Journal of the American Society of Echocardiography : official publication of the American Society of Echocardiography
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J Am Soc Echocardiogr · Dec 2000
Case ReportsEntrapment of subvalvular mitral tissue causing intermittent failure of a St Jude mitral prosthesis.
Frequently portions of the mitral valve and sub-valvular apparatus are left intact during mitral valve replacement to help preserve left ventricular function. We describe a patient with paroxysmal congestive heart failure caused by intermittent entrapment of the subvalvular apparatus in the prosthesis, preventing complete valve closure.
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J Am Soc Echocardiogr · Dec 2000
Sublingual nitroglycerin delays arterial wave reflections despite increased aortic "stiffness" in patients with hypertension: a Doppler echocardiography study.
Venodilatation with consequent reduction in left ventricular filling and end-diastolic wall stress is an important mechanism for the beneficial effects of nitroglycerin in ischemic heart disease and in left ventricular failure. The effects of sublingual nitroglycerin on arterial pulsatile hemodynamics are less well defined. Doppler echocardiography and the calibrated subclavian artery pulse tracing were used to assess hemodynamics in subjects with sustained arterial hypertension (n = 25) before and 5 to 10 minutes after sublingual deposition of 0.5 mg glyceryl trinitrate. ⋯ Peripheral resistance tended to decrease (4%, P =.06). Thus, in subjects with sustained hypertension, sublingual nitroglycerin dilates peripheral, predominantly muscular arteries with a subsequent delayed return of reflected pressure waves. Reflex activation of the sympathetic nervous system with consequent increased acceleration of left ventricular ejection seems to counteract the effect of reduced mean arterial pressure (distending pressure) with respect to the "stiffness" of the aorta.
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J Am Soc Echocardiogr · Dec 2000
Case ReportsThe value of repeat transesophageal echocardiography in the evaluation of embolism from the aorta.
Transesophageal echocardiography (TEE) is now widely used in the evaluation of patients with unexplained stroke or transient ischemic attack, in part to exclude the presence of protruding aortic arch atheromas. We report two cases in which repeated TEE revealed an aortic clot not seen on the earlier transesophageal echocardiogram performed immediately after embolization. These cases illustrate the dynamic nature of aortic thrombus and the role of TEE in its diagnosis.