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Charles B Higgins

Publications and source records attributed to Charles B Higgins.

At least 37 records · Page 2Linked to original sources
PubMed2004

Magnetic resonance imaging analysis of right ventricular pressure-volume loops: in vivo validation and clinical application in patients with pulmonary hypertension.

BACKGROUND: The aims of this study were to validate MRI-derived right ventricular (RV) pressure-volume loops for assessment of RV myocardial contractility and then to apply this technique in patients with chronic RV pressure overload for assessment of myocardial contractility, ventricular pump function, and VA coupling. METHODS AND RESULTS: Flow-directed catheters were guided under MR fluoroscopy (1.5 T) into the RV for invasive pressure measurements. Simultaneously, ventricular volumes and myocardial mass were assessed from cine MRI. From sampled data, RV pressure-volume loops were constructed, and maximal ventricular elastance indexed to myocardial mass (E(max_i)) was derived by use of a single-beat estimation method. This MRI method was first validated in vivo (6 swine), with conductance techniques used as reference. Bland-Altman test showed good agreement between methods (E(max_i)=5.1+/-0.5 versus 5.8+/-0.7 mm Hg x mL(-1) x 100 g(-1), respectively; P=0.08). Subsequently, the MRI method was applied in 12 subjects: 6 control subjects and 6 patients with chronic RV pressure overload from pulmonary hypertension. In these patients, indexes of RV pump function (cardiac index), E(max_i), and VA coupling (E(max)/E(a)) were assessed. In patients with pulmonary hypertension, RV pump function was decreased (cardiac index, 2.2+/-0.5 versus 2.9+/-0.4 L x min(-1) x m(-2); P<0.01), myocardial contractility was enhanced (E(max_I), 9.2+/-1.1 versus 5.0+/-0.9 mm Hg x mL(-1) x 100 g(-1); P<0.01), and VA coupling was inefficient (E(max)/E(a), 1.1+/-0.3 versus 1.9+/-0.4; P<0.01) compared with control subjects. CONCLUSIONS: RV myocardial contractility can be determined from MRI-derived pressure-volume loops. Chronic RV pressure overload was associated with reduced RV pump function despite enhanced RV myocardial contractility. The proposed MRI approach is a promising tool to assess RV contractility in the clinical setting.

Adolescent↗
PubMed2004

Acute myocardial infarction: evaluation with first-pass enhancement and delayed enhancement MR imaging compared with 201Tl SPECT imaging.

PURPOSE: To evaluate acute myocardial infarction by using first-pass enhancement (FPE) and delayed enhancement (DE) magnetic resonance (MR) imaging compared with thallium 201 ((201)Tl) single photon emission computed tomography (SPECT). MATERIALS AND METHODS: Contrast material-enhanced FPE MR, inversion-recovery DE MR, and rest-redistribution (201)Tl SPECT images were obtained in 60 consecutive patients (53 men, seven women; mean age [+/- SD], 56 years +/- 13; range, 30-78 years) at 6 days +/- 3 after reperfused first myocardial infarction. Presence of microvascular obstruction was determined on FPE MR images. Infarct size was defined on DE MR images as percentage of left ventricular (LV) area and compared with uptake defect on redistribution (201)Tl SPECT images. Differences in continuous data were analyzed with Student t test. Linear regression and Bland-Altman analysis were used to compare measurements of infarct size. RESULTS: Mean infarct size was not significantly different between DE MR imaging (20.7% +/- 11.5% of LV area) and (201)Tl SPECT (19.4% +/- 14.3% of LV area; P =.26); good correlation (r = 0.73; P <.001) and agreement were found, with a mean difference of +1.3% +/- 9.8% of LV area. (201)Tl SPECT failed to depict infarct in six (20%) of 30 patients with inferior myocardial infarction (mean size, 6.4% +/- 5.7% of LV area on DE MR images), whereas DE MR images showed the infarct in all patients (P <.01). FPE MR images depicted microvascular obstruction in 23 (38%) of 60 patients; these patients had larger infarctions at DE MR imaging than did patients without microvascular obstruction (30.4% +/- 9.0% vs 15.1% +/- 8.4% of LV area, P <.001). (201)Tl SPECT showed larger infarcts in patients with microvascular obstruction (26.7% +/- 16.2% vs 15.0% +/- 11.2% of LV area, P <.01). CONCLUSION: Good correlation and agreement with (201)Tl SPECT indicate DE MR imaging may be used to estimate infarct size 6 days after reperfused acute myocardial infarction. DE MR imaging is more sensitive for detection of inferior infarction than is (201)Tl SPECT. Patients with microvascular obstruction on FPE MR images have larger infarcts.

Adult↗
PubMed2004

MR imaging assessment of cardiac function.

Magnetic resonance (MR) imaging is an accurate and reproducible technique for assessment of ventricular function. Although echocardiography is the mainstay for evaluation of cardiac function, dobutamine stress MR imaging has been shown to be as safe as echocardiography for patients with coronary artery disease and more accurate in patients with suboptimal echocardiographic image quality. This article reviews MR imaging techniques, methods of pharmacologic stress, and clinical applications for assessment of cardiac function, primarily left ventricular function.

Dobutamine↗
PubMed2004

Free-breathing, three-dimensional coronary artery magnetic resonance angiography: comparison of sequences.

PURPOSE: To compare six free-breathing, three-dimensional, magnetization-prepared coronary magnetic resonance angiography (MRA) sequences. MATERIALS AND METHODS: Six bright-blood sequences were evaluated: Cartesian segmented gradient echo (C-SGE), radial SGE (R-SGE), spiral SGE (S-SGE), spiral gradient echo (S-GE), Cartesian steady-state free precession (C-SSFP), and radial SSFP (R-SSFP). The right coronary artery (RCA) was imaged in 10 healthy volunteers using all six sequences in randomized order. Images were evaluated by two observers with respect to signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), visible vessel length, vessel edge sharpness, and vessel diameter. RESULTS: C-SSFP depicted RCA over the longest distance with high vessel sharpness, good SNR, and excellent background suppression. S-GE provided best SNR and CNR in proximal segments, but more vessel blurring and poorer background suppression, resulting in poor visualization of distal segments. R-SSFP images showed good background suppression and best vessel sharpness, but only moderate SNR. C-SGE provided good SNR and reasonable CNR, but lowest vessel sharpness. S-SGE and R-SGE visualized the RCA over the smallest distance, mostly due to vessel blurring and low SNR, respectively. CONCLUSION: Overall, Cartesian SSFP provided the best image quality with excellent vessel sharpness, visualization of long vessel segments, and good SNR and CNR.

Adult↗
PubMed2004

Accentuation of high susceptibility of hypertrophied myocardium to ischemia: complementary assessment of Gadophrin-enhancement and left ventricular function with MRI.

The aim of the study was to compare infarction size and left ventricular (LV) function in normal and hypertrophied hearts after brief ischemia using Gadophrin-enhancement and functional assessment by MRI. Rats (n = 20) were assigned to aortic banding to induce LV hypertrophy or control. Eight weeks later, rats were subjected to 25 min of regional myocardial ischemia followed by 3 hr of reperfusion. The necrosis-specific agent Gadophrin-3 was injected to delineate infarcted myocardium on MRI. Effects of aortic banding and ischemia on LV mass and function were determined. At postmortem, areas at risk and infarction were measured. Close correlation was found between LV mass measured with MRI and at postmortem (r = 0.98). LV mass measured with MRI was significantly greater (0.81 +/- 0.02 g) in animals with aortic banding compared to control (0.62 +/- 0.02 g; P < 0.001). Infarction size was larger in hypertrophied hearts (19.0 +/- 1.4% / 18.3 +/- 1.5%) than in control (9.8 +/- 1.7% / 9.2 +/- 2.0%) on Gadophrin-enhanced MRI and at postmortem, respectively. Similarly, greater impairment in ejection fraction was observed in hypertrophied hearts with MRI (39 +/- 4% vs. 49 +/- 2%; P = 0.02). Gadophrin-3 provides accurate estimation of infarct size in hypertrophied hearts. Hypertrophied hearts are more sensitive to ischemia than nonhypertrophied hearts. The complementary assessment of Gadophrin-enhancement and LV function with MRI provides unique information about myocardium sensitivity to ischemia.

Animals↗
PubMed2004

Comparison of late enhancement cardiovascular magnetic resonance and thallium SPECT in patients with coronary disease and left ventricular dysfunction.

PURPOSE: Late enhancement magnetic resonance imaging (MRI) was compared with thallium-201 rest-redistribution single photon emission computed tomography (SPECT) in patients with reduced left ventricular (LV) function and prior myocardial infarction (MI). BACKGROUND: Hyperenhancement on contrast cardiac MRI using gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA) has been reported to identify nonviable myocardium. Comparisons of MRI and thallium-201 SPECT have recently been reported. This study focuses on the comparison of these modalities specifically in patients with ischemic heart failure, where viability determination is most clinically relevant. METHODS: Fifteen patients with LV dysfunction and prior MI [mean ejection fraction (EF) 35 +/- 11%] underwent thallium-201 rest-redistribution scintigraphy and contrast MRI on separate days. Each short axis slice was divided into six 60-degree segments, and correlations between MRI and scintigraphy were made on viability detection for each segment. For SPECT, the mean uptake score was calculated from the average of all percent relative activity values throughout each segment. Areas with < 50% of maximal thallium uptake were considered nonviable. On MRI, regions with increased signal intensity after an injection of 0.1 mmol/kg Gd-DPTA were considered nonviable. RESULTS: A total of 558 segments were analyzed. Overall, there was a strong inverse relationship between the area of hyperenhancement on MRI and diminished thallium-201 uptake on SPECT (r = -0.51, P < 0.001). There was a significant correlation between the imaging methods for each individual segment, except for the inferior-septal segment (r = -0.38, P < 0.08). CONCLUSIONS: In patients with LV dysfunction and prior MI, our data suggest MRI hyperenhancement significantly correlates with myocardial nonviability by thallium-201 SPECT. Correlations were weaker in the inferior-septal region, which may be due to SPECT attenuation artifact.

Contrast Media↗
PubMed2004

Magnetic resonance imaging in myocardial ischemia.

PURPOSE OF REVIEW: MRI is a novel strategy to assess myocardial ischemia. It provides information on myocardial perfusion, viability, and potentially the extent of coronary artery disease. This technology may replace many of the current noninvasive and, perhaps, invasive techniques in the diagnosis and management of patients with coronary artery disease. This review aims to cover the major advances in cardiac MRI related to both diagnosis and therapy of myocardial ischemia. RECENT FINDINGS: Although improved image acquisition techniques have made it possible to obtain excellent image quality in most patients, powerful processing software has permitted the quantification of accurate and reproducible functional information regarding perfusion, wall motion, and viability. Stem cell delivery and gene therapy to the myocardium using cardiac MRI has been shown to be feasible. The use of 3-T systems for cardiac imaging and the imaging of atherosclerosis with MRI are currently being studied. SUMMARY: MRI is a highly accurate method of characterizing both reversible and irreversible myocardial injury and of obtaining information on myocardial viability. It has the ability to prognostic patients by evaluating ejection fraction and contractility. Robust and uncomplicated methodologies for coronary MR angiography are almost on the horizon. Quantification of several parameters used to diagnose, prognosticate, and follow patients with ischemic heart disease should be much easier in the future. It may, with the recent advances in imaging such as 3-T systems, provide major noninvasive diagnostic capability. Cardiac MRI, with its improved imaging, and its ability to treat and monitor various forms of invasive and noninvasive therapy, may attain its potential as a "one-stop shop" in the near future.

Coronary Angiography↗
PubMed2004

Contrast-enhanced MR delineation of stunned myocardium with administration of MnCl(2) in rats.

PURPOSE: To determine whether stunned myocardium can be delineated at magnetic resonance (MR) imaging with differential cellular uptake of manganese ions. MATERIALS AND METHODS: Twenty-one adult Sprague-Dawley rats underwent either (a) a sequence of three episodes of 10 minutes of coronary artery occlusion and 12 minutes of reflow (group 1, n = 9); (b) a single episode of 10 minutes of occlusion followed by reflow (group 2, n = 6), designed to produce different degrees of myocardial stunning; or (c) a single episode of 2 minutes of occlusion followed by reperfusion (group 3, n = 6), designed to produce no stunning. Ventricular wall thickening was measured on spin-echo (SE) MR images. MnCl2 (0.025 mmol/kg) was intravenously infused for 10 minutes. Highly T1-sensitive inversion-recovery (IR) SE images were obtained to detect subtle regional differences in manganese accumulation. Hearts were stained at sacrifice to define area at risk and to test for myocardial infarction. Significance of differences in mean values was evaluated with repeated-measures analysis of variance. RESULTS: All hearts were free of infarction, as detected with triphenyltetrazolium chloride staining. On IR SE images, the hearts from rats in groups 1 and 2 exhibited clearly delineated regions of diminished manganese uptake in the expected territory of the occluded artery. The circumferential extent of the manganese-defined defect (45.5% +/- 5.6) was similar to that of the area at risk (46.8% +/- 7.5). Systolic wall thickening in the defect was significantly (P <.01) less than in the nonischemic myocardium (2.7% +/- 3.3 vs 31.2% +/- 7.5 and 10.0% +/- 4.8 vs 28.6% +/- 6.5, respectively, for groups 1 and 2). The hearts from rats in group 3 demonstrated no wall thickening deficit or abnormal zone on manganese-enhanced images. CONCLUSION: Stunned myocardium was delineated with MnCl2-enhanced MR imaging as a hypoenhanced zone. This finding suggests that Ca2+ channel activity is diminished in stunned myocardium.

Animals↗
PubMed2004

Transendocardial delivery of extracellular myocardial markers by using combination X-ray/MR fluoroscopic guidance: feasibility study in dogs.

PURPOSE: To demonstrate the feasibility of using a combination of x-ray fluoroscopic and magnetic resonance (MR) fluoroscopic (ie, x-ray/MR fluoroscopy) guidance for left ventricular (LV) catheterization and transendocardial delivery of extracellular tissue markers. MATERIALS AND METHODS: Experiments were performed in six dogs by using an x-ray/MR fluoroscopy system. The arterial guide wire and catheter were advanced into the heart with x-ray fluoroscopic guidance. The dogs were injected with 0.5, 1.0, and 2.0 mL of iohexol. For passive catheter tracking, a steady-state free precession MR imaging sequence was used. A steerable dual-lumen catheter was used to transendocardially inject a mixture of gadodiamide (0.05 mol/L) plus Evans blue dye (3%). An electrocardiographically gated dual-inversion-recovery MR imaging sequence was used to visualize the myocardial delivery of the gadodiamide-blue dye mixture. A high concentration of gadodiamide (0.5 mol/L) was used to demarcate the borders of the area of interest, or "hit the target." Blood pressure, heart rate, and oxygen saturation were measured before and after the intervention. Analysis of variance, Scheffé, and paired Student t tests were used for data analysis. RESULTS: LV catheterization via arterial access was feasible with two-dimensional x-ray fluoroscopic and three-dimensional MR fluoroscopic guidance. Delivery of the gadodiamide-blue dye mixture and the consequences of the procedure were monitored with MR imaging. Gadolinium-enhanced regions were bright on T1-weighted MR images, but they varied in size as a function of injectant volume. The mean sizes of these regions were 1.5% +/- 0.6 of the LV after the 0.5-mL injection of the mixture and 7.0% +/- 0.5 of the LV after the 2.0-mL injection (P <.001, Scheffé test). The corresponding mean sizes of the blue dye-enhanced regions were 2.3% +/- 0.6 and 8.3% +/- 0.4, respectively (P <.001). A high concentration of gadodiamide caused signal intensity loss around the gadolinium-enhanced regions. CONCLUSION: Transendocardial delivery of potential therapeutic solutions is feasible with x-ray/MR fluoroscopic guidance. The injection catheter can be navigated with MR imaging guidance to hit the target.

Animals↗
PubMed2004

Effect of potassium-channel opener therapy on reperfused infarction in hypertrophied hearts: demonstration of preconditioning by using functional and contrast-enhanced magnetic resonance imaging.

Effects of therapy with the potassium-channel opener and vasodilator nicorandil were studied in reperfused infarction of hypertrophied hearts by using magnetic resonance imaging (MRI), hemodynamic measurements, and histochemical staining. Aortic banding was performed on 22 Sprague-Dawley rats to induce left ventricular (LV) hypertrophy; 11 were the controls. Eight weeks later, the left coronary artery was occluded for 25 minutes in all 33 animals, followed by 3 hours of reperfusion. During occlusion, 11 rats with LV hypertrophy received nicorandil (0.1 mg/kg bolus and 1.5 mg/kg/h for 3 hours). The new necrosis-specific contrast agent Gadophrin-3 was administered to all animals to delineate infarction on multislice T1-weighted spin-echo MRI. Nicorandil increased ischemic tolerance of LV hypertrophy as shown by the reduction of infarction size from 19.3% +/- 1.3% to 10.0% +/- 2.5% LV (P = .005). Infarction size in treated animals was identical to control (9.3% +/- 1.6%). Close correlation was found between MRI and postmortem findings. Functional MRI revealed an improvement in ejection fraction in nicorandil-treated hearts (48.5% +/- 3.4% vs 38.1% +/- 3.2%, P = .04). LV end-diastolic volume and pressure, aortic pressure, and peripheral vascular resistance were highest in untreated hypertrophied hearts. Brief ischemia caused severe injury in hypertrophied hearts. Infusing nicorandil increased the tolerance of hypertrophied hearts to ischemia. MRI is a suitable technique for the evaluation of new therapies in LV hypertrophy.

Animals↗
PubMed2003

Distribution of intramyocardially injected extracellular MR contrast medium: effects of concentration and volume.

The purpose of this study was to assess the potential of intramyocardially injected Gd-DTPA solution as a marker for distribution of intramyocardially delivered therapeutic solutions. The effects of concentration and volume of the extracellular MR contrast medium Gd-DTPA on signal intensity and spatial extent of enhancement was determined after intramyocardial delivery. In anesthetized pigs (n=11), mixtures of Gd-DTPA (0.15, 0.1 and 0.05 mmol/ml) and Evan's blue tissue dye (3%) were injected into the wall of the left ventricle. In each pig 1 ml of 0.15 mmol/ml, 2 ml of 0.1 ml and 3 ml of 0.05 mmol/ml Gd-DTPA were injected remote from each other. Arterial blood pressure, heart rate and ECG were monitored throughout the procedure. Five minutes after injections were performed, the pigs were killed and the hearts excised. T1-weighted spin-echo MR images were acquired to measure regional signal intensity (SI) and extent of the enhanced regions. The hearts were sliced and mass of blue stained regions was determined and compared with mass of enhanced areas on MRI. Gd-DTPA significantly (p<0.001) increased regional SI compared with remote myocardium in a concentration dependent fashion (109 +/- 4% at 0.05 mmol/ml, 202 +/- 7% at 0.1, and 327 +/- 6% at 0.15) while the mass of enhanced region was 0.6 +/- 0.1 g after injection of 1 ml, 1.4 +/- 0.2 g after 2 ml and 2.3 +/- 0.3 g after 3 ml (p<0.001). Regression and Bland-Altman analysis revealed that there was close correlation and agreement between MRI and histomorphometry (r=0.98, p<0.001). Magnitude and spatial extent of enhancement depend on concentration and volume of injected contrast medium. Intramyocardial injection of extracellular MR contrast media may be useful as a marker for the extent of distribution of intramyocardially delivered therapeutic solutions.

Animals↗
PubMed2003

Effects of pulmonary insufficiency on biventricular function in the developing heart of growing swine.

BACKGROUND: This study was conducted to determine the effects of chronic pulmonary insufficiency (PI) on right (RV) and left (LV) ventricular function in young growing swine. METHODS AND RESULTS: Six PI and 5 control animals were studied. PI was induced by transcatheter placement of stents across the pulmonary valve. Indices of systolic function (ejection fraction, cardiac output, and cardiac functional reserve), diastolic function (compliance), and myocardial contractility (the slope of the relationship of end-systolic pressure versus end-systolic volume [Emax] and the slope of the dP/dtmax-end-diastolic volume relationship [MdP/dt]) were assessed within 2 days of intervention and 3 months later. MRI was used to quantify PI and ventricular volumes. Conductance catheter techniques were used to obtain indices of contractility and diastolic compliance from pressure-volume relations at rest and under dobutamine infusion. In the PI group, pulmonary regurgitant fraction was 49.2+/-5.9% at 3-month follow-up. RV cardiac functional reserve was limited, diastolic function was preserved, and myocardial contractility was altered (Emax=2.6+/-0.3 mm Hg/mL for the PI group versus 3.5+/-0.4 mm Hg/mL for control; P<0.01). LV cardiac functional reserve was limited, ventricular compliance decreased, and myocardial contractility was preserved. CONCLUSIONS: In the young developing heart, chronic PI alters biventricular systolic function, RV myocardial contractility, and LV diastolic performance.

Animals↗
PubMed2003

Magnetic resonance--guided cardiac catheterization in a swine model of atrial septal defect.

BACKGROUND: Radiation exposure during cardiac catheterization, limited image planes, and poor soft tissue definition are disadvantages of x-ray fluoroscopy that could be overcome with the use of MRI. This study evaluates the feasibility of real-time MRI (MR fluoroscopy) to guide left and right heart catheterization. METHODS AND RESULTS: Anesthetized pigs (n=7) with defects of the atrial septum were catheterized using venous and arterial access. A prototype active tracking catheter was used to obtain blood pressures and samples from cardiac chambers and great vessels using antegrade, transseptal, and retrograde approaches. MR fluoroscopy was used for catheter steering. Velocity-encoded cine MRI was used to measure pulmonary and aortic blood flow to calculate vascular resistances. Image planes used during catheter manipulation used rapid sequencing to planes directed by the operator to include the tip of the catheter and the chamber to be entered. All areas of interest were effectively entered, and samples were obtained. In the presence of an acute atrial septal defect, a Qp/Qs ratio of 1.3+/-0.2 was measured, and no significant differences in pressure between inferior vena cava, right atrium, and left atrium were found. Pulmonary and aortic flow were 4.9+/-0.6 and 3.7+/-0.4 L/min, and pulmonary and systemic vascular resistance were 312+/-134 and 2006+/-336 dyne x s x cm(-5). CONCLUSIONS: Left and right heart catheterization using MR guidance is feasible. The combination of hemodynamic catheterization data with anatomic and functional MRI may significantly improve the evaluation of patients with congenital heart disease while avoiding radiation exposure.

Animals↗
PubMed2003

MR findings of collateral circulation are more accurate measures of hemodynamic significance than arm-leg blood pressure gradient after repair of coarctation of the aorta.

PURPOSE: To determine the relationship between percent stenosis and three indicators of hemodynamic significance-arm-leg blood pressure gradient, direct visualization of collaterals, and percent increase flow from proximal to distal descending thoracic aorta-in patients with prior repair of coarctation of the aorta (CoA). MATERIALS AND METHODS: Magnetic resonance imaging (MRI) examinations of 19 patients with prior repair of CoA were retrospectively reviewed. Percent stenosis was compared to the arm-leg blood pressure gradient as obtained from chart review, the depiction of collaterals by gadolinium-enhanced magnetic resonance angiography (MRA), and the percent increased flow in the distal thoracic aorta as measured by velocity-encoded cine MRI. Some imaging series or blood-pressure values were not available in some patients. All of the data were available for 15 of the 19 patients. RESULTS: The arm-leg blood pressure gradient showed no statistical association with percent stenosis (R(2) = 0.10, P = 0.22), direct visualization of collaterals (P = 0.80), or percent increase in flow (R(2) < 0.01, P = 0.85). Percent stenosis did show association with visualization of collaterals (P = 0.01) and increase flow (R(2) = 0.62, P < 0.01). CONCLUSION: The arm-leg blood pressure gradient is not a reliable indicator of hemodynamic significance of restenosis in patients with prior repair of CoA. Direct visualization of collateral vessels by MRA and percent increase in flow from proximal to distal descending thoracic aorta are reliable indicators of hemodynamic significance.

Adult↗
PubMed2003

Whole-heart steady-state free precession coronary artery magnetic resonance angiography.

Current implementations of coronary artery magnetic resonance angiography (MRA) suffer from limited coverage of the coronary arterial system. Whole-heart coronary MRA was implemented based on a free-breathing steady-state free-precession (SSFP) technique with magnetization preparation. The technique was compared to a similar implementation of conventional, thin-slab coronary MRA in 12 normal volunteers. Three thin-slab volumes were prescribed: 1) a transverse slab, covering the left main (LM) artery and proximal segments of the left anterior ascending (LAD) and left circumflex (LCX) coronary arteries; 2) a double-oblique slab covering the right coronary artery (RCA); and 3) a double-oblique slab covering the proximal and distal segments of the LCX. The whole-heart data set was reformatted in identical orientations. Visible vessel length, vessel sharpness, and vessel diameter were determined and compared separately for each vessel. Whole-heart coronary MRA visualized LM/LAD (11.7 +/- 3.4 cm) and LCX (6.9 +/- 3.6 cm) over a significantly longer distance than the transverse volume (LM/LAD, 6.1 +/- 1.1 cm, P < 0.001; LCX, 4.2 +/- 1.2 cm, P < 0.05). Improvements in visible vessel length for RCA and LCX in the whole-heart approach vs. their respective targeted volumes were not significant. It is concluded that the whole-heart coronary MRA technique improves visible vessel length and facilitates high-quality coronary MRA of the complete coronary artery tree in a single measurement.

Adult↗