Acute myocardial infarction due to giant coronary artery aneurysm and arteriovenous fistula: a challenging case report and review of the literature

BACKGROUND

A coronary artery aneurysm (CAA) is an abnormal dilation of a coronary artery segment often accompanied by coronary artery fistula (CAF), leading to communication between a coronary artery and a cardiac chamber or a part of the coronary venous system. Both CAAs and CAFs can present with symptoms and signs of myocardial ischemia and infarction.

CASE PRESENTATION

We describe the case of a 46-year-old woman with non-ST-elevation myocardial infarction (NSTEMI) caused by a "giant" CAA. Various imaging modalities revealed a thrombus-containing aneurysm located at the right-posterior cardiac border, with established arteriovenous communication with the distal part of left circumflex artery (LCx). After initial treatment with dual antiplatelet therapy, a relapse of pain was reported along with a new increase in troponin levels, electrocardiographic abnormalities, reduced left ventricular ejection fraction (LVEF) and thrombus enlargement. Surgical excision of the aneurysm was favored, revealing its true size of 6 cm in diameter. Τhe aneurysm was excised without complications. The patient remained asymptomatic during follow-up.

CONCLUSIONS

Management of rare entities such as "giant" CAAs and CAFs can be challenging. Cases such as this can serve as precedents to facilitate treatment plans and develop consistent recommendations, emphasizing the importance of personalized strategies for future patients.

Diagnostic Puzzles and Cause-Targeted Treatment Strategies in Myocardial Infarction with Non-Obstructive Coronary Arteries: An Updated Review

Myocardial infarction with nonobstructive coronary arteries (MINOCA) is a distinct subtype of myocardial infarction (MI), occurring in about 8-10% of spontaneous MI cases referred for coronary angiography. Unlike MI with obstructive coronary artery disease, MINOCA's pathogenesis is more intricate and heterogeneous, involving mechanisms such as coronary thromboembolism, coronary vasospasm, microvascular dysfunction, dissection, or plaque rupture. Diagnosing MINOCA presents challenges and includes invasive and non-invasive strategies aiming to differentiate it from alternative diagnoses and confirm the criteria of elevated cardiac biomarkers, non-obstructive coronary arteries, and the absence of alternate explanations for the acute presentation. Tailored management strategies for MINOCA hinge on identifying the underlying cause of the infarction, necessitating systematic diagnostic approaches. Furthermore, determining the optimal post-MINOCA medication regimen remains uncertain. This review aims to comprehensively address the current state of knowledge, encompassing diagnostic and therapeutic approaches, in the context of MINOCA while also highlighting the evolving landscape and future directions for advancing our understanding and management of this intricate myocardial infarction subtype.

Syncopal patients without prodromes exhibit a diverse pattern of adenosine release during head-up tilt test

Background/Introduction

In a significant proportion of patients with neurally-mediated syncope (NMS), the mechanism of syncope remains largely undetermined. Adenosine has been proposed as a central humoral factor in various forms of NMS: high Adenosine Plasma Levels (ADP) are encountered in patients with vasovagal syncope (VVS), low ADP in non-prodromes syncope (NPS), while ADP in patients with situational syncope SS are less well determined.

Purpose

We sought to assess ADP in patients with different clinical forms of syncope, with an emphasis on the presence or absence of prodromal symptoms, as well as the relation between ADP and the outcomes of Head-Up Tilt Table Test (HUTT) and Adenosine test (ADT).

Methods

Patients with different clinical types of NMS (n=124), i.e., VVS, NPS, or SS, were investigated using a standard protocol including HUTT and ADT. During HUTT, ADP was measured in the supine position, at table tilting, and in syncope.

Results

Baseline ADP did not differ among groups. ADP at syncope were higher in NPS compared to VVS (1.55±1.29 vs 0.16±0.05 μM, p=0.03) and SS (0.15±0.05 μM, p=0.02). In NPS, ADP increased from the supine position to the time of syncope (0.47±0.25 to 1.55±1.29 μM, p=0.04). In VVS, ADP increased only from the supine to the tilt position (0.23±0.04 to 0.35±0.10 μMu, p=0.02), while in SS ADP did not change in any stage of HUTT. SS was associated with cardioinhibitory HUTT (OR 3.40, 95% CI 1.05 to 9.56, p=0.04) and positive ADT (OR 4.22, 95% CI 1.47 to 11.46, p=0.012).

Conclusion(s)

A distinct pattern of ADP increase is noted during HUTT in NPS, suggesting that an excessive increase of ADP may play the key role in triggering this type of clinical presentation of syncope independently of the baseline ADP. Cardioinhibition prevails in patients with SS without clear adenosine involvement. Such observations contribute to an enhanced understanding of the pathophysiology of different clinical forms of syncope which may offer the possibility to tailor the management approach appropriately.

Funding Acknowledgement

Type of funding sources: None.

Total atrial conduction time and its relationship with morphological & functional characteristics in hypertrophic cardiomyopathy

Funding Acknowledgements

Type of funding sources: None.

Background

Total atrial conduction time (TACT), estimated by tissue Doppler imaging (TDI), is an index reflecting left atrial (LA) structural and electrical remodeling, connected to atrial fibrillation (AF) development and heart failure progression in various substrates. In hypertrophic cardiomyopathy (HCM), the significance of TACT beyond AF and its determinants are not fully investigated.

Purpose

Aim of this study was to estimate TACT in a cohort of HCM patients without AF history and to examine its relationship with other parameters of atrial myopathy, such as LA volume index (LAVI) or LA reservoir strain (LARS). Additionally, to investigate TACT correlation with other phenotypic and functional characteristics of HCM.

Methods

 We included 50 HCM patients (60 ± 16 years, 80% male, maximum wall thickness 18.6 ± 4.1mm) without history of AF who have consecutively undergone 2D-speckle tracking echocardiography and cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE). TACT was measured from the onset P wave on electrocardiogram to the peak A’ wave of the lateral LA wall using TDI (left panel). Burden of fibrosis (percentage of LV mass) was defined by LGE extent (>5 standard deviations compared to nulled myocardium) in CMR slices. Cut-off points for TACT, LAVI and LARS were adopted by literature (≥115 msec, ≥34 mL/m2 and <21.3 % respectively).

Results

 All HCM patients had preserved EF (61.8 ± 8%), while 13 (26%) presented outflow tract obstruction and 4 (8%) diastolic dysfunction stage≥2. LGE was observed in 32 patients (64%) occupying 7.2 ± 5% of left ventricular (LV) mass. Mean TACT was 139.9 ± 22 msec, with LAVI being 30.8 ± 16.1 mL/m2 and LARS 27.6 ± 13.9%. After assessing prevalence of atrial myopathy parameters, 41 patients (82%) presented a prolonged (≥115 msec) TACT with only 13 of them having also a significantly dilated LA (≥34 mL/m2) and 16 an impaired LARS. Among HCM demographic, phenotypic and functional characteristics tested, age and LV mass index were found to be the only independent regressors of TACT (r = 0.54, p < 0.0005 and r = 0.44, p = 0.002 respectively, right panels). On the contrary, no significant correlation was established between TACT and traditional diastolic dysfunction indices such as E/E’ or fibrosis extent.

Conclusions

Atrial electro-mechanical delay assessed through TDI based TACT, is very frequent among HCM patients irrespective of AF and even before LA dilatation and LA strain impairment.  Age and hypertrophy magnitude are the main determinants of TACT, the prognostic significance of which remains to be further elucidated. Abstract Figure.

Strain-volume loops for assessment of diastolic function in hypertrophic cardiomyopathy

Funding Acknowledgements

Type of funding sources: None.

Background

Diastolic function assessment in patients with hypertrophic hearts and preserved ejection fraction (EF) is a rather challenging task, necessitating the introduction of new parameters. Strain-volume loops (SVLs), based on simultaneous frame-by-frame strain and volume changes’ recordings acquired by means of three-dimensional (3D) speckle tracking imaging, is an innovative tool which has been applied in various substrates. The ability of SVLs to assess diastolic function in hypertrophic cardiomyopathy (HCM) has not been investigated until now.

Purpose

Aim of this study was to investigate potential correlations between SVLs, traditional diastolic function indices and phenotypic features of HCM (thickness, obstruction and fibrosis) that may also reflect myocardial "stiffness".

Methods

 We included 40 HCM patients (54.1 ± 14.3 years, 82.5% male, maximum wall thickness 19.3 ± 4.8mm) who have consecutively undergone 3D-speckle tracking echocardiography (panel A) and cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE). Values of 3D strain were plotted vs. volume for each frame to build an SVL. Peak of radial, longitudinal and circumferential systolic strain (Rsp, Lsp, and Csp, respectively), systolic slopes of the loops (RsSl, LsSl, CsSl), strain to end-diastolic volume (EDV) ratios (Rs/V, Ls/V, Cs/V) as well as the extent of systolic-diastolic uncoupling (difference between systolic and diastolic strain for the same volume) were computed for the analysis. Left atrial volume index (LAVI), E/E’ and tricuspid regurgitation velocity (TRvel) were measured to define diastolic dysfunction (DD) stage. Burden of fibrosis was evaluated by LGE extent in CMR slices.

Results

 All HCM patients had preserved EF (60.5 ± 5,7%), while 16 (40%) had LV outflow tract obstruction (LVOTO > 30 mm Hg at rest). Mean LV mass index was 78.9 ± 14.5 g (evaluated by 3D echocardiography). LGE was observed in 23 patients (57.5%) occupying 5.2 ± 4.5% of LV mass. Concerning SVLs the following values were recorded for radial (Rsp 30.8 ± 9.8%, RsSl 0.4 ± 0.13 and Rs/V 0.25 ± 0.09), longitudinal (Lsp -9.4 ± 3.7%, LsSl 0.12 ± 0.06 and Ls/V 0.08 ± 0.04) and circumferential deformation (Csp -14.2 ± 3.5%, CsSl 0.18 ± 0.05 and Cs/V 0.11 ± 0.03). Traditional isolated diastolic indices (E/E’, LAVI, TRvel and DD stage) did not present significant correlations with SVL parameters or HCM phenotypic features. However, potentially "stiffer" hearts (combination of increased LVMI and fibrosis) presented a leftward transition of longitudinal SVLs, which also became wider (greater uncoupling) (panel B).

Conclusions

Traditional diastolic indices show modest only correlations with SVLs or HCM phenotypic characteristics, necessitating new approaches to DD of HCM patients. SVLs seem to be a promising-innovative tool for indirect assessment of myocardial "stiffness" and diastolic function. Abstract Figure.

Adenosine plasma levels and adenosine receptor levels determine the outcome of adenosine test and head-up tilt test in syncopal patients with a normal heart

Background/Introduction

The neurohumoral profile underlying the manifestation of reflex syncope remains incompletely understood. Adenosine plasma (ADP) and adenosine receptor (ADR) levels may differentiate the outcomes of head-up tilt table test (HUTT) and adenosine test (ADT) but their role in the diagnostic evaluation of patients with syncope has yet to be determined.

Purpose

We sought to assess the ADP and ADR levels in patients without structural heart disease who underwent HUTT and ADT tests as part of the diagnostic workup of syncope. We specifically investigated differences in the outcomes of the HUTT and ADT tests as well as to the ADP levels during HUTT.

Methods

HUTT and ADT were performed as per the standard protocols. ADT was considered positive in the event of asystole >6 seconds or heart block for >10 seconds after intravenous Adenosine 0.15 mg/kg administration in the supine position. ADP levels were assessed at three timepoints during the HUTT: at baseline (supine), immediately after bed tilt and, in cases of a positive HUTT, at the time of syncope. Patients were categorized in quintiles of very low, low, intermediate, high and very high baseline ADP levels. We also assessed the A2A ADR levels of monocytes.

Results

We prospectively analyzed 124 patients (71 women, age 46.78±21.01 years). ADT was positive in 12.9% of patients and HUTT in 44.4% of patients. Patients with very low baseline ADP levels (lowest quintile) more frequently presented with a positive ADT (odds ratio [OR] 4.08, 95% Confidence Interval [CI] 1.40 to 13.13, p<0.05). Baseline ADP did not differ between patients with positive and negative HUTT. However, patients with vasodepressor response to HUTT exhibited increase in ADP from baseline to bed tilt (0.33±1.03 vs. 0.42±1.14 ppm/Um/L, p<0.05) and in syncope (0.70±1.89, P<0.05), while no difference was noted in patients with cardioinhibitory or mixed response. Patients with positive ADT and negative HUTT had higher ADR levels (221.5±88.56 MFI) as compared to patients with negative ADT and positive HUTT (59.78±83.65 MFI, p<0.05) and to patients with positive ADT and HUTT (33.29±35.77 MFI, p<0.05). Within patients with positive HUTT, those with onset of syncope in the Isoprenaline provocation phase (>20 min) had lower ADR levels (80.88±238.98 vs 89.43±96.08 MFI, p<0.05).

Conclusion(s)

Baseline ADP levels are related to the outcome of ADT while an ADP increase immediately after bed tilt and in syncope is evident in vasodepressor response to HUTT. Higher ADR levels are related to positive ADT and negative HUTT. Lower ADR levels are associated with more delayed onset of syncope during HUTT. ADP and ADR levels warrant further investigation as they may characterize a subset of patients with specific responses to ADT and HUTT and may be implicated in the pathophysiology of reflex syncope.

Funding Acknowledgement

Type of funding sources: None.

Effect of sodium-glucose co-transporter 2 inhibitors on left ventricular mass and left atrial volume indices assessed either by cardiovascular magnetic resonance or transthoracic echocardiography

Background

Sodium-glucose co-transporter 2 (SGLT-2) inhibitors are a novel class of antidiabetic regimens linked with a significant reduction in the risk for surrogate cardiovascular and renal outcomes. Specific patient populations, for example subjects with heart failure with reduced ejection fraction (HFrEF), also benefit from this drug class, regardless the presence of T2DM. Left ventricular (LV) hypertrophy is a strong, independent predictor of cardiovascular morbidity and mortality; left atrial volume index (LAVI), an indicator of severity of LV diastolic dysfunction and filling properties, has been shown to predict “hard” cardiovascular outcomes among patients with T2DM, while it might predict the recovery of left ventricular ejection fraction in patients with HFrEF.

Purpose

We sought to determine the effect of SGLT-2 inhibitors on the above indices, in order to evaluate additional cardioprotective mechanisms of this drug class.

Methods

We searched 2 major electronic databases (PubMed and Cochrane/CENTRAL) along with grey literature sources for parallel-group RCTs investigating the effect of SGLT-2 inhibitors compared to placebo or active control on LV mass, LV mass index (LVMI) and LAVI, evaluated either by TTE or CMR, on adult patients regardless the presence of T2DM or HF.

Results

After screening the potentially eligible records, 9 studies were included in our analysis with a total of 843 patients. Treatment with SGLT-2 inhibitors compared to placebo or active control leads to a statistically significant decrease in LV mass by 6.01 g (95% CI −11.33 to −0.69, I2=76%) (Figure 1a). A significant decrease in LVMI by 2.61 g/m2 was observed (MD=−2.61, 95% CI −4.94 to −0.29, I2=65%) (Figure 1b). Of note, the effect on LAVI was marginally non-significant (MD=−1.51 ml/m2, 95% CI −3.05 to 0.03, I2=0%) (Figure 1c). Subgroup analysis for patients with HFrEF demonstrated a non-significant reduction in LV mass (MD=−11.72 g, 95% CI −30.61 to 7.16, I2=90%) and in LVMI (MD=−6.28 g/m2, 95% CI −30.61 to 0.25, I2=80%) (Figure 2a and 2b).

Conclusions

SGLT-2 inhibitors demonstrate a clear benefit on LV mass and LVMI, regardless of diabetes status, while a marginally non-significant effect is observed on LAVI. These results provide further insights into the cardioprotective mechanisms mediated by this drug class, besides those already established.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Beat-to-beat P-wave analysis outperforms conventional P-wave indices in identifying patients with a history of paroxysmal atrial fibrillation, during sinus rhythm

Introduction

Atrial fibrillation (AF) is the most common arrhythmia and is associated with high risk of morbidity and mortality. In many patients, AF is of episodic character (paroxysmal AF – PAF), which makes the identification of these patients during sinus rhythm (SR) challenging.

Purpose

The aim of the present study is to compare the performance of beat-to-beat P-wave analysis with P-wave indices used as predictors of PAF, such as P-wave duration, area, voltage, axis, terminal force in V1, inter-atrial block or orthogonal type, in identifying patients with history of PAF during sinus rhythm.

Methods

Standard 12-lead ECG and 10-minute orthogonal ECG recordings were obtained from 40 consecutive patients with short history of PAF under no antiarrhythmic medication and 60 age- and sex- matched healthy controls. The P-waves on the 10-minute recordings were analyzed on a beat-to-beat basis and classified as belonging to a primary or secondary morphology according to previous study. Wavelet transform used to further analyze P-wave orthogonal signals of main morphology on a beat-to-beat basis.

Results

38 out of 327 studied features were found to differ significantly among the two groups. These features were tested for their diagnostic ability and receiver operating characteristic curves were ploted. Only 3 of them performed adequetly, with an area under curve (AUC) above 0.65; Two of them came from morphology analysis (percentage of beats following main morphology in axis X and Y) and one from wavelet analysis (max energy in high frequency zone -Y axis). Among standard P-wave indices, P-wave area in lead II was the one with the highest AUC (0.64).

Conclusion

Novel indices derived from beat-to-beat analysis outperform stadard P-wave markers in identifying patients with PAF history during sinus rhythm.

Funding Acknowledgement

Type of funding sources: None. ROC curves of most significant featuresAUC characteristics of P-wave indices

Sodium-glucose co-transporter-2 inhibitors improve cardiovascular outcomes in heart failure with reduced ejection fraction regardless of ischemic etiology

Background

Coronary artery disease remains the main underlying cause of heart failure (HF), despite the progress in prevention, diagnosis and treatment. Sodium-glucose co-transporter-2 inhibitors have been shown to improve surrogate cardiovascular outcomes in patients with HF with reduced ejection fraction (HFrEF), regardless of diabetes status.

Purpose

We sought to determine the effect of SGLT-2 inhibitors on the primary composite endpoint (cardiovascular death or hospitalization for HF) across the two hallmark trials in the HFrEF population (EMPEROR Reduced and DAPA-HF), according to ischemic or non-ischemic etiology of HF.

Methods

We pooled data from EMPEROR reduced and DAPA-HF trials in a total of 8,474 patients with HFrEF, performing a sub-analysis according to the presence of ischemic cardiomyopathy as the underlying cause of HFrEF.

Results

Treatment with SGLT-2 inhibitors resulted in a significant decrease in the risk for the primary composite outcome in patients with HFrEF of ischemic etiology, equal to 18% (RR=0.82, 95% CI: 0.73–0.92, I2=0%). In patients with HFrEF of non-ischemic etiology, SGLT-2 inhibitors produced a significant decrease in the risk for the primary composite outcome equal to 18% (RR=0.72, 95% CI: 0.63–0.82, I2=0%). Despite the greater effect in patients with non-ischemic HFrEF, no subgroup difference was detected (p=0.16). Generated results are summarized in Figure 1.

Conclusions

SGLT-2 inhibitors improve surrogate cardiovascular outcomes both in patients with ischemic and non-ischemic HFrEF.

Funding Acknowledgement

Type of funding sources: None. Figure 1

Impact of antidiabetic treatment with dipeptidyl peptidase-4 inhibitors on the risk of cardiac arrhythmias among patients with type 2 diabetes mellitus

Introduction

Type 2 diabetes mellitus (T2DM) is considered as a global pandemic, comprising a significant, independent cardiovascular risk factor. Besides major adverse cardiovascular events, patients with T2DM experience an increased risk of heart rhythm disorders, nevertheless the exact mechanisms of arrhythmogenesis in the context of diabetes mellitus are still being under investigation. Dipeptidyl peptidase-4 (DPP-4) inhibitors represent a novel class of antidiabetic regimens with proved safety and efficacy among patients with T2DM and a series of randomized controlled trials (RCTs) addressing cardiovascular outcomes with DPP-4 inhibitors have been published. The exact effect of DPP-4 inhibitors on the arrhythmic burden among diabetic individuals is yet to be identified.

Purpose

In the present meta-analysis, we sought to determine the impact of antidiabetic treatment with DPP-4 inhibitors on the risk of various cardiac arrhythmias.

Methods

We searched PubMed for all published RCTs assessing cardiovascular outcomes after antidiabetic treatment with DPP-4 inhibitors. We extracted data regarding the risk for the following cardiac arrhythmias: atrial fibrillation, atrial flutter, atrial tachycardia, ventricular fibrillation, ventricular tachycardia, ventricular extrasystoles, supraventricular tachycardia, sinus node dysfunction, second degree atrioventricular block, complete atrioventricular block.

Results

Following a meticulous assessment of the available literature, we pooled data from 6 trials in a total of 52,520 patients. Antidiabetic treatment with DPP-4 inhibitors did not significantly affect the risk for atrial fibrillation (RR=0.95, 95% CI: 0.78–1.17, I2=0%) (Figure 1a). Of note, DPP-4 inhibitors were associated with a significant increase in the risk for atrial flutter, equal to 52% (RR=1.52, 95% CI: 1.03–2.24, I2=0%), as shown in Figure 2. Finally, DPP-4 inhibitors did not have a significant impact on the risk for any of the rest assessed major cardiac arrhythmias.

Conclusions

DPP-4 inhibitors do not seem to be associated with a significant risk for any major cardiac arrhythmias, except for atrial flutter.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Risk of death with sodium-glucose co-transporter-2 inhibitors across the hallmark cardiovascular and renal outcome trials: an updated meta-analysis

Background

Patients with type 2 diabetes mellitus (T2DM) experience a 15% increase in the risk for death compared to the general population, with age less than 55 years, insufficient glycemic control and albuminuria representing the major risk factors for all-cause and cardiovascular mortality. Despite progression in diagnosis and treatment, mortality remains elevated among affected individuals. Sodium-glucose co-transporter 2 (SGLT-2) inhibitors are considered as the optimal treatment option for patients with T2DM and concomitant cardiovascular or renal disease, while these regimens demonstrated a clear benefit in all-cause and cardiovascular mortality compared to placebo.

Purpose

As we recently welcomed the publication of large-scale randomized controlled trials (RCTs) with SGLT-2 inhibitors addressing surrogate, hard endpoints, we sought to perform an updated meta-analysis, investigating the effect of SGLT-2 inhibitors on all-cause, cardiovascular and renal death among the high- or very-high risk patients enrolled in those trials.

Methods

We pooled data from the relevant, recent hallmark RCTs; 10 trials were included in our analysis encompassing a total of 71,533 enrolled participants, assigned either to SGLT-2 inhibitor treatment or placebo. We set cardiovascular death as the primary efficacy outcome, while we assessed all-cause death and renal death as secondary efficacy outcomes.

Results

Treatment with SGLT-2 inhibitors resulted in a significant decrease in the risk of cardiovascular death, equal to 14% (RR = 0.86, 95% CI; 0.80 to 0.93, I2=22%). Only canagliflozin produced a significant result, while dapagliflozin led to a marginally non-significant reduction in cardiovascular mortality (Figure 1). Notably, SGLT-2 inhibitors led to a significant decrease in the risk for all-cause death, equal to 14% (RR=0.86, 95% CI; 0.81 to 0.92, I2=34%) the result was significant only for canagliflozin and dapagliflozin, while none of the rest SGLT-2 inhibitors resulted in a significant decrease in the risk for all-cause death (Figure 1). SGLT-2 inhibitors also produced a non-significant decrease in the risk for renal death (RR=0.36, 95% CI; 0.12 to 1.14, I2=0%). Neither canagliflozin nor dapagliflozin had a significant impact on risk reduction for renal death, while no cases of renal death were reported in VERTIS CV trial. No subgroup differences were identified for any of the three comparisons (Figure 2).

Conclusions

Antidiabetic treatment with SGLT-2 inhibitors provides a clear benefit in terms of cardiovascular and all-cause mortality for the very high-risk patients enrolled in the cardiovascular and renal outcome trials. Canagliflozin seems to be associated with the greatest impact on risk reduction for all-cause and cardiovascular death, followed by dapagliflozin.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Utility of volume-strain loops in diastolic function assessment of patients with hypertrophic cardiomyopathy

Background

Diastolic function assessment in patients with hypertrophic hearts and preserved ejection fraction (EF) is a rather challenging task. Combined plotting of deformation parameters against other indices, especially left ventricular (LV) volume, may reflect diastolic function components of the hypertrophic myocardium.

Purpose

Aim of this study was i) to apply strain-volume loops (SVLs) in hypertrophic cardiomyopathy (HCM) patients based on simultaneous frame-by-frame strain and volume changes' recordings acquired by means of three-dimensional (3D) speckle tracking imaging and ii) to investigate potential correlations between these loops, traditional diastolic function indices and phenotypic features of HCM (thickness, obstruction and fibrosis) that may also reflect myocardial “stiffness”.

Methods

We included 40 HCM patients (54.1±14.3 years, 82.5% male, maximum wall thickness 19.3±4.8mm) who have consecutively undergone 3D-speckle tracking echocardiography and cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE). Values of 3D strain were plotted vs. volume for each frame to build an SVL. Peak of radial, longitudinal and circumferential systolic strain (Rsp, Lsp, and Csp, respectively), systolic slopes of the loops (RsSl, LsSl, CsSl), strain to end-diastolic volume (EDV) ratios (Rs/V, Ls/V, Cs/V) as well as the extent of systolic-diastolic uncoupling (difference between systolic and diastolic strain for the same volume) (panel A) were computed for the analysis. Left atrial volume index (LAVI), E/E' and tricuspid regurgitation velocity (TRvel) were measured to define diastolic dysfunction (DD) stage. Burden of fibrosis was evaluated by LGE extent in CMR slices.

Results

All HCM patients had preserved EF (60.5±5,7%), while 16 (40%) had LV outflow tract obstruction (LVOTO>30 mm Hg at rest). Mean LV mass index was 78.9±14.5 g (evaluated by 3D echocardiography). LGE was observed in 23 patients (57.5%) occupying 5.2±4.5% of LV mass. Concerning SVLs the following values were recorded for radial (Rsp 30.8±9.8%, RsSl 0.4±0.13 and Rs/V 0.25±0.09), longitudinal (Lsp −9.4±3.7%, LsSl 0.12±0.06 and Ls/V 0.08±0.04) and circumferential deformation (Csp −14.2±3.5%, CsSl 0.18±0.05 and Cs/V 0.11±0.03). Traditional isolated diastolic indices (E/E', LAVI, TRvel and DD stage) did not present significant correlations with SVL parameters or HCM phenotypic features. However, potentially “stiffer” hearts (combination of increased LVMI and fibrosis) presented a leftward transition of longitudinal SVLs, which also became wider (greater uncoupling) (panel B).

Conclusions

Traditional diastolic indices show modest only correlations with SVLs or HCM phenotypic characteristics, necessitating new approaches to DD of HCM patients. SVLs seem to be a promising-innovative tool for indirect assessment of myocardial “stiffness” and diastolic function.

Funding Acknowledgement

Type of funding sources: None. Figure 1

Meta-analysis of cardiovascular outcome trials assessing the impact of glucagon-like peptide-1 receptor agonists on major cardiac arrhythmias

Background

Type 2 diabetes mellitus poses a significant health burden, whereas growing attention has been focused on the novel classes of antidiabetic drugs. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) constitute such a group of antidiabetic agents. In recent large, placebo-controlled randomized clinical trials (RCTs), GLP-1RAs have demonstrated beneficial cardiovascular effects. Nevertheless, the clear antiarrhythmic benefit has not been underlined yet.

Purpose

The purpose of the present analysis was to clarify the impact of antidiabetic treatment with GLP-1RAs on the several different types of cardiac arrhythmias, based on data extracted from relevant cardiovascular outcome trials.

Methods

We searched PubMed plus grey literature for all available cardiovascular and renal outcome, placebo-controlled RCTs utilizing GLP-1RAs versus placebo.

Results

We pooled data from 7 cardiovascular outcome trials with GLP-1RAs in a total of 55,943 randomized participants patients. When compared to placebo, treatment with GLP-1RAs did not provide a significant benefit in the risk for atrial fibrillation (RR = 0.81, 95% CI: 0.78–1.15, I2=51%) (Figure 1a), atrial flutter (RR=0.79, 95% CI: 0.53–1.16, I2=0%) (Figure 1b), ventricular fibrillation (RR=0.99, 95% CI: 0.48–2.04, I2=0%) (Figure 1c), ventricular tachycardia (RR=1.41, 95% CI: 0.87–2.28, I2=10%) (Figure 1d), atrial tachycardia (RR=0.63, 95% CI: 0.10–3.90, I2=24%) (Figure 2a), sinus node dysfunction (RR=0.70, 95% CI: 0.40–1.23, I2=0%) (Figure 2b), ventricular extrasystoles (RR=1.37, 95% CI: 0.56–3.30, I2=0%) (Figure 2c), second-degree atrioventricular block (RR=0.96, 95% CI: 0.52–1.74, I2=0%) (Figure 2d) or complete atrioventricular block (RR=0.78, 95% CI: 0.39–1.54, I2=38%) (Figure 2e).

Conclusions

In patients with type 2 diabetes mellitus, treatment with GLP-1RAs does not significantly affect the risk for major cardiac arrhythmias.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Meta-analysis assessing cardiovascular outcomes with febuxostat versus allopurinol for patients with gout

Background

Gout, the most common inflammatory arthritis in the USA, represents an established risk factor for cardiovascular disease and coronary artery disease mortality. In addition, patients with gout experience an increased risk for non-fatal myocardial infarction, while they might also feature increased risk for stroke. Recent real-world data also highlight the association between gout and atrial fibrillation, which inevitably augments cardiovascular burden. Allopurinol, a xanthine oxidase inhibitor, remains the uric acid-lowering treatment option of first choice, while febuxostat is prescribed, when allopurinol is contraindicated or not tolerated. Unfortunately, medication adherence among gout patients is poor, associated with age and related co-morbidities.

Purpose

We sought to determine the comparative efficacy of febuxostat versus allopurinol across surrogate cardiovascular outcomes of interest, by pooling data from the 2 dedicated cardiovascular outcome trials available so far. The motive for this analysis was the U.S. Food and Drug Administration (FDA) warning raised after the publication of the CARES trial, regarding the increased risk for cardiovascular and all-cause death with febuxostat compared to allopurinol.

Methods

We pooled data from the 2 dedicated cardiovascular outcome trials (CARES and FAST) and we assessed the following cardiovascular outcomes of interest: cardiovascular death, all-cause death, non-fatal myocardial infarction (MI), non-fatal stroke, fatal MI, fatal stroke, transient ischemic attack, hospitalization for heart failure, coronary revascularization, cerebrovascular revascularization and atrial fibrillation. Risk of bias was low across the included studies.

Results

Our analysis in a total of 12,318 patients with gout showed that febuxostat compared to allopurinol treatment does not confer significant risk reduction for any of the assessed, prespecified surrogate outcomes in a study population with significant cardiovascular co-morbidities (Figure 1). One third of patients enrolled in the FAST trial and 40% of the patients enrolled in the CARES trial had pre-existing cardiovascular disease, as depicted in Figure 2. Heterogeneity was low for the vast majority of the assessed outcomes, except for cardiovascular and all-cause death and fatal MI.

Conclusions

There is no significant difference across surrogate cardiovascular outcomes of interest between febuxostat and allopurinol in patients with gout and cardiovascular co-morbidities. Febuxostat seems to be a safe treatment alternative to allopurinol, despite initial concerns in terms of its cardiovascular safety.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Sodium-glucose co-transporter-2 inhibitors and the risk of major arrhythmias: a meta-analysis of the cardiovascular and renal outcome trials

Background

Type 2 diabetes mellitus is closely associated with cardiovascular disease and evidence already exists on its arrhythmogenic action. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) are a unique class of oral antidiabetic medications which recently attracted attention for reducing the total risk of major adverse cardiovascular events in a series of recent, large placebo-controlled randomized clinical trials (RCTs). Dapagliflozin and empagliflozin additionally seem to improve survival and outcomes in patients with heart failure with reduced ejection fraction (HFrEF), irrespective of the presence of diabetes mellitus. Whether antidiabetic treatment with sodium-glucose co-transporter inhibitors could reduce the arrhythmic burden in diabetic patients still is to be clarified.

Purpose

The purpose of the present meta-analysis was to report the impact of SGLT2i on the risk for several types of cardiac arrhythmias, pooling data from all relevant cardiovascular and renal outcome, placebo-controlled, RCTs, comparing SGLT2i to placebo.

Methods

We searched PubMed for all available cardiovascular and renal outcome RCTs utilizing SGLT2i, along with grey literature sources. We sought to determine the risk of the following arrhythmias/cardiac disorders with the use of SGLT2i versus placebo: atrial fibrillation, atrial flutter, supraventricular tachycardia, ventricular tachycardia, ventricular fibrillation, ventricular extrasystoles, sinus bradycardia, sinus node dysfunction, second degree atrioventricular block, complete atrioventricular block.

Results

We extracted relevant data from 8 trials (5 dedicated cardiovascular outcome trials, 2 dedicated renal outcome trials, 1 trial enrolling patients with HFrEF), pooling data in a total of 55,966 patients. SGLT-2i treatment compared to placebo produced a significant reduction in the risk of atrial fibrillation equal to 21% (RR=0.79, 95% CI: 0.67–0.93, I2=0%) (Figure 1). A non-significant reduction in the risk of atrial flutter equal to 9% (RR=0.91, 95% CI: 0.64–1.29, I2=0%) was also observed with SGLT2i (Figure 2). No significant effect on the rest major arrhythmias was observed.

Conclusions

Antidiabetic therapy with SGLT2i seems to hold a significant impact on antiarrhythmic burden in type 2 diabetes mellitus, reducing the risk of atrial fibrillation development.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Meta-analysis of cardiovascular outcome trials assessing the cardiovascular efficacy and safety of dipeptidyl peptidase-4 inhibitors in patients with type 2 diabetes mellitus

Background

Type 2 diabetes mellitus (T2DM) represents an independent risk factor for the development of cardiovascular disease, which accounts for half of deaths among the affected patients. Patients with T2DM experience higher incidence of vascular interventions compared to high-risk patients without T2DM or cardiovascular disease at baseline, underscoring the necessity for targeted therapeutic interventions. Dipeptidyl peptidase-4 (DPP-4) inhibitors constitute a safe treatment option with fair glycemic efficacy in T2DM whose cardiovascular efficacy has been doubted over recent years. A series of randomized controlled trials (RCTs) addressing cardiovascular outcomes with DPP-4 inhibitors have been recently published, while previous meta-analyses failed to show any cardiovascular benefit with their use in patients with T2DM.

Purpose

The purpose of our analysis was to report the impact of antidiabetic treatment with DPP-4 inhibitors on different cardiovascular efficacy outcomes.

Methods

We searched PubMed for all published RCTs assessing cardiovascular outcomes after antidiabetic treatment with DPP-4 inhibitors. We extracted data related to the following efficacy outcomes: fatal and non-fatal myocardial infarction, fatal and non-fatal stroke, hospitalization for heart failure, hospitalization for unstable angina, hospitalization for coronary revascularization and cardiovascular death.

Results

We pooled data from a total of 6 trials in a total of 52,520 patients. Antidiabetic treatment with DPP-4 inhibitors did not significantly affect any of the prespecified cardiovascular efficacy outcomes. More specifically, DPP-4 inhibitors compared to control led to a non-significant increase in the risk for fatal and non-fatal myocardial infarction (RR=1.02, 95% CI: 0.94–1.11, I2=0%), hospitalization for heart failure (RR=1.09, 95% CI: 0.92–1.29, I2=65%) and cardiovascular death (RR=1.02, 95% CI: 0.93–1.11, I2=0%), as shown in figures 1a, 1c and 1f. In addition, DPP-4 inhibitors produced a non-significant decrease in the risk for fatal and non-fatal stroke (RR=0.96, 95% CI: 0.85–1.08, I2=0%) and coronary revascularization (RR=0.99, 95% CI: 0.90–1.09, I2=0%), as depicted in figures 1b and 1e. Finally, DPP-4 inhibitors demonstrated a neutral effect on the risk for hospitalization due to unstable angina (RR=1.00, 95% CI: 0.85–1.18, I2=0%), as shown in figure 1d.

Conclusions

Antidiabetic treatment with DPP-4 inhibitors does not seem to confer any significant cardiovascular benefit for patients with T2DM.

Funding Acknowledgement

Type of funding sources: None. Figure 1

P-wave beat-to-beat morphology analysis outperforms conventional P-wave indices in detecting patients with paroxysmal atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Background

Atrial fibrillation (AF) - the most common sustained cardiac arrhythmia - while not a life-threatening condition itself, leads to an increased risk of stroke and high rates of mortality. Early detection and diagnosis of AF is a critical issue for all health stakeholders.

Purpose

The aim of this study is to compare the performance of standard P-wave indices with beat-to-beat P-wave morphological variability parameters in identifying patients with history of Paroxysmal Atrial Fibrillation (PAF).

Methods

Three-dimensional 1000Hz ECG digital recordings of 10 minutes duration were obtained from a total of 39 PAF patients and 60 healthy individuals. Following artifacts and ectopic beats removal, P‑wave morphology analysis was performed based on the dynamic application of the k‑means clustering process and main and secondary P-wave morphologies were identified. The percentage of P-waves following the main or the secondary morphology in each lead was calculated, as well as established indices such as Advanced Interatrial Block, P-wave duration, axis and area, P-wave Terminal Force in lead V1 and Orthogonal Leads Type 1, 2 or 3.

Results

9 out of 24 parameters studied, were found to be significantly different between the two groups. 7 of these indices were derived from morphology analysis and 2 from P-wave area. Logistic regression revealed that the percentage of P-waves allocated to main morphology in X axis performed better than all other indices in identifying patients with PAF history from healthy volunteers in terms of total accuracy and F1 measure.

Conclusion

P-wave beat-to-beat morphology analysis can identify PAF patients during normal sinus rhythm more efficiently than standard P-wave indices. Abstract Figure.

Acute aortic dissection type A: case series and insights on incidence, management and outcomes

BACKGROUND

Acute aortic dissection (AAD) is a life-threatening condition with high mortality rates, despite significant advances in surgical approaches. The understanding of the clinical presentation and outcomes is crucial in order to upgrade management strategies. However, epidemiological data regarding AAD occurrence are scarce in Europe, highlighting the gap of evidence in the existing guidelines.

CASE SERIES

We investigated 197 consecutive patients admitted to our institution from January 2018 to December 2019 with suspicion of type A AAD, conducting a retrospective case series. All demographic characteristics, as well as the outcomes of these patients, were recorded and further analyzed to deliver data on the epidemiology of AAD. A total of 197 patients were admitted to our hospital with a suspected AAD. Forty-one (25.9 %) patients presented with a dilated aortic lumen or with a previously repaired aortic dissection, while 28 patients (14.2 %) were diagnosed with AAD (14 patients with type A AAD, 13 with type B AAD and 1 with intramural hematoma). Among 14 patients with type A AAD, nine patients (64.0 %) were treated surgically, while the rest were managed conservatively due to futile clinical status or inability for immediate transportation to a surgical facility. The most frequent initial symptom was chest pain in 86.0 % of patients, followed by dyspnea in 42.9 %. Post-surgical mortality was 33.0 %, while all patients that were managed conservatively did not survive. D-dimers on arrival were significantly lower among patients who survived compared to those who did not.

CONCLUSION

The incidence of type A AAD in our case series was consistent with the one demonstrated in other international cohorts; however, the mortality in our patient group was higher. Our results encourage surgical treatment due to a lower in-hospital mortality rate when compared to conservative treatment. HIPPOKRATIA 2021, 25 (1):42-46.

The prognostic value of novel myocardial deformation parameters for sudden events in hypertrophic cardiomyopathy

Background

Data about the implications of two-dimensional (2D) speckle tracking myocardial deformation parameter for predicting sudden arrhythmic events in hypertrophic cardiomyopathy (HCM) are limited.

Purpose

The aim of our study was to prospectively evaluate the predictive value of novel myocardial deformation parameters with regard to 2D speckle tracking echocardiography in patients with HCM.

Methods

This was a prospective study that included HCM patients without concomitant severe valvular heart disease, without prior myocardial infarction and with sinus rhythm at index evaluation. A total of 317 patients were screened and 67 subjects were excluded. Finally, the study sample consisted of 250 patients (mean age 50.8±15.8, 67.2% male). Global longitudinal strain (GLS), left atrial (LA) strain, radial strain, circumferential strain, and mechanical dispersion of the left ventricle ((MD)-the standard deviation of time to peak negative strain in 18 left ventricular segments) were examined. The primary outcome of the study was sudden arrhythmic events including sudden cardiac death, sustained ventricular tachycardia, resuscitated cardiac arrest and appropriate impantable cardioverter defibrillator discharges.

Results

During a mean follow-up of 2.4±1.2 years, 19 patients suffered a sudden arrhythmic event. GLS, LA strain, MD and radial strain significantly predicted sudden events among our cohort. The optimal cut-off values obtained from receiver-operator characteristic curves were for GLS >−14%, for LA strain <12%, for radial strain <21% and for MD >67ms. However, only GLS >−14% and LA strain <12% displayed a significant additive predictive value on top of the European Society Of Cardiology risk score (HCMRisk-SCD) (C statistic from 0.757 to 0.831, p=0.03 including GLS >−14% in the survival model and to 0.839, p=0.009 including LA strain <12% in the model). (Table)

Conclusion

GLS and LA strain conferred a significant additional prognostic value to HCMRisc-SCD score for predicting sudden arrhythmic events in HCM patients.

Funding Acknowledgement

Type of funding source: None

Baseline adenosine plasma levels indicate differential response to adenosine test and head-up tilt test in syncopal patients

Background/Introduction

Head-up tilt table test (HUTT) and Adenosine test (ADT) can be useful in the diagnostic evaluation of syncope. Adenosine plasma (ADP) and Adenosine receptor (ADR) levels may differentiate the outcomes of HUTT and ADT but their precise role in the risk stratification of patients with syncope remains elusive.

Purpose

We sought to assess the ADP and ADR levels in patients without structural heart disease who underwent HUTT and ADT tests as part of the diagnostic workup of syncope. We specifically investigated differences in the outcomes of the HUTT and ADT tests as well as to the ADP levels during HUTT according to the baseline ADP levels.

Methods

HUTT and ADT were performed as per the standard protocols. ADT was considered positive in the event of asystole >6 seconds or heart block for >10 seconds after intravenous Adenosine 0.15 mg/kg administration in the supine position. ADP levels (ppm/Um/L) were assessed at three timepoints during the HUTT: at baseline (supine), immediately after bed tilt and, in cases of a positive HUTT, at the time of syncope. Patients were categorized in terciles of low, intermediate and high baseline ADP levels. We also assessed the A2A ADR levels of monocytes.

Results

We prospectively analyzed 106 patients (62 women, age 46.87±20.63 years). ADT was positive in 14.2% of patients and HUTT in 47.2% of patients. Females were more likely to have low ADP levels (odds ratio [OR] 2.70, 95% Confidence Interval [CI] 1.04 to 6.94, p<0.05). Patients with low baseline ADP levels showed a trend for positive ADT (OR 3.15, 95% CI 1.05 to 10.85, p=0.07), while patients with high baseline ADP levels showed a trend for negative HUTT (OR 2.35, 95% CI 0.94 to 5.90, p=0.075). Within patients with positive HUTT, those with low baseline ADP levels, showed an increase in ADP in the tilt phase (0.063 vs 0.027 ppm/Um/L, p<0.05) but not at the time of syncope (0.045 ppm/Um/L) while those with intermediate baseline ADP levels showed an increase in ADP in the tilt phase (0.16 vs 0.095 ppm/Um/L, p<0.05) which persisted during syncope (0.18 ppm/Um/L, p<0.05). Patients with high baseline ADP levels did not exhibit differences in ADP during positive HUTT. Higher baseline ADP levels were associated with smaller increases in the tilt phase (Pearson's r −0.621, p<0.001). ADR levels in patients with positive HUTT correlated positively with baseline ADP levels (Pearson's r 0.878, p<0.001).

Conclusion(s)

Baseline ADP levels may be related to the outcome of ADT and HUTT. ADP increases during HUTT except for patients with high baseline ADP. ADP and ADR levels warrant further investigation as they may characterize a subset of patients with specific responses to HUTT and may be implicated in the pathophysiology of reflex syncope.

Funding Acknowledgement

Type of funding source: None

Impact of procedural volume on complication and recurrence rate after atrial fibrillation ablation in European centers. An ESC EORP Registry: Atrial Fibrillation Long-Term

Background

Catheter ablation has emerged as an effective therapy in patients with atrial fibrillation (AF). Despite high success rates of the method, there is still heterogeneity of outcomes and complications across Europe. A center's volume of AF ablations performed per year might also play an important role in the success rate of the procedure as compared to other confounding factors which may be different among centers (such as type of AF ablated, patient selection criteria, referral bias and/or ablation strategy).

Purpose

Aim of the study was to investigate differences in clinical outcomes and complication rates among European AF ablation centers related to the volume of ablations performed annually.

Methods

Data for this analysis were extracted from the European AF Ablation Long-Term Study, a prospective registry designed to describe the clinical epidemiology of patients undergoing AF ablation. Based on 33th and 67th percentiles of number of AF ablations performed, the participating centers were classified into high volume (HV) (≥180 procedures/year), medium volume (MV) (<180 and ≥74/year) and low volume (LV) (<74/year). One-year success was defined as patient survival free from any atrial arrhythmia, from the end of the 3-month blanking period to 12 months following the ablation procedure.

Results

A total of 91 centers in 26 European countries enrolled 3368 patients. There was a significantly higher reporting of cardiovascular complications in LV centers (5.2%), especially pericarditis and cardiac perforation, while the HV and MV centers reported cardiovascular complications in 3.0 and 4.3% of cases, respectively (p=0.039). Additionally, stroke incidence after ablation was significantly higher in LV centers (0.5% of cases vs 0% in HV and MV centers, p=0.008). One-year success after AF ablation ranged from 77.8% in HV vs 70.5% in LV vs 77.3% in MV centers (p<0.001). Despite these unadjusted differences, Kaplan-Meier survival analysis based on adjusted data demonstrated, however, that there were not significant differences in complication and recurrence rates according to volume's center (p=0.328 and p=0.476 accordingly, Figure A). This result was mainly driven by a proportional increase in severity/risk of cases ablated (as evidenced by CHA2DS2-VASc score and AF type) in relation to a center's procedural volume (Figure B).

Conclusions

Low volume centers present slightly higher cardiovascular complications' and stroke incidence and a lower unadjusted success rate after AF ablation. On the other hand, adjusted overall complication and recurrence rates are non-significantly different among different volume centers, a fact reflecting inhomogeneity of patient and procedural profiles and a counterbalance between expertise and risk level among participating centers.

Funding Acknowledgement

Type of funding source: None

Early-onset and recurrent reflex syncope is associated with left ventricular diastolic filling and left atrial function properties

Background/Introduction

The effects of the left atrial and ventricular function in the pathophysiology of reflex syncope remain elusive. Head-up tilt table test (HUTT) is frequently used in the diagnostic workup of patients with syncope, but the outcomes of HUTT have not been attributed to any anatomical or functional cardiac characteristics.

Purpose

We sought to assess the effects of anatomical and functional echocardiographic features of the left atrium and the left ventricle at rest in the clinical presentation of syncope and the outcomes of HUTT.

Methods

We investigated patients with a history of syncope and symptoms suggestive of reflex syncope who underwent HUTT. Specific echocardiographic indices of left cardiac morphology and function were assessed at rest. The patients were divided into two groups, those who presented with syncopal episodes at age <35 years (group A) and those who presented with syncopal episodes at age >35 years (group B).

Results

In 119 patients (age 46.75±21.17 years, 69 women), patients in group A exhibited a higher chance for numerous (>3) syncopal episodes (odds ratio [OR] 3.4, 95% Confidence Interval [CI] 1.41 to 7.93, p<0.05). Group A showed also a trend for positive HUTT (OR 1.99, 95% CI 0.97 to 4.23, p=0.08). In patients with positive HUTT, Group A had higher E-wave velocity (0.83 vs 0.65 m/sec, p<0.05), lower A-wave velocity (0.60 vs 0.75 m/sec, p<0.05), higher E/A ratio (1.54 vs 1.00, p<0.05), higher e' wave velocity (0.16 vs 0.10 m/sec, p<0.05) and lower E/e' (5.64 vs 7.85, p<0.05). Also, patients in group A exhibited lower left atrial volumes (min 9.88 vs 16.21 ml, p<0.05, max 30.42 vs 44.89 ml, p<0.05), higher left atrial strain reservoir (40.56 vs 32.42%, p<0.05) and higher left atrial strain booster (25.94 vs 18.06%, p<0.05).

Conclusion(s)

Patients with a younger age of onset and recurrent syncopal episodes manifest smaller dimensions of the left atrium with distinct patterns of diastolic performance and better reservoir and booster function. These findings may indicate a more pronounced susceptibility of this group of patients to preload reduction, thereby triggering the mechanism of reflex syncope.

Funding Acknowledgement

Type of funding source: None

Three-dimensional volume-strain loops may reflect fibrosis in hypertrophic cardiomyopathy

Background

Combined plotting of deformation parameters against other indices [e.g. arterial pressure, left ventricular (LV) volume] might offer additional information about different diseases. Especially in hypertrophic cardiomyopathy (HCM) this approach might offer new insights into the various phenotypic and pathophysiologic features of this entity.

Purpose

Aim of this study was i) to apply strain-volume loops in HCM based on simultaneous frame-by-frame strain and volume changes' recordings acquired by means of three-dimensional (3D) speckle tracking imaging and ii) to investigate potential correlations between these loops and phenotypic features of HCM (including thickness, obstruction and fibrosis).

Methods

We included 40 HCM patients (54.1±14.3 years, 82.5% male, maximum wall thickness 19.3±4.8mm) who have consecutively undergone 3D-speckle tracking echocardiography and cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE). Values of 3D strain were plotted vs. volume for each frame to build a strain–volume loop. Peak of radial, longitudinal, and circumferential systolic strain (Rsp, Lsp, and Csp, respectively), systolic slopes of the loops (RsSl, LsSl, CsSl), and strain to end-diastolic volume (EDV) ratio (Rs/V, Ls/V, Cs/V) were computed for the analysis (panel A). Additionally, burden of fibrosis (percentage of LV mass) was defined by LGE extent (>5 standard deviations compared to nulled myocardium) in CMR slices.

Results

All HCM patients had preserved EF (60.5±5,7%), while 16 (40%) had LV outflow tract obstruction (LVOTO>30 mm Hg at rest). Mean LV mass index was 78.9±14.5 g (evaluated by 3D echocardiography). LGE was observed in 23 patients (57.5%) occupying 5.2±4.5% of LV mass. Concerning strain-volume loops the following values were recorded for radial (Rsp 30.8±9.8%, RsSl 0.4±0.13 and Rs/V 0.25±0.09), longitudinal (Lsp −9.4±3.7%, LsSl 0.12±0.06 and Ls/V 0.08±0.04) and circumferential deformation (Csp −14.2±3.5%, CsSl 0.18±0.05 and Cs/V 0.11±0.03). Among typical HCM characteristics tested (LV mass, LVOTO and LGE), only LV mass presented significant correlations with LsSl (r=−0.41, p<0.01). Interestingly, HCM patients with smaller LVMI and without LGE presented steeper and narrower (difference between systolic and diastolic strain for the same volume) longitudinal strain-volume loops compared to patients with larger LVMIs and fibrosis (panel B).

Conclusions

Strain-volume loop is an innovative application of 3D deformation imaging in HCM. According to this new non-invasive method, increase of LVMI in HCM is accompanied by less longitudinal contribution to stroke volume, whereas better systolic-diastolic coupling may exclude the presence of underlying fibrosis.

Funding Acknowledgement

Type of funding source: None

Impact of a 246 km ultra-marathon race on global and segmental longitudinal deformation of all cardiac chambers and on inter-chamber relationships

Background

It is well documented that prolonged intense exercise such as a marathon, transitorily alters cardiac function. However, the impact of ultra-endurance (UE) exercise on global and segmental longitudinal deformation of all cardiac chambers and on inter-chamber functional relationships has not yet been thoroughly investigated.

Purpose

The aim of the study was the evaluation of the acute effects of UE exercise on longitudinal deformation of all cardiac chambers and on intra-, inter- and atrioventricular functional relationships.

Methods

Echocardiographic assessment was performed the day before and at the finish line of “Spartathlon”: a 246 Km ultra-marathon. 2D speckle-tracking echocardiography was performed in all 4 chambers during the same cardiac cycle, allowing a simultaneous strain-time data display of all cardiac chambers (Figure 1). Peak global deformation values and temporal parameters adjusted for the heart rate were extracted from the derived curves, while a segmental analysis for left (LV) and right ventricle (RV) was also performed.

Results

Out of 60 participants initially screened, 27 athletes (17 male, age 45±7 years) finished the race in 33:34±1:59 hours. Both LV (−20.9±2.3 pre- to −18.8±2% post-, p=0.009) and RV global strains (−22.9±3.6 pre- to −21.2±3% post-, p=0.04) decreased post-race, even though remained within normal range for the 85% of the participants. Peak atrial strains [right (RA) and left (LA)] did not change (p=0.12 and 0.95). Basal and mid segmental strain values significantly decreased post-race, while both LV and RV apical strain values remained unaffected (p=0.899 and p=0.46, accordingly) (Figure). Concerning interchamber relationships, RV and RA strain curves were constantly larger in magnitude than those of the LV and LA, with RV/LV, LV/LA, RV/RA and RA/LA peak values' ratios remaining unchanged from pre- to post-race. Finally, although right chambers' time-to-peak values were shorter compared to the left ones, all chambers' strain curves peaked later post-race (p<0.001 for all).

Conclusions

Despite subtle changes in LV and RV strain, 4-chamber deformation values remained within normal range even after running a 246 km ultra-marathon. Following a segmental analysis, this finding could be explained for both ventricles by a preservation of apical deformation. Additionally, inter- and atrioventricular concordance was also maintained.

Figure 1

Funding Acknowledgement

Type of funding source: None

219A machine learning classification algorithm to detect patients with paroxysmal atrial fibrillation during sinus rhythm

Background

Atrial fibrillation (AF) - the most common sustained cardiac arrhythmia - while not a life-threatening condition itself, leads to an increased risk of stroke and high rates of mortality. Early detection and diagnosis of AF is a critical issue for all health stakeholders.

Purpose

The aim of this study is to identify P-wave morphology patterns encountered in patients with Paroxysmal AF (PAF) and to develop a classifier discriminating PAF patients from healthy volunteers.

Methods

Three-dimensional 1000Hz ECG signals of 5 minutes duration were obtained through the use of a Galix GBI-3S Holter monitor from a total of 68 PAF patients and 52 healthy individuals. Signal pre-processing, consisting of denoising, QRS auto-detection, and ectopic beats removal was performed and a signal window of 250ms prior to the Q-wave (Pseg) was considered for every single beat. P‑wave morphology analysis based on the dynamic application of the k‑means clustering process was performed. For those Pseg that were assigned in the largest cluster, the mean P-wave was computed. The correlation of every P-wave with the mean P-wave of the main cluster was calculated. In case that it exceeded a prespecified threshold, the P-wave was allocated to the main morphology. For the remaining P‑waves, the same approach was followed once again, and the secondary morphology was extracted (picture). The P-waves of the dominant morphology were further analyzed using wavelet transform, whereas time-domain characteristics were also extracted.

A Support Vector Machine (SVM) model was created using the Gaussian Radial Basis Function kernel and the forward feature selection wrapper approach was followed. ECGs were allocated to the training, internal validation, and testing datasets in a 3:1:1 ratio.

Results

The percentage of P-waves following the main morphology in all three leads was lower in PAF patients (91.2 ±7.3%) than in healthy subjects (96.1 ±3.5%, p = 0.02). Classification between the two groups highlighted 7 features, while the SVM classifier resulted in a balanced accuracy of 91.4 ± 0.2% (sensitivity 94.2 ± 0.3%, specificity 88.6 ± 0.1%)

Conclusion

An Artificial Intelligence based ECG Classifier can efficiently identify PAF patients during normal sinus rhythm.

Abstract Figure.

244An automated beat exclusion algorithm to improve beat-to-beat P-wave morphology analysis

Background

A manually beat-to-beat P-wave analysis has previously revealed the existence of multiple P-wave morphologies in patients with paroxysmal Atrial Fibrillation (AF) while on sinus rhythm, distinguishing them from healthy, AF free patients.

Purpose

The aim of this study was to investigate the effectiveness of an Automated Beat Exclusion algorithm (ABE) that excludes noisy or ectopic beats, replacing manual beat evaluation during beat-to-beat P-wave analysis, by assessing its effect on inter-rater variability and reproducibility.

Methods

Beat-to-beat P-wave morphology analysis was performed on 34 ten-minute ECG recordings of patients with a history of AF. Each recording was analyzed independently by two clinical experts for a total of four analysis runs; once with ABE and once again with the manual exclusion of ineligible beats. The inter-rater variability and reproducibility of the analysis with and without ABE were assessed by comparing the agreement of analysis runs with respect to secondary morphology detection, primary morphology ECG template and the percentage of both, as these aspects have been previously used to discriminate PAF patients from controls.

Results

Comparing ABE to manual exclusion in detecting secondary P-wave morphologies displayed substantial (Cohen"s k = 0.69) to almost perfect (k = 0.82) agreement. Area difference among auto and manually calculated main morphology templates was in every case <5% (p < 0.01) and the correlation coefficient was >0.99 (p < 0.01). Finally, the percentages of beats classified to the primary or secondary morphology per recording by each analysis were strongly correlated, for both main and secondary P-wave morphologies, ranging from ρ=0.756 to ρ=0.940 (picture)

Conclusion

The use of the ABE algorithm does not diminish inter-rater variability and reproducibility of the analysis. The primary and secondary P-wave morphologies produced by all analyses were similar, both in terms of their template and their frequency. Based on the results of this study, the ABE algorithm incorporated in the beat-to-beat P-wave morphology analysis drastically reduces operator workload without influencing the quality of the analysis.

Abstract Figure.

P322Understanding the multiple P-wave morphologies in paroxysmal atrial fibrillation, during sinus rhythm, using computer simulation

Background

Atrial Fibrillation (AF) is the most common atrial arrhythmia. The initiation and perpetuation of AF are related to atrial remodeling affecting the electrical and structural atrial characteristics. The beat-to-beat analysis of the P-wave morphology (PWM), during sinus rhythm (SR), revealed the existence of a secondary PWM, while the proportion of the P-waves which follow the secondary morphology is higher in patients with a history of paroxysmal AF (pAF). This observation has led to the hypothesis that the multiple PWM may be the result of a transient shift in the stimulus origin, possibly within the broader anatomical region of the sinoatrial (SA) node, and it is the atrial electrical remodeling that contributes to more frequent P-waves following a secondary morphology in patients with pAF.

Purpose

To better understand the pathophysiology of AF there is a need to link different levels of analysis, in order to interpret macroscopic observations, through a surface electrocardiogram, with changes occurring at cell and tissue level. Towards this direction, computational modeling can be used as it is a non-invasive and reproducible method of analyzing the electrical activity of the heart.

Methods

The CRN atrial model was used, and a two-dimensional geometry of the atrial architecture was considered, including the major anatomical structures, like Crista Terminalis, Pectinate Muscles and Pulmonary Veins. Using existing knowledge, the CRN model was adapted to describe the ionic properties of the atrial structures as well as the electrical remodeling occurring under pAF conditions. Several scenarios were considered related to the extent of the electrical remodeled tissue and Heart Rate (HR) values. The stimulation protocol was designed as 5 stimuli originated at a specific point within the SA node area whereas the sixth stimulus originated either at the same location or 1 mm far from the previous one. The temporal variations of the atrial activation as a result of the transient shift of the sixth stimulus origin were computed.

Results

In electrically remodeled tissue, the displacement of the excitation site within the SA node resulted in a significant increase of the differences in atrial activation compared to healthy tissue, and the greater the spatial extent of the remodeling the greater the differences in the completion of the electrophysiological processes. In addition, increased HR or HR variability led to the increase of the differences especially when electrical remodeling coexists.

Conclusions

The observed differences in atrial substrate activation can explain the increased number of P-waves that match a secondary PWM in pAF patients during SR, while a future perspective is to use PWM as a marker to estimate the electrical remodeling extent in the atrial tissue. These results underline the need to link the macroscopic findings to the suspected microscopic electrical activity in order to better understand the pathophysiology of AF.

1181 A novel insight into pathophysiology of hypertrophic cardiomyopathy using simultaneous three-dimensional volume-strain loops

Funding Acknowledgements

Supported with a scholarship by the Greek State Scholarship Foundation (IKY).

Background

Strain assessment offers a robust evaluation of myocardial mechanics and systolic function, however reporting only peak strain values in hypertrophic cardiomyopathy (HCM) may impose limitations in the conception of its complex remodeling. Therefore, combined plotting of deformation parameters against other indices [e.g. arterial pressure, left ventricular (LV) volume] might offer additional insights into the pathophysiology of the disease.

Purpose

Aim of this study was i) to apply strain-volume loops in HCM based on simultaneous frame-by-frame strain and volume changes’ recordings acquired by means of three-dimensional (3D) speckle tracking imaging and ii) to take advantage of the previous methodology to gain further insights into HCM pathophysiology.

Methods

We included 40 HCM patients (54.1 ± 14.3 years, 82.5% male, maximum wall thickness 19.3 ± 4.8mm) who have consecutively undergone 3D-speckle tracking echocardiography and cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE). Values of 3D strain were plotted vs. volume for each frame to build a strain–volume loop. Peak of radial, longitudinal, and circumferential systolic strain (Rsp, Lsp, and Csp, respectively), systolic slopes of the loops (RsSl, LsSl, CsSl), and strain to end-diastolic volume (EDV) ratio (Rs/V, Ls/V, Cs/V) were computed for the analysis (panel A). Additionally, burden of fibrosis (percentage of LV mass) was defined by LGE extent (>5 standard deviations compared to nulled myocardium) in CMR slices.

Results

All HCM patients had preserved EF (60.5 ± 5,7%), while 16 (40%) had LV outflow tract obstruction (LVOTO > 30 mm Hg at rest). Mean LV mass index was 78.9 ± 14.5 g (evaluated by 3D echocardiography). LGE was observed in 23 patients (57.5%) occupying 5.2 ± 4.5% of LV mass. Concerning strain-volume loops the following values were recorded for radial (Rsp 30.8 ± 9.8%, RsSl 0.4 ± 0.13 and Rs/V 0.25 ± 0.09), longitudinal (Lsp -9.4 ± 3.7%, LsSl 0.12 ± 0.06 and Ls/V 0.08 ± 0.04) and circumferential deformation (Csp -14.2 ± 3.5%, CsSl 0.18 ± 0.05 and Cs/V 0.11 ± 0.03). Among typical HCM characteristics tested (LV mass, LVOTO and LGE), only LV mass presented significant correlations with LsSl (r=-0.41, p < 0.01). Interestingly, HCM patients with smaller LVMI and without LGE presented steeper and narrower (difference between systolic and diastolic strain for the same volume) longitudinal strain-volume loops compared to patients with larger LVMIs and fibrosis (panel B).

Conclusions

Strain-volume loop is an innovative application of 3D deformation imaging in HCM. According to this new non-invasive method, increase of LVMI in HCM is accompanied by less longitudinal contribution to stroke volume, whereas absence of fibrosis and severe hypertrophy is accompanied by better systolic-diastolic coupling.

Abstract 1181 Figure.

P984 A head-to-head comparison between 2D and 3D segmental strain parameters in hypertrophic cardiomyopathy

Funding Acknowledgements

Supported with a scholarship by the Greek State Scholarship Foundation (IKY).

Background

Previous studies have suggested that in normal and ischemic hearts three- (3D) and two-dimensional (2D) strain values present a moderate agreement which is prone to technical considerations. However, the level of agreement between 2D and 3D-strain imaging has never been adequately addressed in hypertrophic hearts, nor has it been validated against a "ground truth". Especially in hypertrophic cardiomyopathy (HCM), the magnitude and eccentricity of hypertrophy set additional challenges in standardization and measurement of regional 3D deformation parameters.

Purpose

Aims of this study were i) to investigate the consistency between 3D and 2D regional deformation parameters in HCM and ii) to test their accuracy in identifying regional fibrosis as this is defined by late gadolinium enhancement (LGE) in cardiac magnetic resonance (CMR).

Methods

We included 40 HCM patients (54.1 ± 14.3 years, 82.5% male, maximum wall thickness 19.3 ± 4.8mm) who have consecutively undergone 2D-,3D-speckle tracking echocardiography and CMR. Segmental circumferential (SCS) and longitudinal (SLS) strain have been calculated from 2D acquisitions and 3D full volume data, where additionally radial (SRS) and area (SAS) strain have been extracted using an 18 segment left ventricle model. Accordingly, segmental fibrosis was defined by LGE in corresponding CMR slices.

Results

Out of 720 segments evaluated, 134 (19.7%) were enhanced and 95(13.2%) thickened (thickness > 12 mm). Two dimensional LS and CS analysis was feasible in 719 (99.9%) and 678 (94.2%) segments respectively, while 686 segments (95.3%) were appropriate for 3D tracking. 3D_SLS values were -7.9 ± 6.8% less negative compared to 2D_SLS values [level of agreement (LOA)(-21.1-5.4%)], while the bias for SCS values was even higher -8.5 ± 8.6 [LOA(-25.4-8.4%)]. Absolute agreement between 2D and 3D deformation imaging modalities was poor to moderate [Intra-class Correlation Coefficient (ICC)= 0.46, 95%CI (0.15-0.68), p < 0.0005 for SLS and ICC = 0.19, 95%CI(0.07-0.38), p < 0.0005 for SCS] (Panel A). Following regression analysis, regional thickness was the only segmental factor to influence the correlation between 3D and 2D_SLS [R2 = 0.504, B = 0.33, 95%CI(0.22-0.44), p < 0.0005)], without, however, being a significant regressor for the other 2D vs 3D correlations. Among deformation indices, 2D_SLS showed the best area under the curve [(AUC)=0.78, 95%CI(0.75-0.81), p < 0.0005] to detect segmental fibrosis identified by CMR LGE, with 3D_SLS, 3D_SAS and 3D_SRS showing similar AUC (0.65) and 3D_SLS presenting the highest specificity [93.1%, 95%CI(90.6-95.1)] (Panel B).

Conclusions

In HCM, 2D and 3D deformation parameters are not interchangeable, showing modest agreement. Thickness and tracking algorithm calculating assumptions seem to induce this inconsistency. Among HCM patients, 2D_SLS remains the most accurate strain parameter to detect regional fibrosis.

Abstract P984 Figure.

P4762What do atrial fibrillation ablation procedural volume differences across European centers reflect? An ESC EORP registry: atrial fibrillation long-term

Background

Data from the European Atrial Fibrillation (AF) Ablation Long-Term Registry suggest that there are significant differences in the volume of AF ablation procedures performed across different centers even in the same country. If these differences in AF ablation volume between centers reflect regional, socioeconomic, infrastructural/technical or other disparities has not been addressed till now.

Purpose

The aim of this study was to investigate patient and non-patient related differences among European AF ablation centers according to the volume of AF ablations performed.

Methods

Data for this analysis originate from the European AF Ablation Long-Term Study, a prospective registry designed to describe the clinical epidemiology of patients undergoing AF ablation. Based on 25th and 75th percentiles of AF ablation numbers performed, the participating centers were classified into high volume (HV) (≥250 procedures/year), medium volume (MV) (<250 and ≥58/year) and low volume (LV) (<58/year). Patient (demographics, comorbidities) and non-patient (center infrastructure, procedural characteristics) related differences were assessed.

Results

A total of 91 centers in 26 European countries enrolled 3368 patients. There were no significant differences concerning regional distribution, hospital/cardiology facilities or services provided among centers with the exception of electrophysiology procedures and labs which were more abundant in HV centers (p=0.02 and <0.001 respectively). HV and MV centers ablate twice more cases of long-standing persistent and persistent AF compared to LV centers, in which paroxysmal AF reaches 78.9% of all cases (Figure A). Accordingly, first AF ablation procedure was far more frequent in LV centers compared to MV and HV (85.8% vs 76.0% vs 76.1% respectively, p<0.001). Even though HV centers ablate significantly more high risk patients (CHA2DS2-VASc score ≥2 51.4% in HV vs 46.5% in MV vs 37.2% in LV, p<0.001) (Figure B) with accompanying comorbidities, applying more elaborate ablation techniques, fluoroscopy time and radiation dose were higher among patients undergoing AF ablation in LV centers (p<0.001 for all). Despite the above-mentioned dissimilarities, Kaplan-Meier survival analysis, based on adjusted data, demonstrated non-significant differences in complication rate (p=0.402) or AF recurrence rate (p=0.363) among HV, MV and LV centers.

Conclusions

Volume of AF ablations in a center is not correlated with regional or infrastructural characteristics. The higher volume in HV centers consists mainly by more long-term persistent AF and higher risk patients, suggesting that differences in volume reflect differences in experience and personnel's commitment towards AF ablation.

P4364A direct comparison between 2D and 4D deformation imaging in hypertrophic hearts. An agreement of disagreement

Background

Previous studies have directly compared 2-dimensional (2D) and 4-dimensional (4D) deformation imaging in normal and ischemic hearts suggesting a moderate agreement prone to technical considerations. However, the level of agreement between 2D and 4D-strain imaging has never been adequately addressed in hypertrophic hearts, nor has it been validated against a “ground truth”.

Purpose

We aimed at directly comparing 4D and 2D global and regional deformation parameters and depict which may best reflect underlying segmental fibrosis in hypertrophic cardiomyopathy (HCM), as defined by late gadolinium enhancement (LGE) in cardiac magnetic resonance (CMR).

Methods

We included 40 HCM patients (54.1±14.3 years, 82.5% male, maximum wall thickness 19.3±4.8mm) who have consecutively undergone 2D-,4D-speckle tracking echocardiography and CMR. Global and segmental circumferential (CS) and longitudinal (LS) strain have been calculated from 2D acquisitions and 4D full volume data, where additionally radial (RS) and area (AS) strain have been extracted using an 18 segment left ventricle model. Accordingly, segmental fibrosis was defined by LGE in corresponding CMR slices.

Results

Deformation parameters (2D and 4D, global and regional) presented overall poor to moderate agreement (Figure A+B) with regional 4D_LS and 4D_CS values being constantly less negative compared to 2D derivatives (−7.29±6.94% and −8.53±8.8% accordingly). In regional analysis, 720 segments were evaluated of which 134 (19.7%) were enhanced and 95 of them thickened (68.8%) (thickness>12 mm), with segments presenting both characteristics showing the greatest impairment both in 2D and 4D strain values. Among segmental deformation indices, 2D_SLS showed the best area under the curve [(AUC)=0.78, 95% CI (0.75–0.81), p<0.0005] to detect segmental fibrosis, with 2D_SCS and all 4D deformation indices presenting significantly lower AUC (Figure C).

Conclusions

In HCM, 2D and 4D deformation parameters are not interchangeable, showing modest agreement. Thickness and tracking algorithm calculating assumptions seem to induce this variability. Nevertheless, among HCM patients 2D_SLS remains the best strain parameter for tissue characterization and fibrosis detection.

Acknowledgement/Funding

Supported with a scholarship by the Greek State Scholarship Foundation (IKY).

P6573Adenosine plasma levels may determine tilt table test outcome in syncopal patients with prodromal symptoms

Background/Introduction

Head-up tilt table test (HUTT) and Adenosine test (ADT) are tools frequently used in the diagnostic workup of syncope. It has been suggested that patient responses to HUTT and ADT can be related to the plasma levels of Adenosine (ADPL) and Adenosine receptors (ADR). However, the exact type of association and the role of (ADPL) and ADR levels in the risk stratification and management of patients with syncope has not yet been clarified.

Purpose

We sought to assess the ADPL and ADR levels in patients without structural heart disease who underwent HUTT and ADT tests as part of the diagnostic workup of syncope. We specifically investigated differences with regards to the presence of a history of prodromal symptoms.

Methods

HUTT and ADT were performed as per the standard protocols. ADT was considered positive in the event of asystole >6 seconds or heart block for >10 seconds after intravenous Adenosine administration in a supine position at a dose of 0.15 mg/kg. ADPL were assessed at three timepoints during the HUTT: in the supine position, immediately after bed tilt and, in cases of a positive test, at the time of syncope. Furthermore, we assessed the A2A ADR of monocytes in the study patients.

Results

We prospectively analyzed 77 patients (48 women, age 47.05±21.10 years). ADT was positive in 16.7% of patients and HUTT in 49.4% of patients. ADPL in the supine position did not differ between patients with negative vs. positive ADT but showed a significant correlation with the body mass index (p=0.002). There was a trend for reduced ADPL at the tilt phase in patients with positive HUTT (0.32±0.89 vs. 0.42±0.77 ppm/Um/L, p=0.09). Of all patients, 60 (77.9%, 41 women, age 46.80±21.83 years) had reported a history of prodromal symptoms at syncope. In the subset of patients with prodromal symptoms, the ADL at the tilt phase were lower in patients with positive vs. negative HUTT (0.15±0.23 vs. 0.51±0.89, p<0.05). ADR did not differ among groups but showed a significant correlation with the ADL during syncope in patients with prodromal symptoms (p<0.05).

Conclusion(s)

Patients with prodromal symptoms and a positive HUTT demonstrate reduced ADPL at the tilt phase of HUTT preceding syncope. In these patients, ADPL in syncope correlate with the ADR. Adenosine plasma levels and receptors warrant further investigation and may predict the response to HUTT thereby contributing to the diagnostic evaluation and risk stratification of patients with syncope.

P1028Impact of atrial fibrillation ablation procedural volume on complication and recurrence rate across European centers. An ESC EORP registry: atrial fibrillation long-term

Background

Catheter ablation has emerged as an effective therapy in patients with symptomatic and drug refractory atrial fibrillation (AF). Despite high success rates of the method, there is still heterogeneity of outcomes and complication rate across Europe. The impact of the annual procedural volume per center on success and complication rate of AF ablation, based on real-life data, has not been addressed till now.

Purpose

The aim of the study was to investigate if center AF ablation volume might be associated with one-year success or complication rate after the procedure.

Methods

Data for this analysis were extracted from the European AF Ablation Long-Term Study, a prospective registry designed to describe the clinical epidemiology of patients undergoing AF ablation. Based on 25th and 75th percentiles of AF ablation numbers performed, the participating centers were classified into high volume (HV) (≥250 procedures/year), medium volume (MV) (<250 and ≥58/year) and low volume (LV) (<58/year). One-year success was defined as patient survival free from any atrial arrhythmia, from the end of the 3-month blanking period to 12 months following the ablation procedure.

Results

A total of 91 centers in 26 European countries enrolled 3368 patients. There was a significantly higher reporting of cardiovascular complications in LV centers (5.2%), especially pericarditis (0.6%) and cardiac perforation (1.4%), while the HV and MV centers reported cardiovascular complications in 3.0 and 4.3% of cases, respectively (p=0.039). Additionally, stroke incidence after ablation was significantly higher in LV centers (0.5% of cases vs 0% in HV and MV centers, p=0.008). Kaplan-Meier survival analysis based on adjusted data of all complications demonstrated, however, that there was not a significant difference in complication rate according to volume's center (p=0.402, Figure A). One-year success after AF ablation ranged from 77.8% in HV vs 70.5% in LV vs 77.3% in MV centers (p<0.001). Nonetheless, adjusted recurrence rate was not significantly different among centers (p=0.363, Figure B), a result driven by differences both in ablation technical characteristics and risk/severity of cases ablated in different volume centers.

Conclusions

Despite the notion that “the higher, the better”, our results suggest that AF ablation is a safe procedure with high success rates in all European centers, independent of the AF ablation procedural volume. Differences in patients and procedural characteristics may justify the equality of complication and recurrence rate among centers, since expertise level counterbalances the risk of each case.

P1584The prognostic significance of the blood pressure-pulse wave velocity association for cardiovascular outcomes and mortality in hemodialysis patients

Introduction and purpose

Hemodialysis patients have premature arterial stiffness, and the relationship between pulse wave velocity (PWV) and blood pressure (BP) may be different than in other hypertensives. Previous studies showed that when BP decrease is accompanied by PWV decrease the survival is improved. The aim of this study is to examine the prognostic significance of BP sensitivity of PWV for major cardiovascular outcomes and all-cause mortality in hemodialysis patients.

Methods

This is a prospective cohort study including 242 hemodialysis patients [age, 62.6±14.2 years; female, 91 (37.6%); hemodialysis vintage, 41.53±43.46]. All subjects underwent 48-hour-ABPM with Mobil-O-Graph-NG and followed-up for 33.17±19.68 months. The within-individual MBP-PWV association (MBP, dependent and PWV independent variable) was evaluated using the beta-coefficient value from simple linear regression analysis for each patient. The primary end-point was first occurrence of all-cause death, non-fatal myocardial infarction or non-fatal stroke. Secondary end-points were: (i) all-cause mortality; (ii) cardiovascular mortality; (iii) a combination of cardiovascular events.

Results

Patients who experienced the primary end-point during follow-up had significantly lower beta-coefficient levels (primary end-point: 19.877±3.975 vs 18.483±3.550, p=0.008). Higher quartiles of beta-coefficients (indicating dependency of PWV on MBP) were associated with higher cumulative freedom from the primary end-point (50.8%, 60.0%, 70.0% and 80.3% for quartiles 1 to 4 respectively; logrank-p=0.001), higher overall survival (60.7%, 61.7%, 73.3%, 86.9%; logrank-p=0.002) and higher cardiovascular survival (78.7%, 75.0%, 81.7%, 91.8% for quartiles 1 to 4; logrank-p=0.044). The future risk for the primary end-point, all-cause and cardiovascular mortality and the combined outcome was progressively increasing for lower quartiles of beta-coefficients (HR for all-cause mortality 3.395; 95% CI: 1.524–7.563, p=0.003 for quartile 1 vs quartile 4). Age (OR: 1.046, 95% CI: 1.016–1.077 per year increase, p=0.003) and 48h heart rate (OR: 0.949, 95% CI: 0.916–0.982 per bpm increase, p=0.003) were independently associated with weaker relationship between 48h-MBP and 48h-PWV.

Conclusions

Lower within-individual MBP-PWV association, based on AMBP recordings, is associated with higher risk of death and cardiovascular events in hemodialysis. These findings support that BP-independent arterial stiffness may be the underlying factor for adverse outcomes in these individuals.

P2640The effect of dry-weight reduction guided by lung ultrasound on ambulatory aortic blood pressure and arterial stiffness parameters in hemodialysis patients

Introduction and purpose

Arterial stiffness and aortic blood pressure (BP) augmentation are significantly increased in hemodialysis patients. Recent studies suggest that the prognostic significance of ambulatory recordings of arterial stiffness is high in hemodialysis. This study examines for the first time the effect of dry weight reduction with a standardized lung-ultrasound-guided strategy on ambulatory aortic BP and arterial stiffness parameters in hypertensive hemodialysis patients.

Methods

A total 71 hemodialysis patients with hypertension (mean home BP ≥135/85 mmHg), that were clinically euvolemic, were included in this single-blind randomized clinical trial. Patients were randomized in a 1:1 ratio in the active group (n=35), following a strategy for dry-weight reduction guided by the total number of US-B lines (US-B lines score) prior to a mid-week dialysis session and the control group (n=), following standard-of-care treatment. All patients underwent 48-hour ABPM with the Mobil-O-Graph monitor (IEM, Stolberg, Germany) and PWV measurement in office with SphygmoCor (ArtCor, Sydney, Australia) at baseline and after 8-weeks.

Results

Overall, the US-B lines change during follow-up were −5.3±12.5 in active versus +2.2±7.6 in control group (p<0.001), which corresponded to dry-weight changes of −0.71±1.39 versus +0.51±0.98 kg (p<0.001). The change in 48-hour cSBP was significantly greater in the active group (−6.30±8.90 vs −0.50±12.46, p=0.027); the relevant cDBP fall was marginally greater (−3.85±6.61 vs −0.63±8.36, p=0.077) in the active group. 48-hour cPP (41.51±9.63 vs 39.06±9.61 mmHg, p=0.004) and 48-hour PWV (9.30±2.00 vs 9.08±2.04 m/sec, p=0.032) were significantly reduced from baseline to study-end in the active group but remained unchanged in controls. In contrast, 48-hour AIx and AIx(75) did not change between baseline and study-end in both groups; changes in AIx(75) were similar in the two groups (−0.97±3.51 vs −0.36±4.25, p=0.517). PWV measured in office was decreased from baseline to study-end in the active (10.07±2.66 vs 9.79±2.81, p=0.038) but not in the control group.

Conclusions

A lung-ultrasound-guided strategy for dry-weight reduction reduces ambulatory aortic BP and ambulatory or office PWV, but not ambulatory AIx(75). These results suggest that dry-weight reduction can primarily reduce aortic BP levels and large arteries stiffness but not wave reflections from the periphery.

4308Lung ultrasound guided dry-weight probing reduces left and right atrial dimensions and left ventricular filling pressures in hemodialysis patients with hypertension

Introduction and purpose

Left ventricular hypertrophy and dysfunction is tightly associated with adverse outcome in hemodialysis. Hypertension and increased preload due to hypervolemia are major factors for these cardiac anomalies in hemodialysis. This study examined the effect of lung-ultrasound-guided dry-weight reduction on echocardiographic indices of left and right cardiac size, systolic and diastolic function in hypertensive hemodialysis patients.

Methods

This pilot, single-blind trial randomised 71 clinically euvolemic hypertensive hemodialysis patients in an active group (n=35), following a strategy for dry-weight reduction guided by the total number of US-B lines (US-B lines score) prior to a mid-week dialysis session, and a control group (n=36), following standard-of-care treatment. Among others, patients underwent two-dimensional and tissue-Doppler echocardiographic (TDI) at baseline and after 8-weeks.

Results

Overall, 19 (54.3%) patients in the active and 5 (13.9%) in the control group had UF intensification (p<0.001) during follow-up (US-B lines 5.3±12.5 vs +2.2±7.6, p<0.001, dry-weight: −0.71±1.39 vs +0.51±0.98 kg, p<0.001). Inferior vena cava diameter was reduced to a greater extend in the active compared to control group (−0.43±4.00 vs 0.71±4.82, p=0.033) at study-end. Reductions in LA and RA sizing parameters were greater in the active group (LA Surface: −1.09±4.61 vs 0.93±3.06 cm2, p=0.034; RA surface: −1.56±6.17 vs 0.47±2.31, p=0.024; LAVi: −2.43±13.14 vs 2.95±9.42 ml/m2, p=0.052). Reductions in LV end-diastolic diameter and volume were marginally greater in the active group. LV filling pressures significantly decreased in the active compared to the control group (E/e' LV: −0.38±3.14 vs 1.36±3.54, p=0.034; DT: 35.43±85.25 vs −18.44±50.69, p=0.002). Systolic function indices were unchanged in both groups. In multivariate analysis, US-B lines reduction was a powerful predictor (OR: 4.542, 95% CI: 1.266–16.292, p=0.020) of E/e' LV ratio decrease, among various factors examined.

Conclusions

A lung-ultrasound-guided strategy for dry-weight reduction can effectively reduce cardiac chambers dimensions and LV filling pressures without changing systolic performance during an 8-week follow-up in hypertensive hemodialysis patients.

Diagnosis of cardiac amyloidosis: a systematic review on the role of imaging and biomarkers

BACKGROUND

Cardiac Amyloidosis (CA) pertains to the cardiac involvement of a group of diseases, in which misfolded proteins deposit in tissues and cause progressive organ damage. The vast majority of CA cases are caused by light chain amyloidosis (AL) and transthyretin amyloidosis (ATTR). The increased awareness of these diseases has led to an increment of newly diagnosed cases each year.

METHODS

We performed multiple searches on MEDLINE, EMBASE and the Cochrane Database of Systematic Reviews. Several search terms were used, such as "cardiac amyloidosis", "diagnostic modalities cardiac amyloidosis" and "staging cardiac amyloidosis". Emphasis was given on original articles describing novel diagnostic and staging approaches to the disease.

RESULTS

Imaging techniques are indispensable to diagnosing CA. Novel ultrasonographic techniques boast high sensitivity and specificity for the disease. Nuclear imaging has repeatedly proved its worth in the diagnostic procedure, with efforts now focusing on standardization and quantification of amyloid load. Because the latter would be invaluable for any staging system, those spearheading research in magnetic resonance imaging of the disease are also trying to come up with accurate tools to quantify amyloid burden. Staging tools are currently being developed and validated for ATTR CA, in the spirit of the acclaimed Mayo Staging System for AL.

CONCLUSION

Cardiac involvement confers significant morbidity and mortality in all types of amyloidosis. Great effort is made to reduce the time to diagnosis, as treatment in the initial stages of the disease is tied to better prognosis. The results of these efforts are highly sensitive and specific diagnostic modalities that are also reasonably cost effective.

Arterial adaptations in athletes of dynamic and static sports disciplines - a pilot study

BACKGROUND

Structural and functional arterial adaptations with regard to the type and level of training in young athletes are understudied. Our research aimed at evaluating them in two types of exercise (dynamic and static) and two levels of engagement (high and recreational).

METHODS

A total of 76 volunteers formed five groups. Group A included 17 high-level dynamic sports athletes 30·9 ± 6·4 years old, group B 14 recreational ones aged 28·7 ± 6·2 years, group C 15 high-level static sports athletes 26·4 ± 3·9 years old and group D 16 recreational ones, aged 25·8 ± 4·8 years. Fourteen sedentary men 30 ± 3·8 years old formed control group E. Structural indices of left cardiac chambers and thoracic aorta were echographically obtained, as well as common carotid intima-media thickness (cIMT). Furthermore, applanation tonometry was conducted, at rest and during a handgrip strength test, for the acquisition of central arterial pressure parameters, carotid-femoral pulse wave velocity (cfPWV) and total arterial compliance (C_τ ).

RESULTS

No significant differences in structural arterial markers were observed. However, group A obtained the highest handgrip central systolic pressure values (13·1% compared to group D, P<0·05). Resting cfPWV was lower in group B by 13·8% (P<0·05) than C and by 16·7% (P<0·01) than E, whereas C_τ was higher in group Β by 33·3% than C (P<0·05) and by 40·9% than E (P<0·01).

CONCLUSION

Functional arterial exercise-induced adaptations become apparent at an early age, without being in conjunction with structural ones. Recreational dynamic exercise results in the most favourable arterial characteristics.