Oral anticoagulation is the mainstay of therapy for stroke prevention in patients with atrial fibrillation. Vitamin K antagonists such as warfarin reduce the risk of cardioembolic stroke by approximately two-thirds compared with no treatment, but are limited by their unpredictable anticoagulant effect and narrow therapeutic index. Warfarin therapy requires routine coagulation monitoring, which is inconvenient for patients and costly for the healthcare system. The limitations of the vitamin K agonists have spurred the development of new oral anticoagulants that selectively inhibit thrombin or factor Xa. The Randomized Evaluation of Long-Term Anticoagulation (RE-LY) trial of 18,113 patients with nonvalvular atrial fibrillation and at least one additional risk factor for stroke demonstrated that dabigatran etexilate given at a dose of 150 mg twice daily compared with warfarin, reduced the rate of stroke or systemic embolism by one-third with a similar rate of major bleeding, whereas dabigatran etexilate given at a dose of 110 mg twice daily compared with warfarin had a similar rate of stroke or systemic embolism and reduced the rate of major bleeding by one-fifth. Both doses of dabigatran etexilate reduced intracranial bleeding by approximately two-thirds compared with warfarin. Based on the results of the RE-LY trial, both the US FDA and Health Canada recently approved dabigatran etexilate for the prevention of stroke and systemic embolism in patients with nonvalvular atrial fibrillation.

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Background: While some studies indicate that permanent pacemaker implantation is associated with development of tricuspid regurgitation (TR), other studies indicate no association.Little is known about the impact of temporary lead insertion during ablation procedures, or whether therapy (CRT) prevents TR post-device implantation.Hypothesis: We hypothesized that permanent, but nottemporary endocardial leads, are associated with development of TR, and that CRT would prevent (physiologic) TR.Methods: We performed a retrospective study of consecutive patients who underwent first device or radiofrequency catheter ablation over a 12-month period at a single, tertiary academic center who underwent pre- and post-procedure echocardiography. Results: In the 89 patients in the device group, the degree of TR significantly increased ≥ 1 grade post-permanent lead implantation: 9 had less TR, 46 were unchanged, and 34 had more TR(p=0.005). TR increased in the 62 patients who underwent device implantation without CRT (p=0.005), but did not increase in the 27 patients with CRT (p=0.47). In the 66 patients in the ablation group, there was no significant change in TR post-ablation: 8 had less TR, 48 were unchanged, and 10 had more TR (p=0.31). Conclusion: Permanent endocardial lead implantation was associated with an increase in TR; however, patients who underwent device implantation with CRT did not have an increase in TR.Temporary lead insertion during ablation was not associated with changes in the degree of TR. A large, prospective study is needed to accurately define the incidence and exact mechanisms of permanent endocardial lead-related TR.

Foreword Information about a real patient is presented in stages (boldface type) to an expert (Dr Omid Salehian) who responds to the information, sharing his reasoning with the reader (regular type). A discussion by the authors follows.A 52-year-old woman is referred by her family physician to a general internist's clinic for assessment of a 3-month history of exertional dyspnea. She also reports a nonproductive nocturnal cough, night sweats, and an 18-lb weight loss over the preceding 3 months. The patient denies any history of chest pain, palpitations, presyncope, or syncope.The patient has a history of chronic obstructive pulmonary disease for which she was admitted to hospital 3 times in the last several months. Each time, she received a course of antibiotics and oral glucocorticoids, with no relief of her dyspnea. She reports no prior cardiac history, history of malignancies, or venous thromboembolic disease. Her home medications include salbutamol and tiotropium. She is a current smoker, with a 40-pack-year history, and denies alcohol intake or recreational drug use.Dr Salehian: Exertional dyspnea is a common complaint in patients presenting to emergency departments, general practitioners, internists, respirologists, and cardiologists. It has a very broad differential and could be attributable to a problem with the cardiovascular, respiratory, central nervous, or endocrine system. Furthermore, many patients with neoplastic or autoimmune disorders can present with dyspnea. The presence of constitutional symptoms and weight loss in a middleaged smoker is definitely concerning. Malignancy involving the lung, breast, or gastrointestinal system should be at the top of the differential diagnosis. One must also consider the possibility of hematologic malignancies such as lymphoma. Chronic systemic infections such as subacute bacterial endocarditis should be considered in the differential diagnosis. Collagen vascular disorders such as systemic lupus erythematosus or vasculitides could also have a similar presentation. Patient presentation (continued):On physical examination, she appears cachectic, weighing 51 kg at a height of 148 cm. Her blood pressure is 142/80 mm Hg and heart rate is 104 bpm; she has a regular respiratory rate of 24 breaths per minute and oxygen saturation of 93% on room air. Her temperature is 37.8°C. She is in mild respiratory distress, speaking in short sentences. Jugular venous pressure is 7 cm above the sternal angle with a positive abdominojugular reflux. Her carotid pulse is of normal volume and contour with no audible bruits. The apical impulse is normal in location and size. Auscultation reveals a normal S1 and S2 with a soft diastolic murmur heard best at the apex. No extra heart sounds are audible. There are coarse inspiratory crackles bilaterally at the lung bases. There is no pedal edema, and peripheral pulses are all palpable. There are no rashes, swollen joints, or palpable lymph nodes.On laboratory investigations, her total white blood cell count is 13 500 with 90% neutrophils, ...

About the AuthorsMichelle J. Haroun (left) is currently enrolled in the cardiology fellowship training program at McMaster University in Hamilton, Ontario. She received her undergraduate medical degree at McMaster University in 2009, and completed her Internal Medicine residency training at McMaster University in 2012. SummaryBackground: Previous studies have demonstrated higher referral rates for invasive procedures among patients admitted with acute coronary syndromes (ACS) to hospitals with catheterization facilities compared to those without. Studies have also reported underuse of evidence-based medical therapies and cardiac rehabilitation programs post myocardial infarction. We evaluated referral patterns for cardiac catheterization and use of secondary prevention strategies in current practice. Methods: We conducted a retrospective study of 397 patients with non-ST segment elevation ACS, comparing angiography referrals at a hospital with on-site catheterization facilities (Site A, n = 194) versus a hospital without (Site B, n = 203). We also recorded the use of secondary prevention strategies including discharge medications, referrals to smoking cessation programs and cardiac rehabilitation. Results: There was no significant effect of on-site angiography on the decision to manage patients invasively (adjusted OR for on-site angiography 1.49 95% CI 0.92-2.44, p = .11), or wait times for cardiac catheterization (Site A 1.9 days vs. Site B 2.2 days, difference −0.3 days, 95% CI −0.83 to 0.55, p = .70). However, at the time of hospital discharge, less than 70% of patients were prescribed dual antiplatelet therapy and only 13% of patients were referred for cardiac rehabilitation. Conclusion: These observations suggest that in contemporary practice in a Southern Ontario community, the availability of on-site percutaneous coronary intervention does not influence referral rates or wait times for cardiac catheterization. However we did observe significant underuse of cardiac rehabilitation programs and certain medical therapies. This suggests that despite improvements in access to invasive procedures, there remain important gaps in secondary prevention of coronary artery disease, which represent opportunities to improve quality of care in these patients. C a n a d i a n J o u r n a l o f G e n e r a l I n t e r n a l M e d i c i n e V o l u m e 9 , I s s u e 3 , 2 0 1 4