Results of one of the largest and most important studies in a decade, the International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA), were just announced.
The study was conducted to settle theories that have been debated by cardiologists for decades. The procedures in question were surgery and stents versus lifestyle changes and medication to reduce the risk of a heart attack for people with ischemic heart disease (blood flow restriction).
And the Answer is . . .
The studies, funded by the National Institute of Health, reveal that lifestyle changes and medication are just as effective as invasive procedures (bi-pass surgery and stents) for the reduction of cardiac events.
However, two studies showed that surgery and stents offer improved relief of symptoms and a better quality of life for patients with periodic chest pain.
About Coronary Artery Disease
The most common heart disease is coronary artery disease. It is caused when arteries constrict and limit the amount of blood that flows to the heart.
As the leading cause of fatalities in the U.S, it affects approximately eighteen million Americans. Not everyone experiences symptoms or are aware that they have heart disease. In those cases, the first symptom will unfortunately be either a heart attack or cardiac arrest.
About the Studies
A total of 8518 people enrolled between 2012 and 2018. In order to produce the most accurate results, patients with extremely abnormal stress tests were included in the trial.
Therefore, study participants were chosen on the basis of testing for coronary blood flow restriction. Researchers monitored patients for three years. The average age was 64. Studies were conducted in thirty-seven countries at 320 sites.
Twenty one percent of patients had weekly or daily chest pain, and thirty-five percent of participants had not experienced chest pain within a month prior to their enrollment. The majority of patients had at some point experienced chest pains.
Two treatment strategies were compared. The invasive treatment consisted of counseling and medication plus coronary procedures if a patient’s stress test indicated a problem.
Invasive procedures were compared against conservative treatment, which uses medications for controlling blood pressure, angina, and cholesterol. Exercise and diet counseling were included.
Invasive or Conservative
Researchers studied the two strategies in connection with heart failure, cardiovascular death, resuscitated cardiac arrest, and angina, which is chest pain caused by reduced blood flow to the heart. In addition, quality of life was observed.
Over a five-year period, twenty-one percent of the patients in the conservative treatment group had undergone stent implantation or received bypass surgery. The rest of the group remained on their medication.
Of the participants in the intervention group, seventy-nine percent received stents or bypass surgery.
Between the two groups, the death rate was similar (145 vs. 144).
Dr. Judith Hochman, co-lead author, acknowledged that surgical procedures carry a risk of heart damage. However, she noted that this type of heart damage is not as serious as a sudden heart attack that is not related to a surgical procedure.
There was definite consensus throughout the study that if patients had chest pain or angina, the invasive procedures showed a greater benefit to the patient than the conservative methods.
A Four Year Follow-up
Patients were advised to consult with their physicians when determining which strategy to follow. The study participants were followed for four years after leaving the trial. The researchers reported an improvement in the patients’ symptoms and quality of life after being treated with the invasive strategy.
The improvement occurred in about two-thirds of patients with angina. However, no benefit was observed for patients who did not exhibit symptoms.
Dr. David Maron of Stanford University stated that people with angina may feel safe being treated with medication and following a lifestyle change, but invasive therapy should be considered in the event of continuous symptoms.
In conclusion, there is still a need for additional long-term monitoring as a way to determine an accurate prognosis for the conservative and the invasive treatments.