Tuesday, 28 May, 2024
HomeA FocusRobust study finds stents no better than drugs for many, challenging current...

Robust study finds stents no better than drugs for many, challenging current practice

Many patients with severe but stable heart disease who routinely undergo stenting would do as well by just taking medications and making lifestyle changes, writes MedicalBrief. The seven-year ISCHEMIA study, sponsored by the US National Heart, Lung and Blood Institute, could save millions in treatment costs, if current guidelines are changed.

Reuters Health says the $100m government-backed study, presented at the American Heart Association (AHA) meeting in Philadelphia, is the largest yet to look at whether procedures to restore normal blood flow in patients with stable heart disease offers an added benefit over more conservative treatment with aspirin, cholesterol-lowering drugs and other measures.

At least two prior studies determined that artery-clearing and stenting or bypass surgery in addition to medical treatment does not significantly lower the risk of heart attacks or death compared with non-invasive medical approaches alone.

Many cardiologists are reluctant to change practice in part because patients who get stents to keep the artery open report feeling better right away, experts said. NYU Langone cardiologist Dr Judith Hochman, who chaired the study, estimated that some 500,000 new patients a year are diagnosed with stable coronary artery disease, in which heart arteries narrowed by fatty deposits cause periodic angina, or chest pain, typically after exercising or emotional distress.

Current guidelines recommend patients with severe narrowing of their arteries have heart bypass surgery or a stent implanted to restore blood flow. Stents are tiny tubes that keep the artery open after blockage-clearing angioplasty. “There’s always been a fear that if you don’t do something quickly, they will have a heart attack or drop dead,” Hochman said.

The 7-year, 5,179-patient ISCHEMIA study did not show a significant benefit from that course of action. “For those with mild or no chest pain, there’s really not a role for immediately stenting,” Hochman said.

Just eliminating unnecessary stenting procedures could save the US healthcare system $570m annually, said Stanford University School of Medicine cardiologist and study co-chair Dr David Maron. He estimates the cost per stenting procedure at about $25,000 and bypass surgery at $45,000.

“I would hope this would change practice,” said Dr William Boden of the VA New England Healthcare System, another study author. “We are wasting a lot of money.”

“You would think that if you fix the blockage the patient will feel better or do better,” said Dr Alice Jacobs, director of Cath Lab and Interventional Cardiology at Boston University, in a New York Times report. The study, she added, “certainly will challenge our clinical thinking.”

“This is an extraordinarily important trial,” said Dr Glenn Levine, director of cardiac care at Baylor College of Medicine in Houston.  The results will be incorporated into treatment guidelines, added Levine, who sits on the guidelines committee of the American Heart Association.

The main goal of the trial was an overall reduction in deaths, heart attacks, hospitalisation for unstable chest pain or heart failure and resuscitation after cardiac arrest. On these measures, the addition of stenting or bypass surgery to reroute blood flow around the arterial blockage was no better at reducing the adverse events than medical therapy alone. The invasive treatments did result in better symptom relief and quality of life in those who had frequent chest pain.

The trial, sponsored by the National Heart, Lung and Blood Institute, involved patients with moderate to severe but stable ischemia – a condition in which clogged arteries are not able to supply the heart with enough oxygen-rich blood.

Everyone received medicines and lifestyle advice, while half also had one of the invasive procedures. Cleveland Clinic cardiologist Dr Steven Nissen was convinced. “We can reserve these interventions for people who truly fail medical therapy,” he said.

Experts said the study was well done, and its findings will be hard to ignore. But it may take several years for the changes to filter into practice, especially in community settings, said Dr Ashish Pershad, an interventional cardiologist at Banner – University Medicine Heart Institute in Phoenix.

The findings do not apply to all heart patients, including those with blockages in the left main coronary artery, Hochman said. And, she added, “if you’re having a heart attack, stents save lives.”

“This study clearly goes against what has been the common wisdom for the last 30, 40 years” and may lead to less testing and invasive treatment for such patients in the future, said Dr Glenn Levine, a Baylor College of Medicine cardiologist with no role in the research. Some doctors still may quibble with the study, but it was very well done “and I think the results are extremely believable,” he is quoted in a Stat News reports as saying.

Why might medicines have proved just as effective at reducing risks? By-passes and stents fix only a small area. Medicines affect all the arteries, including other spots that might be starting to clog, experts said. Drugs also have improved a lot in recent years.

Having a procedure did prove better at reducing chest pain, though. Of those who had pain daily or weekly when they entered the study, half in the stent-or-bypass group were free of it within a year versus 20% of those on medicines alone. A placebo effect may have swayed these results – people who know they had a procedure tend to credit it with any improvement they perceive in symptoms.

Dr Alice Jacobs, a Boston University cardiologist who led a treatment-guidelines panel a few years ago, said any placebo effect fades with time, and people with a lot of chest pain that’s unrelieved by medicines still may want a procedure.

“It’s intuitive that if you take the blockage away you’re going to do better, you’re going to feel better,” but the decision is up to the patient and doctor, she said.

The report said the bottom line: There’s no harm in trying medicines first, especially for people with no or little chest pain, doctors said.

Background: Myocardial infarction (MI) complicated by cardiogenic shock (CS) is associated with high mortality. Early coronary revascularization improves survival, but the optimal mode of revascularization remains uncertain. We sought to characterize practice patterns and outcomes of coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) in patients with MI complicated by CS.
Methods: Patients hospitalized for MI with CS between 1/2002 and 12/2014 were identified from the United States National Inpatient Sample. Trends in management were evaluated over time. Propensity score matching was performed to identify cohorts with similar baseline characteristics and MI presentations who underwent PCI and CABG. The primary outcome was in-hospital all-cause mortality.

Results: A total of 386,811 hospitalizations for MI with CS were identified (67% STEMI). Overall, 62.4% of patients underwent revascularization, with PCI in 44.9%, CABG in 14.1%, and a hybrid approach in 3.4%. Coronary revascularization for MI and CS increased over time, from 51.5% in 2002 to 67.4% in 2014 (p-for-trend<0.001), driven by increases in PCI (Figure). Patients who underwent CABG were more likely to have diabetes mellitus (35.5% vs. 29.2%, p<0.001) and less likely to present with STEMI (48.7% vs. 80.9%, p<0.001) or cardiac arrest (11.0% vs. 21.8%, p<0.001) than those who underwent PCI. CABG (without PCI) was associated with lower mortality than PCI (without CABG) overall (18.9% vs. 29.0%, p<0.001; adjusted OR 0.58 [0.55-0.61]) and in a propensity-matched subgroup of 20,058 patients (18.9% vs. 26.3%, p<0.001).
Conclusions: CABG was associated with lower in-hospital mortality than PCI among patients with MI complicated by CS. Due to the likelihood of residual confounding, a randomized trial of PCI versus CABG in patients with MI, CS, and multi-vessel coronary disease is warranted to determine the optimal revascularization strategy in this high-risk population.

Nathaniel R Smilowitz, Carlos L Alviar, Stuart D Katz, Judith S Hochman

[link url="https://in.reuters.com/article/health-heart-stent/stents-no-better-than-drugs-for-many-heart-patients-us-study-idINKBN1XR01P"]Reuters Health report[/link]

[link url="https://www.nytimes.com/2019/11/16/health/heart-disease-stents-bypass.html?"]New York Times report (registration required)[/link]

[link url="https://www.statnews.com/2019/11/16/big-study-casts-doubt-on-need-for-many-heart-procedures/"]Stat News report[/link]

[link url="https://www.ahajournals.org/doi/10.1161/circ.140.suppl_1.16598"]AHA Scientiic Sessions abstract[/link]

MedicalBrief — our free weekly e-newsletter

We'd appreciate as much information as possible, however only an email address is required.