Cardiovascular Services

Specializing Institutions

Cardiovascular medicine focuses on the treatment of acquired diseases affecting the heart and the great vessels. Conditions affecting the heart include coronary artery disease, arrhythmia, heart failure and stroke. Cardiovascular diseases claim approximately 17.1 million lives each year. Tobacco use, an unhealthy diet, and physical inactivity increase the risk of heart attacks and strokes. Cardiovascular risks are particularly higher for women after menopause. Prevention programs in which physicians, physical therapists, nurses and exercise consultants work together often help patients take control of their health. The healthcare industry has been making strides in the past two decades researching and creating innovative and comprehensive treatment, prevention and detection options for patients with complex diseases of the heart, blood vessels, and circulatory system.

Cardiovascular surgery is surgery performed on the heart, the aorta and other vessels. Procedures range from Open Heart Surgery to minimally invasive procedures performed with the da Vinci® Surgical System, an advanced technology that enables surgeons to perform delicate operations with the least intrusion to the patient and is available at the South Texas Medical Center.

Non-invasive cardiac monitoring includes Holter Monitoring, also known as Ambulatory EKG or Ambulatory ECG. The Holter Monitor is portable and allows for continuous heart monitoring without interrupting the patient’s daily activities. Invasive cardiac monitoring includes Cardiac Electrophysiology, a study that requires catheterization to record spontaneous cardiac activity and cardiac responses to programmed electrical stimulation. Cardiac catheterization is common and can be used to perform a number of procedures including angioplasty, PCI, angiography, balloon septostomy and Electrophysiology studies. Both non-invasive and invasive cardiac procedures are performed at the South Texas Medical Center.

Cardiac Implantations, such as Permanent Pacemaker Implantations, or pacemakers, are used to regulate cardiac rhythm through electrical impulses. These implantations help maintain an adequate heart rate for patients struggling with low heart rate or a block in their heart’s electrical conduction. Patients can get treated for irregular heart rate and get cardiac implantations at several institutions at the South Texas Medical Center.

Another device used to detect irregular cardiac activity, and also offered at the South Texas Medical Center, is the Implantable Cardioverter Defibrillator or ICD. This implantable battery-powered electrical impulse generator helps patients who are at risk of sudden cardiac death resulting from ventricular fibrillation and ventricular tachycardia.

Cardiovascular Articles

  • Clockwork heart pacemaker does away with batteries

    By Ben Hirschler

    BARCELONA (Reuters) - Swiss engineers, famous for making the world's finest watches, are turning their hands to cardiology with a prototype battery-less pacemaker based on a self-winding wristwatch.

    Current pacemakers, which help the heart beat more regularly, offer a lifeline for many patients with cardiac problems but the need for battery power is a limiting factor, since replacing them requires a surgical intervention.

    Adrian Zurbuchen of the University of Bern's cardiovascular engineering group aims to get around the problem with his device, using automatic clockwork first developed for pocket watches by Swiss watchmaker Abraham-Louis Perrelet in 1777.

    In the same way that an automatic watch winds itself when it moves on the wrist, the clockwork pacemaker generates electrical current using the movement of heart muscle. To do this, it is stitched directly on to the pulsating heart.

    So far the experimental system has only been tested on pigs, Zurbuchen told the annual meeting of the European Society of Cardiology in Barcelona on Sunday. The animals hearts were successfully regulated to a steady 130 beats per minute.

    "This is a feasibility study. We have shown that it is possible to pace the heart using the power of its own motion," Zurbuchen said.

    The research is still at an early stage and there is, as yet, no schedule for human testing. Zurbuchen has also not discussed the idea with potential industrial partners but he said it was "probably a good time to look" for backers.

    Other researchers are investigating ways to get rid of batteries in pacemakers by transmitting power through the body from an external source - but the idea of using clockwork is novel.

    Automatic watches work because they have an eccentric weight that pivots when the wearer's arm moves. This rotation progressively winds a spring that then turns the watch mechanism. In the new Swiss pacemaker, the mechanical spring unwinds to spin an electrical micro-generator.

  • Low-carb diets may beat low-fat options for weight loss, heart health

    By Andrew M. Seaman

    A low-carbohydrate diet is better for losing weight and may also be better for lowering the risk of heart disease than a low-fat diet, according to a new study.

    While low-carb diets have outperformed other diets when it comes to weight loss, some researchers feared they might be worse for heart health because they tend to be high in fat.

    The new study shows that with proper nutritional counseling, people can lose more weight and lower their risk factors for heart disease on a low-carbohydrate diet, said the lead author, Dr. Lydia Bazzano of Tulane University in New Orleans.

    "This study shows if you are overweight and have cardiovascular disease risk factors and haven't had success on other diets, certainly a low-carbohydrate diet is worth a try," said Bazzano.

    Carbohydrates are found in food and include sugar, fiber and starches that give the body energy. Some carbs - like those in whole grains and fruits - are healthier than others - like those in white bread and other processed foods.

    Bazzano and her colleagues write in Annals of Internal Medicine that low-carb diets have become popular weight loss strategies in recent years. Studies on their effects on cardiovascular risk factors have produced mixed results, however.

    For the new study, she and her colleagues recruited 148 obese men and women between the ages of 22 and 75. None of the participants had heart disease or diabetes.

    Half were randomly assigned to follow a low-carbohydrate diet for a year, and the other half were assigned to a low-fat diet for a year. They were told to not change their physical activity throughout the trial.

    All participants attended regular meetings where they learned about portion control, healthy eating and overall nutrition. They were also offered one meal-replacement bar or shake per day.

    The only difference between the groups was the proportions of carbohydrate and fat in their diets.

    Those in the low-carbohydrate group were told to eat at no more than 40 grams of digestible carbohydrates per day. ("Digestible carbs" equals total carbs minus total fiber.)

    Those in the low-fat group were told not to get more than 30 percent of their daily energy from fat and no more than 55 percent of their daily energy from carbohydrates.

    Overall, about four of every five participants were still following the diets 12 months later.

    During that time, the researchers found, people on the low-carbohydrate diet lost more weight and more body fat than those on the low-fat diet.

    The difference in lost weight between the two groups would represent about eight additional pounds.

    Additionally, the researchers saw no increases in total cholesterol or "bad" LDL cholesterol between the two groups. Bazzano said that's good news since some thought a low-carbohydrate diet would increase cholesterol levels.

    Those in the low-carbohydrate group had lower levels of fat circulating in their blood and had lower scores on a measure often used to predict the risk of a heart attack or stroke within the next 10 years.

    "I thought that was a very striking finding," Bazzano said. She added that the score that predicts risk of future heart attacks and strokes was computed after the study was finished and is less reliable than the other risk factors they measured.

    Dr. David Jenkins, who wasn't involved in the study, told Reuters Health, "This doesn't look to me to say 'eat all the meats you want to lower your carbohydrates.' That's just one way to do it."

    Instead, Jenkins said, people in this study appeared to improve their overall diets. For example, they were eating foods with healthier fats, such as nuts and beans.

    He also said they seemed to eat more fiber and cut down on processed foods with more carbohydrates.

    "I think it's another testament to what one can do with a more plant-based diet using the right macronutrient profile," said Jenkins of the Department of Nutritional Sciences at the University of Toronto and the Keenan Research Centre at St. Michael's Hospital.

    Bazzano agreed that the overall diets improved among the participants and they were encouraged to eat healthier forms of protein like chicken, fish, nuts and beans.

    She also said her team is not sure why people on the low-carbohydrate diets lost more weight and had lower risk factors for heart disease after one year. It's not clear, she added,if there would still be a difference after a longer period.

    SOURCE: Annals of Internal Medicine, online September 1, 2014.

  • U.S. startups get OK for smartphone-based heart tracking

    By Christina Farr

    SAN FRANCISCO (Reuters) - For a growing U.S. aging population, tracking heart health via a smartphone can mean the difference between life and death.

    This week, two Silicon Valley startups received a green-light from the U.S. Food and Drug Administration for mobile applications that monitor patients from home, a step forward for a nascent digital health industry that has pressed for more clarity from the agency on regulations.

    AliveCor said it received the FDA's approval to detect serious heart conditions in electrocardiogram (ECG) readings taken from a mobile device. The company says its newly-approved algorithm can detect atrial fibrillation, a form of cardiac arrhythmia that affects about one in four adults over the age of 40. If its smartphone-compatible heart-monitor device detects an abnormality, a physician could intervene before the patient experiences a stroke or other life-threatening event.

    The device fits most smartphones and rests on a patient's finger or chest to record an ECG.

    "Atrial fibrillation is very hard to identify," said Euan Thomson, AliveCor's chief executive. "A large group of people have it, but don't know they have it."

    Thomson said AliveCor can detect the condition and send the data to a cardiologist for review. The company plans to incorporate this algorithm into its application and make it available to consumers by September.

    In addition, startup Vital Connect received approval for a patch -- the "HealthPatch MD" -- that patients can attach to one of three areas on their chest and view their own biometric data on a mobile device.

    Sensors embedded in the band-aid sized patch track heart rate, pulse variability, respiratory rate, skin temperature, steps, "fall" detection and more.

    Valeska Schroeder, the company's vice president of product management, said the medical device will hit the market in the United States, and potentially also Canada and Europe, by the end of the year. Patients need a prescription to buy the device.

    What is unique about Vital Connect is that it puts the data in context, Schroeder explained. If a patient's heart rate spikes when they are lying flat in bed, that is typically a worrisome sign. But during exercise or a fall, it is a typical occurrence. If they opt in, physicians get notified when their patients hit or exceed set thresholds.

    Vital Connect first hit the headlines when Apple poached one of its senior executives, Ravi Narasimhan, as part of a larger effort to hire talent from the medical field.

    "We know we are working in a hot market," said Schroeder. "We know other firms are interested in making related products."

    These companies are taking different approaches, but they share the goal of helping doctors track patients remotely and take steps to prevent fatal outcomes. Data may also inform physicians about whether their patients should schedule an in-person or emergency room visit.

    According to the Centers for Disease Control, 129.8 million people visited the emergency room in 2010 and 13 percent of these visits resulted in hospital readmission.

    "By getting an intelligent device in the hands of a patient, we hope to fulfill the vision for mobile health," said Thomson.

  • With high blood pressure, light to moderate drinking may protect heart

    By Kathryn Doyle

    NEW YORK (Reuters Health) - Drinking alcohol has been tied in the past to a higher risk of high blood pressure, but in a new analysis of past studies, researchers found that a drink or two a day seemed to protect even those with hypertension from heart disease and death.

    People with high blood pressure who have never been drinkers shouldn't start now based on the evidence from studies like these, said senior author Qi-Qiang He of the School of Public Health/Global Health Institute at Wuhan University in China.

    Observational studies only include data on what people do in their lives and what happens to them, and can't say for sure that one action, like drinking alcohol, causes a particular result.

    The new meta-analysis combines the data from nine previous studies involving a total of nearly 400,000 people with high blood pressure. In all of the studies, alcohol consumption, including wine, beer and spirits, was recorded, as were cases of heart disease, stroke, heart failure and death from any cause.

    The researchers divided the participants into four groups: occasional or never drinkers, those who drank about 10 grams (about a third of an ounce) of ethanol - pure alcohol - per day, and those who drank 20 or 30 grams of ethanol per day.

    In the U.S., a five-ounce glass of wine, a 12-ounce bottle of beer and a 1.5-ounce shot of liquor each contain about 14 grams of alcohol.

    Overall, He's team found that cardiovascular disease, heart attacks, strokes and other risks went down as alcohol consumption went up, according to the results published in Mayo Clinic Proceedings.

    This study included relatively few heavy drinkers, and other studies have found that the heart risk decline disappears for very heavy drinkers or binge drinkers, the authors caution.

    For all causes of death, the risk was lowest among those who drank between eight and 10 grams of alcohol per day, and the risk was higher for those who drank more or did not drink at all. Light to moderate drinkers were about 18 percent less likely to die over the course of a study than people who did not drink.

    "This was firstly found true in people with normal blood pressure," He told Reuters Health by email.

    In the general population, some studies suggest that alcohol consumption might enhance heart rate variability or keep plaque from building up inside arteries, but the mechanism is still not clear, He said.

    If anything, beneficial effects of alcohol should be even more pronounced for people without high blood pressure, said Dr. Franz H. Messerli a cardiology expert at the Icahn School of Medicine at Mount Sinai in New York.

    "One to 2 drinks daily is said to be the goldilocks amount of alcohol," Messerli told Reuters Health by email.

    But even these small amounts of alcohol have been associated with an increased risk for high blood pressure, he said.

    "We don't know whether moderate drinking is truly cardioprotective or if it is merely a marker of a healthy lifestyle," Messerli said.

    Moderate alcohol drinkers also tend to be part of the healthiest subset of the social landscape, he said.

    "Non-drinkers are usually older, eat a less healthy diet and exercise less than moderate drinkers," he noted.

    Messerli agreed that the study results should not be taken as encouragement for non-drinkers to take up drinking.

    Suggesting that people start having a few drinks here and there to reduce their risk of various heart problems may actually lead to binge drinking which increases the risk of stroke, Messerli said.

    SOURCE: Mayo Clinic Proceedings, online August 1, 2014.

  • Amgen seeks U.S. approval of new cholesterol-fighting drug

    By Reuters Staff

    (Reuters) - Amgen Inc said on Thursday it applied to U.S. health regulators to sell its cholesterol fighter, evolocumab, becoming the first company to seek approval of a medicine from a closely watched new class of potent heart drugs.

    Amgen is racing with Regeneron Inc to bring to market the potentially lucrative new drugs aimed at patients unable to tolerate widely used statins, and those who cannot sufficiently lower cholesterol despite use of statins, such as Pfizer Inc's Lipitor, or other medicines.

    The injectable drugs work by blocking a naturally occurring protein called PCSK9 that prevents the liver from removing LDL cholesterol, the "bad" cholesterol, from the bloodstream.

    In large clinical trials, evolocumab cut LDL levels by more than 50 percent even in patients already taking other cholesterol medicines.

    Analysts have forecast multibillion-dollar sales for the new biotech drugs, if they demonstrate an ability to significantly reduce heart attacks and deaths in larger ongoing trials, as statins have.

    While Amgen was the first to file for U.S. approval of a PCSK9 inhibitor, Regeneron and French partner Sanofi have an ace up their sleeve that could enable them to catch up or even reach the market first with their drug, alirocumab.

    In late July, the companies said they paid $67.5 million to acquire a special voucher from BioMarin Pharmaceutical Inc that could assure alirocumab an expedited six-month U.S. regulatory review, rather than the standard 10 months.

    Pfizer Inc is also developing a PCSK9 inhibitor, but is behind Amgen and Regeneron.

    Amgen is expected to submit approval applications for evolocumab to regulators in Europe and other markets in the coming months.