Jacobo Kirsch

Prevalence and significance of incidental extracardiac findings at 64-multidetector coronary CTA

Introduction Computed tomography (CT) angiography of the coronaries has the ability to depict extracardiac lesions in the visualized thorax and upper abdomen. These incidental lesions can often present a challenge to physicians. Methods We performed a retrospective review of 100 consecutive patients referred for 64-multidetector CT coronary CT angiography performed on a 64-slice CT scanner. Two fellowship trained cardiac radiologists reviewed each study by consensus on a CT postprocessing workstation using commercially available software. Extracardiac CT findings (ECF) were classified as benign, indeterminate, or of clinical significance at the time of image evaluation. Benign findings were those considered to be of little clinical significance with no follow-up needed. Indeterminate findings were those deemed of potential clinical importance, requiring correlation of the patient history or a follow-up study. Clinically significant findings were those felt to be of definite clinical importance requiring immediate evaluation or intervention. Results The study cohort consisted of 68 males (68%) and 32 females (32%) with a mean (±standard deviation) age of 63.4±14.5 years and a range of 23 to 87 years. A total of 145 ECF were found in 67 patients (67%), 50 males and 17 females, with a mean age of 68.0±11.8 years and a range of 23 to 87 years. Of those, 107 (73.8%) were considered benign, 22 (15.2%) indeterminate, and 16 clinically significant findings (11.0%). By significance, a total of 107 benign ECF were found in 61 patients, 46 males and 15 females, with a mean age of 67.7±12.2 years and a range of 23 to 87 years. Only 22 ECF indeterminate findings were present, distributed in 21 patients, of which there were 17 males and 5 females, with a mean age of 68.5±13.9 and a range of 23 to 82 years. The 16 clinically significant ECF were distributed in 11 patients, all males, with a mean age of 68.0±8.8 and a range of 55 to 87 years. Conclusions The presence of ECF in our daily practice is frequent, and not limited to the identification of pulmonary nodules, and reinforces the notion that all the organs in the scan should be thoroughly and methodically evaluated.

Detection of myocardial infarction by dual-source coronary computed tomography angiography using quantitated myocardial scintigraphy as the reference standard

Background: Dual-source coronary computed tomography angiography (DS-CTA) has the potential to assess both coronary anatomy and myocardial perfusion. We studied the ability of DS-CTA to detect myocardial infarction (MI) compared to a reference standard of technetium Tc99m sestamibi single photon emission computed tomography (SPECT). Methods: 122 patients with suspected or known coronary artery disease (age 60 (SD 11) years, 36% females) were evaluated by both DS-CTA and SPECT. SPECT-MI size was quantitated using a threshold value of 60% of peak counts on the resting images. MI on DS-CTA was defined as transmural or subendocardial hypoenhancement (<50% of surrounding myocardium), which persisted in both diastolic and systolic reconstructions and was concordant with a coronary artery territory. The performance of DS-CTA to detect SPECT-MI was determined in a blinded, vessel-based analysis. Results: 366 vessel territories were analysed (122 patients ×3). SPECT revealed 20 vessel territories with MI (involving 17 patients). 15/20 (75%) of these vessel territories were also detected by DS-CTA. An additional seven MIs were detected by DS CTA only (considered as false positive). Thus, the sensitivity of DS-CTA for detection of SPECT-MI was 75% (95% CI 56% to 94%), specificity 98% (97% to 100%), positive predictive value 68% (49% to 88%) and negative predictive value 99% (97% to 100%). DS-CTA detected 10/11 (91%) larger MIs (involving >5% of left ventricular (LV) mass by SPECT). For the 15 concordant MIs (in both SPECT and DS-CTA) the mean difference in MI size between modalities was 0.5% (4.6%) of LV mass (95% CI −8.6% to 9.5%). Conclusions: DS-CTA myocardial perfusion imaging showed moderate sensitivity and positive predictive value but high specificity and negative predictive value for detection of SPECT-MI. Most large infarcts (>5% of LV mass) were detected by DS-CTA. When MI was detected by both modalities, there was a good correlation between infarct sizes quantitated by DS-CTA vs SPECT.

Comparison of Magnetic Resonance Imaging Versus Doppler Echocardiography for the Evaluation of Left Ventricular Diastolic Function in Patients With Cardiac Amyloidosis

To assess the role of magnetic resonance imaging (MRI) in the assessment of diastolic function, diastolic mitral inflow parameters using MRI and transthoracic Doppler echocardiography (echocardiography) were compared in patients with cardiac amyloidosis. Thirty-eight patients (age 60 +/- 12 years; 32% women) in sinus rhythm with cardiac amyloidosis (biopsy-proven systemic amyloidosis and positive echocardiographic and contrast-enhanced cardiac MRI findings) were evaluated. Cine phase-contrast MRI images of mitral inflow were obtained in the left ventricle to quantify diastolic blood flow. MRI measurements of diastolic parameters were compared (Spearmans rank correlation) with echocardiographic diastolic mitral inflow velocity parameters. Additional analysis was performed comparing MRI findings in patients with a restrictive echocardiographic diastolic filling pattern (n = 23) versus those without (n = 15). For the 38 patients, early diastolic (E) peak velocity was 61 +/- 26 cm/s using MRI versus 79 +/- 21 using echocardiography (Spearmans rank correlation 0.55, p = 0.0004), and late diastolic (A) peak velocity was 46 +/- 22 cm/s using MRI versus 47 +/- 22 cm/s using echocardiography (Spearmans rank correlation 0.54, p = 0.0005). E/A ratio was 1.55 +/- 0.9 using MRI and 2.25 +/- 1.4 using echocardiography (Spearmans rank correlation 0.75, p <0.0001). Deceleration times in both modalities showed good correlation (MRI, 180 +/- 44 ms vs echocardiography, 179 +/- 49; Spearmans rank correlation 0.61, p = 0.0001). MRI E/A ratio for peak velocities was significantly higher in patients with restrictive echocardiographic patterns (1.95 +/- 1.0) versus those without (0.93 +/- 0.3; p = 0.0003). Two of 23 patients with a restrictive echocardiographic pattern had an MRI E/A ratio <1. In conclusion, mitral inflow peak velocities, deceleration times, and E/A ratios detected using phase-contrast MRI in patients with cardiac amyloidosis showed moderately good correlation with echocardiography and identified most patients with restrictive echocardiographic patterns.

Detection of Myocardial Bridging by 64-Row Computed Tomography Angiography of the Coronaries

Introduction: Myocardial bridging is a congenital condition in which a section of coronary artery is surrounded by myocardium. Historically, myocardial bridging has been diagnosed by catheter angiography. This study investigates the effectiveness of electrocardiogram-gated 64-slice multidetector computed tomography in detecting myocardial bridging. Materials and Methods: We retrospectively reviewed 167 consecutive patients referred for coronary computed tomography angiography between January 4, 2005, and May 24, 2006. We recorded the number of coronary segments exhibiting myocardial bridging and described the location of each according to the American Heart Association classification system. Association of bridging with factors influencing image quality (body mass index and heart rate) was analyzed. Results: Of 152 eligible participants, 49 (32%) showed myocardial bridging. The mid-left anterior descending coronary artery (segment 7) was the most common location accounting for 69% of positive cases. Body mass index and heart rate did not affect detection rates. Conclusion: Electrocardiogram-gated 64-slice multidetector computed tomography is a feasible, noninvasive method of detecting myocardial bridging which may offer higher sensitivity than catheter angiography for this diagnosis.

Magnetic resonance angiography of an ipsilateral double aortic arch due to persistent left fourth and fifth aortic arches.

Persistence of a fifth aortic arch with an ipsilateral fourth arch manifested as a double-lumen aortic arch (DLAA) is a rare congenital anomaly. We present one of the first cases diagnosed by magnetic resonance angiography (MRA) in a 7-year-old girl referred for treatment of subaortic membrane and aortic regurgitation.

Dual-source computed tomographic temporal resolution provides higher image quality than 64-detector temporal resolution at low heart rates.

Objective: To compare coronary image quality at temporal resolutions associated with dual-source computed tomography (DSCT; 83 milliseconds) and 64-detector row scanning (165 milliseconds). Methods: In 30 patients with a heart rate of less than 70 beats per minute, DSCT coronary angiograms were reconstructed at 83- and 165-millisecond temporal resolutions over different cardiac phases. A blinded observer graded coronary quality. Results: The typical DSCT temporal resolution (83 milliseconds) showed a significantly greater quality at end-systole for all coronary vessels and at end-diastole for the right coronary and left anterior descending coronary arteries. For all vessels, the end-diastole produced the highest quality for both temporal resolutions. Conclusions: Imaging at 83 milliseconds creates superior quality at end-systole for all coronary vessels and at end-diastole for the right coronary and left anterior descending coronary arteries. At low heart rates, end-diastole produces the highest quality at both temporal resolutions.

Isolated total anomalous connection of the hepatic veins to the left atrium.

A 63-year-old woman was admitted for management of trial flutter or fibrillation with rapid ventricular response nd hypoxia. For 15 years, she had been treated for preumed idiopathic pulmonary fibrosis with home oxygen and ad known pulmonary hypertension. On admission, oxygen aturation was 82% on supplemental oxygen at 5 L by nasal annula. The prior diagnosis of idiopathic pulmonary fibrois was questioned in the absence of definitive imaging ndings. Other diagnostic options to explain her hypoxia nd pulmonary hypertension were entertained, such as the resence of an intracardiac shunt. A transthoracic echocariogram showed mild left atrial enlargement and pulmonary ypertension, but no evidence of an atrial-level shunt. Atempted transesophageal echocardiogram was unsuccessful ecause of significant oxygen desaturation with minimal edation. An electrocardiographic-gated contrast-enhanced omputed tomography (CT) scan of the chest and upper bdomen was then performed on a 64-row multidetector CT canner (Siemens Sensation 64; Siemens Medical Solutions,