Sustained Ventricular Fibrillation Research Articles

CE-452775-2 MARS-HCM: MULTI-MODAL DEEP LEARNING METHOD FOR VENTRICULAR ARRHYTHMIA (VA) RISK STRATIFICATION IN HYPERTROPHIC CARDIOMYOPATHY (HCM) PATIENTS

Current clinical guidelines by the AHA/ACC and ESC remain inadequate for accurately identifying HCM patients at risk for sudden cardiac death (SCD) by VA. Although risk factors for SCD in HCM patients have been established previously, including demographics, lab tests, late gadolinium-enhanced magnetic resonance imaging (LGE-MRI) features, it is challenging to integrate these distinct data types in a predictive model. Whether deep learning can integrate clinical covariates and LGE-MRI images in a multi-modal predictor that stratifies VA risk in HCM patients better than current clinical guidelines has not been explored. To develop a multi-modal deep learning approach that stratifies the risk of VA (sustained VT or VF) in HCM patients using raw LGE-MRI images and clinical covariates. In a single-center retrospective study, LGE-MRI images and electronic health record (EHR) data (demographics, clinical risk factors, echocardiogram features, LGE-MRI features) were acquired from 819 HCM patients. We developed a deep learning model with two input branches for images and EHR. In the image branch, the left ventricle (LV) was automatically segmented from LGE-MRI images, and the LV with raw image intensities was fed into a 3D ResNet. We adopted a feedforward network for the EHR branch to learn patterns from clinical covariates. In the output, the model was trained to synergistically fuse knowledge from both branches for VA prediction. In a 5-fold cross-validation, the multi-modal model using both LGE-MRI and EHR identified HCM patients with VA with an area under the ROC curve (AUC) of 0.83 (Figure), outperforming single-modal models using either LGE-MRI (AUC=0.80) or EHR (AUC=0.79). As a comparison, AHA/ACC guidelines had an AUC of 0.65 with a sensitivity of 0.81 and specificity of 0.44; ESC guidelines had an AUC of 0.69 with a sensitivity of 0.94 and specificity of 0.22. While preserving the same level of sensitivity as AHA/ACC guideline, the multi-modal model achieved higher specificity, 0.66. The VA risk score by the multi-modal model also showed a higher correlation coefficient (r=0.16) with other future adverse events (ICD shock, death, etc.) than risk scores by AHA/ACC (r=0.06) and ESC (r=0.01); see Figure. Our multi-modal deep learning significantly improved the prediction of VA in HCM patients compared with single-modal models and current clinical guidelines. Our model has the potential to improve the precision of VA risk stratification in HCM patients.

Relationship between myocardial bridging and fatal ventricular arrhythmias in patients with hypertrophic cardiomyopathy: the HCM-MB study.

Myocardial bridging (MB) and hypertrophic cardiomyopathy (HCM) are associated with the risk of fatal ventricular arrhythmias (VAs). The goal of the study was to determine the relationship between MB and fatal VAs in HCM patients with implantable cardiac defibrillators (ICD). Atotal of 108 HCM patients (mean age: 46.6 ± 13.6years; male:73) were enrolled in this retrospective study. All patients underwent transthoracic echocardiography and coronary computed tomography angiography. Fatal VAs including sustained ventricular tachycardia and ventricular fibrillation were documented in ICD records. There were documented fatal VAs in 29 (26.8%) patients during amean follow-up time of 71.3 ± 30.9months. Compared with the other groups, the fatal VA group had a higher incidence of the following: presence of MB (82.8 vs. 38%, p < 0.001), deep MB (62.1 vs. 6.3%, p < 0.001), very deep MB (24.1 vs. 0%, p < 0.001), long MB (65.5 vs. 11.4%, p < 0.001), presence of > 1MB (17.2 vs. 0%, p = 0.001), and MB of the left anterior descending artery (79.3 vs. 17.7%, p < 0.001) . Sudden cardiac death (SCD) risk score (hazard ratio: 1.194; 95% CI: 1.071-1.330; p = 0.001) and presence of MB (hazard ratio: 3.815; 95% CI: 1.41-10.284; p = 0.008) were found to be independent predictors of fatal VAs in HCM patients. The current data suggest that the SCD risk score and presence of MB were independent risk factors for fatal VAs in patients with HCM. In addition to conventional risk factors, the coronary anatomical course can provide clinicians with valuable information when assessing the risk of fatal VAs in HCM patients.

Cardiac magnetic resonance imaging T1 mapping and late gadolinium enhancement entropy: Prognostic value in patients with systemic sclerosis

BackgroundSystemic sclerosis (SSc) affects the myocardium, thereby resulting in a poor prognosis. Late gadolinium enhancement (LGE) entropy, derived from routine cardiac magnetic resonance (CMR) LGE images, is an index that reflects the complexity of the left ventricular myocardium. The aim of this study was to investigate whether LGE entropy can serve as a prognostic factor in patients with SSc. MethodsTwenty-four patients with SSc, who underwent CMR-T1 mapping and LGE to identify myocardial damage, were enrolled, and LGE entropy was measured. Extracellular volume (ECV) values were calculated using the same CMR-LGE images. The endpoint was major adverse cardiac events (MACEs), comprising all-cause death, hospitalization due to heart failure, and the onset of sustained ventricular tachycardia and ventricular fibrillation. The ability to predict MACE was assessed using receiver operating characteristic (ROC) analysis, and the predictability of LGE entropy was analyzed using Kaplan–Meier analysis. ResultsThe ROC curve analysis demonstrated a cut-off value of 7.39 for MACE with LGE entropy and had a sensitivity and specificity of 80 % and 79 %, respectively. Patients with LGE entropy ≥7.39 had a significantly higher MACE rate than those with LGE entropy <7.39 (p = 0.010). Moreover, LGE entropy ≥7.39 was a poor prognostic factor in patients without elevated ECV values. ConclusionsLGE entropy can be used to predict MACE and allows for further risk stratification in addition to ECV determination.

Abnormal Mechanics Relate to Myocardial Fibrosis and Ventricular Arrhythmias in Patients With Mitral Valve Prolapse.

The relation between ventricular arrhythmia and fibrosis in mitral valve prolapse (MVP) is reported, but underlying valve-induced mechanisms remain unknown. We evaluated the association between abnormal MVP-related mechanics and myocardial fibrosis, and their association with arrhythmia. We studied 113 patients with MVP with both echocardiogram and gadolinium cardiac magnetic resonance imaging for myocardial fibrosis. Two-dimensional and speckle-tracking echocardiography evaluated mitral regurgitation, superior leaflet and papillary muscle displacement with associated exaggerated basal myocardial systolic curling, and myocardial longitudinal strain. Follow-up assessed arrhythmic events (nonsustained or sustained ventricular tachycardia or ventricular fibrillation). Myocardial fibrosis was observed in 43 patients with MVP, predominantly in the basal-midventricular inferior-lateral wall and papillary muscles. Patients with MVP with fibrosis had greater mitral regurgitation, prolapse, and superior papillary muscle displacement with basal curling and more impaired inferior-posterior basal strain than those without fibrosis (P<0.001). An abnormal strain pattern with distinct peaks pre-end-systole and post-end-systole in inferior-lateral wall was frequent in patients with fibrosis (81 versus 26%, P<0.001) but absent in patients without MVP with basal inferior-lateral wall fibrosis (n=20). During median follow-up of 1008 days, 36 of 87 patients with MVP with >6-month follow-up developed ventricular arrhythmias associated (univariable) with fibrosis, greater prolapse, mitral annular disjunction, and double-peak strain. In multivariable analysis, double-peak strain showed incremental risk of arrhythmia over fibrosis. Basal inferior-posterior myocardial fibrosis in MVP is associated with abnormal MVP-related myocardial mechanics, which are potentially associated with ventricular arrhythmia. These associations suggest pathophysiological links between MVP-related mechanical abnormalities and myocardial fibrosis, which also may relate to ventricular arrhythmia and offer potential imaging markers of increased arrhythmic risk.

Idiopathic ventricular fibrillation associated with long-coupled Purkinje ectopy.

Idiopathic ventricular fibrillation (IVF) is mainly associated with and triggered by short-coupled (R-on-T) ventricular ectopics. However, little is known about the risk of VF associated with long-coupled premature ventricular complexes (LCPVCs). To examine the prevalence and characteristics of IVF patients presenting with LCPVCs. Consecutive patients with IVF and PVCs from fivearrhythmia referral centers were reviewed. We included patients presenting LCPVCs, defined as PVCs falling after the end of the T wave, with a normal QTc interval. We evaluated demographics, medical history, and clinical circumstances associated with PVCs and VF episodes. The origin of PVCs was determined by invasive mapping. Seventy-nine patients with IVF were reviewed. Among them, 12 (15.2%) met the inclusion criteria (8 women, age 36 ± 14 years). Eleven patients had documented LCPVCs initiating repetitive PVCs or sustained VF, whereas 1had only documented isolated PVCs. In 10 of 12 patients, PVCs were recorded showing both long and short coupling intervals of 418 ± 46and 304 ± 33 ms, respectively. Mapping showed that PVCs originated from the left Purkinje in 10 patients, from the right Purkinje in 1 patient, and both in 1 patient. Compared to other patients from the initial cohort, IVF with LCPVCs was associated with a left-sided origin of PVCs (92% in long-coupled IVF vs. 46% of left Purkinje PVCs in short-coupled IVF, p = .004). Long-coupled fascicular PVCs, traditionally recognized as benign, can be associated with IVF in a subset of patients. They can induce IVF by themselves or in association with short-coupled PVCs.

Successful percutaneous coronary intervention with extracorporeal membrane oxygenation in a patient with acute inferior wall myocardial infarction complicated by electrical storm, cardiogenic shock, and cardiac arrest: a case report

BackgroundHigh-risk patients with coronary heart disease who develop acute myocardial infarction (AMI) have severe coronary lesions. If severe complications occur, such as malignant ventricular arrhythmia, cardiogenic shock, and cardiac arrest, implementation of emergency percutaneous coronary intervention (PCI) may be hindered, leading to a higher perioperative mortality rate. Extracorporeal membrane oxygenation (ECMO) can pave the way for rapid myocardial reperfusion therapy. When cardiac arrest occurs, hemodynamic support with ECMO can facilitate revascularization with PCI, which can increase the time available for further salvage and treatment and reduce intraoperative risk during PCI.Case presentationHerein, we report a case of a 61-year-old man with AMI who suffered electrical storm of sustained malignant ventricular fibrillation, cardiogenic shock, and cardiac arrest and was successfully treated with PCI with ECMO support. During PCI, repeated aspiration and removal of the right coronary artery thrombus were performed, and blood flow was restored after right coronary artery balloon dilation. One episode of defibrillation was delivered to restore sinus rhythm. Then, stents were implanted in the distal and proximal right coronary artery lesions to achieve revascularization. After PCI with ECMO support, irreversible malignant arrhythmia returned to sinus rhythm through coronary perfusion, which prevented death following unsuccessful cardiopulmonary resuscitation. After applying active treatments, including anti-shock, mechanical ventilation, anti-inflammation, and organ support, the patient was discharged after his condition and vital signs stabilized. The patient was followed up once a week after hospital discharge, and his cardiopulmonary function recovered well.ConclusionsWith ECMO support, PCI should be performed immediately in patients with inferior wall AMI complicated by electrical storm of sustained ventricular fibrillation, cardiogenic shock, and cardiac arrest to facilitate stent placement, achieve complete revascularization, restore coronary perfusion, and avoid death

KCNH2 mutation c.3099_3112del causes congenital long QT syndrome type 2 with gender differences

IntroductionLong QT Syndrome (LQTS) is an inherited disease with an abnormal electrical conduction system in the heart that can cause sudden death as a result of QT prolongation. LQT2 is the second most common subtype of LQTS caused by loss of function mutations in the potassium voltage-gated channel subfamily H member 2 (KCNH2) gene. Although more than 900 mutations are associated with the LQTS, many of these mutations are not validated or characterized. Methods and resultsSequencing analyses of genomic DNA of a family with LQT2 identified a putative mutation. i.e., KCNH2(NM_000238.3): c.3099_3112del, in KCNH2 gene which appeared to be a definite pathogenic mutation. The family pedigree information showed a gender difference in clinical features and T-wave morphology between male and female patients. The female with mutation exhibited recurring ventricular arrhythmia and syncope, while two male carriers did not show any symptoms. In addition, T-wave in females was much flatter than in males. The female proband showed a positive reaction to the lidocaine test. Lidocaine injection almost completely blocked ventricular arrhythmia and shortened the QT interval by ≥30 ms. Treatment with propranolol, mexiletine, and implantation of cardioverter-defibrillators prevented the sustained ventricular tachycardia, ventricular fibrillation, and syncope, as assessed by a 3-year follow-up evaluation. ConclusionsA putative mutation c.3099_3112del in the KCNH2 gene causes LQT2 syndrome, and the pathogenic mutation mainly causes symptoms in female progeny.

Association between Frontal QRS-T Angle and Major Adverse Cardiovascular Events among Patients with Acute Myocardial Infarction: A Cross-sectional Study

Introduction: Acute myocardial infarction has reached epidemic proportions in the Indian population. The premature onset of acute myocardial infarction has shifted the focus of research. An abnormal frontal QRS-T angle can be used as a marker of acute myocardial infarction and can also predict Major Adverse Cardiac Events (MACE) such as heart failure, complex ventricular arrhythmias (sustained ventricular tachycardia or ventricular fibrillation), early post-infarction angina, mechanical complications, and cardiac death resulting from acute myocardial infarction. Predicting the likelihood of serious adverse cardiovascular events and mortality in patients who have experienced an acute myocardial infarction aids in developing immediate and short-term treatment plans. Aim: To assess the association between the Frontal QRS-T angle and MACE among patients with Acute Myocardial Infarction (MI). Materials and Methods: A cross-sectional study was conducted on adult patients admitted with a diagnosis of acute MI at the Department of Medicine, BLDE (Deemed to be University) Shri B.M. Patil Medical College Hospital and Research Centre, Vijayapura, Karnataka, India from January 2021 to June 2022. A total of 95 patients were enrolled in the study and classified into two groups: Group A (n=68) with a frontal QRS-T angle of &lt;100 degrees, and Group B (n=27) with a frontal QRS-T angle of &gt;100 degrees. The patients were monitored for the emergence of serious MACE such as heart failure, pulmonary oedema, cardiogenic shock, arrhythmias, and death while they were in the hospital. Statistical analysis was performed using the Chisquare test, Independent t-test, and Mann-Whitney U test as applicable. A p-value of &lt;0.05 was considered statistically significant. Results: The most common age group in Group A was 60-70 years, while in Group B it was 50-60 years. A total of 95 patients with acute MI were enrolled and divided into two groups. Out of 95 patients, 68 patients with a frontal QRS-T angle &lt;100 degrees were in Group A, and 27 patients with a frontal QRS-T angle &gt;100 degrees were in Group B. There was a significant difference between the two groups with respect to MACE, including heart failure (Group A=8.8%, Group B=77.8%, p=0.00), pulmonary oedema (Group A=10.3%, Group B=77.8%, p=0.00), and cardiogenic shock (Group A=7.4%, Group B=40.7%, p=0.00). Conclusion: A frontal QRS-T angle of &gt;100 degrees was a reliable factor for assessing in-hospital major adverse cardiac outcomes such as heart failure, pulmonary oedema, and cardiogenic shock. Hence, a frontal QRS-T angle of &gt;100 degrees on a 12-lead ECG is a cost-effective, reliable, and noninvasive parameter of MACE in patients with acute MI.

1134 IN-HOSPITAL ARRHYTHMIC BURDEN REDUCTION IN DIABETIC PATIENTS WITH ACUTE MYOCARDIAL INFARCTION TREATED WITH SGLT2-INHIBITORS: INSIGHTS FROM THE SGLT2-I AMI PROTECT STUDY

Abstract Background Sodium-glucose co-transporter 2 inhibitors (SGLT2-i) have shown significant cardiovascular benefits in patients with and without type 2 diabetes mellitus (T2DM). They have also gained interest for their potential anti-arrhythmic role and their ability to reduce the occurrence of atrial fibrillation (AF) and ventricular arrhythmias (VAs) in T2DM and heart failure patients. Objectives To investigate in-hospital new-onset cardiac arrhythmias in a cohort of T2DM patients presenting with acute myocardial infarction (AMI) treated with SGLT2-i vs. other oral anti-diabetic agents (non-SGLT2-i users). Methods Patients from the SGLT2-I AMI PROTECT registry (NCT05261867) were stratified according to the use of SGLT2-i before admission for AMI, divided into SGLT2-i users vs. non SGLT2-i users. In-hospital outcomes included the occurrence of in-hospital new-onset cardiac arrhythmias (NOCAs), defined as a composite of new-onset AF and sustained new-onset ventricular tachycardia (VT) and/or ventricular fibrillation (VF) during hospitalization. Results The study population comprised 646 AMI patients categorized into SGLT2-i users (111 patients) and non-SGLT2-i users (535 patients). SGLT2-I users had a lower rate of NOCAs compared with non-SGLT2-i users (6.3 vs.15.7%, p=0.010). Moreover, SGLT2-i was associated with a lower rate of AF and VT/VF considered individually (p = 0.032). In the multivariate logistic regression model, after adjusting for all confounding factors, the use of SGLT2-i was identified as an independent predictor of the lower occurrence of NOCAs (OR=0.35; 95%CI 0.14–0.86; p = 0.022). At multinomial logistic regression, after adjusting for potential confounders, SGLT2-I therapy remained an independent predictor of VT/VF occurrence (OR=0.20; 95%CI 0.04–0.97; p = 0.046) but not of AF occurrence. Conclusions In T2DM patients, the use of SGLT2-i was associated with a lower risk of new-onset arrhythmic events during hospitalization for AMI. In particular, the primary effect was expressed in the reduction of VAs. These findings emphasize the cardioprotective effects of SGLT2-i in the setting of AMI beyond glycemic control. Trial registration: Data are part of the observational international registry: SGLT2-I AMI PROTECT. ClinicalTrials.gov Identifier: NCT05261867.

Abstract 11589: Total Artificial Heart Placement in a Case of Recurrent Ventricular Tachycardia Storm

Background: Electrical storm is defined as three or more episodes of sustained ventricular tachycardia (VT) or ventricular fibrillation (VF) within a 24-hour period requiring termination by cardioversion, anti-tachycardia pacing (ATP) or defibrillation. It can be a particularly challenging syndrome to treat when refractory to standard of care therapies, which include antiarrhythmics, sedation, and ablation. We present a case of refractory electrical storm requiring total artificial heart placement (TAH) as a bridge to transplant. Case: A 65-year-old male with a history of idiopathic non-ischemic cardiomyopathy presented with VF arrest. After return of spontaneous circulation, he was admitted to the cardiac intensive care unit. Implantable cardioverter defibrillator (ICD) interrogation showed 38 shocks delivered over the prior two-week period. Coronary angiography showed no obstructive coronary disease and an intraaortic balloon pump (IABP) was placed for cardiogenic shock. He was intubated and sedated on fentanyl and propofol. He continued to have episodes of VT despite treatment with lidocaine, procainamide, and amiodarone drips. Further trials of paralysis and left stellate ganglion nerve block did not suppress his VT. Since the patient was refractory to all prior interventions, was deemed too unstable for VT ablation, and had a prolonged anticipated wait time for heart transplant, he underwent TAH placement as a bridge to heart transplant. He recovered well and eventually underwent successful heart transplant. Discussion: Management of electrical storm requires a stepwise approach including administration of antiarrhythmics, sedation, mechanical hemodynamic support, and catheter ablation. Our patient had incessant VT despite exhaustive medical and supportive therapies, but was too unstable to undergo VT ablation. In cases of refractory VT storm, definitive treatment with heart transplantation must be considered, but bridging patients to transplant poses a challenge. Our patient underwent TAH placement and was successfully stabilized prior to transplant. In centers with this capability, TAH should be recognized as a legitimate option in the pathway for VT, particularly with a long anticipated wait time for heart transplant.

Abstract 11404: Phenotyping Cardiac Sarcoidosis With PET/MR: Imaging Characteristics, Treatment Response, and Outcomes of Isolated Cardiac Sarcoidosis versus Extra-Cardiac Sarcoidosis With Cardiac Involvement

Introduction: Diagnosing cardiac sarcoidosis (CS) remains challenging due to limitations of available clinical criteria and low yield of endomyocardial biopsy. PET-MR imaging allows for multidimensional non-invasive assessment of suspected CS. However, the true diagnostic and prognostic impact of these modalities require further exploration. Hypothesis: PET-MR can phenotype CS and its associated treatment response. Methods: We identified 100 patients with known or suspected CS (52±1.8 years, 66% male) who underwent PET-MR imaging: 38 individuals with isolated CS (ICS) (50±1.8 years, 65% male) and 62 subjects with CS and biopsy-proven extra-cardiac sarcoidosis (ECS) (52±2.4 years, 66% male). A subset of 56 patients (24 ICS and 32 ECS) was classified as the phenotype cohort if they were: 1) treatment naïve, 2) started on immunosuppressant treatment after PET, and 3) had follow up PET to assess treatment response, which was graded as complete (CTR), partial (PTR), and no response (NR). PET-MR phenotype was graded as combined imaging findings suggestive of CS (Figure 1A), equivocal for CS, and not suggestive of CS. Major adverse cardiovascular events (MACE) were defined as sustained ventricular tachycardia, ventricular fibrillation, heart transplantation and/or cardiac death at 1 year. Results: From the ICS phenotype cohort, PET-MR findings suggestive of CS were present in 100% (8/8) of patients with biopsy-proven ICS vs. 56% (9/16) of subjects without biopsy (P=0.03). CTR/PTR rates were overall higher in ECS compared to ICS (81% vs. 58%; P=0.06), and in patients with PET-MR suggestive of CS (P=0.01; Figure 1B), in both the ECS (P=0.04) and ICS (P=0.08) groups. MACE events were significantly greater in ICS vs ECS (HR 3.9 [1.6 - 9.7]; P=0.003), and in patients with PET-MR suggestive of CS (HR 8.2 [1.1 - 62]; P=0.04; Figure 1C). Conclusion: PET-MR can identify phenotypes of CS which have distinct disease manifestations, treatment response rates, and clinical outcomes.

Physical activity and heart failure: a forgotten indicator

Abstract Introduction Low physical activity may be associated with comorbidities, sedentary lifestyle or clinical worsening in heart failure (HF) patients. Cardiovascular implantable electronic devices (CIEDs) detect and analyse physical activity data that is often integrated in multifactorial algorithms for predicting HF decompensations, but its potential is probably underestimated. Purpose We hypothesized that low physical-activity levels, obtained from remote monitoring of CIEDs, help predict clinical outcomes in HF patients, independently from multifactorial algorithms. Methods We retrospectively evaluated consecutive patients with HF and CIEDs through clinical assessments and remote monitoring (two monitoring systems were used). Low activity was defined as &amp;lt;1 hour/day of physical activity and two groups of patients were defined: patients with low activity alerts (group 1) and patients without low activity alerts (group 2). Primary outcome was defined as death by all causes and secondary outcome as HF hospitalizations and sustained ventricular tachycardia (VT) or ventricular fibrillation (VF) episodes. Results From 121 patients with RPM, physical activity data was obtained in 104 (85,9%). Mean age was 63,98±12,44 years, 70,2% were males and follow-up was 59,19±38,491 months. Fifty-four (51,9%) had implantable cardiac resynchronization therapy (CRT) defibrillator (CRT-D), 46 (44,2%) transvenous implantable cardioverter defibrillator (ICD), and 4 (3,8%) CRT pacemaker (CRT-P). The aetiology was idiopathic in 42,5% and ischemic in 40,2%. Mean left ventricular ejection fraction was 34,08±11,40% and mean physical activity duration was 2,25±1,84 hours/day. Forty-eight (53,7%) had low activity alerts (group 1) and 56 (46,3%) had no low activity alerts (group 2). In group 1 mean period of low activity was 52,978±15,75 days/year. Patients from group 1 were older (p=0,001), had more oncological disease (p=0,041) and peripheral artery disease (p=0,028). Three deaths occurred in total, all in group 1 (p=0,039) and HF hospitalizations were more frequent in group 1 (1,68±2,59 vs 0,69±1,32, p=0,005). Low activity burden was also associated with atrial fibrillation burden (r=0,473, p&amp;lt;0,05) and number of episodes of VT or VF (r=0,267, p=0,007). A decrease of 50% or more in mean duration of physical activity, but above 1 hour/day, was associated with increase HF hospitalizations (1,83±2,13 vs 1,05±1,95, p=0,006). Conclusion Low physical activity data obtained from CIEDs was associated with HF hospitalizations, arrhythmic events and death by all causes, independently of multifactorial algorithms. A decrease in basal activity even above alert threshold, was associated with HF hospitalizations and may be an even earlier sign of HF decompensations. Funding Acknowledgement Type of funding sources: None.

Lower rate limit in cardiac resynchronization therapy defibrillators

Abstract Background There is few data about programmed lower rate limit (LRL) in real world heart failure (HF) patients with cardiac resynchronization therapy–defibrillators (CRT-Ds) and its influence in clinical outcomes. Heart rate score (HRS) is the percentage of all atrial-paced and sensed events in the single tallest 10 beats/min device histogram bin and may indicate impaired heart rate variability. Purpose We hypothesized that higher LRL programming is associated with worse clinical outcomes as arrhythmic events and HF decompensations in chronic HF patients with CRT-Ds. Methods LRL was evaluated and HRS was calculated from remote monitoring in 126 HF patients with CRT-D. Primary outcome was defined as HF hospitalizations and related admissions to the emergency department and secondary outcome as number of device therapies, sustained ventricular tachycardia (VT) and ventricular fibrillation (VF). Results Mean age was 69,03±10,39 years, 81 (64,3%) were males and mean follow-up was 53,72±46,13 months. Mean left ventricular ejection fraction was 30,31±8,33% and 29 (23,0%) were in NYHA III–IV. HF aetiology was idiopathic in 39 (43,3%), ischemic in 32 (25,4%) and alcoholic cardiomyopathy in 8 (6,3%). Thirty-seven (29,4%) patients had atrial fibrillation and 33 (26,2%) coronary disease. LRL ranged from to 40 to 80 bpm and mean LRL was 52,64±9,64 and mean HRS 49,60±23,17%. Programmed LRL was higher in women (p=0,014), patients with atrial fibrillation (AF) (p=0,012) and coronary disease (p=0,015). Higher LRL correlated with HF hospitalizations and related admissions to the emergency department (ED) (r=0,541, p=0,001), VT or VF episodes (r=0,337, p=0,005) and CRT-D number of therapies (r=0,342, p=0,004) and higher HRS (r=0,547, p&amp;lt;0,05). Conclusion Higher LRL programming was associated with higher HRS, HF decompensations with hospitalization or admission to the emergency department, VT or VF episodes and CRT-D therapies in a real world population. More studies are required but lower LRL may be preferred in HF patients. Funding Acknowledgement Type of funding sources: None.

Exercise-induced ventricular arrythmia in asymptomatic patients with Mitral Valve Prolapse

Abstract Introduction Mitral Valve Prolapse (MVP) is associated with complex ventricular arrythmia (VA) and sudden cardiac death but risk stratification remains unclear. Exercise induces an hyperadrenergic state and could trigger VA, however, data on exercise-induced VA (EIVA) in MVP patients are scarce. Objective To describe EIVA prevalence, origin, characteristics and associated features in MVP patients. Methods In this observational prospective study, 64 MVP asymptomatic patients (58±14 years, 41 men) with mild to severe mitral regurgitation (MR) and without left ventricular (LV) dysfunction, underwent echocardiography and symptom-limited exercise testing. Continuous 12-lead ECG monitoring was performed throughout testing. Severe EIVA was defined as ventricular triplets, sustained or non-sustained ventricular tachycardia (NSVT) or ventricular fibrillation. Results All patients exercised at maximal intensity until exhaustion. EIVA was observed in 54 (84%) subjects including 12 (19%) patients with severe EIVA (7 triplets, 5 NSVT). Severe EIVA originated mainly from the mitral apparatus (all but one) and occurred at high exercise intensity (median 90% of predicted workload) or during early recovery phase. Compared to the rest of the cohort the patients with severe EIVA had similar resting ECG characteristics, similar LV dimension and function, similar degree of MR and mitral apparatus morphology. Finally, severe EIVA was not associated with an alteration of exercise tolerance. Conclusion Exercise frequently unmasks ventricular arrythmia in patients with MVP. EIVA appears not linked to MVP features nor to exercise tolerance and seems to provide additional phenotyping information that could be linked to prognosis. Funding Acknowledgement Type of funding sources: None.

The peri-infarct gray zone of myocardial fibrosis is a better predictor of ventricular arrhythmias than dense core fibrosis in patients with previous myocardial infarction

Abstract Background Current sudden cardiac death (SCD) risk stratification relies heavily on left ventricular ejection fraction (LVEF), but markers to refine risk assessment are needed. Dense core fibrosis (DCF) and peri-infarct “gray zone” of myocardial fibrosis (GZF) on late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) have been proposed as potential arrhythmogenic substrates. The aim of our study was to determine whether DCF and GZF could predict the occurrence of ventricular arrhythmias in patients with previous myocardial infarction. Methods We performed a single centre retrospective study enrolling consecutive patients with previous myocardial infarction undergoing CMR before implantable cardioverter-defibrillator (ICD) implantation. Areas of LGE were subdivided into “core” DCF and “peri-infarct” GZF zones based on signal intensity (&amp;gt;5 SD, and 2–5 SD above the mean of reference myocardium, respectively). The primary endpoint was a composite of sudden arrhythmic death, appropriate ICD shock, ventricular fibrillation (VF), or sustained ventricular tachycardia (VT) as detected by the device. Results A total of 88 patients (median age 61 years [IQR 54–73], 84% male, median LVEF 30% [IQR 23–36%], 14% secondary prevention) were included. During a median follow-up of 23 months [IQR 9–38], 13 patients reached the primary endpoint (10 appropriate ICD shock, 2 sustained VT or VF, and 1 sudden arrhythmic death). Patients who attained the primary endpoint had similar DCF (30.4±14.7 g vs. 28.0±15.3 g; P=0.601) but a greater amount of GZF (18.1±9.6 g vs. 11.9±6.7 g; P=0.005). On univariate analysis, GZF was associated with the composite endpoint (HR: 1.09 per gram; 95% CI: 1.02–1.15; P=0.006), whereas DCF was not (HR: 1.01 per gram; 95% CI: 0.98–1.05; P=0.571). After adjustment for LVEF, GZF remained independently associated with the primary endpoint (adjusted HR: 1.06 per gram; 95% CI: 1.01–1.12; P=0.035). Decision tree analysis identified 11.9g of GZF as the best cut-off to predict life-threatening arrhythmic events. The primary endpoint occurred in 11 out of the 35 patients (31.4%) with GZF ≥11.9 g, but in only 2 of the 53 patients (3.8%) with GZF &amp;lt;11.9 g – Figure 1. Conclusions The extent of peri-infarct GZF seems to be a better predictor of ventricular arrhythmias than DCF. This parameter may be useful to identify a subgroup of patients with previous myocardial infarction at increased risk of life-threatening arrhythmic events. Funding Acknowledgement Type of funding sources: None.

High prevalence of malignant ventricular arrhythmias in patients with early-stage left ventricular noncompaction

Abstract Background Early-stage left ventricular non compaction (LVNC) is a nonischemic cardiomyopathy characterized with nondilated phenotype and unpredictable risk of malignant ventricular arrhythmias (MVA). Purpose To report the occurrence of MVA in patients with early-stage LVNC. Methods Consecutive patients (n=63) diagnosed with LVNC according to recognized criteria either on transthoracic echocardiogram or cardiac magnetic resonance were retrospectively enrolled. Patients with late-stage LVNC, defined by a coexistent dilated cardiomyopathy phenotype, were excluded (n=49). Patient-tailored medical treatment, as well as ICD implantation strategies, were based on the updated ESC guidelines integrated by the experience of a referral center for arrhythmia management. The study endpoint was the occurrence of MVA (defined as sustained VT, VF, or appropriate ICD therapy) by 5-year follow-up. Results The study cohort consisted of 14 patients (mean age 37±17 y, 64% males), presenting with palpitation (n=4), syncope (n=4), or dyspnea on effort (n=6). LVNC was diagnosed by echocardiogram and cardiac magnetic resonance in 13 and 1 patients, respectively. Because of nonmalignant VA, seven patients (50%) underwent ICD implant before discharge. By 5-year follow-up, 5 patients (36%) experienced MVA, including VF or appropriate ICD shocks for fast VT. Left ventricular ejection fraction (LVEF) ≥45% was the only factor associated with the occurrence of MVA (5/11 event in cases with LVEF ≥45% vs. 0/3 events in controls with LVEF &amp;lt;45%; p=0.145). Baseline features, including age, gender, NC/C ratio, and clinical presentation were comparable between cases with LVEF ≥45% and controls, all p&amp;gt;0.05. Drug treatment, including RAAS inhibitors, betablockers and antiarrhythmics was also comparable. Conclusions Our preliminary data show that in early-stage LVNC the occurrence of MVA is higher for patients with LVEF ≥45%. Efforts are needed to identify earlier predictors of arrhythmic risk, to improve patient selection for ICD implant. Funding Acknowledgement Type of funding sources: None.

Ventricular Arrhythmias in Patients Undergoing Primary Percutaneous Coronary Intervention (PCI) for ST-Segment Elevation Myocardial Infarction (STEMI)

Objective: To determine the frequency of ventricular arrhythmias in patients undergoing primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI) at a tertiary care hospital in Karachi, Pakistan. Material and Methods: This descriptive case series study was done at the National Institute of Cardiovascular Disease, Karachi. All patients of either gender having an age between 18 and 70 years of diagnosis with STEMI undergoing primary PCI were included. All the patients were kept under observation for 72 hours in the hospital, and ventricular arrhythmias such as Accelerated Idioventricular Rhythm (AIVR), Frequent PVCs (premature ventricular contractions), Non-Sustained Ventricular Tachycardia, Sustained Ventricular Tachycardia, and Ventricular Fibrillation were recorded. Results: The mean age of the patients was 54.72 ±10.75 years. The majority of the patients, 75.2%, were males and 24.8% were females. The frequency of ventricular arrhythmia was found in 89 (25.9%) of the patients. Among 89 patients with ventricular arrythmia, AIVR was found in 30 (33.71%), frequent PVCs in 18 (20.22%), non-sustained ventricular tachycardia in 23 (25.84%), sustained ventricular tachycardia and ventricular fibrillation in 9 (10.11%) each. Conclusion: As per the study conclusion, the ventricular arrhythmias was observed to be considerably higher among patients undergoing primary PCI for ST-STEMI. Keywords: Ventricular arrhythmias, PCI, ST-segment elevation MI

In-hospital arrhythmic burden reduction in diabetic patients with acute myocardial infarction treated with SGLT2-inhibitors: Insights from the SGLT2-I AMI PROTECT study.

BackgroundSodium-glucose co-transporter 2 inhibitors (SGLT2-i) have shown significant cardiovascular benefits in patients with and without type 2 diabetes mellitus (T2DM). They have also gained interest for their potential anti-arrhythmic role and their ability to reduce the occurrence of atrial fibrillation (AF) and ventricular arrhythmias (VAs) in T2DM and heart failure patients.ObjectivesTo investigate in-hospital new-onset cardiac arrhythmias in a cohort of T2DM patients presenting with acute myocardial infarction (AMI) treated with SGLT2-i vs. other oral anti-diabetic agents (non-SGLT2-i users).MethodsPatients from the SGLT2-I AMI PROTECT registry (NCT05261867) were stratified according to the use of SGLT2-i before admission for AMI, divided into SGLT2-i users vs. non-SGLT2-i users. In-hospital outcomes included the occurrence of in-hospital new-onset cardiac arrhythmias (NOCAs), defined as a composite of new-onset AF and sustained new-onset ventricular tachycardia (VT) and/or ventricular fibrillation (VF) during hospitalization.ResultsThe study population comprised 646 AMI patients categorized into SGLT2-i users (111 patients) and non-SGLT2-i users (535 patients). SGLT2-i users had a lower rate of NOCAs compared with non-SGLT2-i users (6.3 vs. 15.7%, p = 0.010). Moreover, SGLT2-i was associated with a lower rate of AF and VT/VF considered individually (p = 0.032). In the multivariate logistic regression model, after adjusting for all confounding factors, the use of SGLT2-i was identified as an independent predictor of the lower occurrence of NOCAs (OR = 0.35; 95%CI 0.14–0.86; p = 0.022). At multinomial logistic regression, after adjusting for potential confounders, SGLT2-i therapy remained an independent predictor of VT/VF occurrence (OR = 0.20; 95%CI 0.04–0.97; p = 0.046) but not of AF occurrence.ConclusionsIn T2DM patients, the use of SGLT2-i was associated with a lower risk of new-onset arrhythmic events during hospitalization for AMI. In particular, the primary effect was expressed in the reduction of VAs. These findings emphasize the cardioprotective effects of SGLT2-i in the setting of AMI beyond glycemic control.Trial registrationData are part of the observational international registry: SGLT2-I AMI PROTECT. ClinicalTrials.gov, identifier: NCT05261867.

Geomagnetic Disturbances and Ventricular Arrhythmia in Patients with Implantable Cardioverter Defibrillators from a US-Based Hospital

Background and Aim: Episodes of ventricular arrhythmias (VA) have been associated with environmental exposures such as air pollution. Solar driven geomagnetic disturbances may alter autonomic nervous system activity, modify systemic oxidative stress, or induce changes in aerosols. However, few studies have investigated if there is an association between VA and geomagnetic disturbances (GMD). The aim of this study was to assess whether GMD is associated with the initiation of VA in patients with implantable cardioverter defibrillators (ICDs). Methods: This study examined the association between GMD driven by solar activity on VA, defined as sustained and non-sustained ventricular fibrillation or ventricular tachycardia, in patients with ICDs using a time-stratified case-crossover analysis between September 2006 and March 2010 from Tufts Medical Center’s Cardiac Arrythmia Center in Boston, MA. Patients were identified from a single Massachusetts-based Medical Center and VAs were identified from retrieved ICD records as part of routine care. We considered several pollutants such as PM2.5, black carbon (BC), O3, NO2 and ultrafine particles (PN) in our analyses using time lags prior to the event. Daily GMD information was appended for the week previous to each event and matched control day. Results: During the study period, 91 patients had a total of 1,050 VA. During periods of increased GMD, patients with low ejection fraction and a history of a MI or coronary intervention had increased odds of VA , with patients who had a coronary bypass graph being the highest (OR: 1.63, 95% CI 1.05, 2.52 ). Conclusions: Among patients with ICDs, exposure to GMD was associated with higher odds of VA in those with pre-existing heart disease and/or a history of coronary interventions. GMD driven by solar activity has the potential to affect heart health in patients with cardiac comorbidities. Keywords: Solar activity, geomagnetic disturbances, implantable cardioverter defibrillator, ventricular arrhythmia

PRE-OPerative ECHOcardiograhy for prevention of cardiovascular events after non-cardiac surgery in intermediate- and high-risk patients: protocol for a low-interventional, mixed-cohort prospective study design (PREOP-ECHO)

BackgroundCardiac evaluation using transthoracic echocardiography before noncardiac surgery is common in real-world practice. However, evidence supporting preoperative echocardiography is lacking. This study aims to evaluate the additional benefit of preoperative echocardiography in predicting postoperative cardiovascular events (CVE) in noncardiac surgery.MethodsThis study is designed as a multicenter, prospective study to assess the utility of preoperative echocardiography in patients undergoing intermediate- or high-risk noncardiac surgery. This trial comprises two studies: (1) a randomized controlled trial (RCT) for patients undergoing intermediate-risk surgery with fewer than three clinical risk factors from the revised cardiac risk index (intermediate-risk group) and (2) a prospective cohort study for patients undergoing intermediate-risk surgery with three or more clinical risk factors, or who undergo high-risk surgery regardless of the number of clinical risk factors (high-risk group). We hypothesize that the use of preoperative echocardiography will reduce postoperative CVEs in patients undergoing intermediate- to high-risk surgery through discovery of and further intervention for unexpected cardiac abnormalities before elective surgery. A total of 2330 and 2184 patients will be enrolled in the two studies. The primary endpoint is a composite of all-cause death; aborted sudden cardiac arrest; type I acute myocardial infarction; clinically diagnosed unstable angina; stress-induced cardiomyopathy; lethal arrhythmia, such as sustained ventricular tachycardia or ventricular fibrillation; and/or newly diagnosed or acutely decompensated heart failure within 30 days after surgery.DiscussionThis study will be the first large-scale prospective study examining the benefit of preoperative echocardiography in predicting postoperative CVE. The PREOP-ECHO trial will help doctors identify patients at risk of postoperative CVE using echocardiography and thereby reduce postoperative CVEs.Trial registrationThe Clinical Research Information Service KCT0006279 for RCT and KCT0006280 for prospective cohort study. Registered on June 21, 2021.