Arrhythmic Storm Research Articles

P12 SUBCUTANEOUS IMPLANTABLE CARDIOVERTER–DEFIBRILLATOR AFTER TRANSVENOUS LEAD EXTRACTION: SAFETY, EFFICACY AND OUTCOME

Abstract Background Subcutaneous implantable cardioverter defibrillator (S–ICD) is a suitable alternative for trans–venous–ICD (TV–ICD) patients underwent transvenous lead extraction (TLE) for any reason, but limited data are available about outcome of s–ICD patients implanted after TLE. Methods Thirty–six consecutive patients underwent TLE of TV–ICD and subsequent S–ICD implantation in our center were included in this prospective single–center observational study (72.2% male, median age 52 years–old). Results During a median follow-up of 31 months, 3 patients (8.3%) experienced appropriate therapy and 7 patients (19.4%) experienced complications including innapropriate therapy (IAT) (n = 4; 11.1%), pulse generator decubitus with no evidence of infection (n = 2; 5.5%) and ineffective therapy (n = 1; 2.7%). Reasons of IAT were: T–wave oversensing in one patient and extracardiac signals in the remaining 3 patients. Of note, 2 patients who experienced IAT had a left–ventricular assist device (LVAD) for refractory heart failure (HF). Premature device explantation and TV–ICD re–implantation occurred in 4 patients (11%) for pulse generator decubitus despite surgical pocket revisions (n = 2), for recurrent IAT despite reprogramming (n = 1) and ineffective therapy during arrhythmic storm (n = 1). Eight patients (22.2%) died, 3 patients (9%) underwent LVAD implantation due refractory HF during follow-up. Six patients died because of refractory HF, 1 patient died due to intracerebral hemorrhage and 1 due to sarcoidosis. There were no documented deaths associated with the procedure or the S–ICD system itself. No patient had the device removed because of a perceived need for antitachycardia pacing (ATP) or the necessity of pacing or cardiac resynchronization therapy despite 9 patients (25%) after TLE of a two–chamber ICD and one patient (3%) after TLE of a CRT–D. Univariate predictors of death included hypertension (HR 22.72; p = 0.02), diabetes (HR 10.64; p = 0.001), ischemic heart disease (HR 5.92; p = 0.01) and NYHA class > = II (p = 0.04). We did not observed any predictors for complications including IATs and device-related complications requiring surgical revision. Conclusions S–ICD implantaion after TLE of TV–ICD is safy and effective. Baseline clinical characterisctics including ischemic heart disease, diabetes, hypertension and NYHA class > = II are associated with worse survival.

P289 EYESHOT OF CARDIAC AMYLOIDOSIS CASES PRESENTED TO A CARDIOLOGY UO IN CENTRAL ITALY IN 2021

Abstract Introduction ATTR–related cardiac amyloidosis, caused by the accumulation of insoluble fibrillar proteins derived from transthyretin misfolding, is an often underdiagnosed pathology, especially when neurological involvement is absent or minor. Transthoracic echocardiography represents the first fundamental step in the diagnostic process. Abstract During the year 2021, a total of 9 patients with an echocardiographic feature of hypertrophic heart disease suggestive of infiltrative pathology were referred to our Cardiology unit. Of these patients, 89% were male (8 out of 9), aged between 60 and 88 years (average age of 72 years). The clinic presentation was heart failure in 5 cases (55% of the total), arrhythmic storm in 1 case, history of amyloid polyneuropathy in 1 case and it was an occasional finding in 2 patients who required a cardiological evaluation for other reasons. The 12–lead ECG documented atrial fibrillation arrhythmia in 4 out of 9 cases (44%) and sinus rhythm in the remaining 5 cases (56%). Transthoracic echocardiography revealed left ventricular hypertrophy with granular sparkling aspect of the SIV in all patients, with indexes of global systolic function preserved in 4 out of 9 cases (44%), moderately reduced in 3 out of 9 cases (33%) and severely reduced in the remaining 2 cases (22%). Diastolic dysfunction was present in all patients, with a restrictive pattern in 4 of 9 cases (44%). Myocardial scintigraphy with DPD was performed in 7 patients, which confirmed the suspicion of aTTR amyloidosis in 6 cases (Perugini Score = 2), in the remaining 2 patients the diagnostic procedure was not performed due to severe comorbidities. At present, diagnostic confirmation of aTTR amyloidosis has been confirmed by biopsy in 2 patients; a patient‘s biopsy is currently under analysis; 1 patient is on Patisiran therapy. Conclusions Cardiac amyloidosis represents a frequent clinical condition especially in the elderly population. In the light of the most recent therapeutic strategies, a correct and early etiopathogenetic diagnosis is of fundamental importance.

P175 ELECTROCARDIOGRAPHIC ELEMENTS ASSOCIATED WITH ARRHYTHMIC RISK IN BRUGADA SYNDROME

Abstract Introduction Brugada syndrome is an inherited disease characterized by an increased arrhythmic risk and sudden death. The type 1 ECG pattern is the only standard required to make a diagnosis but the stratification of arrhythmic risk remains a controversial element. Some electrocardiographic signs have been described as associated with an increased arrhythmic risk. We present a case of Brugada Syndrome in which different electrocardiographic elements of incremental risk could have predicted the later evolution of the clinical case. Clinical Case A 68–year–old male patient with family history of sudden cardiac death (brother 51aa) and occasional finding of Brugada type 1 ECG pattern (2009), implanted with Medtronic bicameral ICD device in primary prevention. The electrocardiogram shows type 1 Brugada pattern in the right precordials with characteristic ST–elevation, followed by a concave ST segment, one of the signs of association with an increased arrhythmic risk; first–degree AV block with a long PR (323 msec) associated with the presence of the SCN5A mutation and an increased risk of arrhythmic events and sudden cardiac death; in the end a fragmented QRS in V2 with extended duration (153 ms). At the next follow–up the patient had some episodes of arrhythmic storm, effectively treated by the device; in consideration of the arrhythmic burden, he was subjected to epicardial ablation and was also subjected to genetic analysis that was positive for pathological mutation on the SCN5A gene (SCN5A ex 22: c.3929C>T;p.Pro1310Leu). Conclusions Brugada Syndrome can be diagnosed from the type 1 ECG pattern, but the current risk stratification score remains a controversial element. Electrocardiographic signs of malignancy can contribute to create a multiparametric evaluation of the patient in order to predict future arrhythmic events. Fig 1. ECG: RS 74 bpm, first–degree AV block (PR 323 msec), BFA, Brugada type 1 pattern (QRS 153 ms), fragmented QRS in V2. Fig. 2 Family tree.

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

Abstract 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.

C66 LONG TERM FOLLOW–UP OF PATIENTS WITH BIOPSY– PROVEN DIAGNOSIS OF MYOCARDITIS AND VENTRICULAR ARRHYTHMIAS

Abstract Background The diagnosis and management of patients with myocarditis with ventricular arrhythmic (VA) onset is one of the major challenging issues faced by physicians. Objective We aimed at evaluating the natural history of patients with an endomyocardial biopsy–proven diagnosis of myocarditis with a VA manifestation at the time of diagnosis. Methods From January 2013 to October 2021, 243 consecutive patients with unexplained VAs underwent a complete diagnostic work–out, including endomyocardial biopsy. All patients with a biopsy–proven diagnosis of myocarditis were included in the study. Results 104 patients were enrolled (mean age: 54 ± 16 years; 75% male). The presenting arrhythmic manifestation was syncope/aborted sudden death in 21 (20.2%) patients, sustained ventricular tachycardia (VT) in 16 (15.4%), nonsustained VT in 29 (27.9%) and frequent premature ventricular complexes in 38 (36.5%). Patients with severe systolic dysfunction (Ejection Fraction<35%) were 63.5%. Late gadolinium enhancement (LGE) and myocardial oedema were detected at cardiac magnetic resonance (CMR) in 91.8% and 30% patients, respectively. Thirty–eight (36.5%) patients received an implantable cardioverter defibrillator (ICD) for primary (n = 14; 36.8%) or secondary (n = 24; 63.2%) prevention of sudden cardiac death (SCD). The mean follow–up was 69 ± 32 months: cardiovascular (CV) death was 15.4% while the recurrence of sustained Vas was 27.9%. Among ICD patients, 13 (34.2%) had an appropriated therapy of the device and arrhythmic storm occurred in 3 (23.1%) of them. The combined endpoint of sustained VA/ICD therapy/CV death occurred in 35.6%. The most important independent predictor of VAs was the presence of LGE [Odds Ratio: 9.100; Confidence of Interval: 1.125 – 73.609; p–value: 0.04]. Conclusion Among patients with a diagnosis of myocarditis and VAs, 35.6% had recurrences of VA/ICD therapy/CV death during follow–up. The presence of LGE at CMR stratifies the risk of VA recurrence.

PO-684-01 CLINICAL CHARACTERISTICS, THERAPY AND LONG-TERM OUTCOME OF SHORT-COUPLED IDIOPATHIC VENTRICULAR FIBRILLATION. A SYSTEMATIC REVIEW OF PUBLISHED CASE REPORTS WITH NEW EXTENDED LONG-TERM FOLLOW-UP

Short-coupled idiopathic ventricular fibrillation (SC-IVF) is a rare, potentially lethal arrhythmia, initiated by SC-PVCs. Only small series have been published. To assess the clinical characteristics, therapies and long-term outcomes of patients (pts) with SC-IVF. Data from all published case reports on SC-IVF/Polymorphic VT were collected. Inclusion criteria were normal cardiac work-up including during follow-up (FU), and documented SC-PVC-VF available for our analysis and ruling out early repolarization syndromes and CPVT at VF onset. Updated information was provided by 82% of authors contacted, with 22 additional ECG tracings provided. A total of 100 pts’ cases were identified, including 82 who met inclusion criteria. Mean FU increased from 2.75+3.6 years in the original publications to 10.5+7.9 years (p<0.0001). There were 42 (51%) males, aged 39.6+13.5 years at the time of SC-IVF diagnosis. Pts presented with syncope (40%), aborted cardiac arrest (ACA) (16%), ACA + arrhythmic storm (13%), arrhythmic storm (10%), ICD shocks (8%) or palpitations (1%). Prior history included syncope in 32 (39%) pts. Mean coupling interval of the SC-PVC was 293.6+50.7ms. Presumed sites of PVC origin were the RV, LV and RVOT in 54%, 21% and 5% of pts, respectively. A total of 69 (84%) pts had an ICD implanted before or after SC-IVF documentation. During long-term treatment with quinidine (n=11) or verapamil (n=32), SC-IVF did not recur in 82% and 50% of pts, respectively (p=0.08). Ablation was performed in 43 (92%) of the 47 pts in whom it was attempted. Ablation sites were the Purkinje RV (43%) or LV (23%), and the non-Purkinje RV (19%) or LV (2%). Acute and late success rates after a first ablation were 83% and 61.7%, respectively. A second ablation in 7 pts yielded a 74.5% total success rate. No difference was found in the success rate of quinidine compared with ablation procedures (p=0.6). During FU, 4 pts died including 2 from sudden cardiac death; both pts were treated with verapamil and refused ICD implantation. SC-IVF mainly presents following syncope. Quinidine and ablation procedures have comparable long-term high efficacy in arrhythmia control. The commonest sites of successful ablation are the RV and LV Purkinje fibers.

PO-717-08 UNUSUAL LETHAL COMPLICATION DURING SCAR-RELATED VT ABLATION: A CASE OF DRY TAMPONADE

Scar related ventricular tachycardia (VT) ablation has been shown to be more effective than anti-arrhythmic drugs in patients with ischemic cardiomyopathy (ICMP) and recurrent VT. In this particular population, complication rate can be as high as 10%, the most common ones being vascular damage, and pericardial complications. To identify a rare but severe complication of scar related VT ablation NA A 78 yo male with an old inferior and a recent anterior myocardial infarction (LVEF= 25%) was referred to our institution for VT ablation due to arrhythmic storm. Cardiac CT scan revealed inferior and anterior wall thinning (Inheart technology; figure panel A). Procedure was performed under conscious sedation in a stable patient. RF energy was delivered at 40 to 50W using a Smarttouch ST/SF catheter and the Carto 3 navigation system (Biosense Webster). After CT-channel ablation, a non clinical VT was induced. During ablation of this VT on the inferior wall, ST segment elevation in inferior leads became apparent, and arterial pressure dropped from 90 to 70mmHg. The patient was asymptomatic. Per-procedure coronary angiography showed no acute lesion and transthoracic echo demonstrated a dry pericardium. Ablation was continued and the patient was transferred to the ICU 1 hour later, with arterial pressure stabilized at 70 mm Hg. In the ICU, hemodynamic suddenly deteriorated 20 minutes after arrival and the patient went into cardiac arrest. After resuscitation, minimal pericardial effusion and clots were seen on TTE. Percutaneous pericardial drainage was attempted but failed to restore hemodynamics. The patient was then transferred to the operating room for surgical drainage. The diagnosis of circumferential intramyocardial hematoma contained by the epicardial layer (dry tamponade) was made (Figure panel B). Due to the extent of the hematoma, dilaceration of the myocardium and the clinical context, no further resuscitation was attempted and the patient finally died. This diagnosis of dry tamponade is rare in electrophysiology but well known by cardiologists performing chronic total occlusion angioplasty. It needs to be recognized by electrophysiologists at its early phase to avoid lethal outcome using hemodynamic support during the healing process.

Recent Insights Into Mechanisms and Clinical Approaches to Electrical Storm.

Electrical storm, characterized by repetitive ventricular tachycardia/ventricular fibrillation over a short period, is becoming more common with widespread use of implantable cardioverter defibrillator (ICD) therapy. Electrical storm, sometimes called "arrhythmic storm" or "ventricular tachycardia storm," is usually a medical emergency requiring hospitalization and expert management, and significantly affects short- and long-term outcomes. This syndrome typically occurs in patients with underlying structural heart disease (ischemic or nonischemic cardiomyopathy) or inherited channelopathies. Triggers for electrical storm should be sought but are often unidentifiable. Initial management is dictated by the hemodynamic status, whereas subsequent management typically involves ICD interrogation and reprogramming to reduce recurrent shocks, identification and management of triggers like electrolyte abnormalities, myocardial ischemia, or decompensated heart failure, and antiarrhythmic drug therapy or catheter ablation. Sympathetic nervous system activation is central to the initiation and maintenance of arrhythmic storm, so autonomic modulation is a cornerstone of management. Sympathetic inhibition can be achieved with medications (particularly β-adrenoreceptor blockers), deep sedation, or cardiac sympathetic denervation. More definitive management targets the underlying ventricular arrhythmia substrate to terminate and prevent recurrent arrhythmia. Arrhythmia targeting can be achieved with antiarrhythmic medications, catheter ablation, or more novel therapies, such as stereotactic radiation therapy, that target the arrhythmic substrate. Mechanistic studies point to adrenergic activation and other direct consequences of ICD shocks in promoting further arrhythmogenesis and hypocontractility. In this report, we review the pathophysiologic mechanisms, clinical features, prognosis, and therapeutic options for electrical storm. We also outline a clinical approach to this challenging and complex condition, along with its mechanistic basis.

Cardiac Transplantation Italian Allocation System Analysis: Single Center Results

<h3>Purpose</h3> Analyze the characteristic of donors and recipients in our center and the results of heart transplantations for the two different levels of priority according to Italian previous allocation system, urgent patients and elective ones. <h3>Methods</h3> From 2006 to August 2020, 306 heart transplantations were performed at our institution. Of them 54 (17.6%) in urgency. Reasons for urgency were: 24 patients on ECMO support, 8 on IABP and 13 on intravenous inotropes, 4 arrhythmic storms and 5 complicated LVAD. <h3>Results</h3> In the urgent population, recipients were predominantly male (68.5 % vs 77.4 % in the elective p=0.17) and significantly younger (46.4 vs 52.2 years, p=0.001). More patients were on ECMO support (42.6% vs 1.7% p=0.000), IABP (42.6 vs 6.7% p=0.000) and mechanically ventilated (46.2% vs 6% p=0.000) pre transplant. The donors of urgent patients were younger than donors of the elective ones (38.9 vs 42.4 years (p=0.06). Donor's gender (68% males) and cause of brain death (brain trauma 44,4%, and cerebral hemorrhage 35,2%) were comparable in the two groups. Mean ischemic time was longer in urgent cases (211 vs 191 minutes, p=0.01) as donations came from across the whole country. Severe Early Graft Failure (EGF) requiring ECMO occurred in 9.4% of patients in the urgent population vs 3.6% in the elective with no significant difference (p=0.076), as well as in hospital mortality that was 11.5% in urgent vs 8.3% (p=0.429). Recipients' risk factors for in-hospital mortality were age [OR 1.05 (1.01;1.09), p=0.028] and Glomerular Filtration Rate (GFR) < 40 ml/min [2.68 (1.04;6.92), p=0.047]. No donors' variable resulted to be a risk factor for in-hospital mortality. Episodes and grade of rejection did not diverge between groups, and so did follow up mortality (16.7% in urgent vs 22.4% in electives p=0.444) Mean follow up time for urgent population was shorter (53.6 vs 75.6 months (p=0.007). Overall 5 and 10 years' mortality was 79.7% and 62% vs 88.1% and 72.8% for urgent and elective patients respectively (p=0.721). <h3>Conclusion</h3> This retrospective analysis of our transplantation activity with the different priority regimen shows little differences in terms of mortality and complications. Despite the worse clinical characteristics of the urgent recipients and the longer ischemic time, results do not significantly differ from the elective population, underlying the importance of donation quality.

45 Experience of 5 years of balloon pulmonary angioplasty in a single centre: safety and short-term results

Abstract Aims Balloon pulmonary angioplasty (BPA) has recently been developed as a treatment strategy for chronic thromboembolic pulmonary hypertension (CTEPH) but efficacy and technical safety have to be established. We examine the effects of BPA on patients with inoperable disease or residual pulmonary hypertension (PH) after pulmonary endarterectomy (PEA). Methods and results From 2015 to 2020 we enrolled symptomatic inoperable CTEPH patients and patients with residual PH after PEA. At baseline and 3 months after last BPA session patients underwent clinical evaluation, 6-min walking distance (6MWD), and right heart catheterization. Friedman test with Bonferroni post-hoc pairwise analysis was used. Fifty patients [male 42%, median age 68 (51–74) years, 42 inoperable, and 8 with residual PH after PEA] were treated for a total of 156 sessions (median 2 sessions/patient); during each session we treated 2.3 (2.2–2.7) vessels. Results are shown in the Table. Forty-nine patients were treated with medical therapy before BPA (19 with combination therapy). Five pulmonary artery dissection and two haemoptysis with clinical impairment were documented during the procedures; 37 patients had lung injury (radiographic opacity with/without haemoptysis and/or hypoxaemia), none had renal dysfunction, 7 patients had access site complications. Seven patients died during follow-up (none within 30 days from the procedure) because of sepsis (1), heart failure (1), cancer (2), arrhythmic storm (2), and sudden death in patients with severe coronary atherosclerosis (1). Conclusions BPA is a safe and effective treatment able to improve symptoms and haemodynamic profile. 45 Table 16MWD, six minute walking distanceCI, cardiac index; mPAP, mean pulmonary arterial pressure; PAC, pulmonary arterial compliance; PVR, pulmonary vascular resistance; RAP, right atrial pressure; SvO2, mixed venous oxygen saturation; WHO-FC, World Health Organization functional class.

462 Accidental detection of an anomalous origin of the coronary arteries in a patient with STEMI: a case report

Abstract Coronary artery anomalies and variants are relatively uncommon congenital disorders of the coronary artery anatomy and constitute the second most common cause of sudden cardiac death in young competitive athletes. Normally there are two main coronary arteries, which stem from the sinuses of Valsalva and descend towards the cardiac apex. The most frequent anomalous origin of the coronary arteries associated with sudden cardiac death is the anomalous origin of a coronary artery from the contralateral sinus, particularly if the anomalous coronary artery has a course between the aorta and the pulmonary artery. The diagnosis of a coronary artery anomaly is insidious since patients are usually asymptomatic. Indeed, in most of the cases, coronary anomalies are discovered incidentally during coronary angiography or on autopsy following sudden cardiac death. However, in some cases, symptoms like angina, syncope, heart failure, and myocardial infarction may occur. We want to describe the case of a 54 years old man who went to another hospital of our district with chest pain. The EKG showed an infero-lateral STEMI. The patient underwent systemic thrombolysis complicated by arrhythmic storm, treated with effective DC shock, then he was urgently transferred to our Hospital to perform a PCI rescue. The coronary angiography showed a critical stenosis of the right coronary artery, treated with the implantation of a zotarolimus-eluting coronary stent system. Surprisingly, an abnormal origin of the anterior interventricular artery and circumflex artery from seperated hosts in the right coronary sinus was detected. A computed tomography showed the separated origin of the right coronary artery and the left main from the right coronary sinus; moreover, the left main presented a retroaortic course between the bulb and the left atrium; the left anterior intraventricular artery run anterior to the aortic root. During hospitalization, a diagnosis of diabetes was made with consequent setting of adequate hypoglycemic therapy. Serial echocardiograms showed an improval in the ejection fraction (from 35–40% to 50%). The patient was discharged in well clinical conditions and 1 month later at the follow-up, during an outpatient visit, he was fully asymptomatic. The dynamic EKG according to Holter showed rare isolated ventricular beats; laboratory tests were normal. The anomalous origin of a coronary ostium from the contralateral sinus is the most frequently anomaly which is associated with sudden cardiac death, in particular when the left coronary artery origins from the right sinus. The rapid advancement of the imaging techniques, including CT, CMR, intravascular ultrasound, and optical coherence tomography, have provided us with a wealth of new information on this subject. Coronary artery CT offers the best performance in terms of spatial resolution, acquisition time, and image contrast but the use is limited due the dose of ionizing radiation and the use of contrast agents, in particular taking into account that most patients are young. CMR is capable of visualizing the origin of the coronary arteries non-invasively, without use of ionizing radiation and contrast agents. Currently however, due to spatial resolution, the capability of CMR to visualize smaller coronary branches is still a limiting factor preventing full assessment of coronary arteries using this modality. Developments and more widespread access to advanced cardiac imaging will undoubtedly lead to earlier diagnoses. The taxonomies of the anomalous origin of coronary arteries are inconsistent and complex and so we want to make our contribution to the register of cases of abnormal origin of coronary arteries for the risk of sudden cardiac death and ischaemic events related to.

Lactate levels as a prognostic predict in cardiogenic shock under venoarterial extracorporeal membrane oxygenation support

Introduction and objectivesLactate and its evolution are associated with the prognosis of patients in shock, although there is little evidence in those assisted with an extracorporeal venoarterial oxygenation membrane (VA-ECMO). Our objective was to evaluate its prognostic value in cardiogenic shock assisted with VA-ECMO. MethodsStudy of patients with cardiogenic shock treated with VA-ECMO for medical indication between July 2013 and April 2021. Lactate clearance was calculated: [(initial lactate − 6 h lactate) / initial lactate × exact time between both determinations]. ResultsFrom 121 patients, 44 had acute myocardial infarction (36.4%), 42 implant during cardiopulmonary resuscitation (34.7%), 14 pulmonary embolism (11.6%), 14 arrhythmic storm (11.6%), and 6 fulminant myocarditis (5.0%). After 30 days, 60 patients (49.6%) died, mortality was higher for implant during cardiopulmonary resuscitation than for implant in spontaneous circulation (30 of 42 [71.4%] vs 30 of 79 [38.0%], P=.030). Preimplantation GPT and lactate (both baseline, at 6hours, and clearance) were independently associated with 30-day mortality. The regression models that included lactate clearance had a better predictive capacity for survival than the ENCOURAGE and ECMO-ACCEPTS scores, with the area under the ROC curve being greater in the model with lactate at 6 h. ConclusionsLactate (at baseline, 6h, and clearance) is an independent predictor of prognosis in patients in cardiogenic shock supported by VA-ECMO, allowing better risk stratification and predictive capacity.

Comparison of the arrhythmogenic substrate for ventricular tachycardia in patients with ischemic vs non-ischemic cardiomyopathy - insights from high-density, multi-electrode catheter mapping.

The purpose of this study was to compare the differences of arrhythmogenic substrate using high-density mapping in ventricular tachycardia (VT) patients with ischemic (ICM) vs non-ischemic cardiomyopathy (NICM). Data from patients presenting for VT ablation from December 2016 to December 2020 at Westmead Hospital were reviewed. Sixty consecutive patients with structural heart disease (ICM 57%, NICM 43%, mean age 66years) having catheter ablation of scar-related VT with pre-dominant left ventricular involvement were included. ICM was associated with larger proportion of dense scar area (bipolar; 19 [12-29]% vs 6 [3-10]%, P < 0.001, unipolar; 20 [12-32]% vs 11 [7-19]%, P = 0.01) compared with NICM. However, the scar ratio (unipolar dense scar [%]/bipolar dense scar [%]) was significantly higher in NICM patients (1.2 [0.8-1.7] vs 1.7 [1.3-2.3], P = 0.003). Larger scar area in ICM was paralleled by higher proportion of complex electrograms (6 [2-13] % vs 3 [1-5] %, P = 0.01), longer and wider voltage based conducting channels, higher incidence of late potential-based conducting channels, longer VT cycle-length (399 ± 80ms vs 359 ± 68ms, P = 0.04) and greater maximal stimulation-QRS interval among sites with good pace-map correlation (75 [51-99]ms vs 48 [31-73]ms, P = 0.02). Ventricular arrhythmia (VA) storm was more highly prevalent in ICM than NICM (50% vs 23%, P = 0.03). During the follow-up period, NICM had a significantly higher cumulative incidence for the VA recurrence than ICM (P = 0.03). High-density multi-electrode catheter mapping of left ventricular arrhythmogenic substrate of NICM tends to show smaller dense scar area and higher scar ratio, compared with ICM, suggestive the extent of epicardial/intramural substrate, with paucity of substrate targets for ablation, which results in the worse outcomes with ablation.

A new biomarker that predicts ventricular arrhythmia in patients with ischemic dilated cardiomyopathy: Galectin-3.

Ventricular arrhythmias are caused by scar tissue in patients with ischemic dilated cardiomyopathy. The gold standard imaging technique for detecting scar tissue is magnetic resonance imaging (MRI). However, MRI is not feasible for use as a screening test, and also cannot be used in patients who have received an implantable cardioverter-defibrillator (ICD). In this study, we aimed to assess the association between levels of galectin-3 (Gal-3), which is known to be secreted by scar tissue, and the history of ventricular arrhythmias in patients with ischemic dilated cardiomyopathy who received an ICD. Nineteen healthy controls and 32 patients who had previously undergone VVI-ICD implantation due to ischemic dilated cardiomyopathy were enrolled in the study. Patients were divided into three groups: the first group including patients who had received no ICD therapies, the second including patients with arrhythmia requiring therapies with no arrhythmia storm, and the third including patients who had arrhythmia storm. We assessed the association between Gal-3 levels and the history of ventricular arrhythmias in these patients. Gal-3 levels were significantly higher in the patient groups than in the control group (p<0.01). Gal-3 levels of patients with arrhythmias requiring ICD therapies were significantly higher than in patients with ICD not requiring therapies (p=0.02). They were also higher in patients with a history of arrhythmia storm than in patients without shocks (p=0.05). Receiver operating curve analysis showed with 84% sensitivity and 75% specificity that Gal-3 levels over 7 ng/ml indicated ventricular arrhythmia that required therapies. Gal-3 may be used to further improve risk stratification in patients with ischemic cardiomyopathy who are more prone to developing life-threatening arrhythmias.

Impact of substrate-based ablation for ventricular tachycardia in patients with frequent appropriate implantable cardioverter-defibrillator therapy and dilated cardiomyopathy: Long-term experience with high-density mapping

IntroductionRecurrent ventricular tachycardia (VT) episodes have a negative impact on the clinical outcome of implantable cardioverter-defibrillator (ICD) patients. Modification of the arrhythmogenic substrate has been used as a promising approach for treating recurrent VTs. However, there are limited data on long-term follow-up. AimTo analyze long-term results of VT substrate-based ablation using high-density mapping in patients with severe left ventricular (LV) dysfunction and recurrent appropriate ICD therapy. MethodsWe analyzed 20 patients (15 men, 55% with non-ischemic cardiomyopathy, age 58±15 years, LV ejection fraction 32±5%) and repeated appropriate shocks or arrhythmic storm (>2 shocks/24 h) despite antiarrhythmic drug therapy and optimal heart failure medication. All patients underwent ventricular programmed stimulation (600 ms/S3) to document VT. A sinus rhythm (SR) voltage map was created with a three-dimensional electroanatomic mapping system (CARTO, Biosense Webster, CA) using a PentaRay® high-density mapping catheter (Biosense Webster, CA) to delineate areas of scarred myocardium (ventricular bipolar voltage ≤0.5 mV – dense scar; 0.5-1.5 mV – border zone; ≥1.5 mV – healthy tissue) and to provide high-resolution electrophysiological mapping. Substrate modification included elimination of local abnormal ventricular activities (LAVAs) during SR (fractionated, split, low-amplitude/long-lasting, late potentials, pre-systolic), and linear ablation to obtain scar homogenization and dechanneling. Pace-mapping techniques were used when capture was possible. The LV approach was retrograde in nine cases, transseptal in five and epi-endocardial in four. In two patients ablation was performed inside the right ventricle. ResultsLAVAs and scar areas were modified in all patients. Mean procedure duration was 149 min (105-220 min), with radiofrequency ranging from 18 to 70 min (mean 33 min) and mean fluoroscopy time of 15 min. Non-inducibility was achieved in 75% of cases (in four patients with hemodynamic deterioration and an LV assist device, VT inducibility was not performed). There were two cases of pericardial tamponade, drained successfully. During a follow-up of 50±24 months, 65% had no VT recurrences. Among the seven patients with recurrences, three underwent redo ablation and four, with fewer VT episodes, received appropriate ICD therapy. There were five hospital readmissions due to heart failure decompensation, one patient died in the first week after unsuccessful ablation of a VT storm and three died (stroke and pneumonia) >1 year after ablation. ConclusionCatheter ablation based on substrate modification is feasible and safe in patients with frequent VTs and severe LV dysfunction. This approach may be of clinical relevance, with potential long-term benefits in reducing VT burden.

A new biomarker that predicts ventricular arrhythmia in patients with ischemic dilated cardiomyopathy: Galectin-3

IntroductionVentricular arrhythmias are caused by scar tissue in patients with ischemic dilated cardiomyopathy. The gold standard imaging technique for detecting scar tissue is magnetic resonance imaging (MRI). However, MRI is not feasible for use as a screening test, and also cannot be used in patients who have received an implantable cardioverter-defibrillator (ICD). In this study, we aimed to assess the association between levels of galectin-3 (Gal-3), which is known to be secreted by scar tissue, and the history of ventricular arrhythmias in patients with ischemic dilated cardiomyopathy who received an ICD. MethodsNineteen healthy controls and 32 patients who had previously undergone VVI-ICD implantation due to ischemic dilated cardiomyopathy were enrolled in the study. Patients were divided into three groups: the first group including patients who had received no ICD therapies, the second including patients with arrhythmia requiring therapies with no arrhythmia storm, and the third including patients who had arrhythmia storm. We assessed the association between Gal-3 levels and the history of ventricular arrhythmias in these patients. ResultsGal-3 levels were significantly higher in the patient groups than in the control group (p<0.01). Gal-3 levels of patients with arrhythmias requiring ICD therapies were significantly higher than in patients with ICD not requiring therapies (p=0.02). They were also higher in patients with a history of arrhythmia storm than in patients without shocks (p=0.05). Receiver operating curve analysis showed with 84% sensitivity and 75% specificity that Gal-3 levels over 7 ng/ml indicated ventricular arrhythmia that required therapies. ConclusionGal-3 may be used to further improve risk stratification in patients with ischemic cardiomyopathy who are more prone to developing life-threatening arrhythmias.

Arrythmic storm in patients with and without an implantable cardioverter defibrillator

Abstract Introduction Available data on arrhythmic storm (AS) is frequently obtained from retrospective observational series of patients who carry an implantable cardioverter defibrillator (ICD). Therefore, this selection bias limits the evidence regarding mortality and prognosis of patients with AS who do not have an ICD. Purpose Describe and compare the epidemiological and clinical characteristics, treatment, and outcomes of patients with and without an ICD, admitted for AS in the Acute Coronary Care Unit. Methods Between 2006 and 2020, 187 episodes of AS in 165 patients were identified in two third level hospitals. There were 71 patients without ICD and 116 patients with ICD. Clinical characteristics, treatment and outcome were analysed. Results Baseline characteristics are depicted in Figure 1. Risk profile of ICD carriers was worse (they were older, more frequently smokers, had more often hypertension, dyslipidemia, chronic kidney disease and thyroid disturbances, and had worse NYHA class). Known ejection fraction was also worse. AS aetiology was also different. Myocardial infarction was present only in non ICD carriers (56.3% vs 0, p&amp;lt;0.001) and was the most frequent cause of AS in this group. Ion disturbances were also more common among ICD carriers (60.3% vs 33.6%, p&amp;lt;0.001), but it was the most frequent aetiology of AS in non ICD carriers. Heart failure or cardiogenic shock (36.6% vs 26.7%, p=0.154), infection (7% vs 13.8%, p=0.156) and bradycardia with acquired long QT syndrome (11.3% vs 9.5%, p=0.695) were similar in both groups. There were two episodes of myocarditis among non ICD carriers. The predominant arrythmia was also different. Ventricular fibrillation was more common in non ICD carriers (43.7% vs 4.3%) while monomorphic ventricular tachycardia was more frequent in ICD carriers (38.8% vs 83.6%, p&amp;lt;0.001). Non ICD carriers had worse levels of pH (7.30 vs 7.42, p&amp;lt;0.001) and lactate (4.4mmol/L vs 2.0mmol/L, p&amp;gt;0.001) and required inotropic and vasopressor drugs more frequently due to haemodynamic instability (57.7% vs 10.3%, p&amp;lt;0.001), mechanical support with intra-aortic balloon pump (40.8% vs 1.7%, p&amp;lt;0.001), ECMO (8.5% vs 0%, p&amp;lt;0.001), and other mechanical assist devices (5.6% vs 0%, p=0.010), and oral intubation (71.8% vs 17.2%, p&amp;lt;0.001). Pharmacologic treatment is described in Figure 2. Non ICD carriers required more frequently percutaneous coronary intervention (59.2% vs 4.3%, p&amp;lt;0.001) and less frequently ventricular ablation (28.2 vs 46.6%, p=0.013). Therapeutic hypothermia was used only in non ICD patients due to out of hospital cardiac arrest (33.8% vs 0%, p&amp;lt;0.001). In-hospital mortality was higher in non ICD carriers (28.2% vs 11.2%, p=0.003). Conclusion Despite a worse cardiovascular profile in ICD carriers, AS is associated with a worse haemodynamic situation and mortality in non ICD carriers, due to different aetiology of the AS and to the absence of protection against sustained arrythmias. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): Beca para la Formaciόn e Investigaciόn en Cuidados Críticos Cardiolόgicos concedida por la Asociaciόn de Cardiopatía Isquémica y Cuidados Críticos Cardiolόgicosde la SEC Figure 1. Baseline CharacteristicsFigure 2. Pharmacological treatment

Arrythmic storm in patients with and without a myocardial infarction

Abstract Introduction Available data on arrhythmic storm (AS) is frequently obtained from retrospective observational series of patients who carry an implantable cardioverter defibrillator or who undergo ablation, and typically, patients with ST-elevation myocardial infarction (STEMI) as the cause of the AS are excluded. Therefore, this selection bias limits the evidence regarding mortality and prognosis of patients with AS due to STEMI. Purpose Describe and compare the epidemiological and clinical characteristics, treatment, and outcomes of patients admitted for AS in the Acute Coronary Care Unit due to STEMI and other causes. Methods Between 2006 and 2020, 187 episodes of AS in 165 patients were identified in two third level hospitals. There were 40 patients with STEMI and 147 patients with other causes of AS. Clinical characteristics, treatment and outcome were analysed. Results Baseline characteristics are depicted in Figure 1. Risk profile of patients without STEMI was worse (they were older, had more often hypertension, and thyroid disturbances, and had worse NYHA class). Patients with STEMI were more frequently smokers. Ejection fraction was higher among STEMI patients. Predisposing features for AS (apart from myocardial ischemia) were also different. Ion disturbances were more common among STEMI patients (37.4% vs 67.5%, p=0.001). Heart failure or cardiogenic shock (27.9% vs 40.0%, p=0.140), infection (12.2% vs 7.5%, p=0.399) and bradycardia with acquired long QT syndrome (10.2% vs 10.0%, p=0.695) were similar in both groups. There were two episodes of myocarditis in patients without STEMI. The predominant arrythmia was also different. Ventricular fibrillation was more common in STEMI patients (4.8% vs 72.5%) while monomorphic ventricular tachycardia was more frequent patients without STEMI (80.3% vs 7.5%, p&amp;lt;0.001). STEMI patients had worse levels of pH (7.40 vs 7.25, p&amp;lt;0.001) and lactate (2.25mmol/L vs 5.56mmol/L, p&amp;gt;0.001) and required inotropics and vasopressors more frequently due to haemodynamic instability (15.0% vs 77.5%, p&amp;lt;0.001), mechanical support with intra-aortic balloon pump (5.4 vs 57.5%, p&amp;lt;0.001), ECMO (2.0% vs 7.5%, p=0.082), and other mechanical assist devices (0 vs 10.0%, p&amp;lt;0.001), and oral intubation (23.8% vs 90.0%, p&amp;lt;0.001). Pharmacologic treatment is described in Figure 2. Obviously, STEMI patients required more often percutaneous coronary intervention (8.2% vs 87.5%, p&amp;lt;0.001) and less frequently ventricular ablation (50.3% vs 0, p&amp;lt;0.001). Therapeutic hypothermia was more commonly used in STEMI patients due to out of hospital cardiac arrest (2.0% vs 52.5%, p&amp;lt;0.001). In-hospital mortality was higher in STEMI patients (11.6% vs 42.5%, p&amp;lt;0.001). Conclusion Despite a worse cardiovascular profile in patients without STEMI, AS is associated with a worse haemodynamic situation and mortality in STEMI patients. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): Beca para la Formaciόn e Investigaciόn en Cuidados Críticos Cardiolόgicos concedida por la Asociaciόn de Cardiopatía Isquémica y Cuidados Críticos Cardiolόgicosde la SEC Figure 1. Baseline CharacteristicsFigure 2. Pharmacological treatment

Long-term outcome of patients with cardiolaminopathy undergoing defibrillator implantation: single-center experience

Abstract Background Mutations in the LMNA gene are associated with a high arrhythmic risk. The history of the disease in patients undergoing ICD implantation is poorly characterized. Purpose To evaluate the phenotype of patients with cardiolaminopathy at the time of first ICD implantation, the incidence, characteristics and timing of ventricular arrhythmias (VAs) during follow up and the predictive value of the European score (that assigns a point each to non-sustained VT (NSVT), left ventricular ejection fraction (LVEF)&amp;lt;45% at first contact, male sex and non-missense mutations) and of the Wahbi score (that also includes conduction disturbances) for both VAs and heart failure (HF) related outcomes. Methods Patients were identified retrospectively. Clinical and device data were collected at baseline and during follow-up. Results We identified 26 patients (54% male, 42±8 years, 31% with familial history of sudden cardiac death, 31% with non-missense mutation) undergoing ICD implantation, 96% in primary prevention, 47% with single chamber ICD, 38% with dual chamber ICD. At the time of implantation, 30% had skeletal muscle involvement, 15% history of syncope, 4% of cardiac arrest, 62% previous NSVT. Also, 38% had a history of supraventricular arrhythmias and 61% had AV conduction disturbances. LVEF was 41±11%, 35% were in NYHA class ≥2, the mean European and Wahbi scores were 2.1±0.8 and 18.2±8.9, respectively. During 8.3±5 years, 15% were transplanted, 8% died due to HF, 4% underwent LVAD implantation, despite 31% having received an upgrade to CRT-D. Appropriate device interventions occurred in 46% of patients with a median time to first event of 29 months (IQR 13–93), for a total of 137 ATP, 51% of which effective (median 3ATP/patient, IQR 1–8) and of 26 shocks, 96% of which effective (median 2 shocks/patient, IQR 1–3); 12% had an arrhythmic storm. The first treated arrhythmia was a polymorphic VT/VF in 17%, a monomorphic VT in the others (medium cycle length 293±37 msec). Survival free from appropriate ICD interventions at 1 and at 5 years was 75% and 19% respectively in case of a European score ≥3 vs 94% and 82% in case of a score &amp;lt;3 (Logrank test p&amp;lt;0.01), 72% and 46% in case of Wahbi score ≥30 vs 100% and 86% with score &amp;lt;30 (p&amp;lt;0.01), with no differences in terms of death/transplant (figure). At last follow-up, 92% of patients a were taking beta-blocker, 42% amiodarone, 8% sotalol, 4% flecainide, 8% mexiletine. Also, 4% had undergone invasive VT ablation, 8% bilateral cardiac sympathetic denervation. Conclusions Patients with cardiolaminopathy are at a high risk of both arrhythmic and heart failure progression over the first decade after implantation of the first ICD. A European score ≥3 identifies patients with 5-year shock/ATP free survival of less than 20% but does not predict death/transplantation. The first arrhythmic event in these patients is more frequently a rapid monomorphic VT with modest ATP efficacy. Funding Acknowledgement Type of funding sources: None.

Catheter ablation supported by extracorporeal membrane oxygenation -last resort treatment of arrhythmic storm?

Abstract Introduction Arrhythmic storm (AS) is associated with high mortality, even with best medical care and hemodynamic support. If medical therapeutic failure, electrophysiological mapping and ablation are potential lifesaving therapies. Venoarterial extracorporeal membrane oxygenation (VA-ECMO) provides temporary mechanical circulatory support and can be used as a salvage intervention in patients with cardiogenic shock. Considering the seriousness of AS and the technical complexity involved, catheter ablation supported by VA-ECMO is infrequently performed. We sought to assess the safety and effectiveness of emergent catheter ablation procedures performed in patients on VA-ECMO at our hospital. Methods Retrospective study of all ventricular tachycardia (VT) catheter ablation procedures performed with VA-ECMO support at a tertiary centre between 2016 and 2020. Follow-up data was obtained from review of electronical records. Results Five patients underwent 6 emergent VT ablation procedures due to AS. The median age was 62 years (range, 52) and 4 patients were men. Three patients had VT at admission, while 2 were admitted with an acute coronary syndrome and developed VT during the hospitalization. Four patients had ischemic heart disease, though only 1 had previous history of VT; the remaining patient presented no structural heart disease. Median left ventricle ejection fraction was 11% (range 30). All patients had incomplete response to amiodarone, lidocaine or overdrive pacing, before being proposed to catheter ablation. Four patients were on ECMO support before ablation, while 1 was cannulated during the procedure due to hemodynamic instability. Ablation was performed using a retrograde approach in 3 patients, and combined retrograde and transeptal access in 2; one patient had epicardial ablation after unsuccessful endovascular approach. Three patients had left ventricle substrate ablation and the remaining 2 of the right ventricle. No major complications were seen directly related to the procedures. The median length of stay in intensive care unit was 22 days (range 41 days). Weaning of VA-ECMO was accomplished in all patients. Two patient died during the same hospitalization (one due to uncontrolled arrhythmic events). At a median 23 months (range 31) of follow-up of the surviving patients, two had recurrence of VT but no one had return of AS. Conclusion In our sample VT ablation on VA-ECMO support was a safe procedure, with no immediate complications. However, as reported in the literature, a high mortality rate was observed both in-hospital and during follow-up, mostly related to advanced structural heart disease. Also, considerable VT recurrence rates were seen, but with no re-hospitalization. Our experience shows that catheter ablation is a life-saving procedure in otherwise uncontrollable AS and allowed absolute success in weaning VA-ECMO. Funding Acknowledgement Type of funding sources: None.