February 19, 2009 - When it comes to a heart attack, every second counts, and the Occluded Artery Trial (OAT) underscores how very important it is for individuals experiencing a heart attack to take their symptoms seriously, call 911, and undergo prompt treatment, says the Society for Cardiovascular Angiography and Interventions (SCAI).
SCAI said the OAT study examined a minority of heart attack patients who received very delayed treatment for heart attack (12 or more hours following heart attack onset). Less than one-third of heart attack patients fall into this specific category of patients. The patients studied in OAT did not experience the full benefit of angioplasty and stenting, because they received treatment after the heart was irreversibly damaged and no longer able to significantly benefit from the oxygenated blood flow that angioplasty provides. This is a dangerous situation that can lead to heart failure.
The OAT study found 83 percent of the patients entered into the trial did not have angina and 91 percent had minimal or no myocardial ischemia on nuclear testing. In this young patient group (average age 58 years), only one vessel was blocked in 82 percent of the patients and heart pumping function was nearly normal in the majority of patients.
“This study communicates a valuable message to our patients – one we cannot overemphasize: If you think you are having a heart attack, don’t delay,” said Dr. Mark Turco, SCAI trustee and director of the Center for Cardiac and Vascular Research at Washington Adventist Hospital, Takoma Park, MD. “We know within 90 minutes of experiencing a heart attack, angioplasty and stenting are unquestionably the standard of care. This procedure stops life-threatening heart attacks in their tracks and prevents debilitating damage to the heart muscle. The essential point to take away from this study is to recognize the warning signs of a heart attack, to take these signs seriously and seek medical attention immediately.”
The study found in such very stable patients without angina and with one-vessel blockage, medical therapy is an excellent option.
SCAI said the take-away message from OAT is that more education is needed with the general public. If someone experiences symptoms that could be a heart attack, they should take action immediatel and call 911 and get to a hospital as quickly as possible. It is important to know and understand the signs of a heart attack, including chest discomfort, shortness of breath, discomfort in the upper body (arms, back, neck, jaw, stomach), breaking out in a cold sweat, or feeling nauseous or lightheaded. Resist the temptation to interpret symptoms as indigestion, upset stomach, exhaustion, or being out of shape.
Because heart attack symptoms are often more subtle in women, their treatment is more often delayed, making this message particularly pertinent for them. For both women and men, getting to the hospital quickly and undergoing angioplasty and stenting to open blocked arteries can mean the difference between life and death, SCAI said.
SCAI emphasizes that the findings of this study should not be interpreted as applying to all patients experiencing a heart attack, which could inadvertently lead them to delay their care. Angioplasty is the clinically proven gold standard of care for patients experiencing a heart attack. The patients studied in OAT did not experience the full benefit of angioplasty and stenting because they received treatment after the heart was irreversibly damaged and no longer able to significantly benefit from the oxygenated blood flow that angioplasty provides. This is a dangerous situation that can lead to heart failure.
SCAI emphasizes that it is important to evaluate studies carefully to be sure which patients they apply to. OAT applies to the most stable patients -- those with no or minimal angina, one-vessel disease, and normal heart pumping function at an average of eight days after a heart attack, without evidence of heart muscle that was lacking oxygen. Other trials such as BRAVE 2 (JAMA. 2005;293(23):2865-2872) evaluated older patients who underwent PCI at an average of 22 hours after presentation. This randomized trial demonstrated significant mortality benefits, not just quality-of-life outcomes, if the patient underwent PCI. This suggests that the timing of intervention may be very important with respect to outcome. These questions require careful prospective construction if they are to be applied to outcomes measures for clinical applications. As always, the clinical situation of each individual patient must be carefully considered to develop the best care plan based on all of the evidence, SCAI said.
“We have made tremendous advances in treating and preventing heart attacks. Millions of patients are alive today because of angioplasty and stenting. But there is always more to do, which is why SCAI is an active partner in the Door-To-Balloon Alliance, which seeks to save time and ultimately save lives by improving the time a heart attack patient arrives in the cath lab and receives life-saving treatment from an interventional cardiologist,“ said Dr. Steven R. Bailey, SCAI president-elect and chief of the division of cardiology at the University of Texas Health Sciences Center at San Antonio.
For more information: www.scai.org