Tahmeed Contractor

Left Atrial Appendage Closure in Atrial Fibrillation: A World without Anticoagulation?

Atrial Fibrillation (AF) is a common arrhythmia with an incidence that is as high as 10% in the elderly population. Given the large proportion of strokes caused by AF as well as the associated morbidity and mortality, reducing stroke burden is the most important part of AF management. While warfarin significantly reduces the risk of AF-related stroke, perceived bleeding risks and compliance limit its widespread use in the high-risk AF population. The left atrial appendage is believed to be the “culprit” for thrombogenesis in nonvalvular AF and is a new therapeutic target for stroke prevention. The purpose of this review is to explore the evolving field of percutaneous LAA occlusion. After briefly highlighting the risk of stroke with AF, problems with warfarin, and the role of the LAA in clot formation, this article discusses the feasibility and efficacy of various devices which have been developed for percutaneous LAA occlusion.

Statins and the reduction of sudden cardiac death: antiarrhythmic or anti-ischemic effect?

Sudden cardiac death is an important cause of cardiovascular mortality with the majority of cases occurring in low-risk groups. HMG-CoA reductase inhibitors (statins) have recently been shown to reduce the incidence of ventricular tachycardia (VT)/fibrillation (VF) and sudden cardiac death, and this has been attributed to their pleiotropic effects. However, it is unclear whether this occurs through an ‘indirect’ anti-ischemic or ‘direct’ antiarrhythmic effect. We systematically reviewed articles published on MEDLINE between January 1996 and December 2009 focusing on the reduction of VT/VF and sudden cardiac death by statins and the potential mechanisms. Studies reporting sudden cardiac death or VT/VF outcomes with statin use (n = 23) or the pathophysiology of sudden cardiac death reduction by statins (n = 19) were included. We found that statins have been shown to reduce VT/VF and sudden cardiac death only in subjects with underlying coronary artery disease or ischemic cardiomyopathy. No definite benefits were seen with statins in sudden cardiac death and VT/VF in patients with non-ischemic cardiomyopathy. There is insufficient evidence to point toward a benefit in populations at low risk for VT/VF. In conclusion, an anti-ischemic rather than a primary antiarrhythmic effect emerges as the likely mechanism of sudden cardiac death reduction with statins.

Is Statin Use Associated With Tendon Rupture? A Population-Based Retrospective Cohort Analysis.

Previous case reports and small studies have suggested that 3-hydroxy-3-methylglutaryl-CoA reductase inhibitors (HMG-CoA-Is) may increase the risk of tendon rupture. We conducted a population-based retrospective cohort evaluation to better assess this relationship. From approximately 800,000 enrollees of a private insurance database, those who were aged ⩽64 years with at least 1 year of continuous enrollment were selected. Exposure was defined as initiation of HMG-CoA-I after the beginning of the study period. Each exposed person was matched with 2 controls of similar age and gender. Baseline characteristics, including known risk factors for tendon rupture, were compared between exposed and control cohorts with fidelity to the studys matched design. After adjusting for differences in follow-up and baseline characteristics, incidence rate ratios for tendon rupture was assessed in HMG-CoA-I users and nonusers. A total of 34,749 exposed patients were matched with 69,498 controls. There was no difference in the occurrence of tendon ruptures in HMG-CoA-I users versus nonusers. The results remained unchanged after adjustment for age and gender. In conclusion, this population-based retrospective cohort evaluation suggests that use of HMG-CoA-Is as a group are not associated with tendon rupture.

Novel Oral Anticoagulants for Stroke Prevention in Patients with Atrial Fibrillation: Dawn of a New Era

Abstract Atrial fibrillation (AF) is an important cause of ischemic stroke and is the underlying cause of > 20% of all strokes, with increasing age being a risk factor. Until recently, warfarin was the only available oral anticoagulant used to decrease this risk in patients with AF. However, there are several disadvantages of warfarin use, such as the requirement for monitoring the international normalized ratio, its wide range of drug–food interactions, and its narrow therapeutic index. Thus, there has been a strong impetus for the development of newer oral anticoagulants with predictable pharmacokinetics that obviate the need for monitoring the international normalized ratio. The US Food and Drug Administration has approved a direct thrombin inhibitor (dabigatran) and 2 factor Xa inhibitors (rivaroxaban and apixaban) for stroke prevention in patients with non valvular AF. There are several other new oral anticoagulant agents on the horizon, including the factor Xa inhibitor edoxaban. This review article discusses the pharmacological properties, clinical trial data, and practical issues associated with the use of these novel oral anticoagulants.

Reduction in the Intensity Rate of Appropriate Shocks for Ventricular Arrhythmias With Statin Therapy

Higher rate of implantable cardioverter-defibrillator (ICD) shocks has been associated with increased mortality and morbidity. The aim of our study was to determine whether statins reduced the intensity rate of appropriate shock therapy for ventricular tachycardia/fibrillation in patients with an ICD placed for left ventricular systolic dysfunction. In this retrospective single center analysis, patients with an ejection fraction ≤35% who underwent ICD implantation were divided into treatment and control groups based on statin use. A zero-inflated negative binomial model was used to compare the intensity rate of appropriate ICD shocks between the 2 groups. Characteristics associated with shock-free follow-up were assessed using a stepwise logistic regression model. We found 699 patients eligible for inclusion, with 412 (59%) in the statin treatment group. The adjusted mean intensity rate of shocks was lower in patients on statin therapy (intensity rate ratio = 0.22; 95% confidence interval, 0.12-0.41; P < 0.001). Statin use was associated with a significantly higher probability of shock-free follow-up (odds ratio = 1.64; 95% confidence interval, 1.09-2.48; P = 0.019). In conclusion, statins reduced the intensity rate of appropriate shock therapy for ventricular tachycardia/fibrillation and increased probability of shock-free follow-up in patients with cardiomyopathy. Larger randomized trials are needed to confirm this relationship.

Statins reduce appropriate implantable cardioverter-defibrillator shocks in ischemic cardiomyopathy with no benefit in nonischemic cardiomyopathy

Statins have been hypothesized to decrease ventricular arrhythmias through a direct antiarrhythmic effect. Clinical studies have demonstrated a clear reduction only in populations with underlying ischemic heart disease. This study was designed to compare the effect of statins on appropriate shocks between ischemic and nonischemic cardiomyopathy. Patients with an ejection fraction 35% or less who received an implantable cardioverter–defibrillator and had follow-up for at least 1 month were included. The ischemic and nonischemic groups were divided into statin treatment and control subgroups and the occurrence of appropriate shocks was compared. The frequency of shocks was analyzed using negative binomial models to account for overdispersion of the “count” data (number of appropriate shocks) and an adjusted intensity rate ratio was calculated for statin use. A total of 676 patients were included, of which statins were used by 65% (329 of 506) of the ischemic and 42% (72 of 170) of the nonischemic groups. Occurrence of appropriate shocks was significantly reduced with statins in ischemic (13.4% vs 20.9%; relative risk 0.64, P = 0.028), but not in the patients with nonischemic cardiomyopathy. Similarly, although use of statins lowered the intensity rate of appropriate shocks in ischemic patients (intensity rate ratio, 0.23; 95% confidence interval, 0.12–0.47), no such benefit was noted in the nonischemic group (intensity rate ratio, 1.27; 95% confidence interval, 0.37–4.40). In conclusion, statins reduced the occurrence and frequency of appropriate shocks for ventricular arrhythmias in ischemic but not in nonischemic cardiomyopathy. Larger, randomized controlled trials are needed to confirm these findings.

Hormone Replacement Therapy–Induced Giant Aortic Thrombus

CLINICAL PRESENTATION A 54-year-old white woman presented with a 4-day history of postprandial, periumbilical abdominal pain. She was hypertensive and a 20 pack-year smoker. Her medications included nebivolol and combined estrogen/progesterone hormone replacement therapy (HRT) for hot flashes and mood swings for 8 years. On examination, bowel sounds were normal, and her abdomen was diffusely tender without guarding or rigidity. A contrast-enhanced computerized tomographic scan of the chest and abdomen revealed an extensive intraluminal filling defect in the aorta consistent with a nonobstructive aortic mural thrombus (Figure 1A). It was 16.5 cm in length and extended proximally from the initial part of the descending thoracic aorta (Figure 1B) to the origin of celiac axis distally (Figure 1C). There was no evidence of embolic disease in the abdominal viscera. She was started on aspirin and clopidogrel, and the hypercoagulable workup was negative. After an uneventful hospital course, she was discharged with strict instructions to stop smoking and discontinue HRT. Despite a significant decrease in the use of HRT, it is occasionally the only effective treatment for women with refractory postmenopausal symptoms.1 It has been known to predispose to both arterial and venous thrombosis, by increasing the levels of procoagulant factors (VII, X, XII, and XIII) and decreasing the levels of anticoagulant factors (protein S and antithrombin).2 Aortic thrombi usually occur in the setting of atherosclerosis, aortitis, aneurysm, dissection, or trauma.3 This is a rare case of a giant aortic thrombus resulting from HRT. Smoking and hypertension were other contributing factors. This serves to remind physicians about the potentially serious consequences of long-term HRT.

Value of Coronary Computed Tomography as a Prognostic Tool

Coronary computed tomography angiography (CCTA) has become an important part of our armamentarium for noninvasive diagnosis of coronary artery disease (CAD). Emerging technologies have produced lower radiation dose, improved spatial and temporal resolution, as well as information about coronary physiology. Although the prognostic role of coronary artery calcium scoring is known, similar evidence for CCTA has only recently emerged. Initial, small studies in various patient populations have indicated that CCTA‐identified CAD may have a prognostic value. These findings were confirmed in a recent analysis of the international, prospective Coronary CT Angiography Evaluation For Clinical Outcomes: An International Multicenter (CONFIRM) registry. An incremental increase in mortality was found with a worse severity of CAD on a per‐patient, per‐vessel, and per‐segment basis. In addition, age‐, sex‐, and ethnicity‐based differences in mortality were also found. Whether changing our management algorithms based on these findings will affect outcomes is unclear. Large prospective studies utilizing targeted management strategies for obstructive and nonobstructive CAD are required to incorporate these recent findings into our daily practice. Clin. Cardiol. 2012 DOI: 10.1002/clc.22003

Suction of the Left Internal Mammary Artery Graft Into a Pleural Drain Visualized by Computerized Tomography

A 69-year-old man with medically refractory 3-vessel coronary artery disease underwent sequential, minimally invasive coronary artery bypass grafting of the left internal mammary artery (LIMA) to the left anterior descending artery and first diagonal artery. The surgery was conducted off-pump and was uneventful. A pleural drain was placed on the left side at the end of the surgery. Postoperatively, the patient developed chest pain, and an ECG demonstrated new T-wave inversions (Figure 1, arrows) in comparison with his previous ECG (Figure 2 …

Uvular Necrosis as an Unusual Complication of Bronchoscopy Via the Nasal Approach

Bronchoscopy can cause post-procedural throat discomfort due to oropharyngeal irritation. We report a rare complication of bronchoscopy that resulted in similar symptoms. A 30-year-old man complained of severe throat discomfort a day after bronchoscopy. Examination revealed a swollen, elongated uvula. The lower half of the uvula was completely white, consistent with uvular necrosis. He was managed conservatively with topical lidocaine and antihistamines. At a follow-up examination 2 weeks later his symptoms had substantially improved and the necrosed uvula had separated, leaving a shortened uvula with an irregular border. Simple precautions taken during bronchoscopy can avoid this rare complication that causes persistent symptoms.