Reliability of echocardiographic speckle-tracking derived bi-atrial strain assessment under different hemodynamic conditions

Early SGLT2 inhibitor use is associated with improved left atrial strain following acute coronary syndrome

AIM

Left atrial (LA) strain, a novel marker of LA function, reliably predicts diastolic dysfunction. SGLT2 inhibitors improve heart failure outcomes, but limited data exists regarding their use in the immediate aftermath of acute coronary syndrome (ACS). We studied the effect of empagliflozin on LA strain in patients with type 2 diabetes (T2D) and ACS.

METHODS

Patients with ACS and T2D were identified and empagliflozin was initiated in eligible patients prior to discharge. Patients not initiated on empagliflozin were analysed as a comparator group. A blinded investigator assessed LA strain using baseline and 3-6 month follow-up echocardiograms.

RESULTS

Forty-four participants (n = 22 each group) were included. Baseline characteristics and LA strain were similar in the two groups. LA reservoir, conduit and contractile strain increased in empagliflozin group (28.0 ± 8.4% to 34.6 ± 12.2% p < 0.001, 14.5 ± 5.4% to 16.7 ± 7.0% p = 0.034, 13.5 ± 5.2% to 17.9 ± 7.2% p = 0.005, respectively) but remained unchanged in comparison group (29.2 ± 6.7% to 28.8 ± 7.0%, 12.8 ± 4.2% to 13.3 ± 4.7%, 16.7 ± 5.3% to 15.5 ± 4.5%, respectively, p = NS). The difference in change between groups was significant for LA reservoir (p = 0.003) and contractile strain (p = 0.005).

CONCLUSION

In patients with ACS and T2D, addition of empagliflozin to standard ACS therapy prior to discharge is associated with improved LA function.

Cardiac remodeling after atrial septal defects device closure

BACKGROUND

Trans-catheter device closure of secundum type atrial septal defects (ASDs) has now become the treatment of choice. Device closure affects the hemodynamics and function of the heart. In the current study, we investigated the remodeling of the heart as assessed by advanced echocardiographic parameters following successful device closure.

METHODS

A prospective cohort study was conducted and 45 patients who were eligible for ASD device closure were evaluated for volumetric, functional, Doppler, strain, and strain rate data of left and right atrium and ventricle pre-procedural and 48 h post-procedure RESULTS: In a prospective cohort study 45 patients who were eligible for ASD device closure; atrial and ventricular volumetric, functional, Doppler, strain, and strain rate data were recorded and compared pre-procedurally and 48 h post-procedure.We found significant changes in the left ventricular (LV) end diastolic volume index (p-value = .03), right ventricular (RV) diameter (p-value = <.001), left atrial (LA) volume index (p-value = .05), right atrial (RA) volume index (p-value = .001), and right and left sided E/e' ratio with a p-value of .001 and .004, respectively. Our findings showed a significant reduction in the strains of the right and left atria and the right ventricular free wall after ASD device closure. LV global longitudinal strain decreased after the procedure but did not reach statistical significance.

CONCLUSION

ASD patients have impaired global strains compared to normal defined ranges. LA, RA, and RV strains show significant reduction after device closure. Decline in LA function following closure was greater in those with larger ASDs. In adult patients undergoing the procedure, abnormal LA function is a clinically relevant issue demanding pre and post- procedural precautions and treatment.

Effects of acetazolamide on pulmonary artery pressure and prevention of high altitude pulmonary edema after rapid active ascent to 4,559 m

Acetazolamide prevents acute mountain sickness (AMS) by inhibition of carbonic anhydrase. Since it reduces acute hypoxic pulmonary vasoconstriction (HPV), it may also prevent high-altitude pulmonary edema (HAPE) by lowering pulmonary artery pressure. We tested this hypothesis in a randomized, placebo-controlled, double-blind study. Thirteen healthy, non-acclimatized lowlanders with a history of HAPE ascended (<22h) from 1,130 to 4,559m with one overnight stay at 3,611m. Medications started 48h before ascent (acetazolamide: n=7, 250mg 3x/d; placebo: n=6, 3x/d). HAPE was diagnosed by chest radiography, and pulmonary artery pressure by measurement of right ventricular to atrial pressure gradient (RVPG) by transthoracic echocardiography. AMS was evaluated with the Lake Louise Score (LLS) and AMS-C Score. Incidence of HAPE was 43% vs. 67% (acetazolamide vs. placebo, p=0.39). Ascent to altitude increased RVPG from 20±5 to 43±10mmHg (p<0.001) without a group difference (p=0.68). Arterial PO₂ fell to 36±9mmHg (p<0.001) and was 8.5mmHg higher with acetazolamide at high altitude (p=0.025). At high altitude, the LLS and AMS-C score remained lower in those taking acetazolamide (both p<0.05). Although acetazolamide reduced HAPE incidence by 35%, this effect was not statistically significant, and considerably less than reductions of about 70-100% with prophylactic dexamethasone, tadalafil, and nifedipine performed with the same ascent profile at the same location. We could not demonstrate a reduction in RVPG compared to placebo treatment despite reductions in AMS severity and better arterial oxygenation. Limited by a small sample size, our data do not support recommending acetazolamide for prevention of HAPE in mountaineers ascending rapidly to over 4,500m.

Evaluation of the right atrial phasic functions in patients with anterior ST-elevation myocardial infarction: a 2D speckle-tracking echocardiography study

Background

Evidence suggests that changes in left ventricular systolic and diastolic functions may affect right atrial (RA) phasic functions. We aimed to evaluate RA phasic functions in the presence of anterior ST-elevation myocardial infarction (ASTEMI) as an acute event and to compare the findings with those in a control group.

Methods

We recruited 92 consecutive ASTEMI patients without accompanying significant stenosis in the proximal and middle parts of the right coronary artery and 31 control subjects, matched for age, sex, diabetes, and hypertension. RA phasic functions were evaluated concerning their longitudinal 2D speckle-tracking echocardiography-derived markers. The ASTEMI group was followed up for all-cause mortality or reinfarction.

Results

In the ASTEMI group, RA strain was reduced during the reservoir (33.2% ± 4.3% vs 30.5% ± 8.1%; P = 0.021) and conduit (16% [12–18%] vs 14% [9–17%]; P = 0.048) phases. The other longitudinal 2D speckle-tracking echocardiography-derived markers of RA phasic functions were not different between the 2 groups. RA strain and strain rate during the contraction phase were predictive of all-cause mortality or reinfarction (hazard ratio = 0.80; P = 0.024 and hazard ratio = 0.39; P = 0.026, respectively).

Conclusions

Based on 2D speckle-tracking echocardiography, in the ASTEMI group, compared with the control group, RA reservoir and conduit functions were reduced, while RA contraction function was preserved. RA contraction function was predictive of all-cause mortality or reinfarction during the follow-up period.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-022-02546-4.

Preserved right ventricular function but increased right atrial contractile demand in altitude-induced pulmonary hypertension

Purpose

Ascent to high altitude increases right ventricular (RV) afterload and decreases myocardial energy supply. This study evaluates physiologic variables and comprehensive echocardiographic indices of RV and right atrial (RA) function following rapid ascent to high altitude.

Methods

Fifty healthy volunteers actively ascended from 1130 to 4559 m in < 22 h. All participants underwent 2D echocardiography during baseline examination at low altitude (424 m) and at three study time-points (7, 20 and 44 h) after arrival at high altitude. In addition to systolic pulmonary artery pressure (sPAP), comprehensive 2D planimetric-, tissue Doppler- and speckle-tracking-derived strain indices of RA and RV function were obtained.

Results

sPAP increased from baseline (24 ± 4 mmHg) to the first altitude examination (39 ± 8 mmHg, p < 0.001) and remained elevated during the following 44 h. Global RV function did not change. RA reservoir strain showed a trend towards increase from baseline (50.2 ± 12.1%) to the first altitude examination (53.8 ± 11.0%, p = 0.07) secondary to a significant increase of RA contraction strain (19.2 ± 6.4 vs. 25.4 ± 9.6%, p < 0.001). Volumetric RA data largely paralleled RA strain results and RA active emptying volume was increased throughout the 44 h stay at high altitude.

Conclusion

Active and rapid ascent of healthy individuals to 4559 m is associated with an increased contractile performance of the RA that compensates for the increased workload of the RV.

Electronic supplementary material

The online version of this article (10.1007/s10554-020-01803-x) contains supplementary material, which is available to authorized users.

Impairment of left atrial mechanics does not contribute to the reduction in stroke volume after active ascent to 4559 m

Hypoxia challenges left ventricular (LV) function due to reduced energy supply. Conflicting results exist whether high‐altitude exposure impairs LV diastolic function and thus contributes to the high altitude‐induced increase in systolic pulmonary artery pressure (sPAP) and reduction in stroke volume (SV). This study aimed to assess LV diastolic function, LV end‐diastolic pressure (LVEDP), and LA mechanics using comprehensive echocardiographic imaging in healthy volunteers at 4559 m. Fifty subjects performed rapid (<20 hours) and active ascent from 1130 m to 4559 m (high). All participants underwent echocardiography during baseline examination at 424 m (low) as well as 7, 20 and 44 hours after arrival at high altitude. Heart rate (HR), sPAP, and comprehensive volumetric‐ and Doppler‐ as well as speckle tracking‐derived LA strain parameters were obtained to assess LV diastolic function, LA mechanics, and LVEDP in a multiparametric approach. Data for final analyses were available in 46 subjects. HR (low: 64 ± 11 vs high: 79 ± 14 beats/min, P < 0.001) and sPAP (low: 24.4 ± 3.8 vs high: 38.5 ± 8.2 mm Hg, P < 0.001) increased following ascent and remained elevated at high altitude. Stroke volume (low: 64.5 ± 15.0 vs high: 58.1 ± 16.4 mL, P < 0.001) and EDV decreased following ascent and remained decreased at high altitude due to decreased LV passive filling volume, whereas LA mechanics were preserved. There was no case of LV diastolic dysfunction or increased LVEDP estimates. In summary, this study shows that rapid and active ascent of healthy individuals to 4559 m impairs passive filling and SV of the LV. These alterations were not related to changes in LV and LA mechanics.

Speckle tracking-derived bi-atrial strain before and after eleven weeks of training in elite rowers

The left (LA) and right (RA) atria undergo adaptive remodeling in response to hemodynamic stress not only induced by endurance exercise but also as part of several cardiovascular diseases thereby confounding differential diagnosis. Echocardiographic assessment of the atria with novel speckle tracking (STE)-derived variables broadens the diagnostic spectrum compared to conventional analyses and has the potential to differentiate physiologic from pathologic changes. The purpose of this study was to assess and categorize baseline values of bi-atrial structure and function in elite rowers according to recommended cutoffs, and to assess the cardiac changes occurring with endurance training. Therefore, fifteen elite rowers underwent 2D-echocardiographic analysis of established variables of cardiac structure and function as well as STE-derived variables of bi-atrial function. Measurements were performed at baseline and after eleven weeks of extensive training. 40% of athletes displayed mildly enlarged LA and 47% mildly enlarged RA at baseline, whereas no athlete fell below the lower reference values of LA and RA reservoir strain. Average power during a 2000 m ergometer rowing test (P2000 m) improved from 426 ± 39 W to 442 ± 34 W (p = 0.010) but there were no changes of echocardiographic variables following training. In elite rowers, longitudinal bi-atrial strain assessment indicates normal resting function of structurally enlarged atria and thereby may assist to differentiate between exercise-induced versus disease-associated structural cardiac changes in which function is commonly impaired.

Reproducibility of global left atrial strain and strain rate between novice and expert using multi-vendor analysis software

Left atrial (LA) strain is an emerging technique with potential applications including arrhythmia prediction in atrial fibrillation and early identification of atrial dysfunction. The aim of this study was to evaluate reproducibility of LA strain and strain rate (SR) using multi-vendor analysis software between novice and expert. For LA strain to be a reliable tool, the technique must be reproducible by observers with variable experience. Use of multi-vendor analysis software allows serial strain assessment when echocardiographic images are acquired using different vendors. Fifty subjects underwent 2D-Speckle tracking echocardiographic (STE) derived LA strain and SR analysis measured from apical four and two-chamber views. Three strain parameters of LA function were assessed: reservoir (S-LAs, SR-LAs), contractile (S-LAa, SR-LAa) and conduit (S-LAs-S-LAa, SR-LAe). Strain analyses were performed by 2 independent, blinded novice and expert observers using multi-vendor analysis software. Intraobserver and interobserver analyses were performed using intra class correlation coefficients (ICC) and Bland-Altman analysis. LA strain and SR measured by novice observer demonstrated excellent intraobserver reproducibility (ICC for all strain and SR values > 0.88). There was good interobserver agreement of LA strain values between novice and expert (S-LAs:ICC 0.81, S-LAe:ICC 0.82, S-LAa:ICC 0.74). SR values also demonstrated good interobserver agreement (SR-LAs:ICC 0.83, SR-LAe:ICC 0.79, SR-LAa:ICC 0.86). Of all parameters, SR-LAa had the best interobserver and intraobserver agreement (ICC 0.86, 0.96). Global LA strain and SR values were highly reproducible by novice strain reader using multi-vendor analysis software. Interobserver reproducibility between novice and experts were good and acceptable within limits of agreement.