Sent Home Again With Normal Tests: What to Do Next

“Everything looks normal” is not a diagnosis. After the third emergency department visit with chest pain and an unremarkable ECG, a normal troponin, and a stress test report saying no significant ischemia, the label a woman carries home is reassurance, not an explanation. The problem is that the tests performed were designed to answer one specific question: is there an obstructive blockage in a major coronary vessel? That question can have a normal answer while a different form of coronary disease, one the tests were never designed to detect, is producing every symptom she was sent home from.

The Mechanism

The coronary circulation consists of two functionally distinct compartments. The epicardial arteries, large enough to see on angiography and CT, are the vessels standard cardiac testing was built to evaluate. The microvasculature, comprising arterioles and capillaries below the resolution limit of any imaging catheter, handles the distribution of blood through the myocardium itself and regulates flow in real time through active vasodilation and vasoconstriction.

Standard cardiac testing is calibrated for the first compartment. A nuclear stress test detects the regional flow mismatch produced by a fixed obstruction of 50 percent or more in a major epicardial vessel: the ischemic territory does not take up tracer at the same rate as the normal territory, producing a visible defect. A standard exercise stress echocardiogram looks for wall motion abnormalities produced by the same mechanism. Conventional coronary angiography images the epicardial vessels and documents stenosis.

None of these tests was designed to measure how well the microvasculature dilates in response to demand, whether the endothelium of the small vessels generates adequate nitric oxide for vasodilation, whether the small or large vessels constrict abnormally in response to stimuli (vasospasm), or whether subendocardial ischemia is occurring below the threshold of transmural ST changes. Each of those failures is invisible to the standard evaluation because each operates in the functional domain that standard tests do not measure. 4 / Promising

Vasospastic angina, which involves transient intense vasoconstriction of the epicardial or small coronary vessels, produces chest pain and ECG changes during the spasm that completely resolve when the spasm terminates. The angiogram performed at rest, between episodes, shows entirely normal or minimally diseased vessels. The coronary angiogram is accurate. The disease is real. These two facts coexist because the disease is in the behavior of the vessels under stress, not in their resting anatomy.

Microvascular dysfunction, detailed in the companion article on this platform, adds a further layer. When the small vessels fail to vasodilate adequately under demand, the coronary flow reserve falls below normal and the myocardium experiences ischemia during exertion or stress while the epicardial anatomy remains open. The nuclear stress test may show no defect if the ischemia is diffuse rather than regional, patchy, or subendocardial rather than transmural. The exercise ECG may be non-diagnostic because the electrical changes produced are too subtle or too diffusely distributed to produce the localized ST depression the test is calibrated to detect.

The correct clinical interpretation of a negative standard workup is: obstructive coronary artery disease has been evaluated and is not the primary diagnosis. The functional behavior of the coronary circulation has not been evaluated. These are different statements, and the difference between them is the entire diagnostic gap that produces years of recurrent chest pain with normal test results.

What the Evidence Shows

The Women’s Ischemia Syndrome Evaluation (WISE) study, a National Heart, Lung, and Blood Institute-funded prospective cohort study begun in 1996, enrolled women referred for coronary angiography for chest pain symptoms. The majority of enrolled women, approximately two-thirds, were found to have non-obstructive coronary arteries on angiography. 4 / Promising The study was designed specifically to characterize what was happening to these women, because clinical practice at the time largely treated the non-obstructive result as an all-clear.

The WISE long-term follow-up data overturned that assumption. Shaw and colleagues published five-year outcomes data in the Journal of the American College of Cardiology in 2006 showing that women with non-obstructive coronary arteries and persistent chest pain had significantly elevated rates of major adverse cardiovascular events compared with asymptomatic women enrolled as controls. Hospitalization rates were higher, quality of life scores were substantially lower, and cardiac mortality was elevated compared with what the “normal angiogram” label had implied. The women in the non-obstructive chest pain group were not fine. They had a disease that the standard evaluation had mislabeled as absence of disease.

The WISE investigators, including Bairey Merz and colleagues, also documented that abnormal coronary flow reserve, measurable during catheterization, was present in a significant proportion of the non-obstructive group and correlated with symptom burden and adverse outcomes. The mechanism was physiologically demonstrable in the patients who had the right tests performed. The test that produced the normal result was simply the wrong test for the disease present.

The CorMicA trial, published by Berry and colleagues in JACC Cardiovascular Interventions in 2019, enrolled 151 patients with angina and non-obstructive coronary arteries and randomly assigned them to stratified medical therapy based on coronary function testing results or to conventional management. At 12 months, the stratified therapy group had significantly lower angina frequency and better Seattle Angina Questionnaire scores compared with controls. The trial demonstrated that identifying the specific functional diagnosis, microvascular versus vasospastic versus combined, and treating to that specific mechanism changed clinical outcomes compared with managing all non-obstructive chest pain the same way. 4 / Promising

The COVADIS group (Coronary Vasomotion Disorders International Study Group), an international consortium that published standardized diagnostic criteria for vasospastic and microvascular angina in 2018, formalized the clinical framework for diagnosing INOCA. Their criteria require provocation testing with acetylcholine to diagnose vasospastic angina definitively, and coronary flow reserve and index of microcirculatory resistance measurement to diagnose microvascular dysfunction. These diagnostic categories were not clinically operational in most centers before this framework existed. The patients who spent years cycling through normal results often did so in an era when the diagnostic tools existed but the clinical pathway for using them had not been established.

Non-obstructive plaque is a further consideration that standard angiography may miss. Coronary CT angiography can detect plaque burden in vessel walls that has not yet produced stenosis visible on invasive angiography. The PROMISE trial (Douglas and colleagues, New England Journal of Medicine, 2015) and subsequent analyses of coronary CTA data have documented that non-obstructive plaque on CTA, even without significant stenosis, is associated with increased cardiovascular event rates. A woman who has had standard catheterization showing clean arteries but has not had coronary CTA may have non-obstructive atherosclerotic plaque that informs both her risk stratification and her treatment.

The Label Accumulation Problem

One of the most consistent barriers for women cycling through normal results is that each normal result functions as a case closure rather than a differential-narrowing step. A negative stress test becomes “your heart is fine.” A normal angiogram becomes “you don’t have heart disease.” These conclusions are accurate statements about what was tested. They are wrong as descriptions of what is known about her coronary function.

The problem compounds when non-cardiac diagnoses fill the explanatory vacuum. Anxiety, costochondritis, gastrointestinal reflux, and musculoskeletal chest wall pain are all real conditions and all produce real chest pain. They are also diagnoses that are convenient to reach when the cardiac testing has been negative, the patient keeps coming back with symptoms, and the clinical team does not have a further cardiac pathway to offer. Once these diagnoses exist in the chart, they acquire momentum. New symptoms get filed under existing labels.

The clinical distinction worth preserving is between diagnoses that were reached by ruling out alternatives and diagnoses that were reached by not testing the alternatives. Anxiety as a diagnosis after a full cardiac workup has been completed and returned normal results is a legitimate clinical conclusion. Anxiety as a diagnosis applied because the initial ECG was normal is a hypothesis being used as a conclusion.

A woman who can articulate this distinction to her treating clinician has a more productive conversation than one who disputes the test results. The question is not whether the ECG was read correctly. It is whether coronary function testing has been part of the evaluation.

Provocative Coronary Function Testing: What the Catheterization Protocol Actually Involves

For women with recurrent chest pain and a negative standard workup, the next diagnostic step — when available at an appropriately equipped center — is coronary function testing performed during cardiac catheterization. This is not automatically included in a standard diagnostic angiogram. It requires specific protocols, specific pharmacological agents, and the operator must be performing the procedure with functional evaluation as the explicit goal rather than purely anatomical documentation.

The vasospastic component is evaluated with intracoronary acetylcholine provocation. After the angiogram documents the absence of obstructive disease, acetylcholine is infused at escalating doses — typically 2 to 100 micrograms — into the coronary arteries. In normal endothelium, acetylcholine causes vasodilation through muscarinic receptor activation. In vessels with endothelial dysfunction or heightened smooth muscle sensitivity, the same infusion causes paradoxical vasoconstriction or frank spasm. The test is positive for epicardial vasospasm when the intracoronary infusion produces chest pain, ECG changes, and more than 90% focal reduction in coronary diameter — reproducing the patient’s symptoms in a controlled, reversible setting. Microvascular spasm is documented when symptoms and ECG changes occur without focal epicardial narrowing, indicating that the abnormal vasomotor response is in the small vessels below angiographic resolution.

Microvascular function is evaluated through coronary flow reserve (CFR) and index of microcirculatory resistance (IMR). Coronary flow reserve is the ratio of hyperemic to resting coronary flow, measured after intracoronary adenosine or papaverine maximally dilates the microvasculature. A CFR below 2.0 to 2.5 indicates impaired microvascular vasodilatory capacity. Fearon and colleagues, reporting in Circulation in 2010, validated the IMR — a pressure-wire-based measure of minimum microvascular resistance — as a reproducible catheterization-based index of microcirculatory function that independently predicts clinical outcomes. The WISE Coronary Vascular Dysfunction substudy, published by Pepine and colleagues in JAMA in 2010, documented that impaired coronary flow reserve was present in a significant proportion of women with non-obstructive coronary disease and correlated independently with symptom burden and adverse long-term cardiovascular outcomes.

The result of a complete coronary function evaluation is not “normal arteries.” It is a functional diagnosis: epicardial vasospasm, microvascular dysfunction, or both. These diagnoses carry specific treatment implications — calcium channel blockers and nitrates for vasospasm, statins and ACE inhibitors targeting endothelial function for microvascular disease — that are distinct from each other and from the management of obstructive coronary artery disease. The test makes the distinction possible. Without it, treatment remains empirical where mechanism-guided therapy is available.

What to Do This Week

1. Collect every cardiac test report you have received and read what each one actually evaluated. Confirm whether each test was a standard exercise ECG test, a nuclear imaging study, an echocardiographic stress study, or a coronary angiogram. Ask specifically: was a perfusion imaging test done, and what did it show? Was the catheterization a standard diagnostic angiogram, or did it include coronary flow reserve measurement and acetylcholine provocation? “Cardiac test” is not a precise enough category to know what was found.

2. Ask your cardiologist directly whether microvascular angina and vasospastic angina have been specifically considered and whether the testing needed to evaluate them has been done. These require CFR and IMR measurement and acetylcholine provocation testing respectively. If your cardiologist is unfamiliar with these tests or uncertain whether your center performs them routinely, that is important clinical information.

3. Ask about coronary CT angiography if you have not had it and have only had standard invasive angiography. CT angiography evaluates plaque burden in the vessel wall, including non-obstructive plaque that invasive angiography may under-represent, and adds anatomical information about your coronary disease burden even when stenosis is absent.

4. Look for a center with an INOCA or women’s heart program if your current clinical team has completed the standard evaluation and reached a dead end. Academic medical centers, and an increasing number of specialized cardiac programs, have dedicated clinical pathways for evaluating non-obstructive ischemia. The tests required, acetylcholine provocation and CFR/IMR measurement, require a center that performs them routinely and interprets them in clinical context. A center that can technically perform catheterization is not the same as a center with experience in INOCA evaluation.

5. When you see a new clinician, provide a precise summary: “I have had recurring chest pain for X years. I have had a standard stress test [and/or nuclear stress test and/or coronary angiogram]. Each returned results showing no obstructive coronary artery disease. Microvascular angina and vasospastic angina have not been formally evaluated.” This framing tells the clinician what has been done, what it showed, and what remains unanswered, without requiring them to interpret the prior workup from memory or a stack of records.

Recurring chest pain with normal standard tests is a clinical presentation with a real diagnosis on the other side of the right question. The question the tests have answered, whether obstructive coronary artery disease is present, is not the only coronary question worth asking. The question that has not been answered, whether the coronary circulation functions normally under demand, stress, and vasoconstrictive stimuli, is the one that explains why the symptoms keep coming back. It has an answer. The answer requires the test that has not yet been ordered.