Left Ventricular Functional Parameters and Geometric Patterns in Korean Adults on Coronary CT Angiography with a 320-Detector-Row CT Scanner

[Using CT to Evaluate Cardiac Function]

A comprehensive evaluation of cardiac function includes information in relation to cardiac output and systemic venous return. The heart is composed of four chambers: two atria and two ventricles, each with its own unique mechanical function. These four cardiac chambers, their valves, and the pulmonary circulation system are inter-related as they preload or afterload on each other. Cardiac dysfunction is a failure of global cardiac function, resulting in typical clinical manifestations. To investigate the underlying cause of cardiac dysfunction, a step-by-step evaluation of cardiac blood flow tracks is necessary. In this context, imaging markers showing details of the cardiac structures have an important role in assessing cardiac function. An image-based evaluation allows for investigation of function in terms of individual cardiac components. Evaluation of cardiac function using cardiac CT has recently been validated. This review aimed to discuss cardiac CT-based imaging markers for comprehensive and detailed cardiac function assessment.

Relation of the left ventricular geometric patten to coronary artery disease in hypertensive patients using a 320-detector-row CT scanner

BACKGROUND

It was estimated that about 1.3 billion people were diagnosed to be hypertensive in 2015. All countries consistently show this high prevalence. Ischemic heart disease stands as the most common cause of systolic blood pressure-related deaths per year. Left ventricular hypertrophy determined by echocardiography can predict cardiovascular morbidity and mortality. The question of whether the LV geometric pattern has an additional prognostic value is still not clearly answered. Currently, coronary computed tomography is widely used in clinical practice with a great capability of simultaneous evaluation of the LV mass and the coronary arterial tree. Our study aims to examine the relationship between LV mass and geometry and coronary artery disease using an ECG-gated 320-detector- row CT scanner.

RESULTS

Two hundred ninety-eight hypertensive Egyptian individuals were enrolled in our study, the mean age was 57.5 ± 10.5, and males comprised 76.5% of the study population. The mean LV mass and LV mass index were 193 ± 60 gm and 95.2 ± 27.5 g/m² respectively. One-fifth of the patient had CAD luminal stenosis ≥ 50%. Normal LV geometric pattern was observed in about 37% of the study population. About one-third of the patients showed concentric remodeling. Patients with increased LV mass index represented one-third of the study population with a greater percentage of the concentric hypertrophy pattern than the eccentric hypertrophy pattern. Patients with high CAD-RADS showed statistically significant higher LV mass, LV mass index, and septal wall thickness. Patients with high CAD-RADS showed a greater percentage of concentric and eccentric hypertrophy. The LV geometric pattern was the only independent predictor of the high CAD-RADS. The LV geometric patterns associated with high RADS ordered from the highest to the lowest, were concentric LVH, Eccentric LV, and concentric remodeling.

CONCLUSIONS

LV geometric pattern is the only independent predictor of high CAD-RADS after adjustment for LV mass index and septal wall thickness. Among abnormal LV geometric patterns, concentric hypertrophy stands as the most important predictor of high CAD-RADS.

PRECAUTION IN THE USE OF EFFECTIVE DOSE IN CORONARY CT ANGIOGRAPHY

The effective dose is a quantity used in clinical practice for statistical evaluation of the radiation dose of patients undergoing different types of examinations. Coronary computed tomography angiography (CCTA) is a specific examination whose calculated effective dose may be subject to several biases. For this reason, it is important to consider factors (different examination techniques, heart rate and patient habitus) that may influence its resulting value. Another critical factor is the methodological procedure for calculating the effective dose and cardiac-specific coefficient used to estimate effective dose from the dose-length product in computed tomography. Because CCTA is increasingly used in cardiology, it is recommended that the chest coefficient be replaced with a new cardiac coefficient when calculating the effective dose.

Posterior myocardial infarction caused by superdominant circumflex occlusion over an absent right coronary artery: Case report and review of literature

RATIONALE

Congenital agenesis of the right coronary artery (CARCA) initially presenting as acute myocardial infarction (AMI) due to total occlusion is a rare clinical condition that can lead to severe complications, including death. We report a case of successful percutaneous coronary intervention (PCI) in a patient with this condition.

PATIENT CONCERNS

A 57-year-old man was admitted to our center with chest pain that had occurred several hours prior. Since he was initially diagnosed with AMI with ST-segment elevation, we promptly commenced coronary angiography (CAG).

DIAGNOSIS

CAG revealed the absence of a right coronary artery (RCA). In the left coronary cusp area, the left circumflex coronary artery (LCX) was occluded totally.

INTERVENTIONS

We performed PCI for total occlusion of the proximal part of the LCX. Follow-up CAG showed a superdominant branch of the LCX, sprouting into the RCA territory.

OUTCOMES

The patient was discharged uneventfully after successful PCI.

LESSONS

CARCA with AMI, which is an extremely unusual case, can be fatal; however, PCI seems to be an effective treatment option.

Congenital absence of the right coronary artery with acute myocardial infarction: report of two cases and review of the literature

Congenital absence of the right coronary artery (RCA) is a rare coronary anomaly. Few cases of this condition have been reported. Congenital absence of the RCA is considered as a benign anomaly. However, in certain cases, these patients may develop life-threatening clinical complications that include acute myocardial infarction, stroke, or sudden death. We report two patients who were diagnosed with congenital absence of the RCA and presented with acute myocardial infarction. We discuss our experience in diagnosis and treatment of this disease. Congenital absence of the RCA with acute myocardial infarction is an uncommon clinical emergency. Therefore, early detection, correct diagnosis, and appropriate treatment are important.

Cardiac CT angiography: normal and pathological anatomical features-a narrative review

The normal and pathological anatomy of the heart and coronary arteries are nowadays widely developed topics and constitute a fundamental part of the cultural background of the radiologist. The introduction of cardiac ECG-gated synchronized CT scanners with an ever-increasing number of detectors and with increasingly high structural characteristics (increase in temporal resolution, increase in contrast resolution with dual-source, dual energy scanners) allows the virtual measurement of anatomical in vivo structures complying with heart rate with submillimetric precision permitting to clearly depict the normal anatomy and follow the pathologic temporal evolution. Accordingly to these considerations, cardiac computed tomography angiography (CCTA) asserts itself as a gold standard method for the anatomical evaluation of the heart and permits to evaluate, verify, measure and characterize structural pathological alterations of both congenital and acquired degenerative diseases. Accordingly, CCTA is increasingly used as a prognostic model capable of modifying the outcome of diseased patients in planning interventions and in the post-surgical/interventional follow-up. The profound knowledge of cardiac anatomy and function through highly detailed CCTA analysis is required to perform an efficient and optimal use in real-world clinical practice.

Clinical Applications of Wide-Detector CT Scanners for Cardiothoracic Imaging: An Update

Technical developments in multidetector computed tomography (CT) have increased the number of detector rows on the z-axis, and 16-cm wide-area-coverage CT scanners have enabled volumetric scanning of the entire heart. Beyond coronary arterial imaging, such innovations offer several advantages during clinical imaging in the cardiothoracic area. The wide-detector CT scanner markedly reduces the image acquisition time to less than 1 second for coronary CT angiography, thereby decreasing the volume of contrast material and radiation dose required for the examination. It also eliminates stair-step artifacts, allowing robust improvements in myocardial function and perfusion imaging. Additionally, new imaging techniques for the cardiothoracic area, including subtraction imaging and free-breathing scans, have been developed and further improved by using the wide-detector CT scanner. This article investigates the technical developments in wide-detector CT scanners, summarizes their clinical applications in the cardiothoracic area, and provides a review of the recent literature.

Effects of epicardial adipose tissue volume and density on cardiac structure and function in patients free of coronary artery disease

PURPOSE

To determine the association of epicardial adipose tissue (EAT) volume and density with cardiac geometry and function.

METHODS

We included 178 consecutive patients who performed coronary computed tomography angiography but were not diagnosed with coronary artery disease (CAD). The EAT volume, density, and following cardiac structure and function parameters were measured: left ventricular ejection fraction, left ventricular mass (LVM), left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), left ventricular stroke volume (LVSV), left ventricular end-diastolic diameter (LVEDD), interventricular septal thickness (IVST) and posterior wall thickness (PWT). All the parameters were standardized using the height^2.7.

RESULTS

A significant correlation was found between larger EAT volume and increased LVM, LVEDV, LVESV, LVSV, LVEDD, IVST and corresponding standardized indexes (P < 0.05 for all). Higher EAT density significantly correlated with increased LVM, LVEDV, LVESV, LVSV, LVEDD, IVST, PWT and corresponding standardized indexes (P < 0.05 for all). The largest cardiac structure and function parameters were observed in the population with above-median EAT volume and density.

CONCLUSION

Both large EAT volume and high EAT density were associated with cardiac structure and function in patients with no CAD. The EAT density may render complementary information to EAT volume regarding cardiac geometry changes.

Percutaneous coronary intervention for congenital absence of the right coronary artery with acute myocardial infarction: A case report and literature review

RATIONALE

Congenital absence of the right coronary artery with acute myocardial infarction (AMI) is a rare clinical situation that may lead to death. We report a case of successful percutaneous coronary intervention for congenital absence of the right coronary artery with AMI.

PATIENT CONCERNS

A 53-year-old woman had a 7-day history of chest discomfort that had worsened over 10 hours. She was diagnosed as having myocardial infarction and was admitted to hospital.

DIAGNOSIS

Coronary angiography showed absence of the right coronary artery; the left anterior descending (LAD) branch sent out the right ventricular branch and the posterior descending branch. The LAD branch was occluded and there was diffuse stenosis of the middle right ventricular branch and severe stenosis of the distal circumflex branch.

INTERVENTIONS

Percutaneous coronary intervention was performed. One stent was implanted in the LAD branch and another implanted in the right ventricular branch.

OUTCOMES

The patient was discharged 3 weeks after surgery. The follow-up showed that the patient was asymptomatic without recurrence.

LESSONS

Although absence of the right coronary artery with AMI is a fatal condition, percutaneous coronary intervention remains an effective treatment.

Assessment of Left Ventricular Myocardial Diseases with Cardiac Computed Tomography

Rapid advances in cardiac computed tomography (CT) have enabled the characterization of left ventricular (LV) myocardial diseases based on LV anatomical morphology, function, density, and enhancement pattern. Global LV function and regional wall motion can be evaluated using multi-phasic cine CT images. CT myocardial perfusion imaging facilitates the identification of hemodynamically significant coronary artery disease. CT delayed-enhancement imaging is used to detect myocardial scar in myocardial infarction and to measure the extracellular volume fraction in non-ischemic cardiomyopathy. Multi-energy cardiac CT allows the mapping of iodine distribution in the myocardium. This review summarizes the current techniques of cardiac CT for LV myocardial assessment, highlights the key findings in various myocardial diseases, and presents future applications to complement echocardiography and cardiovascular magnetic resonance.

Role of Cardiac Computed Tomography in the Diagnosis of Left Ventricular Myocardial Diseases

Multimodality imaging is indicated for the evaluation of left ventricular (LV) myocardial diseases. Cardiac magnetic resonance (CMR) allows morphological and functional assessment of the LV along with soft tissue characterization. Technological advances in cardiac computed tomography (CT) have led to the development of techniques for diagnostic acquisition in LV myocardial disease. Cardiac CT facilitates the characterization of LV myocardial disease based on anatomy, function, and enhancement pattern. LV regional and global functional parameters are evaluated using multi-phasic cine CT images. CT myocardial perfusion facilitates the identification of hemodynamically significant coronary artery stenosis. Cardiac CT with delayed enhancement is used to detect myocardial scarring or fibrosis in myocardial infarction and non-ischemic cardiomyopathy, and for the measurement of extracellular volume fraction in non-ischemic cardiomyopathy. In this review, we review imaging techniques and key imaging features of cardiac CT used for the evaluation of myocardial diseases, along with CMR findings.

Age of Data in Contemporary Research Articles Published in Representative General Radiology Journals

Objective

To analyze and compare the age of data in contemporary research articles published in representative general radiology journals.

Materials and Methods

We searched for articles reporting original research studies analyzing patient data that were published in the print issues of the Korean Journal of Radiology (KJR), European Radiology (ER), and Radiology in 2017. Eligible articles were reviewed to extract data collection period (time from first patient recruitment to last patient follow-up) and age of data (time between data collection end and publication). The journals were compared in terms of the proportion of articles reporting the data collection period to the level of calendar month and regarding the age of data.

Results

There were 50, 492, and 254 eligible articles in KJR, ER, and Radiology, respectively. Of these, 44 (88%; 95% confidence interval [CI]: 75.8-94.8%), 359 (73%; 95% CI: 68.9-76.7%), and 211 (83.1%; 95% CI: 78-87.2%) articles, respectively, provided enough details of data collection period, revealing a significant difference between ER and Radiology (p = 0.002). The age of data was significantly greater in KJR (median age: 826 days; range: 299-2843 days) than in ER (median age: 570 days; range: 56-4742 days; p < 0.001) and Radiology (median age: 618; range: 75-4271 days; p < 0.001).

Conclusion

Korean Journal of Radiology did not fall behind ER or Radiology in reporting of data collection period, but showed a significantly greater age of data than ER and Radiology, suggesting that KJR should take measures to improve the timeliness of its data.

Congenital absence of the right coronary artery: A case report and literature review

RATIONALE

Congenital absence of the right coronary artery (RCA) is a rare congenital malformation of the cardiovascular system which may have fatal consequences.

PATIENT CONCERNS

A 63-year-old man with a 5-year history of chest pain after exertion which had aggravated for >1 month was advised for admission and computed tomography angiography (CTA) examination of the coronary artery to screen for coronary artery disease (CAD).

DIAGNOSES

The coronary artery CTA showed absence of RCA arising form the aortic root after which a selective coronary angiography (SCA) examination was done that confirmed the diagnosis of congenital absence of RCA.

INTERVENTIONS

As the patient refused to receive a coronary artery stent implantation citing his financial condition, only symptomatic treatment was given.

OUTCOMES

The patient requested to be discharged from the hospital against the advice of his doctors 1 week later. A query made by the telephone suggested that the patient's symptoms were under control by use of prescribed medications only.

LESSONS

Although being a rare condition, a coronary artery CTA examination can be utilized to screen for congenital absence of RCA and other varieties of cardiovascular malformation whereas SCA can be performed to confirm the diagnosis.