Background: AF in the setting of cardiac amyloidosis is associated with a high risk of TEs, irrespective of CHA2DS2-VASc score. While warfarin has been the traditional anticoagulant, DOACs offer a promising alternative, but their safety in this population remains underexplored. This study aimed to evaluate the prevalence of thromboembolic events (TEs), including stroke and transient ischemic attack (TIA), and major bleeding events in patients with cardiac amyloidosis (CA) and atrial fibrillation (AF) treated with either warfarin or direct oral anticoagulants (DOACs). Additionally, we aimed to explore whether DOACs are at least as effective as warfarin in protecting against TEs in this population. Methods: This retrospective cohort study analyzed 422 patients with confirmed CA and AF from Mayo Clinic, with a median follow-up of 4.3 years. Data on anticoagulation therapy, baseline characteristics, and outcomes (TEs and bleeding) were collected. Statistical analyses included chi-square tests, t-tests, and Cox regression to assess the relationship between anticoagulation and TE. Results: Among 422 patients, 21 experienced a TE. The annual event rate was 0.83% for warfarin and 0.67% for DOACs, with no significant difference (HR 0.66, CI 0.22–2.01, p = 0.5). Patients with anticoagulation interruptions > 5 days had increased TE risk (HR 3.19, CI 0.97–10.5, p = 0.056). The bleeding rate was 9.9% over 4.3 years (2.33% per year), with no significant differences between anticoagulants. Conclusions: Both warfarin and DOACs have similar, low risks of TEs in CA and AF patients. However, anticoagulation interruptions were associated with increased TE risk, emphasizing the challenges in managing anticoagulation in this population.
Late Sustained Ventricular Arrhythmias After Left Ventricular Assist Device Implantation: Outcomes and Predictors
ABSTRACTBackgroundThe factors contributing to sustained ventricular arrhythmias (VAs) >30 days after left ventricular assist device (LVAD) implantation are not well‐established.ObjectivesThis study aimed to predict the factors associated with late sustained VAs after LVAD implantation and develop a predictive score to identify patients with an increased risk of late sustained VAs after the procedure.MethodsWe performed a retrospective cohort study on a training cohort of 623 patients and a validation cohort of 157 patients who underwent LVAD implantation at the Mayo Clinic (Rochester, Phoenix, and Jacksonville) from January 1, 2000, to December 30, 2020. Late sustained VAs were defined as ventricular tachycardia (VT) and ventricular fibrillation (VF) occurring >30 days after the LVAD procedure. Detailed chart reviews of the electronic health records within the Mayo Clinic and outside medical records were performed.ResultsA total of 780 patients were included in our study. Late sustained VAs occurred in 30% (n = 232) of the patients. The significant factors associated with late sustained VAs after LVAD were the history of VAs prior to LVAD (34.1% vs. 23.0%, p < 0.01), implantable cardiac defibrillator (ICD) (87.9% vs. 77.6%, p < 0.01) or cardiac resynchronization therapy (CRT) in situ (43.5% vs. 33.6%, p = 0.008), VT ablation prior to LVAD (5.2% vs. 1.8%, p = 0.010), use of amiodarone (49.1% vs. 38.7%, p = 0.007), use of mexiletine (15.5% vs. 5.7%, p < 0.01), and higher left ventricular end‐diastolic diameter (LVEDD) on echocardiography prior to LVAD implantation (71.4 vs. 68.7 mm, p = 0.002). During follow‐up, the patients who developed late sustained VAs after LVAD had lower survival than those who did not (HR = 1.96, 95% CI:156–2.4, p < 0.001). The average time from LVAD to orthotopic heart transplant was longer among late sustained VAs patients (23 vs. 14 months, p < 0.01). The “VIN” risk score was created to identify four risk groups: low (scores 0), intermediate (score 1), high (score 2), and very high (score 3). The rates of late VA's in the training cohort at 1 year were 9.5%, 14%, 18%, and 25% which was almost similar to the risk of late VA's at validation cohort 10%, 12%, 20%, and 63%, respectively.ConclusionsLate sustained VAs occurred in 30% of the patients who received LVAD and were associated with lower survival. The VIN risk score was developed and validated to stratify patients into low, intermediate, high, and very high risk of late sustained VAs.
Arrhythmias in Cardiac Sarcoidosis: Management and Prognostic Implications
Cardiac sarcoidosis (CS) is characterized by various arrhythmic manifestations ranging from catastrophic sudden cardiac death secondary to ventricular arrhythmia, severe conduction disease, sinus node dysfunction, and atrial fibrillation. The management of CS is complex and includes not only addressing the arrhythmia but also controlling the myocardial inflammation resultant from the autoimmune reaction. Arrhythmic manifestations of CS carry significant prognostic implications and invariably affect long-term survival in these patients. In this review, we focus on management of arrhythmic manifestation of cardiac sarcoidosis as well as risk stratification for sudden cardiac death in these patients.
Electrical storm after left ventricular assist device (LVAD) implantation
AbstractIntroductionVentricular tachycardia storm or electrical storm (ES) is a common complication following left ventricular assist device (LVAD) implantation. The factors contributing to ES and outcomes are less studied. The study aimed to determine the factors associated with ES and the probability of survival in patients undergoing LVAD in three tertiary centers over a span of 15 years.MethodsWe performed a retrospective cohort study on all patients who underwent LVAD implantation at the Mayo Clinic (Rochester, Phoenix, and Jacksonville) from January 1, 2006 to December 31, 2020. ES was defined as ≥3 episodes of sustained ventricular tachycardia over a period of 24 h with no identifiable reversible cause. Detailed chart reviews of the electronic health records within the Mayo Clinic and outside medical records were performed.ResultsA total of 883 patients who underwent LVAD implantation were included in our study. ES occurred in 7% (n = 61) of patients with a median of 13 days (interquartile range [IQR]: 5–297 days) following surgery. We found 57% of patients (n = 35) developed ES within 30 days, while 43% (n = 26) patients developed ES at a median of 545 (IQR 152–1032) days after surgery. Following ES, 26% of patients died within 1 year. Patients with ES had a significant association with a history of ventricular arrhythmias and implantable cardioverter defibrillator (ICD) shocks before the procedure. ES was significantly associated with reduced survival compared to patients without ES (hazards ratio [HR]: 1.92, 95% CI: 1.39–2.64, p < .001).ConclusionFollowing LVAD implantation, the rate of ES was 7% with majority of ES occurring within 30 days of LVAD. Risk factors for ES included pre‐implant history of ventricular arrhythmias and ICD shock. ES was significantly associated with reduced survival compared to patients without ES.
Metastatic ER+ Breast Cancer: Mechanisms of Resistance and Future Therapeutic Approaches
Endocrine therapy is the main treatment for hormone receptor-positive (HR+) breast cancer. However, advanced tumors develop resistance to endocrine therapy, rendering it ineffective as the disease progresses. There are several molecular mechanisms of primary and secondary endocrine resistance. Resistance can develop due to either alteration of the estrogen receptor pathway (e.g., ESR1 mutations) or upstream growth factors signaling pathways (e.g., PI3K/Akt/mTOR pathway). Despite progress in the development of molecularly targeted anticancer therapies, the emergence of resistance remains a major limitation and an area of unmet need. In this article, we review the mechanisms of acquired endocrine resistance in HR+ advanced breast cancer and discuss current and future investigational therapeutic approaches.
Immune checkpoint inhibitor myocarditis with complete heart block: a case series
Abstract Funding Acknowledgements Type of funding sources: None. Background/Introduction Immune checkpoint inhibitor (ICI) myocarditis is a life-threatening condition characterized by lymphocytic myocardial infiltration[1]. Complete heart block (CHB) occurs in 15% of cases and is often fatal[2-4]. The nature and optimal management of this often-malignant condition is poorly understood[5]. Purpose This case series assesses prognostic factors associated with survival at 90 days among people with ICI myocarditis and CHB. Methods The electronic patient record system was used to identify patients admitted with ICI myocarditis. A two-physician review was used to assess the presence of ICI-associated CHB. Wilcoxon rank sum and Spearman’s rank correlation were used for categorical and quantitative variables respectively. Data was analysed using STATA/IC 16.1. The primary outcome was person-day survival 90 days after presenting symptom onset. Results Six patients were included in the final analysis. Mean survival was 47 person days. All had metastatic disease and presented 15 to 32 days after the first ICI infusion. All had muscle weakness. Other common self-symptoms were shortness of breath (4), blurred vision (4), double vision (3), collapse (3), and leg swelling (1). Proximal myopathy (2), fatigable myopathy (1), ptosis (3), and peripheral oedema (1) were present on examination. Raised troponin T and white blood cell count (WBC) were associated with 90-day survival (see Table 1). Nt-pro BNP, AST, and CK levels were raised in all patients. Two patients were tested for anti-striated muscle antibody titres, and both were strongly positive. Increase in QRS duration compared to baseline ECG was associated with lower survival at 90 days. Only one patient had CHB on admission. Steroid dose, IVIG, and plasmapheresis weren’t associated with survival. One patient declined device therapy. One declined permanent pacemaker (PPM) after insertion of transvenous pacemaker (TVP). Both died within 2 weeks. Three people underwent insertion of a transvenous pacemaker (TVP) followed by PPM insertion (table 2). All three eventually died within 100 days. One person received isoproterenol and immunosuppression as a bridge to PPM and survived. One patient was managed initially with TVP but subsequently declined PPM insertion. TVP removal resulted in CHB recurrence, and they died shortly after discharge. One person declined device therapy and died while receiving comfort care. Lead malfunction was frequent. One patient experienced bradycardia arrest with failure of a TVP lead to capture, while another experienced lead dislodgement. Conclusion CHB secondary to ICI is often fatal. It should be considered in patients presenting with symptoms of myositis, raised troponin and increased QRS duration. Despite a small sample size, this study identifies several prognostic factors which can guide both patients and physicians with decision-making. Larger studies are needed to better understand the role of device therapy in this population.
Causes of Early Mortality After Catheter Ablation of Atrial Fibrillation
Background: Recognition of the causes of early mortality after atrial fibrillation (AF) catheter ablation is essential for the improvement of patient safety. This study sought to determine the causes of early mortality (≤90 days) after AF ablation. Methods: We performed a retrospective analysis of AF ablation from January 1, 2013, to December 1, 2021 at the Mayo Clinic (Rochester, Phoenix, and Jacksonville). Causes of death were identified through a comprehensive chart review of the electronic health record from within the Mayo Clinic system and outside records when available. Results: A total of 6723 patients were included in the study. The 90-day all-cause mortality rate was 0.22% (n=15). Among all 90-day deaths, majority of the deaths (73.3%) did not have a direct relationship with the procedure. Sudden death was the most common cause of early death (20%), followed by peri-procedural stroke (13%), respiratory failure (13%), atrioesophageal fistula (13%), infection (7%), heart failure (7%), and traumatic brain injury (7%). The 90-day mortality rate directly due to AF ablation procedural complications was 0.06% (n=4). Conclusions: AF ablation procedure has a 90-day mortality of 0.22%, and the most common cause of early mortality was sudden death. The majority (73.3%) of early mortality was not directly associated with a procedural complication, and the mortality rate due to complications associated with the AF ablation procedure was low at 0.06%. Further studies are required to investigate causes and risk factors associated with sudden death in this patient population.