Repeated misclassifications of tachycardia by an implantable cardiac defibrillator

This case describes repeated misclassifications of SVT due to AV node reentry as VT by an ICD. This case illustrates the limitations of SVT-VT discrimination algorithm. Careful analysis of the stored tracings is of critical importance to reach the correct diagnosis

Continuous positive airway pressure ameliorated severe pulmonary hypertension associated with obstructive sleep apnea.

A 52-year-old obese woman was admitted to our institution for evaluation of dyspnea and pulmonary hypertension (PH). Polysomnography revealed severe obstructive sleep apnea (OSA) with an apnea hypopnea index of 99.8. Treatment with nocturnal continuous positive airway pressure (CPAP) resulted in correction of daytime hypoxemia, hypercapnia, and near-normalization of pulmonary artery pressure. To our knowledge, this is the most severe case of OSA-associated PH (approximately70 mmHg) reported to date, and it was successfully treated with nocturnal CPAP. This case demonstrates that OSA should be considered and polysomnography performed in all patients with PH, irrespective of severity, and that nocturnal CPAP has therapeutic effects on both OSA and daytime PH.</p

Dual Antiplatelet Therapy Can Be Discontinued at Three Months after Implantation of Zotarolimus-Eluting Stent in Patients with Coronary Artery Disease

Dual antiplatelet therapy (DAPT) after percutaneous coronary intervention increases the risk of bleeding. We studied the safety and clinical outcomes of switching from DAPT to aspirin monotherapy at 3 months after ZES implantation. We retrospectively evaluated 168 consecutive patients with coronary artery disease who had been implanted with a ZES from June 2009 through March 2010. After excluding 40 patients according to exclusion criteria such as myocardial infarction, 128 patients were divided into a 3-month DAPT group (67 patients, 88 lesions) and a 12-month conventional DAPT group (61 patients, 81 lesions). Coronary angiographic followup and clinical followup were conducted at more than 8 months and at 12 months after ZES implantation, respectively. Minor and major bleeding events, stent thrombosis (ST), and major adverse cardiac events (MACE) (death, myocardial infarction, cerebrovascular accident, target lesion revascularization, and target vessel revascularization) were evaluated. There were no statistically significant differences in the incidences of ST and MACE between the two groups. The incidence of bleeding events was significantly lower in the 3-month group than in the 12-month group (1.5% versus 11.5%, ). DAPT can be safely discontinued at 3 months after ZES implantation, which reduces bleeding risk

Significance of Exercise-Related Ventricular Arrhythmias in Patients With Brugada Syndrome

Background Sinus tachycardia during exercise attenuates ST‐segment elevation in patients with Brugada syndrome, whereas ST‐segment augmentation after an exercise test is a high‐risk sign. Some patients have premature ventricular contractions (PVCs) related to exercise, but the significance of exercise‐related PVCs in patients with Brugada syndrome is still unknown. The objective of this study was to determine the significance of exercise‐related PVCs for predicting occurrence of ventricular fibrillation (VF) in patients with Brugada syndrome. Methods and Results The subjects were 307 patients with Brugada syndrome who performed a treadmill exercise test. We evaluated the occurrence of PVCs at rest, during exercise and at the peak of exercise, and during recovery after exercise (0–5 minutes). We followed the patients for 92±68 months and evaluated the occurrence of VF. PVCs occurred in 82 patients (27%) at the time of treadmill exercise test: PVCs appeared at rest in 14 patients (4%), during exercise in 60 patients (20%), immediately after exercise (0–1.5 minutes) in 28 patients (9%), early after exercise (1.5–3 minutes) in 18 patients (6%), and late after exercise (3–5 minutes) in 12 patients (4%). Thirty patients experienced VF during follow‐up. Multivariable analysis including symptoms, spontaneous type 1 ECG, and PVCs in the early recovery phase showed that these factors were independently associated with VF events during follow‐up. Conclusions PVCs early after an exercise test are associated with future occurrence of VF events. Rebound of vagal nerve activity at the early recovery phase would promote ST‐segment augmentation and PVCs in high‐risk patients with Brugada syndrome

Omecamtiv mecarbil in chronic heart failure with reduced ejection fraction, GALACTIC‐HF: baseline characteristics and comparison with contemporary clinical trials

Aims: The safety and efficacy of the novel selective cardiac myosin activator, omecamtiv mecarbil, in patients with heart failure with reduced ejection fraction (HFrEF) is tested in the Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure (GALACTIC‐HF) trial. Here we describe the baseline characteristics of participants in GALACTIC‐HF and how these compare with other contemporary trials. Methods and Results: Adults with established HFrEF, New York Heart Association functional class (NYHA) ≥ II, EF ≤35%, elevated natriuretic peptides and either current hospitalization for HF or history of hospitalization/ emergency department visit for HF within a year were randomized to either placebo or omecamtiv mecarbil (pharmacokinetic‐guided dosing: 25, 37.5 or 50 mg bid). 8256 patients [male (79%), non‐white (22%), mean age 65 years] were enrolled with a mean EF 27%, ischemic etiology in 54%, NYHA II 53% and III/IV 47%, and median NT‐proBNP 1971 pg/mL. HF therapies at baseline were among the most effectively employed in contemporary HF trials. GALACTIC‐HF randomized patients representative of recent HF registries and trials with substantial numbers of patients also having characteristics understudied in previous trials including more from North America (n = 1386), enrolled as inpatients (n = 2084), systolic blood pressure &lt; 100 mmHg (n = 1127), estimated glomerular filtration rate &lt; 30 mL/min/1.73 m2 (n = 528), and treated with sacubitril‐valsartan at baseline (n = 1594). Conclusions: GALACTIC‐HF enrolled a well‐treated, high‐risk population from both inpatient and outpatient settings, which will provide a definitive evaluation of the efficacy and safety of this novel therapy, as well as informing its potential future implementation

Extracorporeal Membrane Oxygenation for COVID-19-Associated Acute Respiratory Distress Syndrome: A Nationwide Analysis

Extracorporeal membrane oxygenation (ECMO) has been used for COVID-19-associated acute respiratory distress syndrome (ARDS). We aimed to elucidate the association between ECMO and mortality in patients with COVID-19-associated ARDS in the nationwide setting. United States National Inpatient Sample was used to identify mechanically ventilated adults for COVID-19 with ARDS. We divided them into three groups according to the use of ECMO (i.e., no-ECMO, venovenous [VV]-ECMO, and venoarterial [VA]-ECMO). The primary outcome was in-hospital mortality, while the secondary outcomes included the length of hospital stay (LOS) and the total costs during hospitalization. We performed a stepwise logistic regression, adjusting for baseline characteristics, comorbidities, and severity. We included 68 795 (mean age [SD]: 63.5 [0.1]), 3280 (mean age [SD]: 48.7 [0.5]), and 340 (mean age [SD]: 43.3 [2.1]) patients who received no-, VV-, and VA-ECMO, respectively. The logistic regression analysis did not show significant associations between the use of VV-/VA-ECMO and mortality (adjusted odds ratio with no-ECMO as reference [95% confidence interval]: 1.03 [0.86-1.24] and 1.18 [0.64-2.15], respectively). While LOS was longest with VV-ECMO, the total costs were highest with VA-ECMO. In conclusion, our study found no association between the use of ECMO and mortality of COVID-19-associated ARDS in the nationwide setting