Atrial Hypertrophy Case Study

1. Pastor BH, Forte AL. Idiopathic enlargement of the right atrium. Am J Cardiol 1961;8:513–8. [PubMed]

2. Binder TM, Rosenheck R, Frank H, et al. Congenital malformations of the right atrium and coronary sinus. Chest 2000;117:1740–8. [PubMed]

3. Jenni R , Goebel N, Schneider L, et al. [Idiopathic familial right atrial dilatation]. Schweiz Med Wochenschr 1981;111:1565–72. [PubMed]

4. Takahashi M , Nakagawa Y, Ogawa N, et al. [Familial idiopathic enlargement of the right atrium]. Kokyu To Junkan 1988;36:573–6. [PubMed]

5. Blondheim DS, Klein R, Plich M, et al. Familial idiopathic dilatation of the right atrium with complete atrio-ventricular block: a new syndrome? Cardiology 2000;94:224–6. [PubMed]

6. Sumner RG, Phillips JH, Jacoby WJ Jr, et al. Idiopathic enlargement of the right atrium. Circulation 1965;32:985–91. [PubMed]

7. Kobza R , Oechslin E, Pretre R, et al. Enlargement of the right atrium: diverticulum or aneurysm. Eur J Echocardiogr 2003;4:223–5. [PubMed]

8. Reinhardt-Owlya L , Sekarski N, Hurni M, et al. [Idiopathic dilatation of the right atrium simulating Ebstein’s anomaly: apropos of a case diagnosed in utero]. Arch Mal Coeur Vaiss 1998;91:645–9. [PubMed]

9. Asayama J , Matsuura T, Endo N, et al. Idiopathic enlargement of the right atrium. Am J Cardiol 1977;40:620–3. [PubMed]

10. Arima M , Kanoh T, Okazaki S, et al. Clinical manifestation and survival of patients with idiopathic bilateral atrial dilatation. Intern Med 1999;38:112–8. [PubMed]

11. Kabala JE, Wilde P. Measurement of heart size in the anteroposterior chest radiograph. Br J Radiol 1987;60:981–6. [PubMed]

12. DuBois D , DuBois EF. A formula to estimate the approximate surface area if height and weight be known. Arch Intern Med 1916;17:863–71. [PubMed]

13. Bommer W , Weinert L, Neumann A, et al. Determination of right atrial and right ventricular size by two-dimensional echocardiography. Circulation 1979;60:91–100. [PubMed]

14. Anon. Appendix A. Normal cross-sectional echocardiographic measurements. In: Weymann AE, ed. Principles and practice of echocardiography. 2nd ed. Philadelphia: Lippincott Williams and Wilkins, 1994:1289–98.

15. Blaysat G , Villain E, Marcon F, et al. [Prognosis and outcome of idiopathic dilatation of the right atrium in children: a cooperative study of 15 cases]. Arch Mal Coeur Vaiss 1997;90:645–8. [PubMed]

RISK FACTORS FOR THROMBOEMBOLIC STROKE

Risk factors for TE stroke in persons with AF include age,96,170–173 diabetes mellitus,171 echocardiographic left atrial enlargement,174,175 echocardiographic LV systolic dysfunction,173,175,176 echocardiographic LV hypertrophy,173,174 ECAD,108 history of CHF,171,176,177 prior MI,170,171,174,178 hypertension,171,174,176,177 mitral annular calcium,170,179 prior arterial thromboembolism, rheumatic mitral stenosis,173,174 and women older than 75 years.176Table 45-6 lists independent risk factors for new TE stroke in 312 persons with chronic AF, mean age 84 years.

In the SPAF Study involving persons, mean age 67 years, with nonrheumatic AF, recent CHF (within 3 months), a history of hypertension, prior arterial thromboembolism, echocardiographic LV systolic dysfunction, and echocardiographic left atrial enlargement were independently associated with new TE events.175,177 The incidence of new TE events was 18.6% per year if three or more risk factors were present, 6.0% per year if 1 or 2 risk factors were present, and 1.0% per year if none of these risk factors was present.175 In the SPAF III Study, persons, mean age 72 years, were considered to be at high risk for developing TE stroke if they had either a previous thromboembolism, CHF, or abnormal LV systolic function, a systolic blood pressure higher than 160 mm Hg, or the person was a woman older than 75 years of age.176

Antithrombotic therapy

Prospective, randomized studies have shown that warfarin was effective in reducing the incidence of TE stroke in persons with nonvalvular AF.171,176,180–186 Analysis of pooled data from five randomized controlled trials demonstrated that warfarin decreased the incidence of new TE stroke by 68% and was more effective than aspirin in decreasing TE stroke.171 Nonrandomized observational data from an elderly population mean age 83 years, found that 141 persons with chronic AF treated with oral warfarin to achieve an INR between 2.0 and 3.0 (mean INR was 2.4) had a 67% decrease in new TE stroke compared with 209 persons with chronic AF treated with oral aspirin.187 Compared with aspirin, warfarin caused a 40% decrease in new TE stroke in persons with prior stroke, a 31% reduction in new TE stroke in persons with no prior stroke, a 45% decrease in new TE stroke in persons with an abnormal LV ejection fraction, and a 36% reduction in new TE stroke in persons with a normal LV ejection fraction.187

At 1.1-year follow-up in the SPAF III Study, persons with nonvalvular AF considered to be at high risk for developing TE stroke randomized to therapy with oral warfarin to achieve an INR between 2.0 and 3.0 had a 72% decrease in ischemic stroke or systemic embolism compared with persons randomized to therapy with oral aspirin 325 mg daily plus oral warfarin to achieve an INR between 1.2 to 1.5.176 Adjusted-dose warfarin caused an absolute decrease in ischemic stroke or systemic embolism of 6.0% per year.176 In the Second Copenhagen Atrial Fibrillation, Aspirin, Anticoagulation (AFASK) Study, low-dose warfarin plus aspirin was also less effective in decreasing stroke or a systemic TE event in persons with AF (7.2% after 1 year) than was adjusted-dose warfarin to achieve an INR between 2.0 to 3.0 (2.8% after 1 year).188

Analysis of pooled data from five randomized controlled trials showed that the annual rate of major hemorrhage was 1.0% for the control group, 1.0% for the aspirin group, and 1.3% for the warfarin group.171 The incidence of major hemorrhage in persons taking adjusted-dose warfarin to achieve an INR of 2.0 to 3.0 in the SPAF III Study (mean age 72 years) was 2.1%.176 In the Second Copenhagen AFASK Study, the incidence of major hemorrhage in persons, mean age 73 years, was 0.8% per year for persons taking adjusted-dose warfarin to achieve an INR between 2.0 and 3.0 and 1.0% per year for persons treated with aspirin, 300 mg daily.188 The incidence of major hemorrhage in elderly persons, mean age 83 years, was 4.3% (1.4% per year) for persons with chronic AF taking warfarin to maintain an INR between 2.0 and 3.0 and 2.9% (1.0% per year) for persons with chronic AF treated with aspirin, 325 mg daily.187

In the SPAF III Study, 892 persons, mean age 67 years, at low risk for developing new TE stroke were treated with oral aspirin, 325 mg daily.189 Mean follow-up was 2 years. The incidence of new ischemic stroke or systemic embolism (primary events) was 2.2% per year.189 The incidence of new ischemic stroke or systemic embolism was 3.6% in persons with a history of hypertension and 1.1% in persons without a history of hypertension.189

In the Anticoagulation and Risk Factor in Atrial Fibrillation Study, women off warfarin had significantly higher annual rates of thromboembolism (3.5%) than men (1.8%).190 Warfarin was associated with significantly lower adjusted TE rates for both women (60% reduction) and men (40% reduction) with similar annual rates of major bleeding (1.0% and 1.1%, respectively).190

The Atrial Fibrillation Clopidogrel Trial with Irbersartan for the Prevention of Vascular Events (ACTIVE W) demonstrated in patients with AF that the annual risk of first occurrence of stroke, noncentral nervous system systemic embolus, MI, or vascular death was 3.93% in 3371 patients randomized to warfarin to maintain an INR between 2.0 and 3.0, and 5.60% in 3335 patients randomized to clopidogrel 75 mg daily plus aspirin 75 to 100 mg daily, with a 44% significant decrease in the primary outcome attributed to warfarin.191 The incidence of major bleeding was insignificantly (10%) higher in patients treated with clopidogrel plus aspirin than in persons treated with warfarin.191

On the basis of the available data, elderly persons with chronic or paroxysmal AF who are at high risk for developing TE stroke or who have a history of hypertension and who have no contraindications to anticoagulation therapy should receive long-term oral warfarin to achieve an INR of 2.0 to 3.0.157,192 Hypertension must be controlled. Whenever the person has a prothrombin time taken, the blood pressure should also be checked. The physician prescribing the dose of oral warfarin should be aware of the numerous drugs that potentiate the effect of warfarin causing an increased prothrombin time and risk of bleeding.35 Elderly persons with AF who are at low risk for developing TE stroke or who have contraindications to therapy with long-term oral warfarin should be treated with aspirin 325 mg orally daily.

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