Right ventricular ejection fraction measurements using two-dimensional transthoracic echocardiography by applying an ellipsoid model.

BACKGROUND: There is today no established approach to estimate right ventricular ejection fraction (RVEF) using 2D transthoracic echocardiography (TTE). The aim of this study was to evaluate a new method for RVEF calculations using 2D TTE and compare the results with cardiac magnetic resonance (CMR) imaging and tricuspid annular plane systolic excursion (TAPSE). METHODS: A total of 37 subjects, 25 retrospectively included patients and twelve healthy volunteers, were included to give a wide range of RVEF. The right ventricle (RV) was modeled as a part of an ellipsoid enabling calculation of the RV volume by combining three distance measurements. RVEF calculated according to the model, RVEFTTE, were compared with reference CMR-derived RVEF, RVEFCMR. Further, TAPSE was measured in the TTE images and the correlations were calculated between RVEFTTE, TAPSE and RVEFCMR. RESULTS: The mean values were RVEFCMR = 43 ± 12% (range 20-66%) and RVEFTTE = 50 ± 9% (range 34-65%). There was a high correlation (r = 0.80, p < 0.001) between RVEFTTE and RVEFCMR. Bland-Altman analysis showed a mean difference between RVEFCMR and RVEFTTE of 6 percentage points (ppt) with limits of agreement from -11 to 23 ppt. The mean value for TAPSE was 19 ± 5 mm and the correlation between TAPSE and RVEFCMR was moderate (r = 0.54, p < 0.001). The correlation between RVEFTTE and RVEFCMR was significantly higher (p < 0.05) than the correlation between TAPSE and RVEFCMR. CONCLUSIONS: The ellipsoid model shows promise for RVEF calculations using 2D TTE for a wide range of RVEF, providing RVEF estimates that were significantly better correlated to RVEF obtained from CMR compared to TAPSE.

Determination of Right Ventricular Volume by Combining Echocardiographic Distance Measurements.

BACKGROUND: The position of the right ventricle (RV), often partly behind the sternum, implies difficulties to image the RV free wall using transthoracic echocardiography (TTE) and consequently limits the possibilities of stroke volume calculations. The aim of this study was to evaluate whether the volume of the right ventricle (RV) can be determined by combining TTE distance measurements that do not need the RV free wall to be fully visualized. METHODS: The RV volume was approximated by an ellipsoid composed of three distances. Distance measurements, modeled RV stroke volumes (RVSV), and RV ejection fraction (RVEF) were compared to reference values obtained from cardiac magnetic resonance (CMR) imaging for 12 healthy volunteers. RESULTS: Inter-modality comparisons showed that distance measurements were significantly underestimated in TTE compared to CMR. The modeled RV volumes using TTE distance measurements were underestimated compared to reference CMR volumes. There was, however, for TTE an agreement between modeled RVSV and left ventricular stroke volumes determined by biplane Simpson's rule. Similar agreement was shown between modeled RVSV based on CMR distance measurements and the CMR reference. Regarding RVEF, further studies including patients with a wider range of RVEF are needed to evaluate the method. CONCLUSION: In conclusion, the ellipsoid model of the RV provides good estimates of RVSVs, but volumes based on distance measurements from different modalities cannot be used interchangeably.

Effect on left ventricular mass and geometry in patients with takotsubo cardiomyopathy.

OBJECTIVES: Takotsubo cardiomyopathy (TTC) is a condition of transient left ventricular (LV) dysfunction. The effects on LV mass (LVM) and geometry have not been studied enough in TTC. Retrospectively, we analyzed our TTC cohort both by transthoracic echocardiography (TTE) and magnetic resonance imaging (MRI), for comparative purposes. DESIGN: Thirteen women undergoing TTE and MRI, at onset and three months later, were included. LVM was estimated by MRI, and two TTE methods. Segmental wall thickness (SWT) was measured, while radial strain was assessed by TTE. Data analysis included Wilcoxon's test (between phases), Mann-Whitney U test and McNemar's test (between and within groups). Bland-Altman analyses were used for intertechnique coherence, while interactions regarding TTE were tested using Spearman's coefficient. RESULTS: LVM decreased during recovery (p < 0.05), by MRI and one of the TTE methods; truncated ellipsoid formula (TEF), which also showed relatively better coherence compared with MRI. SWT decreased in two of three sites, by both modalities, but with ambiguous coherence there between. The TEF data interacted partially with a demonstrated increase in radial strain. CONCLUSIONS: TTC associates with acute increase in LVM, which appears to be an apical effect, tending to follow the changes in concentric wall motion. MRI and TTE show adequate coherence; primarily for the TEF method regarding LVM.

Multidisciplinary assessment of tako tsubo cardiomyopathy: a prospective case study.

BACKGROUND: The cause of tako tsubo cardiomyopathy remains unclear. We used a multidisciplinary approach to investigate if a common pathophysiological denominator could be outlined. METHODS: Within 3 days following symptom presentation and again after 3 months we investigated all patients coming to our institution and diagnosed with tako-tsubo cardiomyopathy. Patients underwent extensive biochemical screening. Left ventricular function was evaluated by echocardiography and contrast-enhanced cardiac magnetic resonance imaging. Cardiac autonomic function was studied by heart rate variability and signal-averaged electrocardiogram and posttraumatic stress and depression were investigated by questionnaires (the Posttraumatic Stress Syndrome 10-Questions Inventory, PTSS-10 and the Montgomery-Åsberg depression rating scale, self rated version, MADRS-S). RESULTS: During 2 years, 13 consecutive patients were included. Markers of myocardial damage and heart failure were slightly to moderately elevated and ejection fraction (echocardiography and MRi) was moderately reduced at hospitalization and improved to normal values in all patients. Signal averaged ECG demonstrated a statistically significant shorter duration of the filtered QRS complex in the acute phase as compared to follow-up. In heart rate variability analysis, SDNN and SDANN were shorter acutely compared to follow-up. Two patients fulfilled criteria for posttraumatic stress syndrome while 7 patients were in the borderline zone. There was a statistically significant inverse correlation between PTSS-10 score and QRS duration in the signal-averaged ECG (r = -0.66, P = 0.01). CONCLUSIONS: Patients with tako tsubo cardiomyopathy have altered cardiac autonomic function and a high incidence rate of borderline or definite posttraumatic stress syndrome acutely. This is in line with findings in patients with myocardial infarction and does not allow conclusions on cause and effect.

Freeze-dried bilberry (Vaccinium myrtillus) dietary supplement improves walking distance and lipids after myocardial infarction: an open-label randomized clinical trial.

Bilberries, Vaccinium myrtillus, have a high content of phenolic compounds including anthocyanins, which could provide cardiometabolic health benefits following acute myocardial infarction (AMI). We hypothesized that standard medical therapy supplemented with freeze-dried bilberry after AMI would have a more beneficial effect on cardiovascular risk markers and exercise capacity than medical therapy alone. Patients were allocated in a 1:1 ratio within 24 hours of percutaneous coronary intervention in an 8-week trial either to V myrtillus powder (40 g/d, equivalent to 480 g fresh bilberries) and standard medical therapy or to a control group receiving standard medical therapy alone. High-sensitivity C-reactive protein and exercise capacity measured with the 6-minute walk test were the primary biochemical and clinical end points, respectively. Fifty subjects completed the study. No statistically significant difference in high-sensitivity C-reactive protein was detected between groups. The mean 6-minute walk test distance increased significantly more in the bilberry group compared to the control group: mean difference 38 m at follow-up (95% confidence interval 14-62, P = .003). Ex vivo oxidized low-density lipoprotein was significantly lowered in the bilberry group compared to control, geometric mean ratio 0.80 (95% confidence interval 0.66-0.96, P = .017), whereas total cholesterol and low-density lipoprotein cholesterol did not differ significantly between groups. Anthocyanin-derived metabolites in blood increased significantly in the bilberry group during the intervention and were different after 8 weeks between the bilberry group and control. Findings in the present study suggest that bilberries may have clinically relevant beneficial effects following AMI; a larger, double-blind clinical trial is warranted to confirm this.

Diastolic function improves after resolution of takotsubo cardiomyopathy.

BACKGROUND: Takotsubo cardiomyopathy (TTC) is a condition of reversible left ventricular (LV) systolic dysfunction. However, the diastolic function (DF) manifestations of TTC have not been widely investigated. We performed a bicentric study with retrospective analysis of DF in patients with TTC, during onset and at follow-up. METHODS: Twenty-eight patients with TTC (64 ± 10 years, F 24) were included. All underwent echocardiograms acutely and at the recovery phase (average three months later). Diastolic and systolic function parameters were recorded, including E-wave velocity (E), A-wave velocity, E/A ratio, relaxation (e') and contractility (S') based on tissue Doppler velocities of the mitral annuli, ejection fraction (EF), left atrial (LA) size and DF stages. RESULTS: Recovery, including the mean difference with 95% confidence interval, was associated with tending improvement (i.e. uncorrected significance) in E [13 cm s(-1) (-24, -2·3), P = 0·02] and in E/A ratio [0·2 (-0·41, -0·02), P = 0·04], as well as significant improvement (after multiple comparison correction) in mean e' [2·0 cm s(-1) (-3·3, -1·2), P<0·001] and in A-wave duration [29 ms (-46·7, -12·7), P = 0·002]. LA area tended to decrease during recovery [-2 cm² (0·33, 2·4), P = 0·01]. Improvement in DF stages was significant between the phases (21% versus 58% defined as normal DF, P = 0·016). Improvement in LVEF correlated with improvement in mean e' (r = 0·52, P = 0·02). CONCLUSIONS: TTC is associated with an acute impairment of conventional DF variables, which improves during recovery. DF recovery seems to occur in parallel with systolic recovery in patients with TTC.