Echocardiography and valve replacement in the critically ill patient with acute rheumatic carditis

Immunologic and clinical correlations in rheumatic fever and rheumatic heart disease

The intimate relationship of Streptococcus pyogenes and rheumatic fever is well-established, but the precise pathogenesis of rheumatic fever and rheumatic heart disease continues to elude intense investigative efforts by students of the disease worldwide. Technologic advances in molecular biology, not thought possible two decades ago, have given additional insight into the immunologic aspects of the disease. On the clinical side echocardiography has proved to be a marvelous, non-invasive technique to evaluate cardiac anatomy and function. We are now able to gain a closer correlation of the clinical presentation and the autoimmune response. The increased understanding acquired both from the "bench" and the "bedside" are making this perplexing disease somewhat less mysterious. We seem tantalizingly close to grasping a complete understanding of the pathogenesis of rheumatic fever and rheumatic heart disease.

Aspects of active rheumatic carditis

Fulminating active rheumatic carditis has been observed for over 3 decades in this environment with no recent alteration in either the incidence or the pattern of presentation. Patients are black, seldom older than 20 years and are usually in their early teens but may occasionally be as young as five years. Heart failure is prevalent but occurs only when a haemodynamically important left-sided valve lesion supervenes. Regurgitation is the predominant valve lesion and involves principally the mitral valve. Mitral annular dilatation is the initial pathology and predisposes to lengthening--or rupture--of chordae tendineae and prolapse of the anterior leaflet. The resultant cardiac work-overload apparently perpetuates the rheumatic activity. Heart failure, whether caused by or associated with active rheumatic carditis, makes surgical management of the valve lesion mandatory as a life-saving measure. Mitral valve repair, rather than replacement, is the surgical procedure of choice but is not always practicable when the rheumatic activity is fulminant, significant aortic regurgitation associated or the surgeon relatively inexperienced. Aggressive medical therapy for heart failure, which should include vasodilator drugs, provides temporary improvement only. Contrary to ongoing doctrine, treatment with steroid drugs is neither life-saving nor beneficial. Varying degrees of left ventricular dysfunction are encountered pre-operatively and may be a sequel of the severe regurgitant valve lesion rather than of a rheumatic 'myocardial factor'.