University Times

Non-invasive techniques to visualize heart disease show importance of pre-menopause risk factors

Using electron beam computed tomography (EBCT) to visualize early heart disease, University researchers have found that pre-menopausal risk factors strongly predict which women will develop coronary artery disease five to eight years after menopause.

The study is the first to combine EBCT scans of the aorta and coronary arteries with carotid ultrasounds to assess the extent of heart disease in living people, according to Kim Sutton-Tyrrell, associate professor of epidemiology at Pitt's Graduate School of Public Health.

The report was presented at March's Conference on Cardiovascular Disease Epidemiology and Prevention.

"The important news for pre-menopausal women is that risk factors such as smoking and increased levels of bad, or low density, cholesterol, strongly predict whether they will develop heart disease after menopause," Sutton-Tyrrell said. "It's very likely that young, pre-menopausal women who modify these factors will decrease later development of heart disease."

The study, involving 219 women in their late 50s and early 60s, found that measurements of vascular disease in carotid arteries, or in the aorta, strongly correlated with the extent of disease in coronary arteries.

"We are excited about our findings for the management of post-menopausal women because we know that vascular disease generally appears in the aorta and the carotid artery before it appears in the heart," Sutton-Tyrrell added. "By detecting early vascular disease in the aorta or carotids, we may be able to predict who is at risk for coronary artery disease. By modifying risk factors in these women, we may be able to delay the development of heart disease or prevent it altogether in post-menopausal women. These steps could significantly decrease the incidence of heart attacks in this population."

EBCT is an ultra-fast computed tomography scanner that non-invasively can take 30 pictures of the heart in the time it takes to hold one deep breath. EBCT measures the extent of calcification inside blood vessels. Sonar-like ultrasound employs sound waves to measure the thickness of blood vessel walls and identify areas where plaque has deposited. Using both techniques, doctors can spot arterial plaque build-up long before life-threatening obstructions occur.

Sutton-Tyrrell's team also found that higher pre-menopausal blood pressure was a strong predictor of post-menopausal heart disease only in women taking hormone replacement therapy (HRT), which combines the hormones progesterone and estrogen. High blood pressure did not predict heart disease in women not on HRT.

"These findings may help explain why the large-scale Heart and Estrogen/Progesterone Replacement Study recently failed to find a benefit of HRT for women with pre-existing heart disease," Sutton-Tyrrell said. "We know that estrogen protects against heart disease, but it is possible that these benefits are off-set by adverse effects of progesterone on blood pressure."

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Photodynamic therapy found effective in treatment of swallowing problems

Photodynamic therapy (PDT) relieves swallowing problems from esophageal cancer in the majority of patients treated, according to a University of Pittsburgh Cancer Institute (UPCI) study.

The study involved patients who had primary esophageal cancer or who had recurrence after other treatments.

"Although further studies need to be done in this area, we found PDT to be effective in our patients," said James D. Luketich, senior co-author, Pitt assistant professor of surgery, co-director of UPCI's Lung Cancer Program, and section head, thoracic surgery. "This is one of the first reports after FDA approval of PDT that it is effective in relieving swallowing problems in patients with esophageal cancer."

The study was conducted at UPCI from November 1996 to June 1998. Physicians treated 77 patients with inoperable esophageal cancer using PDT.

During PDT, surgeons administer an injection of Photofrin, a light-sensitizing drug, which is absorbed by the body's tissues.

The drug remains inactive until later activated by a nonthermal red laser light at the end of a thin, optic fiber probe. The doctor feeds this line down the patient's esophagus and targets the cancer cells. Once in place, the laser light activates the drug, destroying the cancer cells and leaving surrounding healthy tissue largely unharmed.

Results were reported at last month's annual meeting of the Society of American Gastrointestinal Endoscopic Surgeons. The study's co-author is Ninh T. Nguyen, currently of the University of California at Davis, who previously worked at UPMC Health System.

Since introducing PDT to the Pittsburgh region in 1996, UPMC physicians have performed more than 550 treatments in patients with esophageal cancer and more than 60 patients with obstructive lung cancer, making UPCI the most active PDT center worldwide.

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New robotic device allows more precise brain surgery

Neurological surgeons at UPMC Presbyterian are using a new robotic guidance system that allows brain surgery to be performed with greater precision.

The device, called the SurgiScope, enables surgeons to better plan their approach to brain surgery, making smaller incisions possible and reducing risk to the patient.

The system consists of a spider-like, ceiling-hung robotic arm, a microscope and interactive guidance based on magnetic resonance (MR) or computed tomography (CT) images. Doctors use it both for planning surgery and to guide them during the operation.

"This system allows us to more accurately pinpoint and remove brain tumors," said L. Dade Lunsford, chief of neurological surgery at Pitt's School of Medicine, Lars Leksell Professor of Neurological Surgery, professor of radiation oncology and professor of radiology.