tailieunhanh - SURGICAL OPTIONS FOR THE TREATMENT OF HEART FAILURE - PART 3
Giới thiệu về tim mạch và bác sĩ phẫu thuật tim thường xuyên phải quyết định khi nào là thích hợp để cung cấp can thiệp phẫu thuật sớm để ngăn chặn sự thỏa hiệp của trái fiuiction ventncular trom tổn thương regurgitant của van động mạch chủ hoặc van hai lá. | 3. Valve surgery for regurgitant lesions of the AORTIC OR MITRAL VALVES IN ADVANCED LEFT VENTRICULAR DYSFUNCTION Robert o. Bonow and Roy G. Masters Introduction Cardiologists and cardiac surgeons frequently must decide when it is appropriate to offer early surgical intervention to prevent compromise of left ventricular function from regurgitant lesions of the aortic or mitral valve. Both aortic and mitral regurgitation place a volume load on the left ventricle leading to dilatation and eventually impairment of left ventricular systolic function. This chapter however deals with the opposite issue that of late surgical intervention after deterioration of left ventricular systolic function has occurred and reached advanced levels. Important questions to consider include 1 whether surgical intervention is contraindicated once advanced left ventricular dysfunction has become established 2 whether the risks of surgery are too high in this setting and 3 whether even after successful surgery improvements in left ventricular function symptoms or survival can realistically be anticipated. A word should also be said about the medical management of regurgitant lesions with left ventricular dysfunction. Vasodilators and angiotensin converting enzyme ACE inhibitors have become popular in the treatment of left ventricular volume overload on the premise that afterload reduction is theoretically reasonable as a means to decrease regurgitant volume and improve forward stroke volume. These should result in reductions in left ventricular end-diastolic volume and wall stress and preservation of systolic function. Data indeed suggest a possible role for nifedipine in favorably influencing the long-term natural history of asymptomatic patients with normal left ventricular systolic function by resulting in a more gradual rate of development of symptoms or ventricular dysfunction 1 2 These data however do not pertain to patients with symptoms related to advanced left ventricular .
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