Search

Byline: Annick Haouzi, Hans Berglund, Peter C.D. Pelikan, Gerald Maurer, Robert J. Siegel Abstract: Although prophylactic treatment with [beta]-blockers is used to retard aortic root dilatation in Marfan syndrome, it is not effective in all patients. To assess the effects of [beta]-adrenergic blockade on the aorta's elastic properties, aortic stiffness index and distensibility were calculated in 13 patients with Marfan syndrome and 10 control subjects before and after [beta]-adrenergic blockade. At baseline, patients with Marfan syndrome had a significantly increased stiffness index and decreased distensibility. After [beta]-adrenergic blockade, 8 patients with Marfan syndrome developed stiffness indexes and distensibility values that were closer to normal, whereas these variables deteriorated in 5 patients. Thus the benefit of [beta]-adrenergic blockade in Marfan syndrome may be the reduction in pulse pressure and myocardial contractility and also promotion of the elastic properties of the aorta. Moreover, the differential responses of aortic mechanics (normalizing or worsening) to [beta]-adrenergic blockade may possibly have implications for the prognosis in these patients. (Am Heart J 1997;133:60-3.) Author Affiliation: Vandoeuvre-les-Nancy, France, Los Angeles and Santa Monica, Calif., and Vienna, Austria Article History: Received 13 November 1995; Accepted 11 March 1996 Article Note: (footnote) [star] From the aDepartment of Cardiovascular Surgery, HA[acute accent]pital de Brabois; b Division of Cardiology, Cedars-Sinai Medical Center, and University of California, Los Angeles School of Medicine; the cPacific Heart Institute, St. Johns Hospital and Heart Center; and d Cardiology Department, University of Vienna., [star][star] Supported by grants from the Swedish Society of Medicine, Wenner-Gren Center Foundation, Swedish Institute, Einar Belven Foundation, Herbert Stein MD Research Fund, and Lee E. Siegel MD Memorial Fund, Western Cardiac Foundation., a Reprint requests: Hans Berglund, MD, Division of Cardiology, Room 5335, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048., aa 4/1/75315

It is estimated that in 1991, 75,000 cases of acquired immune deficiency syndrome (AIDS) will be diagnosed in the US, and there will be 60,000 deaths. By 1992, the number of cases of AIDS is estimated to be more than 365,000, resulting in 200,000 deaths. Heart and circulatory system complications are common with AIDS, although they are not usually fatal. Heart conditions commonly associated with AIDS are: dilated cardiomyopathy (disease of the heart muscle), myocarditis (inflammation of the heart muscle), pericarditis (inflammation of the sac surrounding the heart) and other diseases of the pericardium, endocarditis (inflammation of the membrane lining the heart), and complications arising from cancer, such as Kaposi's sarcoma, which initially affects the skin, but can spread to other parts of the body. A diagnosis of dilated cardiomyopathy using echocardiography (noninvasive imaging) indicates a poor prognosis, with half of these patients dying within six months. However, these patients often respond to conventional drug therapy for congestive heart failure. Noninvasive studies have demonstrated cardiac abnormalities in 30 percent to 40 percent of adult patients, and up to 26 percent of pediatric AIDS patients. Most AIDS patients have no definitive symptoms of heart disease. Pulmonary (lung) failure causes more than half of AIDS deaths, but as more effective therapies are developed, there will be fewer deaths from pulmonary failure, and heart diseases will become more common. A better understanding of the causes, as well as more accurate diagnosis, are important in treating heart diseases in AIDS patients. (Consumer Summary produced by Reliance Medical Information, Inc.)

Angiography, serial X-raying of blood vessels after injection of a dye, can show the contours of blood vessels, while angioscopy, which involves threading a microscopic tube into vessels, and ultrasound imaging can provide information about abnormalities of vessel surfaces and walls. These techniques are not usually used together. Two cases are reported in which all three methods were used before and after percutaneous transluminal angioplasty (PTA), in which a balloon catheter is threaded into a constricted blood vessel and then inflated. The first patient was a 72-year-old man with claudication (leg pain during activity) who had no pulse in the right foot. Angiography showed 75 percent narrowing of a leg artery due to atherosclerosis, while angioscopy showed a clot. The clot was aspirated. Ultrasound confirmed atherosclerotic narrowing and suggested calcification of the area, so that high pressures would be needed during balloon inflation. Following inflation, only a 25 percent narrowing remained, and angioscopy and ultrasound showed tearing of the arterial lining. The second case was a 75-year-old man with similar symptoms. All three imaging techniques indicated the patient had an atherosclerotic plaque next to an area of complete blockage. Following catheter inflation, the area was found to be 65 percent constricted, and angioscopy and ultrasound but not angiography indicated that the plaque had a disrupted surface. The study demonstrates that angiography is best for analysis of an entire area of blood vessels, while angioscopy is best for evaluating the vessel surface, and ultrasound provides information about the vessel wall. The last two techniques are not yet easy to use, but led to alterations in treatment in a fourth of the cases where they were employed. Use of angiography with the other techniques should lead to improved patient treatment and should improve understanding of disease processes in blood vessels. (Consumer Summary produced by Reliance Medical Information, Inc.)

Blood clotting is an essential protective mechanism. However, thrombi (immobile clots) and emboli (formed clots that travel through the cardiovascular system before lodging) may be life-threatening; pulmonary embolism (in which a clot lodges in the pulmonary artery) is the third largest cause of death in the US. Thrombolytic (clot-dissolving) therapy with heparin or proteins like streptokinase have been effective in some patients, but can cause bleeding and thus these agents can often not be used. Ultrasound has been used to disrupt thrombi, but the process has not been well-characterized. The effectiveness of ultrasound on disrupting clots was studied in terms of clot age, ultrasound probe length, size of breakdown particles, and role of thrombolysis. Ultrasound was effective within 60 minutes of use on clots that were one to seven days old. The time needed for clot disruption increased as the length of the ultrasound probe wire increased. Almost all particulates produced by ultrasound clot disruption were smaller than blood cells, and thus were unlikely to cause clots themselves. Streptokinase had little effect on clot breakdown, and ultrasound disruption was related to mechanical breakdown of the structure, rather than to the biochemical aspect of thrombolysis (the endogenous mechanism for clot breakdown). The study suggests that ultrasound may be an effective technique for disruption of human blood clots without the complications associated with thrombolysis. (Consumer Summary produced by Reliance Medical Information, Inc.)