This research aims to investigate whether symptoms of chest pain or shortness of breath among the study population are arising due to a heart problem, particularly any reduction of blood flow to the heart muscle from blockages in the coronary blood vessels or inflammation of the heart using cardiac magnetic resonance imaging that measures the amount of blood flow during a stress state meant to simulate vigorous exercise. At present, doctors use standard magnetic resonance imaging pictures of blood flow patterns to treat heart disease. The investigators want to study if detailed blood flow measurements, in addition to the standard blood flow pattern, could diagnose heart disease more accurately and allow more doctors to understand the severity of heart disease. Early research has demonstrated that detailed blood flow measurements may be more accurate in diagnosing heart disease in some patients, but doctors need more information to know how to use these measurements.

In this proposal of the Multicenter Stress Cardiac Magnetic Resonance Quantitative Perfusion Imaging in the United States (SPINS2) study, the investigators seek to assess the prognostic utility of myocardial blood flow and flow reserve by quantitative stress cardiac magnetic resonance imaging compared to patients with normal quantitative perfusion indices. The investigators hypothesize that patients with abnormal myocardial blood flow and flow reserve will have higher adverse cardiac events, incremental to demographic risks and qualitative perfusion, and they should be considered for invasive workup or early institution of goal-directed medical therapies. In addition, the investigators hypothesize that quantitative perfusion by cardiac magnetic resonance imaging will characterize the myocardial extent and severity of multivessel disease and the participants' risk of adverse cardiac outcomes.

Patients with chest pain syndromes and suspected ischemic heart disease who meet both inclusion and exclusion criteria will be prospectively recruited among 20 sites across the United States over the course of 1.5 years. Participants will receive standardized quantitative stress cardiac magnetic resonance imaging protocol with Gadavist (Bayer, Germany) 0.05 mmol/kg dose for each stress and rest perfusion imaging (total dose of 0.1 mmol/kg) as per Food and Drug Administration (FDA)-approved indication. All participants will receive vasodilator stress with regadenoson or adenosine depending on local site practice. A single (7-10 ml tube) whole blood sample will be collected from each patient for processing of blood biomarkers.

All participants will have demographics and imaging characteristics recorded at baseline visits. Follow-up will occur via email or telephone at 3 months, 12 months, and 24 months from baseline. At each follow-up visit, medications, treatment, and adverse events will be recorded. In addition, all available electronic patient records will be reviewed in detail to capture all follow-up data which will be entered into an outline database using clearly defined data definitions. Participants will be followed for a total of 2 years from baseline cardiac magnetic resonance imaging study.

Inclusion Criteria:

1. male or female at age 35-85 years,

2. presence of either of the following sign/symptom that led to a referral to stress cardiac magnetic resonance imaging:

   1. chest pain or anginal equivalent, or
   2. abnormal electrocardiogram with a suspicion of coronary artery disease

3. Intermediate or high risk of significant coronary disease based on at least 1 of the following conditions:

   a) patient age > 45 for male, 50 for female b) Diabetes, hypertension, or hypercholesterolemia: by either history or medical treatment c) family history of premature coronary disease: first degree relative at age <= 55 male and <=65 female d) history of smoking of > 10 packed-years e) post-menopausal state >5 years f) any chronic inflammatory conditions d) Body mass index > 30 e) Any medical documentation of coronary or peripheral artery disease

Exclusion Criteria:

1. Acute myocardial infarction within the past 30 days prior to cardiac magnetic resonance imaging

2. Confirmed diagnosis of any significant non-coronary cardiac conditions below:

   1. any severe-grade valvular heart disease,
   2. left ventricular ejection fraction <40% from any known non-coronary causes,
   3. infiltrative cardiomyopathy,
   4. hypertrophic cardiomyopathy,
   5. pericardial disease with significant constriction, or

3. active pregnancy,

4. any competing conditions leading to an expected survival of < 2 years

5. contraindication to vasodilator (regadenoson or adenosine)

6. metallic device or object that poses an magnetic resonance imaging safety hazard

7. metallic device with a high likelihood of non-diagnostic cardiac magnetic resonance images