Stress Echocardiography in Italian Echocardiographic Laboratories: A Survey of the Italian Society of Echocardiography and Cardiovascular Imaging

Background

The Italian Society of Echography and Cardiovascular Imaging (SIECVI) conducted a national survey to understand the volumes of activity, modalities and stressors used during stress echocardiography (SE) in Italy.

Methods

We analyzed echocardiography laboratory activities over a month (November 2022). Data were retrieved through an electronic survey based on a structured questionnaire, uploaded on the SIECVI website.

Results

Data were obtained from 228 echocardiographic laboratories, and SE examinations were performed in 179 centers (80.6%): 87 centers (47.5%) were in the northern regions of Italy, 33 centers (18.4%) were in the central regions, and 61 (34.1%) in the southern regions. We annotated a total of 4057 SE. We divided the SE centers into three groups, according to the numbers of SE performed: <10 SE (low-volume activity, 40 centers), between 10 and 39 SE (moderate volume activity, 102 centers) and ≥40 SE (high volume activity, 37 centers). Dipyridamole was used in 139 centers (77.6%); exercise in 120 centers (67.0%); dobutamine in 153 centers (85.4%); pacing in 37 centers (21.1%); and adenosine in 7 centers (4.0%). We found a significant difference between the stressors used and volume of activity of the centers, with a progressive increase in the prevalence of number of stressors from low to high volume activity (P = 0.033). The traditional evaluation of regional wall motion of the left ventricle was performed in all centers, with combined assessment of coronary flow velocity reserve (CFVR) in 90 centers (50.3%): there was a significant difference in the centers with different volume of SE activity: the incidence of analysis of CFVR was significantly higher in high volume centers compared to low - moderate - volume (32.5%, 41.0% and 73.0%, respectively, P < 0.001). The lung ultrasound (LUS) was assessed in 67 centers (37.4%). Furthermore for LUS, we found a significant difference in the centers with different volume of SE activity: significantly higher in high volume centers compared to low - moderate - volume (25.0%, 35.3% and 56.8%, respectively, P < 0.001).

Conclusions

This nationwide survey demonstrated that SE was significantly widespread and practiced throughout Italy. In addition to the traditional indication to coronary artery disease based on regional wall motion analysis, other indications are emerging with an increase in the use of LUS and CFVR, especially in high-volume centers.

Prognostic value of cardiopulmonary exercise testing in a European cohort with cardiovascular risk factors absent of a cardiovascular disease diagnosis

INTRODUCTION

Cardiorespiratory fitness (CRF) is now considered a vital sign. Cardiopulmonary exercise testing (CPET) is the gold-standard assessment of CRF; peak oxygen consumption (VO₂) and the minute ventilation/carbon dioxide production (VE/VCO₂) slope are considered primary CPET measures of CRF. More work is needed to determine the role of this exercise assessment in the primary care setting.

METHODS

695 subjects (mean age: 62 ± 13 years, body mass index: 28.9 ± 5.3 kg/m², 375 female and 320 male) underwent CPET using a cycle ergometer. 95% of the cohort had one or more major cardiovascular risk factor (i.e., obesity, smoking, dyslipidemia, hypertension, diabetes); no subject was diagnosed with cardiovascular disease (CVD) at the time of CPET. Subjects were tracked for the composite endpoint of cardiovascular mortality or hospital admission.

RESULTS

Mean peak VO₂, VE/VCO₂ slope and peak respiratory exchange ratio were 17.8 ± 5.8 mlO₂•kg^-1•min^-1, 26.7 ± 4.1, and 1.18 ± 0.13, respectively. There were 42 composite events during the 64 ± 18 month tracking period. Both peak VO₂ (Chi-square 16.3, p < 0.001) and the VE/VCO₂ slope (Chi-square 14.9, p < 0.001) were significant univariate predictors of the composite endpoint. The VE/VCO₂ slope added significant predictive value to peak VO₂ and was retained in the multivariate regression (residual Chi-square 7.0, p = 0.008).

DISCUSSION

These results support the prognostic value of CPET prior to a CVD diagnosis. The prognostic value of the VE/VCO₂ slope, not commonly the focus of CPET trials in patients with one or more major cardiovascular risk factors but without a confirmed CVD diagnosis, is a particularly novel finding in the current study.

Organization and Activity of Italian Echocardiographic Laboratories: A Survey of the Italian Society of Echocardiography and Cardiovascular Imaging

Background

The Italian Society of Echocardiography and Cardiovascular Imaging (SIECVI) conducted a national survey to understand better how different echocardiographic modalities are used and accessed in Italy.

Methods

We analyzed echocardiography laboratory activities over a month (November 2022). Data were retrieved via an electronic survey based on a structured questionnaire, uploaded on the SIECVI website.

Results

Data were obtained from 228 echocardiographic laboratories: 112 centers (49%) in the northern, 43 centers (19%) in the central, and 73 (32%) in the southern regions. During the month of observation, we collected 101,050 transthoracic echocardiography (TTE) examinations performed in all centers. As concern other modalities there were performed 5497 transesophageal echocardiography (TEE) examinations in 161/228 centers (71%); 4057 stress echocardiography (SE) examinations in 179/228 centers (79%); and examinations with ultrasound contrast agents (UCAs) in 151/228 centers (66%). We did not find significant regional variations between the different modalities. The usage of picture archiving and communication system (PACS) was significantly higher in the northern (84%) versus central (49%) and southern (45%) centers (P < 0.001). Lung ultrasound (LUS) was performed in 154 centers (66%), without difference between cardiology and noncardiology centers. The evaluation of left ventricular (LV) ejection fraction was evaluated mainly using the qualitative method in 223 centers (94%), occasionally with the Simpson method in 193 centers (85%), and with selective use of the three-dimensional (3D) method in only 23 centers (10%). 3D TTE was present in 137 centers (70%), and 3D TEE in all centers where TEE was done (71%). The assessment of LV diastolic function was done routinely in 80% of the centers. Right ventricular function was evaluated using tricuspid annular plane systolic excursion in all centers, using tricuspid valve annular systolic velocity by tissue Doppler imaging in 53% of the centers, and using fractional area change in 33% of the centers. When we divided into cardiology (179, 78%) and noncardiology (49, 22%) centers, we found significant differences in the SE (93% vs. 26%, P < 0.001), TEE (85% vs. 18%), UCA (67% vs. 43%, P < 0001), and STE (87% vs. 20%, P < 0.001). The incidence of LUS evaluation was similar between the cardiology and noncardiology centers (69% vs. 61%, P = NS).

Conclusions

This nationwide survey demonstrated that digital infrastructures and advanced echocardiography modalities, such as 3D and STE, are widely available in Italy with a notable diffuse uptake of LUS in the core TTE examination, a suboptimal diffusion of PACS recording, and conservative use of UCA, 3D, and strain. There are significant differences between northern and central-southern regions and echocardiographic laboratories that pertain to the cardiac unit. This inhomogeneous distribution of technology represents one of the main issues that must be solved to standardize the practice of echocardiography.

P377 CHALLENGING RISK STRATIFICATION IN BRUGADA SYNDROME: A CASE OF VENTRICULAR TACHYCARDIA IN A LOW–RISK PATIENT

A 22–year–old healthy athlete was referred to our hospital for electrocardiographic findings consistent with intermittent type–1 Brugada pattern. A routine electrocardiogram (ECG) performed during a check–up showed sinus rhythm, normal PR interval and QRS duration, rSR’ with a coved type ST–segment elevation in V2 lead (Figure 1).The patients denied history of syncope or palpitations and his family history did not show sudden cardiac death or Brugada syndrome (BrS). Transthoracic echocardiography was normal and a 12–lead Holter monitoring revealed the intermittence of the type–1 Brugada pattern. The patient was hospitalized for further investigation. On admission, ECG showed a type–2 Brugada pattern; therefore, Ajmaline challenge test (1 mg/kg injection in 10 minutes) was performed and resulted positive. Subsequently, the patient underwent an electrophysiological study (EPS) which was negative for induction of sustained arrhythmias. The protocol adopted consisted of double extrastimuli programmed electrical stimulation until refractoriness (drive 600/220 ms and 400/210 ms), at double sites (right ventricle apex and right ventricular outflow tract). Furthermore a genetic test was performed using next–generation sequencing, showing a heterozygous mutation in the SCN5A gene, encoding for sodium channel alpha subunit (variant c.5363delA), not previously described in the literature. Since the low arrhythmic risk, the patient was implanted with a loop recorder (ILR, Medtronic Reveal LINQ), entering a program of home monitoring. After a 15–months follow–up, an episode of ventricular polymorphic tachycardia lasting 2 minutes and 11 seconds, associated with lightheadedness and palpitations, was detected by the remote monitoring (Figure 2). The patient was therefore hospitalized. During the in–hospital stay a cardiac magnetic resonance was performed to exclude other underlying diseases, identifying an enlarged right ventricle (EDVi 114 ml/m2) and abnormal free wall motion (Figure 3), thus reaching one major criteria of arrhythmogenic cardiomyopathy (however not sufficient for the diagnosis). The patient was then implanted with a subcutaneous implantable cardiac defibrillator (Boston Scientific EMBLEM MRI S–ICD). We presented a case of complex arrhythmic risk stratification in a possible overlap of an arrhythmogenic cardiomyopathy and a Brugada Syndrome in a young athlete who experienced a sustained ventricular tachycardia during loop–recorder monitoring.

P35 A RARE CASE OF VENTRICULAR ARRHYTHMIA STORM AND COMPLETE ATRIOVENTRICULAR BLOCK IN A PATIENT WITH BECKER MUSCULAR DYSTROPHY

A 68 year–old male presented to the Emergency Department of our Institute with palpitations for the last 20 minutes. The patient suffered from Becker’s muscular dystrophy (BMD) with hypotonic tetraparesis and dilated cardiomyopathy with moderate left ventricular dysfunction. The patient had also arterial hypertension and a previous ischemic stroke treated with thrombolysis and subsequently with warfarin. On the admission, the patient was alert, blood pressure was 90/60 mmHg and heart rate 180 bpm. An ECG (Fig. 1) showed regular, wide–complex tachycardia (QRS duration of 240 msec) with right branch block morphology with left axial deviation. A bolus of amiodarone 200 mg ev was administered without efficacy followed by a bolus of lidocaine 50 mg. The patient developed symptomatic hypotension, so external electrical cardioversion was performed with a single DC shock at 200J, effective in restoring sinus rhythm. Amiodarone and beta blocker therapy was started. On laboratory tests, the main values were normal, including the ultrasensitive troponin hs–cTnI. Echocardiography showed a mildly dilated left ventricle with diffuse hypokinesia conditioning severe reduction of systolic function (FE 35%) (Fig. 2). On subsequent telemetric ECG monitoring, no recurrences of sustained ventricular tachycardia (VT) were recorded, but it was observed an episode of complete atrioventricular (AV) block conditioning a symptomatic 9.5–second asystole, treated with atropine. Then the patient underwent CRT–D implantation in secondary prevention. The day after the procedure, an arrhythmic storm occurred and was effectively treated with multiple attempts of antitachycardia pacing and device shock. In the following days, the patient continued to present with episodes of VT despite antiarrhythmic drugs. Hence, an endo–epicardial ablation of the arrhythmic substrate was evaluated in Heart team. In view of an intubation and the high anesthesiological risk, it was indicated to continue the optimized medical therapy. Mexiletine 200 mg tid was added to metoprolol 100 mg bid and amiodarone 200 mg od. In the following days, no arrhythmic recurrences were recorded on continuous ECG monitoring. The patient was discharged from the hospital asymptomatic and with no sign of heart failure. At 2 years of follow–up, the patient remained asymptomatic, with no arrhythmic events recorded by the device and in the absence of any adverse effects caused by mexiletine.

Prognostic significance of right ventricle to pulmonary artery coupling in patients with mitral regurgitation treated with the MitraClip system

OBJECTIVES

To evaluate the prognostic impact of baseline tricuspid annular plane systolic excursion/pulmonary artery systolic pressure (TAPSE/PASP) ratio, as an expression of the right ventricle-pulmonary artery (RV-PA) coupling, in patients with mitral regurgitation (MR) treated with the MitraClip.

BACKGROUND

Impaired RV to PA coupling is considered a marker of RV dysfunction.

METHODS

From February 2016 to February 2020, a total of 165 patients were evaluated and stratified in two groups according to a prespecified value of TAPSE/PASP ratio ≤ 0.36.

RESULTS

The median patients' age was 79 (men: 62.4%). Sixty-three patients (38.1%) presented TAPSE/PASP ≤ 0.36 and were then compared with patients with TAPSE/PASP > 0.36. Functional MR etiology was more frequent in TAPSE/PASP ≤ 0.36 (71.4%; p = 0.046). Acute technical success was achieved in 92.7% of the population, without any significant difference between the two groups of study and with sustained results at 30-day (device success: 85.5%; procedural success: 84.8%). On multivariate Cox regression analysis, after correction for body mass index, chronic kidney disease and left ventricle ejection fraction ≥30% but <50%, TAPSE/PASP ≤ 0.36 remained a sustained predictor of mortality and hospitalization for heart failure at one year after MitraClip (hazard ratio: 3.87; 95% confidence interval: 1.83-8.22; p ≤ 0.001). Kaplan-Meier all-cause mortality and heart failure hospitalization rates at one year were consequently higher in patients with TAPSE/PASP ≤ 0.36 (39.4% vs. 14.8%; log-rank p ≤ 0.001).

CONCLUSION

Baseline TAPSE/PASP ratio seems independently associated with all-cause mortality and heart failure hospitalization after MitraClip both in functional and degenerative MR.

P6315Effects of chronic heart failure unconventional therapies on endothelial function

Introduction

Endothelial Dysfunction (ED) of peripheral arteries in Chronic Heart Failure (CHF) subjects has been demonstrated.

Purpose

We assessed endothelial function in subjects undergoing unconventional treatments for CHF, namely Heart Transplantation (HTX), continuous-flow Left Ventricular Assist Device implantation (LVAD), and repeated levosimendan infusions (r-LEVO).

Methods

Twenty HTX recipients (median time from HTX 21 months), 20 patients supported with LVAD (median time from implant 39 months), and 20 patients receiving monthly Levosimendan infusions (median time on treatment 28 months) were enrolled and compared to a group of 20 healthy subjects. ED was evaluated with ultrasound assessment of the diameter before and after ischemic stress at the brachial artery level. The difference between the two diameters normalized for the baseline value (Flow Mediated Dilation – FMD) has been used for the analysis. All the patients were stable at the time of FMD assessment, with those on r-LEVO being evaluated prior to infusion.

Results

FMD was significantly lower in HTX and LVAD groups with respect to controls (9.8±7.4, 9.3±5.7, and 15.6±6.4% respectively, p=0.01), but not in r-LEVO group (12.5±6.9%).

When patients were analyzed according to time from the operation or on treatment, (< versus > of the median value), no differences were seen in HTX and r-LEVO group, while in LVAD group FMD was borderline significantly higher in patients with longer follow-up (8.4±6.4% versus 10.2±5.2%, p=0.05).

Conclusions

Based on this preliminary data we can inference the following: 1- FMD is abnormal in HTX recipients, despite their good functional status, probably due to factors unrelated to CHF (e.g. hypertension, renal insufficiency, denervation, and drug effects); 2- LVAD patients also show ED, with possible better adaptation in very long-term survivors; 3- Near-normal FMD values in CHF patients who remain stable with r-LEVO suggest that pulsed treatment may obtain favorable effects at peripheral level, persisting after clearance of the drug and its metabolites.

Acknowledgement/Funding

None