Cardiovascular Computed Tomographic Angiography Research Articles

Cardiovascular Computed Tomographic Angiography as a Virtual Patient Avatar for Individualized Surgical Planning of Complex Anomalous Coronary Artery Anatomy.

Cardiovascular computed tomographic angiography (CCTA) 3-D thoracic reconstruction can serve as a "virtual patient avatar" providing surgical views for approach to complex anomalous coronary artery anatomy. Images demonstrated a single coronary artery ostium arising from the right aortic sinus with trifurcation into a prepulmonic left anterior descending coronary artery (LAD), an interarterial circumflex with a subsequent intraseptal course, and normal course of the right coronary artery. Virtual 3-D CCTA reconstructions were important to planning an incisional plane for surgical correction.

INVITED REVIEW—COMPUTED TOMOGRAPHIC ANGIOGRAPHY (CTA) OF THE THORACIC CARDIOVASCULAR SYSTEM IN COMPANION ANIMALS

Computed tomographic angiography (CTA) of the thoracic cardiovascular system is offering new diagnostic opportunities in companion animal patients with the increasing availability of multidetector-row computed tomographic (MDCT) units in veterinary facilities. Optimal investigation of the systemic, pulmonary, and coronary circulation provides unique challenges due to the constant movement of the heart, the small size of several of the structures of interest, and the dependence of angiographic quality on various contrast bolus design and patient factors. Technical and practical aspects of thoracic cardiovascular CTA are reviewed in light of the currently available veterinary literature and future opportunities given utilizing MDCT in companion animal patients with suspected thoracic cardiovascular disease.

Anomalous Coronary Arteries

Cardiovascular computed tomographic angiography (CCTA) provides an understanding of the three-dimensional (3D) coronary artery anatomy in relation to cardiovascular thoracic structures important to the surgical management of anomalous coronary arteries (ACAs). Although some ACA variants are not clinically significant, others can lead to ischemia/infarction, related acute ventricular dysfunction, ventricular arrhythmias, and sudden cardiac death. The CCTA is important to surgical decision making, as it provides noninvasive visualization of the coronary arteries with (1) assessment of origin, course, and termination of coronary artery anomalies in the context of 3D thoracic anatomy, (2) characterization of anatomy helpful for differentiation of benign versus hemodynamically significant variants, (3) identification of other cardiothoracic anomalies, and (4) detection of coronary artery disease. High-risk ACA anatomy in the appropriate clinical setting can require surgical intervention with decisions including minimally invasive versus open sternotomy approach, correction via reimplantation of a coronary artery, alteration of the ACA course without reimplantation, or bypass of an ACA. Given the rarity of ACA, there is limited data in the literature, and significant controversy related to the management issues. The management of ACA requires comprehensive clinical history, thorough assessment of cardiac function, and detailed anatomic imaging. Future studies will need to address the long-term outcome based on detailed assessment of original anatomy and surgical approach.

Unoperated Congenitally Corrected Transposition of the Great Arteries, Nonrestrictive Ventricular Septal Defect, and Pulmonary Stenosis in Middle Adulthood

Submitted May 6, 2011; Accepted August 3, 2011. The survival into adulthood of patients with unoperated complex congenital heart disease with anomalies often considered life threatening in infancy and childhood requires a complex interplay of "balanced" defects allowing for cardiovascular physiology compatible with long-term survival. We report on a series of three cases from our advanced imaging database of middle-aged adults presenting with multiple similar defects providing a hemodynamically balanced circulation. The constellation of defects seen in each of these patients included congenitally corrected transposition of the great arteries, a large nonrestrictive ventricular septal defect, valvular pulmonary stenosis, and in two cases anomalous coronary arteries. Cardiovascular computed tomographic angiography (CCTA) and cardiovascular magnetic resonance imaging (CMR) were important to the characterization of the multiple defects and their three-dimensional relationships in these cases. Treatment decisions in patients with this constellation of findings are challenging, given the limited data due to the rarity of survival of patients with these defects into middle adulthood and the paucity of data related to decisions and approaches to medical management, surgical correction, or transplantation.

Prospective Randomized Trial of Venous Cardiac Computed Tomographic Angiography for Facilitation of Cardiac Resynchronization Therapy

Cardiovascular computed tomographic angiography (CTA) can visualize the coronary veins. We sought to assess the ability of CTA to facilitate resynchronization therapy (CRT) procedures using a prospective randomized single-center pilot study. Patients underwent CTA for characterization of cardiomyopathy prior to biventricular implantable cardiac-defibrillator implant. Randomization was performed with operator review of the CTA for coronary venous anatomy prior to CRT in one-half of the cases. Invasive coronary venous angiograms were used in all procedures. Analysis included procedure times and utilization of contrast, fluoroscopy, and guide catheters. Characteristics of the 26 patients enrolled were mean age 55 ± 11 years, male 76.9%, ischemic etiology 35%, ejection fraction 25 ± 3%, class III congestive heart failure 100%, and QRS duration 179 ± 29 ms. Of patients enrolled, 22 had both CTA and procedure initiation. Three patients (two with CTA review and one without CTA review) had aborted procedures due to hemodynamic issues. Analysis of the 22 patients (nine with preprocedure CTA review and 13 without CTA review) demonstrated that preprocedure review of CTA coronary venous anatomy led to significantly decreased procedure times and utilization of contrast, fluoroscopy, and guide catheters. Preprocedure review of CTA coronary venous anatomy may lead to decreased procedural times and utilization of contrast, fluoroscopy, and guide catheters. These preliminary results will need to be evaluated in larger heart failure populations undergoing CRT.

Aortic coarctation by cardiovascular CT angiography

The patient is a 12-year-old boy who underwent prospectively gated step-and-shoot chest CT (computed tomographic) angiography with a 64-multislice CT scanner (64-MSCT) for a preliminary diagnosis of coarctation of aorta. The data was acquired in a manner to significantly minimize radiation to the patient, including use of 80 kVp (rather than 120 kVp, much more commonly employed in cardiac CT), low mA (120 mA, rather than typical 400 mA), and prospective acquisition using a VCT 64 detector scanner (General Electric, Milwaukee, WI) (Figs. 1 and 2). Total radiation dose was 0.9 mSv, despite imaging from sternal notch to liver. Findings included dilated ascending aorta (43 mm diameter) and a total coarctation of descending aorta with very well-developed collaterals. The left internal mammary artery and right internal mammary artery were noted to be very large (7 mm diameter).

Abstract 3414: Mortality Incidence and the Severity of Coronary Atherosclerosis Assessed by CT Angiography

Objectives: This study was performed to investigate the relationship between the degree of coronary artery disease (CAD) and incidence of mortality in patients who were referred for Cardiovascular Computed Tomographic Angiography (CTA) in an outpatient setting. Background: Non invasive coronary angiography is being increasingly performed by CTA to assess for significant obstructive CAD. While there is extensive literature on mortality incidence with respect to degree of CAD defined by conventional coronary angiography and coronary artery calcification, no such outcome data exists for coronary CTA. Methods: We observed over a mean follow-up of 5±2 yrs, 2971 consecutive patients who underwent cardiac CTA. Significant CAD, defined as greater or equal to 50% luminal narrowing of an epicardial vessel, was determined by CTA. All cause mortality was detected through a search of the national death registry by patient’s social security number. Multivariable Cox proportional hazards models were developed to predict all-cause mortality. Results: Among this cohort, we detected a total of 102 deaths (3.4%). We observed the following mortality rates among patients with varying degrees of atherosclerotic disease burden; 3 vessel disease 18.8% (3/16), 2 vessel disease 6.1% (6/99), 1 vessel disease 3.5% (12/347), non obstructive disease 2.1% (22/1062), no detectable disease 1.8% (15/849). Patients with increasing severity of both non-obstructive and obstructive disease were more likely to die over the subsequent 5 years (Table 1 ). Conclusions: The severity of coronary artery disease assessed by noninvasive CT angiography independently correlates with all cause mortality.