Városmajor Heart and Vascular Centre, Cardiac CT Working Group, Budapest, Hungary
September 29, 2026
History
Why did the patient come for a CT exam?
A 63-year-old female patient, presenting with typical chest pain, was referred for coronary imaging to clarify her coronary status and exclude acute coronary syndrome.
Laboratory tests showed marked myocardial injury and neurohormonal activation, with highly elevated high-sensitivity troponin I of 2032 ng/L, CK of 565 U/L, CK-MB of 43 U/L, and NT-proBNP of 1589.7 pg/mL.
Mild inflammatory activity was also present, with leukocytosis of 12.86 G/L, neutrophilia, and mildly elevated CRP of 6.2 mg/L. Renal function was preserved, with an eGFR of 107 mL/min.
An initial transthoracic echocardiography showed mildly to moderately reduced global left ventricular systolic function, with a left ventricular ejection fraction of 42% by Simpson’s method. Regional wall motion abnormalities were present, with hypokinesis of the midventricular segments and near akinesia of the apical third of the left ventricle. Mild mitral regurgitation and moderate tricuspid regurgitation were present.
Right ventricular size was normal, and right ventricular longitudinal systolic function was preserved. The estimated pulmonary artery systolic pressure was mildly elevated.
Coronary CT angiography (CCTA) was recommended to exclude obstructive coronary artery disease.
Diagnosis
What were the CT findings, and what happened to the patient after CT?
Coronary CT angiography was performed using a dual-source photoncounting detector CT scanner (Siemens NAEOTOM Alpha Peak).
The estimated CCTA radiation dose was 397 mGy·cm. Iomeron 400 was administered with a contrast volume of 90 mL and a flow of 5.5 ml/s. The patient received 0.8 mg sublingual nitroglycerin prior to the examination. Heart rate during the scan was 93–97/min with sinus rhythm.
The coronary calcium score was 4.
The patient had a left-dominant coronary artery system and normal origin and course of the coronary arteries. No relevant coronary atherosclerosis or luminal stenosis were detected. Only minimal vessel wall irregularities were observed, with small specks of calcified plaque in the distal left anterior descending (LAD) artery (Figure 1. and 2.)
Figure 1. CT coronary angiography demonstrating
normal coronary artery anatomy with no
evidence of a significant stenosis.
Figure 2. Electrocardiogram (ECG) during Prospective
Sequential Cardiac CT Acquisition.
Coronary CT angiography was performed using a prospectively ECG-triggered sequential axial acquisition. Given the patient’s heart rate, exceeding 90 beats/min, multiphase image reconstruction was performed to ensure optimal image quality and to allow simultaneous assessment of coronary anatomy and left ventricular function.
In addition to coronary artery evaluation, the multiphase datasets were analyzed for regional wall-motion abnormalities and cardiac chamber volumetry.
Coronary analysis demonstrated non-obstructive coronary artery disease, with only minimal calcified plaque in the distal left anterior descending artery. Functional assessment revealed severe apical hypokinesis/akinesis with associated midventricular dyskinesis and preserved basal contractility, resulting in the characteristic apical ballooning pattern of a classical Takotsubo syndrome (Figure 3).
Figure 3. Left Ventricular Apical Dysfunction Consistent with Takotsubo Pattern on Multiphase Cardiac CT Functional
Analysis. Multiphase cardiac CT-derived left ventricular wall-motion bull’s-eye map demonstrating a regional
gradient of myocardial contractility with preserved basal function (red–yellow), reduced mid-ventricular motion,
and markedly impaired apical wall motion (blue–purple). The pattern shows an apical-dominant distribution of
dysfunction, consistent with a classical Takotsubo-type contraction abnormality in the appropriate clinical context
(left). Mildly increased left ventricular end-diastolic and end-systolic volume indices (indexed to body surface area)
were detected, with mildly reduced systolic function (LVEF 45%) based on the available cardiac phases.
Mildly increased left ventricular end-diastolic and end-systolic volume indices were detected, with mildly reduced systolic function (LVEF 45%).
As an incidental extracardiac finding, scattered bilateral ground-glass opacities with patchy consolidations were detected, most consistent with bronchopneumonia given the elevated inflammatory laboratory markers.
Comments
Is there any clinically interesting aspect of the case to discuss?
What difference did photon-counting CT make for the patient?
This case highlights the clinical value of the photon-counting coronary CT angiography in the diagnostic work-up of patients presenting with acute chest pain, elevated cardiac biomarkers, and electrocardiographic changes suggestive of acute coronary syndrome.
Beyond excluding obstructive coronary artery disease, CT angiography enables comprehensive myocardial functional assessment, allowing identification of the characteristic apical ballooning pattern consistent with Takotsubo syndrome, thereby supporting a working diagnosis of MINOCA – now defined as myocardial injury with non-obstructive coronary arteries (Fifth Universal Definition of Myocardial Infarction, 2026) – with Takotsubo syndrome as the most likely final diagnosis.
The ability of photon-counting CT to simultaneously evaluate coronary anatomy, plaque burden, and left ventricular function in a single examination may facilitate rapid differentiation between obstructive coronary disease and alternative causes of acute myocardial injury, potentially reducing the need for additional imaging or invasive angiography in selected patients.
This case also demonstrates the technical advantages of photoncounting coronary CT angiography for combined coronary and functional cardiac assessment in an acute setting.
The system provides excellent spatial and temporal resolution, enabling high-quality coronary plaque evaluation, even at elevated heart rates (>90 beats/min), with minimal motion artefact. This allows for a reliable assessment of the coronary lumen and detection of only minimal calcified plaque in the distal LAD.
In addition, multiphase ECG-gated reconstructions offer excellent temporal resolution for detailed motion analysis of all cardiac chambers, permitting accurate depiction of regional wall-motion abnormalities.
Overall, the combination of high spatial fidelity for plaque characterization and high temporal resolution for functional assessment underscores the robustness of photon-counting CT for integrated “one-stop” coronary and myocardial evaluation, even under challenging heart rate conditions.
Note that the role of CT in this case should be interpreted within its limits. CCTA was requested to rule out obstructive coronary artery disease in a haemodynamically stable patient; because of the elevated heart rate, a multiphase acquisition was used, which additionally depicted the wall-motion pattern. CCTA can therefore exclude obstructive coronary artery disease and further reinforce echocardiographic findings suggestive of Takotsubo syndrome, but it does not establish the diagnosis on its own. Current recommendations advise cardiac magnetic resonance imaging when the final diagnosis remains uncertain—particularly in the presence of inflammatory red flags—and follow-up echocardiography to document recovery of left ventricular function. In our patient, who was referred to our centre for CT only, further diagnostic work-up and follow-up were performed at the referring institution.
Examination Protocol
Scanner | NAEOTOM Alpha.Peak |
Scan area | Heart |
Scan mode | QuantumPlus |
Scan length | 126 mm |
Scan direction | Cranio-caudal |
Scan time | 2,38 s |
Tube voltage | 140 kV |
IQ level | 65 |
Dose modulation | CARE Dose4D |
CTDIvol | 31.5 mGy |
DLP | 397 mGy*cm |
Rotation time | 0.25 s |
Pitch | not applicable |
Slice collimation | 0.4 mm |
Slice width | 0.4 mm |
Reconstruction increment | 0.4 mm |
Reconstruction kernel | Bv56 Q4 |
keV level | 55 |
Spectral reconstruction | Monoenergetic Plus |
Heart rate | 95/min |
Contrast | Iomeron 400, 400 mg/mL |
Volume | 95 mL + 10mL saline pacer + 30mL saline chaser |
Flow rate | 5.5 mL/s |
Start delay | Bolus tracking triggered at 140 HU (CCTA) |
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The statements by customers of Siemens Healthineers described herein are based on results that were achieved in the customer’s unique setting. Because there is no “typical” hospital and many variables exist (e.g., hospital size, case mix, level of IT and/or automation adoption) there can be no guarantee that other customers will achieve the same results.
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