Top 10 Cardiology Articles of the week (02.03.2015-08.03.2015)
1. Low-Level Transcutaneous Electrical Vagus Nerve Stimulation (LLTS) Suppresses Atrial Fibrillation
Conclusion: LLTS suppresses AF and decreases inflammatory cytokines in patients with paroxysmal AF. The results support the emerging paradigm of neuromodulation to treat AF.
2. Implantable Cardioverter-Defibrillator Therapy in Brugada Syndrome:A 20-Year Single-Center Experience
Background: Patients with Brugada syndrome and aborted sudden cardiac death or syncope have higher risks for ventricular arrhythmias (VAs) and should undergo implantable cardioverter-defibrillator (ICD) placement. Device-based management of asymptomatic patients is controversial. ICD therapy is associated with high rates of inappropriate shocks and device-related complications.
Objectives: The objective of this study was to investigate clinical features, management, and long-term follow-up of ICD therapy in patients with Brugada syndrome.
Methods: Patients presenting with spontaneous or drug-induced Brugada type 1 electrocardiographic findings, who underwent ICD implantation and continuous follow-up at a single institution, were eligible for this study.
Results A total of 176 consecutive patients were included. During a mean follow-up period of 83.8 ± 57.3 months, spontaneous sustained VAs occurred in 30 patients (17%). Eight patients (4.5%) died. Appropriate ICD shocks occurred in 28 patients (15.9%), and 33 patients (18.7%) had inappropriate shocks. Electrical storm occurred in 4 subjects (2.3%). Twenty-eight patients (15.9%) experienced device-related complications. In multivariate Cox regression analysis, aborted sudden cardiac death and VA inducibility on electrophysiologic studies were independent predictors of appropriate shock occurrence.
Conclusions: ICD therapy was an effective strategy in Brugada syndrome, treating potentially lethal arrhythmias in 17% of patients during long-term follow-up. Appropriate shocks were significantly associated with the presence of aborted sudden cardiac death but also occurred in 13% of asymptomatic patients. Risk stratification by electrophysiologic study may identify asymptomatic patients at risk for arrhythmic events and could be helpful in investigating syncope not related to VAs. ICD placement is frequently associated with device-related complications, and rates of inappropriate shocks remain high regardless of careful device programming.
The lack of consistent definitions and nomenclature across clinical trials of novel devices, drugs, or biologics poses a significant barrier to accrual of knowledge in and across peripheral artery disease therapies and technologies. Recognizing this problem, the Peripheral Academic Research Consortium, together with the U.S. Food and Drug Administration and the Japanese Pharmaceuticals and Medical Devices Agency, has developed a series of pragmatic consensus definitions for patients being treated for peripheral artery disease affecting the lower extremities. These consensus definitions include the clinical presentation, anatomic depiction, interventional outcomes, surrogate imaging and physiological follow-up, and clinical outcomes of patients with lower-extremity peripheral artery disease. Consistent application of these definitions in clinical trials evaluating novel revascularization technologies should result in more efficient regulatory evaluation and best practice guidelines to inform clinical decisions in patients with lower extremity peripheral artery disease.
4. Long-Term Survival Benefit of Revascularization Compared With Medical Therapy in Patients With Coronary Chronic Total Occlusion and Well-Developed Collateral Circulation
Objectives: The purpose of this study was to compare the long-term clinical outcomes of patients with chronic total occlusion (CTO) and well-developed collateral circulation treated with revascularization versus medical therapy.
Background: Little is known about the clinical outcomes and optimal treatment strategies of CTO with well-developed collateral circulation.
Methods: 2,024 consecutive patients with at least 1 CTO detected on coronary angiogram were screened. Of these, data was analyzed from 738 patients with Rentrop 3 grade collateral circulation who were treated with medical therapy alone (n = 236), coronary artery bypass grafting (n = 170) or percutaneous coronary intervention (n = 332; 80.1% successful). Patients who underwent revascularization and medical therapy (revascularization group, n = 502) were compared with those who underwent medical therapy alone (medication group, n = 236) in terms of cardiac death and major adverse cardiac events (MACE), defined as the composite of cardiac death, myocardial infarction, and repeat revascularization.
Results: During a median follow-up duration of 42 months, multivariate analysis revealed a significantly lower incidence of cardiac death (hazard ratio [HR]: 0.29; 95% confidence interval [CI]: 0.15 to 0.58; p < 0.01) and MACE (HR: 0.32; 95% CI: 0.21 to 0.49; p < 0.01) in the revascularization group compared with the medication group. After propensity score matching, the incidence of cardiac death (HR: 0.27; 95% CI: 0.09 to 0.80; p = 0.02) and MACE (HR: 0.44; 95% CI: 0.23 to 0.82; p = 0.01) were still significantly lower in the revascularization group than in the medication group.
Conclusions In patients with coronary CTO and well-developed collateral circulation, aggressive revascularization may reduce the risk of cardiac mortality and MACE.
A unifying definition of what constitutes high-risk percutaneous coronary intervention remains elusive. This reflects the existence of several recognized patient, anatomic, and procedural characteristics that, when combined, can contribute to elevating risk. The relative inability to withstand the adverse hemodynamic sequelae of dysrhythmia, transient episodes of ischemia-reperfusion injury, or distal embolization of atherogenic material associated with coronary intervention serve as a common thread to tie this patient cohort together. This enhanced susceptibility to catastrophic hemodynamic collapse has triggered the development of percutaneous cardiac assist devices such as the intra-aortic balloon pump, Impella (Abiomed Inc., Danvers, Massachusetts), TandemHeart (CardiacAssist, Inc., Pittsburgh, Pennsylvania), and extracorporeal membranous oxygenation to provide adjunctive mechanical circulatory support. In this state-of-the-art review, we discuss the physiology underpinning their application. Thereafter, we examine the results of several randomized multicenter trials investigating their use in high-risk coronary intervention to determine which patients would benefit most from their implantation and whether there is a signal to delineate whether they should be used in an elective pre-procedure, standby, rescue, or routine post-procedure fashion.
Calcification of the thoracic aorta is often associated with valvular and coronary calcification, reflecting an underlying atherosclerotic process. It has been found to be associated with an increased rate of mortality and cardiovascular disease. Porcelain aorta (PA) is extensive calcification of the ascending aorta or aortic arch that can be completely or near completely circumferential. This entity is rare in the general population, but it has an increasing incidence in older patients and in patients with coronary artery disease (CAD) or aortic stenosis (AS). The clinical relevance is based on the fact that it can complicate surgical aortic valve replacement (SAVR) for the treatment of severe AS by preventing safe access via the ascending aorta. PA is associated with increased morbidity and mortality, especially as a result of increased perioperative stroke risk. Recently, transcatheter aortic valve replacement (TAVR) has emerged as a less invasive and feasible treatment option in patients at high risk for conventional SAVR. In some series, ≈20% (5%–33%) of patients undergoing TAVR were diagnosed with PA. Inconsistencies in the definition and the use of different diagnostic modalities contribute to this wide range of PA prevalence. This article reviewed the available published data to seek a consistent, clinically relevant definition based on contemporary imaging, a firm understanding of the pathogenesis and associations, and the clinical implications of this disease entity.
7.Digoxin use in patients with atrial fibrillation and adverse cardiovascular outcomes: a retrospective analysis of the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET AF)
Conclusion: Digoxin treatment was associated with a significant increase in all-cause mortality, vascular death, and sudden death in patients with AF. This association was independent of other measured prognostic factors, and although residual confounding could account for these results, these data show the possibility of digoxin having these effects. A randomised trial of digoxin in treatment of AF patients with and without heart failure is needed.
8.Diagnosis of atrial fibrillation after stroke and transient ischaemic attack: a systematic review and meta-analysis
Background:Among patients with atrial fibrillation, the risk of stroke is highest for those with a history of stroke; however, oral anticoagulants can lower the risk of recurrent stroke by two-thirds. No consensus has been reached about how atrial fibrillation should be investigated in patients with stroke, and its prevalence after a stroke remains uncertain. The authors did a systematic review and meta-analysis to estimate the proportion of patients newly diagnosed with atrial fibrillation after four sequential phases of cardiac monitoring after a stroke or transient ischaemic attack.
Methods: The authors searched PubMed, Embase, and Scopus from 1980 to June 30, 2014 and included studies that provided the number of patients with ischaemic stroke or transient ischaemic attack who were newly diagnosed with atrial fibrillation. They stratified cardiac monitoring methods into four sequential phases of screening: phase 1 (emergency room) consisted of admission electrocardiogram (ECG); phase 2 (in hospital) comprised serial ECG, continuous inpatient ECG monitoring, continuous inpatient cardiac telemetry, and in-hospital Holter monitoring; phase 3 (first ambulatory period) consisted of ambulatory Holter; and phase 4 (second ambulatory period) consisted of mobile cardiac outpatient telemetry, external loop recording, and implantable loop recording. The primary endpoint was the proportion of patients newly diagnosed with atrial fibrillation for each method and each phase, and for the sequential combination of phases. For each method and each phase, they estimated the summary proportion of patients diagnosed with post-stroke atrial fibrillation using random-effects meta-analyses.
Findings: The systematic review returned 28 290 studies, of which 50 studies (comprising 11 658 patients) met the criteria for inclusion in the meta-analyses. The summary proportion of patients diagnosed with post-stroke atrial fibrillation was 7·7% (95% CI 5·0–10·8) in phase 1, 5·1% (3·8–6·5) in phase 2, 10·7% (5·6–17·2) in phase 3, and 16·9% (13·0–21·2) in phase 4. The overall atrial fibrillation detection yield after all phases of sequential cardiac monitoring was 23·7% (95% CI 17·2–31·0).
Interpretation: By sequentially combining cardiac monitoring methods, atrial fibrillation might be newly detected in nearly a quarter of patients with stroke or transient ischaemic attack. The overall proportion of patients with stroke who are known to have atrial fibrillation seems to be higher than previously estimated. Accordingly, more patients could be treated with oral anticoagulants and more stroke recurrences prevented.
9.Comparative Outcomes of Catheter-Directed Thrombolysis Plus Anticoagulation Versus Anticoagulation Alone in the Treatment of Inferior Vena Caval Thrombosis
Conclusions—There has been a steady increase in the use of CDT in the treatment of patients with inferior vena cava thrombosis in the United States. This observational study showed no significant difference in mortality between CDT versus anticoagulation alone; however, the bleeding events and resource utilization were higher in the CDT group. Adequately powered randomized controlled trials are needed in this area.
DES implantation was not associated with higher adverse events after NCS. Moreover, the incidence of adverse events following NCS was lower when NCS was performed >90 days post-DES implantation suggesting that it may not be necessary to wait until 12 months post PCI with DES before NCS.