Relation between myocardial contractility, hypertrophy and pump performance in patients with chronic aortic regurgitation: an echocardiographic study.
The aim of this study was to establish prognostic indices and to detect irreversible left ventricular dysfunction before aortic valve replacement in patients with chronic aortic regurgitation. Therefore, we determined the left ventricular pump/contractility relation (expressed as a ration between ejection fraction and peak systolic pressure/end-systolic volume), afterload mismatch (the relation between the ejection fraction and mean systolic wall stress) and the left ventricular end-diastolic radius/posterior wall thickness ratio in 52 patients with chronic aortic regurgitation by means of M-mode echocardiography. These indices were also calculated in 14 patients with idiopathic dilated cardiomyopathy and in 20 normal controls. The indices allowed separation of normals and patients with mild to moderate aortic insufficiency from patients with idiopathic dilated cardiomyopathy indicating that these indices could distinguish between patients with a reversible afterload mismatch and those with irreversible impaired muscle function. The 38 patients with severe aortic insufficiency showed a large overlap between normal and abnormal indices. Twelve of these patients had a pump/contractility index and a ratio between ejection fraction and wall stress similar to that found in patients with idiopathic dilated cardiomyopathy. All these patients, however, had a left ventricular end-diastolic radius/thickness ratio greater than 4 indicating "inadequate hypertrophy". Of these, 3 patients died perioperatively and 4 developed congestive heart failure within 12 months postoperatively. We conclude that an end-diastolic radius/thickness ratio greater than 4 is a sensitive but not a specific preoperative indicator of irreversible left ventricular damage in patients with chronic aortic regurgitation. This index is readily obtained preoperatively by M-mode echocardiography.
D000293:Adolescent; D000328:Adult; D001022:Aortic Valve Insufficiency / Q000503:physiopathology* / Q000601:surgery; D006332:Cardiomegaly / Q000503:physiopathology*; D002311:Cardiomyopathy, Dilated / Q000503:physiopathology; D002908:Chronic Disease; D004452:Echocardiography; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D011379:Prognosis; D013318:Stroke Volume