular ejection fraction (LVEF) is used routinely to monitor cardiac dysfunction associated with breast cancer treatment. In this study the prevalence of early left ventricular diastolic dysfunction (LVDD) and its relationship to the dose-volume of the heart irradiated were evaluated in HER2-positive breast cancer patients undergoing concurrent trastuzumab and adjuvant radiotherapy (RT).

MATERIALS AND METHODS

Data from 40 breast cancer patients treated with concurrent trastuzumab and left-sided adjuvant RT between September 2011 and October 2012 were collected prospectively. For comparison, 32 patients treated with concurrent trastuzumab and right-sided adjuvant RT and 71 patients treated with left-sided RT alone were collected retrospectively. Echocardiography was obtained before RT, immediately following RT, and 3 and 6 months after RT. Doses to the heart and left ventricle (LV) were quantified.

RESULTS

Prior to RT with concurrent trastuzumab, 11 of 29 (left) and 8 of 25 (right) patients with normal baseline left ventricular diastolic function (LVDF) developed LVDD. In patients receiving left-sided RT alone, 12 of 61 patients with normal baseline LVDF developed LVDD. Dmean, D15-D40, D60-D70, and V3-V10 of the LV were significantly higher in patients who developed LVDD after concurrent trastuzumab and left-sided RT. In contrast, only two patients developed grade 1 LVEF decrease after both concurrent treatment and left-sided RT alone.

CONCLUSION

Changes in LVDF compared with LVEF are more sensitive for early detection of cardiotoxicity. The dose-volume of the heart contributes significantly to the risk of LVDD in patients with left-sided breast cancer treated concurrently with trastuzumab.

IMPLICATIONS FOR PRACTICE

Abnormalities in diastolic function are more sensitive than changes in the left ventricular ejection fraction for detecting acute cardiotoxicity and are related to the dose-volume of the heart irradiated in patients with left-sided breast cancer receiving radiotherapy concurrently with trastuzumab. This result highlights the importance of decreasing the dose-volume of heart irradiated as a protective strategy in the treatment setting of concurrent trastuzumab and radiotherapy. Diastolic dysfunction may serve as a more sensitive tool for the early detection of cardiac damage and should be incorporated as a routine parameter in the functional monitoring of cardiotoxicity.

Clinical phenotype and outcome of hypertrophic cardiomyopathy associated with thin-filament gene mutations

Background

Mild hypertrophy but increased arrhythmic risk characterizes the stereotypic phenotype proposed for hypertrophic cardiomyopathy (HCM) caused by thin-filament mutations. However, whether such clinical profile is different from more prevalent thick-filament–associated disease is unresolved.

Objectives

This study aimed to assess clinical features and outcomes in a large cohort of patients with HCM associated with thin-filament mutations compared with thick-filament HCM.

Methods

Adult HCM patients (age >18 years), 80 with thin-filament and 150 with thick-filament mutations, were followed for an average of 4.5 years.

Results

Compared with thick-filament HCM, patients with thin-filament mutations showed: 1) milder and atypically distributed left ventricular (LV) hypertrophy (maximal wall thickness 18 ± 5 mm vs. 24 ± 6 mm; p < 0.001) and less prevalent outflow tract obstruction (19% vs. 34%; p = 0.015); 2) higher rate of progression to New York Heart Association functional class III or IV (15% vs. 5%; p = 0.013); 3) higher prevalence of systolic dysfunction or restrictive LV filling at last evaluation (20% vs. 9%; p = 0.038); 4) 2.4-fold increase in prevalence of triphasic LV filling pattern (26% vs. 11%; p = 0.002); and 5) similar rates of malignant ventricular arrhythmias and sudden cardiac death (p = 0.593).

Conclusions

In adult HCM patients, thin-filament mutations are associated with increased likelihood of advanced LV dysfunction and heart failure compared with thick-filament disease, whereas arrhythmic risk in both subsets is comparable. Triphasic LV filling is particularly common in thin-filament HCM, reflecting profound diastolic dysfunction.

Radius of proximal isovelocity surface area in the assessment of rheumatic mitral stenosis: Connecting flow to anatomy and hemodynamics

Background

Echocardiographic assessment of left atrial pressure (LAP) in mitral stenosis (MS) is controversial. We sought to examine the role of the radius of the proximal isovelocity surface area (PISA-r) in the assessment of the hemodynamic status of MS after fixing the aliasing velocity (Val).

Methods and results

We studied 42 candidates of balloon mitral valvuloplasty (BMV), for whom pre-BMV echocardiography was done and LAP invasively measured before dilatation. PISA-r was calculated after fixing aliasing velocity to 33 cm/s. In addition, the ratio IVRT/Te’–E was also measured, where IVRT was isovolumic relaxation time, and Te’–E was the time difference between the onset of mitral flow E-wave and mitral annular early diastolic velocity. IVRT/Te’–E and PISA-r showed a strong correlation with LAP (r = −0.715 and −0.637, all p < 0.001) and with right-sided pressures. In addition, PISA-r correlated with mitral valve area by planimetry method (MVA) and with left ventricular outflow tract stroke volume (r = 0.66 and 0.71, all p < 0.001). Receiver operator characteristic curve (ROC-curve) showed that PISA-r was not inferior to IVRT/Te’–E in differentiating LAP ⩾25 from <25 mmHg.

Conclusion

Provided that Val is set to a constant of 33 cm/s, PISA-r can assess the hemodynamic status of MS, and seems a simple alternative to the tedious IVRT/Te’–E for estimation of LAP.

Left ventricular diastolic function, assessed by echocardiography and tissue Doppler imaging, is a strong predictor of cardiovascular events, superior to global left ventricular longitudinal strain, in patients with type 2 diabetes

AIMS

The aim of the study was to determine whether left ventricular systolic function, in terms of global left ventricular longitudinal strain (GLS), and diastolic function, expressed as the ratio between early diastolic transmitral flow and mitral annular motion velocities (E/e'), can predict cardiovascular events in patients with diabetes mellitus type 2.

METHODS AND RESULTS

We prospectively investigated 406 consecutive patients, aged 55-65 years, with diabetes mellitus, who participated in the CARDIPP study. Echocardiography, pulse pressure (pp), and glycosylated haemoglobin (HbA1c) were analysed. Twelve cases of myocardial infarction and seven cases of stroke were identified during the follow-up period of 67 ± 17 months. Univariate Cox regression analysis showed that E/e' was a strong predictor of cardiovascular events (hazards ratio 1.12; 95% confidence interval 1.06-1.18, P < 0.001). E/e' was prospectively associated with cardiovascular events independent of age, sex, GLS, left ventricular ejection fraction (LVEF), pp, and HbA1c in multivariate analysis. Receiver operating characteristic curves showed that E/e' and HbA1c were the strongest predictors for cardiovascular events, both having an area under the curve (AUC) of 0.71 followed by LVEF with an AUC of 0.65 and GLS of 0.61. In a Kaplan-Meyer analysis, the cumulative probability of an event during the follow-up period was 8.6% for patients with an E/e' ratio >15 compared with 2.6% for patients with E/e' ≤15, P = 0.011.

CONCLUSION

In middle-aged patients with type 2 diabetes, E/e' is a strong predictor of myocardial infarction and stroke, comparable with HbA1c and superior to GLS and LVEF.

Prevalence and prognostic role of right ventricular involvement in stress-induced cardiomyopathy

BACKGROUND

Stress-induced cardiomyopathy (SCM) is a reversible cardiomyopathy observed in patients without significant coronary disease. The aim of this study was to assess the incidence and clinical significance of right ventricular (RV) involvement in SCM.

METHODS AND RESULTS

We retrospectively analyzed echocardiograms from 40 consecutive patients who presented with SCM at Stanford University Medical Center from September 2000 to November 2010. The primary end point was overall mortality. RV involvement was observed in 20 patients (50%; global RV hypokinesia in 15 patients and focal RV apical akinesia in 5 patients). The independent correlates of RV involvement were older age (odds ratio [OR] 1.09, 95% confidence interval [CI] 1.02-1.7two, P = .01) and LVEF (per 10% decrease: OR 3.60, CI 1.77-7.32; P = .02). At a mean follow-up of 44 ± 32 months, 12 patients (30%) died (in-hospital death in 3 patients). At multivariate analysis, the presence of an RV fractional area change <35% emerged as an independent predictor of death (OR 3.6, CI 1.06-12.41; P = .04).

CONCLUSIONS

RV involvement is a common finding in SCM, and may present as either global or focal RV apical involvement. Both older age and lower LVEF are associated with a higher risk of RV involvement, which appears to be a major predictor of death.

Echocardiographic evaluation of diastolic dysfunction in rheumatoid arthritis - a case-control study

OBJECTIVES

To assess left ventricular diastolic dysfunction (LVDD) and its predictors in rheumatoid arthritis (RA).

METHODS

This cross-sectional case-control study assessed 100 RA patients and 100 healthy controls for LVDD by M-mode, two-dimensional, colour Doppler echocardiography.

RESULTS

RA patients had higher prevalence of LVDD than controls (43% vs. 14%; p < 0.001). LVDD had significant association with duration (p = 0.033), severity of disease activity (p < 0.0001), Steinbrocker stage and functional class (p < 0.0001 each) and non-adherence to treatment (p = 0.047). Peak of late diastolic (A) mitral flow velocity and isovolumic relaxation time (IVRT) were higher (p < 0.05 each), whereas left ventricular ejection fraction, peak of early diastolic (E) mitral flow velocity and E/A ratio were lower (p < 0.05 each) in RA patients than in controls. Deceleration time (DT) was not significantly different in the two groups (p = 0.623). E/A ratio had significant correlation with anti-cyclic citrullinated peptide antibody (ACPA) (r = 0.233, p = 0.019) and age (r = 0.203, p = 0.042). IVRT had significant negative correlation with ACPA (r = -0.196, p = 0.044), while DT had significant correlation with Disease Activity Score with 28-joint (DAS28) counts (r = 0.244, p = 0.014). ACPA was an independent predictor of E/A ratio (p = 0.031). DAS28 was the only independent predictor of LVDD (odds ratio [OR] = 6.01; p = 0.007).

CONCLUSIONS

LVDD occurred commonly in RA patients and depended on severity of disease activity.

Two-slope ascending arm of the early trans-mitral flow velocity Doppler wave in patients with heart failure and preserved ejection fraction

Trans-mitral flow velocity (TMFV) examination is a standard echocardiographic measure for assessing diastolic function of the heart. Typically, the Doppler signal representing the early rapid filling phase of the left ventricle (LV), termed: E wave, is triangular. The ascending arm of the E wave (EWAA) represents blood accelerating into the LV from the left atrium (LA), whereas the descending arm reflects blood decelerating as the LV fills and resists further filling. The slope of EWAA is linear, starting at TMFV of zero cm/s (prior to mitral valve opening) and building to peak E wave value. The physical meaning of a single slope is that blood acceleration is constant with time. Little data exist regarding the significance of the shape of EWAA. It is hypothesized that in heart failure with preserved ejection fraction (HFPEF) the EWAA displays 2 slopes. A first steeper slope followed by a second less steep slope reaching peak E wave. The different slopes represent a change in the composition of driving forces propelling blood from LA to LV. It is hypothesized that the first steeper slope of EWAA represents a set of driving force including a force termed: diastolic suction, whereas in the second slope diastolic suction has already dissipated. This 2-slope phenomenon is not expected in healthy subjects because the assumed underlying mechanism is not operative.

A finite strain nonlinear human mitral valve model with fluid-structure interaction

A computational human mitral valve (MV) model under physiological pressure loading is developed using a hybrid finite element immersed boundary method, which incorporates experimentally-based constitutive laws in a three-dimensional fluid-structure interaction framework. A transversely isotropic material constitutive model is used to characterize the mechanical behaviour of the MV tissue based on recent mechanical tests of healthy human mitral leaflets. Our results show good agreement, in terms of the flow rate and the closing and opening configurations, with measurements from in vivo magnetic resonance images. The stresses in the anterior leaflet are found to be higher than those in the posterior leaflet and are concentrated around the annulus trigons and the belly of the leaflet. The results also show that the chordae play an important role in providing a secondary orifice for the flow when the valve opens. Although there are some discrepancies to be overcome in future work, our simulations show that the developed computational model is promising in mimicking the in vivo MV dynamics and providing important information that are not obtainable by in vivo measurements.

Echocardiographic estimation of left ventricular filling pressures in patients with mitral valve stenosis

Background

Estimation of left ventricular end-diastolic pressure (LVEDP) among patients with mitral valve disease may help to explain their symptoms. However, conventional Doppler measurements have limitations in predicting LVEDP in this group of patients. The aim of this study was to construct a Doppler-derived LVEDP prediction model based on the combined analysis of transmitral and pulmonary venous flow velocity curves.

Methods

Thirty-three patients with moderate to severe mitral stenosis (MS) who had indications for left heart catheterisation enrolled. Two-dimensional, M-mode, colour Doppler and tissue Doppler imaging indices, such as annular early diastolic velocity (Ea), isovolumic relaxation time (IVRT), pulmonary vein systolic and diastolic flow velocities, velocity propagation, left atrium area (LAA), interval between the onset of mitral E and annular Ea (TE–Ea), and Tei index were obtained. LVEDP was measured in all patients during left cardiac catheterisation. Linear correlation and multiple linear regressions were used for analysis.

Results

The mean of LVEDP was 9.9 ± 5.3 mmHg. In univariate analysis, the only significant relationship was noted with LAA (p = 0.05, R² = 0.11). However, in multivariate regression, LAA, Tei index and Ea remained in the model to predict LVEDP (p = 0.02, R² = 0.26). For prediction of LVEDP ≥ 15 mmHg, the best model consisted of LAA, IVRT and Ea, and had a sensitivity of 85% and specificity of 85%.

Conclusion

Our results provided evidence that, in patients with moderate to severe MS, LVEDP can be estimated by combining Doppler echocardiographic variables of mitral flow. However, more studies are required to confirm these results.

Transition from sinus rhythm to atrial fibrillation - a mechanism inducing or delaying pulmonary congestion and edema

Cardiogenic pulmonary edema (PEd) is a life-threatening condition where fluid accumulates in the lungs due to increasing hydrostatic pressure building up in the pulmonary vasculature (PV): veins, venules and capillaries. Atrial fibrillation (AF) is accepted as an arrhythmia which triggers and promotes the pathophysiological processes leading to pulmonary congestion and its final expression: PEd. We propose a different view, where AF is actually a physiological solution temporarily protecting from PEd. We hypothesize that the compliance of the left atrium (LA) increases with the onset of AF. Thus, it is possible that even if the volume of blood within the LA increases due to loss of atrial contraction, the pressure within the LA would still be lower than that prior to AF (because of the increased LA compliance during AF). Decreased LA pressure allows more blood to flow from the PV to the LA, abating the hydrostatic pressure buildup in the PV compartment. The ratio, R, between the LA volume gained from the transition to AF provided by the greater LA compliance, and the volume of blood retained in the LA due to loss of atrial contraction, determines the instant pressure in the LA, as AF begins. If R is >1, then the LA pressure will instantly decrease with the transition to AF and this may be beneficial in delaying PEd.

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.

High-sensitivity troponin T as a marker to predict cardiotoxicity in breast cancer patients with adjuvant trastuzumab therapy

The humanized monoclonal antibody trastuzumab has been in routine use for chemotherapy for human epidermal growth factor receptor II (HER2)-positive breast cancer. A major adverse effect of trastuzumab is cardiotoxicity. Well-established biomarkers or echocardiographic parameters to predict trastuzumab-induced cardiotoxicity have not yet been determined. We attempted to identify useful biomarkers and/or echocardiographic parameters to predict trastuzumab-induced cardiotoxicity. We prospectively investigated the cases of 19 women who received chemotherapy including anthracyclines and trastuzumab for HER2-positive breast cancer. We measured cardiac biomarkers and echocardiographic parameters before their chemotherapy and every 3 months up to 15 months until the end of the adjuvant trastuzumab therapy. We divided the patients into two groups: group R was the nine patients who showed a reduction of left ventricular ejection fraction (LVEF) ≥5%, and group N was the 10 patients who showed a reduction of LVEF <5%. The high-sensitivity troponin T (hs-TnT) level at 6 months was significantly higher in group R than in group N (11.0 ± 7.8 pg/mL vs. 4.0 ± 1.4 pg/mL, p < 0.01). The hs-TnT level with a cutoff value of 5.5 pg/mL at 6 months had 78% sensitivity and 80% specificity for predicting a reduction of LVEF at 15 months. In our evaluation of echocardiographic parameters at baseline, the diastolic function was more impaired in group R than in group N. The hs-TnT and echocardiographic parameters of diastolic function could be useful to predict trastuzumab-induced cardiotoxicity.

Usefulness of conventional and tissue Doppler echocardiography to predict congestive heart failure in dogs with myxomatous mitral valve disease

Background

Systolic and diastolic functions have been evaluated to predict outcome in congestive heart failure (CHF). Recently, tissue Doppler imaging (TDI) has become useful for the estimation of myocardial function in cardiac diseases of humans and animals.

Objective

This study was designed to assess whether myocardial function as assessed by TDI is associated with the occurrence of CHF in dogs with myxomatous mitral valve disease (MMVD) and whether additional information is gained over conventional Doppler variables.

Animals

Forty‐one privately owned dogs (15 healthy dogs and 26 dogs with MMVD) were included. Dogs with MMVD were divided into non‐CHF (n = 10) and CHF groups (n = 16).

Methods

Conventional echocardiographic examinations were performed. In addition, TDI‐derived variables, including radial and longitudinal velocities, strain, and strain rate were assessed.

Results

Several (12 of 47, 26%) conventional and tissue Doppler echocardiography variables were significant predictors of CHF in a univariate analysis (P < .05). However, TDI‐derived E/E_{m sept} was the only load‐independent significant predictor of CHF (P < .05) after multivariate logistic regression analysis. The E/E_{m sept} cut‐off value of >18.7 had a sensitivity of 56% and specificity of 90% in predicting CHF in dogs with MMVD.

Conclusions and Clinical Importance

The combination of TDI of the mitral annulus and mitral inflow velocity provided better estimates of diastolic dysfunction in dogs with MMVD and CHF. Additional study is warranted to assess TDI‐derived E/E_{m sept}, an index of diastolic function that could contribute to the management of dogs with MMVD and CHF.

Short-term outcomes after hospital discharge in patients admitted with heart failure in Abeokuta, Nigeria: data from the Abeokuta Heart Failure Registry

Background

Compared to other regions of the world, there is a paucity of data on the short-term outcome of acute heart failure (AHF) in Africa’s most populous country, Nigeria. We examined the six-month outcomes (including case fatalities) in 285 of 309 AHF subjects admitted with HF to a tertiary hospital in Abeokuta, Nigeria.

Methods

The study cohort of 285 subjects comprised 150 men (52.6%) and 135 women (47.4%) with a mean age of 56.3 ± 15.6 years and the majority in NYHA class III (75%).

Results

There were a number of differences according to the subject’s gender; men being older and more likely to present with hypertensive heart disease (with greater left ventricular mass) while also having greater systolic dysfunction. Mean length of stay was 10.5 ± 5.9 days. Mean follow up was 205 days, with 23 deaths and 20 lost to follow up. At 30 days, 4.2% (95% CI: 2.4–7.3%) had died and by 180 days this had increased to 7.5% (95% CI: 4.7–11.2%); with those subjects with pericardial disease demonstrating the highest initial mortality rate. Over the same period, 13.9% of the cohort was re-admitted at least once.

Conclusions

The characteristics of this AHF cohort in Nigeria were different from those reported in high-income countries. Cases were relatively younger and presented with non-ischaemic aetiological risk factors for HF, especially hypertensive heart disease. Moreover, mortality and re-admission rates were relatively lower, suggesting region-specific strategies are required to improve health outcomes.

Selection for atrial fibrillation ablation: Importance of diastolic function grading

BACKGROUND

Pulmonary vein isolation (PVI) has become an accepted therapy for patients with atrial fibrillation (AF) and the indications have widened to include non-paroxysmal AF-patients. Maintenance of sinus rhythm after PVI can be adversely affected by clinical or echocardiographic parameters, which should be clearly identified.

METHODS AND RESULTS

After baseline clinical and echocardiographic evaluations, PVI was performed in patients with paroxysmal or non-paroxysmal AF. The follow-up strategy after PVI included: (1) clinical follow up, 12-lead electrocardiography (ECG) and 24-h ECG every 3 months, (2) trans-telephonic ECGs twice daily and when symptomatic (over 4 weeks) every 3 months, or (3) continuous monitoring via implanted devices. A recurrence was an atrial arrhythmia lasting >30s. All 340 PVI procedures of 229 patients were analyzed. On average, 1.5 PVI procedures per patient (range, 1-6 PVI) were performed. The mean age was 58±11 years (73% male) with 109 paroxysmal and 120 non-paroxysmal AF cases. Clinical follow-up with 12-lead ECGs, 24-h ECGs, trans-telephonic ECGs, and implanted devices was complete in 100%, 63%, 51%, and 16% of cases, respectively. The overall one-year recurrence rate of 59% (range, 24-82%) was dependent on grades of diastolic function (normal - dysfunction grade III) in a multivariable analysis model. Patients with normal diastolic function had the lowest recurrence rates of 24% and 49% after 1 and 3 years of follow-up, respectively (p<0.0001).

CONCLUSION

Diastolic function could serve as a simple summary predictor for AF recurrence, and would facilitate clinical decision-making in AF treatment.

Echocardiography-derived tricuspid regurgitant jet velocity is an important marker for the progression of sickle-cell disease

BACKGROUND

Although echocardiography-derived tricuspid regurgitant jet velocity (TRV) is associated with increased mortality in sickle-cell disease (SCD), it is unclear whether increased TRV is a marker of multiorgan disease due to systemic vasculopathy or related to increased pulmonary artery systolic pressure with episodes of multiple acute chest syndrome (ACS).

METHODS

Our study analyzed 148 consecutive patients with transthoracic echocardiography with TRV data, who came to our adult SCD Clinic at the Wake Forest Baptist Medical Center. For our analysis, we took TRV ≥ 2.5 m/s as elevated. Patients were followed on average for 9 years.

RESULTS

TRV ≥ 3 m/s was significantly associated with increased mortality (p < 0.001), thromboembolism (p < 0.001), hospitalization for ACS (p < 0.001), supraventricular arrhythmia (p = 0.028), right ventricular (RV) dilation, decreased hemoglobin and increased creatinine. Patients with a progressive increase in TRV during follow-up had increased mortality (36.7 vs. 8.6%, p = 0.007) and increased ACS (45 vs. 5.7%, p < 0.001). Death was independently associated with TRV ≥ 3 m/s (p = 0.023), ACS (p = 0.001) and increased RV basal diameter (p = 0.003).

CONCLUSIONS

TRV is an important global marker for the severity and progression of SCD, and carries a significant prognostic implication.

Transthoracic ultrafast Doppler imaging of human left ventricular hemodynamic function

Heart diseases can affect intraventricular blood flow patterns. Real-time imaging of blood flow patterns is challenging because it requires both a high frame rate and a large field of view. To date, standard Doppler techniques can only perform blood flow estimation with high temporal resolution within small regions of interest. In this work, we used ultrafast imaging to map in 2-D human left ventricular blood flow patterns during the whole cardiac cycle. Cylindrical waves were transmitted at 4800 Hz with a transthoracic phased-array probe to achieve ultrafast Doppler imaging of the left ventricle. The high spatio-temporal sampling of ultrafast imaging permits reliance on a much more effective wall filtering and increased sensitivity when mapping blood flow patterns during the pre-ejection, ejection, early diastole, diastasis, and late diastole phases of the heart cycle. The superior sensitivity and temporal resolution of ultrafast Doppler imaging makes it a promising tool for the noninvasive study of intraventricular hemodynamic function.

Implication of left ventricular diastolic dysfunction in cryptogenic ischemic stroke

BACKGROUND AND PURPOSE

Left ventricular diastolic dysfunction (LVDD) is a predictor for atrial fibrillation (AF). This study was aimed to investigate whether LVDD in cryptogenic ischemic stroke (CS) could be a clue to stroke mechanism.

METHODS

The clinical and echocardiographic findings of 1589 consecutive patients with acute ischemic stroke or transient ischemic attack between 2004 and 2013 were reviewed. LVDDs among stroke subtypes were graded by transthoracic echocardiography into 4 groups by severity: normal, abnormal relaxation (grade I), pseudonormal (grade II), and restrictive diastolic filling (grade III), whereas severe LVDD was defined as grade III. We classified the lesion pattern of CS into cardioembolism-mimic or non-cardioembolism-mimic and determined whether cardioembolism-mimic lesions were associated with severe LVDD.

RESULTS

The fraction of severe LVDD in CS was not different from that of stroke with AF (27.3% versus 37.1%; P=0.173) but was significantly higher than that of stroke without AF (27.3% versus 13.4%; P=0.008). Cardioembolism-mimic CS had more severe LVDD than non-cardioembolism-mimic CS (41.4% versus 11.5%; P=0.013). LVDD of grade II (odds ratio, 4.37; 95% confidence interval, 2.99-6.41) and grade III (odds ratio, 5.60; 95% confidence interval, 3.42-9.17) were independently related to stroke with AF after adjusting covariates.

CONCLUSIONS

The severe LVDD could be a predictor of stroke with AF, and its frequency was similar between CS and stroke with AF. Cardioembolism-mimic CS had significantly more severe LVDD than non-cardioembolism-mimic CS. LVDD could be helpful to discriminate the stroke mechanism in the patients with acute CS.

Patterns of late gadolinium enhancement in Duchenne muscular dystrophy carriers

BACKGROUND

This study was designed to assess whether cardiovascular magnetic resonance imaging (CMR) in Duchenne muscular dystrophy carriers (DMDc) may index any cell milieu elements of LV dysfunction and whether this cardiac phenotype may be related to genotype. The null hypothesis was that myocardial fibrosis, assessed by late gadolinium enhancement (LGE), might be similarly accounted for in DMDc and gender and age-matched controls.

METHODS

Thirty DMDc patients had CMR and genotyping with 37 gender and age-matched controls. Systolic and diastolic LV function was assessed by 2D-echocardiography.

RESULTS

Absolute and percent LGE were higher in muscular symptomatic (sym) than asymptomatic (asy) DMDc (1.77 ± 0.27 vs 0.76 ± 0.17 ml; F = 19.6, p < 0.0001 and 1.86 ± 0.26% vs 0.68 ± 0.17%, F = 22.1, p < 0.0001, respectively). There was no correlation between LGE and age. LGE was seen most frequently in segments 5 and 6; segment 5 was involved in all asy-DMDc. Subepicardial LGE predominated, compared to the mid-myocardial one (11 out of 14 DMDc). LGE was absent in the subendocardium. No correlations were seen between genotyping (type of mutation, gene region and protein domain), confined to the exon's study, and cardiac phenotype.

CONCLUSIONS

A typical myocardial LGE-pattern location (LV segments 5 and 6) was a common finding in DMDc. LGE was more frequently subepicardial plus midmyocardial in sym-DMDc, with normal LV systolic and diastolic function. No genotype-phenothype correlation was found.

The effect of age on right ventricular diastolic function in healthy subjects undergoing treadmill exercise test

OBJECTIVE

There is an increasing interest for the value of right ventricle (RV) in predicting exercise tolerance and prognosis in cardiovascular disease. However, there is relatively few data evaluating the effect of age on RV diastolic filling velocities during rest or exercise in healthy subjects.

METHODS

A total of 54 healthy subjects were enrolled in this study. Patients were divided into 2 groups according to their age: Group 1 (≤45-years-old) and Group 2 (>45-years-old). A treadmill exercise test was performed using modified Bruce protocol. Conventional pulsed-wave Doppler and tissue Doppler velocities were obtained both at rest and immediately after the end of exercise, respectively.

RESULTS

In the overall analysis, tricuspid flow Doppler analysis showed a significant increase in A-wave velocity, less marked rise in E-wave velocity, decreased E/A ratio and decreased E-wave deceleration time (EDT) with exercise. Tissue Doppler analysis revealed increased Aa velocity, decreased in Ea/Aa ratio and IVRT. No significant change was observed in Ea velocity and E/Ea ratio with exercise. Although diastolic velocities changed significantly with exercise, systolic velocities did not. Cardiac response to exercise differed slightly in the older subjects compared to younger ones. The older subjects were more likely to have a reduced mean rate of RV filling for the second half of diastole from baseline to peak exercise.

CONCLUSION

To distinguish normal physiological changes due to aging from those of pathologic conditions may provide benefits while evaluating patients with known or suspected cardiovascular disease.

Decreased aorto-septal angle may contribute to left ventricular diastolic dysfunction in healthy subjects

BACKGROUND

Left ventricular (LV) diastolic dysfunction is often observed in healthy older subjects without structural heart disease, although its exact mechanisms have not been established. A decrease in the aorto-septal angle (ASA), an alteration of LV shape due to aortic elongation, is also frequently seen in elderly subjects. The objective of this study was to evaluate whether it can contribute to LV diastolic dysfunction in healthy subjects.

METHODS

Echocardiography was performed in 77 healthy subjects (42 men, mean age 43.2 ± 13.8 years) to measure the ASA, early diastolic transmitral flow velocity (E), isovolumic relaxation time (IRT), and early diastolic mitral annular velocity (e'). The LV peak early diastolic longitudinal strain rate (GSRE ) was measured using a two-dimensional speckle tracking imaging technique.

RESULTS

ASA was significantly correlated with E (r = 0.54, p < 0.001), IRT (r = -0.41, p < 0.001), e' (r = 0.57, p < 0.001), and GSRE (r = 0.63, p < 0.001) and shown by stepwise multivariate analysis to be the strongest independent determinant of E, IRT, and GSRE , and one of the independent determinants of e'.

CONCLUSIONS

The alteration of LV shape associated with reduced ASA may be one of the causes of LV diastolic dysfunction independently of age in otherwise healthy subjects.

High-sensitivity troponin I and amino-terminal pro--B-type natriuretic peptide predict heart failure and mortality in the general population

INTRODUCTION

High-sensitivity cardiac troponin assays have potent prognostic value in stable cardiovascular disease cohorts. Our objective was to assess the prognostic utility of a novel cardiac troponin I (cTnI) high-sensitivity assay, independently and in combination with amino-terminal pro-B-type natriuretic peptide (NT-proBNP), for the future development of heart failure and mortality in the general community.

METHODS

A well-characterized community-based cohort of 2042 participants underwent clinical assessment and echocardiographic evaluation. Baseline measurements of cTnI with a high-sensitivity assay and NT-proBNP were obtained in 1843 individuals. Participants were followed for new-onset heart failure and mortality with median (25th, 75th percentile) follow-up of 10.7 (7.9, 11.6) and 12.1 (10.4, 13.0) years, respectively.

RESULTS

When measured with a high-sensitivity assay, cTnI greater than the sex-specific 80th percentile was independently predictive of heart failure [hazard ratio 2.56 (95% confidence interval 1.88-3.50), P < 0.001] and mortality [1.91(1.49-2.46), P < 0.001] beyond conventional risk factors in this community-based cohort, with significant increases in the net reclassification improvement for heart failure. The prognostic utility of cTnI measured with a high-sensitivity assay goes beyond NT-proBNP, yet our data suggest that these 2 assays are complementary and most beneficial when evaluated together in identifying at-risk individuals in the community.

CONCLUSIONS

Our findings lay the foundation for prospective studies aimed at identification of individuals at high risk by use of a multimarker approach, followed by aggressive prevention strategies to prevent subsequent heart failure.

Cardiac ultrasound and abdominal compartment syndrome

This review focuses on the available literature published about the evaluation of haemodynamic consequences of the abdominal compartment syndrome (ACS). Animal and clinical studies described decreased venous return, systemic vasoconstriction, systolic and diastolic dysfunction of left and right ventricles. Doppler echocardiography is a non-invasive bedside procedure which provides a complete haemodynamic evaluation of patients with ACS. Despite numerous evaluations in anesthesia during laparoscopic surgery, the use of echocardiography remains scarce in critically ill patients with ACS.

Clinical impact of diastolic function after surgical ventricular restoration

OBJECTIVE

The impact of diastolic function on the clinical outcome of surgical ventricular restoration remains controversial.

METHODS

71 patients undergoing surgical ventricular restoration between 1999 and 2012 were investigated. Perioperative echocardiographic parameters were compared, risk factors for deaths and cardiac events were analyzed, and actuarial freedom from death and cardiac events was computed.

RESULTS

Preoperatively, the left ventricular end-systolic volume index was 77 ± 40 mL·m(-2) and left ventricular ejection fraction was 33% ± 11%. Postoperatively, left ventricular systolic function was significantly improved (end-systolic volume index 49 ± 31 mL·m(-2), ejection fraction 42.1% ± 11.7%) with a 33.8% ± 21.9% reduction in left ventricular end-systolic volume index. The transmitral filling deceleration time decreased from 198 ± 54 to 150 ± 46 ms, and the ratio of early peak filling velocities increased significantly postoperatively (from 16 ± 10 to 21 ± 17). Freedom from death and cardiac events at 5 years was 78% ± 5% and 64% ± 6%, respectively. Multivariate analyses revealed that age was a significant risk factor for all-cause death, postoperative transmitral inflow pattern for cardiac death, and preoperative mitral regurgitation and postoperative transmitral inflow pattern for cardiac events.

CONCLUSION

Despite its positive impact on systolic function, surgical ventricular restoration negatively affects postoperative diastolic function. Postoperative severe diastolic dysfunction may correlate with late mortality and cardiac events.

Characterization of aging-associated cardiac diastolic dysfunction

AIMS

Diastolic dysfunction is common in geriatric heart failure. A reliable parameter to predict myocardium stiffness and relaxation under similar end-diastolic pressure is being developed. We propose a material and mathematical model for calculating myocardium stiffness based on the concept of linear correlation between [Formula: see text] and wedge pressure.

METHODS AND RESULTS

We enrolled 919 patients (male: [Formula: see text][Formula: see text]). Compared with the younger population of controls (mean age: [Formula: see text] years; [Formula: see text]; male: [Formula: see text] [Formula: see text]), the elderly (mean age: [Formula: see text]; [Formula: see text]; male: [Formula: see text] [Formula: see text]) had a greater prevalence of hypertension, diabetes mellitus, and coronary artery disease (all [Formula: see text]). We collected their M-mode and 2-D echocardiographic volumetric parameters, intraventricular filling pressure, and speckle tracking images to establish a mathematical model. The feasibility of this model was validated. The average early diastolic velocity of the mitral annulus assessed using tissue Doppler imaging was significantly attenuated in the elderly ([Formula: see text]: [Formula: see text] vs. [Formula: see text]; [Formula: see text]) and corresponded to the higher estimated wedge ([Formula: see text]) pressure ([Formula: see text] vs. [Formula: see text]; [Formula: see text]) in that cohort. E (Young's modulus) was calculated to describe the tensile elasticity of the myocardium. With the same intraventricular filling pressure, E was significantly higher in the elderly, especially those with [Formula: see text] values [Formula: see text]. Compared with diastolic dysfunction parameters, E also presented sentinel characteristics more sensitive for detecting early myocardial relaxation impairment, which indicates stiffer myocardium in aging hearts.

CONCLUSION

Our material and geometric mathematical model successfully described the stiffer myocardium in aging hearts with higher intraventricular pressure. Additional studies that compare individual differences, especially in health status, are needed to validate its application for detecting diastolic heart failure.

Tissue doppler myocardial performance index in patients with heart failure and its relationship with haemodynamic parameters

The myocardial performance index (MPI) reflects both the systolic and diastolic function of the heart, and is easily applied in practice. In this study, we aimed to determine the relationship between MPI and invasive haemodynamic parameters in heart failure patients. A total of 126 patients with heart failure were selected, all of whom were referred for diagnostic cardiac catheterisation, and were divided into two groups. Group I consisted of 59 patients (32 men and 27 women, mean age 61 ± 10; functional capacity New York Heart Association (NYHA) Class I; and left ventricular end-diastolic pressure (LVEDP) <16 mmHg). Group II included 67 patients (34 men and 33 women, mean age 60 ± 9; NYHA Class ≥ II; LVEDP ≥ 16 mmHg). The following parameters were measured in all patients: ejection fraction with Simpson method, the peak mitral early (E) and late (A) diastolic velocities, E/A ratio, deceleration time (DT) and tissue Doppler from four different areas of the mitral annulus (septum, lateral, inferior and anterior). In order to measure MPI with two methods (standard Doppler and tissue Doppler), isovolumetric contraction time (IVCT), isovolumetric relaxation time (IVRT) and ejection time (ET) were measured from four areas and mean values of MPI were calculated. There was no difference between the two groups in E/A ratios, DT and IVRT (p > 0.05). Group II patients had longer IVCT and ET, when compared with group I patients (p < 0.05). MPI, measured by both standard pulsed wave Doppler and tissue Doppler methods, was significantly higher in group II patients, when compared with the values obtained from group I patients (Group I: 0.50 ± 0.2 and 0.50 ± 0.14; group II: 0.98 ± 0.3 and 1.2 ± 0.32; p < 0.001). According to receiver operating characteristics curve analysis, the cut-off value for MPI measured by tissue Doppler was 0.74. The sensitivity and specificity of this value were measured as 92.5 and 91.5%, respectively. MPI measured by standard Doppler method was 0.67, and its sensitivity and specificity were 85.1 and 83.1%, respectively. We found a strong relationship between MPI and LVEDP (r = 0.83, p < 0.001; r = 0.96, p < 0.001), especially when measured by tissue Doppler. In addition, we observed a significant relationship between the MPI values measured by tissue Doppler and those measured by standard traditional methods (r = 0.85, p < 0.001). We showed that MPI was reliable for the evaluation of global cardiac functions in patients with heart failure, as measured with both pulsed-wave Doppler and tissue Doppler. We assert that, in order to differentiate between those patients with symptomatic heart failure from the asymptomatic cases, MPI as measured with the tissue Doppler method is an improvement on MPI as measured using traditional methods.

Analysis of left atrial performance in patients with type 2 diabetes mellitus without overt cardiac disease and inducible ischemia: high prevalence of increased systolic force related to enhanced left ventricular systolic longitudinal function

OBJECTIVES

In patients with chronic pressure overload, higher left atrial systolic force (LASF) is associated with high-risk cardiovascular (CV) phenotype, with increased left ventricular (LV) mass, concentric hypertrophy, and diastolic dysfunction. In hypertension and aortic stenosis, LASF predicts increased rate of CV events independent of traditional risk factors. Moreover, LASF is an independent predictor of heart failure in diabetic and nondiabetic patients. Limited data are available about LASF and its relationship with LV systolic function in type 2 diabetes mellitus (T2DM).

METHODS

We used baseline clinic and echocardiographic data from 333 patients recruited in the SHORTWAVE study evaluating LV and left atrial performance in T2DM patients without cardiac disease. LASF was calculated by Manning's method and defined high when exceeded 16 Kdynes (90th percentile of LASF found in 120 healthy subjects used as controls).

RESULTS

Mean LASF was 15.8 Â ± 9.4 Kdynes/cm(2) and showed a close positive correlation with peak mitral annular systolic velocity (function of LV longitudinal fibers), independent of E/E', age, systolic blood pressure, heart rate, and concentric geometry (multiple R = 0.57, P < 0.0001). Such independent correlation (tested in patients with and without concomitant hypertension) was confirmed at multiple logistic regression analysis where patients were dichotomized for having high (119 = 36%) or normal LASF.

CONCLUSIONS

High LASF is present in one third of T2DM patients without overt cardiac disease and is positively and independently related to an increased LV longitudinal shortening function, suggesting a close interaction between LV systolic and diastolic function.

Association of cardiorespiratory fitness with left ventricular remodeling and diastolic function: the Cooper Center Longitudinal Study

OBJECTIVES

This study sought to compare the cross-sectional associations between fitness and echocardiographic measures of cardiac structure and function.

BACKGROUND

Cardiorespiratory fitness is inversely associated with heart failure risk. However, the mechanism through which fitness lowers heart failure risk is not fully understood.

METHODS

We included 1,678 men and 1,247 women from the Cooper Center Longitudinal Study who received an echocardiogram from 1999 to 2011. Fitness was estimated by Balke protocol (in metabolic equivalents) and also categorized into age-specific quartiles, with quartile 1 representing low fitness. Cross-sectional associations between fitness (in metabolic equivalents) and relative wall thickness, left ventricular end-diastolic diameter indexed to body surface area, left atrial volume indexed to body surface area, left ventricular systolic function, and E/e' ratio were determined using multivariable linear regression analysis.

RESULTS

Higher levels of mid-life fitness (metabolic equivalents) were associated with larger indexed left atrial volume (men: beta = 0.769, p < 0.0001; women: beta = 0.879, p value ≤0.0001) and indexed left ventricular end-diastolic diameter (men: beta = 0.231, p < 0.001; women: beta = 0.264, p < 0.0001). Similarly, a higher level of fitness was associated with a smaller relative wall thickness (men: beta = -0.002, p = 0.04; women: beta = -0.005, p < 0.0001) and E/e' ratio (men: beta = -0.11, p = 0.003; women: beta = -0.13, p = 0.01). However, there was no association between low fitness and left ventricular systolic function (p = NS).

CONCLUSIONS

Low fitness is associated with a higher prevalence of concentric remodeling and diastolic dysfunction, suggesting that exercise may lower heart failure risk through its effect on favorable cardiac remodeling and improved diastolic function.

Contemporary profile of acute heart failure in Southern Nigeria: data from the Abeokuta Heart Failure Clinical Registry

OBJECTIVES

The aim of this study was to determine the contemporary profile, clinical characteristics, and intrahospital outcomes of acute heart failure (AHF) in an African urban community.

BACKGROUND

There are limited data on the current burden and characteristics of AHF in Nigerian Africans.

METHODS

Comprehensive and detailed clinical and sociodemographic data were prospectively collected from 452 consecutive patients presenting with AHF to the only tertiary hospital in Abeokuta, Nigeria (population about 1 million) over a 2-year period.

RESULTS

The mean age was 56.6 ± 15.3 years (57.3 ± 13.4 years for men, 55.7 ± 17.1 years for women), and 204 patients (45.1%) were women. Overall, 415 subjects (91.8%) presented with de novo AHF. The most common risk factor for heart failure was hypertension (pre-existing in 64.3% of patients). Type 2 diabetes mellitus was present in 41 patients (10.0%). Hypertensive heart failure was the most common etiological cause of heart failure, responsible for 78.5% of cases. Dilated cardiomyopathy (7.5%), cor pulmonale (4.4%), pericardial disease (3.3%), rheumatic heart disease (2.4%), and ischemic heart disease were less common (0.4%) causes. The majority of subjects (71.2%) presented with left ventricular dysfunction (mean left ventricular ejection fraction 43.9 ± 9.0%), with valvular dysfunction and abnormal left ventricular geometry frequently documented. The mean duration of hospital stay was 11.4 ± 9.1 days, and intrahospital mortality was 3.8%.

CONCLUSIONS

Compared with those in high-income countries, patients presenting with AHF in Abeokuta, Nigeria, are relatively younger and still of working age. It is also more common in men and associated with severe symptoms because of late presentation. Intrahospital mortality is similar to that in other parts of the world.

The isovolumic relaxation to early rapid filling relation: kinematic model based prediction with in vivo validation

Although catheterization is the gold standard, Doppler echocardiography is the preferred diastolic function (DF) characterization method. The physiology of diastole requires continuity of left ventricular pressure (LVP)‐generating forces before and after mitral valve opening (MVO). Correlations between isovolumic relaxation (IVR) indexes such as tau (time‐constant of IVR) and noninvasive, Doppler E‐wave‐derived metrics, such as peak A‐V gradient or deceleration time (DT), have been established. However, what has been missing is the model‐predicted causal link that connects isovolumic relaxation (IVR) to suction‐initiated filling (E‐wave). The physiology requires that model‐predicted terminal force of IVR (F_tIVR) and model‐predicted initial force of early rapid filling (F_{i E‐wave}) after MVO be correlated. For validation, simultaneous (conductance catheter) P‐V and E‐wave data from 20 subjects (mean age 57 years, 13 men) having normal LV ejection fraction (LVEF>50%) and a physiologic range of LV end‐diastolic pressure (LVEDP) were analyzed. For each cardiac cycle, the previously validated kinematic (Chung) model for isovolumic pressure decay and the Parametrized Diastolic Filling (PDF) kinematic model for the subsequent E‐wave provided F_tIVR and F_{i E‐wave} respectively. For all 20 subjects (15 beats/subject, 308 beats), linear regression yielded F_tIVR = α F_{i E‐wave} + b (R = 0.80), where α = 1.62 and b = 1.32. We conclude that model‐based analysis of IVR and of the E‐wave elucidates DF mechanisms common to both. The observed in vivo relationship provides novel insight into diastole itself and the model‐based causal mechanistic relationship that couples IVR to early rapid filling.