Frequent Ventricular Tachycardia Research Articles

ACUTE MYOCARDIAL INJURY IN A PATIENT WITH TYPE–1 NEUROFIBROMATOSIS: A CASE OF SUSPECTED PHEOCROMOCYTOMA–ASSOCIATED MYOCARDITIS

Abstract A 54–year–old patient with an history of type–1 neurofibromatosis presented to the emergency department (ED) due to recurrent abdominal pain with diarrhea. Clinical examination didn’t show anything remarkable. She was mildly hypertensive, apyretic. During her staying in the ED, she complained about chest pain and an electrocardiogram (ECG) was performed. ECG showed sinus rhythm, normal heart rate, left ventricular (LV) hypertrophy with marked horizontal ST segment depression in the precordial leads and bimorphic ventricular ectopic beats with prevalent right bundle branch block superior axis morphology, likely from the medio–basal inferior LV. Troponin T (peak 958 ng/L, normal <15 ng/L) and NTproBNP (peak 2357 ng/L, normal <180 ng/L) were elevated, hemoglobin, creatinine and liver function were normal, C–reactive protein peaked at 120 mg/dL. Echocardiogram showed mildly reduced left ventricular ejection fraction (LVEF) with inferior and inferolateral hypokinesia and moderate mitral regurgitation (MR). She was admitted to cardiac intensive care unit with the suspected diagnosis of an acute coronary syndrome and was started on acetylsalicylic acid, metoprolol, furosemide and potassium canrenoate. Amiodarone was added due to frequent ventricular tachycardias. Due to the symptoms and the history of neurofibromatosis a whole body computed tomography (CT) was done. CT showed a 53 mm mass on the left adrenal gland with intense enhancement, suspected for a neoplastic origin (Figure 2). Plasmatic and urinary cathecolamines and metanephrines were increased. Positron–emission tomography (PET)/CT with 68Ga showed left adrenal uptake, compatible with a neuroendocrine tumor. Coronary arteriography showed normal coronary arteries. The patient underwent a cardiac magnetic resonance (CMR) study in the suspect of acute myocarditis. CMR showed normal biventricular function, an inferior basal hypokinesia with focal intramyocardial late gadolinium enhancement (LGE) suspected for a post–inflammatory origin and mild pericardial effusion. After pharmacological preparation a laparoscopic left adrenalectomy was performed, and histology confirmed the diagnosis of a composite pheocromocytoma. Three months after, the patient was asymptomatic, biochemistry showed normalization of both troponin T and endocrinological biomarkers, the echocardiogram showed preserved LVEF without areas of hypokinesia and mild MR. A follow–up CMR at six months from the acute injury has been scheduled.

High-sensitivity Cardiac Troponin T Is a Useful Biomarker for Predicting the Prognosis of Patients with Systemic Sarcoidosis Regardless of Cardiac Involvement.

Objective Cardiac involvement defines the prognosis for patients with systemic sarcoidosis. Despite advancements in techniques for diagnosing cardiac lesions, there remains significant room for improvement in cardiac screening and prognostic prediction. The present study therefore assessed the prognostic factors associated with cardiovascular events in patients with sarcoidosis. Methods We retrospectively studied 132 patients with systemic sarcoidosis and evaluated the clinical data obtained between 2009 and 2022. A Kaplan-Meier survival analysis and Cox proportional hazards models were used to evaluate the associations between cardiovascular events and prognostic factors. Results The median age of the patients at the diagnosis was 64.0 (55.0-71.0) years old. During a mean follow-up period of 6.3±3.2 years, 28 patients suffered from cardiovascular events. Patients in the event group had more severe heart failure symptoms, more frequent ventricular tachycardia, higher serum high-sensitivity cardiac troponin T (hs-cTnT) values [0.025 (0.017-0.044) vs. 0.011 (0.007-0.019) ng/mL, p<0.001], and lower left ventricular ejection fraction values than those in the non-event group. These trends were observed even if the patients were not diagnosed with cardiac involvement at the time of enrollment. A multivariate analysis revealed that hs-cTnT was an independent biomarker for the prediction of cardiac events (hs-cTnT >0.014 ng/mL: HR: 7.31, 95% confidence interval: 2.20 to 24.28, p<0.001). Conclusion Hs-cTnT is a useful biomarker for predicting cardiovascular events in patients with sarcoidosis, even if cardiac involvement is not detected at the initial evaluation.

PO-05-145 A CASE OF SUSPECTED CARDIAC SARCOIDOSIS MIMICKING ISCHEMIC CARDIOMYOPATHY

Cardiac sarcoidosis (CS) is challenging due to varied clinical presentation and limited accuracy of diagnostic criteria. We describe a case of suspected CS in a patient with ischemic cardiomyopathy (ICM) presenting in ventricular tachycardia (VT) storm. To describe the presentation of suspected CS in a patient with ICM and VT. N/A A 73 year old male with ICM and ejection fraction of 35% initially presented with myocardial infarct requiring 3-vessel coronary artery bypass surgery. Months later he developed sustained monomorphic VT which was detected on his pacemaker and underwent upgrade to a dual chamber implantable cardioverter defibrillator. He continued to have frequent VT ultimately presenting in VT storm. He was loaded on amiodarone and referred for radiofrequency catheter ablation. During index ablation, the left ventricular (LV) endocardial bipolar voltage was normal, which was inconsistent with the inferobasal and basal septal scar identified on pre procedural cardiac computed topography (CT) (Figure 1). The clinical VT was mapped to the anterior interventricular vein and targeted from the LV summit since proximity of AIV to the left anterior descending artery precluded ablation from the AIV. His arrhythmic presentation and LV dysfunction was disproportionate to degree of coronary disease. In addition, discordance between clinical VT origin site, bipolar endocardial voltage, and scar on cardiac CT prompted suspicion of an alternate underlying diagnosis, such as an arrhythmogenic inflammatory cardiomyopathy. A positron emission tomography/computed tomography (PET/CT) later obtained showed evidence of patchy 18F-fluorodeoxyglucose uptake along the inferolateral LV, suggestive of CS. He was started on immunosuppressants but developed recurrent VT despite anti arrhythmic therapy and required 2 subsequent ablations. He has since remained quiescent from a VT standpoint on amiodarone with plans for alcohol septal ablation or stereotactic body radiation therapy if VT recurs. Symptoms have improved with steroids and immunosuppressants with no inflammation detected on most recent PET/CT High suspicion of CS should remain in patients presenting with significant arrhythmic burden. Normal endocardial voltage during VT ablation can be suggestive of an acute inflammatory process and should prompt consideration of CS, especially in cases with discordant areas of scar and wall thinning on imaging.

Surgical Ablation of Ventricular Tachycardia.

Surgery for ventricular tachycardia (VT) is indicated in patients in whom pharmacotherapy or catheter ablation is ineffective or frequent VT attacks are not suppressed or with frequent activation of implantable cardioverter defibrillator. In ischemic VT, resection of fibrous endocardium combined with encircling cryothermia at the border between the infarcted and normal myocardium is performed. In surgery for VT associated with cardiomyopathy, close collaboration between the physician and surgeon is important and intraoperative mapping using electro-anatomic mapping system is helpful. In VT associated with cardiac tumors, cryothermia of the thinned subepicardial myocardium at the edge of the tumor is recommended in addition to resection of tumors.

Abstract 11573: Refractory Ventricular Tachyardia Storm: Treatment With Sympathetic Denervation in Patient With Non-Ischemic Cardiomyopathy

Introduction: Ventricular tachycardia (VT) is a potentially life-threatening arrhythmia commonly present in cardiomyopathy. Implantable cardioverter-defibrillator (ICD) placement can decrease mortality in patients with VT. However, when an ICD shocks it can cause direct myocardial injury, contraction band necrosis, fibrosis, and significant morbidity. Antiarrhythmic medications and catheter ablation can decrease arrhythmia burden and ICD shocks. Cardiac sympathetic denervation has been effective in a few refractory cases, but prospective data is scarce, especially in non-ischemic cardiomyopathy. Case description We present the case of a 59-year-old gentleman with a past medical history of hypertension, diabetes, hypothyroidism, atrial fibrillation, and non-ischemic cardiomyopathy, who presented to the hospital with recurrent ICD shocks. The patient had an ICD placed due to an episode of non-sustained VT resulting in presyncope. The patient had an arrhythmia-free period of 10 years followed by frequent VT. He was managed in the outpatient setting with amiodarone, dofetilide, and mexiletine which did not suppress his arrhythmia burden. Cardiac MRI showed multi-segment transmural late gadolinium enhancement consistent with a non-ischemic pattern. He underwent three endocardial and epicardial ablations over eight months before this admission. He was started on amiodarone and lidocaine infusions. With his history of recurrent VT despite multiple ablations, the patient underwent bilateral thoracoscopic sympathetic denervation. He was discharged from the hospital six days post-op without any episodes of VT. His latest ICD check which was ten months post-operatively did not show any VT or VT-induced ICD shock. Conclusion VT storm may be associated with a catecholaminergic surge and be refractory to traditional therapy. Due to this, sympathetic denervation is a viable option to prevent morbidity of frequent defibrillator therapy. This case highlights the utility of sympathetic denervation as a treatment of refractory ventricular arrhythmias in non-ischemic cardiomyopathy.

Bipolar ablation of refractory ventricular arrhythmias using a novel dedicated adapter. A multicenter study

Abstract Background Bipolar ablation (BA) recently emerged as an alternative for treatment of ventricular tachycardia (VT) and premature ventricular contractions (PVC) refractory to a classic unipolar ablation (UA). Data on the use of available BA systems is lacking. Purpose To determine feasibility, safety and efficacy of a novel BA adapter in consecutive patients with refractory VT/PVC undergoing repeat ablations. Methods The study group consisted of consecutive patients with VT/PVC after failure of at least one standard UA who underwent redo procedures performed with a support of BA at six European centers. A second ablation catheter was connected in the position of a return electrode using a novel BA adapter. Results Between March 2021 and March 2022 a total number of 19 patients after failed ablation attempts underwent redo procedure using a novel BA adapter (17 males, age 61±11, number of prior ablation attempts 2,5±1,6; range 1–7). The main indication for redo ablation was recurrence of frequent PVC (n=10), VT (n=8) or electrical storm (n=1). Fifteen patients underwent combined UA+BA procedure during redo ablation, whereas 4 remaining patients underwent BA only. Two patients required epicardial access. Mean procedural time was 157±77 minutes. The mean BA time was 367±245s (power 32±9W) and mean UA time was 349±290s (power 43±6W). Apart from 1 anticipated AV block there were no major complications. Minor complications included char formation at 8mm tip electrode and steam pop without sequalae in one VT patient. BA+UA led to acute elimination of clinical PVC/VT in 18 patients. In the remaining 1 patient no effect on clinical VT during UA+BA was observed. The follow up lasted 4±3 months. Six (75%) VT patients remained arrhythmia-free and significant PVC burden reduction was achieved in nine (90%) PVC patients during follow-up. One patient treated for electrical storm experienced a single VT episode after 11 months. One patient after initially failed UA+BA underwent successful bipolar reablation after 2 months. Conclusions Bipolar ablation of refractory ventricular arrhythmias using a novel dedicated adapter is feasible, seems safe and effective. These encouraging preliminary results need to be confirmed in properly designed prospective trials. Funding Acknowledgement Type of funding sources: None.

An automated near-real time computational method for induction and treatment of scar-related ventricular tachycardias.

Catheter ablation is currently the only curative treatment for scar-related ventricular tachycardias (VTs). However, not only are ablation procedures long, with relatively high risk, but success rates are punitively low, with frequent VT recurrence. Personalized in-silico approaches have the opportunity to address these limitations. However, state-of-the-art reaction diffusion (R-D) simulations of VT induction and subsequent circuits used for in-silico ablation target identification require long execution times, along with vast computational resources, which are incompatible with the clinical workflow. Here, we present the Virtual Induction and Treatment of Arrhythmias (VITA), a novel, rapid and fully automated computational approach that uses reaction-Eikonal methodology to induce VT and identify subsequent ablation targets. The rationale for VITA is based on finding isosurfaces associated with an activation wavefront that splits in the ventricles due to the presence of an isolated isthmus of conduction within the scar; once identified, each isthmus may be assessed for their vulnerability to sustain a reentrant circuit, and the corresponding exit site automatically identified for potential ablation targeting. VITA was tested on a virtual cohort of 7 post-infarcted porcine hearts and the results compared to R-D simulations. Using only a standard desktop machine, VITA could detect all scar-related VTs, simulating activation time maps and ECGs (for clinical comparison) as well as computing ablation targets in 48 minutes. The comparable VTs probed by the R-D simulations took 68.5 hours on 256 cores of high-performance computing infrastructure. The set of lesions computed by VITA was shown to render the ventricular model VT-free. VITA could be used in near real-time as a complementary modality aiding in clinical decision-making in the treatment of post-infarction VTs.

Catheter Ablation of Ventricular Tachycardia Originating from Congenital Left Ventricular Diverticula

Patients with congenital ventricular aneurysms or diverticula can have ventricular arrhythmias. A 23-year-old woman with congenital diverticula was diagnosed with frequent premature ventricular complexes and ventricular tachycardia and was scheduled for catheter ablation. Detailed endocardial mapping was performed using intracardiac echocardiography integrated with three-dimensional computed tomography and the three-dimensional mapping system. Epicardial mapping was also performed using the three-dimensional mapping system. A large area of low voltage was identified inside the diverticula. At the ostium of the diverticula, fragmented and late potentials of low amplitude were identified during sinus rhythm on endocardial mapping. The late potential during sinus rhythm was earlier than the onset of the premature ventricular complex. Endocardial catheter ablation of these sites was acutely successful, and no premature ventricular complexes and ventricular tachycardia occurred during follow-up.

Ventricular fibrillation arrest after blunt chest trauma in a 33-year-old man, commotio cordis?

BackgroundCommotio cordis is an event in which a blunt, non-penetrating blow to the chest occurs, triggering a life-threatening arrhythmia and often sudden death. This phenomenon is often seen in young, male athletes and has become increasingly well-known over the past few decades. We present a unique case in which ventricular fibrillation occurs in an older male athlete after blunt trauma.Case presentationPatient with no known medical history was brought to the ER after being found unconscious after a soccer ball kick to the chest. He was found to be in ventricular fibrillation and successfully resuscitated on the soccer field. Patient was admitted to the hospital and lab workup and initial imaging were unremarkable, except elevated troponin and lactate, which returned to normal levels. An echocardiogram showed global left ventricular systolic dysfunction with a visually estimated ejection fraction of 45–50%. Coronary showed angiographically nonobstructive coronary arteries. The patient was diagnosed with commotio cordis and discharged from the hospital in stable condition. Follow-up echocardiogram continued to show low ejection fraction and event monitor demonstrated frequent polymorphic ventricular tachycardia with periods of asystole.ConclusionThis case is unique in that blunt trauma to the chest from a soccer ball immediately triggered ventricular fibrillation in a patient with a possible cardiomyopathy. It is possible that the blunt trauma caused primary commotio cordis that led to cardiomyopathy in a previous healthy man, or that an underlying cardiomyopathy made it more likely for this to occur. Overall, increased awareness and prevention efforts of blunt chest trauma are required to reduce the high mortality associated life-threatening arrhythmias. There is limited data regarding the interplay between these two entities.

Catheter ablation of sustained idiopathic right ventricular outflow tract tachycardia in a pregnant patient without fluoroscopy

In 2020, our department has performed 739 operations on nonpregnant patients. Additionally, 545 highly successful nonfluoroscopic catheter ablation of cardiac arrhythmias were routinely performed using a three-dimensional navigation system, including 47 patients with idiopathic ventricular tachycardia (VT) from the right ventricular outflow tract (RVOT).&#x0D; A 38-year-old female patient with a structurally normal heart was admitted to our hospital in 1011 weeks of her third pregnancy because she sustained recurrent 166 regular heartbeats per minute, wide QRS-complex tachycardia with left bundle branch morphology, and frequent premature ventricular contractions on Holter monitoring with complaints of presyncope and dyspnea. Standard antiarrhythmic drugs failed to control tachycardia. This case report presents our initial successful experience of the rescue zero-fluoroscopy catheter ablation of sustained poorly tolerated idiopathic RVOT tachycardia in a pregnant patient. Our result suggests that this technique may be considered in the few rare cases in which drug-resistant, sustained frequent VT is accompanied by hemodynamic compromise with fluoroscopy contraindication.&#x0D; AIM: Diagnostic algorithm of idiopathic sustained drug-resistant, poorly tolerated VT and the possibility of radiofrequency catheter ablation in the most vulnerable first trimester of pregnancy without fluoroscopy were presented in our case report.

Three-year chronic follow-up from the pilot study of a substernal extravascular implantable cardioverter defibrillator

Abstract Funding Acknowledgements Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Medtronic Background The investigational Extravascular Implantable Cardioverter-Defibrillator (EV ICD) uses a substernal lead and delivers defibrillation and pacing therapies, including antitachycardia pacing (ATP). Objective To characterize EV ICD system performance through 3 years. Methods The prospective, first-in-human EV ICD Pilot study was conducted at 4 sites in Australia and New Zealand. ICD-indicated patients were enrolled July-December of 2018. Defibrillation testing was conducted for all patients at implant, and chronically per physician discretion. Electrical testing was conducted at pre-hospital discharge, 2 weeks, 4-6 weeks and 3 months post-implant, and every 6 months thereafter. Posture effects on pacing and sensing were evaluated through 3 months. Results Of 26 patients enrolled, 21 underwent the EV ICD implant procedure. There were no intraprocedural complications. After successful implantation and testing, 17 of 21 patients entered chronic follow-up. 14 patients continue follow up, representing 523 patient-months. Eight elective chronic defibrillation tests converted 7 of 7 patients with ≤ 40 J (maximum energy). Five episodes of spontaneous ventricular tachycardia (VT) were detected in 1 patient and either self-terminated or successfully defibrillated with appropriate shock. Over the total course of follow-up, 3 patients received an inappropriate shock due to; lead tip displacement with subsequent P-wave oversensing; Electromagnetic interference (EMI) in a ungrounded hot-tub; and EMI while doing plumbing work on unearthed electrical pipes, resulting in an annualized inappropriate shock rate of 6.9%. Pacing capture thresholds remained stable across time (5.1 ± 2.0 V at implant and 5.5 ± 2.7 V at 3 years); similarly, R-wave amplitudes were stable across time (3.4 ±2.0 mV at implant and 4.2 ± 2.7 mV at 3 years). Pacing thresholds tended to be lowest with the patient lying on the right side and pacing threshold often increased relative to supine position for left-side, prone or bending postures. R-wave amplitude tended to be greater when bending forward. There were 10 system or procedure-related adverse events in 8 patients through 3 years, including 3 elective system removals for: a single inappropriate shock (1), chronic defibrillation testing showing no safety margin in a patient with arrhythmogenic right ventricular dysplasia (1), intolerance to ATP (1 - high pacing threshold and frequent VT). Other than the lead tip displacement within the first 3 months, no additional clinically significant lead displacements have been observed through 3 years. Conclusion The EV ICD is a novel platform for delivering high-voltage therapy. There were no procedure and system related complications observed after the first year post-implant. Lead position and chronic system performance have generally remained stable through 3 years with a low rate of adverse events.

Development and Validation of a Prediction Model for Cardiovascular Events in Exercise Assessment of Coronary Heart Disease Patients After Percutaneous Coronary Intervention.

ObjectiveThis study aimed to develop a model for predicting cardiovascular events in the exercise assessment of patients with coronary heart disease after percutaneous coronary intervention (PCI) based on multidimensional clinical information.MethodsA total of 2,455 post-PCI patients who underwent cardiopulmonary exercise testing (CPET) at the Peking University Third Hospital from January 2016 to September 2019 were retrospectively included in this study; 1,449 post-PCI patients from January 2018 to September 2019 were assigned as the development cohort; and 1,006 post-PCI patients from January 2016 to December 2017 were assigned as the validation cohort. Clinical data of patients before testing and various indicators in the exercise assessment were collected. CPET-related cardiovascular events were also collected, including new-onset angina pectoris, frequent premature ventricular contractions, ventricular tachycardia, atrial tachycardia, and bundle branch block during the examination. A nomogram model for predicting CPET-related cardiovascular events was further developed and validated.ResultsIn the development cohort, the mean age of 1,449 post-PCI patients was 60.7 ± 10.1 years. CPET-related cardiovascular events occurred in 43 cases (2.9%) without fatal events. CPET-related cardiovascular events were independently associated with age, glycosylated hemoglobin, systolic velocity of mitral annulus, ΔVO2/ΔWR slope inflection, and VE/VCO2 slope > 30. The C-index of the nomogram model for predicting CPET-related cardiovascular events was 0.830, and the area under the ROC curve was 0.830 (95% CI: 0.764–0.896). For the validation cohort of 1,006 patients, the area under the ROC curve was 0.807 (95% CI: 0.737–0.877).ConclusionPost-PCI patients with older age, unsatisfactory blood glucose control, impaired left ventricular systolic function, oxygen uptake parameter trajectory inflection, and poor ventilation efficiency have a higher risk of cardiovascular events in exercise assessment. The nomogram prediction model performs well in predicting cardiovascular events in the exercise assessment of post-PCI patients and can provide an individualized plan for exercise risk prediction.

EVALUATION OF QUALITY OF LIFE INDICATORS IN NSTEMI PATIENTS DEPENDING ON PLASMA LEVEL ST2, NATURE OF CORONARY ARTERIES LESION AND OTHER CLINICAL CHARACTERISTICS

Introduction. The prevalence of myocardial infarction and its leading role in the structure of overall and cardiovascular mortality encourages the search for predictors of adverse disease and the search for optimal means to prevent adverse events and improve the quality of life of this category of patients. The aim of the study – to evaluate quality of life in NSTEMI patients based on plasma ST2 levels, the nature of coronary artery disease, and other clinical characteristics. Research Methods. The study involved 200 patients with NSTEMI aged 38 to 80 years. All patients were examined according to the current treatment protocol for patients with acute myocardial infarction without ST segment elevation, plasma ST2 levels were determined and quality of life was assessed using the MIDAS-35 questionnaire. Results and Discussion. Spearman's rank correlation showed that the level of physical activity (the first subscale of MIDAS-35) of patients with NSTEMI is directly correlated with the presence of frequent ventricular extra­systoles and paroxysms of ventricular tachycardia recorded during ECG monitoring on day 1 of NSTEMI, the seve­rity of coronary artery lesions and plasma ST2 levels determined on the 1st day of hospitalization. Similar patterns are found in subscales 2, 4, 5. Subscale 6 revealed the presence of a correlation only with the presence of frequent ventricular tachycardia. Subscales 3 and 7 did not show correlations with the studied parameters. Conclusions. Elevated ST2 levels, hemodynamically significant coronary artery lesions and the presence of acute arrhythmias in the early period of NSTEMI have been found to significantly affect quality of life as determined by the MIDAS-35 questionnaire. The impact on remodeling processes and the strategy of early invasive treatment in patients with NSTEMI will not only reduce the likelihood of complications, but also improve the quality of life of this category of patients.

Acute coronary syndrome with non-obstructive coronary arteries (ACS-NOCA) in patients with hypertrophic cardiomyopathy

ObjectivesOur study aimed to determine the prevalence and prognosis of acute coronary syndrome with non-obstructive coronary artery (ACS-NOCA) in patients with hypertrophic cardiomyopathy (HCM).Methods and resultsWe enrolled a total of 200 consecutive patients with HCM over a 139-month period from 2002 to 2013. The study found that 28 patients (14% of overall patients, 51% of patients with ACS) had ACS-NOCA, and 18 patients (9% of overall patients, 86% of patients with acute MI) had MINOCA as initial clinical presentations. The highest prevalence of non-obstructive coronary artery disease (NOCA) in patients with HCM was found in acute ST-elevation myocardial infarction (STEMI) (100%), followed by non-STEMI (82%), and unstable angina (29%). Patients with ACS-NOCA had more frequent ventricular tachycardia and lower resting left ventricular (LV) outflow tract gradients than those with no ACS-NOCA (p < 0.05 for all). The ACS-NOCA group had a lower probability of HCM-related death compared with the no ACS-NOCA group and the significant coronary artery disease (CAD) group (p-log-rank = 0.0018).ConclusionsMINOCA or ACS-NOCA is not an uncommon initial presentation (prevalence rate 9–14%) in patients with HCM. NOCA was highly prevalent (51–86%) in patients with HCM presenting with ACS and had a favorable prognosis. Our findings highlight as a reminder that in an era of rapid reperfusion therapy, ACS in patients with HCM is not only a result of obstructive epicardial CAD, but also stems from the complex cellular mechanisms of myocardial necrosis.

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.

Acute coronary syndrome with non-obstructive coronary arteries (ACS-NOCA in patients with hypertrophic cardiomyopathy

Abstract Background Previous case reports have described myocardial ischemia and/or infarction in hypertrophic cardiomyopathy (HCM); however, prevalence and prognosis are little known. Thus, our study aimed to determine the prevalence and prognosis of acute coronary syndrome with non-obstructive coronary artery (ACS-NOCA) in patients with hypertrophic cardiomyopathy (HCM). Methods We prospectively enrolled 200 consecutive HCM patients (mean age 66±16 years, 42% males) from 2002 to 2013 attending a tertiary referral center, King Chulalongkorn Memorial Hospital, Thailand. The median follow-up time was 13 years. ACS-NOCA was diagnosed by a clinical syndrome of acute myocardial ischemia or MI with &amp;lt;50% angiographically luminal stenosis in the major epicardial coronary branch by coronary angiogram. Results Of 200 HCM patients, 28 patients (14% of overall patients, 51% of patients with ACS) had ACS-NOCA, and 18 patients (9% of overall patients, 86% of patients with acute MI) had myocardial infarction with nonobstructive coronary artery (MINOCA) as initial clinical presentations. Of the 28 patients, 4 (14%) were STEMI, 14 (50%) were NSTEMI and 10 (36%) were UA. ACS-NOCA group had more frequent ventricular tachycardia and lower resting left ventricular (LV) outflow tract gradients than no ACS-NOCA group (p&amp;lt;0.05). The ACS-NOCA group tended to have a lower rate of HCM-related death compared with the no ACS-NOCA group and the significant coronary artery disease (CAD) group (p-log-rank = 0.0018). As shown in Figure 1. Conclusions ACS-NOCA is not an uncommon initial presentation (prevalence rate 9–14%) in patients with HCM. More than half of HCM patients presenting with ACS were found to have NOCA. ACS-NOCA was not associated with an increased mortality, but had a more favorable prognosis. Funding Acknowledgement Type of funding sources: None. Figure 1

Mutation in a non-desmosomal gene is associated with poor outcome of endo-epicardial ventricular tachycardia ablation in patients with nonischaemic cardiomyopathy

Abstract Background Nonischaemic cardiomyopathy (NICM) represents a heterogenic disorder with a variable arrhythmogenic substrate. Its location is often epicardial and catheter ablation in this location proved to be an effective therapeutic modality in NICM patients with recurrent ventricular tachycardias (VTs). Purpose To determine the impact of the type of genetic mutation on the long-term outcome of endo-epicardial ablation in patients with NICM. Methods We investigated 82 patients (age 47±15 years, 10 women) with NICM who underwent endo-epicardial ablation for frequent VTs. Of them, 59% had a history of failed endocardial ablation. Patients had a left ventricular ejection fraction of 44±14% and all were implanted with cardioverter-defibrillator. One hundred candidate genes were examined using the new generation sequencing technique. Results Mutation in genes coding desmosomal complex (genes: PKP2, DSC, DSP, and DSG) was found in 30% of patients (“desmosomal” group). In 23% of patients, other gene mutations (genes: LMNA/C, MYH7, DES, TTN, RYR2, TPM1, MYPN, FLNC, and SCN5A) were detected (“non-desmosomal” group). In 46% of subjects no pathogenic mutation could be identified (“none” group). During a mean follow up of 34±33 months, patients in the “non-desmosomal” group were at significantly higher risk of VT recurrence and death/heart transplant compared to patients in the “desmosomal” group (Figure 1). Conclusion Potentially pathogenic mutation can be detected in about half of patients with NICM undergoing endo-epicardial VT ablation. Most commonly, mutations can be found in genes coding desmosomal complex and the endo-epicardial ablation is then associated with a satisfactory low VT recurrence rate and excellent survival in the long-term. On the other hand, patients with a mutation in non-desmosomal genes have poor outcomes despite endo-epicardial ablation. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Supported by Ministry of Health of the Czech Republic, grant nr. NV18-02-00237 Figure 1

The prevalence of cardiac sarcoidosis is underestimated: [18F]FDG-PET is the answer

Abstract Funding Acknowledgements Type of funding sources: None. Background Overt cardiac involvement is reported in 5% of patients with sarcoidosis, although autopsy and imaging studies suggest higher prevalence, worldwide variation. The role of 18F-fluorodeoxyglucose positron emission tomography ([18F]FDG-PET) in non-invasive diagnosis and follow-up has increased in the last decade. Purpose Our goal is to describe the prevalence, clinical manifestations and outcomes of cardiac sarcoidosis (CS), diagnosed through [18F]FDG-PET, in a southern European population. Methods We included all patients with histological diagnosis of extracardiac sarcoidosis screened with [18F]FDG-PET between 2009 and 2020. We collected data on clinical manifestations, cardiac magnetic resonance (CMR) results, and mortality outcomes and compared those with and without cardiac involvement. We applied the criteria for the diagnosis of CS from Heart Rhythm Society. Results Of the 400 patients screened with [18F]FDG-PET, 128 had a histological diagnosis of extracardiac sarcoidosis (54.7% females, mean age 51.0 ± 14.2 years). None underwent endomyocardial biopsy. Ten patients had a pattern of [18F]FDG uptake consistent with CS defined as diffuse (n = 5), focal (n = 3), and focal on diffuse (n = 2). Of the 128 patients, 14 also underwent CMR, which identified 2 subjects with positive findings in both modalities and 3 additional patients: focal (n = 1), multifocal mid-wall (n = 2), focal mid-wall (n = 2), and multifocal subepicardial (n = 1) delayed gadolinium enhancement. Overall, 13 patients (10.2%) fulfilled the criteria for probable CS (53.8% female, mean age 56.2 ± 12.6 years), all with multiorgan involvement, mostly lung and lymph nodes (each 92%), followed by skin and central nervous system (each 15%). Median left ventricle ejection fraction was 62% [55-65] and there were cardiac manifestations of CS in 6 patients (46%): sick sinus syndrome (n = 2), complete heart block (n = 1), frequent premature ventricular complexes (n = 1), ventricular tachycardia plus heart failure (n = 1), and bifascicular block plus heart failure (n = 1). Eleven patients (85%) with probable CS were medicated with immunosuppressant drugs: corticosteroids (n = 9), methotrexate (n = 4), and azathioprine (n = 2). Four patients with previous [18F]FDG screening were revaluated after treatment, each showing no cardiac uptake. After a mean follow-up of 4.0 ± 1.0 years, mortality was three-fold higher in patients with cardiac involvement, despite the absence of statistical significance (15% vs. 5%, P = 0.151). Conclusions In a southern European population with histological extracardiac sarcoidosis, the prevalence of cardiac involvement was 10.2%, most asymptomatic. [18F]FDG-PET improves the diagnostic yield and plays an important role in monitoring response to therapy. The higher mortality trend in those with CS needs to be ascertained in longer follow-up.

The consequence of biomarkers of myocardial fibrosis in the prediction of arrhythmias in patients with hypertension in combination with coronary heart disease (literature review)

The main morphological structural lesion substrate is myocardial fibrosis. The processes of fibrosis in a certain way are associated with the severity of a variety of cardiac arrhythmias. Myocardial fibrosis may be manifested by prolongation of the QRS complex, frequent ventricular arrhythmias and ventricular tachycardia on the electrocardiogram. Echocardiography is the main tool used to assess the structure and function of the heart, it reveals an increase in the left ventricle, and decrease in ejection fraction and diastolic dysfunction of the left ventricle and an increase in filling pressure. Biological markers are quantitatively defined biological parameters that, as indicators, determine the norm, pathology and result of medecinal correction of the disease (definition of experts from the Biomarkers Definitions Working Group, USA). Changes of biomarkers can be controlled to determine the individual risk of cardiovascular diseases development and measures to normalize them. Among the main causes of fibrosis activation, hyperactivation of the renin-angiotensin-aldosterone system and, as a consequence, the excessive formation of angiotensinogen and aldosterone are considered; increased levels of galectin-3, which contributes to the migration of macrophages, proliferation of fibroblasts and collagen synthesis in cardiomyocytes. Recently, much attention is paid to the study of biochemical markers such as aldosterone, galectin-3 and transforming growth factor- beta-1.Thus, these markers were determined in hypertension, metabolic syndrome, congestive heart failure, hypertrophic cardiomyopathy, myocardial infarction, atrial fibrillation. However, to date studies considering association between frequent ventricular premature beats, as a marker of electrical instability and plasma levels of biomarkers of fibrosis, such as aldosterone, galectin-3and transforming growth factor beta-1, in patients with essential hypertension without / or in combination with coronary heart disease are absent. Based on the aforesaid material,, further thorough study of this problem is promising.

Successful management of several types of fascicular ventricular tachycardias in an 1-year old girl using a combined pharmacological and invasive approach

Idiopathic fascicular ventricular tachycardia (VT), which in most cases is sensitive to verapamil, is eliminated with high efficiency using radiofrequency ablation (RFA). In this case, we would like to demonstrate our experience of the effective use of catheter RFA in a 12-month-old child who suffered from frequent recurrent VT paroxysms accompanied by syncope.