Atrioventricular nodal reentry tachycardia in pregnancy: 'I have ice for you'

Background

Pregnancy is a known trigger of novel and pre-existing supraventricular tachyarrhythmias. We present a case of a stable pregnant patient presenting with atrioventricular nodal reentry tachycardia (AVNRT) and application of the 'facial ice immersion technique'.

Case summary

A 37-year-old pregnant woman presented with recurrent AVNRT. Due to unsuccessful attempts of conventional vagal manoeuvres (VMs) and refusal of pharmacological agents, we successfully performed a non-conventional VM with the 'facial ice immersion technique'. This technique was applied successfully at repeated clinical presentation.

Discussion

The role of non-pharmacological interventions remains pivotal and may lead to desired therapeutical effects without the use of any costly pharmacological agents with possible adverse events. However, non-conventional VMs such as the 'facial ice immersion technique' are less commonly known but appear to be easy and a safe option for both mother and foetus in the management of AVNRT during pregnancy. Clinical awareness and understanding of treatment options are imperative in contemporary patient care.

Chronic Obstructive Pulmonary Disease and Risk of Atrial Arrhythmias After ST-Segment Elevation Myocardial Infarction

Background

ST-segment elevation myocardial infarction (STEMI) and cardiac arrhythmias frequently occur in patients with chronic obstructive pulmonary disease (COPD). However, little is known about the association of COPD with the occurrence of atrial arrhythmias after STEMI.

Methods

This retrospective analysis consisted of 320 patients with first STEMI without a history of atrial arrhythmias, with available 24-hour holter-ECG at 3- and/or 6 months follow-up. In total, 80 COPD patients were compared with 240 non-COPD patients, matched by age and gender (mean age 67±10 years, 74% male). Atrial arrhythmias were defined as: atrial fibrillation/flutter, atrial tachycardia (≥3 consecutive premature atrial contractions (PAC's)) and excessive supraventricular ectopy activity (ESVEA, ≥30 PAC's/hour or runs of ≥20 PAC's).

Results

Baseline characteristics were similar among COPD and non-COPD patients regarding infarct location, β-blocker use and cardiovascular risk profile except for smoking (69% vs. 49%, respectively, p=0.002). Additionally, atrial volumes, LVEF and TAPSE were comparable. During 1 year follow-up, a significantly higher prevalence of atrial tachycardia and ESVEA was observed in patients with COPD as compared to non-COPD patients (70% vs. 46%; p<0.001 and 21% vs. 11%; p=0.024, respectively). In multivariate analysis, COPD was independently associated with the occurrence of atrial arrhythmias (combined) during 1 year of follow-up (HR 3.59, 95% CI 1.78-7.22; p<0.001).

Conclusion

COPD patients after STEMI have a significantly higher prevalence of atrial tachycardia and ESVEA within 1 year follow-up as compared to age- and gender matched patients without COPD. Moreover, COPD is independently associated with an increased prevalence of atrial arrhythmias after STEMI.

Prevalence of Aortic Valve Stenosis in Patients With ST-Segment Elevation Myocardial Infarction and Effect on Long-Term Outcome

Several studies have shown an association between aortic valve stenosis (AS), atherosclerosis and cardiovascular risk factors. These risk factors are frequently encountered in patients with ST-segment elevation myocardial infarction (STEMI). The aim of this study was to evaluate the prevalence and the prognostic implications of AS in patients presenting with STEMI. A total of 2041 patients (61 ± 12 years old, 76% male) admitted with STEMI and treated with primary percutaneous coronary intervention were included. Patients with previous myocardial infarction and previous aortic valve replacement were excluded. Echocardiography was performed at index admission. Patients were divided in 3 groups: 1) any grade of AS, 2) aortic valve sclerosis and 3) normal aortic valve. Any grade of AS was defined as an aortic valve area ≤2.0 cm². The primary endpoint was all-cause mortality. The prevalence of AS was 2.7% in the total population and it increased with age (1%, 3%, 7% and 16%, in the patients aged <65 years, 65 to 74 years, 75 to 84 years and ≥85 years, respectively). Patients with AS showed a significantly higher mortality rate when compared to the other two groups (p < 0.001) and AS was independently associated with all-cause mortality, with a HR of 1.81 (CI 95%: 1.02 to 3.22; p = 0.04). In conclusion, AS is not uncommon in patients with STEMI, and concomitant AS in patients with first STEMI is independently associated with all-cause mortality at long-term follow up.

Right ventricular myocardial work: proof-of-concept for non-invasive assessment of right ventricular function

AIMS

Right ventricular myocardial work (RVMW) is a novel method for non-invasive assessment of right ventricular (RV) function utilizing RV pressure-strain loops. This study aimed to explore the relationship between RVMW and invasive indices of right heart catheterization (RHC) in a cohort of patients with heart failure with reduced left ventricular ejection fraction (HFrEF), and to compare values of RVMW with those of a group of patients without cardiovascular disease.

METHODS AND RESULTS

Non-invasive analysis of RVMW was performed in 22 HFrEF patients [median age 63 (59-67) years] who underwent echocardiography and invasive RHC within 48 h. Conventional RV functional measurements, RV global constructive work (RVGCW), RV global work index (RVGWI), RV global wasted work (RVGWW), and RV global work efficiency (RVGWE) were analysed and compared with invasively measured stroke volume and stroke volume index. Non-invasive analysis of RVMW was also performed in 22 patients without cardiovascular disease to allow for comparison between groups. None of the conventional echocardiographic parameters of RV systolic function were significantly correlated with stroke volume or stroke volume index. In contrast, one of the novel indices derived non-invasively by pressure-strain loops, RVGCW, demonstrated a moderate correlation with invasively measured stroke volume and stroke volume index (r = 0.63, P = 0.002 and r = 0.59, P = 0.004, respectively). RVGWI, RVGCW, and RVGWE were significantly lower in patients with HFrEF compared to a healthy cohort, while values of RVGWW were significantly higher.

CONCLUSION

RVGCW is a novel parameter that provides an integrative analysis of RV systolic function and correlates more closely with invasively measured stroke volume and stroke volume index than other standard echocardiographic parameters.

Prognostic Value of Multilayer Left Ventricular Global Longitudinal Strain in Patients with ST-segment Elevation Myocardial Infarction with Mildly Reduced Left Ventricular Ejection Fractions

Multilayer (epi-, mid- and endocardium) left ventricular (LV) global longitudinal strain (GLS) reflects the extent of myocardial damage after ST-segment myocardial infarction (STEMI). However, the prognostic implications of multilayer LV GLS remain unclear. We studied the association between multilayer LV GLS and prognosis in patients with mildly reduced or preserved LV ejection fraction (EF) after STEMI. Patients with first STEMI and LVEF>45% were evaluated retrospectively. Baseline multilayer (endocardial, mid-myocardial and epicardial) LV GLS were measured on 2-dimensional speckle tracking echocardiography. Patients were followed up for of all-cause mortality. A total of 569 patients (77% male, 60 ± 11 years) were included. After a median follow-up of 117 (interquartile range 106-132) months, 95 (17%) patients died. We observed no differences in baseline LVEF and peak troponin levels between survivors and non-survivors. However, non-survivors showed more impaired GLS at all layers (epicardium: -11.9 ± 2.8% vs. -13.4 ± 2.8%; mid-myocardium: -14.2 ± 3.2% vs. -15.6 ± 3.2%; endocardium: -16.5 ± 3.7% vs. -17.7 ± 3.6%, p <0.05, for all). On multivariable analysis, increasing age (hazard ratio 1.095; p<0.001) and impaired LV GLS of the epicardial layer (hazard ratio 1.085; p = 0.047) were independently associated with higher risk of all-cause mortality. In addition, LV GLS at the epicardium had incremental prognostic value for all-cause mortality (χ² = 114, p = 0.044). In conclusion, in contemporary STEMI patients with mildly reduced or preserved LVEF, ageing and reduced LV GLS of the epicardium (reflecting transmural scar formation) were independently associated with all-cause mortality after adjusting for clinical and echocardiographic variables.

Left ventricular mechanical dispersion in ischaemic cardiomyopathy: association with myocardial scar burden and prognostic implications

AIMS

Left ventricular (LV) mechanical dispersion (MD) may result from heterogeneous electrical conduction and is associated with adverse events. The present study investigated (i) the association between LV MD and the extent of LV scar as assessed with contrast-enhanced cardiac magnetic resonance (CMR) and (ii) the prognostic implications of LV MD in patients after ST-segment elevation myocardial infarction.

METHODS AND RESULTS

LV MD was calculated by echocardiography and myocardial scar was analysed on CMR data retrospectively. Infarct core and border zone were defined as ≥50% and 35-50% of maximal signal intensity, respectively. Patients were followed for the occurrence of the combined endpoint (all-cause mortality and appropriate implantable cardioverter-defibrillator therapy). In total, 96 patients (87% male, 57 ± 10 years) were included. Median LV MD was 53.5 ms [interquartile range (IQR) 43.4-62.8]. On CMR, total scar burden was 11.4% (IQR 3.8-17.1%), infarct core tissue 6.2% (IQR 2.0-12.7%), and border zone was 3.5% (IQR 1.5-5.7%). Correlations were observed between LV MD and infarct core (r = 0.517, P < 0.001), total scar burden (r = 0.497, P < 0.001), and border zone (r = 0.298, P = 0.003). In total, 14 patients (15%) reached the combined endpoint. Patients with LV MD >53.5 ms showed higher event rates as compared to their counterparts. Finally, LV MD showed the highest area under the curve for the prediction of the combined endpoint.

CONCLUSION

LV MD is correlated with LV scar burden. In addition, patients with prolonged LV MD showed higher event rates. Finally, LV MD provided the highest predictive value for the combined endpoint when compared with other parameters.

Prognostic implications of left ventricular myocardial work index in patients with ST-segment elevation myocardial infarction and reduced left ventricular ejection fraction

AIMS

This study aimed to determine whether lower values of left ventricular (LV) global work index (GWI) at baseline were associated with a reduction in LV functional recovery and poorer long-term prognosis in patients with reduced LV ejection fraction (LVEF ≤40%) following ST-segment elevation myocardial infarction (STEMI).

METHODS AND RESULTS

A total of 197 individuals (62 ± 12 years, 75% male) with STEMI treated with primary percutaneous coronary intervention and reduced LVEF were evaluated. All patients were followed up for the occurrence of all-cause mortality and the presence of LVEF normalization at 6 months (LVEF ≥50%). The median LVEF was 36% (interquartile range 32-38) and the mean value of LV GWI was 1041 ± 404 mmHg% at baseline. At 6-month follow-up, 41% of patients had normalized LVEF. On multivariable logistic regression, higher values of LV GWI were independently associated with LVEF normalization at 6 months of follow-up (odds ratio 1.32 per 250 mmHg%, P = 0.038). Over a median follow-up of 112 months, 40 patients (20%) died. LV GWI <750 mmHg% was independently associated with all-cause mortality (HR 3.85, P < 0.001) and was incremental to LV global longitudinal strain (P = 0.039) and LVEF (P < 0.001).

CONCLUSION

In individuals with an LVEF ≤40% following STEMI, higher values of LV GWI were associated with a greater probability of LVEF normalization at 6-month follow-up. In addition, lower values of LV GWI were independently associated with increased all-cause mortality at long-term follow-up, providing incremental prognostic value over LVEF and minor incremental prognostic value over LV global longitudinal strain.

Non-invasive myocardial work: an echocardiographic measure of post-infarct scar on contrast-enhanced cardiac magnetic resonance imaging

Background

Late gadolinium contrast enhanced cardiac magnetic resonance (LGE CMR) imaging accurately quantifies the extent of fibrosis and transmurality in chronically infarcted left ventricular (LV) segments, and identifies viability. Moreover, CMR characterizes the remote, non-infarcted zone, which is an emerging region of interest following ST-segment elevation myocardial infarction (STEMI). Non-invasive myocardial work is a novel LV function parameter - calculated from speckle-tracking strain echocardiography and sphygmomanometrically-determined blood pressure, which has shown excellent correlation with invasively measured myocardial work.

Purpose

To explore the relation of non-invasively estimated parameters of LV myocardial work to post-infarct scar on LGE CMR, and to compare myocardial work indices between the infarct core and remote zone in STEMI patients who were treated with primary percutaneous coronary intervention (PCI).

Methods

Patients with a STEMI who underwent primary PCI and LGE CMR, in addition to echocardiographic studies where non-invasive myocardial work analysis was feasible, were included. The LV was subdivided into non-infarcted, non-transmural and transmurally infarcted segments. The remote zone was defined as the non-infarcted myocardial segment diametrically opposed to the infarct core, without any evidence of LGE. Myocardial work indices were compared with linear mixed models, ANOVA and Wilcoxon signed rank tests.

Results

53 patients (89% male, age 58±9 years) and 689 segments were analysed. The mean scar burden comprised 14±7% of the total LV mass and 76 (11%) segments showed transmural LGE. The following non-invasive myocardial work indices: myocardial work index (MWI), constructive work (CW) and myocardial work efficiency (MWE) showed a significant inverse relationship with infarct transmurality (p&lt;0.05 for all comparisons) while a positive trend was observed for wasted work (WW) (p=0.086) (Figure 1). The core zone demonstrated lesser MWI (1237±568 vs. 1514±518 mmHg%; p=0.010), CW (1331±627 vs. 1827±537 mmHg%; p&lt;0.001) and MWE (92 (84–98) vs. 98 (95–99) %; p&lt;0.001) as well as greater WW when compared to the remote zone (107 (26–196) vs. 26 (10–90) mmHg%; p=0.001).

Conclusions

In STEMI patients who underwent primary PCI, MWI, CW and MWE were significantly related to the extent of transmural infarction, while WW demonstrated a trend. MWI, CW and MWE were significantly lower, and WW higher, in the core zone compared to the remote zone. Non-invasive myocardial work indices may provide an echocardiographic method for determining post-infarct viability, as well as characterization of the remote zone.

MW and scar transmurality on LGE CMR

Funding Acknowledgement

Type of funding source: None

Progressive left ventricular post-infarction remodelling: impact on outcome

Background

While the presence left ventricular (LV) remodelling after ST-segment elevation myocardial infarction (STEMI) is known to worsen prognosis, the impact of progressive vs. stable LV remodelling on outcome has not been established.

Purpose

To investigate the impact of progressive LV remodelling on outcome in STEMI patients who were treated with primary percutaneous coronary intervention (PCI) and optimal pharmacotherapy.

Methods

Baseline, 3-, 6- and 12-month echocardiograms were analysed. Early LV remodelling (ER) was defined as a ≥20% increase in LV end-diastolic volume (EDV) during the first 3 months post-STEMI, and mid-term remodelling (MTR) as ≥20% LVEDV change by 6 months. Progressive LV remodelling was defined according to spline curve analyses: ≥0% LVEDV increase by 6 months (i.e. further increase after 3 months) for ER, and ≥20% by 12 months (i.e. an additional increase after 6 months) for MTR. The impact of progressive LV remodelling on outcome was evaluated with a Log rank test.

Results

589 STEMI patients (mean age 61±12 years, 78% male) who demonstrated LV remodelling in the first 6 months post-infarct, were analysed: 408 (69%) ER and 181 (31%) MTR. Progressive LV remodelling occurred in 146 (36%) ER and in 12 (7%) MTR. After a median follow-up of 90 (IQR 64–117) months, 39 (10%) ER were hospitalised for heart failure. 25 (14%) MTR remodellers died after a median follow-up of 86 (IQR 66–112) months. Progressive LV remodelling in ER led to a higher rate of heart failure hospitalisation (P=0.017 vs. non-progressive ER, Fig. 1A) but no mortality difference (P=0.10 vs. non-progressive ER). In contrast, MTR with progressive LV remodelling experienced worse survival (P=0.01 vs. non-progressive MTR, Fig. 1B) but no increase in heart failure hospitalisation (P=0.65 vs. non-progressive MTR).

Conclusions

Progressive LV remodelling causes an increased risk of heart failure in ER post-infarct, vs. higher mortality in MTR. These two patterns of progressive, post-infarct LV remodelling possibly represent different underlying pathophysiological mechanisms: i.e. evolution of true post-infarct remodelling in ER, vs. natural history of established heart failure in MTR.

Figure 1

Funding Acknowledgement

Type of funding source: None

Association Between Flow Impairment in Dominant Coronary Atrial Branches and Atrial Arrhythmias in Patients With ST-Segment Elevation Myocardial Infarction

OBJECTIVES

The impact of atrial ischemia in the occurrence of atrial arrhythmias may vary based on the amount of jeopardized myocardium. We sought to determine the association between coronary flow impairment in dominant coronary atrial branches (CAB) and atrial arrhythmias at 1-year follow-up in ST-segment elevation myocardial infarction (STEMI) patients.

METHODS

Patients with STEMI involving the right or circumflex coronary artery were included. Dominant CAB was defined as the most developed CAB. Patients were followed-up during 1 year, including 24-h Holter ECG at 3 and 6 months. Atrial arrhythmias were defined as atrial fibrillation/flutter, atrial tachycardia (≥3 consecutive supraventricular ectopic beats) and excessive supraventricular ectopic activity (>30 supraventricular beats/h or runs ≥20 beats).

RESULTS

A dominant CAB was identified in 897 of 900 patients STEMI (age 61 ± 12 years, 79% male). TIMI flow < 3 at the dominant CAB was present in 69 (8%) patients. Compared to those with dominant CAB preserved flow, patients with dominant CAB flow impairment presented with higher levels of troponin T (3.9 [2.2-8.2] vs. 3.1 [1.3-5.8], P = 0.008)and higher rates of atrial tachycardia at 3 months (68% vs. 37%, P = 0.007) and more supraventricular ectopic beats both at 3 months (58 [21-235] vs. 33 [12-119], P = 0.02) and at 6 months (62 [24-156] vs. 32 [12-115]; P = 0.04) on 24-h Holter ECG. Age and an impaired coronary flow at the dominant CAB were independently related to a higher risk of developing atrial arrhythmias at 1-year follow-up.

CONCLUSION

Dominant CAB flow impairment is infrequent and is associated with the occurrence of atrial arrhythmias, in the form atrial tachycardia and supraventricular ectopic beats, at follow-up.

Correlates and Long-Term Implications of Left Ventricular Mechanical Dispersion by Two-Dimensional Speckle-Tracking Echocardiography in Patients with ST-Segment Elevation Myocardial Infarction

BACKGROUND

Left ventricular (LV) mechanical dispersion (LVMD), measured with speckle-tracking echocardiography (STE) after ST-segment elevation myocardial infarction (STEMI), has been proposed as a measurement of regional heterogeneity of myocardial contraction and may reflect changes in the myocardial structure (e.g., fibrosis or edema). Further insight into this parameter may aid in the risk stratification of STEMI patients.

METHODS

A total of 1,000 STEMI patients (77% male, 60 ± 12 years) treated with primary percutaneous coronary intervention were retrospectively analyzed. The LVMD was assessed with two-dimensional STE within 48 hours following the index infarction. Patients were followed for the occurrence of all-cause mortality.

RESULTS

After a median follow-up of 117 months, 229 (23%) patients died. Nonsurvivors showed worse LV ejection fraction (43% ± 10% vs 48% ± 9%; P < .001) and global longitudinal strain (-12.0% ± 3.5% vs -14.2% ± 3.5%; P = .001) and prolonged LVMD (63 [interquartile range, 50-85] msec vs 52 [interquartile range, 42-63] msec; P < .001) compared with survivors. Increasing age, systolic blood pressure, and heart rate at discharge as well as diabetes mellitus, anterior STEMI, TIMI flow < 2, less usage of angiotensin converter enzyme inhibitors or angiotensin receptor blockers, and impaired LV global longitudinal strain were independently associated with more prolonged LVMD. On multivariable analysis, prolonged LVMD was independently associated with increased risk of all-cause mortality (hazard ratio = 1.012; 95% CI, 1.005-1.018; P = .001) and had incremental value for all-cause mortality over clinical and echocardiographic parameters.

CONCLUSIONS

In contemporary STEMI patients, prolonged LVMD was associated with various clinical and echocardiographic parameters. Prolonged LVMD was associated with worse long-term outcome.

Procedural-related coronary atrial branch occlusion during primary percutaneous coronary intervention for ST-segment elevation myocardial infarction and atrial arrhythmias at follow-up

OBJECTIVES

To evaluate the frequency of procedural-related atrial branch occlusion in ST-segment elevation myocardial infarction (STEMI) patients and its association with atrial arrhythmias at 1-year follow-up.

BACKGROUND

Atrial ischemia due to procedural-related coronary atrial branch occlusion in elective percutaneous coronary intervention (PCI) has been associated with atrial arrhythmias. Its role in a STEMI scenario is unknown.

METHODS

STEMI patients treated with primary PCI were classified according to the loss or patency of an atrial branch at the end of the procedure. The occurrence of atrial arrhythmias was documented on 24-hr Holter-ECG at 3 and 6 months or on ECG during 1-year follow-up visits.

RESULTS

Of 900 patients, 355 (age 61 ± 12 years, 79% male) underwent primary PCI involving the origin of an atrial branch. Procedural-related coronary atrial branch occlusion was observed in 18 (5%) individuals). During 1-year follow-up, 33% of patients with procedural-related atrial branch occlusion presented atrial arrhythmias, as compared with 55% in those with a patent atrial branch (p = .088). Age, no previous history of myocardial infarction, and a reduced flow in the culprit vessel were the only independent correlates of atrial arrhythmias.

CONCLUSIONS

The frequency of procedural-related atrial branch occlusion during primary PCI is low (5%) and is not associated with increased frequency of atrial arrhythmias at 1-year follow-up.

Left ventricular remodelling after ST-segment elevation myocardial infarction: sex differences and prognosis

Aims

Left ventricular (LV) remodelling after ST‐segment elevation myocardial infarction (STEMI) worsens outcome. The effect of sex on LV post‐infarct remodelling is unknown. We therefore investigated the sex distribution and long‐term prognosis of LV post‐infarct remodelling after STEMI in the contemporary era of primary percutaneous coronary intervention (PCI) and optimal pharmacotherapy.

Methods and results

Data were obtained from an ongoing primary PCI STEMI registry. LV remodelling was defined as ≥20% increase in LV end‐diastolic volume at either 3, 6, or 12 months post‐infarct, and LV remodelling impact on outcome was evaluated with a log‐rank test. A total population of 1995 STEMI patients were analysed (mean age 60 ± 12 years): 1527 (77%) men and 468 (23%) women. The mean age of male patients was 60±11 versus 63±13 years for women (P < 0.001). A total of 953 (48%) patients experienced LV remodelling in the first 12 months of follow‐up, and it was equally frequent amongst men (n = 729, 48%) and women (n = 224, 48%). After a median follow‐up of 94 (interquartile range 69–119) months, 225 patients died: 171 (11%) men and 54 (12%) women. No survival difference was seen between remodellers and non‐remodellers in the male (P = 0.113) and female (P = 0.920) groups.

Conclusion

LV post‐infarct remodelling incidence, as well as long‐term survival of LV remodellers and non‐remodellers, was similar in men and women who were treated with primary PCI and optimal pharmacotherapy post‐STEMI.

Prognostic Implications of Right Ventricular Free Wall Longitudinal Strain in Patients With Significant Functional Tricuspid Regurgitation

Background In patients with significant functional tricuspid regurgitation, timely detection of right ventricular (RV) dysfunction with conventional 2-dimensional echocardiography is challenging, whereas speckle-tracking echocardiography RV free wall longitudinal strain has been proposed as better prognosticator. We evaluated the prevalence and prognostic value of impaired RV free wall longitudinal strain in patients with significant functional tricuspid regurgitation, in comparison with tricuspid annular plane systolic excursion (TAPSE) and fractional area change (FAC). Methods Eight hundred ninety-six patients (51.3% men, 71 years [62-78 years]) with significant functional tricuspid regurgitation were divided according to the presence of RV dysfunction (defined as TAPSE <17 mm, FAC <35%, and RV free wall longitudinal strain >-23%) and were followed for the occurrence of all-cause mortality. Results RV free wall longitudinal strain identified the highest percentage of RV dysfunction (84.9%), in comparison to FAC (48.5%) and TAPSE (71.7%). During a median follow-up of 2.8 years (1.3-5.4 years), 443 (49.4%) patients died. Compared with survivors, nonsurvivors showed worse RV systolic dysfunction (FAC=36.5±12.7% versus 33.9±11.8%, P=0.001; TAPSE=15.4±5.0 versus 14.0±4.5 mm, P<0.001; RV free wall longitudinal strain=-15.9±7.5% versus -12.9±6.8%, P<0.001). Cumulative event-free survival was significantly worse in patients with decreased FAC, decreased TAPSE, and impaired RV free wall longitudinal strain. On multivariate analysis, RV free wall longitudinal strain was independently associated with all-cause mortality and incremental to FAC and TAPSE. Conclusions In significant tricuspid regurgitation, impaired RV free wall longitudinal strain identifies higher rates of RV dysfunction and is associated with worse outcome beyond conventional echocardiographic parameters of RV systolic function.

Association of Left Ventricular Global Longitudinal Strain With Asymptomatic Severe Aortic Stenosis: Natural Course and Prognostic Value

Importance

The optimal timing to operate in patients with asymptomatic severe aortic stenosis (AS) remains controversial. Left ventricular global longitudinal strain (LV GLS) may help to identify patients who might benefit from undergoing earlier aortic valve replacement.

Objective

To investigate the prevalence of impaired LV GLS, the natural course of LV GLS, and its prognostic implications in patients with asymptomatic severe AS with preserved left ventricular ejection fraction (LVEF).

Design, Setting, and Participants

This registry-based study included the institutional registries of 3 large tertiary referral centers and 220 patients with asymptomatic severe AS and preserved LVEF (>50%) who were matched for age and sex with 220 controls without structural heart disease. The echocardiograms of patients and controls were performed between 1998 and 2017.

Exposures

Both clinical and echocardiographic data were assessed retrospectively. Severe AS was defined by an indexed aortic valve area less than 0.6 cm2/m2. Left ventricular global longitudinal strain was evaluated on transthoracic echocardiography using speckle tracking imaging.

Main Outcomes and Measures

The prevalence of impaired LV GLS, the natural course of LV GLS, and the association of impaired LV GLS with symptom onset and the need for aortic valve intervention.

Results

Two hundred twenty patients (mean [SD] age, 68 [13] years; 126 men [57%]) were included. Despite comparable LVEF, LV GLS was significantly impaired in patients with asymptomatic severe AS compared with age- and sex-matched controls without AS (mean [SD] LV GLS, -17.9% [2.5%] vs -19.6% [2.1%]; P < .001). After a median follow-up of 12 (interquartile range, 7-23) months, mean (SD) LV GLS significantly deteriorated (-18.0% [2.6%] to -16.3% [2.8%]; P < .001) while LVEF remained unchanged. Patients with impaired LV GLS at baseline (>-18.2%) showed a higher risk for developing symptoms (P = .02) and needing aortic valve intervention (P = .03) at follow-up compared with patients with more preserved LV GLS (≤-18.2%).

Conclusions and Relevance

Subclinical myocardial dysfunction that is characterized by impaired LV GLS is often present in patients with asymptomatic severe AS with preserved LVEF. Left ventricular global longitudinal strain further deteriorates over time and impaired LV GLS at baseline is associated with an increased risk for progression to the symptomatic stage and the need for aortic valve intervention.

ST-Segment Elevation Myocardial Infarction in Patients With Chronic Obstructive Pulmonary Disease: Prognostic Implications of Right Ventricular Systolic Dysfunction as Assessed with Two-Dimensional Speckle-Tracking Echocardiography

BACKGROUND

Right ventricular (RV) systolic function in patients admitted with ST-segment elevation myocardial infarction (STEMI) with chronic obstructive pulmonary disease (COPD) and its impact on prognosis have not been characterized. The present study aims to compare the prevalence of RV systolic dysfunction in COPD versus non-COPD patients with STEMI and evaluate the prognostic implications.

METHODS

One hundred seventeen STEMI patients with COPD with transthoracic echocardiography performed within 48 hours of admission were retrospectively selected. Matched on age, gender, and infarct size (determined by cardiac biomarkers and left ventricular ejection fraction [LVEF]), 207 non-COPD patients were selected. RV dysfunction was defined based on tricuspid annular plane systolic excursion <17 mm (TAPSE), tricuspid annular systolic velocity <6 cm/s (S'), RV fractional area change <35% (FAC), and RV longitudinal free wall strain (FWSL) measured with speckle-tracking echocardiography >-20%. Patients were followed for the occurrence of all-cause mortality.

RESULTS

RV assessment was feasible in 112 COPD and 199 non-COPD patients (mean age, 69 ± 10; 74% male; mean, LVEF 47% ± 8%). Patients with COPD had significantly lower RV FAC (38% ± 11% vs 40% ± 9%; P = .04), equal TAPSE and S' (17.9 ± 3.7 vs 18.1 ± 3.8 mm, P = .72; and 8.4 ± 2.2 vs 8.5 ± 2.2 cm/sec, P = .605, respectively) and more impaired RV FWSL (-21.1% ± 6.6% vs -23.4% ± 6.5%, P = .005), compared with patients without COPD. RV dysfunction was more prevalent in patients with COPD, particularly when assessed with RV FWSL (46% vs 32%; P = .021). During a median follow-up of 30 (interquartile range 1.5-44) months, 49 patients died (16%). Multivariate models stratified for COPD status showed that RV FWS >-20% was independently associated with 5-year all-cause mortality (hazard ratio, 2.05; 95% CI, 1.12-3.76; P = .020), after adjusting for age, diabetes, peak troponin level, and LVEF. Interestingly, RV FAC < 35%, S'< 6 cm/sec, and TAPSE < 17 mm were not independently associated with survival.

CONCLUSION

In a STEMI population with relatively preserved LVEF, COPD patients had significantly worse RV FWSL compared with patients without COPD. Moreover, RV FWSL > -20% was independently associated with worse survival. In contrast, conventional parameters were not associated with survival.

Global Left Ventricular Myocardial Work Efficiency in Healthy Individuals and Patients with Cardiovascular Disease

BACKGROUND

Global left ventricular (LV) myocardial work efficiency, the ratio of constructive to wasted work in all LV segments, reflects the efficiency by which mechanical energy is expended during the cardiac cycle. Global LV myocardial work efficiency can be derived from LV pressure-strain loop analysis incorporating both noninvasively estimated blood pressure recordings and echocardiographic strain data. The aim of this study was to characterize global LV myocardial work efficiency in healthy individuals and patients with cardiovascular (CV) risk factors or overt cardiac disease.

METHODS

We retrospectively included healthy individuals without structural heart disease or CV risk factors, who were selected from an ongoing database of normal individuals, and matched for age and sex with (1) individuals without structural heart disease but with CV risk factors, (2) postinfarct patients without heart failure, and (3) heart failure patients with reduced ejection fraction (HFrEF). Global LV myocardial work efficiency was estimated with a proprietary algorithm from speckle-tracking strain analyses, as well as noninvasive blood pressure measurements.

RESULTS

In total, 120 individuals (44% male, 53 ± 13 years) were included (n = 30 per group). In healthy individuals without structural heart disease or CV risk factors, global LV myocardial work efficiency was 96.0% (interquartile range, 95.0%-96.3%). Myocardial efficiency of the LV did not differ significantly between individuals without structural heart disease and those with CV risk factors (96.0% vs 96.0%; P = .589). Global LV myocardial work efficiency, however, was significantly decreased in postinfarct patients (96.0% vs 93.0%, P < .001) and in those with HFrEF (96.0% vs 69.0%; P < .001).

CONCLUSIONS

While global LV myocardial work efficiency was similar in normal individuals and in those with CV risk factors, it was decreased in postinfarct and HFrEF patients. The global LV myocardial work efficiency values presented here show distinct patterns in different cardiac pathologies.

Effect of Guideline-Based Therapy on Left Ventricular Systolic Function Recovery After ST-Segment Elevation Myocardial Infarction

Little is known about the proportion of ST-segment elevation myocardial infarction (STEMI) patients treated with primary percutaneous coronary intervention, who have reduced left ventricular ejection fraction (LVEF) within 48 hours (baseline) of admission and exhibit LVEF recovery under optimal guideline-based medical treatment. Therefore, the present study evaluates the evolution of LVEF in patients after STEMI and under guideline-based medical therapy. In 2,853 STEMI patients treated with primary percutaneous coronary intervention, echocardiography was performed at baseline and at 6 months follow-up. Patients with previous myocardial infarction, reinfarction, coronary artery bypass grafting or incomplete echocardiographic data at 6 months follow-up were excluded. Reduced LVEF at baseline was defined as <40%. LVEF recovery was defined as LVEF >50% at 6 months follow-up. The prevalence of LVEF <40% at baseline was 13% (n = 371 patients; mean age 60 [range 33 to 88] years; 76% men). At follow-up, 31% of patients remained with a LVEF <40%, 30% showed a LVEF between 41% and 49% and in 39% of patients LVEF improved to >50%. There were no differences in usage of guideline-based medications at discharge across groups. On multivariable analysis, peak troponin T levels (odds ratio [OR] 0.895; p < 0.001), baseline LVEF (OR 1.069; p = 0.023) and absence of significant mitral regurgitation (OR 0.376; p = 0.018) were independently associated with LV recovery at follow-up. In conclusion, the prevalence of LVEF <40% is low. With optimal medical therapy, LVEF normalizes in 39% of patients. Smaller enzymatic infarct size, baseline LVEF and absence of mitral regurgitation were independently associated with LVEF recovery at follow-up.

Relation of Echocardiographic Markers of Left Atrial Fibrosis to Atrial Fibrillation Burden

In patients with atrial fibrillation (AF), left atrial (LA) fibrosis is a major determinant of the progression to, and burden of AF. LA reservoir strain and total atrial conduction time (PA-TDI) reflect LA fibrotic content. We aimed to investigate the relation between LA reservoir strain and PA-TDI in AF patients and control subjects. Six-hundred two patients (mean age 56 years, 53% men) with first episode of AF and 342 controls (mean age 64 years, 71% men) without structural heart disease underwent echocardiography. LA volumes, PA-TDI, LA reservoir strain, and left ventricular global longitudinal strain (GLS) were compared. Compared with controls, patients with paroxysmal AF and patients with persistent AF had longer PA-TDI (128 ± 25 millisecond, 140 ± 31 millisecond, and 154 ± 33 millisecond, respectively; p <0.001) and a progressive decline in LA reservoir strain (36.9 ± 11.6%, 29.8 ± 13.4%, 24.2 ± 12.3%, respectively; p <0.001). LA reservoir strain was negatively correlated with PA-TDI (r = -0.43, p <0.001). On multivariate analyses, LA reservoir strain, diabetes mellitus, and burden of AF were independent correlates of PA-TDI (R² = 0.23, p <0.001); whereas only PA-TDI was an independent correlate of LA reservoir strain (R² = 0.43, p <0.001); controlling for age, hypertension, coronary artery disease, body mass index, severity of mitral regurgitation, left ventricular global longitudinal strain, and LA volume. In conclusion, PA-TDI and LA reservoir strain are negatively correlated in all subjects, irrespective of the presence or burden of AF. Patients with persistent AF have longer PA-TDI and impaired LA reservoir strain compared with paroxysmal AF and controls, suggesting increasing burden of fibrosis and LA structural remodeling in the progression of AF.

Prognostic value of global longitudinal strain in heart failure patients treated with cardiac resynchronization therapy

BACKGROUND

Myocardial fibrosis (macroscopic scar or diffuse reactive fibrosis) is one of the determinants of impaired left ventricular (LV) global longitudinal strain (GLS) in heart failure (HF) patients.

OBJECTIVE

The purpose of this study was to evaluate the prognostic value of LV GLS in HF patients treated with cardiac resynchronization therapy (CRT).

METHODS

The study included 829 HF patients (mean age 64.6 ± 10.4 years; 72% men) treated with CRT. Before CRT implantation, LV GLS was assessed using 2-dimensional speckle tracking echocardiography. The primary endpoint was the combination of all-cause mortality, heart transplantation, and LV assist device implantation. The secondary endpoint was the occurrence of ventricular arrhythmias or appropriate implantable defibrillator device therapies.

RESULTS

During follow-up, 332 patients reached the primary endpoint, and 233 presented with the secondary endpoint. Patients were divided according to LV GLS quartiles. Patients with the most impaired LV GLS quartile had a 2-fold higher risk of reaching the combined endpoint compared with patients in the best LV GLS quartile (hazard ratio [HR] 2.088; 95% confidence interval [CI] 1.555-2.804; P <.001). LV GLS was significantly associated with the combined endpoint (HR 1.075; 95% CI 1.020-1.133; P = .007) after adjusting for clinical, electrocardiographic, and echocardiographic characteristics. Although patients in the most impaired LV GLS quartile showed higher event rates for the secondary endpoint compared with the other groups, LV GLS was not independently associated with the secondary endpoint (HR 1.047; 95% CI 0.989-1.107; P = .115).

CONCLUSION

In this large cohort of CRT patients, baseline LV GLS was independently associated with the combined endpoint.

Influence of Aging on Level and Layer-Specific Left Ventricular Longitudinal Strain in Subjects Without Structural Heart Disease

Values for level- (apical, mid, and basal) and layer-based (endocardial, mid-myocardial, and epicardial) left ventricular (LV) longitudinal strain across age are scarce. The present study evaluates the effect of aging on level- and layer-specific LV longitudinal strain in subjects without structural heart disease. A total of 408 subjects (mean age 58 years [range 16 to 91]; 49% men) were evaluated retrospectively. Subjects were divided into equal groups based on age and gender. Subjects with evidence of structural heart disease or arrhythmias were excluded. Mean LV ejection fraction was 62 ± 6.2%. A gradual increase in magnitude of level LV longitudinal strain was observed from basal to mid and apical levels (-16.7 ± 2.1%, -18.8 ± 2.0%, -22.6 ± 3.8%; p <0.001, respectively). Across age groups, there was a borderline significant decrease in magnitude of basal longitudinal strain in older subjects, whereas the magnitude in the apical level significantly increased. On layer-based analysis, the magnitude of longitudinal strain increased from epicardium to endocardium across all age groups. On multivariable analysis, only diabetes mellitus was associated with more impaired longitudinal strain in the endocardium, and male gender was associated with more impaired longitudinal strain at the epicardium layer. In conclusion, with increasing age, the magnitude of LV longitudinal strain at the basal level declines while the apical LV longitudinal strain increases. In contrast, layer-specific LV longitudinal strain remains unchanged with aging. The presence of diabetes mellitus modulated the effect of age on the LV endocardial layer, and male gender was associated with more impaired longitudinal strain at the epicardial layer.

Prevalence of left ventricular systolic dysfunction in pre-dialysis and dialysis patients with preserved left ventricular ejection fraction

AIMS

Patients with chronic kidney disease (CKD) have an excess of cardiovascular morbidity and mortality, with heart failure (HF) being particularly frequent. Reduced left ventricular ejection fraction (LVEF) defines left ventricular (LV) systolic dysfunction and is associated with poor prognosis. However, CKD patients may have HF symptoms with preserved LVEF. In this subgroup of patients, two-dimensional speckle tracking echocardiography can detect LV systolic dysfunction by analysing LV myocardial deformation. The present study evaluated the prevalence of impaired LV global longitudinal strain (GLS) in CKD patients with preserved LVEF and its prognostic consequences.

METHODS AND RESULTS

Overall, 200 pre-dialysis and dialysis patients (65% men, mean age 60 ± 14 years) with CKD stage 3b-5 and preserved LVEF (≥50%) were evaluated. Left ventricular systolic dysfunction despite preserved LVEF was defined by LV GLS ≤15.2% (cut-off value derived from two standard deviations below the mean value of individuals without structural heart disease). Impaired LV GLS (≤15.2%) despite preserved LVEF was observed in 32% of patients. During a median follow-up of 33 months (interquartile range 17-62 months), 47% of patients underwent renal transplantation, 9% were admitted with HF, and 28% died. Patients with LV GLS ≤15.2% showed significantly worse cumulative event-free survival rates of the combined endpoint of HF hospitalization and all-cause mortality compared to patients with LV GLS >15.2% (log-rank P = 0.018).

CONCLUSION

The prevalence of impaired LV GLS despite preserved LVEF in pre-dialysis and dialysis patients is relatively high. Patients with preserved LVEF but impaired LV GLS have an increased risk of HF hospitalization and all-cause mortality.

Comparison of Left Ventricular Function and Myocardial Infarct Size Determined by 2-Dimensional Speckle Tracking Echocardiography in Patients With and Without Chronic Obstructive Pulmonary Disease After ST-Segment Elevation Myocardial Infarction

Patients with chronic obstructive pulmonary disease (COPD) have a high risk of mortality after acute ST-segment elevation myocardial infarction (STEMI). We compared STEMI patients with versus without COPD in terms of infarct size and left ventricular (LV) systolic function using advanced 2-dimensional speckle tracking echocardiography. Of 1,750 patients with STEMI (mean age 61 ± 12 years, 76% male), 133 (7.6%) had COPD. With transthoracic echocardiography, left ventricular ejection fraction (LVEF) and wall motion score index were measured. Infarct size was assessed using biomarkers (creatine kinase and troponin T). LV global longitudinal strain (GLS), reflecting active LV myocardial deformation, was measured with 2-dimensional speckle tracking echocardiography to estimate LV systolic function and infarct size. STEMI patients with COPD were significantly older, more likely to be former smokers, and had worse renal function compared with patients without COPD. There were no differences in infarct size based on peak levels of creatine kinase (1315 [613 to 2181] vs 1477 [682 to 3047] U/l, p = 0.106) and troponin T (3.3 [1.4 to 7.3] vs 3.9 [1.5 to 7.8] µg/l, p = 0.489). Left ventricular ejection fraction (46% vs 47%, p = 0.591) and wall motion score index (1.38 [1.25 to 1.66] vs 1.38 [1.19 to 1.69], p = 0.690) were comparable. In contrast, LV GLS was significantly more impaired in patients with COPD compared with patients without COPD (-13.9 ± 3.0% vs -14.7 ± 3.9%, p = 0.034). In conclusion, despite comparable myocardial infarct size and LV systolic function as assessed with biomarkers and conventional echocardiography, patients with COPD exhibit more impaired LV GLS on advanced echocardiography than patients without COPD, suggesting a greater functional impairment at an early stage after STEMI.