Ludovico La Grutta

Prevalence of anatomical variants and coronary anomalies in 543 consecutive patients studied with 64-slice CT coronary angiography

The aim of our study was to assess the prevalence of variants and anomalies of the coronary artery tree in patients who underwent 64-slice computed tomography coronary angiography (CT-CA) for suspected or known coronary artery disease. A total of 543 patients (389 male, mean age 60.5u2009±u200910.9) were reviewed for coronary artery variants and anomalies including post-processing tools. The majority of segments were identified according to the American Heart Association scheme. The coronary dominance pattern results were: right, 86.6%; left, 9.2%; balanced, 4.2%. The left main coronary artery had a mean length of 112u2009±u200955xa0mm. The intermediate branch was present in the 21.9%. A variable number of diagonals (one, 25%; two, 49.7%; more than two, 24%; none, 1.3%) and marginals (one, 35.2%; two, 46.2%; more than two, 18%; none, 0.6%) was visualized. Furthermore, CT-CA may visualize smaller branches such as the conus branch artery (98%), the sinus node artery (91.6%), and the septal branches (93%). Single or associated coronary anomalies occurred in 18.4% of the patients, with the following distribution: 43 anomalies of origin and course, 68 intrinsic anomalies (59 myocardial bridging, nine aneurisms), three fistulas. In conclusion, 64-slice CT-CA provides optimal visualization of the variable and complex anatomy of coronary arteries because of the improved isotropic spatial resolution and flexible post-processing tool.

Influence of convolution filtering on coronary plaque attenuation values: observations in an ex vivo model of multislice computed tomography coronary angiography

Attenuation variability (measured in Hounsfield Units, HU) of human coronary plaques using multislice computed tomography (MSCT) was evaluated in an ex vivo model with increasing convolution kernels. MSCT was performed in seven ex vivo left coronary arteries sunk into oil followingthe instillation of saline (1/∞) and a 1/50 solution of contrast material (400xa0mgI/ml iomeprol). Scan parameters were: slices/collimation, 16/0.75xa0mm; rotation time, 375xa0ms. Four convolution kernels were used: b30f-smooth, b36f-medium smooth, b46f-medium and b60f-sharp. An experienced radiologist scored for the presence of plaques and measured the attenuation in lumen, calcified and noncalcified plaques and the surrounding oil. The results were compared by the ANOVA test and correlated with Pearson’s test. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. The mean attenuation values were significantly different between the four filters (pu2009<u20090.0001) in each structure with both solutions. After clustering for the filter, all of the noncalcified plaque values (20.8u2009±u200939.1, 14.2u2009±u200935.8, 14.0u2009±u200932.0, 3.2u2009±u200932.4 HU with saline; 74.7u2009±u200966.6, 68.2u2009±u200963.3, 66.3u2009±u200966.5, 48.5u2009±u200960.0 HU in contrast solution) were significantly different, with the exception of the pair b36f–b46f, for which a moderate-high correlation was generally found. Improved SNRs and CNRs were achieved by b30f and b46f. The use of different convolution filters significantly modifief the attenuation values, while sharper filtering increased the calcified plaque attenuation and reduced the noncalcified plaque attenuation.

Reproducible coronary plaque quantification by multislice computed tomography

Background: The aim of this study was to investigate reproducibility and accuracy of computer‐assisted coronary plaque measurements by multislice computed tomography coronary angiography (QMSCT‐CA). Methods and Results: Forty‐eight patients undergoing MSCT‐CA and coronary arteriography for symptomatic coronary artery disease and quantitative intravascular ultrasound (IVUS, QCU) were examined. Two investigators performed the QMSCT‐CA twice and a third investigator performed the QCU, all blinded for each others results. There was no difference found for the matched region of interest (ROI) lengths (QCU 29.4 ± 13 mm vs. QMSCT‐CA 29.6 ± 13 mm, P = 0.6; total length = 1,400 mm). The comparison of volumetric measurements showed (lumen QCU 267 ± 139 mm3 vs. mean QMSCT‐CA 177 ± 91 mm3, P << 0.001; vessel 454 ± 194 mm3 vs. 398 ± 187 mm3, P << 0.001; and plaque 189 ± 93 mm3 vs. 222 ± 121 mm3; investigator 1, P = 0.02; and investigator 2, P = 0.07) significant differences. Automated lumen detection was also applied for QMSCT‐CA (218 ± 112 mm3, P << 0.001 vs. QCU). The interinvestigator variability measurements for QMSCT‐CA showed no significant differences. Conclusion: QMSCT‐CA systematically underestimates absolute coronary lumen‐ and vessel dimensions when compared with QCU. However, repeated measurements of coronary plaque by QMSCT‐CA showed no statistically significant differences, although, the outcome showed a scattered result. Automated lumen detection for QMSCT‐CA showed improved results when compared with those of human investigators.

Computed tomography coronary angiography vs. stress ECG in patients with stable angina

PurposeThis study compared the role of multislice computed tomography coronary angiography (MSCT-CA) and stress electrocardiography (ECG) in the diagnostic workup of patients with chronic chest pain.Materials and methodsMSCT-CA was performed in 43 patients (31 men, 12 women, mean age 58.8±7.7 years) with stable angina after a routine diagnostic workup involving stress ECG and conventional CA. The following inclusion criteria were adopted: sinus rhythm and ability to hold breath for 12 s. Beta-blockers were administered in patients with heart rate ≥70 beats/minute. In order to identify or exclude patients with significant stenoses (≥50% lumen), we determined posttest likelihood ratios of stress test and MSCT-CA separately and of MSCT-CA performed after the stress test.ResultsThe pretest probability of significant coronary artery disease (CAD) was 74%. Positive and negative likelihood ratios were 2.3 [95% confidence interval (CI) 1.0–5.3] and 0.3 (95% CI: 0.2–0.7) for the stress test and 10.0 (95% CI: 1.8–78.4) and 0.0 (95% CI: 0.0-∞) for MSCT-CA, respectively. MSCT-CA increased the posttest probability of significant CAD after a negative stress test from 50% to 86% and after a positive stress test from 88% to 100%. MSCT-CA correctly detected all patients without CAD.ConclusionsNoninvasive MSCT-CA is a potentially useful tool in the diagnostic workup of patients with stable angina owing to its capability to detect or exclude significant CAD.RiassuntoObiettivoConfrontare il ruolo dell’angiografia coronarica mediante tomografia computerizzata multistrato (ACTCMS) e della prova da sforzo con ECG nell’iter diagnostico dei pazienti con angina stabile.Materiali e metodiL’AC-TCMS è stata eseguita in 43 pazienti (31 uomini, 12 donne, età media 58,8±7,7 anni) con angina stabile sottoposti ad iter diagnostico comprendente la prova da sforzo con ECG e l’angiografia coronarica convenzionale. Sono stati rispettati i seguenti criteri d’inclusione: ritmo cardiaco sinusale, capacità di mantenere l’apnea inspiratoria per almeno 12 secondi. Si è ricorso alla somministrazione di β-bloccanti nei pazienti con ritmo ≥70 bpm/minuto. Allo scopo di identificare o escludere i pazienti con stenosi significative (lume ≥50%) sono stati determinati i rapporti di verosimiglianza post-test della prova da sforzo e dell’AC-TCMS indipendentemente, e dell’AC-TCMS eseguita dopo il test da sforzo.RisultatiLa probabilità pre-test di una significativa coronaropatia aterosclerotica (CA) è risultata del 74%. I rapporti di verosimiglianza positivo e negativo sono risultati rispettivamente 2,3 (95% IC: 1,0–5,3) e 0,3 (95% IC: 0,2–0,7) per il test da sforzo, 10,0 (95% IC: 1,8–78,4) e 0,0 (95% IC: 0,0-∞) per l’AC-TCMS. L’AC-TCMS ha migliorato la probabilità post-test di una rilevante CA dal 50% fino all’86% dopo una prova da sforzo negativa, e dall’88% fino al 100% dopo una prova da sforzo positiva; l’AC-TCMS ha correttamente identificato tutti i pazienti senza CA.ConclusioniL’AC-TCMS é uno strumento non invasivo potenzialmente utile nell’iter diagnostico dei pazienti con angina stabile in grado di rendere nota od escludere una significativa CA.

Imaging techniques for the vulnerable coronary plaque.

The goal of this article is to illustrate the main invasive and noninvasive diagnostic modalities to image the vulnerable coronary plaque, which is responsible for acute coronary syndrome. The main epidemiologic and histological issues are briefly discussed in order to provide an adequate background. Comprehensive coronary atherosclerosis imaging should involve visualization of the entire coronary artery tree and plaque characterization, including three-dimensional morphology, relationship with the lumen, composition, vascular remodelling and presence of inflammation. No single technique provides such a comprehensive description, and no available modality extensively identifies the vulnerable plaque. In particular, we describe multislice computed tomography, which at present seems to be the most promising noninvasive tool for an exhaustive image-based quantification of coronary atherosclerosis.RiassuntoCon questo articolo si vogliono illustrare le principali metodiche di imaging invasivo e non invasivo, che si prefiggono di identificare la placca vulnerabile coronarica, responsabile delle sindromi coronariche acute. Sono stati brevemente analizzati gli aspetti epidemiologici ed anatomo-patologici di maggiore rilievo allo scopo di fornire un adeguato background culturale. Un imaging onnicomprensivo della malattia aterosclerotica coronarica dovrebbe essere in grado di visualizzare l’intero albero coronarico e caratterizzare la placca nei suoi vari aspetti quali la morfologia tridimensionale, il rapporto con il lume, la composizione tessutale, il rimodellamento vascolare e la presenza di infiammazione. Nessuna tecnica riesce singolarmente a fornire un quadro talmente completo e nessuna modalità disponibile identifica in modo inequivocabile la placca vulnerabile. Particolare attenzione è stata rivolta alla tomografia computerizzata multistrato, che sembra, al momento, la tecnica piú promettente nel panorama delle metodiche non invasive per la quantificazione complessiva per immagini della malattia aterosclerotica coronarica.

Diagnostic accuracy of 64-slice CT in the assessment of coronary stents

PurposeThe purpose of this study was to assess the diagnostic accuracy of 64-slice computed tomography (64-CT) coronary angiography in the detection of coronary in-stent restenosis.Materials and methodsNinety-five patients (72 men and 23 women, mean age 58±8 years) with previous percutaneous coronary intervention with stenting and suspected restenosis underwent 64-CT (Sensation 64, Siemens). The mean time between stent deployment and 64-CT was 6.1±4.2 months. The scan parameters were: slices 32×2, individual detector width 0.6 mm, rotation time 0.33 s, feed 3.84 mm/rotation, 120 kV, 900 mAs. After the intravenous administration of iodinated contrast material (Iomeprol 400 mgI/ml, Iomeron, Bracco) and a bolus chaser (40 ml of saline), the scan was completed in <12 s. All coronary segments with a stent were assessed on 64-CT by two observers in consensus and judged as: patent, with intimal hyperplasia (lumen reduction of <50%), with in-stent restenosis (≥50%), or with in-stent occlusion (100%). The consensus reading was compared with conventional coronary angiography.ResultsFour patients were excluded because of insufficient image quality. In the remaining 91, we assessed 102 stents (31 RCA; 10 LM; 54 LAD; 7 CX). In 14 (13.7%) stents, in-stent restenosis (n=8) or in-stent occlusion (n=6) was found. Intimal hyperplasia was detected in 11 (10.8%) stents. The sensitivity and negative predictive value of 64-CT for in-stent occlusion were 100% and 100%, respectively, whereas for all stenoses, >50% they were 92.9% and 98.7%, respectively.ConclusionsWe found that 64-CT has a high diagnostic accuracy for the detection of in-stent restenosis in a selected patient population.RiassuntoObiettivoValutare l’accuratezza diagnostica dell’angiografia coronarica con TC a 64 strati (64-TC) nella re-stenosi degli stent coronarici.Materiali e metodiIn 95 pazienti (72 maschi e 23 femmine, età media 58±8 anni) precedentemente sottoposti a posizionamento di stent intra-coronarico e con sospetta re-stenosi, è stata effettuata una 64-TC (Sensation 64, Siemens). Il tempo medio tra il posizionamento dello stent e l’esame 64-TC è stato 6,1±4,2 mesi. I parametri di scansione erano: strati 32×2 (sovracampionamento sull’asse z mediante flying focal spot), collimazione individuale 0,6 mm, tempo di rotazione 0,33 s, avanzamento 3,84 mm/rot, kV 120, mA 900. Dopo la somministrazione di mezzo di contrasto iodato (Iomeprolo 400 mgI/ml, Iomeron; 100 ml a 5 ml/s) e bolus chaser (40 ml di soluzione fisiologica a 5 ml/s), la scansione è stata completata in meno di 12 s. Tutti i segmenti coronarici con uno stent sono stati valutati da due osservatori in consenso e giudicati come segue: pervi, con iperplasia intimale intra-stent (IIS; riduzione del lume <50%), con re-stenosi intra-stent (RIS; ≥50%), o con occlusione intra-stent (OIS; 100%). La lettura in consenso è stata confrontata con i risultati della coronarografia convenzionale.Risultati4 pazienti sono stati esclusi dall’analisi per insufficiente Qualityà della scansione. Nei rimanenti 91 pazienti sono stati valutati 102 stent (31 in arteria coronaria destra; 10 del tronco comune sinistro; 54 della arteria discendente anteriore; 7 nell’arteria circonflessa). In 14 (13,7%) stent era presente una RIS (8) o una OIS (6). In 11 (10,8%) stent è stata, invece, rilevata una IIS. La Sensibilityà ed il valore predittivo negativo per la rilevazione di OIS sono state rispettivamente, 100% e 100%, mentre quelle per la rilevazione di RIS+OIS sono state, rispettivamente, 92,9% e 98,7%.ConclusioniLa 64-TC fornisce una accuratezza diagnostica elevata nella rilevazione della re-stenosi intrastent in una popolazione selezionata di pazienti.

Assessment of left main coronary artery atherosclerotic burden using 64-slice CT coronary angiography: correlation between dimensions and presence of plaques

PurposeThe aim of this study was to correlate left main (LM) coronary artery dimensions with the presence of atherosclerosis by multidetector-row computed tomography (MDCT) coronary angiography (CA) and to assess coronary atherosclerotic plaques with a semiquantitative method.Materials and methodsSixty-two consecutive patients (41 men, mean age 60±11) with suspected coronary artery disease underwent 64-MDCT coronary angiography. LM dimensions (length, ostial and bifurcation diameters), quantitative [location, Hounsfield unit (HU) attenuation] and qualitative (composition, shape) analysis of plaques within the LM were performed. All patients underwent conventional CA.ResultsThirty patients (mean age 55±10) without plaques in the LM presented the following average dimensions: length 10.6±6.1 mm, ostial diameter 5.5±0.7 mm, bifurcation diameter 4.9±0.9 mm. LM plaques (n=36) were detected in 32 patients (mean age 64±10) with the following LM average dimensions: length 11.3±4.0 mm, ostial diameter 6.0±1.2 mm and bifurcation diameter 6.0±1.2 mm. Plaques were calcified (40%, mean attenuation 742±191 HU), mixed (43%, mean attenuation 387±94 HU) or noncalcified (17%, mean attenuation 56±14 HU) and were frequently eccentric (77%). Age was significantly different in the two groups (p<0.05). LM diameters of patients with plaques were improved (p<0.05). A moderate correlation was found between the LM bifurcation diameter and the corresponding plaque area (r=0.56). Significant conventional CA lesions of the LM were present in just three patients (5%).ConclusionsIncreased LM diameters are associated with the presence of atherosclerosis. MDCT CA indicates relevant features of LM atherosclerotic burden, as rupture and subsequent thrombosis of vulnerable plaques may develop from lesions characterised as nonsignificant at conventional CA.RiassuntoObiettivoDescrivere l’andamento dell’aterosclerosi nel tronco comune sinistro (TCS) correlata alle dimensioni del vaso mediante angiografia coronarica con TC multistrato (AC-TCMS). Valutare le placche aterosclerotiche coronariche con un metodo semiquantitativo.Materiali e metodiÈ stato esaminato un gruppo di 62 pazienti consecutivi (41 uomini, età media 60±11) sottoposti ad AC-TCMS con scanner a 64 strati per sospetta malattia aterosclerotica coronarica. Sono state misurate le dimensioni del TCS (lunghezza, diametri all’ostio ed alla biforcazione), nonché è stata effettuata un’analisi quantitativa (sede, densità HU) e qualitativa (composizione, forma) delle placche in esso presenti. Tutti i pazienti sono stati sottoposti ad angiografia coronarica convenzionale (ACC).RisultatiTrenta pazienti (età media 55±10) senza placche nel TCS presentano le seguenti dimensioni medie: lunghezza 10,6±6,1 mm, diametro all’ostio 5,5±0,7 mm, diametro alla biforcazione 4,9±0,9 mm. In 32 pazienti (età media 64±10) sono state riscontrate placche aterosclerotiche (n=36) nel TCS, che presenta le seguenti dimensioni medie: lunghezza 11,3±4,0 mm, diametro all’ostio 6±1,2 mm, diametro alla biforcazione 6±1,2 mm. Le placche sono risultate calcifiche (40%, attenuazione media 742±191 HU), miste (43%, attenuazione media 387±94 HU), o non-calcifiche (17%, attenuazione media 56±14 HU), frequentemente con aspetto eccentrico (77%). L’età è risultata significativamente differente nei due gruppi (p<0,05). I diametri sono aumentati nei pazienti con placche (p<0,05). Una correlazione moderata è stata riscontrata tra il diametro del TCS alla biforcazione e la corrispondente area della placca (r=0,56). Lesioni significative del TCS alla ACC sono state riscontrate solamente in 3 pazienti (5%).ConclusioniL’aumento dei diametri del TCS si associa alla presenza di aterosclerosi. La AC-TCMS mette in evidenza aspetti fondamentali del carico aterosclerotico del TCS dal momento che la rottura e la conseguente trombosi delle placche vulnerabili possono svilupparsi a partire da lesioni non significative alla ACC.

Lesions of Proximal Coronary Arteries

Coronary artery disease (CAD) remains the leading cause of death in the Western world. Conventional coronary angiography (CCA) is the gold standard method for evaluation of the vascular lumen and provides excellent results in demonstrating stenotic lesions of CAD. However, it is an invasive procedure with a small risk of fatal events. Furthermore, CCA is a lumen-oriented technique that does not permit a direct visualization and evaluation of the coronary artery wall. The characterization of coronary plaques without a significant lumen narrowing is also not feasible with CCA. This information is relevant since the comparison of angiographic studies of coronary arteries performed before and after non-fatal myocardial infarction has shown that 49% of the pre-existing lesions before MI was <50% of stenosis (Fishbein and Siegel 1996). The detection of vulnerable atherosclerotic plaques within the wall of the coronary arteries could represent a key factor for the prevention of acute events (Naghavi et al. 2003).

Rottura di aneurisma dell’aorta addominale

1. n nFase arteriosa (Fig. 1b) e fase portale (Fig. 1c). n n n n n2. n nNella fase portale e possibile evidenziare un netto enhancement nel contesto della raccolta retroperitoneale, segno di sanguinamento attivo. n n n n n3. n nNella scansione pre-contrastografica (Fig. 1a) si evidenzia la discontinuita della parete calcifica dell’aneurisma (freccia) e la presenza di un’area di iperdensita (punta di freccia), espressione di un ematoma acuto formatosi nel contesto della parete del trombo. n n n n n4. n nLe immagini MPR, pur non presentando una rappresentazione panoramica dei rilievi dell’aorta e dello spandimento ematico circostante, sono quelle dotate di maggiore accuratezza per l’evidenziazione sia del sito di rottura che dello spandimento ematico circostante.