{"product_id":"choosing-the-right-blockages-to-fix-after-a-heart-attack-the-air-stemi-trial","title":"Choosing the Right Blockages to Fix After a Heart Attack: The AIR-STEMI Trial","description":"\u003cp\u003eComplete coronary-artery revascularization is recommended for patients with ST-segment elevation myocardial infarction (STEMI, a major heart attack caused by a fully blocked heart artery) and multivessel coronary artery disease (blockages in more than one heart artery). However, it was unclear which of the additional, \"nonculprit\" blockages actually needed to be opened. In a large international trial called AIR‑STEMI, researchers found that using a new imaging-based method—\u003cstrong\u003efunctional coronary angiography\u003c\/strong\u003e, which estimates the physiological significance of a blockage directly from angiogram images without the need for pressure wires—to choose which nonculprit lesions to treat significantly reduced the risk of major heart-related events compared with using conventional (visual) angiography alone. Understandable, comprehensive summary of the findings is below.\u003c\/p\u003e\n\u003ch1\u003eChoosing the Right Blockages to Fix After a Heart Attack: The AIR-STEMI Trial\u003c\/h1\u003e\n\u003ch2\u003eTable of Contents\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"#ddn-key-points\"\u003eKey Points\u003c\/a\u003e\u003c\/li\u003e\n\n\u003cli\u003e\u003ca href=\"#background\"\u003eWhy this research matters\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"#methods\"\u003eHow the study was designed\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"#eligibility\"\u003eWho could join the study\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"#randomization\"\u003eHow patients were assigned to a treatment strategy\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"#treatments\"\u003eThe two treatment strategies compared\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"#outcomes\"\u003eOutcomes the researchers measured\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"#stats\"\u003eHow the data were analyzed\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"#patient-results\"\u003ePatient characteristics and enrollment results\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"#procedural-results\"\u003eProcedural details: what actually happened during treatment\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"#primary-result\"\u003ePrimary finding: fewer major events with physiology-guided treatment\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"#secondary-results\"\u003eSecondary results: heart attacks, strokes, and repeat procedures\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"#safety-results\"\u003eSafety results: kidney injury and major bleeding\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"#implications\"\u003eWhat this means for patients\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"#limitations\"\u003eLimitations of the study\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"#recommendations\"\u003ePractical recommendations\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"#ddn-faq\"\u003eFrequently Asked Questions\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"#source\"\u003eSource Information\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003c!-- ddn:keypoints:start --\u003e\n\u003ch2 id=\"ddn-key-points\"\u003eKey Points\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eIn the AIR-STEMI trial of 1,823 patients, functional coronary angiography guided which nonculprit blockages to stent after STEMI.\u003c\/li\u003e\n\u003cli\u003eTreating only blockages with an estimated FFR of 0.80 or less reduced major heart events compared with visually guided stenting of all narrow arteries.\u003c\/li\u003e\n\u003cli\u003eThe physiology-guided strategy cut heart attacks by about half and lowered repeat procedures, kidney injury, and total contrast dye use.\u003c\/li\u003e\n\u003cli\u003eAbout 38 percent of patients in the physiology-guided group received no extra nonculprit stent, yet their outcomes were still better overall.\u003c\/li\u003e\n\u003cli\u003ePatients should ask whether functional coronary angiography will be used to decide if additional blockages actually need stents after a heart attack.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- ddn:keypoints:end --\u003e\n\n\u003ch2 id=\"background\"\u003eWhy this research matters\u003c\/h2\u003e\n\u003cp\u003eWhen a patient arrives at the hospital with a STEMI, doctors usually open the completely blocked \"culprit\" artery as quickly as possible. But roughly one in two STEMI patients also has \u003cstrong\u003emultivessel coronary artery disease\u003c\/strong\u003e—meaning other heart arteries are narrowed by plaque. Treating those additional arteries during the same hospital stay is called \u003cstrong\u003ecomplete coronary-artery revascularization\u003c\/strong\u003e, and it is now considered the standard of care.\u003c\/p\u003e\n\u003cp\u003eThe problem: visual inspection of other blockages and their severity—simply looking at the angiogram (an X-ray movie of the arteries filled with dye)—is not always enough. Appearance does not show whether the narrowed artery meaningfully limits blood flow. The conventional, visual approach risks overtreating harmless blockages, which exposes patients to extra procedures, extra contrast (dye) that can harm the kidneys, and added risk of bleeding.\u003c\/p\u003e\n\u003cp\u003eAn alternative to visual inspection is a technique called \u003cstrong\u003efunctional coronary angiography\u003c\/strong\u003e. This computer-based method estimates the \u003cstrong\u003efractional flow reserve (FFR)\u003c\/strong\u003e—a measurement of whether a narrowing truly reduces blood flow to the heart muscle—directly from the angiographic images themselves. It does not require threading a pressure wire into the artery or giving drugs that stress the heart. It also provides a \"pullback\" analysis that helps doctors plan exactly where stents should be placed.\u003c\/p\u003e\n\u003cp\u003eThe AIR-STEMI investigators wanted to know if this physiology-guided approach—treating only blockages that are functionally significant—beats the traditional visual approach. This is the first large randomized trial to test that question specifically in STEMI patients with multivessel disease.\u003c\/p\u003e\n\u003ch2 id=\"methods\"\u003eHow the study was designed\u003c\/h2\u003e\n\u003cp\u003eThis was an investigator-initiated, international, prospective, randomized superiority trial. That means it was not funded by a company seeking to sell a device, centers in more than one country participated, patients were followed forward in time, and patients were assigned randomly to one of two groups.\u003c\/p\u003e\n\u003cp\u003ePatients enrolled between \u003cstrong\u003eMay 8, 2023, and January 31, 2025\u003c\/strong\u003e, at \u003cstrong\u003e21 hospitals in Italy and Pakistan\u003c\/strong\u003e. Overall, 6,131 patients were screened for eligibility, and 1,823 entered the trial.\u003c\/p\u003e\n\u003cp\u003eThe Italian Health Ministry (administered through the University Hospital of Ferrara) was the primary sponsor. A nonprofit organization, Consorzio Futuro in Ricerca, coordinated the international centers and committees, with unrestricted funding from Sahajanand Medical Technologies and Siemens Healthineers, plus software licenses from Pulse Medical Imaging Technology and Pie Medical Imaging. Importantly, the sponsors had no role in the study design, data collection, analysis, or manuscript preparation. An independent data and safety monitoring committee oversaw the trial, and an independent clinical-events committee—whose members did not know which group each patient was in—adjudicated all reported clinical events.\u003c\/p\u003e\n\u003ch2 id=\"eligibility\"\u003eWho could join the study\u003c\/h2\u003e\n\u003cp\u003eYou were eligible if you were hospitalized with a STEMI, had already undergone successful \u003cstrong\u003epercutaneous coronary intervention (PCI)\u003c\/strong\u003e (a balloon-and-stent procedure) on the culprit lesion, and you also had multivessel disease—that is, at least one additional nonculprit artery narrowed by \u003cstrong\u003e50 to 99% of its normal width\u003c\/strong\u003e, with a minimum reference vessel diameter of \u003cstrong\u003e2.5 mm\u003c\/strong\u003e.\u003c\/p\u003e\n\u003cp\u003eKey reasons you could not participate included:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eDoctors could not clearly identify the culprit lesion.\u003c\/li\u003e\n\u003cli\u003eYour nonculprit blockage was in the \u003cstrong\u003eleft main coronary artery\u003c\/strong\u003e, the major artery that supplies most of the heart's left side.\u003c\/li\u003e\n\u003cli\u003eYou had planned or previous surgical bypass (CABG, coronary artery bypass grafting).\u003c\/li\u003e\n\u003cli\u003eYour life expectancy was less than 1 year.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eAll patients gave written informed consent before joining the trial.\u003c\/p\u003e\n\u003ch2 id=\"randomization\"\u003eHow patients were assigned to a treatment strategy\u003c\/h2\u003e\n\u003cp\u003eWithin 48 hours after successful treatment of the culprit lesion, eligible patients were randomly assigned in a 1:1 ratio to either the physiology-guided group or the conventional angiography-guided group. Randomization was done centrally through a secure web-based system, using a computer-generated allocation sequence. This means neither the patient nor the doctor could choose the group, and treatment assignments were hidden until the moment of randomization.\u003c\/p\u003e\n\u003cp\u003eTo keep the groups balanced, randomization was stratified according to:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003ethe treating center,\u003c\/li\u003e\n\u003cli\u003esex,\u003c\/li\u003e\n\u003cli\u003eage (younger than 75 years versus 75 years or older), and\u003c\/li\u003e\n\u003cli\u003ewhether the nonculprit vessel was the \u003cstrong\u003eleft anterior descending (LAD) artery\u003c\/strong\u003e or a different artery.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eAfter randomization, this was not a blinded trial: doctors and patients knew which strategy was being used. However, the committee that later judged which events counted as outcomes did not know the group assignments.\u003c\/p\u003e\n\u003ch2 id=\"treatments\"\u003eThe two treatment strategies compared\u003c\/h2\u003e\n\u003cp\u003ePatients in the \u003cstrong\u003ephysiology-guided group\u003c\/strong\u003e underwent functional coronary angiography for every nonculprit lesion with an estimated diameter stenosis of at least 50%. The computer estimated the FFR value; if the result was \u003cstrong\u003e0.80 or less\u003c\/strong\u003e, the lesion was labeled functionally important and treated with PCI, following a \"virtual-PCI\" plan based on the FFR pullback curve. If the functional assessment was negative (FFR value above 0.80), performing PCI on that lesion was considered a protocol violation. Analyses were performed at a central core laboratory using two validated angiography-derived FFR software systems: the Murray law–based quantitative flow ratio (AngioPlus Core) and the vessel FFR system (CAAS vFFR).\u003c\/p\u003e\n\u003cp\u003ePatients in the \u003cstrong\u003eangiography-guided group\u003c\/strong\u003e simply underwent PCI on every nonculprit lesion with an estimated stenosis of at least 50%—purely based on how the blockage looked on the angiogram, which is the traditional and still common real-world approach.\u003c\/p\u003e\n\u003cp\u003eIn both groups, doctors aimed to complete all revascularization during the initial hospital stay, either during the first procedure or in a staged procedure on a later day. At the treating team's discretion, complete revascularization was performed either in the initial index procedure or a separate staged procedure.\u003c\/p\u003e\n\u003cp\u003eAll patients received second-generation drug-eluting stents (stents coated with medication to prevent re-narrowing). There was a specific recommendation for sirolimus-eluting, biodegradable-polymer, ultrathin-strut stents (Supraflex Cruz). All patients received guideline-directed medical therapy for heart disease, and dual antiplatelet therapy (usually aspirin plus a second blood thinner such as ticagrelor or clopidogrel) was recommended for at least 12 months unless the bleeding risk was too high.\u003c\/p\u003e\n\u003ch2 id=\"outcomes\"\u003eOutcomes the researchers measured\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003ePrimary outcome (efficacy):\u003c\/strong\u003e a composite of the first occurrence of any one of these events, analyzed as \"time to first event\":\u003c\/p\u003e\n\u003col\u003e\n\u003cli\u003edeath from any cause,\u003c\/li\u003e\n\u003cli\u003emyocardial infarction (heart attack),\u003c\/li\u003e\n\u003cli\u003ecerebrovascular accident (stroke or transient ischemic attack—a \"mini-stroke\"), or\u003c\/li\u003e\n\u003cli\u003eischemia-driven revascularization, meaning a repeat stent or bypass procedure needed because of renewed blockage symptoms.\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003cp\u003e\u003cstrong\u003eKey secondary outcomes:\u003c\/strong\u003e the combined rate of cardiovascular death or heart attack; individual components of the primary outcome; ischemic stroke; and stent thrombosis (a blood clot forming inside the newly placed stent).\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003ePrimary safety outcome:\u003c\/strong\u003e a composite of contrast-associated acute kidney injury (kidney damage from the X-ray dye used during the procedure) or major bleeding, defined as \u003cstrong\u003eBleeding Academic Research Consortium (BARC) type 3, 4, or 5\u003c\/strong\u003e bleeding—which means bleeding requiring transfusion or surgery, or fatal bleeding.\u003c\/p\u003e\n\u003ch2 id=\"stats\"\u003eHow the data were analyzed\u003c\/h2\u003e\n\u003cp\u003eThe researchers powered the study to detect a 35% relative risk reduction with the physiology-guided strategy. They calculated that 1,718 patients would provide 80% statistical power at a two-sided alpha level of 0.05. To compensate for an expected 5% dropout rate, they aimed for at least 1,800 patients—and they enrolled 1,823.\u003c\/p\u003e\n\u003cp\u003eAll analyses followed the intention-to-treat principle: patients were analyzed in the group to which they were randomly assigned, whether or not they received the planned treatment. Time-to-event curves were calculated with the Kaplan–Meier method. The primary analysis used a Cox proportional-hazards model with the treatment group as the only variable. Where death could prevent the observation of other events, the researchers also used cumulative-incidence functions and Fine–Gray subdistribution hazard models. For cardiovascular death, noncardiovascular death counted as a competing event; for nonfatal outcomes, any death counted as a competing event. The proportional-hazards assumption was checked and held. There were no interim analyses and no adjustment for the multiple secondary outcomes, so confidence intervals around secondary outcomes should be interpreted cautiously.\u003c\/p\u003e\n\u003ch2 id=\"patient-results\"\u003ePatient characteristics and enrollment results\u003c\/h2\u003e\n\u003cp\u003eA total of 1,823 patients were randomized: \u003cstrong\u003e913 into the physiology-guided group\u003c\/strong\u003e and \u003cstrong\u003e910 into the angiography-guided group\u003c\/strong\u003e. Their baseline characteristics were well balanced between groups.\u003c\/p\u003e\n\u003cp\u003eKey baseline data for the physiology-guided group versus the angiography-guided group:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eMedian age: 67 years (interquartile range 58–76) versus 66 years (57–75)\u003c\/li\u003e\n\u003cli\u003eFemale: 223 patients (24.4%) versus 208 patients (22.9%)—overall, about 24% of the trial participants were women\u003c\/li\u003e\n\u003cli\u003eHypertension: 638 (69.9%) versus 614 (67.5%)\u003c\/li\u003e\n\u003cli\u003eDyslipidemia (high cholesterol): 482 (52.8%) versus 504 (55.4%)\u003c\/li\u003e\n\u003cli\u003eDiabetes: 195 (21.4%) versus 205 (22.5%)\u003c\/li\u003e\n\u003cli\u003eCurrent smoking: 292 (32.0%) versus 278 (30.5%)\u003c\/li\u003e\n\u003cli\u003ePrevious heart attack: 87 (9.5%) versus 98 (10.8%)\u003c\/li\u003e\n\u003cli\u003ePrevious PCI: 96 (10.5%) versus 105 (11.5%)\u003c\/li\u003e\n\u003cli\u003ePrevious stroke or transient ischemic attack: 33 (3.6%) versus 38 (4.2%)\u003c\/li\u003e\n\u003cli\u003eChronic kidney disease: 116 (12.7%) versus 127 (14.0%)\u003c\/li\u003e\n\u003cli\u003ePeripheral artery disease: 100 (11.0%) versus 106 (11.6%)\u003c\/li\u003e\n\u003cli\u003eCardiac arrest at presentation: 34 (3.7%) versus 32 (3.5%)\u003c\/li\u003e\n\u003cli\u003eKillip class II or higher (signs of heart failure, up to cardiogenic shock): 192 (21.0%) versus 171 (18.8%)\u003c\/li\u003e\n\u003cli\u003eMedian hemoglobin: 13.7 versus 13.9 g\/dl\u003c\/li\u003e\n\u003cli\u003eMedian creatinine clearance (a measure of kidney function): 85.2 versus 83.0 ml\/min\u003c\/li\u003e\n\u003cli\u003eMedian left ventricular ejection fraction (how well the heart pumps, as a percentage): 50.0 versus 50.0%\u003c\/li\u003e\n\u003cli\u003eLength of hospital stay: median 5.0 versus 5.5 days\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eMedications prescribed at discharge were also similar between groups. In the physiology-guided group compared with the angiography-guided group, aspirin was given to 890 patients (97.5%) versus 874 (96.0%), clopidogrel to 201 (22.0%) versus 195 (21.4%), ticagrelor to 623 (68.2%) versus 609 (66.9%), prasugrel to 82 (9.0%) versus 94 (10.3%), and oral anticoagulants to 86 (9.4%) versus 85 (9.3%). Most patients received an ACE inhibitor or ARB blood-pressure medication (86.5% versus 84.8%), a beta-blocker (76.5% versus 75.3%), and a statin (96.6% versus 96.5%). Additional lipid-lowering drugs included ezetimibe in 522 (57.2%) versus 525 (57.7%), bempedoic acid in 12 (1.3%) versus 18 (2.0%), and a PCSK9 inhibitor in 17 (1.9%) versus 14 (1.5%).\u003c\/p\u003e\n\u003cp\u003eThe assigned strategy was actually implemented in 886 patients (97.0%) in the physiology-guided group and in 871 patients (95.7%) in the angiography-guided group. Median follow-up was \u003cstrong\u003e17.9 months (interquartile range 12.0 to 24.0)\u003c\/strong\u003e. Clinical follow-up was complete for 98.9% of the physiology group and 99.2% of the angiography group—meaning almost no one was lost from the analysis.\u003c\/p\u003e\n\u003ch2 id=\"procedural-results\"\u003eProcedural details: what actually happened during treatment\u003c\/h2\u003e\n\u003cp\u003eThe two strategies changed what happened during the procedures. In the physiology-guided group, 1,332 total procedures were performed. The index procedure (the first, culprit-artery procedure) included PCI of a nonculprit vessel in only 115 of 913 patients (12.6%), while 419 staged procedures were performed, of which 397 (94.7%) included PCI of a nonculprit vessel. In the angiography-guided group, 1,590 procedures were performed, with nonculprit PCI during the index procedure in 197 of 910 patients (21.6%) and in 674 of 680 staged procedures (99.1%). The median time from the index procedure to the staged procedure was 3.0 days in the physiology-guided group versus 2.0 days in the angiography-guided group.\u003c\/p\u003e\n\u003cp\u003eArtery access was through the wrist (radial artery) in about 97% of procedures in both groups. The median amount of contrast dye used was lower with physiology guidance: 180 ml versus 223 ml. The culprit vessel was most often the left anterior descending artery or right coronary artery in both groups.\u003c\/p\u003e\n\u003cp\u003eThe measured nonculprit vessels in the physiology group were 1,147. Their locations and complexities were similar to those in the angiography group (1,128 vessels): left anterior descending artery 41.8% versus 41.9%, circumflex artery 30.7% versus 30.3%, and right coronary artery 27.6% versus 27.7%. Median reference diameter was 3.0 mm in both groups; median percent stenosis was 80% versus 79%. The severity of stenosis in the nonculprit vessels was also comparable, with most blockages (about 6 in 10) falling into the 70–89% range.\u003c\/p\u003e\n\u003cp\u003eMost importantly, in the physiology-guided group, the functional assessment succeeded in 1,132 of 1,147 vessels (98.6%); 15 vessels (1.3%) additionally required a wire-based FFR measurement because the imaging-based analysis could not be applied. The median FFR value was 0.80 (interquartile range 0.70–0.90). Based on the physiologic measurement:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e590 of 1,147 vessels (51.4%) were classified as functionally important (FFR 0.80 or less), and\u003c\/li\u003e\n\u003cli\u003e596 vessels (51.9%) were actually treated with PCI.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eThe virtual-PCI plan—derived from the FFR pullback curve—was implemented in 482 of the 596 treated lesions (80.8%). In contrast, the angiography-guided group treated virtually everything that looked narrow: PCI was performed on 1,071 of 1,128 nonculprit vessels (94.9%). This is the heart of the difference: physiology guidance avoided stenting in roughly half the arteries that the eye would have treated.\u003c\/p\u003e\n\u003ch2 id=\"primary-result\"\u003ePrimary finding: fewer major events with physiology-guided treatment\u003c\/h2\u003e\n\u003cp\u003eAt the time of the primary analysis, a primary-outcome event—the first occurrence of death from any cause, heart attack, stroke, transient ischemic attack, or ischemia-driven repeat revascularization—had occurred in:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e81 patients (8.9%)\u003c\/strong\u003e—about 9 of every 100—in the physiology-guided group, versus\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e125 patients (13.7%)\u003c\/strong\u003e—about 14 of 100—in the angiography-guided group.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eThe hazard ratio was 0.62 (95% confidence interval, 0.47 to 0.83; P\u0026lt;0.001). In plain language, patients in the physiology-guided group had roughly a 38% lower hazard (rate) of such events over time, compared with patients in the conventional angiography group. The P value below 0.001 means the probability that this difference occurred by chance is less than one in 1,000—an extremely robust result.\u003c\/p\u003e\n\u003cp\u003eThe \u003cstrong\u003enumber needed to treat was 21 (95% CI, 13 to 51)\u003c\/strong\u003e. That means approximately 21 patients would need to be treated with the physiology-guided strategy, instead of the visual strategy, to prevent one death, heart attack, stroke, or repeat revascularization event.\u003c\/p\u003e\n\u003cp\u003ePre-specified subgroup analyses—across age, sex, diabetes, and other factors—showed that the benefit appeared consistent. Additional sensitivity analyses, including analyses that excluded procedure-related heart attacks, also supported the main result.\u003c\/p\u003e\n\u003ch2 id=\"secondary-results\"\u003eSecondary results: heart attacks, strokes, and repeat procedures\u003c\/h2\u003e\n\u003cp\u003eThe secondary outcomes—the numbers below appear in the table as they were reported—also strongly favored the physiology-guided strategy, especially for heart attacks. Cardiovascular death or heart attack (combined) occurred in 52 patients (5.7%) versus 96 patients (10.5%), with a hazard ratio of 0.52 (95% CI, 0.37 to 0.73).\u003c\/p\u003e\n\u003cp\u003eLooking at individual outcomes:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eDeath from any cause: 36 patients (3.9%) versus 46 patients (5.1%); hazard ratio 0.77 (95% CI, 0.50 to 1.20). This difference did not reach statistical significance.\u003c\/li\u003e\n\u003cli\u003eCardiovascular death: 20 (2.2%) versus 31 (3.4%); HR 0.64 (95% CI, 0.36 to 1.12).\u003c\/li\u003e\n\u003cli\u003eNoncardiovascular death: 16 (1.8%) versus 15 (1.6%); HR 1.07 (95% CI, 0.53 to 2.17).\u003c\/li\u003e\n\u003cli\u003eAny myocardial infarction: 35 (3.8%) versus 73 (8.0%); HR 0.47 (95% CI, 0.31 to 0.70)—about a 53% lower rate of heart attacks.\u003c\/li\u003e\n\u003cli\u003eProcedure-related heart attack: 15 (1.6%) versus 33 (3.6%); HR 0.45 (95% CI, 0.24 to 0.83).\u003c\/li\u003e\n\u003cli\u003eSpontaneous (not procedure-related) heart attack: 21 (2.3%) versus 45 (4.9%); HR 0.46 (95% CI, 0.27 to 0.77).\u003c\/li\u003e\n\u003cli\u003eIschemic stroke: 3 (0.3%) versus 4 (0.4%); HR 0.75 (95% CI, 0.17 to 3.35). Strokes were rare; this difference could be due to chance.\u003c\/li\u003e\n\u003cli\u003eIschemia-driven repeat revascularization: 29 (3.2%) versus 47 (5.2%); HR 0.61 (95% CI, 0.38 to 0.97).\u003c\/li\u003e\n\u003cli\u003eStent thrombosis (clot in the stent): 6 (0.7%) versus 11 (1.2%); HR 0.54 (95% CI, 0.20 to 1.47)—again, the numbers were small, so this difference was not separately conclusive.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eThe reduction in heart attacks was not merely a matter of avoiding procedure-related events. Spontaneous heart attacks—events occurring on their own, away from any procedure—were also cut by more than half, which is a biologically meaningful signal that the physiology-guided strategy correctly identified dangerous, flow-limiting disease.\u003c\/p\u003e\n\u003ch2 id=\"safety-results\"\u003eSafety results: kidney injury and major bleeding\u003c\/h2\u003e\n\u003cp\u003eThe physiology-guided strategy was also, on balance, safer. The primary safety outcome—contrast-associated acute kidney injury or major bleeding (BARC type 3, 4, or 5)—occurred in \u003cstrong\u003e42 patients (4.6%)\u003c\/strong\u003e, about 5 of every 100, in the physiology-guided group, versus \u003cstrong\u003e65 patients (7.1%)\u003c\/strong\u003e, about 7 per 100, in the angiography-guided group. The hazard ratio was 0.63 (95% CI, 0.43 to 0.93; P=0.02).\u003c\/p\u003e\n\u003cp\u003eBreaking this down:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eContrast-associated acute kidney injury: 20 patients (2.2%) versus 36 patients (4.0%); HR 0.55 (95% CI, 0.32 to 0.94). The lower dye volume used in the physiology-guided group (median 180 ml versus 223 ml) probably helped protect the kidneys.\u003c\/li\u003e\n\u003cli\u003eMajor bleeding (BARC type 3, 4, or 5): 23 patients (2.5%) versus 33 patients (3.6%); HR 0.69 (95% CI, 0.41 to 1.18). Bleeding was less frequent in the physiology-guided group, although this component by itself did not reach statistical significance.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eThe reduced number of procedures, shorter or deferred planned stenting, and lower contrast exposure are likely explanations for the safety benefit.\u003c\/p\u003e\n\u003ch2 id=\"implications\"\u003eWhat this means for patients\u003c\/h2\u003e\n\u003cp\u003eFor patients who have had a STEMI and are discovered to have additional blockages, this trial offers a clear, practical message: treating every visible narrowing is not the best approach. Instead, using the physiology of blood flow—estimated through functional coronary angiography—to guide which arteries are stented leads to:\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003efewer major adverse events (about 5 fewer events per 100 patients over roughly 1.5 years),\u003c\/li\u003e\n\u003cli\u003eapproximately half the number of heart attacks,\u003c\/li\u003e\n\u003cli\u003efewer repeat procedures caused by renewed symptoms,\u003c\/li\u003e\n\u003cli\u003efewer safety events, especially contrast-related kidney injury, and\u003c\/li\u003e\n\u003cli\u003eless contrast dye overall during hospitalization.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eThe effect was consistent across the pre-specified subgroups. That gives cardiologists confidence that most types of STEMI patients—older and younger, male and female, with and without diabetes—derive the same relative benefit from the physiology-guided strategy.\u003c\/p\u003e\n\u003cp\u003eAvoiding an unnecessary stent has real downstream value. A stent, while life-saving for a critical blockage, carries risks of clotting, re-narrowing, the need for prolonged blood thinners, and procedural complications. In this trial, when the FFR estimate was above 0.80, leaving the lesion alone reduced events rather than increasing them—future heart attacks were actually less common. That is strong evidence that the eyes—even the trained eyes of an interventional cardiologist—are inferior to physiologic measurement in this setting.\u003c\/p\u003e\n\u003cp\u003eThe technology used here is also patient-friendly in an important sense. Functional coronary angiography required a pressure wire in only 1.3% of vessels. The whole FFR calculation was done offline (and, in future clinical practice, can be done in real time) using the same angiogram already obtained, without extra medication to stress the heart, without passing a wire across a delicate plaque, and without additional radiation.\u003c\/p\u003e\n\u003ch2 id=\"limitations\"\u003eLimitations of the study\u003c\/h2\u003e\n\u003cp\u003eThis trial has limitations that patients should understand before drawing firm conclusions.\u003c\/p\u003e\n\u003cp\u003eFirst, though the follow-up was complete for almost all patients, the median duration of observation was only 17.9 months. Long-term differences—whether the benefit persists, grows, or fades at 3 or 5 years—are not yet known.\u003c\/p\u003e\n\u003cp\u003eSecond, the trial was not blinded. Patients and doctors knew which treatment strategy was being used, which could theoretically influence later decisions such as the threshold for performing a repeat procedure. The fact that event adjudication was blinded reduces, but does not eliminate, this concern.\u003c\/p\u003e\n\u003cp\u003eThird, while the primary endpoint was highly significant, some secondary endpoints—including deaths and strokes—had wide confidence intervals and small event counts. The trial could not definitively prove that the physiology-guided strategy reduces death from any cause (HR 0.77; 95% CI, 0.50 to 1.20) or cardiovascular death (HR 0.64; 95% CI, 0.36 to 1.12). The hazard ratios suggest a possible mortality benefit, but chance cannot be excluded for those specific outcomes.\u003c\/p\u003e\n\u003cp\u003eFourth, because researchers did not adjust for multiple comparisons across secondary outcomes, a finding could appear statistically significant by chance. The authors explicitly caution that the confidence intervals for secondary outcomes should not be used to infer the size of treatment effects.\u003c\/p\u003e\n\u003cp\u003eFifth, the trial was conducted at 21 experienced, high-volume centers in Italy and Pakistan. Approximately three-quarters of the participants were men. Whether results would be identical in other health-care settings, or specifically in women (who made up 24% of this population), is less certain, although subgroups appeared consistent.\u003c\/p\u003e\n\u003cp\u003eFinally, the angiography-guided comparator is sometimes more aggressive than some community practice: it treated 94.9% of visually narrow vessels. That high rate of treatment is exactly the standard of care based on visual interpretation, but it may overstate the absolute benefit of physiology guidance compared with a more \"conservative\" physician who might already leave some moderate lesions alone. What the trial demonstrates is that functional guidance is better than a routine policy of visually guided complete revascularization.\u003c\/p\u003e\n\u003ch2 id=\"recommendations\"\u003ePractical recommendations\u003c\/h2\u003e\n\u003cp\u003eWhat can patients take from this study?\u003c\/p\u003e\n\u003col\u003e\n\u003cli\u003eIf you are hospitalized with a heart attack and told that additional blockages exist, ask your cardiologist whether a functional assessment—such as functional coronary angiography—will be used to decide which blockages actually need stents.\u003c\/li\u003e\n\u003cli\u003eUnderstand that having a blockage of 50–99% on the X-ray does not mean that stenting is always required. More than one-third (about 38%) of patients in the physiology-guided arm had no nonculprit stent placed, and these patients still did better overall than those who had all visible lesions stented.\u003c\/li\u003e\n\u003cli\u003eIf your doctor recommends leaving a moderate narrowing unstented because its measured FFR is above 0.80, the trial's results support that decision. It was associated with fewer heart attacks—not more—than stenting every narrowing would have been.\u003c\/li\u003e\n\u003cli\u003eAfter any heart attack, guideline-directed medical therapy remains vital. In both groups, more than 96% of patients were discharged on aspirin and a statin, and most received a second antiplatelet drug, a beta-blocker, and an ACE inhibitor or ARB. No stenting strategy can replace these medicines.\u003c\/li\u003e\n\u003cli\u003eThe safest approach to stenting after a heart attack is still the one that targets medically appropriate lesions. The physiological approach used less dye, produced fewer kidney injuries, and resulted in fewer repeat procedures.\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003cp\u003eThis is what high-quality randomized evidence looks like in modern cardiology. The AIR-STEMI trial should encourage hospitals to make functional coronary angiography a routine part of complete revascularization planning in STEMI patients with multivessel disease.\u003c\/p\u003e\n\u003c!-- ddn:faq:start --\u003e\n\u003ch2 id=\"ddn-faq\"\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003ch3\u003eAfter a STEMI heart attack, doctors found blockages in more than one of my heart arteries. How do they decide which additional blockages to stent?\u003c\/h3\u003e\n\u003cp\u003eIn the AIR-STEMI trial, doctors compared two ways to choose. One used functional coronary angiography, a computer method that estimates whether a narrowing truly limits blood flow. The other used traditional visual inspection alone. Treating only blockages with reduced flow led to fewer deaths, heart attacks, strokes, or repeat procedures than stenting every visible narrowing.\u003c\/p\u003e\n\u003ch3\u003eWhat is functional coronary angiography and does it require extra wires or medications?\u003c\/h3\u003e\n\u003cp\u003eFunctional coronary angiography estimates fractional flow reserve directly from standard angiogram images. It does not require threading a pressure wire across the blockage or giving extra drugs to stress the heart. In the AIR-STEMI trial, a pressure wire was needed for only about 1 in 100 vessels. The analysis can be done using images already taken.\u003c\/p\u003e\n\u003ch3\u003eIf my doctor says an additional blockage has a fractional flow reserve above 0.80, is it safe to leave it without a stent?\u003c\/h3\u003e\n\u003cp\u003eIn the AIR-STEMI trial, patients whose nonculprit blockages were left unstented because their estimated FFR was above 0.80 had fewer heart attacks and other events than patients who had every narrow-looking artery stented. About 38 percent of patients in the physiology-guided group had no additional stent placed, and they did better overall.\u003c\/p\u003e\n\u003ch3\u003eWhat were the main benefits of using functional coronary angiography after a heart attack in the AIR-STEMI trial?\u003c\/h3\u003e\n\u003cp\u003eAmong about 1,800 patients followed for roughly 18 months, the physiology-guided approach reduced major events from about 14 per 100 to about 9 per 100. Heart attacks were about half as frequent. Repeat procedures, contrast-related kidney injury, and the amount of dye used were also lower compared with treating all visible blockages.\u003c\/p\u003e\n\u003ch3\u003eDid the AIR-STEMI trial show that the physiology-guided approach reduced deaths?\u003c\/h3\u003e\n\u003cp\u003eThe trial found fewer deaths from any cause in the physiology-guided group, but that difference did not reach statistical significance. Cardiovascular death was also less frequent, yet chance could not be ruled out for those specific outcomes. The clearest benefits were fewer heart attacks and fewer repeat procedures, along with fewer safety events overall.\u003c\/p\u003e\n\u003ch3\u003eWhat were the safety results regarding the kidneys and bleeding in the AIR-STEMI trial?\u003c\/h3\u003e\n\u003cp\u003eThe combined safety outcome of contrast-associated acute kidney injury or major bleeding happened in about 5 of 100 patients with physiology guidance versus 7 of 100 with visual guidance. Kidney injury was significantly less common, likely because less contrast dye was used. Major bleeding was also less frequent, though that difference alone was not statistically significant.\u003c\/p\u003e\n\u003ch3\u003eAre the AIR-STEMI results applicable to women, older adults, and people with diabetes?\u003c\/h3\u003e\n\u003cp\u003eThe trial enrolled patients with STEMI and multivessel disease, including about 24 percent women. Pre-specified subgroup analyses across age, sex, and diabetes showed the benefit of physiology-guided treatment appeared consistent. However, most participants were men, and the trial was conducted at experienced centers in two countries, so results may differ in other health-care settings.\u003c\/p\u003e\n\u003ch3\u003eI had a heart attack and have several blockages. My cardiologist recommends stenting all of them. Should I get a second opinion on whether all blockages really need stents?\u003c\/h3\u003e\n\u003cp\u003eIn a large international trial of STEMI patients with multivessel disease, routine stenting of all visually significant nonculprit blockages was compared with using functional coronary angiography, which estimates whether each narrowing truly limits blood flow. The physiology-guided approach treated only about half the blockages and led to roughly half the heart attacks, fewer repeat procedures, lower contrast dye exposure, and less kidney injury. Because the visual-angiography strategy may overtreat harmless narrowings, a second opinion can help determine whether functional assessment should guide stent decisions. Diagnostic Detectives Network provides independent expert second opinions.\u003c\/p\u003e\n\u003c!-- ddn:faq:end --\u003e\n\n\u003ch2 id=\"source\"\u003eSource Information\u003c\/h2\u003e\n\u003cp\u003eThis patient-friendly article is based on peer-reviewed research originally published in \u003cem\u003eThe New England Journal of Medicine\u003c\/em\u003e. Original article: \"Complete Revascularization Guided by Functional Coronary Angiography in STEMI,\" by S. Biscaglia, A. Erriquez, I. Colaiori, and colleagues, for the AIR-STEMI Trial Investigators (published August 29, 2026; DOI: 10.1056\/NEJMoa2605373). Copyright © 2026 Massachusetts Medical Society.\u003c\/p\u003e\n\u003cp\u003eThe original authors report relationships with device and imaging companies, including Sahajanand Medical Technologies, Pulse Medical Imaging Technology, and Pie Medical Imaging, as described in the journal article. The trial was sponsored by the Italian Health Ministry and administered by the University Hospital of Ferrara. Trial registration: ClinicalTrials.gov number, NCT05818475.\u003c\/p\u003e","brand":"DiagnosticDetectives.Com","offers":[{"title":"Default Title","offer_id":47576713363612,"sku":null,"price":0.0,"currency_code":"USD","in_stock":true}],"url":"https:\/\/diagnosticdetectives.com\/de\/products\/choosing-the-right-blockages-to-fix-after-a-heart-attack-the-air-stemi-trial","provider":"DiagnosticDetectives.Com","version":"1.0","type":"link"}