Echocardiographic assessment of diastolic function

Predictors and Clinical Impacts of Aggravated Left Ventricular Diastolic Dysfunction After Off-Pump Coronary Artery Bypass Grafting

BACKGROUND

To determine the predictors of aggravated left ventricular diastolic dysfunction (LVDD) in patients undergoing off-pump coronary artery bypass grafting (OPCAB) and to compare late outcomes according to the aggravated LVDD.

METHODS AND RESULTS

OPCAB was performed in 1,101 patients (2001-2013). LVDD was classified as normal, mild, moderate or severe. Patients were divided into 2 groups: non-aggravated LVDD (group I) and aggravated LVDD (group II). The primary endpoint was aggravation of LVDD. The secondary endpoint was late mortality and morbidity such as major adverse cardiac and cerebrovascular events (MACCE) related to LVDD aggravation postoperatively. There were 894 patients in group I and 207 in group II. Multivariate analysis revealed that preoperative peripheral artery obstructive disease (PAOD) (P=0.04), renal failure (P<0.01), and A' velocity (P<0.01) anticipated aggravated LVDD. The Cox hazards model revealed that aggravated LVDD was a poor prognostic factor for MACCE (P<0.01) and overall survival (P<0.01). The Kaplan-Meier survival curve showed that aggravated LVDD was related to poor late outcomes (freedom from MACCE, P=0.01; overall survival, P<0.01).

CONCLUSIONS

Aggravated LVDD significantly affects late clinical outcomes after OPCAB and preoperative PAOD, renal failure, and A' velocity might be predictors. (Circ J 2016; 80: 1937-1945).

Echocardiography in the Assessment of Left Atrial Pressure After Pediatric Heart Surgery: A Comparison Study With Measurements Obtained From Left Atrial Catheter

BACKGROUND

Correlation between ventricular end-diastolic pressure and pulsed Doppler and tissue Doppler-derived E/e' ratio has been widely reported in adults but scarcely studied in children with congenital heart diseases. This ratio is defined as the relationship between diastolic transmitral flow velocity (cm/s; E) and myocardial diastolic relaxation velocity (cm/s; e') in the lateral aspect of the mitral annulus. Our main objective was to ascertain whether a correlation existed between direct measurement of left atrial pressure and echocardiographic E/e' ratio in children after heart surgery.

METHODS

Prospective study including 27 consecutive children after pediatric heart surgery. Data were analyzed according to whether they were obtained within the first 72 hours following surgery or later on. Sensitivity, specificity, positive and negative predictive values, and areas under the receiver-operating characteristics curve of E/e' ratio in detection of left atrial pressure values ≥13 mm Hg were evaluated.

RESULTS

Forty-eight studies were conducted in 27 patients. Thirty-two studies were performed during the first 72 hours after heart surgery and 16 beyond the third day. Median patient age was 0.82 years (5 days-16 years). Median left atrial pressure values and E/e' measurements of the whole cohort (N = 48) were 12.0 and 10.2, respectively. Intraclass correlation index between left atrial pressure values and echocardiographic E/e' ratio was 0.35, 0.25 for studies performed within 72 hours, but 0.78 (P < .01) for those performed later. There was also a high positive predictive value, since in 13 (87%) of 15 studies with an E/e' ratio ≥13, the left atrial pressure was ≥13 mm Hg.

CONCLUSION

While echocardiographic E/e' ratio did not show a good correlation with left atrial pressure in the immediate postoperative period, the positive predictive value may suffice to aid clinicians in predicting elevated pressures.

Changes in left atrial deformation in hypertrophic cardiomyopathy: Evaluation by vector velocity imaging

Abstract:Objectives: Hypertrophic cardiomyopathy (HCM) represents a generalized myopathic process affecting both ventricular and atrial myocardium. We assessed the global and regional left atrial (LA) function and its relation to left ventricular (LV) mechanics and clinical status in patients with HCM using Vector Velocity Imaging (VVI). Methods: VVI of the LA and LV was acquired from apical four- and two-chamber views of 108 HCM patients (age 40 ± 19years, 56.5% men) and 33 healthy subjects, all had normal LV systolic function. The LA subendocardium was traced to obtain atrial volumes, ejection fraction, velocities, and strain (ϵ)/strain rate (SR) measurements. Results: Left atrial reservoir (ϵ_sys,SR_sys) and conduit (early diastolic SR_e) function were significantly reduced in HCM compared to controls (P < .0001). Left atrial deformation directly correlated to LVϵ_sys, SR_sys and negatively correlated to age, NYHA class, left ventricular outflow tract (LVOT) gradient, left ventricular mass index (LVMI), LA volume index and severity of mitral regurge (P < 0.001). Receiver operating characterist was constructed to explore the cutoff value of LA deformation in differentiation of LA dysfunction; ϵ_sys < 40% was 75% sensitive, 50% specific, SR_sys < 1.7s^− 1 was 70% sensitive, 61% specific, SR_e> − 1.8s^− 1 was 81% sensitive and 30% specific, SR_a> − 1.5s^− 1 was 73% sensitive and 40% specific. By multivariate analysis global LVϵ_sys and LV septal thickness are independent predictors for LAϵ_sys, while end systolic diameter is the only independent predictor for SR_sys, P < .001. Conclusion: Left atrial reservoir and conduit function as measured by VVI were significantly impaired while contractile function was preserved among HCM patients. Left atrial deformation was greatly influenced by LV mechanics and correlated to severity of phenotype.

Relation between heavy metals and left ventricular diastolic function in patients with coronary artery disease

One of the earliest detectable abnormalities in patients with coronary artery disease is left ventricular diastolic dysfunction. Its main cause is myocardial ischaemia, but still many of other mechanisms are possible. The aim of this study was to investigate the relation of cadmium, lead, copper, zinc, and selenium with left ventricular diastolic function indices in patients with coronary artery disease. The study included 33 patients (14 with single-vessel disease and 19 with multivessel disease on angiography) who were not exposed occupationally to heavy metals. Control group consisted of 18 patients with normal coronary arteries. The blood cadmium and lead concentrations and serum zinc, selenium and copper concentrations were determined using atomic absorption spectrophotometry. Left ventricular diastolic function parameters were estimated by echo-Doppler and colour M-mode. All heavy metal concentrations were within the standard ranges in all studied groups. Patients with single-vessel disease, multivessel disease and control group did not differ in concentrations of studied metals. On univariate and multivariate analysis only cadmium significantly correlated with echocardiographic parameters of left ventricular diastolic function: peak early to peak late mitral inflow velocity ratio (r = -0.36, p < 0.05) and deceleration time of early mitral inflow (r = 0.43, p < 0.01) in patients with CAD. No significant correlations between concentrations of heavy metals and indices of left ventricular diastolic function were found in control group. The present data suggest that cadmium in concentrations even below the threshold limit value for unexposed population may contribute to development of left ventricular diastolic dysfunction in patients with CAD, potentializing the effect of myocardial ischaemia.

Spongious Hypertrophic Cardiomyopathy in Patients With Mutations in the Four-and-a-Half LIM Domain 1 Gene

Background—

X-linked myopathy with postural muscle atrophy is a novel X-linked myopathy caused by mutations in the four-and-a-half LIM domain 1 gene (FHL1). Cardiac involvement was suspected in initial publications. We now systematically analyzed the association of the FHL1 genotype with the cardiac phenotype to establish a potential cardiac involvement in the disease.

Methods and Results—

Seventeen male patients and 23 female mutation carriers were compared with healthy controls. Every patient underwent a comprehensive clinical and cardiovascular workup. ECG abnormalities occurred frequently in affected males and were less frequent in heterozygous females. Both male and female mutation carriers had increased myocardial mass (affected males=115.1±25.3 g/m 2 ; heterozygous females=95.1±19.6 g/m 2 ; controls=89.0±15.6 g/m 2 and 72.6±12.6 g/m 2 ; respectively) with increased wall thickness (typically midventricular and apical segments) mainly in affected males. Longitudinal systolic function was reduced in affected males (radial systolic strain: affected males=24.6±11.8%; male controls=43.2±14.8%; P =0.002). Diastolic dysfunction occurred in both affected males and heterozygous females. Cardiac MRI revealed a morphological hallmark of X-linked myopathy with postural muscle atrophy; a characteristic spongious structure and replacement fibrosis indicated by late enhancement could be detected in most affected males. X-linked myopathy with postural muscle atrophy was associated with reduced exercise capacity in affected males but not in heterozygous female mutation carriers.

Conclusions—

X-linked myopathy with postural muscle atrophy patients consistently showed electrical, functional, and characteristic morphological cardiac abnormalities that translate into reduced exercise capacity. Reduced systolic and diastolic function is associated with a novel type of spongious hypertrophic cardiomyopathy. An unexpected finding was that some cardiac abnormalities were also present in heterozygous female mutation carriers.

How to diagnose cardiac amyloidosis early: impact of ECG, tissue Doppler echocardiography, and myocardial biopsy

AIMS

To detect cardiac amyloidosis (CA) earlier, it is inevitable to improve diagnostic strategies.

METHODS AND RESULTS

The impact of ECG, echocardiography including tissue Doppler imaging (TDI) and strain, and myocardial biopsies was evaluated in 30 patients (63% (n = 19) men, mean age 66 +/- 8 years, NYHA 3.0 +/- 0.5, 73% with prior myocardial decompensation), in whom we proved CA. Amyloid was confirmed by apple-green birefringence under polarised light, and the causing protein by immunohistochemical examinations. Genetic analyses excluded familial CA. All patients (AL-lambda (n = 22), AL-kappa (n = 3), senile amyloidosis (n = 5)) had echocardiographic signs of restrictive cardiomyopathy (RCM), typical TDI and strain parameters (E'septal; E' lateral < 8 cm/s; E/E' > 8; S' < or =9 cm/s; global longitudinal strain (GLS) -7.9 +/- 3.8%). Pericardial effusions were present in 63% of patients. ECGs were suspicious in many patients: 19 (63%) had low-voltage, 23 (77%) reduced R waves in V(1)-V(4), and 57% both. Abnormalities, retrospectively had been present for 0.5-4 years. Twenty (67%) patients died 232 +/- 268 [2-1020] days after CA was diagnosed, but 502 +/- 333 [30-1440] days after the first symptom.

CONCLUSION

Accurate ECG evaluations, careful echocardiographic search for RCM, reduced strain/strain rates, and general indications to myocardial biopsies with correct analyses are needed to diagnose CA.

[Left ventricular diastolic dysfunction. Implications for anesthesia and critical care]

Over the last two decades there has been a growing recognition that cardiac function is not solely determined by systolic but also essentially by diastolic function. Left ventricular diastolic dysfunction is characterized by an impairment of ventricular filling caused either by abnormal relaxation, an active energy consuming process or decreased compliance, which is determined by passive tissue properties of the ventricle. Doppler echocardiography, including tissue Doppler imaging, has emerged as the preferred clinical tool for the assessment of left ventricular diastolic function. Recently the importance of left ventricular diastolic function is increasingly being recognized also during the perioperative period. Newer studies have shown that after cardiopulmonary bypass there is a significant decrease in left ventricular compliance. Experimental studies have demonstrated that sepsis is associated with a decrease in both active relaxation and ventricular compliance. Initial studies are also focusing on therapeutic options for patients with isolated diastolic dysfunction.

Future potential of echocardiography in heart failure

Echocardiography represents a convenient, portable and noninvasive method to provide important anatomic and physiologic information to inform the management of heart failure patients. Traditional echo assessments include diagnostic, etiologic and prognostic data from ventricular size, geometry and performance. Newer echocardiographic techniques are receiving greater utilization, however, and promise to further enhance diagnostic abilities in heart failure. This article reviews traditional anatomic assessments, echo-based cardiac hemodynamics, 3D echocardiography, quantification of myocardial tissue mechanics and hand-carried echocardiography. These developments in echocardiography underlie future trends toward echo objectivity, improved imaging of patients with poor acoustic windows, miniaturization and simplicity in focused exams and the expanded application of old and new techniques.

Risk scores do not predict high mortality after coronary artery bypass surgery in the presence of diastolic dysfunction

BACKGROUND

Although global postoperative mortality after on-pump coronary artery bypass grafting is approximately 3%, in some groups it can be considerably higher. Many conditions are known to increase mortality and have been included in well-known scoring systems; however, left ventricular diastolic dysfunction has not been sufficiently evaluated to identify its predictive value for mortality after coronary artery bypass grafting, nor is it integrated in currently used risk scores.

METHODS

Left ventricular filling pattern was prospectively evaluated in 191 patients scheduled for on-pump coronary artery bypass grafting. A follow-up of survival and complications was made for 30 days postoperatively. Observed mortality was compared with the mortality predicted by the scores of EuroSCORE and Parsonnet.

RESULTS

A correlation was found between diastolic function, the presence of comorbidities, and postoperative survival. There was no mortality in the group with normal filling pattern (0 of 33 patients). In the presence of an alteration of relaxation, mortality was 5 of 129 patients (3.8%); in the pseudonormal group it was 2 of 16 patients (12.5%); and in the restrictive group it was 6 of 13 patients (46.1%; p < 0.01). Parsonnet and EuroSCORE predicted a mortality of 1.5% to 1.6%, 1.5% to 2.0%, 1.5% to 2.2%, and 3.9% to 4.1% for each group, respectively. Mortality in the group with E deceleration time of 150 ms or greater was 2.8% and in the group with E deceleration time less than 150 ms was 17.3% (p < 0.01). Postoperative complications were also more frequent in the group with advanced dysfunction.

CONCLUSIONS

Severe diastolic dysfunction is a strong predictor of adverse outcome and mortality after on-pump coronary artery bypass grafting, and this high risk is not adequately predicted by EuroSCORE and Parsonnet score. Measures of diastolic function should be included in routine preoperative risk assessment.

Diastolic Function: A Sonographer’s Approach to the Essential Echocardiographic Measurements of Left Ventricular Diastolic Function

Noninvasive assessment of left ventricular filling pressures by echocardiography has been validated by invasive hemodynamic studies and correlated with clinical findings. A comprehensive echocardiographic examination based on the referral diagnosis and patient symptomatology routinely includes efforts to measure specific parameters of left ventricular diastolic function. We provide a step-by-step approach to goal-directed echocardiographic assessment of diastolic function.

Amount of left ventricular hypertrophy determines the plasma N-terminal pro-brain natriuretic peptide level in patients with hypertrophic cardiomyopathy and normal left ventricular ejection fraction

BACKGROUND

N-terminal pro-brain natriuretic peptide (NT-proBNP) is increased in patients with hypertrophic cardiomyopathy (HCM); however, the determinants of NT-proBNP level have not been clarified in HCM.

HYPOTHESIS

This study was performed to determine the relationship between NT-proBNP levels and various echocardiographic variables of patients with HCM and normal left ventricular ejection fraction (LVEF).

METHODS

We assessed plasma NT-proBNP levels and echocardiographic variables of 36 patients (19 men, 58 +/- 14 years) with HCM and an LVEF of > or = 55%. Echocardiographic variables measured were LV wall thickness, end-diastolic LV internal dimension (LVIDd) and volume (LVEDV), LV mass, and LV mass index (LV mass/body surface area, LVMI). Left ventricular outflow tract pressure gradient, transmitral E and A velocities, deceleration time (DT) of the transmitral E wave, and septal annular E' velocity were measured by Doppler technique. The relationship between echocardiographic variables and plasma NT-proBNP level was analyzed.

RESULTS

The plasma NT-proBNP level was 775.2 +/- 994.2 pg/ml (range 33.1-4729.0 pg/ml). It showed positive correlations with LV end-diastolic septal thickness (r = 0.39, p = 0.010) and LVMI (r = 0.27, p = 0.050), while it revealed negative correlations with LVIDd (r = -0.44, p = 0.004), LVEDV (r = -0.44, p = 0.004) and DT(r = -0.31,p = 0.034). The NT-proBNP level was higher in the patients with than in those without LV diastolic dysfunction (p = 0.033) and was independently related to LVIDd (p = 0.001), LVMI (p = 0.006) and DT (p = 0.031) by multivariate analysis.

CONCLUSION

In patients with HCM and normal LVEF, the amount of LV hypertrophy and LV diastolic dysfunction may exert a significant role in determining plasma NT-proBNP level.

Mitral annular myocardial velocity assessment of segmental left ventricular diastolic function after prolonged exercise in humans

We assessed segmental and global left ventricular (LV) diastolic function via tissue-Doppler imaging (TDI) as well as Doppler flow variables before and after a marathon race to extend our knowledge of exercise-induced changes in cardiac function. Twenty-nine subjects (age 18-62 year) volunteered to participate and were assessed pre- and post-race. Measurements of longitudinal plane TDI myocardial diastolic velocities at five sites on the mitral annulus included peak early myocardial tissue velocity (E'), peak late (or atrial) myocardial tissue velocity (A') and the ratio E'/A'. Standard pulsed-wave Doppler transmitral and pulmonary vein flow indices were also recorded along with measurements of body mass, heart rate, blood pressures and cardiac troponin T (cTnT), a biomarker of myocyte damage. Pre- to post-race changes in LV diastolic function were analysed by repeated measures ANOVA. Delta scores for LV diastolic function were correlated with each other and alterations in indices of LV loading. Diastolic longitudinal segmental and mean TDI data were altered post-race such that the mean E'/A' ratio was significantly depressed (1.51 +/- 0.34 to 1.16 +/- 0.35, P < 0.05). Changes in segmental and global TDI data were not related to an elevated post-race HR, a decreased post-race pre-load or an elevated cTnT. The pulsed wave Doppler ratio of peak early transmitral flow velocity (E)/peak late (or atrial) flow velocity (A) was also significantly reduced post-race (1.75 +/- 0.46 to 1.05 +/- 0.30, P < 0.05); however, it was significantly correlated with post-race changes in heart rate. The lack of change in E/E' from pre- to post-race (3.4 +/- 0.8 and 3.3 +/- 0.7, respectively) suggests that the depression in diastolic function is likely to be due to altered relaxation of the left ventricle; however, the exact aetiology of this change remains to be determined.

Pilot study of rapid infusion of 2 L of 4 degrees C normal saline for induction of mild hypothermia in hospitalized, comatose survivors of out-of-hospital cardiac arrest

BACKGROUND

Recent clinical studies have demonstrated that mild hypothermia (32 degrees C to 34 degrees C) induced by surface cooling improves neurological outcome after resuscitation from out-of-hospital cardiac arrest. Results from animal models suggest that the effectiveness of mild hypothermia could be improved if initiated as soon as possible after return of spontaneous circulation. Infusion of cold, intravenous fluid has been proposed as a safe, effective, and inexpensive technique to induce mild hypothermia after cardiac arrest.

METHODS AND RESULTS

In 17 hospitalized survivors of out-of-hospital cardiac arrest, we determined the effect on temperature and hemodynamics of infusing 2 L of 4 degrees C cold, normal saline during 20 to 30 minutes into a peripheral vein with a high-pressure bag. Data on vital signs, electrolytes, arterial blood gases, and coagulation were collected before and after fluid infusion. Cardiac function was assessed by transthoracic echocardiography before fluid administration and 1 hour after infusion. Passive (fans, leaving patient uncovered) or active (cooling blankets, neuromuscular blockade) cooling measures were used to maintain mild hypothermia for 24 hours. Infusion of 2 L of 4 degrees C cold, normal saline resulted in a mean temperature drop of 1.4 degrees C 30 minutes after the initiation of infusion. Rapid infusion of fluid was not associated with clinically important changes in vital signs, electrolytes, arterial blood gases, or coagulation parameters. The initial mean ejection fraction was 34%, and fluid infusion did not affect ejection fraction or increase central venous pressure, pulmonary pressures, or left atrial filling pressures as assessed by echocardiography. Passive measures were ineffective in maintaining hypothermia compared with active measures.

CONCLUSIONS

Infusion of 2 L of 4 degrees C cold, normal saline is safe and effective in rapidly lowering body temperature in survivors of out-of-hospital cardiac arrest.

Effect of age on left ventricular systolic function in humans: a study of systolic isovolumic acceleration rate

The aim of this study was to examine the effect of age on left ventricular (LV) systolic function in normal healthy adults. Eighty consecutive subjects without cardiovascular disease underwent standard and tissue Doppler (TD) echocardiographic imaging. LV systolic function was assessed by load-dependent indices as ejection fraction (EF) and myocardial systolic velocities by TD as well as by the load-independent index, systolic isovolumic acceleration rate (IVA). None of the echocardiographic measurements of systolic function declined with age (mean IVA for the group, 286 +/- 123 cm s(-2); IVA vs. age, r = 0.21, P = 0.1). Likewise, LV end diastolic dimension, wall thickness, mass and left atrial maximum volume were not significantly related to age. On the other hand, as previously reported, echocardiographic indices of diastolic function showed a significant decline with age (P < 0.05). When the group was stratified by gender, isovolumic velocity and acceleration were higher in men than women, but the differences were not significant (P = 0.12 and 0.37, respectively). No significant relation was observed between age and measurements of LV systolic function by regression analysis in women (P > 0.1). However, in men, a positive correlation was noted between average IVA and age (r = 0.63, P = 0.007). In conclusion, age is not associated with a change in cardiac structure and LV systolic function, but is accompanied by a decline in echocardiographic indices of diastolic function. With respect to gender, age does not appear to influence LV systolic function in women, but is associated with an increase in IVA and septal systolic ejection in men.