title: Prevalence and clinical characteristics of nondilated cardiomyopathy and the effect of atrial fibrillation.
abstract: The treatment of patients with chronic heart failure and those with asymptomatic left ventricular (LV) dysfunction has focused primarily on patients with LV enlargement and a low ejection fraction (EF). Little attention has been paid to those with a normal chamber size and a low EF. We sought to examine the LV geometry and clinical characteristics in such patients with nondilated cardiomyopathy. Of 3,350 transthoracic echocardiograms performed during a 6-month period, 696 showed an EF of < or =0.45. The patients with an end-diastolic diameter of >56 mm, regional wall motion abnormalities, or valvular disease were excluded. Of the 696 patients, 98 met these criteria, and their medical records were reviewed. The average age was 71 +/- 14 years, and 56% were men. Common co-morbidities included hypertension in 52% and atrial fibrillation (AF) in 43%. Only 22% had disabling cardiac symptoms (functional class III or greater). The average end-diastolic dimension was 49 +/- 5 mm, and the EF was 34 +/- 8%. LV hypertrophic remodeling was present in 53%. A second echocardiogram (422 +/- 177 days after the baseline study) was available for 54 patients. The chamber size was unchanged, but the EF had increased from 33 +/- 8% to 40 +/- 14% (p <0.01). The improvement in EF was seen in the group with AF (33 +/- 6% to 44 +/- 15%, p <0.01) but not in those with normal sinus rhythm (33 +/- 9% to 37 +/- 12%, p = NS). In conclusion, 14% of patients with an EF of < or =0.45 had nondilated cardiomyopathy, often with LV hypertrophic remodeling and/or AF. An improvement in LV function can be expected in many patients with nondilated cardiomyopathy, particularly those with AF.
authors.affiliation: Department of Cardiovascular Medicine, Lahey Clinic Medical Center, Burlington, Massachusetts.
authors.forename: Alexander
authors.initials: A
authors.lastname: Doumas
authors.forename: Timothy S
authors.initials: TS
authors.lastname: Draper
authors.forename: Edgar C
authors.initials: EC
authors.lastname: Schick
authors.forename: William H
authors.initials: WH
authors.lastname: Gaasch
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000150:complications*; D009202:Cardiomyopathies / Q000150:complications* / Q000000981:diagnostic imaging / Q000503:physiopathology; D004452:Echocardiography; D005260:Female; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology; D008297:Male; D013318:Stroke Volume; D016277:Ventricular Function, Left; D020257:Ventricular Remodeling