ResearchPad - complex-case-study https://www.researchpad.co Default RSS Feed en-us © 2020 Newgen KnowledgeWorks <![CDATA[Use of the Leadless Pacemaker to Provide Empiric Pacing Support for a Young Patient with Prior Ablation of a Mid-septal Accessory Pathway Resulting in Damage to the Compact AV Node]]> https://www.researchpad.co/article/elastic_article_16288 The leadless cardiac pacemaker was selected to provide empiric pacing support in this patient with a manifest mid-septal accessory pathway who had undergone a previous ablation resulting in injury to the compact atrioventricular node. Although this patient’s accessory pathway currently demonstrates stable antegrade conduction properties, diminished and complete resolution of manifest pre-excitation has been well described in patients with Wolff–Parkinson–White syndrome. Because of the patient’s young age, an increased risk is present for long-term complications inherent with traditional transvenous pacing. The Nanostim leadless pacemaker (St. Jude Medical, St. Paul, MN, USA) was implanted into the right ventricular myocardium without complication. Pacing performance has remained stable, and the patient has been free of device-related adverse events at 19 months after implant.

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<![CDATA[Subcutaneous Implantable Cardioverter-Defibrillator Shock: Appropriate or Inappropriate?]]> https://www.researchpad.co/article/elastic_article_16286 In this report, an unusual case of different defibrillator shocks in a single patient is described, and the interpretation and appropriate classification of subcutaneous implantable cardioverter-defibrillator therapy is discussed.

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<![CDATA[Paced or Non-Paced? Examining an Electrocardiogram Rythm]]> https://www.researchpad.co/article/elastic_article_16283 Many patients who present for pacemaker follow-up one week after device implantation have a “different” presenting rhythm, which can be puzzling to examine for even the most experienced cardiac device clinicians. Novel implanting techniques on the horizon necessitate a thorough understanding of these new technologies to provide safe care in this patient population.

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<![CDATA[An Atypical Presentation of Right Atrial Flutter Following the Cox Maze Procedure and Left Atrial Reduction Surgery: A Case Report]]> https://www.researchpad.co/article/elastic_article_16272 The onset of recurrent atrial tachyarrhythmia (ATA) following the Cox maze procedure (CMP) is commonly encountered, and may be associated with increased perioperative mortality. The majority of recurrent ATA cases are localized to the left atrium following surgical ablation. Right atrial flutter (AFL) following the CMP is a less-frequent occurrence, and may pose a diagnostic challenge due to uncharacteristic surface electrocardiogram (ECG) and intracardiac activation patterns. In this case, a 68-year-old male who had previously undergone left-sided surgical ablation with left atrial reduction for the treatment of persistent atrial fibrillation during coronary artery bypass and mitral valve repair developed symptomatic atypical AFL. The patient was intolerant to amiodarone, and was thus scheduled for ablation. Given the patient’s history of extensive left atrial instrumentation and surface ECG findings indicating an atypical AFL, the decision was made to proceed with left atrial mapping. During the electrophysiology study, initial activation mapping was not suggestive of a cavotricuspid isthmus reentrant arrhythmia. Here, we describe the possible mapping pitfalls associated with a persistent tachyarrhythmia that was ultimately proven to be a right AFL, despite atypical activation patterns.

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<![CDATA[The Importance of Right Ventricular Lead Positioning in Determining Outcomes of Cardiac Resynchronization Therapy]]> https://www.researchpad.co/article/elastic_article_16264 Cardiac resynchronization therapy is known to improve clinical outcomes in patients with heart failure and left ventricular dyssynchrony. However, the optimal positioning of the right ventricular lead is unknown, and there is conflicting data on the acute hemodynamic effects and long-term outcomes. Here, we present a case of a patient who underwent implantation of a dual-chamber pacemaker for complete heart block, but who after three months, still had symptoms consistent with New York Heart Association (NYHA) Class IV heart failure. After optimal medical therapy failed and a left ventricular lead was placed, he still remained symptomatic, so the right ventricular lead was repositioned from the right ventricular outflow tract to the right ventricular apex. Afterwards, the patient’s symptoms improved from NYHA Class IV to NYHA Class II, and his left ventricular ejection fraction improved from 20% to 45%.

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<![CDATA[Significant Lead Migration of a Subcutaneous Implantable Cardioverter-Defibrillator in a Pediatric Patient]]> https://www.researchpad.co/article/elastic_article_16251 Since its introduction, the subcutaneous implantable cardioverter-defibrillator (S-ICD) has provided the benefit of reduced mortality from ventricular tachyarrythmias without the associated short- and long-term morbidity of transvenous or epicardial implantable cardioverter-defibrillator (ICD) leads. As its name implies, the S-ICD system is implanted in its entirety, including device and lead, just under the skin beginning along the anterior axillary line, with its lead tunneled to the left parasternum and then from the xiphoid to the manubrium–sternal junction. Dislocation of the lead due to migration of the parasternal lead has been described in a minority of patients. Here, we describe an unusual case of a significant lead migration in a pediatric patient.

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<![CDATA[Left Subclavian and Innominate Vein Balloon Venoplasty Followed by Permanent Pacemaker Implantation: A Case Report]]> https://www.researchpad.co/article/elastic_article_16231 Upper-extremity venous obstruction is not an uncommon problem encountered by electrophysiologists. The placement of any catheter including pacemaker leads can cause stenosis or total obstruction. Affected patients often require balloon venoplasty to facilitate lead implantation. If the vein is unresponsive to venoplasty, stenting of the vein should be contemplated. We report a case of permanent pacemaker implantation after balloon venoplasty of the left subclavian vein and innominate vein following total occlusion in a patient with symptomatic complete heart block. There are many case reports to date in which balloon venoplasty of the subclavian vein has been performed before upgrading a single-chamber pacemaker to a DDD-mode pacemaker, cardiac resynchronization therapy device, or implantable cardioverter-defibrillator because of chronic venous occlusion secondary to a preexisting pacing lead. Balloon venoplasty to increase the diameter of a target vein or to overcome stenosis may be a technique that implanting electrophysiologists could adopt in order to achieve success in patients with more challenging anatomies.

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<![CDATA[Ineffective Shock Deliveries in a Patient with Ischemic Cardiomyopathy: Shock Vector Matters]]> https://www.researchpad.co/article/elastic_article_16222 A 56-year-old male who had previously received an implantable cardioverter-defibrillator for primary prevention was admitted to the hospital with frequent shocks. Device interrogation revealed ineffective shock deliveries. Possible explanations for failed treatment are discussed herein.

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<![CDATA[Chest Pain Resolution with His-bundle Pacing in a Patient with Left Bundle Branch Block–related Nonischemic Left Ventricular Dysfunction]]> https://www.researchpad.co/article/elastic_article_16221 Chest pain in patients with left bundle branch block (LBBB) and normal coronaries has been reported previously in the literature. Prior cases of intermittent LBBB and “chest pain syndrome” are known of, but the causes of and treatment options for such remain unclear. A mechanism of myocardial dyssynchrony has been proposed as a possible cause of the pain, but this has not yet widely been investigated. The application of His-bundle pacing techniques to promote normal activation of the conduction system may be a treatment option. The function of cardiac implantable electronic devices can be followed via remote monitoring (RM), a vital tool in this unique patient population. The present report introduces the case of a 51-year-old female to highlight this under-recognized syndrome, including the pacing technologies used for treatment and the crucial role of RM follow-up in such affected individuals.

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<![CDATA[Successful Ablation of Epicardial Premature Ventricular Complexes Near the Great Cardiac Vein from the Left Ventricular Endocardium Despite Predictors of Failure]]> https://www.researchpad.co/article/elastic_article_16215 Mapping and ablating premature ventricular complexes (PVCs) that originate near the great cardiac vein (GCV) and anterior interventricular vein (AIV) can pose several challenges related to the advancement and positioning of catheters within these veins, the delivery of effective lesions, and the risk of collateral injury to the left coronary arteries and left phrenic nerve. When ablation of these PVCs from inside the GCV/AIV is not possible, a systematic assessment of nearby vantage points, such as the left coronary cusp (LCC) and left ventricular (LV) endocardial breakout site, should be considered, in addition to the performance of a more invasive epicardial ablation procedure via a percutaneous pericardial puncture or thoracotomy. Several electrocardiographic, anatomic, and electrogram timing features have been shown to predict the likelihood of successful ablation from a non-epicardial site, such as the LCC or LV endocardium, but none of these spots is considered to be a perfect location. The case described here in this report is a demonstration of a safe and successful ablation of GCV PVCs from the LV endocardial breakout site using adequate power and lesion duration, even when the site was 17 mm away from the putative origin, and some previously described electrocardiographic and electrogram-based predictors of success suggested the outcome would not be positive.

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<![CDATA[Intraoperative Epicardial Triventricular Pacing in a Pediatric Patient]]> https://www.researchpad.co/article/elastic_article_16206 Cardiac resynchronization therapy (CRT) is used as an adjunctive therapy in adults with advanced heart failure but remains less commonly applied in pediatric patients. Further, CRT is traditionally conducted via biventricular transvenous pacing from the right ventricle and coronary sinus to activate the left ventricle and improve electromechanical synchrony; however, triventricular pacing, in which a third ventricular lead is utilized to activate an additional ventricular location, has been shown to be a feasible therapeutic alternative to typical CRT in patients with advanced heart failure or nonresponders. Limited adult studies involving triventricular pacing have been performed to date but no pediatric data are available. Thus, we present the case of a 12-month-old patient with congenital complete heart block and subsequent pacemaker-induced cardiomyopathy in whom triventricular epicardial pacing was applied in an effort to increase the available knowledge.

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<![CDATA[Catheter Ablation of Ischemic Ventricular Tachycardia Originating from an Inferobasal Right Ventricular Scar Using Substrate Mapping: A Case Report]]> https://www.researchpad.co/article/elastic_article_16200 Catheter ablation of ventricular tachycardia (VT) has emerged as a superior alternative to antiarrhythmic drug therapy in patients with ischemic cardiomyopathy, with the vast majority of ischemic VT being ablation from the endocardial surface of the left ventricle (LV). While rare, the possibility of ischemic right ventricular (RV) VT should also be entertained, especially in patients with previous myocardial infarction and in those individuals in whom LV endocardial ablation fails to abolish VT. Further, success rates remain disappointing in some of these cases, often owing to difficulties in mapping the tachycardia due to hemodynamic instability during VT. We report a case of hemodynamically unstable ischemic VT successfully ablated from the endocardial surface of the LV and RV using a substrate mapping approach in a patient with a large inferior myocardial infarction, involving RV infarction.

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<![CDATA[The Rogue P-wave: Atrial Dissociation Following Bicaval Heart Transplantation]]> https://www.researchpad.co/article/elastic_article_16198 We report the first case, to our knowledge, of atrial dissociation in a patient who underwent bicaval orthotopic heart transplantation. It was believed that atrioventricular dissociation prompting pacemaker implantation likely represented donor sinus bradycardia/arrest with intact atrioventricular conduction with surgically isolated recipient atrial activity.

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<![CDATA[Utility of a Leadless Pacemaker as a Backup to Left Ventricle–only Pacing in a Patient with Prior Device-related Severe Tricuspid Regurgitation]]> https://www.researchpad.co/article/elastic_article_13313 The contribution of endocardial cardiac device leads to severe tricuspid regurgitation (TR) has become increasingly recognized. Current strategies for treating cardiac device lead–related TR have limitations. We present a case of a pacemaker-dependent patient with severe TR as a complication of multiple cardiac device leads who underwent laser lead extraction, which was followed by implantation of a dual-chamber pacemaker with a coronary sinus lead for left ventricular pacing and a leadless transcatheter pacemaker for backup right ventricular (RV) pacing. This report represents one of the first cases of a leadless pacemaker implanted for RV backup pacing, highlighting the possibility of future biventricular pacing therapy (with a leadless pacemaker in VVT mode) without endocardial leads crossing the tricuspid valve.

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<![CDATA[Patent Foramen Ovale as a Rare Focus of Origination of Atrial Tachycardia]]> https://www.researchpad.co/article/elastic_article_13305 Supraventricular tachycardia refers to a group of arrhythmias whose mechanism involves tissues from the His bundle or above. Repetitive focal atrial tachycardia (AT) (FAT) accounts for less than 10% of supraventricular tachycardia cases. FAT originating from the patent foramen ovale (PFO) has not been well-described and is a rarely reported phenomenon to date. Here, we report a rare case of FAT arising from the PFO. To the best of our knowledge, this is the first detailed report of AT arising from the PFO. We have included the description of the ablation procedure and postulated the possible electrophysiological mechanisms of a regularly irregular FAT noted in our patient during the electrophysiology study. Our case shows catheter ablation to be a successful treatment strategy in AT arising from the PFO, with the possibility of providing a long-term cure and freedom from antiarrhythmic drugs.

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<![CDATA[An “UninTENSional” Subcutaneous Implantable Cardioverter-defibrillator Shock]]> https://www.researchpad.co/article/elastic_article_13304 Subcutaneous implantable cardioverter-defibrillators (ICDs) (S-ICDs) are advantageous because they eliminate the need for transvenous leads. However, just like in the case of traditional ICDs, inappropriate shocks are an unwanted complication that may result following their placement. In this case, we discuss the mechanism of an inappropriate shock in a patient with an S-ICD.

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<![CDATA[Acute Water Ingestion as a Treatment for Postural Orthostatic Tachycardia Syndrome]]> https://www.researchpad.co/article/elastic_article_13302 A 24-year-old female presented to our clinic with symptomatic tachycardia. In the clinic, she was able to replicate her symptoms, which were due to tachycardia in a standing position that resolved upon sitting. The patient was then offered eight ounces (236.6 mL) of water and, after consumption of such, the standing tachycardia was no longer observed. A diagnosis of postural orthostatic tachycardia syndrome (POTS) was made. This case report discusses a novel approach to acute treatment for POTS.

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<![CDATA[Surgical Mapping and Ablation in the Left Ventricular Summit Guided by Presurgery Pericardial Mapping]]> https://www.researchpad.co/article/elastic_article_13301 Successful catheter ablation of ventricular arrhythmias arising from the left ventricular (LV) summit is challenging. The use of a catheter-based epicardial approach may be limited due to the proximity of the major coronary arteries and the presence of epicardial fat. Surgical cryoablation in the LV summit is a viable option for drug-refractory ventricular arrhythmias. Presurgical epicardial mapping can facilitate the surgical procedure by localizing the area of interest to allow for a more limited surgical dissection of the epicardial fat.

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<![CDATA[Selective His-bundle Pacing May Preserve Intrinsic Repolarization as Well as Depolarization]]> https://www.researchpad.co/article/elastic_article_13298 A 79-year-old man with chronic atrial fibrillation underwent single-chamber His-bundle pacemaker implantation. The post-implant electrocardiogram (ECG) demonstrated selective His-bundle capture, with a narrow paced QRS and repolarization pattern similar to that of the baseline ECG. Furthermore, repolarization changes prototypic of ventricular pacing did not occur with selective His-bundle capture. While His-bundle pacing, with or without selective His-bundle capture, can preserve physiologic patterns of depolarization, only His-bundle selective pacing can preserve intrinsic ST- and T-wave patterns. Thus, the maintenance of physiologic repolarization may have various advantages, including accurate interpretation of ECG changes that are not generally interpretable in the setting of ventricular pacing.

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<![CDATA[The Mysterious Case of an Athletic Woman with Recurrent Syncope and a “Normal” Heart]]> https://www.researchpad.co/article/elastic_article_13293 A 53-year-old female with a history of sports participation presented to a community hospital emergency department for collapse. She was given a LifeVest® wearable cardioverter-defibrillator (WCD) (Zoll Medical Corp., Chelmsford, MA, USA) and scheduled to undergo cardiac magnetic resonance imaging (MRI) with gadolinium enhancement at a tertiary center. However, before the scheduled MRI scan could be performed, she developed tachycardia, for which the WCD alarmed. A dual-chamber implantable cardioverter-defibrillator was subsequently implanted. Assessment of a patient with syncope requires consideration of the idea that a life-threatening and recurrent arrhythmia may be a cause for the problem. However, current guidelines do not cover the routine use of WCDs in syncope. Additionally, the patient described here did not clearly meet United States Food and Drug Administration indications for the provision of an external defibrillator. We present this case to provoke discussion among colleagues regarding this patient’s treatment plan.

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