Influência do escore de cálcio na gravidade de lesões coronárias moderadas avaliadas pelo ultrassom intracoronário / Influence of calcium score on the severity of moderate coronary lesions evaluated by intravascular ultrasound

INTRODUÇÃO: A área luminal mínima (ALM), obtida pelo ultrassom intracoronário (USIC), é preditora de eventos em pacientes com lesões de moderada gravidade, identificadas à angiografia coronária. Por outro lado, a presença de cálcio é preditora de estabilidade das lesões. O objetivo deste estudo é avaliar qual a influência da quantidade total de cálcio coronário, obtido pela tomografia computadorizada cardíaca (TCC), na gravidade de lesões moderadas, avaliadas por meio de USIC. MÉTODOS: Realizamos USIC de 27 lesões moderadas, em uma série consecutiva de 22 pacientes com indicação para o procedimento, e que tinham TCC prévia. Foram obtidas medidas da ALM, carga de placa e porcentual de área de estenose. RESULTADOS: Os pacientes eram, em sua maioria, do sexo masculino (85%), com idade de 60 ± 9 anos e 41% eram diabéticos. Observamos correlação significativa entre ALM e escore de cálcio total (r = 0,67; P = 0,002), mas não houve correlação entre escore de cálcio total e carga de placa (r = 0,02; P = 0,93) ou porcentual de área de estenose (r = 0,3; P = 0,32). Os preditores independentes da ALM na análise multivariada foram idade (P = 0,02), índice de massa corporal (P = 0,01), diabetes (P = 0,02), dislipidemia (P = 0,02), proteína C-reativa ultrassensível (P = 0,02), glicemia (P = 0,02), HDL-colesterol (P = 0,02), triglicerídeos (P = 0,02), fração de ejeção do ventrículo esquerdo < 50% (P = 0,02) e escore de cálcio total (P = 0,03). CONCLUSÕES: O escore de cálcio total apresenta correlação positiva com a ALM em artérias coronárias, sugerindo que maior quantidade de cálcio na árvore coronária implica lesões ateroscleróticas moderadas com maiores áreas luminais ao USIC.

BACKGROUND: The minimal luminal area (MLA) measured by intravascular ultrasound (IVUS) is a predictor of cardiovascular events in patients with angiographically moderate lesions. On the other hand, the presence of calcium is a predictor of lesion stability. The objective of this study is to evaluate the influence of the total amount of coronary calcium, obtained by multislice CT scanner (MDCT), on the severity of moderate lesions as assessed by IVUS. METHODS: IVUS was performed in 27 moderate lesions in a consecutive series of 22 patients with indication for the procedure who had a previous MDCT. Measurements of the minimal luminal area (MLA), plaque burden and percentage area stenosis were obtained. RESULTS: Most patients were male (85%), with mean age of 60 ± 9 years and 41% were diabetic. A significant correlation was observed between the MLA and total calcium score (r = 0.67; P = 0.002), but there was no correlation between the total calcium score and plaque burden (r = 0.02; P = 0.93) or percentage area stenosis (r = 0.3; P = 0.32). Independent predictors of MLA in the multivariate analysis were age (P = 0.02), body mass index (P = 0.01), diabetes (P = 0.02), dyslipidemia (P = 0.02), high-sensitive Creactive protein (P = 0.02), glucose (P = 0.02), HDL-cholesterol (P = 0.02), triglycerides (P = 0.02), left ventricular ejection fraction < 50% (P = 0.02) and total calcium score (P = 0.03). CONCLUSIONS: The total calcium score correlates positively with MLA in coronary arteries, suggesting that a large calcium burden in the coronary tree is related to angiographically moderate lesions with larger luminal areas at IVUS.

Influência do perfil lipídico em placas ateroscleróticas coronarianas moderadas: análise com ultrassom intracoronariano / Relationship between lipid profile and coronary plaque burden: an intravascular ultrasound analysis

Introdução: O controle do perfil lipídico é uma das medidaschave para se reduzir a incidência de eventos cardíacos em coronariopatas. Objetivamos com este estudo determinar qual componente lipídico sérico tem maior influência no tamanho do ateroma por meio da análise de lesões coronarianas moderadas ao ultrassom intracoronariano. Método: Realizamos análise com ultrassom intracoronariano de 35 lesões moderadas em uma série consecutiva de 31 pacientes com indicação para o procedimento, realizando medidas das áreas da secção transversa (CSA) da membrana elástica externa (MEE), do lúmen, e da placa e média (P&M), e a carga de placa na área luminal mínima lesional (ALM)...

Objectives: Lipid profile control is a key measure in order to reduce the incidence of future cardiac events in the setting of coronary artery disease. We aim to determine which lipid profile parameter has greater influence on atheroma size using intravascular ultrasound analysis of moderate lesions. Methods: We performed intravascular ultrasound analysis in a consecutive series of 31 patients presenting 35 moderate lesions, measuring the cross-sectional area (CSA) of vessel, lumen, plaque & media (P&M) and plaque burden at the minimal lumen area...

The axial distribution of lesion-site atherosclerotic plaque components: an in vivo volumetric intravascular ultrasound radio-frequency analysis of lumen stenosis, necrotic core and vessel remodeling.

Radio-frequency intravascular ultrasound (IVUS) analysis characterizes atherosclerotic plaques into necrotic core (NC), dense calcium (DC), fibrofatty (FF) and fibrotic (FI) tissue. We studied axial plaque component distribution with respect to stenosis and remodeling. Preintervention virtual histology (VH) IVUS was performed in 81 pts (90 de novo lesions: 43 left anterior descending artery [LAD] and 47 right coronary artery [RCA]). VH-IVUS at the reference, minimum lumen area (MLA) and maximum NC (MaxNC) sites were analyzed. Pullback length of 31.1 +/- 12.0 mm spanned a lesion length of 13.8 +/- 9.5 mm. The MaxNC site was located at the MLA in 3.3% of lesions, proximal to the MLA in 61% of lesions (by 4.11 mm) and distal to the MLA in 35.6% of lesions (by 3.56 mm). The %DC was greater at the MaxNC and %FI and %FF plaque were less than at the MLA site. Lesion fiberoatheromas (FAs) were more often detected at the MaxNC than the MLA (96% versus 51%) and were more often classified as thin-caped or multilayered than the MLA sites. The remodeling index was larger at the MaxNC than MLA sites and correlated with the NC area both at the MLA (r(2) 0.068, p = 0.013) and at the MaxNC (r(2) 0.074, p = 0.009). In conclusion, grey-scale and VH-IVUS analysis showed that the MLA is rarely at the site of greatest instability (largest NC and remodeling) and necrotic core on VH is correlated with remodeling index. These in vivo findings are consistent with previously reported histopathologic data and have important implications for the detection and treatment of coronary artery disease.

In vivo virtual histology intravascular ultrasound correlates of risk factors for sudden coronary death in men: results from the prospective, multi-centre virtual histology intravascular ultrasound registry.

AIMS: We hypothesized a relationship between virtual histology intravascular ultrasound (VH-IVUS) findings and risk factors histopathologically associated with sudden coronary death (SCD) in men: cigarette smoking and an increased total cholesterol-to-high-density lipoprotein cholesterol (HDL-C) ratio (TC/HDL > 5). METHODS AND RESULTS: We assessed volumetric VH-IVUS parameters in a consecutive series of 473 male patients: fibrous, fibro-fatty, dense calcium (DC), necrotic core (NC), and a calculated NC/DC ratio. Patients' age was 61 ± 11 years, with 27% smokers and 69% having a lipid disorder. The NC/DC ratio was the only VH-IVUS parameter related to both TC/HDL ratio (r = 0.18, P= 0.0008) and low-density lipoprotein cholesterol levels (r = 0.17, P= 0.002); had a negative correlation with HDL-C levels (r = -0.11, P= 0.03); and was higher for smokers [median 1.98 (1.35-3.18)] vs. non-smokers [median 1.70 (1.23-2.53), P= 0.006]. An NC/DC value >3 was the threshold that best identified smokers and/or patients presenting TC/HDL >5 (odds ratio 3.0, 95% CI 1.7-4.9, P= 0.0001), and receiver-operator curves showed the superiority of the NC/DC ratio [area under curve (AUC) 0.64, P < 0.0001] over %DC (AUC 0.58, P= 0.006) or %NC (AUC 0.51, P= 0.43) to identify these patients. CONCLUSION: The ratio of NC to calcification detected by VH-IVUS in diseased coronary segments is related to known risk factors for SCD and, thus, may be associated with a worse prognosis.

Necrotic core and its ratio to dense calcium are predictors of high-risk non-ST-elevation acute coronary syndrome.

Increased creatine kinase-MB levels and ST-segment depression are well-known prognostic factors in the setting of non-ST-elevation acute coronary syndrome (ACS). We hypothesized a relationship between virtual histology intravascular ultrasound (VH-IVUS) findings and these prognostic factors. We performed "whole vessel" VH-IVUS analysis in culprit arteries of 225 patients with ACS and measured the 4 basic VH-IVUS coronary plaque components--fibrous, fibrofatty, dense calcium (DC), and necrotic core (NC)--and calculated a NC/DC ratio. Patients' age was 62 +/- 11 years; 72% were men and 23% had diabetes. Only the NC/DC ratio had a positive association with creatine kinase-MB levels (r = 0.21, p = 0.03), and it was significantly higher for patients with ST-depression compared with those with non-ST-depression ACS (1.97 +/- 1.46 vs 1.58 +/- 1.10, p = 0.02). Sensitivity and specificity curves determined that a NC/DC value > or =2 (odds ratio 3.8, p = 0.01) and percentage of NC > or =6 (odds ratio 3.1, p = 0.04) were thresholds that best separated patients with high-risk non-ST-elevation ACS from those without abnormal creatine kinase-MB or ST depression. Patients with both predictors had significantly higher total cholesterol (204.7 +/- 60.5 vs 173.6 +/- 44.3 mg/dl, p = 0.01), higher low-density liprotein cholesterol (132.5 +/- 49.8 vs 101.3 +/- 33.2 mg/dl, p = 0.02), and more myocardial injury (creatine kinase-MB value of 42 +/- 38 vs 12 +/- 21, p = 0.01) than patients with no predictors. In conclusion, VH-IVUS analysis showed that the percentage of NC and its ratio to DC in diseased coronary segments are positively associated with a high-risk ACS presentation.

Análise volumétrica tardia após implante de stents eluidores de sirolimus versus biolimus A9 / Late volumetric analysis after implantation of sirolimus versus biolimus A9-eluting stents

Os stents eluidores de sirolimus (SES) reduaem significativamente a incidência de reestenose e de eventos cardíacos maiores em comparação a stents convencionais. O sirolimus A9 (BA9), um análogo do sirolimus, demosntrou eficácia e segurança simulares no estudo randomizado e controlado STEALTH I. O objetivo deste estudo é comparar a eficácia do stent eluidor de BA9 com os SES, assim como seu desempenho em relação ao respectivos grupos controle, utilizando a análise volumétrica pelo ultra-som intracoronário (3D-USIC). Método: No total, 45 pacientes foram randomizados 2:1 para o grupo submetido a implante de stents eluidores de BA9(n igual 30) ou para o grupo conrole (n igual 15). Os resultados de angiografia coronária quantitativa e 3D-USIC foram comparados a uma série histórica de pacientes submetidos a implante de SES (n igual 30) ou controle (n igual 15). As características clínicas e angiográficas foram semelhantes entre os grupos , exceto pela maior quantidade de lesões tipo C e mulheres no grupo dos stents eluidores de BA9. Resultados: Aos seis meses de seguimento, a perda tardia intra-stent foi significativamente inferior...

Introduction: Sirolimus-eluting stents (SES) significantly reduce restenosis and major adverse cardiac events (MACE) compared to bare metal stents (BMS). The novel sirolimus analog, Biolimus A9T (BA9), presented similar safety and efficacy in the randomized, controlled STEALTH I trial. This study compared the efficacy of a BA9-eluting stent versus sirolimus-eluting and bare metal control stents. Methods: Forty-five patients with de novo coronary lesions were randomly assigned in a 2:1 basis to receive either BA9-eluting (n = 30) or bare metal (n=15) S-stents. Quantitative coronary angiography (QCA) and intravascular ultrasound (IVUS), at 6 months, were then compared to a matched series of patients who received either sirolimus-eluting (n = 30) or bare metal (n = 15) Bx Velocity stents. Baseline clinical and angiographic characteristics were similar among all groups, except for a significantly higher percentage of females and Class C lesions in the BA9-eluting stent group. Results: At 6 month follow-up, there was no significant difference in clinical outcomes between any of the groups. QCA revealed significantly lower late loss in both drug-eluting stents (DES) groups compared to bare metal controls, but no significant difference between BA9 and SES groups was observed (0.24 ± 0.39mm vs. 0.15 ± 0.38mm, p = NS). Obstruction volume measured by 3D IVUS was significantly reduced in both DES groups compared to bare metal controls, but did not differ between the BA9 and SES groups (2.23% vs. 3.30%, BA9 vs. SES, p=NS). Conclusions: BA9-eluting stents reduce neointimal hyperplasia, safely and effectively, compared to BMS, and the magnitude of this inhibition is similar to that of SES.

Treatment of restenotic drug-eluting stents: an intravascular ultrasound analysis.

BACKGROUND: The intravascular ultrasound (IVUS) findings during repeat intervention for drug-eluting stent (DES) restenosis have not been well described. METHODS: We identified 62 consecutive DES restenosis lesions (45 sirolimus-eluting stents and 17 paclitaxel-eluting stents) undergoing repeat intervention with pre and postintervention IVUS. Lumen, stent and intimal hyperplasia (stent minus lumen) areas were measured at the minimal lumen area (MLA) site and minimal stent area (MSA) site. RESULTS: Repeat stent implantation was performed in 55 lesions (88.7%). Overall, MLA increased from 2.3 +/- 0.7 mm(2) preintervention to 4.6 +/- 1.6 mm(2) postintervention. Preintervention MLA was seen at exactly the preintervention MSA site in 42%, while 73% of postintervention MLAs were located at the preintervention MSA site. There was a strong correlation between the preintervention MSA and the postintervention MLA (r = 0.79; p < 0.001). Preintervention MSA was the strongest independent predictor of a larger postintervention MLA (coefficient 0.72; p < 0.001). CONCLUSIONS: The preintervention MSA was a major predictor of larger lumen area after repeat intervention for DES restenosis. Several IVUS studies have shown that stent dimensions do not change over time. Therefore, the MSA of the original stent implantation procedure still has the greatest impact on subsequent interventions to treat DES restenosis.

Assessing intermediate left main coronary lesions using intravascular ultrasound.

BACKGROUND: Angiographic assessment of a left main coronary artery stenosis (LMCS) is often difficult and unreliable. We aimed to evaluate the severity of ambiguous LMCSs by intravascular ultrasound (IVUS) and to clarify how frequently significant stenosis occurs in the "real world". METHODS: We retrospectively found 115 consecutive patients in our clinical IVUS database with a de novo, angiographically ambiguous, intermediate LMCS who underwent IVUS evaluation. Quantitative coronary angiography (QCA) and IVUS analyses were performed. We define a significant LMCS as a diameter stenosis >50% by QCA and a minimal lumen area <6.0 mm2 by IVUS. RESULTS: Ostial, mid, and distal LMCSs were seen in 44 (38.3%), 6 (5.2%), and 65 (56.5%) lesions. Overall, IVUS minimal lumen area and plaque burden measured 6.8 +/- 2.6 mm2 and 63% +/- 14%. A significant LMCS was seen in 51 (44.3%) lesions by IVUS but in only 15 (13.0%) lesions by QCA. In particular, only 36.4% of ostial lesions had a significant IVUS stenosis, and minimal lumen diameter by QCA was less well correlated with IVUS in ostial lesions than in other lesion locations. CONCLUSIONS: This real-world IVUS analysis showed that less than half of intermediate LMCSs had significant stenoses by IVUS assessment, especially for lesions located at the left main ostium. Such patients deserve IVUS assessment or physiologic assessment before blindly proceeding to revascularization.

Inibição da proliferação neointimal após o implante de stents eluidores de biolimus A9: Análise volumétrica tardia com ultra-som intracoronário / Supressiion of intimal proliferation after implantation of biolimus A9-eluting stents: 6-month single-center intravascular ultrasound follow-up

Introdução: O estudo STEALTH I demonstrou a eficácia e segurança dos stents eluidores de Biolimus A (BA9) em reduzir a perda-tardia angiográfica e apresentar uma baixa incidência de eventos cardíacos maiores, entretanto os achados de ultra-som intracoronário (USIC) ainda não foram descritos. O objetivo deste estudo é descrever os achados de análise volumétrica por USIC nos pacientes recrutados em nossa instituição. Métodos e Resultados: Quarenta e cinco pacientes apresentando lesão coronária de novo, única, foram randomizados 2:1 para receber stents eluidores de BA9 (n igual 30) ou stents controle (n igual 15). A média de idade foi de 58 anos, com 16 por cento diabéticos e 62 por cento do sexo masculino. As características clínicas e angiográficas foram similares entre os grupos. Aos 6 meses de seguimento não houve diferença significativa entre os grupos quanto a desfechos clínicos. O índice de hiperplasia intimal intra-stent foi inferior no grupo dos stents eluidores de BA9 em comparação ao grupo controle 0,19 mais/menos 0,08 vs. 2.71 mais/menos 0.50, ) menor 0.0001), assim como o percentual de obstrução...

Background: Biolimus A9 (BA9) is a novel sirolimus analog with similar antiproliferative properties. BA9-eluting stents reduce angiographic late-loss compared to bare metal stents (BMS), with a low incidence of major adverse cardiac events (MACE), as reported in the randomized, controlled STEALTH I trial. We describe the intravascular ultrasound (IVUS) volumetric findings of patients enrolled at our institution. Methods and Results: Forty-five patients presenting a single, de novo coronary lesion (2.5-4.0 mm vessels; lesion length <24 mm) were randomly assigned in a 2:1 basis to receive either BA9-eluting (n=30) or bare metal stents (n=15). Mean age was 58 years, with 16% diabetics and 62% men. Baseline clinical and angiographic characteristics were similar between groups. At 6 month follow-up, there was no statistical difference in clinical outcomes between groups. In-stent intimal hyperplasia index measured by IVUS was 0.19+/-0.08 mm3/ mm3 for the BA9 group vs. 2.71+/-0.50 mm3/mm3 for BMS controls. The percentage of stent obstruction was also significantly lower for the BA9 group when compared to BMS (2.2+/-0.80% vs. 19.9+/-4.67%, P<0.0001). No stent thrombosis, aneurysm formation or incomplete stent apposition was observed in any group. Conclusions: Using IVUS volumetric analysis, we showed that BA9-eluting stents have a potent inhibitory effect on neointimal proliferation when compared to BMS at 6-month follow-up.